Month: April 2021

Substantial tissue loss can be the result from different causes, including cancer, injury, and infection. Reconstructive surgery attempts to mitigate the damage. Currently, the clinical “gold standard” in the field of reconstructive surgery is the autograft, which entails harvesting tissue from one part of the patient’s body, and transferring it to the damaged site. For example, to reconstruct the lower jaw, surgeons may harvest a portion of the fibula bone, together with the soft tissue and blood vessels around it, from the patient’s leg. The soft tissue and blood vessels are necessary for the bone to survive in its new location.

As one might imagine, there are significant disadvantages to taking a large chunk out of one’s body, such as considerable pain or all the usual complications associated with a surgery at the donor site. Scientists are therefore looking for alternatives to tissue harvest and moving towards tissue engineering. Although some progress has been made in the field, there are still major challenges to overcome in the search for tissue replacements. The Holy Grail for the scientists is de novo tissue generation. Instead of taking tissues from one part of the body to implant in another, new tissues for implantation would be grown in a lab.

That is where Professor Shulamit Levenberg and her team come in. In the Faculty of Biomedical Engineering at the Technion, the focus of her tissue regeneration lab has been on the formation of complex blood vessel networks in lab-grown tissues. Recently, her team created vascularized soft tissues for implantation using stem cells derived from the dental pulp, that is the soft tissue inside the tooth, together with capillary forming (endothelial) cells. The addition of the dental pulp stem cells promoted the generation of the blood vessels, eventually leading to enhanced tissue remodeling and repair. The new methodology was then used to repair a bone defect in rats, leading to a complete recovery.

. 

As previously mentioned, bone implanted as part of reconstructive surgery would need soft tissues to support it and blood vessels to feed it. In a recent study conducted in Prof. Levenberg’s lab, Dr. Idan Redenski and his colleagues were able to tackle the issue. In findings recently published in Advanced Functional Materials (link), the team put together their own vascularized tissue technology with biological bone implants developed at Columbia University by Professor Gordana Vunjak-Novakovic to create a de novo tissue flap containing live bone supported by vascularized soft tissue. This took the concept of implantable bone tissue to a whole different level.

That, however, was only the first stage. Having shown that a mixed tissue flap can be grown, the team proceeded to use the new methodology to repair a bone defect in rats, using a two-step approach. First, an engineered soft tissue flap was implanted. Once it was integrated into the body of the rat, the engineered flap was exposed in a second surgery and used to repair a bone defect, while being supported by major blood vessels next to the defect site. The decellularized bone was exposed and inserted to correct the existing defect while the engineered tissue flap supported it. The results were a complete success: the soft tissue with the blood vessels supporting and feeding the bone led to bridging of the bony defect, with the rat’s cells growing in and replenishing the implant. It was, in fact, a complete recovery, better than anything reconstructive surgery can achieve, and not based patient tissue harvest.

Returning to the concept of a jaw implant, one can hope that one day, based on the methods developed by Prof. Levenberg, Dr. Redenski, and the rest of the team, it will be possible for the patient to receive a lab-grown bone perfectly matching the shape of their face, surrounded by lab-grown soft tissues based on their own cells cultivated on 3-dimensional biomaterials. No major damage to other parts of the patient’s body would be necessary.

After finishing his Ph.D., Dr. Redenski will begin a residency in oral and maxillofacial surgery at the Galilee Medical Centre, where he plans to continue his research with the hope of taking the methods developed in Prof. Levenberg’s lab and implementing them in the clinic.

The following people took part in this research: Dr. Idan Redenski, Shaowei Guo, Majd Machour, Ariel Szklanny, Shira Landau, Ben Kaplan, Roberta I. Lock, Yankel Gabet, Dana Egozi, Gordana Vunjak-Novakovic, and Prof. Shulamit Levenberg. Special thanks go to Bruker-Skyscan for their assistance with the microCT studies, allowing non-invasive and precise observation of the healing process.

For the full article in Advanced Functional Materials click here

At just 26 years of age, Lina Maudlej has already accumulated a very impressive list of projects and achievements including her volunteering activities. In recognition of this, she was recently awarded the Shosh Berlinsky Sheinfeld Award for social involvement in the community. The 10,000 ILS prize is intended to encourage and appreciate students who donate their time and skills to the community.

