Newsroom – Page 70 – Australian Friends of Tel Aviv University

Human body parts ‘on-a-chip’ could revolutionize drug testing

Written by AUFTAU on 29 January 2020. Posted in Newsroom.

The U.S. Food and Drug Administration (FDA) approves only 13.8% of all tested drugs, and these numbers are even lower in “orphan” diseases that affect relatively few people. Part of the problem lies in the imperfect nature of preclinical drug testing that aims to exclude toxic effects and predetermine concentrations and administration routes before drug candidates can be tested on people. How new drugs move within the human body and are affected by it, and how drugs affect the body itself, cannot be predicted accurately enough in animal and standard in vitro studies. “To solve this massive preclinical bottleneck problem, we need to become much more effective at setting the stage for drugs that are truly promising and rule out others that for various reasons are likely to fail in people,” explains Prof. Donald Ingber, M.D., Ph.D., founding director of Harvard University’s Wyss Institute for Biologically Inspired Engineering, co-author of two new studies on the subject published in Nature Biomedical Engineering. Co-led by Dr. Ben Maoz of Tel Aviv University’s Department of Biomedical Engineering and Sagol School of Neuroscience and over 50 colleagues, a team of scientists at TAU and Harvard have now devised a functioning comprehensive multi-Organ-on-a-Chip (Organ Chip) platform that enables effective in-vitro-to-in-vivo translation (IVIVT) of human drug pharmacology.

Testing on humans, without humans

“We hope that this platform will enable us to bridge the gap on current limitations in drug development by providing a practical, reliable, relevant system for testing drugs for human use,” says Dr. Maoz, co-first author of both studies and former Technology Development Fellow at the Wyss Institute on the teams of Prof. Ingber and Prof. Kevin Kit Parker, Ph.D., the latter of whom is also a leading author of both studies. In the first of two studies, the scientists developed the “Interrogator,” a robotic liquid transfer device to link individual “Organ Chips” in a way that mimics the flow of blood between organs in the human body. Organ Chips are microfluidic devices composed of a clear flexible polymer the size of a computer memory stick that contains two parallel running hollow channels separated by a porous membrane and independently perfused with cell type-specific media. While one of the channels, the parenchymal channel, is lined with cells from a specific human organ or functional organ structure, the other one is lined with vascular endothelial cells presenting a blood vessel. The membrane allows the two compartments to communicate with each other and to exchange molecules like cytokines and growth factors, as well as drugs and drug products generated by organ-specific metabolic activities. The team then applied their Interrogator automated linking platform and a new computational model they developed to three linked organs to test two drugs: nicotine and cisplatin.

Liver on a chip

“The modularity of our approach and availability of multiple validated Organ Chips for a variety of tissues for other human Body-on-Chip approaches now allows us to develop strategies to make realistic predictions about the pharmacology of drugs much more broadly,” says Prof. Ingber. “Its future use could greatly increase the success rates of Phase I clinical trials.” The researchers accurately modeled the oral uptake of nicotine and intravenous uptake of cisplatin, a common chemotherapy medication, and their first passage through relevant organs with highly quantitative predictions of human pharmacokinetic and pharmacodynamic parameters. “The resulting calculated maximum nicotine concentrations, the time needed for nicotine to reach the different tissue compartments, and the clearance rates in the Liver Chips in our in vitro-based in silico model mirrored closely what had been measured in patients,” concludes Dr. Maoz. The multidisciplinary research project is the culmination of a Defense Advanced Research Projects Agency (DARPA) project at the Wyss Institute. Several authors on both studies, including Prof. Ingber, are employees and hold equity in Emulate, Inc., a company that was spun out of the Wyss Institute to commercially develop Organ Chip technology.

New study reveals palace bureaucracy in ancient Samaria

Written by AUFTAU on 24 January 2020. Posted in Newsroom.

