Searching for a Particle

English
 
In mid-December, as the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN), near Geneva, was winding up for the year, two of its groups, ATLAS and CMS, made an announcement. After a long search for the Higgs boson, both teams had discovered some anomalies in their data that may be traces of the elusive Higgs. While the results were not proof positive, the scientists involved in the project believe they are a very encouraging sign, raising hopes for more conclusive findings in the 2012 LHC run, set to begin in April.
Results of a collision that could represent a Higgs boson from the ATLAS experiment

 
Members of the Weizmann Institute’s Particle Physics and Astrophysics Department have been prominent participants in ATLAS. Prof. Giora Mikenberg was the ATLAS Muon Project leader for many years and now heads the Israeli LHC team. Prof. Ehud Duchovni heads the Weizmann ATLAS group as well as a small group looking for SUSY signals. And Prof. Eilam Gross is currently an ATLAS Higgs physics group convener. These three have been part of the effort to find the Higgs since 1987.

The Higgs boson is thought to be the particle that gives all the other elementary particles their mass. Predicted by the Standard Model of Particle Physics – a framework for all of the subatomic particles in nature – the Higgs is the one piece of the model that has not yet been proven to exist.

In 2011 the LHC particle accelerator in Geneva collided over 300 trillion (a million million) protons. Seven billion electron volts went into the effort to produce the Higgs boson. But in each collision, other, similar, particles are created. Gross: “There was no way to foresee what we would find. The chances of a collision producing a Higgs boson are so small that only about a hundred are expected to be observed in a year.”

The ATLAS results suggest that there could be a Higgs boson with a mass of around 126 GeV.
 
Prof. Ehud Duchovni’s research is supported by the Friends of Weizmann Institute in memory of Richard Kronstein; the Nella and Leon Benoziyo Center for High Energy Physics; and the Yeda-Sela Center for Basic Research. Prof. Duchovni is the incumbent of the Professor Wolfgang Gentner Professorial Chair of Nuclear Physics.

Prof. Eilam Gross’s research is supported by the Friends of Weizmann Institute in memory of Richard Kronstein.

Prof. Giora Mikenberg’s research is supported by the Nella and Leon Benoziyo Center for High Energy Physics, which he heads. Prof. Mikenberg is the incumbent of the Lady Davis Professorial Chair of Experimental Physics.



 
 
Results of a collision that could represent a Higgs boson from the ATLAS experiment
Space & Physics
English
  • CERN
  • Ehud Duchovni
  • Eilam Gross
  • Giora Mikenberg
  • Higgs boson
  • Large Hadron Collider
  • Particle Physics and Astrophysics

Phase III Clinical Trials of Diabetes Treatment

English
 
 
A treatment for Type 1 diabetes developed by Prof. Irun Cohen of the Institute’s Immunology Department has met both the primary and secondary goals of phase III clinical trials. Andromeda Biotech, which is licensed by Yeda Research and Development, Ltd. (the technology transfer arm of the Weizmann Institute) to develop the treatment, reported that it had been tested on 457 patients who had been diagnosed with Type 1 diabetes a short time before the trial. From the initial results, those who received the treatment – DiaPep277® – in the double-blinded test appeared to have significantly higher pancreas function than those in the control group. The trial took place over a period of two years, during which one group received DiaPep277® injections every three months and the control group was given a placebo. All received insulin, as needed, to control glucose levels.
Prof. Irun Cohen, DiaPep 227 developer
 
DiaPep277® is a unique peptide derived from the sequence of the human heat shock protein 60 (Hsp60). The peptide acts by modulating the immune system, preventing the destruction of the pancreatic cells that secrete insulin and preserving their natural function. Treatment of Type 1 diabetes patients with DiaPep277® may have several medical benefits: slowing the deterioration of the diseased tissue, improving metabolic control and reducing daily insulin requirements as well as the complications of diabetes.

