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Novel technique reveals the intricate beauty of a cracked glass

31/10/2017

Physics, math and special gels explain the formation of fracture patterns in brittle materials

Researchers have long pondered the origin of delicate criss-cross facetted patterns that are commonly found on the surfaces of broken material. Typical crack speeds in glass easily surpass a kilometer per second, and broken surface features may be well smaller than a millimeter. Since the formation of surface structure lasts a tiny fraction of a second, the processes generating these patterns have been largely a mystery.

Now there is a way around this problem. Replacing hard glass with soft but brittle gels makes it possible to slow down the cracks that precipitate fracture to mere meters per second. This novel technique has enabled researchers Itamar Kolvin, Gil Cohen and Prof. Jay Fineberg, at the Hebrew University of Jerusalem’s Racah Institute of Physics, to unravel the complex physical processes that take place during fracture in microscopic detail and in real time.

Their work sheds new light on how broken surface patterns are formed. Surface facets bounded by steps are formed due to a special “topological” arrangement of the crack that cannot easily be undone, much as a knot along a string cannot be unraveled without pulling the whole length of the string through it.

These “crack knots” increase the surface formed by a crack, thereby creating a new venue for dissipating the energy required for material failure, and thereby making materials harder to break. 

“The complex surfaces that are commonly formed on any fractured object have never been entirely understood,” said Prof. Jay Fineberg. “While a crack could form perfectly flat, mirror-like fracture surfaces (and sometimes does), generally complex facetted surfaces are the rule, even though they require much more energy to form. This study illuminates both how such beautiful and intricate patterns emerge in the fracture process, and why the crack cannot divest itself of them once they are formed.”

This physically important process provides an aesthetic example of how physics and mathematics intertwine to create intricate and often unexpected beauty. The research appears in Nature Materials.

The Hebrew University of Jerusalem is Israel’s leading university and premier research institution. Founded in 1918 by innovative thinkers including Albert Einstein, the Hebrew University is a pluralistic institution that advances science and knowledge for the benefit of humankind. For more information, please visit http://new.huji.ac.il/en.

Files for download:

FUNDING: Fineberg and Kolvin acknowledge the support of the Israel Science Foundation (grant no.1523/15), as well as the US-Israel Bi-national Science Foundation (grant no. 2016950).

CITATION: Itamar Kolvin, Gil Cohen, Jay Fineberg. Topological defects govern crack front motion and facet formation on broken surfaces. Nature Materials, Advance Online Publication October 16, 2017. doi:10.1038/nmat5008. Link: http://dx.doi.org/10.1038/nmat5008

Novel technique reveals the intricate beauty of a cracked glass
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Mrs. Lily Safra Dedicates the New Home of Hebrew University's Edmond and Lily Safra Center for Brain Sciences (ELSC)

02/07/2017

Mayor of Jerusalem Nir Barkat, British Architect Lord Norman Foster, and more than 400 friends and supporters joined the gala celebration and naming ceremony of Israel’s largest neuroscience center

Video: ‘ELSC — The Next Generation of Brain Research’

More than 400 friends and supporters joined Mrs. Lily Safra as she dedicated the new home of the Edmond and Lily Safra Center for Brain Sciences (ELSC) at the Hebrew University of Jerusalem's Edmond J. Safra Campus.

The Mayor of Jerusalem, Nir Barkat, and Lord Norman Foster, Founder and Executive Chairman of the British architectural firm Foster + Partners, which designed the new Center, were among the dignitaries attending the gala event.

“I am thrilled to join in celebrating this defining moment for ELSC when such an extraordinary new building becomes home to a remarkable community of researchers and students,” said Mrs. Lily Safra. “Their multi-disciplinary study of the brain's secrets will surely make a profound impact on how we treat disease and care for patients. I know that my husband Edmond would share my deep sense of pride that our names are associated with such pioneering work, and with such dedicated and inspiring people."

Mrs. Safra is a leading supporter of neuroscience research projects around the world, and Chairwoman of the Edmond J. Safra Foundation, which pledged a lead donation of $50 Million of the Center’s $150 Million initial budget.

“The Hebrew University is grateful to Mrs. Lily Safra and the Edmond J. Safra Foundation for their leadership in this historic initiative to unlock the mysteries of the brain,” said Prof. Menahem Ben-Sasson, President of the Hebrew University.  “ELSC is unique in the way it brings together theoretical and experimental researchers to develop pioneering approaches to brain science.”

The 14,500 square-meter Center is a premier setting that will encourage effective collaboration through interdisciplinary collaboration and interaction. Specialists in disciplines such as physics, computer science, psychology, neurobiology and medicine will all work under one roof to achieve breakthroughs that improve the lives of patients suffering from illnesses of the brain.

Directed by Prof. Israel Nelken and Prof. Adi Mizrahi, the Center will include state-of-the-art labs, classrooms, an innovative imaging center, and areas for biological and pre-clinical research. Significant emphasis was placed on constructing an environmentally friendly building with a focus on conserving energy and reducing carbon dioxide emissions.  

Video: “ELSC — The Next Generation of Brain Research” can be viewed at https://youtu.be/JRibYsXS0lw