The ancient Samaria ostraca — eighth-century BCE ink-on-clay inscriptions unearthed at the beginning of the 20th century in Samaria, the capital of the biblical kingdom of Israel — are among the earliest collections of ancient Hebrew writings ever discovered. But despite a century of research, major aspects of the ostraca remain in dispute, including their precise geographical origins — either Samaria or its outlying villages — and the number of scribes involved in their composition. A new Tel Aviv University study found that just two writers were involved in composing 31 of the more than 100 inscriptions and that the writers were contemporaneous, indicating that the inscriptions were written in the city of Samaria itself. Research for the study was conducted by Ph.D. candidate Shira Faigenbaum-Golovin, Dr. Arie Shaus, Dr. Barak Sober and Prof. Eli Turkel, all of TAU’s School of Mathematical Sciences; Prof. Eli Piasetzky of TAU’s School of Physics; and Prof. Israel Finkelstein, Jacob M. Alkow Professor of the Archaeology of Israel in the Bronze and Iron Ages, of TAU’s Sonia and Marco Nadler Institute of Archaeology.

A palace bureaucracy

The inscriptions list repetitive shipment details of wine and oil supplies to Samaria and span a minimal period of seven years. For archaeologists, they also provide critical insights into the logistical infrastructure of the kingdom of Israel. The inscriptions feature the date of composition (year of a given monarch), commodity type (oil, wine), name of a person, name of a clan and name of a village near the capital. Based on letter-shape considerations, the ostraca have been dated to the first half of the eighth century BCE, possibly during the reign of King Jeroboam II of Israel. “If only two scribes wrote the examined Samaria texts contemporaneously and both were located in Samaria rather than in the countryside, this would indicate a palace bureaucracy at the peak of the kingdom of Israel’s prosperity,” Prof. Finkelstein explains. “Our results, accompanied by other pieces of evidence, seem also to indicate a limited dispersion of literacy in Israel in the early eighth century BCE,” Prof. Piasetzky says.

When math solves history

“Our interdisciplinary team harnessed a novel algorithm, consisting of image processing and newly developed machine learning techniques, to conclude that two writers wrote the 31 examined texts, with a confidence interval of 95%,” said Dr. Sober, now a member of Duke University’s mathematics department.

^{Prof. Israel Finkelstein at a TAU dig in Megido} “The innovative technique can be used in other cases, both in the Land of Israel and beyond. Our innovative tool enables handwriting comparison and can establish the number of authors in a given corpus,” adds Faigenbaum-Golovin. The new research follows up from the findings of the group’s 2016 study, which indicated widespread literacy in the kingdom of Judah a century and a half to two centuries later, circa 600 BCE. For that study, the group developed a novel algorithm with which they estimated the minimal number of writers involved in composing ostraca unearthed at the desert fortress of Arad. That investigation concluded that at least six writers composed the 18 inscriptions that were examined. “It seems that during these two centuries that passed between the composition of the Samaria and the Arad corpora, there was an increase in literacy rates within the population of the Hebrew kingdoms,” Dr. Shaus says. “Our previous research paved the way for the current study. We enhanced our previously developed methodology, which sought the minimum number of writers, and introduced new statistical tools to establish a maximum likelihood estimate for the number of hands in a corpus.”

Featured Image: Inscriptions on pottery fragments from Samaria, the capital of Israel, with added color. The inscriptions date to the first half of the 8th century BCE. (photo: Harvard Semitic Museum)

TAU’s new center will combine medicine and food security

Written by AUFTAU on 23 January 2020. Posted in Newsroom.

Tel Aviv University and Adama, one of the leading companies in plant protection, have launched a unique research and teaching program in the field of delivery (the stage of transporting and linking the active substance to its target site in weeds or agents harmful to plants) and formulation, which is a growth and innovation engine in the field of food, agriculture and plant protection. The innovative curriculum will be taught at the “Adama Center for Advanced Transportation Systems for Plant Protection Materials”, at the School of Chemistry, in collaboration with the School of Plant Sciences and Food Security and the Sackler Faculty of Medicine at Tel Aviv University. As part of the program, researchers and students will be acquiring advanced degrees in Israel and abroad.

