10TH ISSUE4TH YEAR OCTOBER,2014

Science Horizon

Editorial Board

Prof. Gopendra Kishore Roy

Prof. Govind Chandra Sahoo

Prof. Tarini Charan Panda

Prof. Arun Chandra Sahu

Prof. Niraj Kanti Tripathy

Prof. Satyaban Jena

Prof. Bijay Kumar Parida

Prof. Madhumita Das

CONTENTS

Subject Author Page1. Editorial : Elderly, the Repository of Prof. Tarani Charan Kara 2

Inherited Wisdom and Experience

2. Reversing Aging Dr. Debendranath Nayak 33. The Golden Hour of Motherhood Dr. P. Pallavee 8

Dr. Ramesh Chandra Parida

4. The Story of the Quantum Particle 'Boson' Prof. Rama Sankar Rath 11

5. Yakult : A Healthy Pro-biotic Drink Prof. Gopendra Kishore Roy 136. Application of Natural Dyes in Textiles Tusharbala Sahoo 15

7. Food Allergens Dr. Basanta Kumar Choudhury 18

8. Jack-of-All-Trades-Antony Van Leeuwenhoek Prof. (Dr.) K. Pravakar 21Prof. (Dr.) G. C. Sahoo

9. Say No to E-Cigarettes Too! Dr. Guru Prasad Mohanta 2610. Make your own Hydraulic Lift Model Sri Nikunja Bihari Sahu 28

11. Plastic Low Tunnel Technology forOff-Season Cultivation of Cucurbits Dr. Nityamanjari Mishra 29

12. The World of Akash Dr. Soumendra Ghosh 33

13. LED - Twentieth Century Electric Bulb Er. Mayadhar Swain 3614. Grid Cells, Place Cells and Navigation:

2014 Nobel in Physiology/Medicine Professor Niraj K Tripathy 40

15. 3D Printing Technology Mrs. Sushree Mishra 43

16. Health Security Against the Invisible Killer Er. Ramesh Chandra Sahoo 46

17. Quiz on Water Birat Raja Padhan 47

The Cover Page depicts : Protect Seniors Cover Design : Sanatan Rout

President, Odisha Bigyan AcademyProf. Uma Charan Mohanty

AdvisorProf. Sodananda Torasia

Chief EditorProf. Niranjan Barik

EditorProf. Tarani Charan Kara

Managing EditorDr Rekha DasSecretary, Odisha Bigyan Academy

EDITORIALELDERLY, THE REPOSITORY OF INHERITED WISDOM AND EXPERIENCE

Some persons are physically old at 40 whilesome are young at 60 by their abilities and activities.The reason being tha t the genetic set-up,socioeconomic, educational and living pattern of one'individual is distinct' from the other. However, ageingis an inevitable and universal process seen in all livingorganisms. Thephysicaldeterioration dueto advancingage makes a person 'aged' or old which can be broadlycategorized into two groups i.e. 'young old' (60-75 or80 yr), 'old-old' (>80 yrs). Lack of family care,deprivation of social status, honour, power, love,obedience from the family members, dependency,unwantedness etc. may increase the stress level andaccelerate ageing in the elderly.

Due to low mortality rate and improved healthcare, a rapid increase in the number of older people isseen worldwide, including India.Arecent report releasedby the United Nations Population Fund's (UNFPA),has indicated that the demographic dividend of Indiaby having a larger proportion of youthpopulation (356million 10-24 year olds) than rest of the world isexpected to last till 2025, after which the growth rateof the elderly is likely to take over. India is ageing fasterthan the global average and by 2050, the rest of theworldwill havea larger preparation of youthpopulationthan India, the United Nations' Population Projectionsshows.This demographic transition accompanied bythe socio-economic and cultural changes give rise tomany psychosocial problems for the elderly.

One of the socio-psychological problems of oldage is low self-esteem and depression. Retirement fromwork, loneliness, illtreatment in the family, physicalillness etc. are some of the common problems facedby the elderly people in the society.Widowhood isanother disruptiveevent in the life of an elderly person.

Unlike developed countries where resourcesare plenty, better employment opportunity and workculture with a higher retirement age of 67 years (forcertain professions in Australia, Greece, USA andScandinavian countries) and quality old age home, thescenario in our country with so much of heterogeneityand diversity is different andwouldface real challengesto meet the emerging needs of the elderly.

A change of attitude of the society and theGovernment towards ageing and the aged is essential.Let the young of today perceive ageing in its proper

perspective and understand the realities of life of theelderly in future. The best way to make life of theelderly worthwhile and useful is to understand theirexpectations and work towards that, so as to providea healthy psychological environment. Let them growwith strength, age with wisdom and die with grace.

Majority of the elderly people from rural areasare unaware of their constitutional rights as well asthe various Government policies and benefits availablefor them. Article 41 of the constitution has madeeffective provision for securing right of the old agepeople. The maintenance and welfare of parents andsenior citizens Act 2007 enacted in Dec. 2007, ensuresneed based maintenance for parents and senior citizensand their welfare. The Act makes maintenance ofparents/senior citizens by their children/relativesobligatory through tribunals, provides for revocationof transfer of property in case of negligence by thechildren and penal provision for abandonment of seniorcitizens. A collective effort of all the stake holders ofthe society can help the elderly people to lead a happy,healthy and useful life.

A senior cit izen endowed with wisdom,experience and expertise should not think that he/shehas become unproductive and unwanted. For manyprofessionals retirement is not mandatory. Theycontinue to work until they retire themselves.

Better fitness level and a friendly job marketwould encourage many senior citizens to go in for anextended career. Their experience and expertise canbe, profitablyutilizedona part time basis or consultant/advisorial capacity. It is a win-win situation for boththe job provider and the employee. This makes sense,especially in a country like India which rates loweston the global pension index (according to the 2014Melbourne Mercere Global pension index). Thereemployment of senior citizens could solve a numberof psychosocial problems of the elderly population.Therefore, it is theduty of the society to create facilitiesfor elderly people so that they would not feel unwantedand alienated. Happiness can only come when olderpeople feel wanted and loved and are allowed tocontribute to the society. On the eve of world elderlyday this could be a befitting tribute to them. If thiscannot be accomplished then the advance of medicalscience in prolonging life will be of no avail.

Prof. Tarani Charan Karae-mail : dr_tckara@rediffmail.com

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REVERSING AGINGDr. Debendranath Nayak

From the dawn of human civilization tomodern times the study of aging has created a

lot of interest due to man's urge to live longer,

desire for youth, quest for rejuvenation,

disaster for old age and fear of death.Aging is

oftenused interchangeablywith "senescence".The state of old age is characterized by the

terminal part of the life. The study of aging is

known as gerontology. Geriatrics deal with the

health aspects of diseases assocaited with old

age. Aging is characterized by a decline inphysiologial functions, with increasing

incidence of decreasing resistance to death.

Ageing process are universal, intrinsic,

progressive and deleterious changes with

time. There are different systems in the bodywith different organs and tissues. The different

organs and tissues of the body are known to

age at different rates in the same individual.

However, it is thought that the mechanism of

aging lies at the cellular level. There arevarious effects of ageing. Some of which are

discussed below.

Effects of Aging

The changes that typically occur with

age include : loss of hearing ability, reduction

of the thymus gland to 5-10% of its originalmass by age 50. Levels of antibodies increase

with aging. The insulin sensitivity of glucose

uptake decrease. There is reduced sensitivity

to growth factors and hormones due to fewer

receptors and disfunctional post-receptor pathways. Body weight declines after the age of

55 due to loss of lean tissue, water and bone(cell mass at the age of 70 is 36% of what it

is at age 25). Body fat increases up to 60years. Muscle strength declines 30-40% from

30 to 80 years. Reaction time declines 20%from 20 to 60 years. Elderly people tend to

sleep more lightly, more frequently and forshorter periods. Most people develop cataracts

during old age. About half of those over 85are disabled (defined as the inability to use

public transportation) over 75% of people of85years ofage have3-9pathologicalconditions,

and the cause of death for those people isfrequently unknown.Aging changes which are

not associated with a specific disease, butwhich are associated with a generalized

increase in mortality would qualify asbiomarkers of aging -and would distinguish

biological age from chronological age.

Biomarkers would be better predictors

of the increased likelihood of mortality(independent of specific disease) than

the passage of time (chronological age).Cross- liking of collagen, insulin resistance

and long expiration capacity have beenproposed as candidates but, as yet, no

biomarkers of aging have been validated anduniversally accepted.

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Many Scientistshave wondered whethera single cause (probably cellular or hormonal)lies behind all aging phenomena- or whetheraging is inherently multi faceted. Differencesin lifespan between species raise criticalquestions, in this regard. Why a rodent livesup to 3 years, a horse up to 35 years and ahuman beinglives anaverage upto85-90 years ?Aren't the cells of all these organisms muchthe same ? Why is it that at the age of 3 about30% of rodents have had cancer, whereas atthe age of 85, about 30% of human beingshave had cancer ? Some species (such asturtles, alligators andsome sharks) show hardlyany sign of aging. Cancer cells and stem cellsseem 'immortal' when compared to other cells.

Theories of Aging

There are several theories toexplain this phenomenon. The primary controlof aging is believed to be genetically

" I will have anything.My taste buds have been shot for years."

programmed. There are other factors mostlyenviornmental which are also known to modifythe ageing process. Attempts to classifytheories of aging have led to the two majorclassifications : programmed aging and wear& tear aging. Programmed aging would beaging due to something inside an organismscontrol mechanism that forces elderlinessand deterioration-similar to the way genesprogram other life-stages such as celldi fferentiations during embryologicaldevelopment or sexual maturation atadolescence. By contrast aging due to wear &tear is not the result of any specific controllingprogram, but is due to the sum total of effectsof many kinds of environmental assaults orstresses - i.e. damage due to radiation,chemical toxins, metal ions , free-radicals,hydrolysis, glycation , disulfide bond cross-linking etc. Such damage can affect genes,proteins, cell membranes, enzyme functions,blood vessels etc. and accelerates the agingprocess(es).

Need for Biomakers of Aging

Individuals of different species seem to

age at different rate for different reasons.Laboratory studies of lifespan is currentlyonly feasible for short-lived species, but ifsome biomarker could be found fordetermining biological age (rather thanchronological age) then human lifespan studies

would be feasible. Unfortunately, we evenlack a method of biomarker validation.And ifa biomarker could be validated for rodents,

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OCTOBER,2014

how could we prove that the same biomarkerwould be applied equally-well to humans ?Without biomarkers of aging we cannot saydefinitively if "accleratedaging" diseases exist.

Without validated biomarkers of aging,it is difficult to prove that nutrients, drugs orother interventions are slowing aging andextendingthe maximum lifespan of humans.With biomarkers, it would only be necessaryto show reduced deterioration within areasonable time-frame(a few years). Inhuman-without biomarkers, positive proof of an antiaging intervenation for humans could onlycome by observing effects on lifespan instudies lasting decades or centuries. To be ofuse within our own lifetimes, the result fromshort-lived mammals may be the best we canhope for if biomarkers are not found.

In sofar as caloric restriction with

adequate nutrition (CRAN) seems to slowaging in rodents and many other short-livedspecies, long-term studies of CRAN onmonkeys are being conducted to establish ifCRAN also slows aging in primates.Althoughit will take decades for these studies to run to

completion and current data is not yetstatistically significant, rheasus monkeys onCRAN show the same reduction of bodytemperature and plasma insulin as CRANrodents , as well as showing a slower declinein serum Dehydro Epi Aandrosterone Sulfate

(DHEAS). Men with greater survival in theBaltimore longitudinal study of aging alsoshow reduced body temperature and plasma

insulin, along with elevated serum DHEAS-suggesting that these three factors may bebiomarkers of biological age [science297:811(2002)].

Relevance of Caloric Restriction withAdequate Nutrition

Caloric restriction with adequate

nutrition (CRAN) dramatically extends themaximum life Span of laboratory animals.Victims of starvation and malnutrition arenot experiencing the life extending benefits ofCRAN -adequate nutrition (vitamins, minerals,essential amino acids and essential fatty acids

in adequate quantities) is absolutely necessaryfor caloric restricted diets to extend life span.Because almost every aspect of the agingprocess appears tobeslowedbyCRAN,studyingCRAN has become a means of defining andunderstanding the agingprocess itself including

the search for biomarkers of aging.

Themechanismby whichcaloric restrictionhas such dramatic effects is unproven, butmaturity, thymus shrinkage,DNA-repairdeclineand tumorformationis delayed.The experimentalanimals show more complete oxidation offatty aids, with fewer ketones (R'RC=0)in theblood, and cell membranes have lesscholesterol and saturate fatty acids. Collagencross-linking occurs more slowly in rats onCRAN which have a reduced blood glucoselevels of about 15%below controls. Reductionof visceral bodyfat is associated with reducedinsulin resistance whichmay be due to reducedlevel of the proinflammatory cytokine.

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Although CRAN animals produce lessfree radicals; their metabolic rate (oxygenconsumption pergram of tissue) is not reduced.The inner mitochondrial membrane of CRANanimals have a higher saturated\unsaturatedfat ratio making themlessvulnerable to protonleak from lipid peroxidation. Both stage 3 andstage 4 respiration rates are greatly reduced inbrain, heart and kidney tissue. CRAN rats show15% less plasma glucose and 50% lessplasma insulin than controls, having same rateof glucose utilization per unit mass, meaningthat glucose is being more effectively utilized.

A prime candidate for a biomarker ofaging has been insulin resistance. Reducedglycation may be achieved by reduction oftypical blood glucose levels. Low fat mealsare one means to achieve this because fattyacids promote insulin resistance -and greaterinsulin resistance means that higher bloodglucose are required to supply cells with same

"My bones are getting softer, but my arteries aregetting harder, so it balance out !"

amount of glucose (causing more glycation)(insulin resistance is a fundamental cause ofadult-on set diabetes.) also, increasedconsumption of soluble fiber (particularly thebeta-glucan found in oat bran and barley) lowers24-hour plasma glucose and insul inconcentrations. Experiments demonstratingthat lysine-glycation predicts early death inboth CRAN and freely-fed rats makes lysine-glycationa very promisingbiomarkers candidate.