Photos for Download:
  • http://media.huji.ac.il/new/photos/hu170613_elsc-3.jpg - Mrs. Lily Safra cuts the ribbon to dedicate the new home of the Edmond and Lily Safra Center for Brain Science, accompanied by (from left) British architect Lord Norman Foster, Chairman of the Hebrew University's Board of Governors Mr. Michael Federmann, Mayor of Jerusalem Nir Barkat, and Hebrew University President Prof. Menahem Ben-Sasson. (Credit: Michael Zekri for Hebrew University) 
  • http://media.huji.ac.il/new/photos/hu170613_elsc-5.jpg - Mayor of Jerusalem Nir Barkat speaks at the dedication of the new home of the Edmond and Lily Safra Center for Brain Science (Credit: Bruno Charbit for Hebrew University) 
  • http://media.huji.ac.il/new/photos/hu170613_elsc-6.JPG - (From left) ELSC scientist Prof. Idan Segev, Member of the Council for Higher Education and Chairman of the Planning and Budgeting Committee Prof. Yaffa Zilbershats, Hebrew University Rector and President-elect Prof. Asher Cohen, and ELSC researcher Prof. Eilon Vaadia. (Credit: Bruno Charbit for Hebrew University)
  • http://media.huji.ac.il/new/photos/hu170613_elsc-9.jpg - Interior photo of the new brain sciences building at the Edmond and Lily Safra Center for Brain Sciences (Credit: Michael Zekri for Hebrew University) 
  • http://media.huji.ac.il/new/photos/hu170613_elsc-12.jpg - Exterior photo of the new brain sciences building at the Edmond and Lily Safra Center for Brain Sciences (Credit: Michael Zekri for Hebrew University)
  • http://media.huji.ac.il/new/photos/hu170316_elsc-11.jpg - The facade of the new home of the Edmond and Lily Safra Center for Brain Science, depicting neuronal connections in the brain. (Credit: Foster + Partners / Hebrew University)

About the Edmond and Lily Safra Center for Brain Sciences

ELSC’s mission is to achieve a comprehensive understanding of brain mechanisms by developing a thriving interface between theoretical and experimental neuroscience. Harnessing the extraordinary opportunities created by advances in technology and medicine, ELSC is shaping the next generation of researchers to advance the brain sciences and transform the treatment of neurological and psychiatric disorders. By building bridges across disciplines—combining high-resolution studies of local neuronal circuits (from genes to neurons and synapses) with a global theory of the brain’s computational principles—ELSC aims to be at the forefront of neuroscience research worldwide. ELSC was founded with the generous support of the Edmond J. Safra Philanthropic Foundation, which supports hundreds of organizations in more than 40 countries around the world. For more information, please visit http://elsc.huji.ac.il.

About the Hebrew University of Jerusalem

The Hebrew University of Jerusalem, Israel’s leading academic and research institution, is ranked among the top 100 universities in the world. Founded in 1918 by visionaries including Albert Einstein, the Hebrew University is a pluralistic institution where science and knowledge are advanced for the benefit of humankind. For more information, please visit http://new.huji.ac.il/en

Mrs. Lily Safra Dedicates the New Home of Hebrew University's Edmond and Lily Safra Center for Brain Sciences (ELSC)
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Researchers find micro-gene that protects the brain from developing epilepsy

06/06/2017
Increased levels of a micro-RNA could have a protective effect that explains why identical stressors trigger seizures in some people but not in others

On December 16, 1997, hundreds of Japanese children were brought to hospital suffering from epilepsy-like seizures. They all had one thing in common: they had been watching an episode of the Pokémon TV show when their symptoms began. Doctors determined that their symptoms were triggered by five seconds of intensely bright flashing lights on the popular TV program. But why did the lights affect a few hundred children while thousands of other viewers were unharmed?

In new research published in the Proceedings of the National Academy of Sciences, a team of researchers headed by Prof. Hermona Soreq at the Hebrew University of Jerusalem sought to answer this question. Drawing on her previous research, Prof. Soreq, the Charlotte Slesinger Professor of Molecular Neuroscience at the Edmond and Lily Safra Center for Brain Sciences and the Alexander Silberman Institute of Life Sciences, hypothesized that healthy brains may be protected from epileptic seizures by rapidly produced molecules called short RNAs, or microRNAs (miRs). MicroRNAs are a recently-discovered class of non-coding RNAs that can prevent genes from expressing particular proteins.

To test this idea, Soreq and her colleagues at the Hebrew University developed a transgenic mouse producing unusually high amounts of one micro-RNA called miR-211, which the researchers predicted was involved. The levels of this molecule could be gradually lowered by administering the antibiotic Doxycycline, enabling tests of its potency to avoid epilepsy.

Working with colleagues at Ben-Gurion University of the Negev in Israel and Dalhousie University in Canada, they suppressed excess miR-211 production in the engineered mice to the levels found in normal brains. Within four days, this caused the mice to display electrically-recorded epilepsy and hypersensitivity to epilepsy-inducing compounds.  “Dynamic changes in the amount of miR-211 in the forebrains of these mice shifted the threshold for spontaneous and pharmacologically induced seizures, alongside changes in the cholinergic pathway genes,” said Prof. Soreq.

These findings indicated that mir-211 plays a beneficial role in protecting the brain from epileptic seizures in the engineered mice.

Noting that miR-211 is known to be elevated in the brains of Alzheimer's patients who are at high risk for epilepsy, the researchers suspect that in human brains as well, elevated miR-211 may act as a protective mechanism to reduce the risk of epileptic seizures.

“It is important to discover how only some people’s brains present a susceptibility to seizures, while others do not, even when subjected to these same stressors,” said Prof. Soreq. In searching for the physiological mechanisms that allow some people’s brains to avoid epilepsy, we found that increased levels of micro-RNA 211 could have a protective effect.”

According to the researchers, recognizing the importance of miR-211 could open new avenues for diagnosing and interfering with epilepsy. By understanding how miR-211 affects seizure thresholds, scientists could potentially develop therapeutics that lead to greater miR-211–production.

Participating researchers are affiliated with the following institutions: The Alexander Silberman Institute of Life Sciences and The Edmond and Lily Safra Center for Brain Sciences at The Hebrew University of Jerusalem, Israel; Department of Physiology and Cell Biology and Department of Cognitive and Brain Sciences, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev; and Department of Medical Neuroscience, Dalhousie University, Canada. The authors thank the Netherlands Brain Bank for human-derived samples.

The Hebrew University of Jerusalem is Israel’s leading academic and research institution, producing one-third of all civilian research in Israel. For more information, visit http://new.huji.ac.il/en.