The research and development team at Andromeda Biotech are currently working on a full assessment of the efficacy and safety data, and they are planning to conduct another clinical trial later this year.
 
Prof. Irun Cohen’s research is supported by the Laszlo N Tauber Family Foundation. 
 
 
Prof. Irun Cohen, DiaPep 227 developer
Life Sciences
English
  • Clinical trial
  • DiaPep277
  • Insulin
  • Irun Cohen
  • Type 1 diabetes
  • Yeda

Encryption while You Work

English
 
As computer data moves to the “cloud” – networks of shared, remote servers – security becomes more of a challenge. Ideally, users should be able to perform operations on their data with complete confidence that no one can peek over their virtual shoulders.
 
Prof. Shafi Goldwasser and Dr. Zvika Brakerski
 
Research carried out at the Weizmann Institute and MIT is moving us closer to the ability to work on data while it is still encrypted, giving an encrypted result that can later be securely deciphered.

“Until a few years ago, no one knew if the encryption needed for this sort of online security was even possible,” says Dr. Zvika Brakerski, who recently completed his Ph.D. in the group of Prof. Shafi Goldwasser of the Computer Science and Applied Mathematics Department. In 2009, the first so-called fully homomorphic encryption (FHE) was demonstrated.

That early version of fully homomorphic encryption was time-consuming and unwieldy. But Brakerski, together with Dr. Vinod Vaikuntanathan (who was a student of Goldwasser’s at MIT), surprised the computer security world last year with two papers in which they described several new ways of making fully homomorphic encryption more efficient. They not only simplified the arithmetic, speeding up processing time, but showed that a mathematical construct called an ideal lattice, used to generate the encryption keys, could be simplified without compromising security.
 
Their result promises to pave a path to applying FHE in practice.  Optimized versions of the new system could be hundreds – or even thousands – of times faster than the original construction. Indeed, Brakerski and Vaikuntanathan have managed to advance the theory behind fully homomorphic encryption to the point that computer engineers can begin to work on applications.
 
Prof. Shafrira Goldwasser’s research is supported by Walmart.

 
 
Prof. Shafi Goldwasser and Dr. Zvika Brakerski
Math & Computer Science
English
  • Computer Science and Applied Mathematics
  • Cryptography
  • Encryption
  • Shafi Goldwasser

Environmental Research Goes on the Road

English

 

(l-r) Drs. Eyal Rotenberg and David Asaf, Prof. Dan Yakir and Yakir Preisler. Lab on wheels

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
For the past decade, an extension of the Weizmann Institute – the Yatir research station – has been monitoring the atmosphere above a patch of forest in southern Israel, producing data on the exchange of water, carbon and energy between the atmosphere and the semiarid ecosystem. This station, the sole Israeli contribution to the global chain called FLUXNET, has generated scores of doctoral theses and scientific papers, as well as adding invaluable pieces to the picture of global climate change.

Yet the future of the station was uncertain; its long-term funding threatened to dry up. That is when a generous donor named Robert Lewis, together with his sister, Cathy Wills, stepped into the breach with a promise to provide support for the station for the next ten years. In fact, Lewis was so impressed with the work being done there that he asked the head of the project, Prof. Dan Yakir of the Environmental Sciences and Energy Research Department in the Faculty of Chemistry: “What else do you need to develop this research?” Yakir’s reply was prompt: “We would like to be able to be mobile.”

Thus was the Biosphere-Atmosphere Research Mobile Lab born. The gestation period was a long one: Together with Dr. Eyal Rotenberg, Yakir and their team have spent the last two years designing and assembling the lab from the chassis up. All of the equipment has been custom-built, and a slew of engineers and experts from a dozen companies have been involved in the project. In the process, the researchers found they had to become truck drivers as well as scientists – Yakir, Rotenberg and several of the crew are now licensed, and they have begun to figure diesel and maintenance costs into their research budget.