Ms. Maudlej was born in Kafr Qara in Wadi Ara and attended Al-Qasemi High School in Baqa al-Gharbiyye. “I didn’t have a background in computing at home, but science always interested me – and in high school, I was particularly passionate about physics and mathematics. Since I knew that the Technion was the place for these subjects, I signed up and was accepted.”

Ms. Maudlej began her studies at The Andrew and Erna Viterbi Faculty of Electrical Engineering, and after taking several courses at the Henry and Marilyn Taub Faculty of Computer Science, she joined the combined track of the two faculties – computer engineering. After finishing her undergraduate degree, she went on to pursue her master’s, which she is hoping to complete this year under the guidance of Professor Mark Silberstein. Her research, conducted in the Accelerated Systems Laboratory (ACSL), deals with accelerator management in cloud computation systems. Most of the work is focused on building a new operating system that will run computational accelerators such as GPUs while achieving high performance and maximum efficiency by using network accelerators.

“My supervisor always saw great potential in me,” said Ms. Maudlej, “both in my research and in my volunteer work. That is why he was so supportive and helped direct me to places where I could develop myself in unexpected ways. I know that being challenged is the right place for me and working with Prof. Silberstein is the right choice. Every day you learn something new. Science never ends, and the challenge is what makes it interesting.” 

Throughout her undergraduate and graduate years, she hasn’t stopped for a moment. In the final stages of her undergraduate degree she worked at Intel, won an award from Amdocs and led projects in the IT course, the “Internet of Things.” On top of this, she continued with her many and varied volunteer activities, which included expanding Wikipedia into Arabic for math, scientific, and technological subjects; participation in the Landa Project, supporting Arab students; and involvement in the Hasoub NGO, promoting technology and innovation in the Arab sector.

Toward the end of her undergraduate degree, Lina became the facilitator in charge of the “Internet of Things” course in the Computer Science Software Development Center (ICST) led by Itai Dabran, and within this framework mentored many young students. She also led systems development projects for the Technion Social Hub together with various organizations, including the Levchash association. The various projects carried out through the hub helped nonprofits by developing programs to support those organizations in need and matching them with volunteers and donors. In this capacity, she dealt with a reduction in food waste in Israel, supporting needy populations, and recycling.

When asked if volunteering gets in the way of her studies, Ms. Maudlej replied, “On the contrary, volunteering helps studies and increases motivation to learn, and vice versa.” And what’s next? “On one hand, I really like academia so going on to do a Ph.D. is a definite possibility. On the other hand, my research is already very practical and is carried out in cooperation with industry, so finding a job outside academia is also possible. The Technion teaches us to think, and this is an important and very effective tool wherever you are – either here at the Technion or in industry.”

 

Researchers from the Technion and the University of Zurich: Contrary to the prevailing assumption, the brain of the first migrants from Africa to Asia 1.8 million years ago was not a modern brain

Researchers from the Technion and the University of Zurich have published a dramatic discovery in Science Magazine about the characteristics of the brain of the first human migrants from Africa to Europe. To date, the accepted theory was that although these individuals – who migrated from Africa to the Caucasus about 1.8 million years ago – had small brains, these small brains had a modern structure similar to that of the human brain today. The present study proves otherwise: their brains were more ape-like than human-like.

Dr. Assaf Marom, head of the Anatomy and Human Evolution Laboratory at the Rappaport Faculty of Medicine at the Technion, participated in the study as a postdoctoral researcher for the lead authors of the article, Professor Marcia Ponce de León and Professor Christoph Zollikofer of the Anthropological Institute at the University of Zurich.

According to Dr. Marom, “Until now, it was assumed that the brains of the first migrants from Africa to Europe, although smaller than ours, were anatomically more similar to the brains of humans today than to the brain of a chimpanzee. The present research refutes this assumption; not only were their brains smaller than ours, but they were also more ape-like than human-like. Analysis of the structure of the braincase, particularly in the frontal lobe area, shows that it more resembled the frontal lobe of a primate than the modern human frontal lobe. The human frontal lobe houses neuroanatomical centers to which we attribute human higher functions: planning and decision making, speech, use of tools and instruments, complex social interaction and others.”