# # #

CITATION: Dynamic changes in murine forebrain miR-211 expression associate with cholinergic imbalances and epileptiform activity. Uriya Bekenstein, Nibha Mishra, Dan Z. Milikovsky, Geula Hanin, Daniel Zelig, Liron Sheintuch, Amit Berson, David S. Greenberg, Alon Friedman, and Hermona Soreq. PNAS Early Edition, June 5, 2017. Doi:10.1073/pnas.1701201114. Link: www.pnas.org/cgi/doi/10.1073/pnas.1701201114

SUPPORT: The research was supported by grants to various researchers from: European Research Council Advanced Award 321501; European Union’s Seventh Framework Program FP7/2007–2013 Grant 602102, EPITARGET; Israeli Ministry of Science, Technology and Space Grant 53140; Legacy Heritage Science Initiative of the Israel Science Foundation Grants 817/13 and 717/15; the Planning and Budgeting Committee Q:35 and the Edmond and Lily Safra Center for Brain Sciences postdoctoral fellowship; and the Howard and Diana Wendy Pre-doctoral Fellowship. 

- Dov Smith

Researchers find micro-gene that protects the brain from developing epilepsy
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Bacteria Sleep, Then Rapidly Evolve, to Survive Antibiotic Treatments

13/02/2017

Hebrew University biophysicists used quantitative approaches from Physics to understand issues in Biology

Antibiotic resistance is a major and growing problem worldwide. According to the World Health Organization, antibiotic resistance is rising to dangerously high levels in all parts of the world, and new resistance mechanisms are emerging and spreading globally, threatening our ability to treat common infectious diseases. But how these bacterial resistance mechanisms occur, and whether we can predict their evolution, is far from understood.

Researchers have shown (http://new.huji.ac.il/en/article/22060) that one way bacteria can survive antibiotics is to evolve a “timer” that keeps them dormant for the duration of antibiotic treatment. But the antibiotic kills them when they wake up, so the easy solution is to continue the antibiotic treatment for a longer duration.

Now, in new research published in the prestigious journal Science, researchers at the Hebrew University of Jerusalem report a startling alternative path to the evolution of resistance in bacteria. After evolving a dormancy mechanism, the bacterial population can then evolve resistance 20 times faster than normal. At this point, continuing to administer antibiotics won't kill the bacteria.

To investigate this evolutionary process, a group of biophysicists, led by Prof. Nathalie Balaban and PhD student Irit Levin-Reisman at the Hebrew University’s Racah Institute of Physics, exposed bacterial populations to a daily dose of antibiotics in controlled laboratory conditions, until resistance was established. By tracking the bacteria along the evolutionary process, they found that the lethal antibiotic dosage gave rise to bacteria that were transiently dormant, and were therefore protected from several types of antibiotics that target actively growing bacteria. Once bacteria acquired the ability to go dormant, which is termed “tolerance,” they rapidly acquired mutations to resistance and were able to overcome the antibiotic treatment.

Thus, first the bacteria evolved to "sleep" for most of the antibiotic treatment, and then this "sleeping mode" not only transiently protected them from the lethal action of the drug, but also actually worked as a stepping stone for the later acquisition of resistance factors.

The results indicate that tolerance may play a crucial role in the evolution of resistance in bacterial populations under cyclic exposures to high antibiotic concentrations. The key factors are that tolerance arises rapidly, as a result of the large number of possible mutations that lead to it, and that the combined effect of resistance and tolerance promotes the establishment of a partial resistance mutation on a tolerant background.

These findings may have important implications for the development of new antibiotics, as they suggest that the way to delay the evolution of resistance is by using drugs that can also target the tolerant bacteria.

Unveiling the evolutionary dynamics of antibiotic resistance was made possible by the biophysical approach of the research team. The experiments were performed by a team of physicists, who developed a theoretical model and computer simulations that enabled a deep understanding of the reason behind the fast evolution of resistance that were observed.

Researchers involved in the research are affiliated with the Racah Institute of Physics and the Harvey M. Kruger Family Center for Nanoscience and Nanotechnology at the Hebrew University of Jerusalem, and the Broad institute of Harvard and MIT.

FUNDING: The work was supported by the European Research Council (Consolidator Grant no. 681819) and Israel Science Foundation (492/15). ILR acknowledges support from the Dalia and Dan Maydan Fellowship.

CITATION: Antibiotic tolerance facilitates the evolution of resistance. Irit Levin Reisman, Irine Ronin, Orit Gefen, Ilan Braniss, Noam Shoresh and Nathalie Q. Balaban. Science, February 9, 2017. doi: 10.1126/science.aaj2191. (Paper will be published online at http://science.sciencemag.org/lookup/doi/10.1126/science.aaj2191.)

Bacteria Sleep, Then Rapidly Evolve, to Survive Antibiotic Treatments
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Mortimer B. Zuckerman Announces Transformative Program to Support Future Generations of American & Israeli Leaders In Science, Technology, Engineering and Math Fields

25/01/2016

American business leader and philanthropist Mortimer Zuckerman announced today the launch of the Zuckerman STEM Leadership Program, a transformative initiative designed to support future generations of leaders in science, technology, engineering and math in the United States and Israel and, over time, foster greater collaboration between two of the world’s most advanced scientific research centers.

The Zuckerman STEM Leadership Program will give the highest-achieving American post-doctoral researchers and graduate students the ability to collaborate with leading researchers at Israel’s top research institutions — the Hebrew University of Jerusalem; the Technion-Israel Institute of Technology; Tel Aviv University; and the Weizmann Institute of Science — which are among the world’s most advanced.  

By providing American graduate students and post-doctoral researchers with exposure to Israel’s renowned cutting-edge research and startup culture, the Zuckerman STEM Leadership Program will raise a generation of academic, scientific and industry leaders in the United States infused with a unique spirit of entrepreneurship and innovation. The program will simultaneously bolster Israeli research institutions as world-leading centers for cutting edge research by providing Israeli institutions access to large-scale funding needed to develop top-tier research labs, projects and programs.

