WEIZM

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IntroducingNew Scientists2013-2014

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Introducing New Scientists 2013-2014

Table of contents

6 INTRODUCTION

Investinginthefutureofscience

8 DEPARTMENT OF COMPUTER SCIENCE AND APPLIED MATHEMATICS

Dr.ZvikaBrakerski Thefutureofinformationsecurity

10 DEPARTMENT OF PARTICLE PHYSICS AND ASTROPHYSICS

Dr.RanBudnik Searchingfordarkmatter

12 DEPARTMENT OF MATHEMATICS

Prof.TsachikGelander Geometryanddynamicsofgroups

14 DEPARTMENT OF CONDENSED MATTER PHYSICS

Dr.KarenMichaeli Phenomenaclosetoquantumcriticalpoints

16 DEPARTMENT OF NEUROBIOLOGY Dr.MichalRivlin Seeingdeepintotheretina

18 DEPARTMENT OF MOLECULAR GENETICS

Dr.Noam-SternGinossar Profilingviralinfections

20 DEPARTMENT OF MOLECULAR CELL BIOLOGY

Dr.RavidStraussman Understandingresistancetochemotherapy

22 DEPARTMENT OF CHEMICAL PHYSICS

Dr.AssafTal Improvingmagneticresonanceimaging

24 DEPARTMENT OF BIOLOGICAL REGULATION

Dr.IgorUlitsky DelvingintothemysteryoflincRNAs

26 DEPARTMENT OF NEUROBIOLOGY

Dr.YanivZiv Observingmemories

29 Newscientistfundsandgifts

6 7

INTRODUCTION

Investing in the future of science

This booklet will introduce you to 10 such

creative and talented young researchers

recruited in 2013.

Prof. Tsachik Gelander joined our

Department of Mathematics from

the faculty of Hebrew University of

Jerusalem. The rest are fresh from

postdoctoral fellowships in the U.S.

Five completed their PhDs here at the

Institute before going abroad for their

postdoctoral training.

It is commonly understood in the realm

of Israeli science that overseas training,

particularly in the postdoctoral period,

is vital to the continued advancement

and renewal of Israeli science. Therefore,

this year we are especially proud that

three beneficiaries of the Weizmann

Institute’s National Postdoctoral Award

Program for Women in Science, which

funds women scientists during their

postdoctoral years abroad, have accepted

offers by the Weizmann Institute to join

its faculty. They are: Dr. Michal Rivlin,

a graduate of the Hebrew University

Each year, the Weizmann Institute of Science searches leading research labs around the world for the most promising researchers who are rising stars in their fields. We seek out the young pioneers who are breaking into new areas of science and mathematics, no matter what their topic, because we believe that the best science is done by the best people.

and a postdoc at the University of

California at Berkeley, who is joining the

Department of Neurobiology; Dr. Karen

Michaeli, a Weizmann Institute graduate

who has been training at MIT, joins

the Department of Condensed Matter

Physics (our second woman tenure-track

scientist in that male stronghold). And

Dr. Noam Stern-Ginossar, a graduate of

the Hebrew University and a postdoc

at the University of California at San

Francisco, who is joining the Department

of Molecular Genetics.

In establishing their labs at the

Weizmann Institute and building their

respective teams of staff scientists,

postdocs, and students, these bright

young scientists serve as catalysts for

new ideas and directions and enrich the

existing investigations underway in our

laboratories. I invite you to read about

their work in these pages and share in

our excitement and anticipation as they

begin to establish themselves on campus.

Prof. Daniel Zajfman

President, Weizmann Institute of Science

8 9

The future of virtual information storage

and sharing is in the “cloud”— networks

of shared, remote servers to which users

can connect in order to view, deposit, or

retrieve information. How does one make

sure that only those designated can view

the information stored?

One way of keeping information

safe is to encrypt it, and the most

attractive encryption form of all is fully

homomorphic encryption (FHE). This yet-

to-be-fully-realized encryption scheme is

the holy grail of cryptography. It could be

DEPARTMENT OF COMPUTER SCIENCE AND APPLIED MATHEMATICS

The future of information security

As the use of cloud computing has become more and more widespread, the most pressing issues become those of security and privacy.

used, for example, to make stored data

invisible to the remote host server while

still available for usage by the owners of

the information. This will enable entities

to outsource computation functions to a

third party while keeping the information

itself private.

Thirty years of intensive research

worldwide preceded the great FHE

breakthrough of 2009, when an IBM

research team led by Craig Gentry

delivered the first plausible, yet too

unwieldy, candidate FHE scheme.

Dr. Zvika Brakerski Dr. Zvika Brakerski completed his BSc summa cum laude in electrical

engineering and computer science in 2001 and his MSc summa cum

laude in electrical engineering systems in 2002, both at Tel Aviv

University. After receiving his PhD in computer science and applied

mathematics from the Weizmann Institute in 2011, he went on to

conduct postdoctoral research at Stanford University. He joined the

Weizmann Institute faculty in 2013.

Dr. Brakerski’s academic and professional honors include the Tel Aviv

University Rector Award in 1998 and 1999, the Check Point Award and

Scholarship in 2000, the Knesset (Israeli Parliament) Award in 2000,

the Wolf Foundation Scholarship in 2001, the Intel Israel Award for MSc

students in 2002, the Check Point Institute for Information Security

Award in 2011, and the Simons Postdoctoral Fellowship in 2011.