The discovery also refutes the belief that the early populations of the human species left Africa as a result of that same evolution into the modern brain structure; according to the new findings, they succeeded in migrating out of Africa and in surviving the journey despite the absence of such a brain. Dr. Marom emphasizes that the term “primitive brain” is not derogatory; those early humans possessed numerous cognitive skills that enabled them to defend themselves, lead cooperative social lives and make basic use of certain tools. “We explain these evolutionary processes as ‘coevolution’ – this is evidence that the development of those tools also played a part in the evolution of the human brain – not only as a result of cognitive skills, but also as their cause.”

Since brains do not fossilize, the study of the brains of ancient species is a tough challenge; consequently, we are forced to rely on indirect evidence such as skull remnants. In the present research, the brain was reconstructed using advanced, high-resolution computed tomography performed in a synchrotron – a particle accelerator, in Grenoble, France. Scans were performed on five skulls discovered in the prior decade in the ancient Georgian village of Dmanisi, the oldest evidence of human presence outside Africa, dated around 1.8 million years ago.

Based on the scans, Dr. Marom reconstructed an endocast, a cast made of the inside of a cranial cavity, shedding light on human neuroanatomy, i.e. the structure of the brain itself. CT scans produce horizontal, or axial, images (slices) of the brain, and Dr. Marom explains that meticulous work was required while reviewing the slices in order to remodel the three-dimensional structure of the endocast. The process yielded a reconstruction of the brain, including the convolutions and furrows of the cerebral cortex, and even its vascular network.

“Man became bipedal around 2.5 million years ago, but his brain was small and primitive. One of the important research questions in human evolution deals with determining the date of the neuroanatomical changes that transformed the brain from ape-like to man-like. Again, until now, it was commonly assumed that these changes occurred in Africa before the first migration to Europe, but we demonstrated that this assumption is incorrect, and those migrants of 1.8 million years ago had primitive brains.”

The conclusion drawn by the researchers is that the modern brain evolved in a later period – 1.5 to 1.7 million years ago, and at that time, more migrations from Africa to Europe had taken place. In its next study, the research team intends to explore the possibility that the “new” migrants with their modern brains encountered the descendants of the ancient migrants and maintained some sort of interaction with them.

Dr. Assaf Marom (M.D., Ph.D.) joined the staff of the Faculty of Medicine after completing his medical studies and doctorate in physical anthropology at Tel Aviv University, and his post-doctorate at the Anthropological Institute at the University of Zurich. He is head of the Anatomy and Human Evolution Laboratory, which integrates imaging and calculation methods to build models allowing for the discovery of when, why and how human beings came to be. Dr. Marom teaches anatomy at the Faculty of Medicine and the Faculty of Biomedical Engineering at the Technion.

For the article: https://science.sciencemag.org/content/372/6538/165

 

 

New discoveries by a team of researchers from Technion, BGU, and HZB, are advancing the understanding of semiconductors, for the purpose of harvesting solar energy

Photovoltaic solar cells are devices that convert sunlight into electricity. Sunlight, however, is available only several hours a day. In order to be used at night, or on cloudy days, energy must be stored to ensure a stable power supply. One approach for doing so is to charge rechargeable batteries during the day, using solar power, and to discharge them to the grid during the night. This requires large-scale battery storage that increases the cost of solar power and is only effective for short-term storage. Long-term seasonal storage requires other solutions.

Another approach, which is the subject of studies by Professor Avner Rothschild from the Technion – Institute of Technology and his research group, is to use photoelectrochemical cells to convert sunlight not into electricity, but into hydrogen fuel produced by splitting water molecules (H2O) into hydrogen (H2) and oxygen (O2). The stored hydrogen can be used later for producing electricity, or put to other uses such as heating, fueling fuel-cell electric vehicles, and various industrial processes such as steelmaking, petrochemical refining, and ammonia production. 