“At a time when collaboration is essential to advanced scientific research, this program gives the next generations of leading American and Israeli academics the ability to work together on cutting edge research in ways that stand to benefit their fields for years to come,” said Mr. Zuckerman. “The result will help transform not just the work of the scholars involved, but the way the United States and Israel approach collaboration and cooperation across the sciences.”

“Mort’s friendship is demonstrated yet again through this important initiative,” said Prime Minister of Israel Benjamin Netanyahu. “Together with the Technion, The Weizmann Institute, The Hebrew University and Tel Aviv University, this project will help bring back home some of Israel’s most brilliant sons and daughters, allow them to advance their own careers here and in so doing contribute to Israel’s growing scientific excellence. It will also enable some of America’s brightest young scientists to conduct their research in Israel.

“New York and Israel share a deep and unparalleled connection – and the Zuckerman Scholars Program is a prime example of how we can keep that relationship strong today and in the future,” said New York Governor Andrew Cuomo. “By helping some of America’s best and brightest students work and learn alongside leading researchers in Israel, this program gives us a new model for cooperation and partnership that will ultimately better society as a whole. This is a great way to strengthen the bond between Israel and the Empire State, and I applaud Mort Zuckerman for launching this program today.”

“Science is the only language with no borders or limits; it belongs to all,” said Prof. Menahem Ben-Sasson, President of The Hebrew University of Jerusalem. “The new Zuckerman initiative will strengthen connections between two important academic communities, North America and Israel, at a critical juncture – that where a new generation of scientists begin their careers, who will develop with roots firmly planted in the best institutions in both regions and will continue throughout their careers as catalysts for collaboration, enriching both Israeli and North American science and advancing knowledge for the benefit of humanity.”

The Zuckerman STEM Leadership Program will be supported by funding from Mr. Zuckerman’s foundation to inaugurate the program and ensure that the first class of Zuckerman Scholars will begin with the 2016–2017 academic year. The foundation’s long-term intent is to ensure that the Zuckerman Scholars and the program’s related educational activities continue in perpetuity. In the next twenty years alone, the program intends to provide over $100 million in scholarships and related educational activities that will benefit not only the participating scholars and universities, but the general public as well.

The Zuckerman STEM Leadership Program will, over time, help strengthen the U.S.-Israel partnership as Zuckerman Scholars return to the United States after building long-lasting relationships based in mutual collaboration. Israeli academic leaders returning to research institutions in Israel will similarly advance the overarching collaborative effort in science between the two nations as they continue to build bridges with their American colleagues.

The Zuckerman Scholars Program will initiate with the two main tracks: (1) the Postdoctoral Scholars Program, which is open to highest-achieving postdoctoral researchers from the United States to pursue research at leading Israeli research institutions; and (2) Zuckerman Faculty Scholars, which is designed to support Israeli academic leaders by fostering world-class labs, programs and projects at the Israeli institutions.

Additional information on the program, including how to apply, is available through the program’s website at http://zuckerman-scholars.org.

Mortimer B. Zuckerman Announces Transformative Program to Support Future Generations of American & Israeli Leaders In Science, Technology, Engineering and Math Fields
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Mortimer B. Zuckerman honored for $100 Million STEM Initiative

16/01/2017

Donation by Zuckerman Institute will herald unprecedented collaboration between Israel’s major research universities

The President of the State of Israel, Reuven Rivlin, honored the American business leader and philanthropist Mortimer B. Zuckerman at the President's Residence in Jerusalem today, for the Zuckerman Institute’s $100 million initiative to provide scholarships to the next generation of STEM leaders in the United States and Israel. 

Photo, L to R: http://media.huji.ac.il/new/photos/hu170116_zuckerman.jpg - Prof. Hanoch Gutfreund, former president of the Hebrew University, Mortimer B. Zuckerman, and Prof. Asher Cohen, rector of the Hebrew University, at the President's Residence on January 16, 2017 (Photo: Israel Hadari)

Mortimer Zuckerman launched the Zuckerman STEM Leadership Program to support future generations of leaders in Science, Technology, Engineering and Math in the United States and Israel and, over time, foster greater collaboration between two of the world’s most advanced centers of scientific research.

President Rivlin said: “The essence of science is rules. But maybe the most important rule is that collaboration and modern development can only happen together. As an Israeli, I know that you, Mr. Zuckerman, are one of the great people that has helped us create something that allows Israel to be appreciated all over the world for its education and responsibility. It is a great honor to welcome you at the President's Residence today.”

The Zuckerman STEM Leadership Program will give the highest-achieving American post-doctoral researchers and graduate students the ability to collaborate with leading researchers at Israel’s top research institutions – the Hebrew University of Jerusalem; the Technion-Israel Institute of Technology; Tel Aviv University; and the Weizmann Institute of Science – which are among the world’s most advanced.

Mr. Zuckerman said: "I was a guest in this country many times and have been fascinated and always moved by the many achievements of Israel. This is a society that knows how to develop and created a state that is absolutely a miracle. I have always admired what the Israelis could achieve in the country that is not rich in natural resources but rich in human resources. It is not oil, not gold or silver, but people who are willing to work hard and sometimes fight hard and I'm an advocate of Israel. I am deeply honored to be here.”

Mr. Zuckerman, Eric J. Gertler and James S. Gertler, Zuckerman Institute Trustees, Prof. Menahem Ben-Sasson, President of the Hebrew University of Jerusalem, Prof. Joseph Klafter, President, Tel Aviv University, Prof. Peretz Lavie, President, Technion-Israel Institute of Technology and Prof. Daniel Zajfman, President, Weizmann Institute of Science were in attendance along with a number of Zuckerman Scholars.