Fully Homomorphic Encryption

(FHE) allows “blindfolded

computation” where the server is

oblivious to the input and output

of the computation.

Dr. Zvika Brakerski, together with

colleagues, took the next major research

step forward. He was able to put FHE

on solid theoretical ground and provide

the means to achieve significantly more

efficient schemes, bringing FHE closer

to real-life applications. Moreover, Dr.

Brakerski’s FHE algorithms form the basis

for all modern implementations of FHE.

Dr. Brakerski’s main research goal

for the coming years is to make FHE

as easy to use and understand as the

RSA algorithm, the most widely used

algorithm for securing Internet, banking,

and credit card transactions. In parallel,

Dr. Brakerski will continue his ongoing

research on other cryptography issues,

such as leakage-resilient encryption and

circular security problems, as well as hot

topics like interactive information theory

and interactive coding problems.

10 11

Dark matter is one of the most striking

unsolved mysteries in physics today.

Scientists have yet to detect it directly,

but almost all measurements of the

motion of galaxies, the evolution of the

universe, and the behavior of matter in

the known universe have led scientists to

believe that there must be a tremendous

amount of mass in the universe that is not

made of conventional matter.

One of the leading theories about the

nature of dark matter is that it consists

of weakly interacting massive particles

(dubbed WIMPs) that contain far more

mass than protons and neutrons, but that

rarely interact with conventional matter.

They give off no light or electromagnetic

radiation, but are affected by gravity.

Scientists believe that a promising way to

detect WIMPs is by looking for evidence

of them colliding with the nuclei of visible

matter. This is where Dr. Budnik joins the

search. He worked on radiation detectors

during his postdoctoral research at the

Weizmann Institute, and for the past three

years he has analyzed data taken by the

Xenon100 experiment.

surface, where they are accelerated and

emit a second pulse of photons.

Dr. Budnik is helping to design and

build the cryogenic systems for the future

detector Xenon1T that will keep the

instruments cool and working at the low

temperatures needed for the liquefaction

and maintenance of 3.5 tons of liquid

xenon. This experiment will be submerged

by a water bath containing instruments

being designed at the Weizmann Institute.

The detector is expected to be about

100 times more sensitive than the

current Zenon100 system. Dr. Budnik is

the lead scientist on a test project, the

Xenon1T demonstrator, that is a full-scale

prototype of the new 1-ton system that

must prove the possibility of measuring

the ionization signal of electrons

“drifting” up to a meter from the site of

the collision to the surface of the xenon.

Only after the demonstrator succeeds

in its mission could scientists give the

green light to building the next generation

Xenon1T system.

Dr. Budnik aims to be an integral

part of the worldwide scientific efforts

to discover evidence of dark matter

through the conclusion of the Zenon100

project, building and operating the next-

generation Xenon1T, and the planned

DARWIN international project to build

multi-ton scale liquid xenon and argon

detectors. He will combine small-scale,

proof-of-concept experiments built at the

Weizmann Institute in cooperation with

the large international coalitions.

DEPARTMENT OF PARTICLE PHYSICS AND ASTROPHYSICS

Searching for dark matter

Dr. Ran Budnik is part of an international team of scientists creating new instruments they hope will show the first confirmed interactions between so-called “dark matter” and “normal,” baryonic, matter.

To be able to isolate the experiment

from almost all other possible

interactions, the Xenon100 international

research team works deep underground

at the Gran Sasso National Laboratory

(LNGS), built next to a highway tunnel

under a mountain near Rome. They are

using a super-cooled vat of 100 kilograms

of liquid xenon surrounded by an array

of photon detectors, inside an electric

field cage that allows a 3D reconstruction

of each interaction. Collisions between

WIMPs and the nuclei of conventional

matter are expected to be very rare

events, given the extremely weak

interaction strength. However, liquid

xenon has several properties that make it

a promising medium for detecting these

collisions: It is free of impurities, has no

long-lived radioactive isotopes, and emits

two simultaneous signals following a

collision: a photon of light and a charged

electron. Dr. Budnik tackles the difficult

task of trying to match the detection

of the photons by the array of photon

detectors, with the signature of a charge

of electrons reaching the liquid xenon

Dr. Ran BudnikDr. Ran Budnik completed his BSc in physics and

mathematics in the elite Israel Defense Forces Talpiot

training program at the Hebrew University of Jerusalem

in 1997. From 1994 to 2004 he served as a cadet and

then as a research scientist in the IDF. He was awarded

his MSc at the Technion—Israel Institute of Technology in

2004, and his PhD in physics at the Weizmann Institute

in 2009. He spent the next year as a postdoctoral fellow

at the Weizmann Institute. From 2010 until joining the

Weizmann Institute in 2013, he was a postdoctoral fellow

scientist at Columbia University working on the XENON

dark matter project.

Dr. Budnik won first place in the Israel Physics

Olympics in 1994 and went on to win a silver medal in

theoretical physics at the International Physics Olympics

that year. He was on the Dean’s List at Hebrew University

in 1995. Dr. Budnik was commander of the third-year

students in the IDF Talpiot program in (2000–2001), and

completed his service at the rank of major.

12 13

Together with Prof. Itai Benjamini from

the Department of Mathematics, Prof.

Gelander has explored these questions,

which involve approximating the most

perfectly round ball that can exist by

using a branch in mathematics known as

Group Theory.

At the Weizmann Institute, Prof.

Gelander plans to deepen his research in

Group Theory, which involves the study

of algebraic structures known as groups

and which has many applications in both

physics and chemistry. He will also branch

out into other areas of mathematics.