“Eventually,” says Yakir, “the mobile lab will become our main lab, and much of the work conducted today both at Yatir and in our Weizmann Institute lab will be carried out there. In the future, it will do everything the ten-year-old Yatir station can do and more.” Along with the computers and scientific gear, the lab hauls a huge telescopic mast that can raise equipment up to 30 meters in the air – 10 meters higher than the tower at Yatir – enabling researchers to study the atmosphere above the relatively tall canopies of Israel’s northern forests.

In addition to ongoing scientific research, Yakir would like to see the mobile lab used in various educational projects at the Weizmann Institute. “It’s often hard to get students excited about global climate science,” he says. “A mobile lab outside the classroom gives them the opportunity to see the cool equipment that is used in our research, and the real-time measurements on the computer screens could make the subject both immediate and attractive.” In the meantime, the FLUXNET organization has already invited Yakir to bring the lab to Europe, where they would like it to travel between the many fixed stations to check and calibrate them.
 
 
Prof. Dan Yakir’s research is supported by the Cathy Wills and Robert Lewis Program in Environmental Science; and the estate of Sanford Kaplan.

 

 
 
 
 
(l-r) Drs. Eyal Rotenberg and David Asaf, Prof. Dan Yakir and Yakir Preisler. Lab on wheels
Environment
English
  • Carbon dioxide
  • Dan Yakir
  • Environmental Sciences and Energy Research
  • FLUXNET
  • Yatir forest

Still at Large: WIMPs

English

 

XENON100 dark matter detector
 
 
 
 
 
 
 
 
 

 

The existence of particles known as WIMPs is still up in the air. The WIMP, or Weakly Interacting Massive Particle, is one candidate for the mysterious dark matter thought to make up much of our universe. Such a particle would hardly ever interact with regular, everyday matter and thus should be extremely hard to detect.

 
Weizmann Institute scientists have been participating in an experiment to look for traces of WIMPs. The experiment consists of 161 kilos of liquid xenon buried deep underground in Italy’s Gran Sasso National Lab. Besides the 1400 meters of rock, layers of copper, water, lead and polyethylene shield the experiment from cosmic and background radiation, so that any rare WIMP signals can be recorded. Working with 60 physicists from around the globe, Profs. Eilam Gross, Ehud Duchovni and Amos Breskin of the Institute’s Particle Physics and Astrophysics Department were instrumental in increasing both the search sensitivity of the experiment and the possibility of discovering the particles.
 
(l-r) Ofer Vitells, and Profs. Amos Breskin, Eilam Gross and Ehud Duchovni. Waiting for dark matter
 

After 100 days of operation, three candidate events were recorded, but these could well have been rare background radiation events within the xenon tank. Because XENON100 was the most sensitive of the WIMP searches conducted in various labs around the world, it has narrowed the possible range for this particle. Now the scientists are working on a new version of the detector that will contain 1000 kilos of liquid xenon and be a hundred times more sensitive.

 

Prof. Amos Breskin's research is supported by the Nella and Leon Benoziyo Center for High Energy Physics; and the estate of Richard Kronstein. Prof. Breskin is the incumbent of the Walter P. Reuther Chair of Research in Peaceful Uses of Atomic Energy.
 
 
Prof. Ehud Duchovni's research is supported by the Nella and Leon Benoziyo Center for High Energy Physics; and the Yeda-Sela Center for Basic Research.
 
Prof. Eilam Gross's research is supported by the estate of Richard Kronstein.
 
 
 
(l-r) Ofer Vitells, and Profs. Amos Breskin, Eilam Gross and Ehud Duchovni. Waiting for dark matter
Space & Physics
English
  • Amos Breskin
  • Dark matter
  • Ehud Duchovni
  • Eilam Gross
  • Particle Physics
  • Particle detector

Spinning off DNA

English
 
 
(l-r) Tal Markus, and Profs. Zeev Vager and Ron Naaman. Putting a spin on it
 
Biological molecules and quantum systems are not just apples and oranges – they’re more like apple trees and cans of frozen orange juice. The two exist in completely different conditions, on completely different scales. Yet research by Prof. Ron Naaman of the Chemical Physics Department (Faculty of Chemistry), conducted together with scientists at the Weizmann Institute and in Germany, definitively shows that a biological molecule – DNA – can discern between the quantum states known as spin in such subatomic particles as electrons.