Although no substance has been shownconclusively to extend maximum lifespan inhumans,a fewstudies indicatesome supplementsmay extend the lives of laboratory mammals,(mice, rats or guinea pigs). Usually it is difficultto gain immediate benefit from insights intomolecular mechanism of aging, but enormousimmediate benefit can be gained by reducingcalorie intake (while maintaining adequatenutrition), avoiding tobacco, avoiding alcohol,exercising, taking supplements, eating low fat\ high fiber diets etc. Eidemiological evidenceindicates that adherence to a vegetarian dietfor more than two decades can increase lifespanby 3.6 years and cryonics may serve as 'first-aid' to transport as to the time when significantadvances in the elimination of senescencehave occurred.

Somegeronotologists believe that somaticgene therapy can accomplish such goals asremoving the telomerase gene from somaticcells (to reducecancer),migrating mitochondrialDNAintonucleusand utilizingbird mitochondriagenes to create modified human mitochondriawhich produce fewer free radicals.

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Reversing Aging

Biogerontologist, Aubrey de Greybelieves that reversing aging may actually bemore feasible than slowing aging, in the samesense that it is sometimes more economicalto periodically repair damage than to go toextraordinary expense to slow the rate ofdamage. Dr. De grey believes that the key torejuvenation is the repair of seven distinctkinds of damage that represent aging : cellloss, cell senescence, extracellular proteincross linking, nuclear DNA mutation,mitochondria l DNA mutation and theaccumulation of garbage inside cells as wellas outside cells. He has characterized therepair of the seven kinds of damage asStra tegies for Engineered NegligibleSenescence (SENS).

The seven repair strategies that Dr. De

Grey advocates can be summarized : (1) Cellloss can be repaired (reversed) just by suitableexercise in the case of muscle; but for othertissues it needs various growth factors tostimulate cell division. Or in some cases itneeds stem cells. (2) Senescent cell can be

removed by activating the immune systemagainst them. Or they can be destroyed by genetherapy to introduce "suicide genes" that onlykill senescent cell. (3) Protein cross - linkingcan largely be reversed by drugs that break thelinks. But for some of the links we may need

todevelop enzymatic methods. (4) Extracellulargarbage can be eliminated by vaccination thatgets immune cells to 'eat' garbage. (5) For

intracellular junk we need to introduce newenzymes, possibly enzymes from soil bacteriathat can degrade the junk that our own naturalenzymescannotdegrade. (6) For mitochondrialmutations the plan is not to repair them but toprevent harm from the mutations by puttingsuitably modified copies of mitochondrialgenes into nucleus by gene therapy. Themitochondrial DNA experiences so muchmutation damage because most of the freeradicals are generated in the mitochondria. Ifmitochondrial DNAcanbe moved into nucleusit will be better protected from free radicals,and there will be better DNA repair whendamage occurs. All mitochondrial proteinswould then be imported into the mitochondria.(7) for Cancer (the most lethal consequenceof mutations) thestrategy is to usegene therapyto delete the genes for telomerase and toeliminate telomerase-independent mechanismsof turning normal cells into "immortal" cancercells. To compensate for the loss of telomerasein stem cells we would introduce new stemcells every decade or so.

Reference : Aging of the genome. Jan Vijg (2007)

Modulation of aging and longevity . Surish Rattan(Editor) 2003

Aging at molecular level. Thomas Von Zglinicki(Editor) 2003

Immortality. Ben Bova (1998)

Why we age. Steven N. Austad (1997)

Ageless Quest. Leonard Guarante. (2003)

Ex-Principal, Dhenkanal Autonomous College158/2223, Nigamananda Nagar, Lane-2, Bhubaneswar-751010

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OCTOBER,2014

THE GOLDEN HOUR OF MOTHERHOOD* Dr. P. Pallavee

**Dr. Ramesh Chandra Parida

Motherhood is a heavenly experience. Itoverwhelms the motherwith theunique feelingof a creator that equates her with none other

than someone we perceive as God. Therefore,every moment of it is golden, but scientists

brand the first hour of it to be so, becauseduringit shefirst breast feeds hernewborn withthe real "nectar on the earth" - the colostrums,

which buildsup theimmunesystemand ensuresthe child a long and healthy life.

During pregnancy, the breasts enlarge in

response to high circulating levels of thehormones estrogen, progesterone,prolactin andpossibly human chorionicgonadotropin (HCG).

Therefore a small quantity of milk may besecreted evenfromthe fifth month of pregnancy.

In most animals, the actual milk secretion tomeet the requirements of the baby occurs

within an hour of delivery, while in humans, ittakes 1-3 days. After delivery, the baby startssuckling, whichevokes reflex oxytocin release

andmilkejection. However, during the first fewdays after deliverythe breasts of the new mother

mostly secrete colostrum.

Colostrum is a deep lemon yellow to

orange coloured thick and sticky fluidaccumulated in the mammary glands in the

latter part of pregnancy, which precedes theflow of milk at the onset of lactation andcontinues through the early days of breast

feeding. Because of its colour, for long, it has

been grossly mistaken as unfit for consumptionby the newborn until the milk is formed as adilute white liquid. Such belief has a twindisadvantage - the baby is deprived of a uniquefoodthat has all the natural ingredients to ensure

his/her good health, andin absence of suckling,the process of milk formation becomes lessefficient. We must bear in mind that nature isthe perfect creator. Whatever it creates, is thebest for whom it is created. Therefore,

colostrums is the best food for the newborn. Itis not only rich in minerals and aminoacids, butalso has more proteins, much of which areglobulin. It contains less sugar and fat, makingit easily digestible. Besides, it has a number of

antibodies, particularly, immunoglobulin A(IgA), which offers the newborn protectionagainst enteric pathogens.Ahost of other healthfactors found in colost rums includecomplement pro teins , macropahges,

lymphocytes, lactoferrin, lactoperoxidase andlysozymes. Colostrum also acts as a laxative,helping babies to pass early stools, which aidsin the excretion of bilirubin, thereby preventingneonatal jaundice. All these, along with many

such properties of colostrum make it a perfectfirst food for the newborn. The secretion of thisunique fluid persists for approximately fivedays, with gradual conversion to mature milkduring the ensuing four weeks.

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At the beginning, only a few spoonfulsof colostrums is produced, which appears tobe meager. However, nature has taken thisrecourse considering the fact that the volumeof the stomach of a newborn is quite small - itis only 5-7 ml for a one day old. On the otherhand, colostrum is a highly concentrated liquidhaving all the nutritious and health ensuringcomponents in the right quantities, to meet theexact requirements of the baby. Theconcentrations of all the immune factors aremuch higher in colostrum than in mature milk.

As for example, it is many times richer inleucocytes, the protective white blood cells,that destroy the disease causing bacteria andviruses entering the baby's body, and in IgA,which protects him from a number of germsthat attack themucous membrane, throat, lungsand intestines. Therefore, colostrum in factacts as a natural and 100% safe vaccine.Besides, colostrum also seals the pores of thehighly permeable intestines of the newborn,thereby preventing the foreign substances frompenetrating inside.

Table 1 : An approximate composition of colostrum and milk (per decliliter)

Component Human colostrum Human milk Cow's milkWater (g) 88 88Lactose (g) 5.3 6.8 5Protein (g) 2.7 1.2 3.3Casein / lactalbumin ratio 1:2 3:1Fat (g) 2.9 3.8 3.7Linoleic acid 8.3% of fat 1.6% of fatSodium (mg) 92 15 58Potassium (mg) 55 55 138Chloride (mg) 117 43 103Calcium (mg) 31 33 125Magnesium (mg) 4 4 12Phosphorus (mg) 14 15 100Iron (mg) 0.09 0.15 0.10VitaminA(mcg) 89 53 34Vitamin D (mcg) 0.03 0.06Thiamine (mcg) 15 16 42Riboflavine (mcg) 30 43 157Nicotinic acid (mcg) 75 172 85Ascorbic acid (mg) 4.4 4.3 1.6

(Ref. Review of Medical Physiology, William F. Ganong, 18th Edition, 1997)

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As the early breast feeding continues,gradually colostrums changes into mature

milk in the first few weeks after birth, but the

process begins from the third or the fourth

day. During the transition, the volume of milkproduced goes on increasing, and it appears

thinner and whiter. Therefore, the

concentrations of the antibodies decrease init. However, as the stomach capacity of the

baby also increases keeping pace with it, the

whole volume of milk produced at variousstages can be consumed by him/her if he/she

is breast-fed 8 to 12 times a day. As a result,

the total amount of different antibodies he/

she ingests, remains unchanged, which isenough to give the baby necessary protection

against infections. Therefore, the practice of

breast feeding must continue for at least 6months and preferably for 2 years. We must

keep in mind that in spite of best efforts, so

far, no suitable alternative to mother's milkhas been found.

A nursing mother easily produces about600 ml of milk daily. Its main constituents are

lactose, the easily digestible sugar, and very

unique types of proteins, which include

-lactalbumin, -lactalbumin and casein. It

also contains many essential and non-essential

aminoacids, fatty acidsand almost all vitamins,

except vitamin K (less of D). The serum ofhuman milk is rich in interleukin - 6, associated

closely with IgA production. Similarly,

epidermal growth factor (EGF) present in it

promotes growth and maturation of the new

born's intestinal mucosa.

Breast feeding is not only beneficial

for the baby, which keeps him/her healthy andimproves the IQ, but also good for the

mother's health as it stimulates oxytocinhormone that causes the uterus to contract

and to return to its normal size. It also helpsto burn the extra calories and lower the fat

stores, thereby preventing obesity in mother.It also aids in reducing the risks of breast

cancer, ovarian cancer, and osteoporosis, actsas a natural contraceptive and probably delays

menopause. Besides, it has been found toincrease the emotional bonding between the

child and the mother which continues lifelong.Therefore, no mother should refrain from

performing her first and foremost duty, tobreast feed her baby, right from the first hour

of delivery and continue as long as possible.That can make every hour of motherhood,

really golden.

*Qr. No. D(II) 18, JIPMER Campus, Dhanvantari Nagar,Puducherry - 605006

Mobile: 9489693270, Email: ppallavee@rediffmail.com**Plot No. 124/2445, Khandagiri Vihar, Bhubaneswar - 751030

"If a religion is defined to be a system

of ideas that contains unprovable statements;

then Godel has taught us that not only is

Mathematics a religion; it is the only religion

that can prove itself to be one."

- John D. Barrow

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OCTOBER,2014

THE STORY OF THE QUANTUM PARTICLE 'BOSONProf. RamaSankar Rath

Sommerfield's application of Fermi-Dirac's statistics in the investigation of motionof electrons in metals emerged quantum-statis tics as a new area of research.Satyendranath Bose was then a Professor inCalcutta University doing his research inclassical Physics. He was born in 1894 in aBengali family in Calcutta and joined theUniversity as a teacher in 1917 aftercompleting his Master's and then his Ph.D.Degree from the same University. Four yearsafterwards he joined Dacca University as aProfessor and continued till he returned toCalcutta University in 1945 where he stayedtill his retirement in 1956.

All through his long teaching career, hedevoted much of his time to research with adeep longing for discovering something new.He translated Einstein's papers on relativityfrom German to English and also the lecturesof Planck on Statistical mechanics. He spenttime in studying the book on Physics ofGibbs and the research papers of Einstein,Planck, Bohr and Sommerfeld. His aim wasto acquaint himself well with the latest workon quantum mechanics.

Afte r a lot of experiments anddeliberation planck had proposed a simpleformula P=n.u in black body radiation,expressing the density distribution P ofradiated energy as the product of a number nand nother term u which he established as

2

3n = n ( ) =

8c

andu = u ( T) =

hhexp( )-1kT

, .

Where c the velocity of light, itsfrequency and T is the temperature at whichradiation occurs in equilibrium. He took k andh as two constants, but assumed n as a functionof v along, while takingu of both v andT. Muchearlier Rabeigh had taken c to be the velocityof sound which beinga compression wave hasonly a single mode of vibration. Planck'sproposition that c is the velocity of light ( urelectromagnetic) wave meant that being atransversal wave it has two modes of vibration.Further Rabigh had taken the numberN insteadof n with N= .n, V being the volume of thehole where radiation takes place. It wasfortunate that the representation of u(v,T0 inthe form above worked in both the cases oflow as well as high frequency.

On the basis of their concise explanationconsistent with all the features of the photo-electric effect Einstein and Debye meanwhilehas proposed intuitively that radiation consistsof nothing but light energy of quanta hv.Madxwell's electro-magnetism theory had notbeen able to explain these features. Of the twon () and u (, T). The latter was the moreimportant term. Itprovided Einsteina techniquefor counting the indivisible energy quant hv.Bose had nothing to comment on thistechnique. All his interest was centred on thefactor n (). In the self-introductory letter toEinstein on 4th June 1924, his first ever, hewrote 'I have found an alternative proof for the

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co ef ficie nt 2 38 c/ in my own wayindependent of classical electrodynamics, onthe assumption that the elementary phase-space has content 3h . ' As Bose's postulationwas in consistence with his stipulated premisesthat both n( ) and n( T, ) were to be ofquantum origin. Einstein was impressed andinvited him to be his research colleague. Hearranged for Bose's manuscripts to betranslated in German and published.

Thus Bose-Einstein statistics, as it cameto be known later, worked within a logicalframe. For its application Einstein, on thebasis of his strong intuitive power, imaginedradiation to consist of material particles,instead of the photons as he imagined earlier.In that case when the ideally quantum gaswould be taken to extremely low enoughtemperature it would condense in a superfluidphase - a phenomenon unknown to classicalphysics. However the idea was still one ofimagination and did not quite satisfy him.Neither could Bose respond to the objectionsraised by him either through letters or inperson when he met him in Germany.