One of his most recent achievements

has involved using Group Theory to

play a role in solving one of the more

baffling theorems that has eluded

mathematicians for over 50 years,

known as the “L_1 fixed point” theorem,

DEPARTMENT OF MATHEMATICS

Geometry and dynamics of groups

How round can a soccer ball be? What makes a perfect sphere? It is questions just like these with which mathematicians such as Prof. Tsachik Gelander are fascinated.

which implies the best solution to a

well-known derivation problem. If one

takes a map of the world and puts it

down anywhere, there will always be a

point on the map that sits exactly on

the actual physical place it represents.

Most people would take it for granted,

but not mathematicians. To solve it, Prof.

Gelander and other mathematicians

took a fresh approach to the problem.

To prove their solution, they needed to

find a fixed point for every possible case.

Since the number of possible maps is

infinite, they were looking for a universal,

purely mathematical method, one that

would work in any situation – and they

succeeded. Prof. Gelander and his team

found a simple one-page solution to this

theorem that opens up new perspectives

in physics and economics.

Prof. Tsachik GelanderProf. Tsachik Gelander completed his BA and MSc in mathematics (1995

and 1998) at the Technion—Israel Institute of Technology. He earned his

PhD in mathematics in 2004 from the Hebrew University of Jerusalem.

Between 2003 and 2006 he was a Gibbs Assistant Professor at Yale

University. He later returned to be a senior lecturer at the Hebrew

University, and from 2008–2013 worked as an Associate Professor

there. He joined the faculty at the Weizmann Institute in 2013.

His honors include the Clore Scholarship (2001), the Marie Curie

Fellowship (2002), the Giora Yashinski Prize for PhD students (2002),

the Schlomiuk Prize for PhD thesis (2004), an NSF grant (2005),

the Nessyahu Prize of the Israel Mathematical Union (2006), an

ISF grant (2007), and an ECR grant (2008). Prof. Gelander has also

helped in guiding and teaching the Israeli team for the International

Mathematical Olympiad (IMO).

14 15

The interactions between electrons

can make them lose their individual

identities and act collectively to realize

new states ranging from insulators

to superconductors. Dr. Michaeli is

interested in these novel phases and

the signatures of their unconventional

collective behavior. Her research at the

Weizmann Institute will focus on quantum

transport phenomena in interacting

systems; thermoelectric phenomena

close to quantum critical points; vortex

dynamics; new electronic phases at oxide

interface structures; unconventional

superconductivity; localization-

delocalization effects and quantum

dissipation; and spin-orbit coupling.

One such interesting thermoelectric

phenomenon is the strong transverse

thermoelectric current, called the Nernst

DEPARTMENT OF CONDENSED MATTER PHYSICS

Phenomena close to quantum critical points

Quantum condensed matter physics fascinates theoretical physicists like Dr. Karen Michaeli because of the variety of phases arising from simple ingredients, electrons, and ions in a solid.

Dr. Karen MichaeliDr. Karen Michaeli graduated summa cum laude in physics and

magna cum laude in computer science at Tel Aviv University

in 2003. She completed an MSc (2006) and a PhD (2010)

in condensed matter physics at the Weizmann Institute of

Science with Prof. Alexander Finkelstein. Dr. Michaeli studied

condensed matter theory as a Pappalardo postdoctoral fellow

in the Department of Physics at the Massachusetts Institute

of Technology from 2010 until joining the Department of

Condensed Matter Physics as a Senior Scientist in 2013.

Dr. Michaeli won a fellowship in 2010 from the National

Postdoctoral Program for Advancing Women in Science

established by the Weizmann Institute in addition to her

Pappalardo Postdoctoral Fellowship at the Department of

Physics at the MIT from 2010 to 2013. She was awarded the

Elchanan E. Bondi Memorial Prize in 2010, the Wolf Foundation

scholarship for PhD students in 2009, and the Dean’s Prize for

MSc students in 2006, all at the Weizmann Institute.

Schematic plot of the LaAlO3 and SrTiO

3

interface structure showing the composition

of each layer and the ionic charge state

of each layer that is part of Dr. Michaeli’s

theoretical model.

effect, measured in films near the

superconducting phase transition. As a

part of her PhD thesis, Dr. Michaeli

developed a theoretical model that

showed how this strong Nernst effect

signal could be used to analyze

thermal and thermoelectric transport

using the quantum kinetic equation.

Her approach might help illuminate

the nature of skyrmions, which are

quasi-particles that are collective

excitations in unconventional magnets

and superconductors. Substantial

experimental efforts have been dedicated

to detecting skyrmions. Despite

considerable progress, measuring their

configurations in many systems remains

challenging. She predicts that using the

Nernst effect might allow physicists to

distinguish between skyrmions, which

should demonstrate this strong magnetic

signal, and vortices, which have a much

weaker signature.

Recently, she constructed a model

explaining other unexpected quantum

phenomena found at oxide interface

structures. Scientists observed that both

superconductivity and ferromagnetism

could co-exist at the interface between

lanthanum aluminate (LaAlO3) and

strontium titanate (SrTiO3). Her

model was able to explain the origin

of the ferromagnetism in this unique

interface and show how its coexistence

with superconductivity was made

possible by an unconventional pairing

between electrons supported by spin-

orbit coupling. She plans to explore

the effects of such interactions on

electron localization and the interplay of

superconductivity and spin-orbit coupling,

as well as entanglement.