Adama offers farmers effective solutions and services for dealing with weeds, pests and lesions and improving their crops. About a year ago, the company inaugurated an innovative research and development center in Neot Hovav, which houses more than 100 researchers. Dozens of collaborations are being conducted at the center with researchers and academics specializing in chemistry, agronomy, agriculture and other fields. Dr. Elad Shabtai, VP of Innovation, Research, Development and Licensing at Adama, explains that until now, delivery and formulation expertise was usually acquired only through working in the industry, and one couldn’t study the field or gain experience through any academic setting in the world. This has created a growing shortage of experts in the field.

The unique curriculum developed by Tel Aviv University and the Adama research and development team will integrate the world of industry and academia, expose students to the field of delivery and formulation, and train the next generation of experts. In addition, Adama will invest in a world-class research lab, set up at the School of Chemistry, where studies and experiments will be conducted. Adama will provide scholarships to approximately 25 students from a variety of fields such as chemistry, materials engineering, plant sciences and more. Students will gain access to advanced soil labs to conduct experiments and undergo practical training by researchers from the company.

Significant connection between academia and industry

At the signing ceremony, held at the company’s research and development center in Neot Hovav, Dr. Chen Lichtenstein, president and CEO of Adama said: “Adama understands that its success in the global, competitive market rests on research and development capabilities as a vehicle for strategic growth. The international center for delivery and formulation that we’re launching at Tel Aviv University will enable us to train the best researchers in the field, and prepare them for entry into the agrochemical industry, so they can develop products that meet the world’s agricultural challenges. “

Prof. Ariel Porat, President of Tel Aviv University, said at the ceremony: “Tel Aviv University attaches great importance to the development of applied research, along with baseline research. To this end, it collaborates with various industries, in various fields. The cooperation with Adama, which we are very pleased about, will contribute much to the advancement of research and teaching in the fields of chemistry, food, agriculture and plant protection, and will benefit the State of Israel.”

Dr. Elad Shabtai, VP of Innovation, Research, Development and Licensing, emphasized: “The connection and ties between academia and industry are significant and central in the context of research and development. We must work to train and strengthen researchers and scientists in the field, starting with the academic stage, to provide a basis for inventions and development.”

Prof. Roey Amir, from the School of Chemistry and head of the Adama Center for Advanced Delivery Systems for Plant Protection Materials at Tel Aviv University, said: “In recent years there has been a demand for smart agriculture development, which will minimize the amount of plant protection materials while improving their operation through advanced delivery systems, similarly to what’s happening in biomedical research. Opening the center will allow us to work together with Adama to train the future generation of scientists who will lead the field in Israel and around the world.”

Siblings of children with intellectual disabilities better at empathy, teaching

Written by AUFTAU on 16 January 2020. Posted in Newsroom.

The sibling relationship is the longest most people will enjoy in their lifetimes and is central to the everyday lives of children. A new Tel Aviv University and University of Haifa study finds that relationships between children and their siblings with intellectual disabilities are more positive than those between typically developing siblings. The research examines the relationships of typically developing children with siblings with and without intellectual disabilities through artwork and questionnaires. It was conducted by Prof. Anat Zaidman-Zait of the Department of School Counseling and Special Education at TAU’s Constantiner School of Education and Dr. Dafna Regev and Miri Yechezkiely of the University of Haifa’s Graduate School of Creative Art Therapies. The study was recently published in Research in Developmental Disabilities. “Having a child with a disability in a family places unique demands on all family members, including typically developing siblings,” Prof. Zaidman-Zait explains. “Although challenges exist, they are often accompanied by both short- and long-term positive contributions.

More empathy, less fighting

“Through our research, we found that relationships among children with siblings with intellectual disabilities were even more supportive than those among typically developed siblings. Specifically, we found that children with siblings with intellectual disabilities scored higher on empathy, teaching and closeness and scored lower on conflict and rivalry than those with typically developing siblings.” Until now, research on how having a sibling with a developmental disability affects children’s social-emotional and behavioral outcomes generated mixed findings. At times, the findings suggested that having a sibling with developmental disabilities led to greater variability in typically developing children’s behavior and adjustment.