Prof. Menahem Ben-Sasson, President of The Hebrew University of Jerusalem, said: "The Zuckerman STEM initiative will strengthen connections between the academic communities of North America and Israel, and enrich the science and knowledge emerging from both regions for the benefit of people everywhere. As a new generation of scientists begin their careers, this initiative will allow them to develop roots in the best institutions in both regions, and to serve as catalysts for collaboration going forward.

By providing American graduate students and post-doctoral researchers with exposure to Israel’s renowned cutting-edge research and startup culture, the Zuckerman STEM Leadership Program will raise a generation of academic, scientific and industry leaders in the United States infused with a unique spirit of entrepreneurship and innovation.

Prof. Peretz Lavie, President of Technion - Israel Institute of Technology, said: "Today, Israel is in the front-line of scientific research and Israeli universities are at a stage where they are attracting post-doctoral students from around the world, creating networks and fellowships. The power of this $100 million donation will help create coherent scientific endeavors.  Four leading universities working together is absolutely unprecedented.”

The program will simultaneously bolster Israeli research institutions as world-leading centers for innovative research by providing Israeli institutions access to large-scale funding needed to develop top-tier research labs, projects, and programs.

Prof. Joseph Klafter, President of Tel Aviv University,  said: "Through the Zuckerman STEM Leadership Program, creativity will soar, discovery will soar, and the American-Israeli cooperation will soar farther than ever. We are deeply grateful for this vote of confidence in Israel by Mort Zuckerman."

The Zuckerman STEM Leadership Program will, over time, help strengthen the US-Israel partnership as Zuckerman Scholars return to the United States after building long-lasting relationships based in mutual collaboration. Israeli academic leaders returning to research institutions in Israel will similarly advance the overarching collaborative effort in science between the two nations as they continue to build bridges with their American colleagues.

Prof. Daniel Zajfman, President of the Weizmann Institute of Science, said: “The Zuckerman program aims at supporting the collaboration of the best minds between Israel and North America. This is one of the better ways to make a major impact in the world of STEM and an efficient way to support the world of science and technology. I can already imagine, in 10 years, the room full of Zuckerman fellows who have gone through this program, the impact of their work in the various Israeli and North America research programs, and the incredible network which will be created among these people."

The first cohort of 14 Zuckerman Scholars began with the 2016–2017 academic year. In the next twenty years alone, the program intends to provide over $100 million in scholarships and related educational activities that will benefit not only the participating scholars and universities, but the public as well.

Mortimer B. Zuckerman honored for $100 Million STEM Initiative
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Study of Israelis and Palestinians Calls for Rethinking How HDL Protects Against Coronary Heart Disease

03/08/2016

Small and medium sized HDL particles were more closely associated than HDL-C with protection against coronary atherosclerosis in a Jerusalem study

The idea that plasma high-density lipoprotein cholesterol (HDL-C) is protective against coronary heart disease has been part of medical conventional wisdom for five decades. HDL-C has traditionally been considered the most important component of so-called "good cholesterol" HDL. However, drug trials that increased HDL-C have failed to support a causal role for the amount of cholesterol carried in HDL in reducing the risk of coronary heart disease.

With advances in the separation of lipoproteins by size and functionality, research has intensified to identify HDL measures that may be better predictors of coronary heart disease than the traditional HDL-C.  Recent evidence suggests that small, dense, protein-rich particles in HDL may be more atheroprotective than large, buoyant cholesterol-rich particles.

To explore this further, 274 Arabs and 230 Jews residing in Jerusalem were recruited for a new study by researchers at the Braun School of Public Health in the Hebrew University of Jerusalem’s Faculty of Medicine. This work, led by Prof. Jeremy Kark of the Hebrew University-Hadassah Braun School of Public Health and Community Medicine, was undertaken by Dr. Chobufo Ditah, a physician from Cameroon, as his thesis for the Braun School’s International Masters of Public Health (IMPH) program. 

(Dr. Ditah, who received the Faculty of Medicine's award of excellence for his MSc thesis and graduated Magna Cum Laude from the IMPH  program, credits the Pears Foundation of Britain for enabling him to study at the Hebrew University. The IMPH program is made possible by donors who provide full scholarships to students from low-income countries, with the Pears Foundation endowing the largest number of scholarships and underpinning the associated alumni network. Dr. Ditah currently serves as a Medical Referent with the humanitarian NGO Doctors Without Borders (MSF), overseeing the implementation, evaluation and reorientation of medical interventions in host countries.)

The researchers used Nuclear Magnetic Resonance (NMR) spectroscopy to identify the numbers and sizes of plasma HDL particles, and helical CT-scanning to identify calcification in their coronary arteries, reflecting the overall burden of coronary atherosclerosis. With these data in hand, they looked for associations between the concentrations and sizes of different HDL particles, and coronary artery calcification.

Their findings, published in the prestigious journal Atherosclerosis, showed a statistically significant inverse association of both the number of HDL particles (HDL-P) and the concentration of small and medium-sized HDL particles (MS-HDL-P) with coronary artery calcification, after adjusting for age, statin use, smoking, and other factors. There was no association between large HDL-P and coronary artery calcification in either population group. The association with HDL-C was weaker and inconsistent between men and women.

"Our findings indicate that HDL-P and MS-HDL-P are better independent markers of coronary artery disease, as reflected by coronary artery calcification, than HDL-C, at least in this bi-ethnic population of Israelis and Palestinians," said Dr. Chobufo Ditah.

"With a better understanding of HDL's complexity and a better ability to measure its components, it is now possible to move past HDL-C to more refined measures that better reflect HDL's role in coronary heart disease risk. Based on the accumulating evidence, incorporation of MS-HDL-P or HDL-P into the routine prediction of coronary heart disease risk should be considered," said Prof. Jeremy Kark.

"These findings support previous reports, based on studies in other population groups, suggesting that small dense HDL particles are protectively associated with risk of coronary heart disease. The consistency of this finding in a new population of urban Arabs and Jews, using different disease outcomes and different separation methods, add more strength to those findings," added Dr. Ditah.