16 17

The retina has special neurons that

are light-sensitive; they transduce light

signals into electrical signals that travel

along the retinal neurons and from there

to the other parts of the brain. As a

neurobiologist, Dr. Michal Rivlin is trying

to understand how the retina encodes the

visual scene and how it communicates

with the brain. The retina has a simple

layered structure and yet it performs

complex computations on the visual field.

Therefore, the retina is a unique window

into the central nervous system.

Dr. Rivlin studies a unique type of cell

in the retina, called direction-selective

retinal ganglion cells, that encode motion.

These cells respond to motion in one

“preferred” direction, but do not respond

to motion in the opposite direction.

However, in a recent paper published in

the journal Neuron, she demonstrated

that short, repetitive stimulation with

a moving pattern can cause direction-

selective cells to reverse their directional

preference.

This insight about the adaptive

ability of neuronal circuits in the retina

is entirely new; the fact that they can

actually change their function in response

to sensory input is a paradigm shift in

understanding how the retina functions.

DEPARTMENT OF NEUROBIOLOGY

Seeing deep into the retina

Dr. Michal Rivlin is investigating the retina, and her research may have implications for reversing blindness in patients with retinal degeneration

In her new lab at the Weizmann Institute,

Dr. Rivlin plans to use repetitive

stimulation to explore the information

flow along the visual pathway and the

unique computational role of each

structure in the pathway. High-order

visual structures, such as the visual

cortex, are known to adapt and change

their visual responses following repetitive

stimulation.

Dr. Rivlin’s findings suggest the

adapted properties along the visual

pathway are not local but rather inherited

from the retina. Her research may lead

to new insights about the neurological

relationship between the eye and the

brain. It is also likely to have implications

for restoring vision in patients blinded by

retinal degeneration, such as inherited

retinitis pigmentosa or age-related

macular degeneration.

Dr. Michal RivlinDr. Michal Rivlin graduated magna cum laude with a BS in mathematics

and computer science from the Hebrew University of Jerusalem

in 2001. She completed her PhD in the Interdisciplinary Center for

Neural Computation at the Hebrew University in 2009. Dr. Rivlin was a

postdoctoral fellow in the Department of Molecular and Cell Biology

and the Helen Wills Neuroscience Institute at the University of California

at Berkeley from 2009 until joining the faculty of the Department of

Neurobiology at the Weizmann Institute in 2013.

Dr. Rivlin won a Revson Award in 2009 from the National

Postdoctoral Program for Advancing Women in Science established by

the Weizmann Institute. She won a Human Frontier Science Program

Long-Term Fellowship in 2010, and an Edmond and Lily Safra Fellowship

in Brain Science in 2009. Her honors also include: Dean’s Awards for

outstanding achievement and a Rector’s PhD scholarship for excellence

from Hebrew University, a Katzir student travel fellowship, the Nitza

Ilan prize for outstanding students in electrophysiology, and a National

Institute for Psychobiology in Israel travel award.

Four neighboring direction-selective retinal ganglion

cells that were filled with fluorescent dye. All cells

are tuned towards the same direction (posterior

direction). Bottom: A rotation of the image

demonstrates that the cells send their processes to

collect input from two distinct layers; the ON and

OFF layers provide the input on motion of objects

that are brighter and darker than the background,

respectively.

18 19

Viruses are completely reliant on the

host cell’s machinery and have evolved

various mechanisms to hijack it for their

propagation. At the same time, host cells

have developed defense mechanisms to

cope with viral infections.

Dr. Noam Stern-Ginossar employs

a cutting-edge sequencing technique

termed “ribosome profiling” to reveal

a comprehensive view of the act of

translation, the end products of which

are proteins. The robustness, scale, and

accuracy of this method radically increase

her ability to monitor the synthesis of

new proteins and provide Dr. Stern-

Ginossar a unique opportunity to follow

the molecular events underlying infection

with unprecedented depth.

DEPARTMENT OF MOLECULAR GENETICS

Profiling viral infections

Dr. Noam Stern-Ginossar’s research aims to reveal the complex cellular changes occurring during virus-host cell encounters.

Dr. Stern-Ginossar’s main viral model is

the human cytomegalovirus (HCMV). This

virus infects the majority of humanity, and

can lead to severe disease in newborns and

immunocompromised adults, such as organ

transplant recipients, patients undergoing

hemodialysis, patients with cancer, those

receiving immunosuppressive drugs, and

HIV-infected patients.

In her PhD studies, Dr. Stern-Ginossar

revealed a novel method by which HCMV

evades recognition by the host’s immune

system—an achievement hailed by Nature

Medicine as one of the notable scientific

advances of 2007.

In addition to delineating the protein

composition of HCMV-infected host cells at

various stages of infection, she discovered

in her postdoctoral work 641 new HCMV

regulatory genomic regions, thereby

opening the way to understanding the

functions of hundreds of novel viral genes.

In her new lab at the Weizmann Institute,

she intends to further her study of the

mode of operation of key HCMV regulatory

factors and proteins and host infection,

evasion, and propagation mechanisms. She

will also extend her research to the study

of the Influenza A virus, the only influenza

variant known to have been responsible for

pandemics.

Dr. Noam Stern-GinossarDr. Noam Stern-Ginossar earned her BSc in 2002, her MSc in 2005, and her

PhD in immunology with distinction in 2009, all from the Hebrew University of

Jerusalem. She studied as a postdoctoral scholar at the University of California,

San Francisco, starting in 2010. She joins the Weizmann Institute in January 2014.