“But these studies did little to tap into the inner worlds of children, which really can only be accessed through self-expression in the form of art or self-reporting, independent of parental intervention, which is the route we took in our study,” Prof. Zaidman-Zait says.

Measuring relationships through art

The scientists assessed some 60 children aged 8-11, half with typically developing siblings, half with intellectually disabled siblings, through drawings and a questionnaire about their relationships with their siblings. Mothers of both sets of siblings were also asked to answer a questionnaire about their children’s sibling relationship quality. “We drew on the basic assumption that artistic creation allows internal content to be expressed visually and that children’s self-reports have special added value in studies measuring sibling relationship qualities, especially in areas where parents might have less insight,” Prof. Zaidman-Zait says. Both sets of typically developing children, with and without siblings with intellectual disabilities, were asked to draw themselves and their siblings. Licensed art therapists then used several set criteria to “score” the illustrations: the physical distance between the figures; the presence or absence of a parent in the illustration; the amount of detail invested in either the self-portrait or the sibling representation; and the amount of support given to a sibling in the picture. The children were then asked to complete the Sibling Relationship Questionnaire, which assessed the feelings of closeness, dominance, conflict and rivalry they felt for their siblings. Reviewing the children’s illustrations and questionnaires, as well as the questionnaires completed by the children’s mothers, the researchers found that the children with siblings with intellectual disabilities scored significantly higher on empathy, teaching and closeness in their sibling relationship and scored lower on conflict and rivalry in the relationships than those with typically developing siblings.

“Our study makes a valuable contribution to the literature by using an art-based data gathering task to shed new light on the unique aspects of the relationships of children with siblings with intellectual disabilities that are not revealed in verbal reports,” Prof. Zaidman-Zait concludes. “We can argue that having a family member with a disability makes the rest of the family, including typically developing children, more attentive to the needs of others.” The researchers hope their study, supported by The Shalem Foundation in Israel, will serve as a basis for further research into art-based tools that elicit and document the subjective experience of children.

TAU study among top 12 most important in the world

Written by AUFTAU on 10 January 2020. Posted in Newsroom.

Making the future accessible

Written by AUFTAU on 7 January 2020. Posted in Newsroom.

For many years, if you were vision impaired and wanted to read, you had to know Braille. Invented by Louis Braille, this unique form of tactile writing was introduced to the world in the 1830s and revolutionized access to information for people with visual disabilities. It allowed people the freedom to study, work, earn wages, and live independently, where before these options were extremely limited. By 1960, it was estimated that about 50% of children who were legally blind could read braille in the United States.

But in today’s digital age, new forms of accessibility have become more widespread. We wanted to find out – is Braille still relevant or on its way to becoming extinct?

From text to voice When we asked the staff at TAU’s Sourasky Central Library about books in Braille, we realized we were asking the wrong questions. The library doesn’t have any Braille books, investing instead of more modern forms of accessibility.

“We see accessibility as a very important issue,” says Naama Scheftlowitz, director of the Sourasky Central Library. “But Braille isn’t the most efficient solution these days. We offer students with disabilities more advanced forms consuming text, such as text-to-voice programs and audiobooks. Another benefit is that these forms of accessibility help not just vision-impaired people, but a wide range of students and library patrons. For example, students who don’t speak Hebrew and have difficulty reading, but listening makes it easier for them to study.”

^{Audio is the future}

Every computer at the library comes equipped with “Kolfix”, a text-to-voice program that can read any text on the screen out loud for the user. The library also offers students a subscription to iCast, an Israeli company that provides audiobooks, including translations of foreign books into Hebrew. The library’s search engine, DATA, also has a brand new feature that allows users to “voice search”, meaning to say the search term into a microphone instead of having to type it out.

Putting accessibility in the center

In the lobby of the library lives the Mia and Mila Pinkas Accessibility and Learning Assistance Center, maintained by the Dean of Students. Being placed in the lobby of the building means it’s centrally located on campus, and the library is right there for any assistance. It’s a spacious area containing work stations with advanced technological equipment, including magnification and reading software, and ergonomic equipment, aimed at making studying as accessible as possible for students with disabilities.