Participants in this research are affiliated with the following institutions: Hebrew University-Hadassah Braun School of Public Health and Community Medicine; Hebrew University Faculty of Medicine; Hadassah Medical Center, Ein Kerem, Jerusalem; Mankon Sub-Divisional Hospital, Cameroon; LipoScience, Laboratory Corporation of America Holdings, USA.

The Hebrew University-Hadassah Braun School of Public Health and Community Medicine (link), in the Hebrew University’s Faculty of Medicine, is the first school of public health in Israel. Its world-renowned International Master’s in Public Health (IMPH) program (link) graduated its 40th class in 2015, featuring a diverse student body ranging from Cameroon to Kosovo, the United States to Jerusalem. The International MPH degree has been awarded to more than 800 graduates from 92 low-income countries in Africa, Asia, Latin America, Eastern Europe, as well as developed countries of North America and Western Europe. The comprehensive multi-disciplinary 12-month training experience prepares graduates to take up key positions as leaders and teachers of public health in their home countries, and to initiate and participate in the promotion and development of public health practices and develop capacity-building programs for training public health personnel.

The Hebrew University of Jerusalem is Israel’s leading academic and research institution, producing one-third of all civilian research in Israel. For more information, visit http://new.huji.ac.il/en.

FUNDING: This study was supported by research grants from the USAID Middle Eastern Regional Cooperation (MERC) Program (grant no TA-MOU-01-M21-002) and from D-CURE-Diabetes Care in Israel to Jeremy Kark.

CITATION: Small and medium sized HDL particles are protectively associated with coronary calcification in a cross-sectional population-based sample. Atherosclerosis, Volume 251, August 2016, Pages 124–131.  Chobufo Ditah, James Otvos, Hisham Nassar, Dorith Shaham, Ronit Sinnreich, Jeremy D. Kark. doi:10.1016/j.atherosclerosis.2016.06.010 http://www.sciencedirect.com/science/article/pii/S0021915016302556

Study of Israelis and Palestinians Calls for Rethinking How HDL Protects Against Coronary Heart Disease
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IMRIC Scientist Awarded for Work in Stem Cells & Regenerative Medicine

18/07/2016

Dr. Yosef Buganim is a young researcher at the Institute for Medical Research Israel-Canada (IMRIC), part of the Hebrew University’s Faculty of Medicine

Dr. Yosef Buganim, a research scientist at the Hebrew University of Jerusalem, has been honored by the American Association for the Advancement of Science (AAAS), the prestigious journals Science and Science Translational Medicine, and the Boyalife industrial research consortium, for his work in stem cells and regenerative medicine. (See Buganim’s essay in Science at http://science.sciencemag.org/content/352/6292/1401.full).

Dr. Buganim is a young researcher who recently joined the Department of Molecular Biology and Cancer Research at the Institute for Medical Research Israel-Canada (IMRIC, http://imric.org). Part of the Hebrew University’s Faculty of Medicine, IMRIC is one of the most innovative and multidisciplinary biomedical research organizations in the world.

Awarded for the first time this year, the Boyalife Science & Science Translational Medicine Award in Stem Cells & Regenerative Medicine honors researchers for outstanding contributions in stem cell research and regenerative medicine around the globe. AAAS, Science, and Science Translational Medicine joined efforts with Boyalife, an industrial-research consortium formed in Wuxi, China, in 2009, to sponsor the award.  Composed of prominent researchers, the judging panel was co-chaired by a Science and a Science Translational Medicine editor.

At his Hebrew University laboratory, Buganim uses somatic cell conversion models to identify and investigate the elements that facilitate safe and complete nuclear reprogramming. As a postdoctoral fellow at the Whitehead Institute for Biomedical Research at MIT, he used single-cell technologies and bioinformatic approaches to shed light on the molecular mechanisms that underlie the reprogramming of somatic cells to iPSCs.

Regenerative medicine is a developing field aimed at regenerating, replacing or engineering human cells, tissues or organs, to establish or restore normal function. Embryonic stem cells have enormous potential in this area because they can differentiate into all cell types in the human body. However, two significant obstacles prevent their immediate use in medicine: ethical issues related to terminating human embryos, and rejection of foreign cells by a patient's immune system.

In 2006, Japanese researchers discovered that it is possible to reprogram adult cells and return them to their embryonic stage, creating functional embryonic stem-like cells. These cells are known as induced pluripotent stem cells (iPSCs), and constitute a solution to these two obstacles. In addition, these cells provide a good basis for modeling diseases and finding medical solutions, because they can be reproduced from different patients and different diseases.

Despite these cells’ enormous potential, their quality is still not sufficient to be used in clinical practice, and there is a need to find the best protocol that will enable production of high-quality iPSCs that will not endanger patients.

Dr. Buganim’s laboratory has made two major breakthroughs in this area, representing a major step forward in the field of regenerative medicine and transplantation.

Project A: To improve the quality of embryonic stem cells, Dr. Buganim and colleagues conducted bioinformatics analyses which pointed to four new key genes capable of creating iPSCs from skin cells, of superior quality to stem cells in current use. These cells produced in his laboratory (in this case mouse cells) are able to clone a whole mouse at a much higher percentage (80%) than other iPSCs (30%). This test is the most important one determine the quality of the cells.

Project B: Many women suffer recurrent miscarriages and abnormal development of the placenta, which causes fetal growth restriction and in some cases produces children with mental retardation. Dr. Buganim’s lab found the key genes of the placenta stem cells and by expressing them in surplus in skin cells, created placental iPSCs. These cells looked and behaved like natural placental stem cells. Various tests showed that these cells have cell-generating capability in a Petri dish and inside a placenta that develops following a transplant. These cells have potential for use in regenerative medicine in cases of problematic placental functioning. The success of this project may enable women with placenta problems to give birth to healthy children and rescue pregnancies at risk of dysfunctional placenta. (See details at http://new.huji.ac.il/en/article/27928.)