Dr. Stern-Ginossar has been awarded a number of academic and professional

honors, including the Wolf Prize for MSc Students in 2005, the Adams Fellowship

for PhD Students in 2006, the Wolf Prize for PhD Students in 2007, the Chorafas

Prize for Excellence in Scientific Research in 2007, the James Sivartsen Award

for Excellence in Cancer Research in 2009, an EMBO Long-Term Postdoctoral

Fellowship in 2010, the Weizmann Institute of Science National Postdoctoral

Award Program for Advancing Women in Science in 2010, the Human Frontiers

Postdoctoral Fellowship in 2011, and the Clore Prize in 2013.

HCMV-infected cells harvested at different times

after infection for ribosome footprint analysis.

20 21

In many forms of cancer, including the

skin cancer known as melanoma, tailored

drugs can eradicate cancer cells in

the lab, but often produce only partial,

temporary responses in patients. One

of the burning questions in the field of

cancer research has been and remains:

How does cancer evade drug treatment?

Dr. Ravid Straussman made a

surprising discovery about cancer drug

resistance during his postdoctoral

research. He showed evidence that

normal cells that reside within the tumor,

part of the tumor microenvironment,

may supply factors that help cancer

cells grow and survive anti-cancer

drugs. He developed a high-throughput

screening and co-culture system to test

the ability of 23 normal, stromal cell

types to influence the innate resistance

of 45 cancer cell lines to 35 different

anticancer drugs. He found that the

presence of normal cells helped cancer

cells survive more than half the drugs—

while the cancer cells cultured alone

without any normal cells generally died.

DEPARTMENT OF MOLECULAR CELL BIOLOGY

Resistance to chemotherapy in advanced cancer patients is almost always the rule rather than the exception despite a transformative change in our understanding of cancer biology and a surge in novel anticancer drugs.

Exploring further to find the possible

factors involved, he studied the fast-

growing and often deadly cancer

melanoma. His research suggested that

hepatocyte growth factor (HGF) derived

from stromal cells can contribute to the

resistance of melanoma cells to cancer

drugs designed to inhibit an oncogene

known as BRAF. The effects of normal

cells in the tumor microenvironment

on innate resistance of cancer cells

represent an as-yet largely underexplored

area. In his new lab at the Weizmann

Institute, Dr. Straussman plans to

explore the basic biology that underlies

various kinds of innate drug resistance.

For instance, he notes the presence of

bacteria as well as the normal cells in

solid tumors and is curious about what

effect they might also have on chemo-

resistance. He is also intrigued with the

extraordinarily adaptive ability of cancer

cells to use alternative signaling pathways

in response to therapy and how they can

acquire resistance through genetic and

epigenetic changes.

Dr. Ravid StraussmanDr. Ravid Straussman was born in Israel. After service in the Israel Air Force,

he completed a BSc summa cum laude at the Hebrew University Hadassah

Medical School in 1997. He earned his MSc in medical biochemistry there

in 1998 and entered the MD/PhD program. He served his MD internship at

Rabin Medical Center in Petah Tikva (2002–2003), and completed his PhD in

the Department of Medical Biochemistry at the Hebrew University in 2005.

Dr. Straussman was a postdoctoral fellow in the Department of Cellular

Biochemistry and Human Genetics at Hebrew University from 2005 to 2008.

He worked as a postdoctoral fellow at the Broad Institute of Harvard and MIT

from 2008 until joining the Weizmann Institute in 2013.

His prizes and honors include the Dean’s and Rector’s prizes plus an award

for excellence in research at the Hebrew University Hadassah Medical School;

a Foulkes Foundation fellowship, a Philip Morris Postdoctoral Fellowship, and

an American Association for Cancer Research (AACR) Scholar-in-Training

Award in 2012.

Understanding resistance to chemotherapy

22 23

Magnetic Resonance Spectroscopy (MRS)

and Imaging (MRI) are non-invasive

tools scientists use to study metabolism,

biochemistry, and physiology in living

organisms. With recent improvements

in these fields, scientists can now view

metabolic pathways in action such as the

phosphocreatine-ATP energy cycle, or

the concentrations of metabolites in

the brain.

During his PhD studies at the

Weizmann Institute, Dr. Tal worked with

Prof. Lucio Frydman of the Department of

Chemical Physics, a pioneer in the field of

magnetic resonance, and the inventor of

spatially encoded single-scan MRI. Prof.

DEPARTMENT OF CHEMICAL PHYSICS

Improving magnetic resonance imagingDr. Assaf Tal has chosen to concentrate on the fascinating intersection between biology and the chemical physics that has helped drive the ongoing revolution in MRI.

Frydman was able to speed up the MRI

process considerably by using physics,

mathematics, and computer analysis

to squeeze more information out of a

single scan, eliminating time-consuming

multiple scans wherever possible. For

instance, by tailoring the characteristics

of their scanning pulses, Dr. Tal and

Prof. Frydman noted that they could get

information about interactions between

the spin of molecules in the strong

magnetic field affected by the scan,

even when those fields were severely

distorted due to hardware imperfections

or metal implants. Unlike conventional

MRI processing, which requires multiple

scans, spatially encoded imaging requires

only one scan to produce a full two- or

three-dimensional image. Their innovative

approach has been recently successfully

demonstrated in human patients.