At the heart of both photovoltaic and photoelectrochemical solar cells is a semiconductor photoabsorber – a material capable of absorbing photons and generating free charge carriers (electrons and holes) that contribute to the photocurrent. But where commercial solar cells use silicon for that purpose, photoelectrochemical cells must rely on other materials that display greater compatibility to the conditions in which the cell must operate, such as stability in aqueous electrolytes. A promising material for that purpose is hematite, an abundant form of iron oxide whose chemical composition is similar to that of rust. Until now, though, hematite has been frustrating scientists: despite half a decade of research, scientists have been able to obtain from it less than 50% of the solar energy conversion efficiency that theory predicts. Prof. Rothschild’s group now shows in a paper in Nature Materials why this is the case and presents a novel way of assessing the actual efficiency limit that might be obtained from hematite and other semiconductors.

The group postulated that the efficiency loss in hematite is not caused solely from charge carrier recombination, a well-known effect that can be mitigated by nanostructuring and light trapping techniques but occurs also due to internal light–matter interaction effects that cannot be mitigated by these approaches. According to their hypothesis, a portion of the electrons excited by absorbed photons are excited into electronic states that cannot move freely within the material. The absorbed photons that give rise to these localized electronic transitions are thus “wasted” without contributing to the photocurrent. 

Using an ultrathin (7 nm) hematite film, the group was able to measure the effect in correlation to wavelength, extracting the so-called wavelength dependent photogeneration yield spectrum. In collaboration with the research group of Professor Roel van de Krol from the Institute for Solar Fuels in Helmholtz-Zentrum Berlin, they measured a similar spectral response of photogenerated charge carriers by another, microwave-based technique. Obtaining similar results by the two different methods serves as a verification of the method and demonstrates that the photogeneration yield is an overlooked, yet fundamental limitation responsible for the underperformance of hematite photoelectrodes for solar energy conversion and storage.

The group’s novel method will allow the characterization of other materials in the same way they characterized hematite, providing information on the limitations of different materials and giving access to information about light-matter interaction in correlated electron materials with non-trivial opto-electronic properties. This will open the way to more efficient construction of photoelectrochemical cells, giving access to renewable energy and green hydrogen fuel.

The following took part in the research: Dr. Daniel Grave, a scientist at the Department of Materials Engineering at Ben Gurion University of the Negev; Dr. David Ellis, Yifat Piekner, Dr. Hen Dotan, Dr. Asaf Kay, and Prof. Avner Rothschild from the Department of Materials Science and Engineering and the Grand Technion Energy Program at the Technion – Israel Institute of Technology; as well as Dr. Moritz Kölbach, Patrick Schnell, Dr. Fatwa Abdi, Dr. Dennis Friedrich, and Prof. Roel van de Krol from the Institute for Solar Fuels at the Helmholtz-Zentrum Berlin. The research leading to these results received funding from the PAT Center of Research Excellence supported by the Israel Science Foundation.

Click here for the paper in Nature Materials

Agricultural irrigation accounts for 80 percent of water usage in the United States. In Israel, the number is just under 60 percent. With water being a finite resource, the use of recycled water for irrigation is a significant contributor to water conservation. As part of the purification process necessary in order to safely use recycled water for irrigation, excess sodium should be removed, but some minerals, such as calcium and magnesium, should be retained.

A high ratio of sodium to calcium and magnesium, also known as Sodium Absorption Ratio, adversely affects soil permeability, negatively impacts water infiltration rate, and damages crops. Over time it can cause the salinization of the soil, and such damage can be hard to reverse. Modern methods of water purification are either non-selective, removing wanted minerals and unwanted salts alike and requiring subsequent remineralization of the water; or expensive and not tunable (i.e., they cannot be dynamically adjusted for different feedwater inputs or for changing effluent requirements).

Capacitive deionization is a novel water treatment technology that aims to improve precisely on this non-selectivity. Capacitive deionization uses two electrodes, which are often made from activated carbon, an inexpensive and widely available material. Applying electric charge to the electrodes causes salts and minerals in the feedwater to migrate into the electrodes and collect in nanopores on them – essentially in microscopic content-specific pockets. When these “pockets” are full, reversing the charge empties them out, and the electrode is ready for use again. The problem with this method is that the electrodes wear out quickly.