Biological molecules are chiral: They exist in either “left-” or “right-handed” forms that can’t be superimposed on one another. Double-stranded DNA molecules are doubly chiral – both in the arrangement of the individual strands and in the direction of their helical twists. Naaman, together with Prof. Zeev Vager of the Particle Physics and Astrophysics Department, research student Tal Markus, and Prof. Helmut Zacharias and his research team at the University of Münster, Germany, thought that this chirality might imbue DNA with spin-selective properties. Their findings appeared in Science.

The researchers exposed DNA to groups of electrons with both directions of spin. Indeed, the team’s results surpassed expectations: The biological molecules reacted strongly with the electrons carrying one of those spins, and hardly at all with the others. Their findings imply that the chiral nature of the DNA molecule somehow “sets the preference” for the spin of electrons moving through it.

The team’s findings could have relevance for both biomedical research and the field of spintronics. For instance, if further studies bear out the finding that DNA sustains damage only from spins pointing in one direction, then medical radiation exposure might be reduced and devices designed accordingly. On the other hand, DNA and other biological molecules could become a central feature of new types of spintronic devices that will work on particle spin rather than electric charge, as they do today.
 
Prof. Ron Naaman heads the Nancy and Stephen Grand Research Center for Sensors and Security; his research is also supported by the estate of Theodore Rifkin; and Rachel Schwartz, Canada. Prof. Naaman is the incumbent of the Aryeh and Mintzi Katzman Professorial Chair.
 
 
 
(l-r) Tal Markus, and Profs. Zeev Vager and Ron Naaman. Putting a spin on it
Chemistry
English
  • Chemical Physics
  • Chiral
  • DNA
  • Particle Physics
  • Ron Naaman
  • Spin›Spintronics
  • Zeev Vager

Take the Axon Train

English
 
A developing eye of the fruit fly (left) is connected by the optic stalk to the optic lobe in the fly’s brain
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
If the body of a nerve cell were a meter wide, some of its extensions, called axons, would stretch for dozens of miles. Yet signaling molecules, as well as other substances made in the body of the cell, are effectively transported along these axons.
 
Until now, such molecules were known to “ride” to the end of an axon along a rigid internal framework known as the cytoskeleton.
 
Weizmann Institute scientists have now demonstrated the existence of an entirely new means of transportation inside nerve cells. They showed that molecules can also travel in the cell’s endoplasmic reticulum – a large cellular compartment known to store or even manufacture various chemicals – that envelops the nucleus but also extends along the cytoskeleton to various parts of the cell. This discovery, recently published in PLoS Biology, emerged from research conducted by graduate student Shaul Yogev with Dr. Eyal Schejter in the laboratory of Prof. Ben-Zion Shilo of the Molecular Genetics Department.
 
The scientists focused on a signaling molecule that is crucial for communication between the eye and the brain in fruit fly larvae. They found that this signaling molecule, a type of epidermal growth factor, travels from the body of the nerve cell to the tip of the axon inside the endoplasmic reticulum. It is accompanied by two helpers: a “chaperone” that protects it from damage and an enzyme that clips the signaling molecule as it reaches the tip of the axon, so that it can leave the nerve cell.
 
The researchers then tried removing the clipping enzyme from the endoplasmic reticulum, preventing the release of the signaling molecule. They thus confirmed that the molecule’s regular route should indeed be through the reticulum and not through any other part of the cell.
 
Though the study was conducted in the fruit fly, its findings are thought to apply to mammals, including humans. Clarifying how signals are transported in nerve cells is crucial for understanding their functioning in health and disease.
 