Armed with his experience at the

cutting edge of Nuclear Magnetic

Resonance (NMR) development, Dr. Tal

began to work on medical research

Dr. Assaf TalDr. Assaf Tal completed his BSc cum laude at the Hebrew

University in Jerusalem in 2001. He was awarded his MSc in

physics in 2004 and his PhD in physics in 2009, both at the

Weizmann Institute of Science. Dr. Tal has served as a post-

doctoral fellow at the New York University (NYU) Langone

School of Medicine starting in 2010. He joins the Department of

Chemical Physics at the Weizmann Institute in January 2014.

His academic and professional honors include an Amos

de-Shalit Scholarship in physics in 2002, a Wolf Award for

undergraduate students in 2003, a Clore Israel Foundation

Scholarship for Excellence in PhD Research from 2006 to

2009, and a Human Frontier Science Foundation Cross-

Disciplinary Fellowship for 2010-2012. He is a reviewer for

the Journal of Magnetic Resonance, Magnetic Resonance

in Medicine, and Magnetic Resonance Materials in Physics,

Biology and Medicine. Dr. Tal is a member of the International

Society for Magnetic Resonance in Medicine (ISMRM). He was

voted as an outstanding lecturer by students in an MRI Primer

course in 2010 and chosen as an outstanding teaching assistant

by students attending an NMR graduate course in 2008.

problems as a postdoctoral fellow at New

York University’s School of Medicine. He

tackled a number of challenges, such as

discriminating between “white matter”

and “grey matter” in brain scans. He

developed new pulse sequences and

methods for MRS of the human brain,

comparing healthy volunteers to patients

with multiple sclerosis. Conventional MRI

is sensitive to gray and white matter

atrophy and can distinguish active from

chronic lesions in multiple sclerosis,

but it cannot give a clear picture of

gliosis, inflammation, demyelination, and

neuronal loss.

With radiologists at NYU, Dr. Tal tested

new methods of NMR spectroscopy to

pick up some of this vital information for

studying the effects of multiple sclerosis.

He also helped develop NMR techniques

to study metabolic abnormalities in

patients with schizophrenia, as well as

to look at the damage to neuronal axons

following mildly traumatic brain injuries.

In his new lab at the Weizmann

Institute, Dr. Tal plans to use his unique

multidisciplinary blend of basic and

applicative scientific training to continue

working to improve MRI and MRS. His

proposed projects range from designing

new pulse sequences and creating new

algorithms for post-processing the

imaging data, to understanding how basic

chemical and physical phenomena give

rise to the contrasts seen in NMR images

and how these can be used to improve the

diagnosis, understanding and treatment

of disease.

24 25

Most known biological functions are

carried out by proteins, but DNA

sequences encoding them account for

less than two percent of the human

genome. Long stretches of DNA located

between the protein-coding genes

were typically assumed to have limited

function, and referred to as junk DNA.

However, recent studies have found

that these intergenic regions are not

inert, but rather persistently transcribed

into different classes of RNA molecules

including long intervening non-coding

RNAs, or lincRNAs. Their levels vary

DEPARTMENT OF BIOLOGICAL REGULATION

greatly across tissues, and variations

in the expression of lincRNAs have

been associated with a number of

human diseases, including cancer.

Several lines of evidence suggest that

many of the lincRNAs are functionally

important, and that their modes of

action differ fundamentally from those

of more established classes of genes.

However, functions remain unknown for

the vast majority of lincRNAs, and how

these functions are encoded in lincRNA

sequences remains poorly understood.

This is precisely the mystery that Dr.

Igor Ulitsky is working to solve.

After receiving a PhD in computational

biology from Tel Aviv University,

Dr. Ulitsky continued his postdoctoral

Dr. Igor UlitskyDr. Igor Ulitsky was born in St. Petersburg, Russia,

and earned a BSc in computer science and life

sciences in 2004 and a PhD in computational

science in 2009, both at Tel Aviv University. He

studied as a postdoctoral scholar at Whitehead

Institute for Biomedical Research in Cambridge,

Massachusetts, starting in 2009, and joined the

Weizmann Institute’s Department of Biological

Regulation in 2013.

Dr. Ulitsky has been awarded a number of

academic honors, including the President and

Rector’s MSc Fellowship (2004–2005), the Wolf

Prize for Outstanding PhD Students (2008),

the Legacy Heritage Fund Stem Cells Research

Fellowship (2009), and an EMBO Long-Term

Fellowship for postdoctoral research (2010–2011).

Blocking of two lincRNAs

affects morphogenesis and

neurogenesis during zebrafish

embryonic development.

Delving into the mystery of lincRNAs

Taking an interdisciplinary approach that combines experimental and computational tools, Dr. Igor Ulitsky’s goal is to understand the biology of lincRNAs and address challenges instrumental for their future diagnostic or therapeutic uses.

research at the Whitehead Institute

where he began his journey into the

world of RNA biology. Dr. Ulitsky studied

the functions and expression patterns

of lincRNA genes during the embryonic

development of zebrafish. This study was

the first large-scale mapping of lincRNAs

in a non-mammalian vertebrate, and the

first to identify lincRNAs that are required

for proper embryonic development.

At the Weizmann Institute, Dr.

Ulitsky will continue his work to

elucidate the enigmatic language of

the sequences of lincRNA genes and

the ways they specify lincRNA modes

of action. He hopes to shed light on

the syntax and the semantics of this

language, which will be essential for

uncovering the mechanisms used by

lincRNAs, as well as to understanding

their function in health and disease.