It must be stated here that the authenticsimplicity of Bose's derivation of the planckblack-body radiation law aroused so mucheagerness in Einstein to meet this young manfrom India thathe arranged for Bosea generoustwo-year travel fellowship. The burst of

creativity in Bose which was beginning towane was kept alive for a few more years whenEinstein showed interest in his fundamental

research and extended his helping hand. Thefellowship brought him the opportunity tocome in contact with Einstein and the Berlinestablishment as also with the scientistsLangevin and Marie Curie in Paris. Ofcourseafter these twoyears he returned to his teachingand research first in Dacca and then again inCalcutta.

When the question of application ofBose-Einstein Statistics was still open andwaited for a suitable quantum gas that wouldmeet Einstein's objections, Dirac came with aso lu tion. Through hi s pr inc iple ofsymmetrization he proposed a new particle,intermediate between photon and a materialparticle which would obey Bose Einsteinstatistics. He chose the name 'Boson' for thisnew particle of his imagination. Earlier, liquidHelium was the only available laboratorymani festa tion of the Bose-E inste incondensation. But even in its superfluid state,intermolecular interaction was still active,while the original model of an ideal quantumgas should be free from such a state of things.Thus Helium did not satisfy the theoreticalrequirements of Bose-Einstein statistics.

However after the 1980's and 1990'swith the condensation in dilute atomic gases attemperatures in the milli-and micro-kelvinranges, the situation changed drastically andBose's name came to the forefront of

contemporary physics along with Einstein's.

Aatreya Bhoomi, Plot - 107(p), Acharya Vihar,Bhubaneswar - 751 013 Phone: 0674-2542708

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OCTOBER,2014

YAKULT: A HEALTHY PRO-BIOTIC DRINKProf. Gopendra Kishore Roy

What are Pro-biotics ?

As per a 2001 definition by WorldHealth Organization pro-biotics are "Livemicroorganisms or beneficial bacteria, whichwhen administered in adequate amounts, confera health benefit on the host." Each one of ushasmore than 1000types ofbacteria numberingmore than 1000 trillion residing in ourdigestive tract. While some of them arebeneficial in helping us to break down ourfood and absorb nutrients, others are harmful.It is important that the beneficial bacteriaou tnumber the harmful ones for themaintenance of good health. For the treatmentof many of our diseases, we usually takeantibiotics which are designed to kill thedisease causing bacteria. However, the samecan also kill a number of intestinal flora thathelps the body in many ways. In addition,stress, infection, irregular diet , sleep, ageingetc. can disturb the balance between thebeneficial and the harmful microorganismpopulation in the body resulting decrease ofthe beneficial ones. This depletion of thebeneficial bacteria in the intestine leads toindigestion, infection and discomfort, whichcan be relieved with the use of pro-biotics.

Functions of Pro-biotic

Generally probiotics help to maintaina healthy digestive system by maintainingthe balance of the gut flora. Studies have

suggested that probiotics may play animportant role in improving bowel functionand hence prevent diarrhoea and constipation,gastro-intestinal disease like Irritable BowelSyndrome (IBS), cancers, allergic disorders

and respiratory diseases. Other healthbenefits of pro-biotic include:

Makes a nice supplement to antibioticsfor people suffering from urinary tractinfections.

Maintains a healthy immune system.

Helps in overall digestive management

A few probiotic foods, recommendedfor health benefits include:

(i) Yoghurt.

(ii) Kefir (a fermented dairy product whichis a combination of goat's milk and kefirgrains).

(iii) Sauerkraut (made from fermentedcabbage).

(iv) Dark chocolate.

(v) Microalgae (super food made fromsome ocean-based algae like : spirulina,chorella, blue-green algae).

(vi) Green pickles

Yakult

Yakult is derived from the word 'Jahurto'meaning 'Yoghurt' in Espernato. ( Espernato is

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an artificial language designed in 1887 foruniversal use). Also known as 'Yang Le Duo',yakult is a Japanese probiotic milk-like productmade by fermenting a mixture of skimmedmilk with special strain of bacterium'Lactobacillus casei' Shirota. It was developedby a Japanese scientist, Minoru Shirota in1935.After its use in Japan and Taiwan, it wasintroduced to Brazil in 1966 through theJapanese immigrants. Presently Yakult is soldin more than 30 countries while its bacteriaculture is provided from a mother strain fromJapan only, irrespective of the place ofproduction. It is marketedin different volumeshavingbottlesizesof65ml(inAustralia,NewZealand,Europe, India, Indonesia,Vietnam), 80ml ( in USA,Mexico, Japan, Philippines, South Korea,Thailand) and 100 ml (in Singapore, HongKong, Taiwan and the main land of China).

Nutritional Value

As a probiotic health drink, yakult isconsumed everyday as a part of the daily diet

by around 30 million people, the world over. A65 ml bottle of yakult contains more than 6.5billion beneficial bacteria (Lactobacillus caseiof the shirota strain) which are resistant tothe gastric juices and bile and reach theintestine alive to impart proven health benefits.

Yakult contains sugar (sucrose, dextrose),skimmed milk powder, natural flavours, liveLacyobacillus casei shirota strain of bacteria

and water. The nutritional value per 65ml ofYakult is as follows: Carbohydrates-12gm,Fat- less than 0.1gm, Protein-0.8gm andEnergy-50Kcal.

Yakult is recommended as a health drink,for all age groups, including children (oneyear and above) and pregnant women. It canbe consumed everyday as a part of our dailydiet. A few health benefits of drinking yakultdaily are :

Maintenance of gut flora

Modulation of the immune system

Regulation ofbowelhabitsandconstipation

Guard against some gastrointestinalinfections

Good drink for diabetics since sugarcontent is relatively less compared toother soft drinks like cococola andorange juice etc.

Gut plays a vital role in maintaining ouroverall health. Thus it should be kept healthyby drinking a bottle of yakult every day. InIndia, yakult is manufactured at a certifiedstate-of-the-art facility in Rai, Sonepat inHaryana and available in many big cities allover the country. (A pack of five bottles eachcontaining 65ml costs Rs.55.00-September,2014 price in Mumbai super market). In viewof its proven health benefits, Yakult can bepreferred as a daily drink compared to othercarbonated ones available in the market.

Retired Director and Professor of Chemical Engineering,

National Institute of Technology-Rourkela.Phone / Mob. - 0674-2560950/9437041390

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APPLICATION OF NATURAL DYES IN TEXTILESTusharbala Sahoo

Natural dyes are the colouring materials

derivedfromanimal or plant resources without

any chemical treatment. Some naturally

occurring minerals are also used to prepare

natural colours. The use of natural dyes have

been reported since pre-historic times when

the natural colourants were usually obtained

from berries, blossoms, barks and roots of

different plants. They were applied to the

textile fibres without any pretreatment of the

dye-material or the textile. In the middle of

thenineteenthcentury, introduction of synthetic

dyes marked decline in the use of natural dyes.

However with the scientific advancements in

the field, it has been realized that in addition to

the colour, some of the natural dyes also

induce antimicrobial properties to the textiles.

Therefore, the use of natural dyes in textiles

hasgained importanceagain with the increasing

trend of using natural substances

Sources of natural dyes

Natural dyes are mainly obtained fromthree sources such as : plants, animals and

minerals. There are more than 500 dyes ofplant origin, in which the colouring mattersare derived from the roots, leaves, bark, trunkor fruits. The common sources of natural dyesof plant origin are given in table 1.

The colourants of mineral origin arederived from specific natural mineral sources.

Purified inorganic compounds are used toprepare the so-called mineral colours. Someof the important mineral colourants arechrome-yellow, iron-buff, narkin-yellow,prussian-blue and manganese brown. The lac

insectdye is a common animal dyeof industrialimportance. The major sources of dyes fromanimals and minerals are given in table 2.However, the plantmaterialsare more commonlyused as dye materials all over the world.

Table 1 : Dyestuffs obtained from different plant parts

Part of the plants Sources of the Dyestuffs

Root Turmeric, Madder (Manjistha), Onion, Beet-root

Bark/ Branches Purple bark, Sappan wood, Shillicorai, Khair, Red Sandalwood,neem, jackfruit, sal, mahua, etc.

Leaf Indigo, Henna, Eucalyptus, Tea, Cardamom, Coral Jasmine, LemonGrass

Flowers (Petals) Marigold, Dahlia, Tesu, Kusum

Fruits/Seeds Latkan, Pomegranate rind, Beetle nut, Myrobolan (Harda)

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Table 2 : Dyestuffs obtained from different Animal parts and Minerals

Source Dyestuffs

Animals Cochineal insect (red), Cow urine (Indian yellow), Lac insect (red, violet),Murex snail (purple), Octopus/ Cuttlefish (sepia brown)

Minerals Ochre (oxide containing clays) for yellow, brown or red colour; limestoneor lime for white; manganese for black; cinnabar (mercury ore) for red; andmalachite for green; iron oxide (rust) for yellow-orange-brown colour

Preparation and application of naturaldyes from plants

The preparation of dyes from plantmaterials involves an extraction process. Thecollected source materials are generallyshadow dried in air or sun dried within a

temperature range of 37-40°C to reduce themoisture content to less than 10-15% level.After drying, the materials are ground to breakdown into very small units or preferablypowdered form. Thereafter the dyes can be

extracted from the above material by usingaqueous method i.e. using water as the solventfor extraction with or without addition of salt/acid/alkali/alcohol in the extraction bath. Othermethods as supercritical fluid extraction,

enzyme assisted extraction, alcoholic/ organicsolvent extraction are also used.

The stronger the dye extract, i.e., morethe plant sources used, the deeper the colour.Attractive colours can be obtained by mixingdifferent dyestuffs in the same dye bath. Aftercompletion of one dye, other can be mixed.

Different dyestuffs can be boiled separatelyand mixed in various proportions or they canbe boiled together. The quality of the extract

varies with the age, season, and other ecologicalconditions of the source.

The natural dyes can be kept in a coupleof different forms such as dried, powdered,fermented or extracted. However, the mostcommon form is simply, the dried plant

material kept in a crushed or powdered form.

In textiles, majority of natural dyes need

a chemical agent to fix the colour on thefabrics especially of plant origin (cotton)during dyeing or fabric printing. This chemicalagent is commonly known as mordant. Thefabric is impregnated with the mordant. Then

during the dyeing process, the dye reacts withthe mordant forming a chemical bond to attachit firmly to the fabric. The mordant helps toproduce faster shades by forming an insolublecompound of mordant and dyestuff within the

fibre itself. The mordant does not serve as acolour source on its own.

The choice of mordant depends upon thefabric. The four most commonlyused mordantsare alum (potassium sulphate), chrome(potassium dichromate), iron (ferrous sulphate)

and tin (stannous chloride). Besides thesemetallic mordants, a number of tannin

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containing substances like tannic acid and oilmordants are also in use.

Different mordants give different colourswith the same dye solution. As per example,for log wooddye, alumgives violet and purplishgrey, chrome gives turquoise blue, iron givesdark grey to black and tin gives purple colour.

Themordanting is called pre-mordanting,when it is applied first, followed by dyeing;post mordanting, when the dyeing is done firstand then mordanting is carried out, andsimultaneous mordanting, when mordant anddye are mixed together and applied.

The natural dyedyarnsare dulland muddy.With the right treatment and careful selectionof the mordants and dyestuffs, the colours canbe made bright. However, as there are lot ofvariations in the plantmaterials with respect totheir source, age, environment etc., thestandardization of the shade is often a problem.

Advantages of natural dyes

Clothes dyed with natural colours couldbe sold at higher prices. In addition, theapplication of natural dyes in the textileindustries have the following advantages.

The extraction of colours is easy byboiling the plants, or their parts (berries,leaves, bark or flowers) in water.

Natural dyes are more eco-friendly thanthe synthetic dyes since the syntheticdying procedure can produce pollutants.

The natural dyes are biodegradable andfree from carcinogenic components.

Most natural dyes are known asantioxidants. Some of the natural dye

materials have been found to impart

antimicrobial properties to the textiles.

Depending on the nature of the mordant

and source of the dye used, one dye can

give rise to a variety of colours (5 to 15

varying colours and shades).

The natural dye materials are aesthetically

appealing.

Thepreparation of natural dyes can resultin employment generation both in the

dyeing sector and in plantation.

Limitations

Despite the various advantages, the useof natural dyes is practised only in certain

clusters, that includes the art forms like

Kalmkari and in commercial practices like

Ikat weaving, block printing, boutique work,

etc. This can be attributed to the limitations

imposed by these dyes, which are as follows:

No assurance of shade repeatability.

Availability of the natural dyes are

limited since they are extracted mostly

from plants which are dependent on the

growing seasons. So it is unlike the

synthetic dyes that are produced in the

laboratories.

Pr esen t ex trac tion process es are

laborious, time consuming and also are

not economical.

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Even though natural dyes produce brightcolours and variety of shades, but tend tofade faster than the synthetic dyes.

Variability in the quality and quantity of

extraction depends upon the age andseason of the plant, tree, leaves or fruitand hence standardization is difficult.

Most dyes need a mordant to fix thecolour. Some mordants used along withnatural dyes may be toxic to some extent.Alum is safer to use, though not entirely

nontoxic.

Synthetic fibers, which are becomingwidely popular can not be dyed withnatural dyes.

Thus, it can be concluded that thoughnatural dyeing is a very old process and has apotentiality to prepare garments with widerange of colours, still further scientific

developments are required in the field to makebetter shades and fast colours and to make theprocess economically more feasible andacceptable by the people.

References:Gulrajani, M. L., Gupta, D B, Kumari A., Jain M. 1993.Natural dyeing and their application in textiles. IIT, Delhi,pp 10-25

Sahoo, T, Bhattacharya, G, Das, P. and Dash, S K. 2014.Effectiveness of sal, Shorea robusta Gaertn.f. bark dye onmordanted silk. Indian Journal of natural products andresources. 5(2): 176-183.

Samanta A K, Agarwal, P. 2009. Application of naturaldyes in textiles. Indian journal of fibre and textile research.34: 384-399.