Shaul Yogev and Dr. Eyal Schejter. A new way to travel

 

 

 

 

 

 

 

 

 

 

 

 

 

Prof. Ben- Zion Shilo's research is supported by the Jeanne and Joseph Nissim Foundation for Life Sciences Research; the Carolito Stiftung; la Fondation Raphael et Regina Levy; and the estate of Georg Galai. Prof. Shilo is the incumbent of the Hilda and Cecil Lewis Professorial Chair of Molecular Genetics.


 

 
A developing eye of the fruit fly (left) is connected by the optic stalk to the optic lobe in the fly’s brain
Life Sciences
English
  • Axon
  • Ben-Zion Shilo
  • Fruit fly
  • Molecular Genetics
  • Nerve cell
  • Signaling

GOT to Prevent Brain Damage

English
Prof. Vivian Teichberg. New support for the approach

 

Two studies recently conducted in Spain provide conclusive evidence for the effectiveness of a novel approach, developed at the Weizmann Institute, to treating stroke, head trauma and other diseases of the brain.
 
In 2003, Prof. Vivian I. Teichberg of the Neurobiology Department demonstrated a way to remove excess glutamate – a short-lived neurotransmitter – from the brain. Glutamate gets overproduced by injured brain cells, and the overdose kills off yet more cells. Teichberg knew that the body maintains a balance between glutamate levels in the blood and in the brain, and he hypothesized that removing glutamate from the blood would force tiny pumps (called transporters) on the brain’s blood vessels to shunt glutamate out of the brain and into the blood. By 2007, he and his colleagues had shown that rats given GOT – an enzyme that “scavenges” glutamate from blood – were protected against the worst damage from head trauma.
 
In the first of the new studies, Fransisco Campos and others in the lab of Prof. Jose Castillo, the University of Santiago de Compostela, Spain, worked with animal models of stroke. Injecting rats with a blood glutamate scavenger reduced glutamate levels in the brain, and also lessened cell death and swelling. In the second study, hospital neurologists in Spain tested newly admitted stroke patients for blood glutamate and GOT, and they found these two substances to be the best predictors of recovery at three months. High glutamate levels correlated with a poorer prognosis, high GOT levels with a better one.
 
A number of diseases, including Alzheimer’s, Parkinson’s and even some brain tumors involve elevated glutamate levels in the brain, and human GOT might, in the future, be used to treat a wide range of problems. Yeda, the technology transfer arm of the Weizmann Institute, holds a patent for this method.
 
Prof. Vivian I. Teichberg's research is supported by the Nella and Leon Benoziyo Center for Neurosciences; the Carl and Micaela Einhorn-Dominic Brain Research Institute; and the Legacy Heritage Fund Program of the Israel Science Foundation. Prof. Teichberg is the incumbent of the Louis and Florence Katz-Cohen Professorial Chair of Neuropharmacology.
 

 
 
Prof. Vivian Teichberg. New support for the approach
Life Sciences
English
  • Brain injury
  • Vivian Teichberg

Wild Strawberry Secrets Revealed

English

Woodland strawberry. Image courtesy of H. Zell, Wikimedia commons

                                                                                                                                                                                                                                                                                               
In a collaborative effort involving 74 researchers from 38 research institutes, scientists have produced the full genome of the woodland strawberry. The research appeared in Nature Genetics. Drs. Asaph Aharoni and Avital Adato of the Weizmann Institute’s Plant Sciences Department were the sole Israeli scientists participating in the project, but they made a major contribution in mapping the genes and gene families responsible for the strawberry’s flavor and aroma.