26 27

Memories persist in our brains for long

periods of time, some over the course of

a lifetime. Memories also change with

time: While at first they are sharp, with

time they can decay and become vague.

What happens to all this information in

our memory over our lifetimes? How

do different experiences or diseases

change it?

Neuroscientists think that memory

information is encoded in the group

activity of ensembles of neurons

in specific brain circuits. Each such

ensemble codes for a piece of

information, an element of memory. Until

now, it has been technically impossible

to track the activity of such neuronal

ensembles over long periods of time

(i.e., beyond a few days). Therefore,

despite the fact that memory is one of

the most investigated faculties of the

brain, neuroscientists today have a

poor understanding of memory’s most

DEPARTMENT OF NEUROBIOLOGY

Observing memoriesDr. Yaniv Ziv is addressing fundamental questions about memory that until now have been beyond scientists’ reach. Unlike traditional methods, which use wire electrodes to record electrical activity, Dr. Ziv’s experimental approach relies on optical imaging.

essential feature: the dynamic persistence

of information in the brain.

In his postdoctoral research at

Stanford University, Dr. Yaniv Ziv

developed a new experimental method

to observe thousands of neurons in the

brains of live mice over the course of

months. His system uses a number of

recent technical advances: a miniaturized

fluorescence microscope that researchers

can mount on the head of a freely-moving

mouse like a helmet; ultra-thin, rod-

shaped implantable lenses, which serve

as micro-endoscopes; and genetically

engineered indicators of neuronal activity

that “light up” when the neuron is fired.

The combination of these technologies

into one system produces high-resolution

imaging of cells deep within a living brain,

with the ability to embed these systems

for months.

Dr. Ziv implanted the high-tech neuron

monitoring devices in the hippocampus of

mice and tracked them as they navigated

simple mazes. In the hippocampus, so-

called “place cells”—neurons that fire

when the animal occupies a specific

location in the environment—have long

been recognized as important for memory

of places and events. When the devices

were turned on, Dr. Ziv was delighted

to see a “volcano” of activity, with

thousands of activated cells lighting up

in complex patterns. Each day, as the

mouse explored the maze, the pattern of

neurons firing involved a unique subset

of neurons, but his analysis showed that

Dr. Yaniv ZivDr. Yaniv Ziv earned a BSc in biology at the Hebrew

University of Jerusalem in 2001 and completed

the Direct PhD Program in neurobiology at

the Weizmann Institute in 2007. Dr. Ziv was a

postdoctoral fellow at the Department of Biology

at Stanford University starting in 2008. He joined

the Department of Neurobiology at the Weizmann

Institute in 2013.

Dr. Ziv’s academic and professional honors

include a number of student travel awards from

2004 through 2006, including the Katzir-Katchalsky

Student Travel Fellowship. He won the 2007 Otto

Schwartz Foundation award for excellence in

studies and research, and the Weizmann Institute

of Science award for an outstanding PhD thesis in

2007. Dr. Ziv was awarded a Rothschild Foundation

postdoctoral fellowship and a Machiah Foundation

postdoctoral fellowship. Since 2012, he has been

a scientific advisor for Inscopix in Palo Alto,

California, a biotech startup company based on an

innovative neural imaging technology.

about 20 percent of the cells overlapped

between any two of these subsets.

These cells appeared to retain the same

coding properties, which enabled Dr. Ziv

to predict where the mouse was in the

maze based on which set of neurons were

active. He now had a real-time view of

neurons forming and updating spatial

memories.

Dr. Ziv has a longstanding interest in

stem cells and is intrigued by the idea

that stem cells could be harnessed for

brain maintenance and repair. In his PhD

research with Prof. Michal Schwartz of

the Department of Neurobiology at the

Weizmann Institute, Dr. Ziv helped carry

out some of her paradigm-changing

research that showed how the immune

system is intimately involved with the

brain. Conventional wisdom at the time

held that the brain was isolated by the

blood-brain-barrier and not affected by

immune reactions. Dr. Ziv investigated

how the immune system triggers stem

cells to produce new nerve cells in adults,

a process called neurogenesis. This line

of research demonstrated that immune

cells contribute to maintaining life-long

hippocampal neurogenesis.

Dr. Ziv is curious about whether adult

neurogenesis also plays a part in memory

processing. He hopes to use the imaging

system to track the development and

activity of newly created neurons in

the hippocampus; and to explore the

biological basis of Alzheimer’s disease.

He predicts that there will be substantial

differences between transgenic

Alzheimer’s model mice and age-matched

controls in how place cells are coded.

He thinks that these differences may

be detectable weeks to months before

decline in memory and cognition can be

detected at the behavioral level. Such

differences could serve as biomarkers

for early diagnosis and the design of new

therapeutic interventions.