College of Home Science, OUAT, Bhubaneswar

Mobile : 9438185125

FOOD ALLERGENSDr. BasantaKumarChoudhury

Good health is the state ofcomplete physical, mental, social well beingand not merely the absence of disease orinfirmity. To maintain it, we have to eat a dietcontaining essential nutrients in correctamounts.Abalanced diet is recommended forthis reason. Its amount depends on the sex,age, work schedule etc. of a person. Balanceddiet denotes different types of foods in suchquantities and proportions that the need forcalories, proteins,minerals, vitamins and othernutrients is adequately met. Besides, a smallprovision is made for extra nutrients towithstand short durations of scarcity.Sometimes, the recommended food in thebalanced diet may have adverse impact on aperson. It is manifested in the form of allergy.Food allergy is a form of immunologicre sp onse to speci fic su bs tance wi thcharacteristic symptoms whenever such foodis eaten. It may be defined as altered reactionof the tissue system of the body to foreignprotein or antigen. The substance responsiblefor invitation of allergic reaction is an allergenor antigen. Allergy may be caused due to(a) ingestion of food or drugs; (b) contactwith foods, pesticides, drugs, adhesives,feather or fungi, (c) inhalation of pollens,perfumes, cosme tics, dus ts etc.(d) injections of vaccines, serums, antibodiesand hormones etc. of these food allergy isvery common among the people.

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Symptoms of food allergy

Manifestations of food allergy occur indifferent parts of the body.

1. Skin : It includes cancerous sores,dermatitis, oedema, blisters and rashes.

2. Gastrointestinal disorders : There maybe chilit is, stomatitis, colic in infants,abdominal distentions, constipation, diarrhoea,dyspepsia, and vomiting.

3. Respiratory reactions : Allergenreactions may be manifested in the form ofasthma, bronchitis, and nasal polyps.

4. Neurologic effect s : Ne urologicsymptoms include migraine, neurologicsyndromes like anxiety, fatigue, irritability,muscle and joint pain, restlessness and stomachpain etc.

Food allergens

There are various types of food allergens.As it has been already mentioned, the foodallergens cited below may be nutritions and apart of the balanced diet but causes immediateor delayed responses in the form of allergieson specific persons.

1. Milk : Milk contains two majorcomponents such as carbohydrate lactose andprotein casein which are not easilydigested byall the persons. For digestion of lactose sugar,a specific type of bacteria i.e. Lactobacillus isneeded in the alimentary canal to break it downto glucose. Similarly a specific typeof enzyme,

renin is needed to digest the casein protein.

2. Egg:Egg is the common allergen among

the food items obtained from animals. Skin

reactions occur more frequently than other

symptoms. Egg white intolerance has been

observed among many people.

3. Fish : Allergic symptoms due to

consumption of fish is usually not confined

to a particular species. Generally, allergic

reactions appear very promptly in the form

of rashes, angioneurotic oedema,

dermatitis, gastrointestinal disorders and

even asthma.

4. Meat : Meats of all kinds may have

allergic effect. It has been observed that the

cases of hypersensitiveness to meat of a certain

animal has been observed with some

individuals. However, the liver, pancreas,

Kidney and brain of the same species can be

eaten with no reaction.

5. Cereals : Some times wheat flour has

been associated with allergic reactions with

some individuals. The allergic reactions to the

consumption of rye has been observed in many

patients suffering from hay fever caused by

inhalation of rye pollen. The allergic reactions

disappear when the rye bread is eliminated

from the diet.

6. Soybean : Soya be an ha s be en

recommended for feeding infants allergic to

cow's milk: It isknown tohave low allergenicity

but symptoms do occur in other infants.

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It has been observed that people who are

working in glue factories using soya flour as

an ingredient of glue develop severe allergic

asthmatic symptoms.

7. Peanuts : It has been reported that a

few individuals may be allergic to peanuts

resulting in abdominal pain, skin eruptions and

asthmatic effects.

8. Edible Fungi : Consumption of edible

fungi have been reported to cause allergic

reactions in some individuals. A few cases of

individuals allergic to consumption yeast have

been reported.

9. Vegetables and fruits : Among

vegetables and fruits, carrot spinach, cabbage,

asparagus, celery, onion, garlic, sweet potato,

cauliflower and pumpkin etc. have been

observed to produce allergic reactions. There

are occasional cases where an individual may

be found sensitive to raw but cooked item or

vice versa.

Straw berries, bananas, oranges, grapes

and apple are among the principal offenders.

There are also reports of allergic reactions

due to consumption of pears, cherries, plums,raspberries and goose berries.

10. Beverages :

Alcoholic beverages may cause clinical

manifestations of allergy, of both specific and

nonspecific types. The specific allergic

reactions is due to traces of foreign substances

derived from food materials employed in

preparation or cleaning of the beverage such

as barley malt and yeasts in beer, rye, corn and

wheat in whisky; fish glue, egg white or yeast

in cheap white wine and champgne.

The nonspecific reaction is due to the

effect of alcohol in increasing permeability of

membranes of gastrointestinal tract. Thereby,

the food proteins are incompletely digested.

11. Food contaminants as allergens :The food contaminants may be preservatives,

insecticides, insect excreta or fragments. These

contaminants may act as allergenswhereas the

food itself is harmless such contaminants may

enter our plant food in the field or may enter

during storage, processing and shipping. The

common additives may include colour,

fl avouring mater ial s, preservat ives,

insecticides.

The list mayincrease since the metabolic

pattern may vary from person to person. A

metabolic pattern may vary from person to

person. A patient allergic to a specific food

may avoid it for at least a period of time.After

sometime, the same food, if an important

ingredient of the balanced diet, may be tried

with utmost caution in small amounts. Doctoror dietician advice may be taken here to avoid

serious illness.

Sidhi, 24/732, Shree Vihar, Bhubaneswar - 751 024

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JACK-OF-ALL-TRADES-ANTONY VAN LEEUWENHOEKProf. (Dr.) K. PravakarProf. (Dr.) G. C. Sahoo

I'm well aware that these my writings

will not be accepted by some, as they judgeit to be impossible to make such discoveries:

but I don't bother about such contradictions.Among the ignorant, they're still saying about

me that I'm a conjuror, and that I show people

what don't exist: but they're to be forgiven,they know no better".

-ANTONY VAN LEEUWENHOEK.

Over three hundred years ago, human

racewas beset with ignorance and superstition.Those were the times when the church and the

monarch had tremendous influence on the

freedom and expression of thought. Duringthat period Servetus was burnt alive for

attempting to dissect a body and Galileo wasput behind the bars for attempting to prove that

the earth revolved around the Sun. The peoplepaid little attention to hygiene and cleanliness.

Chamber pots (chamber pot is a round

container that people in the past had in the bedroom and used for urimating at night) were

emptied on the pavements or the streets and

the contents remained there for months toyears facilitating the outbreak of epidemics.

During this period a Dutchman, J Antony VanLeeuwenhoek made some contributions to

dispel the beliefsand misconceptions by laying

bare the unknown concepts to the humankind.Thoughhe wasnot aware of the significance of

his observations, he had sown the seeds of

germ theory.

A certain very understanding gentlemanin our town who had been reading our printed

letters, said to me "Leeuwenhoek, you havegot the truth, but it won't be received in your

life time". In retrospect, Leeuwenhoek did notreceive the acclaim he deserved in his lifetime

though the epoch making observations wereno less significant than that of Pasteur or

Koch. Itcanbe said, "Leeuwenhoek gave us themessage, and Pasteur and Koch showed us the

way, as far as the discipline of bacteriology isconcerned". This is a remarkable contribution

for someone who was a draper by professionand for some one who had no knowledge of

science at all.

Antony van Leeuwenhoek was born on

24 October, 1632 in Delft, Holland in a familyof craftsman of good Dutch stock. His fatherwas a basket weaver and he passed away when

Antony was five years old. His mother married

again and Antony's stepfather was a painter.Antony was sent to school at Warmond, atownship north of Leyden.After receiving his

earliest education at Warmond, he was sent to

live with his uncle who was an attorney andtown clerk at Benthuizen. Antony was taughtMathematics and physical Sciences but he did

not learn any other language, which was

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essential for an entry to a University. At theage of 16 Antony left for Amsterdam to learnthe business of linen-draper and in a short timehe qualified himself as a draper and rose to theposition of book keeper and cashier.After astint as an apprentice for six years inAmsterdam he returned to Delft and there heremained for the rest of his life.

Leeuwenhoek married Barbara and shedied twelve years after their marriage. Shebore him five children of which one femalechild, Maria survived, Maria remained as anunmarried woman and she took care ofLeeuwenhoek until his death. Leeuwenhoekmarried again and his second marriage lastedfor twenty-three years before the death of hissecond wife. There were no surviving childrenof this second wedlock. Leeuwenhoek wasblessed in havingMaria at home whowas loyalto him and extended moral support, love andcare through out his life.

Leeuwenhoek started his career as adraper and made his living out of thisprofession. Apart from his business, he had apost in Delft as "chamberlain of the council-chamber of the worshipful sheriffs of Delft".One other municipal function he dischargedwas as a wine gauger who had to assay all thewines and spirits entering the town and tocalibrate all the vessels of the wine. Being alsoa qualified Surveyor his competence was notconfined to any one particular field and he didjustice to all his duties.

Amidst all his activities and in betweenselling of buttons and ribbons, Leeuwenhoeck

found time in making lenses. He was notsatisfied by lens ground by others. He visitedthe spectacle-makers, spent his spare timewith alchemists and apothecaries to acquirethe art of extracting metals from the ores sothat he could mount his lenses on to the metalframes. He was a man of perfection and setupon himself the job of grinding lenses andmounting them on to metal frames to formmicroscopes. His dedication paid off and hecould grind the best lenses not only in Hollandbut also in Europe.

Leeuwenhoek began to observe variousobjectsand materials that aroused his curiosity.He demonstrated some of his specimens inthe microscopes designed by him for a Dutchphysician Reiner de Graaf and the physicianwas amazed at the findings and the clarity ofthe instrument. Reiner de Graaf before hisdeath at a young age of thirty-two brought thisto the notice of the Royal society of London.Henry Oldenberg, the then Secretary of RoyalSociety of London invited Leeuwenhoek tosubmit some of his observations to the Society.Leeuwenhoek sent his observations promptlyto the Royal Society of London and the firstletter was titled "A specimen of someobservations made by a microscope contrivedby Mr.Leeuwenhoek concerning mould uponthe skin, fish, etc.; the sting of a bee, etc".

Leeuwenhoek did not receive any

assistance from contemporary microscopistsfor it was futile to expect any guidance fromthem since none could match his efficiency in

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makingthose instruments. Moreover, he trustedhis own genius and he resented the companyof others. He was very inquisitive to explorethe tiniestof tiny things innature. Leeuwenhoekcalled themicrobes "wretched beasties". Whencommunicated to the Royal society of hisobservations that a little drop of pepper watercontains innumerable microorganismscomparable to as many men as in his nativeplace, the members of the Royal societyreceived the information with disbelief andsome of the members sneered at his findings.Nevertheless, some wise soulsamong the RoyalSociety commissioned Robert Hooke andNehemiah Grew to build the very bestmicroscope as per the specifications ofLeeuwenhoek and they confirmed that whatLeeuwenhoek had described was true. Themembers of the Royal society were astoundedby the ingenuinity of Leeuwenhoek and invitedhim to become a member of the Royal Societyof London that year.

The Royal Society had a selected groupwith significant achievements as memberswhich included among others Robert Boyle,the founder of the science of chemistry, andNewton. Leeuwenhoekhad the honour of beinga member of this elite group though he was inno way connected to science. Moreover theRoyal Society in its existence except forLeeuwenhoek did not have a haberdashereitherbefore or after him as a member.

For the next fifty years, he sent hisobservations in the form of long rambling

letters to the Royal society and those letterscontained mostly but not entirely of hisobservations but interspread, with remarks of

his health, of his neighbours, of his beliefs andof superstitions. He sent his observations tothe Society in the form of letters and moreletters covering a range of fields that includedzoological, botanical, chemical, physical,

medical and unclassifiable or miscellaneousbut he did not write a scientific paper orpublish a book. Leeuwenhoek was verysensitive and had a fear that his work may notbe received with due recognition and hence

did not undertake any publication. In fact, hehad to bear some critics who were of theopinion that he saw more with his imaginationthan with his magnifying lenses.

Leeuwenhoek was a curious man -Curious about observing the presence of

novelty in any material. This separatedLeeuwenhoek from the so-called learned"scientists" who had trained their thoughts toobserve only the conventional materials orobjects. He was interested in examining

anythingof interest that he laid his hands upon.To cite an example Leeuwenhoek took somescrapings in between his teeth and whenexamined under microscope he found thepreparation teeming with small animalcules.

To his surprise, these small animalculesdisappeared when he took the specimen fromthe same site after consuming a scalding coffee.This led him to infer that these minisculeanimals were sensitive to heat. Further, he

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took the trouble of examining his own faeces

and those of horses and pigeons in amicroscope. He was surprised to find that

there were no animals in the dung of horses

and cows. He had never made any diagram, ora record, or made things public unless he was

sure of what he was observing. His peers

wondered the need for taking so much trouble

and pains at examiningtheunknown. However,Leeuwenhoekwas of the opinion, "But I do not

write for such people but only for the

philosophical."

Through out his life Leeuwenhoek kept

posingquestions at nature andwas enthusiasticin finding some answers to it. He was one

who did not wait for an ideal path to appear

before him for he knew that ideal paths arenot made by waiting but made by walking.

Who would have thought to observe a drop of

rainwater under a microscope? A drop of

blood under a microscope? A drop of semenunder microscope? Not only these but any

material he felt should be examined under a

microscope he examined it in detail for hoursand was fascinated by his observations.

Anything he observed was unknown up to that

period since no one possessed the equipmentor the imagination Leeuwenhoek had to

explore the unexplored. Thus he was awe

struck when he observed that a drop of blood

contained millions of small elements nowknown as RBC , a drop of semen contained

swarming cells like a locust of insects with a

head and a tail, a drop of water from differentsources contained innumerable "wretchedbeasties". And he communicated all hisfindings to the Royal Society.