Aharoni has, for a number of years, been investigating the metabolic pathways of ripening, in which the substances that give the fruit its flavor and aroma are produced. He was one of the first to use biological chips (i.e., microarrays) to analyze genetic networks – including the ones involved in creating these substances – and he has also conducted a comparative analysis of these genes in wild and cultivated plants. Now that the full genome of the wild strawberry plant is available for research, he is able not only to conduct deeper and broader investigations but to shed new light on some of his past findings. For instance, a computerized analysis of the woodland strawberry genome revealed that an enzyme that Aharoni had previously characterized belongs to a relatively small family. This enzyme family is responsible for the production of a large number of aroma substances that provide the fruity notes in the strawberry’s flavor, and the finding helped clarify the means of production of these substances.
 
Aharoni hopes that, among other things, the newly sequenced genome will help scientists understand how to return the flavors and aromas that have been lost over years of breeding in the cultivated cousin of the wild strawberry. The intense, concentrated aroma and flavor of the woodland strawberry are, he says, something to aspire to.
 

Dr. Asaph Aharoni's research is supported by the Minna James Heineman Stiftung; and Roberto and Renata Ruhman, Brazil. Dr. Aharoni is the incumbent of the Adolfo and Evelyn Blum Career Development Chair of Cancer Research in Perpetuity.


 
Woodland strawberry. Image courtesy of H. Zell, Wikimedia commons
Environment
English
  • Asaph Aharoni
  • Genome
  • Plant Sciences

Engineered Enzyme Protects against Nerve Gas

English

A multidisciplinary team of scientists at the Weizmann Institute of Science succeeded in developing an enzyme that efficiently breaks down certain forms of nerve gas before damage to nerves and muscles can ensue. Their results were published in Nature Chemical Biology.
 
Agents in the gas disrupt the chemical messages sent between nerve and muscle cells, causing loss of muscle control and ultimately leading to death by suffocation. These substances interfere with the activity of acetylcholinesterase, the enzyme responsible for the breakdown of the chemical messenger – acetylcholine. As a result, acetylcholine continues to exert its effect, resulting in protracted muscle contractions throughout the body. Enzymes had been identified that are able to break down similar nerve agents, but these work inefficiently, making their use impractical.
 

Prof. Dan Tawfik of the Weizmann Institute’s Biological Chemistry Department and his group developed a special method to induce “natural selection” of enzymes in a test tube, enabling them to engineer tailor-made enzymes. Tawfik showed that this method can improve the efficiency of enzymes by factors of hundreds and even thousands.
 
The new mutant enzymes have been structurally analyzed by a team of scientists from the Structural Biology Department that included Profs. Joel Sussman and Israel Silman and research student Moshe Ben-David. Further experiments at USAMIRD labs have shown that when these enzymes were given preventively, they afforded animals near-complete protection against two types of nerve agents, even at relatively high exposures.
 
Prof. Dan Tawfik's research is supported by the Helen and Martin Kimmel Award for Innovative Investigation; the Willner Family Leadership Institute for the Weizmann Institute of Science; the Sassoon and Marjorie Peress Philanthropic Fund; Miel de Botton Aynsley, UK; Yossie Hollander, Israel; and Roberto and Renata Ruhman, Brazil. Prof. Tawfik is the incumbent of the Nella and Leon Benoziyo Professorial Chair.

Prof. Joel Sussman's research is supported by the Jean and Jula Goldwurm Memorial Foundation; the S. & J. Lurje Memorial Foundation; the Nalvyco Trust; Mr. Harold Chefitz, Livingston, NJ; Mr. and Mrs. Yossie Hollander, Israel; Nicolas and Elsa Neuman, Mexico; Dr. Ze'ev Rav-Noy, Los Angeles, CA; the Bruce and Rosalie N. Rosen Family Foundation; and Harry Sussman, Woodbury, NY. Prof. Joel Sussman is the incumbent of the Morton and Gladys Pickman Professorial Chair in Structural Biology.
Life Sciences
English
  • AChE
  • AChE›AChE
  • Biological Chemistry
  • Dan Tawfik
  • Enzyme
  • Evolution
  • Israel Silman
  • Joel Sussman
  • Nerve gas
  • Structural Biology

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