Forward-looking: Alongside creating specific cell types (e.g. nerve cells in patients with Parkinson's disease, ALS and Alzheimer) from a patient’s skin cells, a potential future use of iPSCs is the creation of whole organs (such as heart, liver or kidney) in a suitable animal model using cells taken from the patient.

Citation: Science, Vol. 352, Issue 6292, pp. 1401, DOI: 10.1126/science.aag1215 (link: http://science.sciencemag.org/content/352/6292/1401.full)

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Boyalife Group, previously known as the International Consortium of Stem Cell Research (INCOSC), was founded in July 2009 in Wuxi, China. In July 2015, Boyalife became the world’s first Stem Cell Bank accredited by AABB standard of Somatic Cell. Through subsidiaries, the company is also engaged in regenerative medicine, genomics, animal cloning, innovative drug discovery and disease modeling.

The American Association for the Advancement of Science (AAAS) is the world's largest general scientific society, and publisher of the journals Science, Science Translational Medicine, Science Signaling and Science Advances. The non-profit AAAS -- www.aaas.org -- is open to all and fulfills its mission to "advance science and serve society" through initiatives in science policy, international programs, science education, and more.

The Institute for Medical Research-Israel Canada (IMRIC), in the Hebrew University of Jerusalem's Faculty of Medicine, is one of the most innovative biomedical research organizations in Israel and worldwide. IMRIC brings together brilliant scientific minds to find solutions to the world's most serious medical problems, through a multidisciplinary approach to biomedical research. More information at http://imric.org.

The Hebrew University of Jerusalem is Israel’s leading academic and research institution, producing one-third of all civilian research in Israel. For more information, visit http://new.huji.ac.il/en.

IMRIC Scientist Awarded for Work in Stem Cells & Regenerative Medicine
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Single Dose of Novel Peptide Protects Cognitive Function After Mild Traumatic Brain Injury (mTBI)

11/07/2016

New molecules, developed by Hebrew University of Jerusalem scientists, reduce inflammation, cell death and cognitive impairments following traumatic brain injury in mice

Whether at school, in car accidents, on the sports field or the battlefield, mild traumatic brain injury (mTBI) is a common part of our lives. It is especially frequent among children, athletes, and the elderly. Now, scientists at the Hebrew University of Jerusalem have shown that a single dose of a new molecule they developed can effectively protect the brain from inflammation, cell death, and cognitive impairments that often follow a mild traumatic brain injury.

Because it lacks visible external signs or objective structural brain damage, mTBI is an under-diagnosed injury. Yet it is often accompanied by long-lasting cognitive, behavioral and emotional difficulties associated with biochemical and cellular changes.  While most symptoms of mTBI are substantially resolved within days or weeks of the injury, up to 50% of mTBI patients experience symptoms at one-year post-injury. These can include psychological symptoms, subjective cognitive impairments, and somatic (physical) complaints.

These changes could result from an increase in glutamate levels, oxidative stress, opening of the blood-brain-barrier, and in particular inflammatory activity followed by cell death (apoptosis).  

Currently there is no effective treatment for patients with mTBI. 

“It is widely known that external or internal injury strongly activates the inflammatory response and leads to cell death (apoptosis) through the MAPK pathways, which are involved in the cellular responses that lead to inflammation in brain cells,” explains Prof. Daphne Atlas, from the Department of Biological Chemistry in the Alexander Silberman Institute of Life Sciences at the Hebrew University of Jerusalem. “Therefore, for reversing the effects of mTBI it is essential to calm the inflammatory pathways.”

At her laboratory in Jerusalem, Prof. Atlas has developed new molecules derived from the active site of Trx1, called thioredoxin-mimetic peptides (TXM-peptides). Thioredoxin (Trx1) is a major protein that maintains the oxidation/reduction state of the cells. In its reduced form it is bound to another protein (ASK1), which is released upon oxidation of Trx1 and activates a chain of enzymatic reactions that lead to inflammation. 

The newly-synthesized thioredoxin-mimetic peptides (TXM-peptides) have been shown to protect cells from early death via the activation of inflammatory pathways. Comprising 3 or 4 amino acids, these peptides have dual activity: they mimic the antioxidant activity of Trx1, and simultaneously inhibit the activity of enzymes called MAPK within the inflammatory pathway, preventing inflammation and cell death.

TXM-CB3 was previously shown to effectively lower MAPK activity in animal models of asthma and in the brain of rat model of diabetes [Kim et al 2011; Bachnoff et al 2011; Cohen-Kutner et al 2013, 2014]. The peptides managed to cross the blood-brain barrier and improve the condition of brain cells by lowering the inflammatory processes.

In the current study, published in the peer-reviewed journal PLOS ONE, Prof. Atlas and colleagues explored the impact of TXM-peptides, TXM-CB3 and TXM-CB13 (DY70; provided by OneDay Biotech and Pharma Ltd), on preventing mTBI cognitive secondary injury.  The experiments were performed in collaboration with researchers at Tel Aviv University, Prof. Chagi Pick and Dr. Renana Baratz-Goldstein

Researchers induced cognitive impairments in anesthetized mice by a weight drop resulting in mild traumatic brain injury. The mice showed a decrease in spatial memory in the Y-maze test and a loss in visual learning ability in the novel object recognition test.  Lower learning ability was also detected 30 days post injury in the mTBI mice.

In these two independent tests, a single dose of either one of the TXM-peptides administered 60 minutes post-injury, at a 50 mg per kg of body weight, significantly improved the decline in cognitive performance and learning ability at 7 and 30 days post injury. In addition, the two TXM-peptides were found highly effective at inhibiting the MAPK activity in neuronal cells grown in tissue culture.

“This research demonstrates the potential for TXM-peptides to significantly reduce cognitive impairment after mild traumatic brain injury,” said Prof. Atlas. “Further studies are required to establish and examine the potential of a single dose of TXM-peptide in preventing damage if administered even one hour after brain trauma in human scenarios — for example, in chronic traumatic encephalopathy observed in American football players, which result from multiple concussions and other types of blows to the head.