^{Some of the work stations at the Mia and Mila Pinkas Accessibility and Learning Assistance Center}

“The very fact that the Accessibility Center is located within the library,” Naama says, “raises awareness of the issue, and we keep up to date with new technologies and adopt them. We even serve as an address for various inquiries to assist with complex student needs.”

TAU study finds widespread misinterpretation of gene expression data

Written by AUFTAU on 27 December 2019. Posted in Newsroom.

Reproducibility of research data is a major challenge in experimental biology. As data generated by genomic-scale techniques increases in complexity, this concern is becoming more and more worrisome. RNA-seq, one of the most widely used methods in modern molecular biology, allows in a single test the simultaneous measurement of the expression level of all genes in a given sample. New research by a Tel Aviv University group identifies a frequent technical bias in data generated by RNA-seq technology, which often leads to false results. The study was conducted by Dr. Shir Mandelbaum, Dr. Zohar Manber, Dr. Orna Elroy-Stein and Dr. Ran Elkon at TAU’s Sackler Faculty of Medicine and George S. Wise Faculty of Life Sciences and was published on November 12 in PLOS Biology. “Recent years have witnessed a growing alarm about false results in biological research, sometimes referred to as the reproducibility crisis,” Dr. Elkon, lead author of the study, says. “This study emphasizes the importance of proper statistical handling of data to lessen the number of misleading findings.”

Removing bias from science

A main goal of RNA-seq experiments is to characterize biological processes that are activated or repressed in response to different conditions. The researchers analyzed dozens of publicly available RNA-seq datasets to profile the cellular responses to numerous stresses. During the research, the scientists noticed that sets of particularly short or long genes repeatedly showed changes in the expression level measured by the apparent number of RNA transcripts from a given gene. Puzzled by this recurring pattern, the team wondered whether it reflected some universal biological response common to different triggers or whether it stemmed from some experimental condition. To tackle this question, they compared replicated samples from the same biological condition. Differences in gene expression between replicates can reflect technical effects that are not related to the experiment’s biological factor of interest. Unexpectedly, the same pattern of particularly short or long genes showing changes in expression level was observed in these comparisons between replicates. This pattern is the result of a technical bias that seemed to be coupled with gene length, the researchers say. Importantly, the TAU researchers were able to show how the length bias they detected in many RNA-seq datasets led to the false identification of specific biological functions as cellular responses to the conditions tested. “Such misinterpretation of the data could lead to completely misleading conclusions,” Dr. Elkon concludes. “In practical terms, the study also shows how this bias can be removed from the data, thus filtering out false results while preserving the biologically relevant ones.”

Fibroblasts involved in healing spur tumor growth in cancer

Written by AUFTAU on 23 December 2019. Posted in Newsroom.

The connective tissue cells known as fibroblasts are vitally important for our recovery from injury. Sensing tissue damage, they gravitate to the site of a wound, instigating an inflammatory response that mends damaged tissue. A new Tel Aviv University study published in Nature Communications finds that fibroblasts also play a devastating role in the development of breast cancer. In cancer tumors, fibroblasts are triggered to respond to tissue damaged by tumors and create inflammation. This inflammation facilitates tumor growth as well as metastases in the lungs. “We have shown, for the first time, that in breast cancer these fibroblasts activate a ‘misguided’ wound healing response, responding to the tissue damage caused by the cancerous growth,” explains Prof. Neta Erez of TAU’s Sackler Faculty of Medicine, who led the research for the study. “Inhibiting these inflammatory signaling pathways may be beneficial in preventing metastatic relapse of breast cancer.” The study was conducted by former TAU student Yoray Sharon and TAU MD-PhD student Nour Ershaid in Prof. Erez’s lab at TAU’s Department of Pathology.