A breakthrough was recently achieved by Professor Matthew Suss of the Technion Faculty of Mechanical Engineering and Wolfson Department of Chemical Engineering, and his team (Ph.D. students Eric Guyes and Amit Shocron, and master’s student Yinke Chen), in collaboration with Professor Charles Diesendruck of the Technion’s Schulich Faculty of Chemistry, whose main interests are water desalination and energy conservation.

In the team’s system, water flows through two porous electrodes. By sulfonating one of the electrodes – that is, executing a chemical reaction that is cheap and easy to perform – the team was able to produce a capacitive deionization cell that proved effective in reducing the Sodium Absorption Ratio of the feedwater, giving significantly better results than cells with electrodes that were not similarly treated. The electrode was also much more stable than what has previously been described. The team ran 1000 cycles of water treatment through it, without the electrode showing significant deterioration – a record cycle life for a cell of this type. 

The process was energetically efficient, and the efficiency can be improved further using already existing methods. The system is also easily tuneable. By changing the voltage and the charging time of the electrodes, different results can be obtained, making the method applicable to various uses, including irrigation and more. The findings could lead to a number of practical applications, since the team managed to improve on all aspects of water purification systems that continue to pose a challenge.

Click here for the paper in Clean Water

 

 

EuroTech Innovation Day: One Day, Three Hackathons

The Technion’s “t-day” will return on April 28th. This year, it will be an online event, in conjunction with the EuroTech Innovation Day.

On April 28th the Technion will host its annual “t-day”, this year as an online event. t-day – a celebration of entrepreneurship and innovation – focuses on providing Technion students with a unique exposure to advanced tools and methods that can boost entrepreneurship, innovation, creativity, career development and broader issues related to social justice.

As part of the event, t-hub, the Technion Entrepreneurship and Innovation Center, will also host the EuroTech Universities Alliance’s Innovation Day, and, jointly with the Biomedical Engineering Faculty – the EuroTech Biomedical Engineering Hackathon. The EuroTech Universities Alliance is a strategic partnership of leading European universities of science and technology. Its members, alongside the Technion, include some of the leading European technological universities. The EuroTech events will be conducted in English, while the rest of the t-day events will be in Hebrew.

The Technion invites students, alumni, faculty, and staff to participate in this fascinating day. Some of the day’s noteworthy events include:

• Opening lecture – “success in a changing world” – by Prof. Yoram Yovell
• Closing lecture – “creativity in life and work” – by Dr. Eyal Doron
• FinTech hackathon, held with MALAM TEAM and the Bank of Jerusalem
• “Technion Dresses Smart” hackathon, together with the Technion Social Hub
• BizTEC 2021 opening event
• Job interview simulator

The Technion Innovation Day is a joint initiative of t-hub, the Dean of Students Office, the Technion Student Association, the Technion’s DRIVE Accelerator, and the Technion Alumni Association.

Click here for agenda and registration.

 

“What sets us apart from other universities is that there is no other whose commitment to their country plays such a central role. Our founders perceived the Technion as the Jewish people’s university, a role we are proud to fulfill to this very day.” A special message from Technion President, Professor Uri Sivan, for Yom HaZikaron (Remembrance Day) and Yom Ha’Atzmaut (Independence Day).

Dear Friends,

This coming Thursday, we celebrate Yom Ha’Atzmaut (Independence Day), marking the 73rd anniversary of the establishment of the State of Israel. Yom Ha’Atzmaut is preceded by Yom HaZikaron, the Day of Remembrance for all those who gave their lives in the defense of Israel. I cannot think of any other country that places side by side a solemn day of memory with a day of total celebration, acting as a sober reminder that Independence comes at a price.

The two loud ear-piercing sirens that ring through Israel’s streets during Yom HaZikaron bring the entire country to a complete standstill. Cars, buses, and trains stop dead in their tracks as people stand while the siren wails. To an outsider, the scene may seem surreal. But, to us Israelis, this serves as a sharp reminder of over 25,000 Israeli soldiers and civilians who have lost their lives in wars, training accidents, and terror attacks.