29

New scientist funds and gifts

TheWeizmannInstituteofSciencehasreceivedsubstantialgiftsforthebenefitofnewscientistsfromthefollowingindividuals,familiesandfunds,andwishestoexpressitsappreciationtothem:

Abisch-Frenkel Foundation for the Promotion of Life Sciences•

Abramson Family Center for Young Scientists•

Adelis Foundation•

Cynthia Adelson and Friends•

Ruth and Herman Albert Scholars Program•

Asher and Jeannette Alhadeff Research Award•

AMN Foundation for Science, Culture and Arts in Israel•

Candice Appleton Family Trust•

Azrieli Foundation•

Gerhard and Hannah Bacharach Charitable Trust•

Estate of David Arthur Barton•

Joseph Piko Baruch•

De Benedetti Foundation-Cherasco 1547•

Andrew and Froma Benerofe New Scientist Fund•

Leo M. Bernstein Family Foundation•

Estate of Shlomo (Stanislav) and Sabine Bierzwinsky•

Jonathan and Joan Birnbach•

Edith C. Blum Foundation•

Anne-Marie Boucher•

Frances Brody Young Scientists Fund•

Mr. and Mrs. Raymond Burton, CBE•

Carolito Stiftung•

Chais Family Fellows Program for New Scientists•

Sir Charles Clore Research Prize•

Clore Israel Foundation•

Lester Crown Brain Research Fund•

Estate of Ernst and Anni Deutsch•

Sir Harry S. Djanogly, CBE•

Rena Dweck New Scientist Endowment Fund•

Mel and Joyce Eisenberg Keefer Professional Chair for New Scientists•

Enoch Foundation•

Iby and Aladar Fleischman Foundation•

Judith and Martin Freedman Career Development Chair•

Meir and Jeanette Friedman Research Fellowship•

Estelle Funk Foundation President’s Fund for Biomedical Research•

Fusfeld Research Fund•

Paul and Tina Gardner•

Alice Schwartz Gardos New Scientist Fund•

30 31

Estate of Dorothy Geller•

Gephen Trust•

Estate of Jack Gitlitz•

Ilan Gluzman•

Peter and Patricia Gruber Awards•

Gurwin Family Fund for Scientific Research•

Leona M. and Harry B. Helmsley Charitable Trust•

Estate of John Hunter•

IPA New Scientist Prize•

J & R Foundation•

Enid Barden and Aaron J. Jade Presidential Development Chair for New Scientists •

in memory of Cantor John Y. Jade

Liz and Alan Jaffe Endowment•

Jarndyce Foundation•

Dan Kane•

Mitchell T. Kaplan and Marilyn E. Jones•

Koret Foundation•

Prof. Daniel E. Koshland, Jr.•

The Henry Chanoch Krenter Institute for Biomedical Imaging and Genomics•

Larson Charitable Foundation New Scientist Fund•

Estate of Joseph and Erna Lazard•

Mr. and Mrs. Gary Leff•

Jacob and Charlotte Lehrman Foundation•

Leir Charitable Foundation•

Alvin and Gertrude Levine Career Development Chair•

Mr. and Mrs. Howard Levine•

Estate of Lela London•

Loundy Fund for New Scientists in memory of Jeanette and Mason Loundy•

Stan and Ellen Magidson•

Rhoda R. Mancher•

Robert Edward and Roselyn Rich Manson Career Development Chair•

Pascal and Ilana Mantoux•

Alan Markovitz•

Mrs. Judith Marks•

Dr. Karen Mashkin•

Rina Mayer•

Pearl Welinsky Merlo Foundation•

Morse Family Fund•

Dr. Ernst Nathan Fund for Biomedical Research•

Jordan and Jean Nerenberg Family Foundation Young Scientist Endowed Fund•

Selmo Nissenbaum•

William Z. and Eda Bess Novick New Scientists Fund•

Estate of Paul Ourieff•

Arnold and Diane Polinger Discovery Endowment Fund•

Hugo and Valerie Ramniceanu Foundation•

Robert Rees Applied Research Fund•

Henry S. & Anne S. Reich Research Fund for Mental Health•

Sam Revusky•

Abraham and Sonia Rochlin Foundation•

Hana and Julius Rosen Fund•

Lois Rosen New Scientist Fund•

Mike Rosenbloom Foundation•

Mr. and Mrs. Louis Rosenmayer•

Rosenzweig-Coopersmith Foundation•

Charles Rothschild•

Lord Sieff of Brimpton Memorial Fund•

Simms / Mann Family Foundation•

Skirball Chair for New Scientists•

Samuel M. Soref and Helene K. Soref Foundation•

South Florida Committee for the Weizmann Institute of Science “Brain Gain Fund”•

The late Rudolfine Steindling•

Swiss Society of Friends of the Weizmann Institute of Science•

Sam Switzer•

Louis and Fannie Tolz Collaborative Research Project•

Yael and Rami Ungar•

Sarah and Rolando Uziel•

Nathan, Shirley, Philip and Charlene Vener New Scientist Fund•

Dr. Albert Willner•

Robert and Francine Wiseman•

Jacques Wolf•

Wolfson Family Charitable Trust New Investigator Laboratories•

Jacques and Anita Zagury•

Natalie Zinn Haar Foundation•

Dr. Celia Zwillenberg-Fridman Fund for Young Scientists•

Scientist-specific funding:

Dr. Karen Michaeli

National Postdoctoral Award Program for Advancing Women in Science•

Dr. Michal Rivlin

Revson Awards towards the National Postdoctoral Award Program for Advancing •

Women in Science

Dr. Noam Stern-Ginossar

The Sir Charles Clore Research Prize•

National Postdoctoral Award Program for Advancing Women in Science•

Norman Huber•

Dr. Yaniv Ziv

Dr. and Mrs. Irving and Cherna Moskowitz•

Introducing New Scientists 2013-2014 is published by

the Department of Resource Development

at the Weizmann Institute of Science

P.O. Box 26, Rehovot, Israel 76100

Tel: 972 8 934 4582

e-mail: resource.development@weizmann.ac.il

Design and production: Dina Shoham Design

Cover photo: Yael Ilan