As the findings of Leeuwenhoek wererecognized and appreciated by many, thosewith an interest to observe the unknown worldof microorganisms made a beeline atLeeuwenhoek's place to have a glimpse of theworldof microbes. This list is longand includeskings, princes, physicians, philosophers, publicofficial, clergyman,peasants and even commonperson. Of notable mention is the interest andcuriosity Peter the great of Russia expressedwhen he observed the preparations ofLeeuwenhoek when he had visited Holland.The Tsar was particularly impressed when heobserved the circulation of an eel in themicroscope, among the many specimens. TheQueen of England evinced a keen interest andwas fascinated by the wonders of nature whenHer Highness observed some specimens undera microscope. While ordinary mortals wouldvery much welcomed such publicity andat tention derived out of such visi ts ,Leeuwenhoek considered these visits by theMonarch and the nobility as an intrusion intohis routine affairs and always preferred to beleft alone.

It must be appreciated that thoughLeeuwenhoek was not a Scientist he had the

humility to discern facts from speculations.For when recording his facts he would recordit as "I have observed" but when giving his

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comments he recorded it as "but 1 imagine" or"I figure to myself. Leeuwenhoek was candid,humble and very simple. According to himtruth and truth alone should be recorded anddisseminated and until his dying dayshe strovetowards this end.

From his eighty fifth year, his healthstarted deteriorating but he still did not give uphis passion for observation of the unknown.Even in the deathbed, Leeuwenhoek wasconcernedabout his observations, to the extentthat he requested his friend, Hoogvliet, totranslate his letters to the Royal Society. Thosewere the last letters to be dispatched byLeeuwenhoek to the Royal Society. Finally,the end came in 1723 at the ripe age of ninety-one years.

Inthe courseofhis lifetime, Leeuwenhoekmade dozens of microscopes and at every

opportunity, he attempted for more perfectionthan the previous attempt. This endeavor gaveLeeuwenhoek the ability to construct the bestmicroscopes of his time. Leeuwenhoek forthe reasons best known to him did not wish topart with his microscopes during his lifetime

to anyone, not even to the Royal Society. Hewas very possessive ofhis equipment. However,he must have realized that unless he makes hiswork public all his efforts during his lifetimewould be invain.Accordingly, as per the wishesof Leeuwenhoek, Maria dispatched a little

cabinet containing the microscopes and thespecimens to the Royal Society within a fewweeks after his death. The members of the

Royal Society were amazed at the quality ofthe microscopes and all his microscopes werepreserved in the Royal Society of London.However, a century later all those microscopesdisappeared mysteriously.

Todaythe contributions of Leeuwenhoekmay seem to be ordinary, but if we move intothe time capsule of Leeuwenhoek, thecontributions made by him were phenomenaland remarkable. In the present time, thefacilities available such as electronic mail andmobile phone for rapid communication and airtravel for rapid transport are taken for granted.But what of those times when messages weresent by pigeons and Bullock cart and horsedrawn carriages were the onlymode of transport.Likewise, during Leeuwenhoek's period thebest magnifying equipment was only the handlens. Leeuwenhoek not only constructed thebasic microscopes but also entered deep intothe quest of nature through his microscopes.Helaid the foundationofthe field ofbacteriologyand could be considered the first among themicrobe hunters. More than a century after thedemise of Leewenhoek, it wasAugastino Bassian Italian scientist who first incriminated themicroorganisms in an infectious disease -Muscardine, a disease of silkworm thusindirectly attaching the significance ofLeeuwenhoek's observations. There is alwaysa place for Antony Van Leeuwenhoek in the"Hall of Fame" of Medicine.

Department of ENT, Head & Neck Surgery,

Rajah Muthiah Medical College & Hospital, AnnamaliUniversity, Annamalainagar - 808002, Tamilnadu

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OCTOBER,2014

SAY NO TO E-CIGARETTES TOO!Dr. Guru Prasad Mohanta

While realizing the harmful effects of

cigarette or tobacco smoking on human healththe World Health Organization this year

advocated increasing the taxes on tobacco toreduce their use. It says the raising tax is themost cost effective way of reducing tobaccouse. In the current budget with the same

philosophy, the Government proposed heftyhike in taxesranging from11% to 72% makingcigarettes costlier and discouraging the people

from smoking. Though it is yet to see whetherthis would be successful in reducing thetobacco consumption and improves the healthin reducing the tobacco related harms. There

has been continuing promotion of electroniccigarettes as tools helping smokers to quittobacco smoking. With several conflicting

reports appearing in the media and press itraises concern bythecommon man on its safety.

Recently e-cigarettes are under seriouscriticism. Experts of the WHO called for a ban

on the use of e-cigarettes indoors and alsocautioned against these being sold toadolescents in fruit, candy or alcoholic-drinkstyle flavours, which would increase its wider

use in children.The experts also said there wasstill no strongevidence tosupport the claims thate-cigarettes couldhelpsmokers toquit smoking.

Electronic cigarettes , also called

e-cigarettes, are battery-operated nicotinedelivery devices resembling tobacco cigarettes.

Smoking ane-cigarette is called 'vaping' because

the device producesa vapourcontainingnicotine,which is inhaled by the user. The origin of

electronic cigarettes goes back to China in1963 when a Chinese pharmacist, Herbert A.

Gilbert, obtained patent for device, a smokelessnon-tobaccocigarette. It took almostforty years

to make the first marketable device available.This was first introduced in 2004 to the Chinese

market as an aid for smoking cessation andreplacement. Since thenthere are manyvarieties

and developments. E-cigarettes command anestimated global business of 3 billion dollars

with almost 466 brands in the global market.

E-cigarettes consist of three basic

components: mouth piece and two interlockingplastic tubes. The distal tube is a rechargeable

battery. The proximal tube is a cartridge. Thecartridge contains a heating element and a

reservoir of liquid nicotine. Some modelsalso have an LED light at the tip that glows

when the device is in use giving an appearanceof lit cigarette. The liquid present in the

cartridge is a mixture of propylene glycol,and/or polyethylene glycol (PEG) and/or

glycerin and liquid nicotine. They are madeavailable with various flavours like tobacco,

mint, coffee, cherry, bubblegumand chocolate.The nicotine contents of e-cigarettesvary from

no nicotine to high level of nicotine. Howdoes an e-cigarette operate ? As the user

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OCTOBER,2014

inhales through a mouthpiece, air flow triggers

a sensor that switches ona smallsafely operatedheater. The heater vapourizes liquid nicotene

in a small catridge which also contains thePEG and that gets vaporized by the heater

giving out theatrical smoke. The user gets apuff of hot gas that feels a lot like tobacco

smoke. When the user exhales, there's a cloudof PEG vapour that looks like smoke and

which quickly dissipates.

The recent findings of the Centre for

Disease Control and Prevention,USA, reportedmany fold increase on poisoning cases over

the last few years associated with use ofelectronic cigarettes. This has raised serious

concern on the safety of these products. It hasbeen reported that number of calls to poison

centres in United States has increased fromone per month in September 2010 to 215 per

month in February 2014. At the same timethere is no significant change in the number

of poisoning cases reported due toconventional cigarettes. But what causes more

alarming is that more than half of the calls

were related to children under five. The

Centres for Disease Control and Prevention isone of the major operating components of the

Department of Health and Human Servicesmandated to protect the people of America

from health, safety and security risks. Theliquid in e-cigarettes has added chemicals but

the exact nature of the chemicals are notknown or disclosed by the e-cigarette

manufacturers. The study report shows thatthey are not emission free and their pollutants

could be of health risk.

There hasbeen increasing advertisements

for promoting e-cigarettes as a safe means todeliver nicotine without the array of

carcinogenic compounds found in cigarettes.At the same time, there has been considerable

health concern as there is no conclusiveevidence that these smokeless inhalation

systems are less harmful than the conventionalcigarettes. Recent research has also shown

that the e-cigarettes could act as a steppingstone to real cigarettes and drug addictions for

impressionable minds of the adolescents. InUSA the use of e-cigarettes by children and

teenagers has doubled in the last two yearssignaling danger of using them as gateway

products. They would become smokers later.One must opt for Healthy Choice though this

is difficult. One must muster courage to sayno to e-cigarettes too as a healthy choice!

Professor, Department of Pharmacy, Annamalai University,

P. O. Annamalai Nagar, Tamil Nadu - 608002E. mail: gpmohanta@hotmail.com

ScienceHorizon28

OCTOBER,2014

MAKE YOUR OWN HYDRAULIC LIFT MODELNikunjaBihariSahu

From the backyard log splitters to thehuge machines you see at construction siteslike bulldozers and cranes , hydraulicequipments are amazing in strength and agility!Many elevatorsare hydraulically operated andmost aircrafts use hydraulics in their brakingsystems and landing gear. The brakes in yourcar also use hydraulic device. Hydraulicsystems are commonly used in automobileservice centres to lift our cars for mechanicsto work beneath them.Have youever wonderedhow does a hydraulic machine work? Let'smake a Hydraulic Lift model capableof raisinga small load to understand the principle.

The basic idea behind any hydraulicsystem is very simple: Pressure (Force perunit contact Area) applied at any point of thesystem is transmitted equally in all directions.Using a closed incompressible liquid, thetransmitted pressure can be made to be releasedover a larger area at the desired locationproducing a greater Force. This remarkableproperty of transmission of pressure in liquidswas discovered by a French physicist BlaisePascal in the year 1653.

What You Need

Disposable (Plastic) Injection Syringe - 2nos (10 ml and 50 ml capacities), Plastic tubeused in aquariumpumps, Plywood sheet (Size:8" x 4" x 6 mm thickness) - 2 nos (One of thesheets should have two holes at 3" distanceapart wide enough to allow both the injectionsyringes to enter), Wooden batten (Size: 8"height x 1" x 1") - 2 nos. and some Iron nails.

How You Make

Prepare a Wooden stand to hold ourDispo-vans steady. For this, take the plywoodbaseboard (the one without having any hole)and fix the two wooden battens vertically onits two sides with nails. Fix the holed ply-wood piece at the top of the wooden battensparallel to the base-board. Slip the two Dispo-vans into the respective holes,.so that theyhang vertically down, securely. Fill both theDispo-van cylinders with water up to half oftheir capacities. Fill the plastic tube completelywith water. Connect the two ends of the tube toboth the nozzles of the Dispo-vans avoidingany air bubble. Now, our Hydraulic Lift kit isready for use.

How You Go

Put a heavy object like a book on thepiston of the larger Dispo-van (50 ml capacity)cylinder. Press the piston of the smaller Dispo-van (10ml capacity) cylinder with handsgently.The pressure is transmitted through water inthe connecting tube and acts upon the largercross-sectional area of the other piston (50 mlcapacity). Due to the large contact area, theforce is multiplied many times (almost thrice)on the larger Dispo-van. Thus the book can belifted up easily.

LIG 12/11, Arya Vihar,

P.O.-Sailashree Vihar, Bhubaneswar-751021Mobile : 8018708858

29ScienceHorizon

OCTOBER,2014

PLASTIC LOW TUNNEL TECHNOLOGY FOROFF-SEASON CULTIVATION OF CUCURBITS

Dr. Nityamanjari Mishra

Vegetable cultivation in off season is agamble with thenature. The growers, for gettinghigher prices for these produce, often try tosend it to the market either early or late in theseason. They want an extended growing seasonforselected vegetablecrops to obtain maximummarketing advantage ignoringthe perishabilityof the produces. For example, crops like longmelon, round melon,bottle gourd, bitter gourd,muskmelon, summer squash etc., if grownearly either in spring or in summer oftencommand a greater price in the market. Alsowhen larger supplies of the produce are notavailable (considered as "offseason") it maycause price inflation due to increased demand.

Presently, river bed cultivation is inpractice for production of cucurbitaceousvegetables in northern parts of our country,although area under river bed cultivation isvery limited,which cannotbe extended further,but with the use of protective structures suchas row covers or low tunnels vegetable cropslike muskmelon, watermelon, long melon,round melon, bitter gourd, bottle gourd,summer squash etc. can be grown very earlyeven in the winter season. Important factorswhich are considered for off season cultivationare 1) increased costs of using season, extenderproduction systems, 2) potential increase insale prices of the crop if produced eitherearlier or later, 3) suitability of the crop to

season extender production systems. The useof plastic low tunnels for off-season melonsand summer squash production is a commonpractice in Israel for export of the produce toEuropean countries.

Row covers or low tunnels are flexibletransparent covering that are installed over therows or individual beds of transplantedvegetables to enhance plant growth by warmingthe air around the plants in the open fieldduring winter season. They can also warm thesoil and protect the plants from hails, coldwind, injury, and advance the crop by 30 to 40days than the normal season. This low costtechnology for off season cultivation ofcucurbits like muskmelon, round melon, longmelon, bitter grand, bottle gourd and summersquash etc., is suitable and may be quite costeffective for the growers in the interior partsof ourstate, where the night temperature duringwinter season goes below 8°C for a period of30-40 days. The major steps involved in thistechnology are as under:

Basic requirements:

Selection of seeds: It is imperative to

have better quality seed possessing geneticcharacters suited to the environment in whichit is grown. Good vegetable seed must be true-to type, viable, disease- and pest-free, freefrom weeds, dirt and other foreign materials.

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Selection of cultivars: Cultivars suitablefor open field condition are usually suitable

for polyhousecultivation. But relatively rapid-

maturing cultivars and high-yielding hybrids

are ideal. The selection of cultivars and hybridsdepend onplant typeand their growthbehaviour.

Thecucumber cultivars should be unique. They

should have only female floweringhabit, withdark green parthenocarpic (seedless) fruits

free of bitterness.

Nursery raisingfor off-seasoncultivationof cucurbits

Seedlings of the desired cucurbits are

raised in the greenhouse nursery in plastic

pro-trays having 1.5" cell size with soil-less

media in the month of December or Januaryand 28-32 days old seedlings at four leaf

stage are transplanted under row covers or

plastic low tunnels in the open field frommid January to mid February, when the night

temperature is very low in the interior

districts of our state. Nursery of these cropscan also be raised even in polythene bags

under very simple and low cost protected

structures like walk-in tunnels or in locally

available plastic trays with soil less mediaas per the need of the area. Crops like

summer squash can be transplanted even in

the month of December for completeoffseason production and this crop will be

ready for harvesting in the first week of

February which can fetch a very high price inthe market.