When tumors “hijack” repair functions

According to the study, the inflammatory response of fibroblasts not only supports local tumor growth in the breast, but it also creates a hospitable niche for metastatic growth in the lungs. “The fibroblasts are ‘activated’ and, because of this activation, they recruit immune cells and affect blood vessels,” adds Prof. Erez. “In other words, breast tumors ‘hijack’ the physiologic response to tissue damage to facilitate their growth, and create a niche in a distant organ, the lungs, by ‘remote control.'” Research for the study was performed using transgenic and transplantable mouse models of breast cancer, and validated in human samples of breast cancer and in human expression data. The researchers isolated fibroblasts in transgenic mice from different stages of breast carcinogenesis and profiled the expression of all their genes. They were then able to identify that the inflammation pathway is unregulated in cancer-associated fibroblasts, as compared with fibroblasts isolated from normal mammary glands. Finally, they performed functional experiments to understand the role of this pathway in breast cancer. “Our findings encourage the design of preclinical and clinical studies to examine the benefits of targeting the inflammation pathway in breast cancer, which may be effective in blocking metastatic relapse,” concludes Prof. Erez. “We are now studying the microenvironment of metastasis in an effort to identify targets for preventive intervention that may inhibit metastatic relapse.”

Bringing water to Tanzania

Written by AUFTAU on 18 December 2019. Posted in Newsroom.

Tel Aviv University’s future engineers flew to Africa to connect a school with 1,000 students to clean water

The children living in the villages of Babati district, Tanzania will now have drinkable water during the dry season, thanks to the student delegation from the Iby and Aladar Fleischman Faculty of Engineering. Unfortunately, there are still many places in the world where fresh, clean water, which many in developed countries take for granted, is a rare commodity. This is a common problem in many African countries. Each year, a delegation of engineers from the University of Tanzania sets out to build and improve water and electricity infrastructure. They do so within the framework of the “Engineers Without Borders” association, which works to promote and improve the quality of life of the Israeli population and developing populations worldwide. This year, as in previous years, students responded to the organization’s call, and a delegation of six students flew out during the Sukkot holiday break to contribute their time and knowledge, gained during their studies, and install systems at the regional school that would store 40,000 liters of water.

Months without water

“In Babati district, children sometimes have to walk 10 kilometers to reach clean water reservoirs, or settle for stagnant, contaminated water containing high levels of fluoride, which is detrimental to their health,” says Natalie Lubelchick, a University delegation graduate who is currently completing her master’s degree in Astrophysics. In Tanzania, during the dry season, the local rural population has to cope with three long, hot and dry months. In the absence of a solid infrastructure, the search for drinkable water sources is particularly difficult. If that’s not enough, the same water is also sought by wild animals, who often damage the few existing artificial water reservoirs. The mission of the Israeli delegation, which has sent volunteers for the fifth time, was to build a 40,000-liter water collection system from the rooftops of the Babati district school, where approximately a 1,000 students study, maintain existing systems installed by previous delegations, and also establish a new library, together with the local community. The project is overseen by Prof. Dror Avisar, head of the Water Research Center.

Working together: members of the delegation with locals from the school in Babati district

A glass of water a day for 1,000 children

After a 12-hour flight and before they embarked on two weeks of challenging physical labor, the delegation acquired all the necessary equipment they didn’t bring with them from Israel in Arusha, the city where they landed: dozens of huge 2000-liter containers, each to be installed in a school, as well as pipes and work tools. The main difficulty of this delegation and its predecessors is in being funded. “The ideal situation is that we would have a regular annual budget and know that our operations are guaranteed,” explains Natalie. Sometimes it’s unclear until the day of departure how much money will be at their disposal. On the eve of leaving the city for the village, the delegation members met the Tanzanian community representative, Julius, a school teacher who accompanies the project, and met his family. “He is the delegation’s angel and takes care of all of us,” says Natalie.

Smiles all around: Julius and his family with members of the delegation At the biggest, most central school in Babati district, where the largest system was about to be installed, the delegation was greeted with an enthusiastic welcome. Knowing that soon every student would be able to enjoy clean water was exciting for the children.

Hope and excitement: the delegation is recieved by the young students

At the principal’s office The first order of business for the delegation was teaching a group of boys and girls from local Scouts how to help with the construction and then later on how to maintain the systems. “The idea is not just to build a system, but to work collaboratively with the community, which includes education and instruction, which will lead to long-term results,” Natalie explains.