Continue:

Yom HaAtzmaut Letter 13.4.21

In honor of Israel’s 73rd Independence Day, a beacon was lit this evening by Dr. Dror Dicker, Director of Internal Medicine and the Multidisciplinary Center for the Treatment of Obesity at Hasharon Hospital and a graduate of the Rappaport Faculty of Medicine at the Technion (Class of 1991), The selection committee for this year’s torch-bearers commended Dr. Dicker’s work as: “a paragon of love in the days of Corona: the love of man as a person and a love of the medical profession.”

Dr. Dicker, who was born in Hasharon Hospital, began working there at the age of 16 as a nurse. His father was director of the hospital at the time and his mother was an ECG technician. After completing his medical studies at the Technion, Dr. Dicker returned to the hospital, this time as a physician, where he progressed to the management of the Internal Medicine Department.

Last year, the department he headed was converted into a Corona ward. On March 21st, 2020, his mother died from COVID and Dr. Dicker carried out the “shiva” (7 days mourning period) on the ward, out of commitment to his patients.

Dr. Dicker, 58, has held numerous public positions, including president of the European Federation of Internal Medicine, Chairman of the Israeli Society for the Study and Treatment of Obesity, and co-chair of the European Obesity Care Task Force.

In an article published in Nature Photonics, researchers from Technion – Israel Institute of Technology present a new approach to imaging evanescent waves that allows, among other things, tackling this challenge with the help of “nonlinear wave-mixing,” a combination of two or more light beams that generate a new electromagnetic wave of a different color. This phenomenon, which requires at least one of the light beams to be very intense, occurs in most semiconductors, dielectrics, and metals. The Technion researchers mixed a wide and intense pulsed beam of light with evanescent waves traversing the surface, generating a new light wave that could be subsequently detected by regular means. By doing so, they were able to fully reconstruct the electromagnetic field of the evanescent waves and demonstrated real-time monitoring of changes in the wave pattern.

Guided waves have attracted great attention in recent decades, stimulating the development of various generation and detection methods. Almost all modern communications rely on the guided waves of optical fibers to conduct an enormous amount of information at roughly the speed of light. Large data centers, which are the central hubs for this ocean of information, rely on photonic integrated circuitry – another form of guided light waves – but within a silicon chip, quite like the chips of electrical circuitry. These guided waves do not radiate outside their host structure but still leave a signature in the air – a fast-decaying wave called an evanescent wave. 

Evanescent waves cannot be detected by standard microscopy methods as their energy remains bound to the surface and cannot be seen by the microscope detector. Because of this, designated technologies were developed to detect these waves, using either a small needle approaching the surface, scattering out the electromagnetic power in its vicinity; or by firing electrons on the surface and characterizing their spectrum afterward. Although these two schemes provide an excellent spatial resolution, they require complex and designated infrastructure, as well as long acquisition times, which currently prevent them from imaging the guided waves in real-time.

“The idea to overcome this challenge came to me when I was working on a different project,” said Kobi Frischwasser, the leading author of the manuscript. “I was exploring ways to nonlinearly couple light into confined optical modes when I realized that it could also work the other way around – the information in such modes can be coupled nonlinearly out. I never imagined that this new microscopy scheme could open up new and, so far, unattainable opportunities for near-field science.”

“Aside from bulk materials, nonlinear wave-mixing naturally takes place at any interface between two materials, making it an ideal platform for nanophotonics – which often deals with light at interfaces,” said Professor Guy Bartal of the Andrew & Erna Viterbi Faculty of Electrical Engineering, who headed the project. “Below some spatial limit, Information remains bound to the surface and cannot be seen by any camera. Our technique “releases” this information into radiation that can be detected – even with a commercial camera!” 

The new scheme, termed Nonlinear Near-field Optical Microscopy (NNOM), does not require anything other than a powerful commercial laser source and standard optical components and detectors. According to the researchers, this makes it not only affordable – but also approachable. “You don’t need expensive and complicated tools anymore,” Bartal indicated. “For many applications, all you really need is what you already have in your optics lab.”

In their manuscript, Bartal’s research team, comprised of Kobi Frischwasser, Kobi Cohen, Jacob Kher-Alden, Shimon Dolev, and Shai Tsesses, demonstrated the strength of their scheme in imaging various patterns of electromagnetic surface waves, called surface plasmons, while they change in real-time. “We have been working on simple methods to shape such waves for a while, so it was easy to design field patterns we could freely control,” said Jacob Kher-Alden. 