Preparation of beds, fixing of hoops,transplanting of seedlings and coveringof plastic

Transplantingof the seedlings is done in

a single row on each bed at a planting distanceof 50cm with drip system of irrigation.

Distance between the rows in usually kept 1.5

to 1.6 metre. Before transplanting of the

seedlings on beds, flexible galvanized ironhooks are fixed manually at a distance of 1.5

m to 2.5 m. The width of two ends of hoop is

kept 40-60 cm with a height of 40-60 cm

above the levels of the beds for covering the

plastic on the rows or beds for making low

tunnels.Transparent,30micron, IRgradeplasticfilm is generally used for making low tunnels,

which reflects infra-red radiation to keep the

temperature of the low tunnels higher than

outside. Now-a-days with the introduction ofbiodegradable plastic for making low tunnels

and for mulching purposes, the technology

has not only become eco-friendly but also

sust ainable fo r of f season vegetab le

production. This biodegradable plastic is

available according to the duration of thecrop. After use,the plastic film becomes

brittle due to sufficient sunlight. The.film

eventually breaks down into small flakes and

finally decomposed in the soil. The plastic isusually covered in the afternoon after

transplanting the desired vegetable like

muskmelon, summer squash, bottle gourd,

bitter gourd, round melon, cucumber etc. The

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plastic can be vented or slitted during the

growing season as the temperature increase

within the tunnel during the peak day time.

Generally, 3-4 cm size vents are made on

eastern side of the tunnels just below the top

at a distance of 2.5 to 3.0 m after transplanting,

and later on the size of the vents can be

increased by reducing the distance between

two vents with the increase in the temperature

and ultimately the plastic is completely

removed from the plants in the month of

February and March depending upon the date

of transplanting growth of the crop and

prevailing night temperature in the area.

Fertigation and ptant protection in lowtunnel (muskmelon crop )

Fertilizersareapplied throughdripirrigation.During the first month (i.e. January or February)

water can be applied @ 4.0 m3/1000m2 at aninterval of 6-7 days. After making fertilizersolution of N: P: K (5:3:5) is applied @ 80-

100 ppm per cubic meter of water. Duringsecond month 4.0 m3 of water can be applied

on duration of 4 days with fertilizer solution@ 120-150 ppm till beginning of flowering inthe crop. Thereafter the fertilizer quantity is

reduced to 20-30 ppm till the fruits are oflemon size after which the quantity is again

increased to 120-150 ppm per cubic meter ofwater. Before the ripening of the fruits, thequantity of fertilizer solution is again reduced

to 50-60 ppm for enhancing the quality offruits in muskmelon. But in other cucurbits

the quantity of fertigationisalways in increasingorder, starting from 50 ppm to 300 ppm at thepeak fruiting period. The water and fertilizers

requirement of crops usually depends uponthe growing season, crop and variety and soil

conditions. If required systemic insecticideslike Imidachloprid@ 2ml/l can be applied

through drip irrigation water for control ofinsects at early stage of crop growth. Whenthe crop is under plastic tunnels no foliar

spray is possible.

Harvesting and crop advancement

If the muskmelon crop has beentransplanted in first week of February the

Fig-1 : Low tunnels for off-season vegetable cultivation

Pollinationunder plastic low tunnel crops

Most of the cucurbits are monoecious in

sex form and entomophills, which is usually

performed by honeybees (Apis melifera). At

full blooming stage bees can work in tunnels

easily through the vents, made on the plastic.

For effective pollination in crops like

muskmelon, summer squash etc, one beehive,

having 30000-50000 workers is sufficient for

one-acre area. The beehive box is always kept

on the northwest side of the field for effective

working of the bees.

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OCTOBER,2014

fruits will be ready for harvesting in third

week of April. Fruits from the mid January

transplanted crop can be harvested in the

first week of April, which is normally 30-40

days earlier than the normal season. Similarly

other cucurbitaceous crops can be advanced

40-60 days earl ier than the normal season

of growing under low tunnels in the interior

districts ofour state. Crops like summer

squash can be transplanted in the first week

of December, which are ready for harvesting

in the first week of February, and can be

treated as off-season crop. Diff erent

cucurbits can be transplanted from first week

of December to first week of February and

can be advanced 30-60 days over their normal

season of cultivation (Table 1). Off-season

fruits produced under low tunnels can fetch

very high price in the market. This

technology is quite economical for growing

off-season vegetables in peri-urban areas of

ourstate and the country.

Table 1: Transplanting, crop advancement and expected cost benefit ratio in cucurbits.

Sl. Crop Transplanting time Harvesting time Crop ExpectedNo. advancement cost benefit

ratio1. Summer First week of First week of 60 days 1:3 to

squash December February 1:4

2. Muyskmelon Third week of Second week of 30-40 1:2.5 toJanuary to first April to last week days 1:3.5week of February of April

3. Bottle gourd Third week of January Second week of 30-40 1:2.5 to

to first week of April to last week days 1:3.5February of April

4. Bitter gourd Third week of January Second week of 30-40 1:3 toto first week of April to last days 1:4February week of April

5. W. Melon Third week of January Second week of 30-40 1:2 toto first week of April to last week days 1:2.5February of April

6. Cucumber Third week of January to First week of 30 days 1:3 to

first week of February February 1:4

Senior Research Fellow, AICRP on Integrated Farming System, OUAT, Bhubaneswar

33ScienceHorizon

OCTOBER,2014

THE WORLD OF AKASHSri Soumendra Ghosh

The day Monica and her new born babyarrived from the outer space at the obscurelanding port in the pacific, a small crowd waseagerly waiting to have a close look at the firstspace born human. The crowd of course knewall about the birth of the child. They had seenthe baby on giant T.V. screens and watched allits movements. Yet they came with allexcitement to be the first to actually see thebaby, a new milestone for mankind. Theyincluded reporters, scientists associated withthe project and Monica's near and dear ones.For three hundred and twenty six days Monicawas upthere in the spacecraft that was hoveringaround the earth in its geostationary orbit.

From the recovery vessel Monica withher baby were driven directly into a quarantinechamber. Through the glass panes of theChamber, Monica waved her hand. From adistance through the glass, Monica with herspace suit resembled a robot, but for themissing head gear and beaming with missionaccomplished smile. The smile on her faceclearly showed the immense satisfaction ofbeingthe first ever spacemother on our planet.Monica was carrying her baby as a mostprecious possession. Smile is infectious. Itspreads. Monica's smile made the scientistssmile; they were hugging each other, shakingtheir hands. Others who came to witness theevent were also smiling having been the firstto have glancd the brave new world, openingyet unknown frontiers in the uncharted waters.

Before the wave of smile receded, Monicaentered the attached living room.Alone in theisolated room Monica freed herself from thespace suit, released the baby from a speciallydesigned outfit. Baby in his birthday suitwrinkled his face and Monica's heart melted.Like all new mothers Monica couldn't believethat the baby was really a part of her, made withher own flesh and blood. Tears flooded hereyes. Afeeling of completeness enveloped her.

The next moment, Monica fe ltdisheartened. She sighed. She knew that aftershe was through with the quarantine, scientistswill take away the baby from her. After all,Monica was just a surrogate mother - a motherwho only lends her womb to bear a child.Monica was selected by the scientists aftercareful scrutiny. The advantage for Monicawas that she had past experience of staying formonths in the space, and belonged to thefraternity of space explorers. Besidesbiologically Monica was found to be mostsuitable to discharge this unique responsibility.

Monica recalled the day when she wasmade to conceive. When Doctors started theprocedure, other scientists were around her.She could listen to the conversation across thescientists and Doctors. A young scientistobserved that Monica, during her stay in thespace, will be required to spend time outsidethe spacecraft for three to four hours a day(when she will be) in an antigravity state.Unknown cosmic and other rays could

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OCTOBER,2014

penetrate the developingfoetus. There may bemutations. The senior scientist responded witha smile, "thats' what we are going to observe;lets see how the developing embryo copeswith the new conditions."

After pushing the fertilized egg to its sitethe Doctor said, 'Ihave done my best, lets keepour fingers crossed for another seven days.

The egg was successfully implanted.Everything went on smoothly as per schedule.Monica lefton her epic journey. Three hundredand twenty six days in a space craft turned outto be a gruelling ordeal indeed. Everyday sheattended to all the chores, according toinst ruct ions. Monica's different bodyparameters, the developmental pattern of thefoetus were closely monitored fromthe groundstation.As weeks passed by Monica could feelthe presence of the foetus developing in herwomb, stirring up unknown emotions - a novelexperience of a new mother to be.

The baby cried. Monica strirred out ofher wanderings. She took the baby in her lap.Smiling generously she patted the baby.

In the evening Monica opened her mailbox. Thanked all her well wishers. Earlierwhen she came to learn that it would be a babyboy, she had tweeted for a suitable name forthe boy. Her growing list of followers hadsuggested thousands of names, some verycommon some uncommon. Monica wasintrigued by the name 'Akash'. She looked forthe meaning of the word wikipedia aid 'Akash'a Sanskrit word meaning ether - the basis andessence of everything in the material world.

The first material element created from theastral world. In many Indian languages themeaning of Akash is sky". Monica liked thename as most appropriate. The baby waschristenedAkash son of a single parent born inspace of unknown father.

After the quarantine scientists startedworking on var ious physiological andbiochemical parameters of the baby. Resultsthankfully showed no abnormalities. Aftergenome analysisand DNAsequencinghowever,some major changes were noted in the DNA ofAkash. They foundsome genesotherwise silentin normal human being, were demethylatedwhich meant they were active now. Serumprotein analysis found some new bands whichindicated that Akash was synthesizing somenew proteins. Not knowing the role of thesenew proteins scientists had no other optionsbut to wait and watch. Meanwhile,Akash grewup with the passage of time.

Pages from Akash's diary

To-day my class teacher asked me not toparticipate in the inter class quiz competition,saying politely that other studentswould object.I know if I participate, no one could win. Samething was repeated during annual sports. WhenI joined for the first time I became the allround champion, winning all the medals. Nextyear again I repeated my feat. Now they don'tallow me to participate. What can I do ifothers don't match up to me ? I can see more,listen better than others. My memory is sharp,I can solve complex problems in minutes. Isthis my fault ?

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I knowI amdifferent frommyclassmates.Why only classmates, I am different fromevery body on this earth. They call me 'superman'. I have read 'Superman' comics. I likesuperman. He is like me. I have strength andstamina. The only difference is that I cannotfly. While superman had a scientist father, Idon't know who is my biological father evenmy motherdoesn'tknow. In mybirth certificateonly my mother's name is mentioned. Mymother loves me. She only understands myfeelings. Now that I can read mind, I know mymother is worried about me and my failure.She is unhappy with the scientists. She feels Ibecame different from others because of theexperiments done on me. Now they aremapping my brain. They don'tknow I can readtheir mind. If I don't tell them they cannotknow what I have in mind.

I want to have a friend who can share myfeelings, but I don't have one. Boys are jealousof me, girls stare at meas if I aman alien. Eldersappreciate my extra-ordinary ability; pat myback.Ihavereadtheirmind.Theyonlysympathizeme. I don't understand why they pity me.

I can sense that scientists are nowplanning to develop my clones. They have mystem cells with them. In near future my clonemay see the light of the day. Right now theethics committee is not giving the permission,so they have stopped the venture.

I don't know why these scientists areplaying God. They don't know that they aremeddling with matters foolishly which they

have not understood properly and over whichthey don't have necessary control.

Monica's open letter to the scientists

Thank you for the invitation. I am happyto know you people are celebrating Akash's25th birthday. You take pride on Akash. Youmade him a celebrity from his birth.

I believe that biologically Akash hascome upto your expectations. The 'mutations'in his DNA made him a 'superman'. He isdifferent fromothers.As a mother I understandhis feelings. He is a loner. I feel sad when helooks at the sky with a blank face.

A few days back he questioned me whyI agreed to your proposition, to have a child inthe space. I had no answer to that. Now I feelit was wrong on my part to have kept quiet.

For the last twenty five years Akash hassuffered public glare as an object ofexperiments. He has no privacy, no life of hisown. Being a 'superman' in movies is differentfrom being a superman in real life. I don'tknow for how many more years Akash has tobear the burden of being a 'superman'.

Enough is enough, I guess the time hasnow come to release him from being a subjectof any further experimentation. Akash is aunique gift of the Universe to the mankind, yethe is a son of our mother Earth. Please free himso he can serve as a bridge between the earthand the Universe and inspire future generationto make the whole Universe their family.

D.P. Lane, Bakharabad, Cuttack-2

Mob. : 09437319307

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OCTOBER,2014

LED - TWENTIETH CENTURY ELECTRIC BULBEr. MayadharSwain

The invention of electric bulb is animportant event in the history of science.Thomas Alva Edison of the United States ofAmerica and Joseph WilsonSwan of the UnitedKingdom independently invented the electricbulb in 1879. Soon after, it turned out to beone of the main uses of electricity. Now about25% of electricity generated worldwide isbeing utilized for illumination. The electricbulb invented by Edison and Swan is calledincandescent bulb and it is largely used evennow. It consists of a glass bulb with a tungstenfilament inside it. When current flows in thefilament it gets heated and light is emittedfrom it. The bulb is filled with an inert gasmixture consisting primarilyof argon to protectthe hot filament from oxidation. In this bulb,about 5% of electricity is converted to lightand the rest are wasted as heat.

After this, fluorescent light (generallyknown as tube light) was invented by P. CooperHewitt of the USA in 1900. The familiarfluorescent light consists of a long narrowglass tube with two electrical connections oneach of the metal caps which seal the ends ofthe tube. The tube is filled with noble gasessuch as argon, and a few drops of mercury isplaced in the tube. When electric voltage isapplied across the tube, an electric current inthegas excitesmercury vapour which producesshort-wave ultraviolet light that then causes aphosphor coating on the inside of the bulb to

glow. In this case, about 20% of electricity isconverted to light.