Left: local Scouts learning the new system. Left: children from the school using it to get clean water.

Left: local Scouts learning the new system. Right: children from the school using it to get clean water. The construction process included installing gutters, cleaning the water tanks and preparing the infrastructure. In one of the schools, where systems had already been installed in the past, the delegation had to replace containers, destroyed by elephants that came in search of water, and build anti-elephant concrete walls around them.

While the systems were being installed, the delegation members taught the students about proper use of the system and “water discipline”, and in return the students taught them local songs and dances.

Singing while you work: two members of the delgation with young students When it was clear that the work was progressing quickly and efficiently, the delegation decided to visit local families and get to know the community. “We started asking them questions about their daily lives and their needs,” Natalie says. “We realized that in addition to building the systems in schools, we also want to think of a home solution. Most people here live in extended families, sometimes numbering up to 50 people. So, a solution for one family can spare them a walk to the nearest water source, which can take hours, and also give them clean water, as opposed to reservoirs that are very polluted. Our challenge was to think of a simple, creative and inexpensive solution, using local materials, so we could easily distribute and duplicate it, and they could easily maintain the systems.”

Sometimes the villagers are forced to drink polluted water

As the largest system was assembled at the Minjingu Elementary School, the principal, together with the teachers, some of the parents and a thousand students, conducted a moving farewell ceremony. “They thanked us with a song, and promised to maintain the system, and we, for our part, got to see and understand how important the system is to them,” Natalie concludes.

Tiny insects become “visible” to bats when they swarm

Written by AUFTAU on 18 December 2019. Posted in Newsroom.

Bats use echolocation to hunt insects, many of which fly in swarms. In this process, bats emit a sound signal that bounces off the target object, revealing its location. Smaller insects like mosquitos are individually hard to detect through echolocation, but a new Tel Aviv University study reveals that they become perceptible when they gather in large swarms. The findings could provide new insights into the evolution of bat echolocation and explain why tiny insects are found in the diets of bats that seem to use sound frequencies that are too high to effectively detect them. The new research was conducted by Dr. Arjan Boonman and Prof. Yossi Yovel at TAU’s Department of Zoology and colleagues at Canada’s Western University. It was published in PLOS Computational Biology on December 12.

Modeling bat vision

Few studies have addressed what swarms of insects — as opposed to single insects — “look” like to bats. To find out, Dr. Boonman and colleagues combined three-dimensional computer simulations of insect swarms with real-world measurements of bat echolocation signals to examine how bats sense swarms that vary in size and density. They found that small insects that are undetectable on their own, such as mosquitos, suddenly become “visible” to bats when they gather in large swarms. They also discovered that the fact that bats use signals with multiple frequencies is well suited to the task of detecting insect swarms. These signals appear to be ideal for detecting an object if more than one target falls inside the echolocation signal beam at once. “Using simulations, we investigated something that could never have been measured in reality,” Dr. Boonman says. “Modeling enabled us to have full control over any aspect of an insect swarm, even the full elimination of the shape of each insect within the swarm.”

From insects to drones

The insect model the researchers used has a tiny mesh (skeleton) and minuscule legs and wings. “We are still adding new features, such as the bat’s acoustic beam or ears, which were not in the original model,” says Prof. Yovel. “We also developed a faster version of the algorithm. All of this will open a new world for us in which we can get echoes even from entire landscapes, so we can learn what a bat or sonar-robot would ‘see’ much more quickly.” The study could also affect technology being developed to improve defense systems. “The algorithms developed for this study could potentially be applied to radar echoes of drone swarms in order to lower the probability of detection by enemy radar,” Dr. Boonman explains. “Since drones are playing an ever more prominent role in warfare, our biological study could spawn new ideas for the defense industry.”

Human body parts ‘on-a-chip’ could revolutionize drug testing

New study reveals palace bureaucracy in ancient Samaria

TAU’s new center will combine medicine and food security