"Another advantage to using peptides is in significantly reducing the risk of causing toxic effects, because they consist of amino acids which are the natural building blocks comprising cell proteins, in contrast to the use of drugs that are not natural.  So TXM-CB3 and TXM-CB13 are promising treatment candidates to prevent secondary damage that affect brain function,” said Prof. Atlas.

About The Hebrew University of Jerusalem

The Hebrew University of Jerusalem is Israel’s leading university and premier research institution. Founded in 1918 by such innovative thinkers as Albert Einstein, Martin Buber and Sigmund Freud, the Hebrew University is a pluralistic institution where science and knowledge are advanced for the benefit of humankind. The Hebrew University is ranked internationally among the top 100 universities in the world, and first among Israeli universities. Serving 23,500 students from 85 countries, the Hebrew University produces a third of Israel’s civilian research, and its faculty are at the forefront of the international academic and scientific communities. For more information, please visit http://new.huji.ac.il/en.

FUNDING: This research was supported by the Ari and Regine Aprijaskis Fund at Tel-Aviv University, and by The H.L Lauterbach Fund (Hebrew University) to Daphne Atlas.

CITATION: Baratz-Goldstein, R., Deselms, H., Heim, L. R., Khomski, L., Hoffer, B. J., Atlas, D., & Pick, C. G. (2016). Thioredoxin-Mimetic-Peptides Protect Cognitive Function after Mild Traumatic Brain Injury (mTBI). PLoS ONE11(6), e0157064. http://doi.org/10.1371/journal.pone.0157064 (Link:  http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0157064)

Single Dose of Novel Peptide Protects Cognitive Function After Mild Traumatic Brain Injury (mTBI)
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Bees Diversify Diet to Take the Sting Out of Nutritional Deficiencies

13/04/2016
New research shows that honey bees forage for a diet that balances their colony’s specific nutritional deficits

While pesticides and pathogens pose clear threats to honey bee health, the need of bee colonies for balanced nutrition is gaining increasing appreciation. As colonies are kept in agricultural areas for crop pollination, they may encounter nutritional deficits when foraging predominantly on one pollen source. In California almond orchards for instance, 1.6 million colonies are kept every year, despite the risk of low floral diversity, which can reduce the life expectancy of bees.

In light of the challenge that agricultural intensification poses for pollinator habitats, Dr. Harmen Hendriksma and Prof. Sharoni Shafir from the Hebrew University of Jerusalem report that honey bee colonies are astoundingly resilient to nutritional stress. In new research reported in the journal Behavioral Ecology and Sociobiology, they found that bees can shift their foraging effort towards resources that complement nutritional deficits.

The research was conducted at the B. Triwaks Bee Research Center, Department of Entomology, The Robert H. Smith Faculty of Agriculture, Food and Environment, at the Hebrew University of Jerusalem.

In their experiment, eight honey bee colonies were kept in screened enclosures and fed pollen substitute diets that were deficient in particular essential amino acids. Subsequently, the bees were tested for their dietary choice, between the same diet previously fed, a different diet that was similarly deficient, or a diet that complemented the deficiency. The foragers preferred the complementary diet over the same or similar diets.

This result indicates that honey bee colonies not only attempt to diversify their diet, but that they bias their foraging effort towards a diet that specifically balances nutritional deficits of the colony. How bees perceive and evaluate nutrient composition needs further elucidation. This new-found ability of honey bees to counter deficient nutrition contributes to mechanisms that social insects use to sustain homeostasis at the colony level.

“This research indicates that honey bee colonies strive to balance their nutrition if appropriate floral resources are available. Bee colonies can benefit by this type of resilience when food options are sparse, for instance at certain sites or in seasons of dearth. Since alternative floral resources can help bees to balance their nutritional needs, this should serve as an incentive for everyone to plant flowers, wherever and whenever they can,” said Dr. Harmen Hendriksma.

“Our research with bees continues to reveal their remarkable abilities. Honey bee colonies must maintain a balanced diet for optimal health, and bee foragers seem to have evolved the sophisticated ability to bias their efforts towards finding food that balances the colony’s nutritional deficiencies. In so doing they remind us that in nutrition, as in many other things, maintaining the proper balance is key,” said Prof. Sharoni Shafir.

The Hebrew University of Jerusalem is Israel’s leading academic and research institution, producing one-third of all civilian research in Israel. For more information, visit http://new.huji.ac.il/en.

VIDEO 1: https://youtu.be/WqbDrAJjRkQ - Honey bee workers in this video hover over feeding dishes with different diets. While flying, bees may distinguish differences by sight and by scent. Here, bees were given a choice between 34 different diets. Notably, protein content was found least explanatory for their choice behavior, while their preference was best explained by the foods color intensity and caloric contents (please see the supplements to the paper).  (Video credit: Harmen P Hendriksma)

VIDEO 2: https://youtu.be/YyTKbRd2uWQ - Honey bee workers in this video are collecting diet from feeding dishes. Bees touch the diet with their antennas, their feet, and mouth parts. Bees have receptors on these body parts, and it is likely that bees are probing the diet for taste, smell and texture. (Video credit: Harmen P Hendriksma)

FUNDING: The research was funded jointly by a grant from the BBSRC, NERC, the Wellcome Trust, Defra, and the Scottish Government under the Insect Pollinators Initiative (grant no: BB/I000968/1), and with partial support from the Orion Foundation.

REFERENCE: Harmen P. Hendriksma , Sharoni Shafir. Honey bee foragers balance colony nutritional deficiencies. Behavioral Ecology and Sociobiology. April 2016, Volume 70, Issue 4, pp 509-517.  doi:10.1007/s00265-016-2067-5 (link: http://link.springer.com/article/10.1007/s00265-016-2067-5)

Bees Diversify Diet to Take the Sting Out of Nutritional Deficiencies
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