Fromabove, it is evident that in these oldtechnologies, a major portion of electricity iswasted without doingany work. Further, fossilfuels like coal, petroleum oil and natural gasare being used for about 50% of electricitygenerated worldwide (for India it is 69%).After burning, these fuels emit carbon dioxideto the atmosphere. Carbon dioxide is agreenhouse gas and is the main culprit for theglobal warming and the consequent climatechange. Taking this into view scientists andresearchers have now invented an efficientelectric bulb. This is LED.

Three scientists have played important

role in inventing LED. They are ProfessorIsamu Akasaki and Professor Hiroshi Amanoof Nagoya University, Japan and ProfessorShuji Nakamura of California University, USA.The former two scientists are Japanese citizensand Professor Nakamura is Japan-born

American citizen. For this invention, the threescientists have been chosen for award of NobelPrize for Physics in 2014.

LED

The full form of LED is Light EmittingDiode. Diode is an electronic componentmade from semiconductors. It is generallyused in all el ec tronic machines andinstruments such as radio, television,

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computer, mobiles phone etc. These scientistshave developed a way to get more light usingless electricity by using diode.

Unlike general electric bulbs, LEDconverts electricity directly into light withoutconverting it to heat.As a result, less electricityis required for this. For comparison, from onewatt of electricity 16 lumen (lumen is a unit oflight) of light is emitted from incandescentbulb and 70 lumen is emitted from fluorescentbulb, but LED emits 300 lumens of light fromsame amount of electricity. Further, the lifespan of LED is much more than other electricbulbs. For example, life spans of incandescentand fluorescent bulbs are 1000 hour and 10000hour respectively, but the life span of LED is100000 hour. Of course, the cost of LED ismore than other bulbs. But there is saving ofelectricity here and accordingly electric billbecomes less.

A light emittingdiode consists of severallayers of semiconducting materials. On oneside there are n-type layers with a surplus ofnegative electrons and on the other side thereare p-type layers with an insufficient amountof electrons, also referred to as a layer with asurplus of positive holes. Between them is an

Principle of LED

active layer. When an electric voltage is appliedto the semiconductor, the negative electronsand the positive holes are driven to the centralactive layer where they recombine and light iscreated. The wavelength of light dependsentirely on the semiconducting material used.The LED is no larger than a grain of sand.

History

The first report of electrically generatedlight by emission from a solid-state devicecame from Henry. J. Round, a co-worker ofGuglielmo Marconi, Noble prize winner forphysics in 1909 and inventor of radio. Later

on, in the 1920s and 1930s, Oleg V. Losev ofthe Soviet Union, studied it closely. However,Round and Losev failed to understand thephenomenon properly.

Red and green light emittingdiodes weredeveloped in 1950s. These are being used indigitalwatches andcalculators, or as indicatorsof on / off status in various appliances. Butblue light emitting diodes could not bedeveloped. Only the triad of red, green andblue can produce the white light. Despite thegreat efforts undertaken in the researchcommunity as well as industry, blue lightremained a challenge for three decades. Thethree Nobel Laureates were successful indeveloping the blue light emittingdiode whichrevolutionized the lighting technology. Theyworked hard, built their own equipment, learntthe technology and carried out number ofexperiments. The problem was to identify theproper semiconductor material for the diode

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which can create blue light. Finally they foundout the proper material for the purpose. This isgallium nitride (GaN).

Works of the Nobel Laureates

In 1986, Akasaki and Amano were thefirst to succeed in creating a high qualitygallium nitride crystal by placing a layer of

aluminium nitride on a sapphire substrate andthen growing the high quality gallium nitrideon top of it. Afew years later, at the end of the1980s, they made a breakthrough in creating ap-type layer. In 1992 they were able to presenttheir first diode emitting a bright blue light.

Nakamura begandevelopinghis blueLEDin 1988. Two years later, he too, succeeded increating high-qualitygalliumnitride. He foundhis own clever way of creating the crystal byfirst growing a thin layer of gallium nitride atlow temperature, and growingsubsequent layersat a higher temperature.

The LED lamp developed by the NobelLaureates consists of several different layersof gallium nitride. By mixing in indium andaluminium, they succeeded in increasing thelamp's efficiency.

White LED lamps can be created in twodifferent ways. One way is to use blue light to

excite a phosphor material so that it shines inred and green. When all the three colourscome together, white light is produced. Theother way is to construct the lamp out of threeLEDs, red, green and blue, and let the eye dothe work of combining the three colours into

white. Both of these technologies are used intoday's high-efficiency white light sources.LED lamps using former technology are

getting cheaper and the market is currentlyexploding with it. The LED lamps using lattertechnology will surpass the former soon asthis technology allows for dynamic controlof colour composition.

Applications

LED has revolutionized illuminationhistory. It has begun replacingthe conventional

incandescent and fluorescent lamps in theindustry. In due course, it will completelyreplace them even in domestic sectors. It is anenergy-efficient lamp and will help in solvingthe energy crisis in the world in some way. The

great benefit of LED lamps to human societyis the large saving of electricity which in turnhelps in the protection of our environment andsaving of natural resources. Due to low powerconsumption, LED can also be powered by

cheap local solar power.

LED lamps are flexible light sources.Millions of different colour can be producedand the colours pattern and intensity can bevaried as per choice. Everything can becontrolled by computers. Hence LED lamps

can reproduce the alternations of natural lightand follow our biological clock. Greenhousecultivation using artificial light from LED isalready a reality.

The three scientists also joined forcesto build a blue laser, which had at its heart a

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blue LED. Because blue light has shortwavelength, it can store far more informationthan other colours. The increased storagecapacity allowed by blue LED quickly led tothe development of blu-ray discs (a digitaloptical disc data storage format designed tosupersede the DVD format).

The invention of the blue LED is justtwenty yearsold, but it has already contributedtocreatingwhite light in an entirely new mannerto the benefit of us all. Incandescent andfluorescent bulbs lit the 20th century, but 21stcentury will be lit by LED lamps.

The Three Noble Laureates

1. Isamu Akasaki (Japanese citizen). Heis born in 1929 in Chiron, Japan. He hasdone his Ph.D. in 1964 from NagoyaUniversity, Japan. He is now working as

professor at Meijo University, Nagoya,Japan and also as distinguished professorat Nagoya University, Japan.

2. Hiroshi Amano (Japanese citizen). Heis born in 1960 in Hamamatsu, Japan. Hehas done his Ph.D. in 1989 from NagoyaUniversity, Japan and is now working asprofessor there.

3. Shuji Nakamura (American citizen).He is born in 1954 in Ikata, Japan. He hasdone his Ph.D. in 1994 from Universityof Tokushima, Japan. He is now workingas professor at University of California,SantaBarbara, USA.

References

The Nobel Prize in Physics 2014 - TheRoyal Swedish Academy of Sciences - www.nobelprize.org/nobel _ prizes / physics /laureates / 2014.

Deputy General Manager, PP & EE Section,

MECON Limited, Ranchi-834002Ph:- 09470193755, E-mail: mayadhar2002@yahoo.co.in

IsamuAkasaki Hiroshi Amano Shuji Nakamura

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GRID CELLS, PLACE CELLS AND NAVIGATION:2014 NOBEL IN PHYSIOLOGY/MEDICINE

Professor NirajK Tripathy

Nobel Prize foroutstanding contributionsfor the benefit of mankind in the fields ofPhysics, Chemistry and physiologyor medicinehas been awarded to distinguished scientistson 10 December (the death anniversary ofAlfred Nobel, the inventor of dynamite) every

year since1901 bytheRoyalSwedishAcademyof Sciences, the Nobel Assembly at KarolinskaInstitute, the Swedish Academy, and theNorwegian Nobel committee. This prizeincludes prize money, a diploma and a goldmedal. This year's prize for physiology or

medicine has been awarded jointly to JohnO'Keefe of University College, London, May-Britt Moser of Centre for neural Computation,Trondheim, Norway and Edvard I. Moser ofKavli Institute for Systems Neurosciences,Trondheim, Norway. O'Keefe holds British

andAmerican citizenships, where as Edvard I.Moser and May-Brith. Mosers are NorwegianCitizens and also happens to be the husbandand wife and one of 71, 52 and 51 years oldrespectively. O'keefe was awarded half of the8m Swedish Kroma (around £ 700,000 or

around Rs. 336.87 lakh) prize while the othertwo wineers received a quarter each. Thisyear's Nobel Laureates have made seminalcontributions pertaining to the discoveries ofthe cells that constitute a positioning systemin the brain and understanding the brain map ofour surroundings and help us to navigage ourcomplex environment. Their discovery of thebrains "inner GPS" shows that higher cogniticfunction has a cellular basis.

Dr O'Keefe's break through work startedin 1971 when he discovered the firstcomponent of the positioning system whichmade him to win the prize. While he wasrecording the electrical activity of individualnerve cells in the hippocampus of rat's brain,he observed some cells, which were quietmost of the time, became active whenever theanimal was in a particular place in the room.And when the rat was in other parts of theroom. Other nerve cells become active. Heconcluded those cells as place cells. This wasthe first indication that there is a specificrelationship between the geography of theoutside world and the geography of an animal'sbrain. The next vital component of the innerGPS system of the brain came to light overthree decades later in 2005, when Edvard andMay-Brith Moser identified another type ofnerve cell - which they called "grid cells' -Located in the entorhinal cortex region of theJohn O'Keefe May-Britt Moser EdvardI.Moser

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brain, that act as a coordinate system thatenables precise positioning and pathfinding.These cells are arranged in a hexagonal gridwhile the place cells seem to be distributedhaphazardly. The Mosers expanded onO'Keefe's work in 2005 after discovering thegrid cells precisely involved in spatialnavigation. These cells were activated whenthe rats moved through paths. The hexagonalgrid cells work together with place cells toform a comprehensive positioning system thathelps for recognition and navigation ofenvironments. Although their discoveriesoccurredwhileworkingwithrats inthelaboratary,more recent research with brain imagingtechniques, as well as studies of patients whohave brain surgery, have shown that the humanbrain also has place and grid cells.

Place Cells

These cells were first discovered in thebrain, and specifically in the hippocampus, byO'Keefe and Dostrovsky in 1971. Theyreported spatial receptive fields in complex-spiking neurons in the rat hippocampus.Although it is well known that this part of the

brainplaysa major role in learningandmemory,the existence of place cells within thehippocampus shows that it plays a role withspatial adaptation and awareness. O'Keefe andDostrovsky demonstrated that the place cellsin the brain of rats fire when the animal was

within a certain place in theenvironment. Theyalso discovered that space cells fired indifferent areas of the hippocampus depending

on where the rat went, and this whole firingnetwork made up the rat's environment. In1998 O'Keefe and Nadel have found that spacecells would fire more rapidly when rats ranpast places in the environment. A place cell isa type of pyramidal neuron located within thehippocampus of the brain that becomes activewhen the animal enters a particular place in theenvironment. This place is known as the placefield. A given place cell will have only one ora few place fields in a small laboratoryenvironment and more such fields in a largerenvironment. It has been shown that placecells tend to fire quickly when a rat enters anew open environment. However, outside thefiring field these place cells tend to berelatively inactive. These cells are thought toact collectively as a cognitive representationof a specific location in space, known as acognitive map. The firing patterns of placecells are often determined by external sensoryinformation and the local environment. Thesecells are able to change their firing patternsuddenly from one pattern to another. Thisphenomenonisknown as re-mapping. The placecells worktogether with other types of neuronsin the hippocampus and/or the surroundingregions of the brain to perform this kind ofspatial processing. Place cells are part of anon-sensory cortical system; their firingbehaviour is strongly correlated to sensoryinput. They adjust constantly and remap to suitthe current location and experience of thebrain. They do not work alone to create visuo-spatial representation but, on the other hand,

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are a part of a complex circuit that informsplace awareness and place memory.

It had been much debated as to whetherthe function of place cells is based uponlandmarks in the environment or onenvironmental boundaries or an interactionbetween the two. Several studies have beenmade in the past to find if hippocampalpyramidal cells of rats signal non-spatialinformation along with spatial information.There are simple place cells with purelylocational correlates as also complex placecells that increase their firing rate when theratencounters a particular object or experience.Others fire when a rat's expectations in aparticular location are not met or when theyencounter novelty along their path. The cellsthat fire in these situations are known asmisplace cells. Nowthere is abundant evidencedemonstrating the hippocampus to play a keyrole in spatial representation and spatialmemory in several mammalian species.

Grid Cells

Grid cells were discovered as projectionneurons in layers II and III of the medialentorhinal cortex in freely behaving rats. TheMosers became famous in 2005 with theirdiscovery of grid cells in the brains of rats.They showed that the firing pattern of the cellsremained constant even in the dark, and thatthey are independent of the animals' speed ordirection.Again, place cells in a rat brain maychange their fir ing ra tes when theirenvironment is slightly altered, e.g., by

changing the colour of the walls, while thoseof grid cells remain unchanged. The Mosersalso found that the different cells in theentorhinal cortex generate grids of manydifferent types, like overlapping honeycombs,big, small in relation to orientation andposition. They ultimately came to see that thebrain's grid cells are arranged according to aprecise mathematical rule.

These cells were subsequently found toexhibit sharply tuned spatial firing, much likeplace cells in the hippocampus, except thateach cell had multiple firing fields. The manyfields of each neuron formed a periodictriangular array, or grid, that tiled the entireenvironment explored by the animal. Thegraphics paper-like shape of the grid indicatedgrid cells as possible elements of a metricsystem for spatial navigation. Each grid ischaracterized by spacing (distance betweenfields), orientation (tilt relative to an externalreference axis), and phase (xy displacementrelativeto anexternal referencepoint).Althoughcells in the same part of the medial entorhinalcortex have similar grid spacing and gridorientation, the phase of the grid is non-topographic, i.e., the firing vertices ofcolocalized grid cells appear to be shiftedrandomly, just like the fields of neighbouringplace cells in the hippocampus. The spacingincreases monotonically from dorso-medial toventro-lateral locations, depending upon theincrease in size of place fields along the dorso-ventral axis of the hippocampus.According toHafting et al. (2005) cells in different parts of

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the enterorhinal cortex may have different gridorientations. The grid map is anchored togeometric boundaries and landmarks unique tothe environment. Thus the discovery of placecells and gride cells have "revolutionised ourunderstanding of how the brain knows wherewe are and is able to navigate within oursurroundings."