“The interesting bit was the information we could extract,” added Bartal. “By changing the polarization of the high-intensity pulses, we could see different shapes. We then found out that we are not just measuring the evanescent waves, but we can choose what information to take out of them.” Particularly, the team could separate and visualize the information stored on the “spin” of the evanescent waves, i.e. the clockwise and anti-clockwise rotation of the electric field on the interface.

“When you process the optical information in free-space, everything is much easier,” said Kobi Cohen. “We could see the spatial frequency content of the surface waves, not just the real-space shape, and through a reconstruction algorithm, we managed to extract their phase as well. From here on out, the road to a full-field reconstruction was clear.” 

Finally, the authors demonstrated the application of NNOM by monitoring the changes in digitally encoded surface waves via the use of a spatial light modulator (SLM). “We wanted to show that this new microscopy scheme can have practical applications,” explained Shai Tsesses. “Since there are times when you need to make sure of the exact evanescent pattern, such as in optical trapping and manipulation experiments or when trying to optically address quantum emitters in nanophotonic platforms.”

“We haven’t even begun to explore the limits of this scheme and its applications,” Frischwasser concluded, “It may very well help us to develop better methods of verification for photonic circuitry. We are very excited about the future, and hope that many groups around the world will join us on our quest.”

The research was funded by the Israel Science Foundation and was assisted by the Russell Berrie Nanotechnology Institute, the Zisappel Micro-Nano fabrication unit, and the photovoltaic lab at the Technion. Shai Tsesses is funded by the Israel Academy of Sciences and Humanities through the Adams fellowship program, while Jacob Kher-Alden is funded by a scholarship from the Israeli Council for Higher Education’s Planning and Budgeting Committee.                   

Click here for the paper in Nature Photonics

 

 

Why are there no drugs that can cure COVID-19, SARS, or the flu? Why is it that if you have strep throat, you get prescribed an antibiotic, but with a virus, you are told to sit it out? In short, why are there no antivirals in similar quantity, variety, and effectiveness as antibiotics?

Unlike antibiotics, antiviral drugs are typically designed to target one virus. This narrowness of scope makes it uneconomical for drug companies to invest in developing new antivirals. As a result, non-HIV therapeutics comprise less than 1% of the total therapeutics market, which stands in direct contrast to the dominance of infectious diseases in everyday human experience. While the obvious solution to this problem is to develop antivirals that can be used to treat multiple infectious diseases, finding such broad-spectrum drugs has proven to be a highly elusive goal for the scientific community.

A groundbreaking study conducted in collaboration between the laboratory of Prof. Roee Amit of the Technion – Israel Institute of Technology’s Faculty of Biotechnology and Food Engineering and the group of Prof. Yaron Orenstein from the School of Electrical and Computer Engineering at Ben-Gurion University of the Negev provides a feasible pathway forward to achieving this goal. The study, led by Dr. Noa Katz, demonstrates that a combined synthetic biology and machine learning approach can result in the discovery of molecules which can bind proteins from two distinct viruses. 

The traditional method for identifying therapeutics is to apply a low-throughput and labor-intensive screen for molecules that might perform the required function. In contrast, the synthetic biology and machine learning approach seeks to map the “space” of potential interactions so that molecules with the desired properties can be reliably predicted. This is done by first generating a large and high quality experimental dataset from a library (i.e. collection) of various known and suspected potential virus-protein-binding molecules. The dataset is then used to train a neural network to allow it to form a multidimensional mathematical function representing the collective’s protein-binding capability. 

Once computed, such a function can then be used in reverse. Namely, it can be used to identify regions of high binding capability, and extract “predicted” molecules not previously tested. These unseen or predicted molecules can then be synthesized and tested for the desired biological functionality.  The researchers applied this approach to first map out the binding space of two distinct coat proteins from two different bacteria-attacking viruses, and then synthesized and validated RNA molecules that were predicted to be at the interface between the two spaces, and which therefore possess both functionalities.  This achievement provides the scientific community with a blueprint for an approach that can be used to identify novel RNA sequences that could potentially become key ingredients of broad-spectrum antiviral drugs.

Click here for the paper in Nature Communication