Recent studies have shown that similarsystems also exist in human brains .Understandinghow the brain mapsand navigatesspaces could prove to be critical for personssuffering fromAlzheimer's disease that affectsthe hippocampus and entorhinal cortex in thebrain, whereby many patients are disorientedand incapableof recognizingtheir surroundings.Understanding the brains inner GPS may helpus better investigate the mechanisms behindthe devastating loss of special memory thataffects people withAlzheimer's. This work hashelped to open new avenues for understandingother cognitive processes, such as memory,thinking and planning.

ReferencesHafting, T., Fyhn, M., Molden, S., Moser, M-B and Moser, E.I.(2005). Microstructure of a spatial map in the entorhinal cortex.Nature, 436:801-806.Lew, A. R. (2011). Looking beyond the boundaries: Time to putlandmarks back on the cognitive map. Psychological Bulletin,137 (3): 484-507.Moser, E.I., Kropff, E. And Moser, M-B. (2008). Place cells,grid cells and brains spatial representation system. Ann. RevNeuroscience, 31: 69-89.O'Keefe, J. and Dostrovsky, J. 1(971). The hippocampus as aspatial map. Preliminary evidence from unit activity in thefreely-moving rat. Brain Res., 34:171-175.O'Keefe, J. and Nadel, L. (1978). The Hippocampus as aCognitive Map. Oxford: Clarendon.

Flat No.401,BivabGulmoharApt., BeheraSahi, Nayapalli, Bhubaneswar

Email: nirajtripathy@rediffmail.com

3D PRINTING TECHNOLOGYMrs. Sushree Mishra

Introduction to 3D Printing

3D printing is a form of additivemanufacturing technology where a three

dimensional object is created by laying downsuccessive layers of material. It is also knownas rapid prototyping, is a mechanized method

whereby 3D objects are quickly made on areasonably sized machine connected to a

computer containingblueprints for the object.The3Dprintingconceptofcustommanufacturingis exci ting to nearly everyone. This

revolutionary method for creating 3D modelswith the use of inkjet technology saves time

and cost by eliminating the need to design;print and glue together separate model parts.

Typical 3D Printer

3D Printers are machines that produce

physical 3Dmodels fromdigital data by printinglayer by layer. It can make physical models ofobjects either designed with a CAD program

A typical 3D Printer

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immediately. The model tray then moves downthe distance of a layer and another layer of

power is deposited in position, in the model

tray. The print head again applies resin in the

shape of the model, binding it to the first layer.

This sequence occurs one layer at a time until

the model is complete. Very recently Engineers

at the University of Southampton in the UK

have designed, printed, and sent skyward the

world's first aircraft manufactured almost

entirely via 3-D printing technology.

Current 3D Printing Technologies

Stereo lithography - Stereo lithographic

3D printers (known as SLAs or stereolithography apparatus) position a

perforated platform just below the

surface of a vat of liquid photo curable

polymer. A UV laser beam then traces

the first slice of an object on the surface

of this liquid, causing a very thin layer of

photopolymer to harden.

Fused deposition modeling - Here a

hot thermoplastic is extruded from a

temperature-controlled print head to

produce fairly robust objects to a high

degree of accuracy.

Selective laser sintering (SLS) - Thisbuilds objects by using a laser to

selectively fuse together successive

layers of a cocktail of powdered wax,

ceramic, metal, nylon or one of a range

of other materials.

or scanned with a 3D Scanner. It is used in a

variety of industries including or jewelery,footwear, industrial design, architecture,

engineering and construction, automotive,aerospace, dental and medical industries,

education and consumer products.

History of 3d Printing

The technology for printing physical 3D

objects from digital data was first developedby Charles Hull in 1984. He named the

technique as Stereo lithography and obtained apatent for the technique in 1986.

While Stereo lithography systems hadbecome popular by the end of 1980s, othersimilar technologies such as Fused DepositionModeling (FDM) and Selective Laser Sintering(SLS) were introduced.

In 1993, Massachusetts Institute ofTechnology (MIT) patented another technology,named "3 Dimensional Printing techniques",which is similar to the inkjet technology usedin 2D Printers.

In 2005, Z Corp. launched a

breakthrough product, named Spectrum Z510,which was the first high definition color 3DPrinter in the market.

Manufacturing Modelwiththe 3DPrinter

The model to be manufactured is built upa layer at a time. A layer of powder isautomatically deposited in the model tray. Theprint head then applies resin in the shape of themodel. The layer dr ies solid almost

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Multi-jet modelling (MJM)- Thisagain builds up objects from successivelayers of powder, with an inkjet-like printhead used to spray on a binder solutionthat glues only the required granulestogether.

The VFlash printer, manufactured byCanon, is low-cost 3D printer. It's knownto build layers with a light-curable film.Unlike other printers, the VFlash buildsits parts from the top down.

Desktop Factory is a startup launched bythe Idealab incubator in Pasadena,California.

Fab@home, an experimental projectbasedat Cornell University, usesa syringeto deposit material in a manner similarto FDM. The inexpensive syringe makesit easy to experiment with differentmaterials from glues to cake frosting.

Th e Nanofact ory 3D printi ngtechnologies are introduced that arerelated to the nanotechnologies.

3D Printing Capabilities:

As anticipated, this modern technologyhas smoothed the path for numerous newpossibilities in various fields. The list belowdetails the advantages of 3D printing incertain fields.

1. Product formation is currently the mainuse of 3D printing technology. These machinesallow designers and engineers to test out ideas

for dimensional products cheaply before

commit ting to expensive tool ing and

manufacturing processes.

2. In Medical Field, Surgeons are using 3d

printing machines to print body parts forreference before complex surgeries. Other

machines are used to construct bone grafts forpatients who have suffered traumatic injuries.

Looking further in the future, research isunderway as scientists are working on creating

replacement organs.

3. Architects need to create mockups oftheir designs. 3D printing allows them tocomeup with these mockups in a short period oftime and with a higher degree ofaccuracy.

4. 3D printingallowsartists to create objectsthat would be incredibly difficult, costly, ortime intensive using traditional processes.

3D Saves Time and Cost

Creating complete models in a singleprocess using 3D printing has great benefits.This innovative technology has been proven tosave companies time, manpower and money.

Companies providing 3D printing solutionshave brought to life an efficient and competenttechnological product.

Sources

http://www.explainingthefuture.com/3dprinting.htmlhttp://en.wikipedia.org/wiki/3D_printinghttp://www.mahalo.com/3d-printers/http://net.educause.edu/ir/library/pdf/DEC0702.pdfhttp://www.inventioncity.com/intro-to-3-d-printing.html

Computer Science Department,

Rama Devi Women's (A) College, Bhubaneswar.

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Air Inside the House

Internal air in the house is more pollutedthan outside air. It is due to cooking, foodpreservation, CO

2due to energy waste, acidic

gas effects due to chemical process used forcleaning of floors and clothings, residues ofconstruction materials, old furniture's emittingdust and other harmful gases, air conditioningexhaust and other e-wastes, insecticides usedfor food preservation, radiationdue to T.V. andother domestic electronic gadgets. The insidepollution cannot freely spread outside due tolimitation of air transfer. So people spendingmore time inside the house particularlyhousewives are more affected and ailing dueto this inside pollution. It is more acute withpeople habituated to modern life style.

Health Problem

One can feel the problem created byinternal pollution of the house. Generally itfeels like common cold or any other virusinfected ailment. Its severity depends on thepower of resistance of every individual. Mostof the times it attacks as allergy. But if onedoes not care and continues to remain in thepolluted interior of the house for monthstogether, it results in asthma, hypersensitivity,senselessness and other irregularities ofbreathing. If one continues further in thispolluted atmosphere for some years, he mayget attack of breathing tunnel disease, heartailments, even cancer. Needless to say that itis always advisable to take steps for reducingpollution inside the house.

Means of Reducing Pollution Practice to reduce wastage of cooking

gas, other fuels and electricity used assource of energy in domestic sphere.

HEALTH SECURITY AGAINSTTHE INVISIBLE KILLER

Er. Ramesh Chandra Sahoo

Living organisms depend on food, waterand air for their health and survival. A humanbeing requires about 3 kgs of food, 5 kgs ofwater and 15 kgs of air on each day. Attemptsare always made to get good food and purifiedwater in the house for a healthy life. Everymodern habitat isequipped with developedfoodpreparation and storage system and portablewater purifiers. But no serious thought hasbeen made on availability of clean air insidethe house. This is mainly due to lack ofawareness. But clean air is more essential forgood health as its quantity is three to fivetimes more than the other two essentials. Assuch polluted air is an invisible killer for life.

What is Clean (Mountain) Air

Generally carbon dioxide (CO2), acidicgas and other green house gases present in theair, make it polluted. Along with it suspendeddust particles increase the pollution contentfurther. A survey conducted scientifically haspresented comparative air purification detailsin their findings.According to this, clean air isavailable in mountain ranges. As such it iscalled mountain air. This air is also available inareas like water falls and sea shores. Mountainair contains positive and negative ions of samequantity. Butair present near citieshasdifferentquantity of both the ions. Negative ions getmuch reduced as compared to positive ions.The ratio of these ions in the air, near severelypolluted cities and industrial areas is 4:1.Thisair is detrimental to health.

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QUIZ ON WATERBirat Raja Padhan

1. In Global water resources, the freshwater occupies .................(a) 2.8% (b) 2.3%(c) 2.9% (d) 2.2%

2. Theaverage rainfall in India is .................(a) 365cm (b) 114 cm(c) 120cm (d) 116cm

3. The rock which does not allow water topass through it is .................

(a) Porous rock (b) Non porous rock(c) Both of these (d) None of these

4. The concept of hydrologic cycle wascorrectly postulated for the first time ...............(a) Plato (b) Aristotle(c) Leonardo da vinci (d) Vittuvirus

5. Water can be .................(a) Solid (b) Liquid(c) Gas (d) All of these

6. Study concerned with applying thefindings of geologic research to earthenvironment is called .................(a) Earth Geology(b) Hydrology(c) Mining Geology(d) Environmental Geology

7. Study of water bodies while applying theknowledge of geology is called .................(a) Environmental Geology(b) Astrogeology(c) Hydrology(d) Economic Geology

Practice to work outside the house, i.e.open terrace or verandah or roof as muchtime as possible.

Use air-conditioners only at the time ofdirenecessity.Set thetemperatureControllerat the maximum comfortable position.

Keep small plants in pots inside therooms, specially in kitchen and take careof the pollutants.

Room Pollution Controller (RPC)

Science has developed room pollutioncontroller for air cleaning. In other countriesoutside Bharat it is being used in allair-conditioned houses and cars. Thisequipment uses electricity to generate onlynegative ions to supply it to internal atmosphere.It creates development in the ratio of positiveand negative ions of internal air. This is ameans to purify air and make it healthy.

It has also been seen by experiments thatthis equipment removes bad odor and foulsmell from the house. It's use is primarily tobring mental happiness inside the house. Itreduces chancesof pulmonarydiseases. Severalbrands of such equipment are now available inIndian markets. It suits the pocket of anygeneral consumer. Modern housewives shouldinstall such equipments inside their houses, inevery room if possible. It is more useful thanrefrigerator and aquaguard. It is the bestadvisable means to protect at tack ofINVISIBLE KILLER.

CLEAN AIR; HEALTHY AIR.

403 Saheed Nagar,Bhubaneswar, Mobile : 09438011072

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8. An instrument that measures the amount

of rainfall at a given time .................(a) Rain gauge (b) Anemometer(c) Current meter (d) Ammeter

9. The Study emphasizing hydrologic

aspects is .................(a) Cryology (b) Hydrogeology(c) Geo Hydrology (d) Potomology

10. The plants are disinfected by water byadding .................

(a) Iodine (b) Chlorine(c) Fluorine (d) None of these

11. The method used for desalting seawater .................

(a) Forward osmosis(b) Reverse osmosis(c) Electro osmosis(d) Osmosis

12. How much water does a person take in

his lifetime ...........................(a) 60,600 liter (b) 70,600 liter(c) 55,600 liter (d) 65,600 liter

13. The substances which are highly soluble

in water are .....................

(a) Salt and Sugar (b) Salt and glucose(c) Salt and Sulphur (d) Salt andChlorine

14. The common substance present inwater ..........................(a) Calcium salt

(b) Calcium bicarbonate(c) Both a & b(d) None

15. Acid rain causes ..............(a) Erosion of metals(b) Corrosion of metals(c) Both a & b(d) None

16. The average amount of water consumedby Indian per day ...............(a) 100 litre (b) 200 litre(c) 300 litre (d) 400 litre

17. Calcium poisoning in water leads to...............................(a) Itai Itai (b) Goitre(c) Cancer (d) Cretinism

15. Major sourceof ocean pollution ..............(a) Domestic wastage (b) Oil(c) Organic Matter (d) Chemicals

19. Safe water is the one which does notcontain .....................(a) Pathogenic bacteria (b) Turbidity(c) Any test (d) Any colour

20. pH value of water indicates its ............

(a) Acidiry (b) Alkalinity(c) Both a & b (d) None

ANSWERS

1. (a) 2. (b) 3. (b) 4. (d) 5. (d)

6. (d) 7. (c) 8. (a) 9. (c) 10. (c)

11. (b) 12. (a) 13. (a) 14. (c) 15. (b)16. (b) 17. (a) 18. (b) 19. (a) 20. (c)

At - Benkamura, P.O. - Pandari, Via - ITPS Banaharpali,Dist-Jharsuguda-768234

Mob - 9937271623,Email-padhanbiratraja@yahoo.com