It is one of the Ivy League universities and one of the nine original Colonial Colleges. Incorporated as The Trustees of the University of Pennsylvania, Penn is also one of 14 founding members of the Association of American Universities.
Benjamin Franklin, Penn’s founder, advocated an educational program that focused as much on practical education for commerce and public service as on the classics and theology. Penn was one of the first academic institutions to follow a multidisciplinary model pioneered by several European universities, concentrating multiple “faculties” (e.g., theology, classics, medicine) into one institution. It was also home to many other educational innovations.
The first school of medicine in North America (Perelman School of Medicine, 1765), the first collegiate business school (Wharton, 1881) and the first student union (Houston Hall, 1896) were all born at Penn.
University of Pennsylvania research articles from Innovation Toronto
- Penn Psychologists Study Intense Awe Astronauts Feel Viewing Earth From Space – April 20, 2016
- First Transistors Made Entirely of Nanocrystal Inks – April 8, 2016
- Powerful Machine-Learning Technique Uncovers Unknown Features of Important Bacterial Pathogen – January 25, 2016
- Penn-Led Team Reprograms Social Behavior in Carpenter Ants Using Epigenetic Drugs – January 5, 2016
- Researchers create transplantation model for 3-D printed constructs – November 4, 2015
- This Robot Mimics Your Movements to Transport You to Another Place – October 12, 2015
- Vision-Restoring Gene Therapy Also Strengthens Visual Processing Pathways in Brain – July 16, 2015
- 3D printing of living tissues is easier and cheaper with BioBots – May 7, 2015
- Penn Medicine Bioethicists Call for Return to Asylums for Long-Term Psychiatric Care – January 21, 2015
- T-Cell Therapy Puts Leukemia Patients in Extended Remission – October 18, 2014
- Penn Study Demonstrates Wearable Sensors to Detect Firearm Use – September 8, 2014
- Memory-restoring implants coming from DARPA – July 10, 2014
- Cyborg sensor could unlock anesthesia’s secrets – May 6, 2014
- A new material for solar panels could make them cheaper, more efficient
- VIDEO: 3-D printing creates murky product liability issues
- VIDEO: University of Virginia Engineers are Designing, Building Mechanical Ray
- Penn Study Treats Alzheimer’s by Delivering Protein Across Blood-Brain Barrier
- Penn and Drexel Team Demonstrates New Paradigm for Solar Cell Construction
- Wharton MBA Courses Available Online for Free
- Scientists Demonstrate New Method for Harvesting Energy from Light
- Why the Latest NSA Leak Is the Scariest of All
- New Software Gives Robots the Gift of Hearing
- A Robot That Jumps, Flips, and Does Pull-ups
- Monell-Led Research Identifies Scent of Melanoma
- New Gene Therapy Shows Broad Protection in Animal Models to Pandemic Flu Strains, including the Deadly 1918 Spanish Influenza
- Acrobatic XRL robot takes cliffs and valleys in its stride
- Gecko-Like Drone Can Land On Walls And Ceilings
- All the World’s a Game, and Business Is a Player
- Johns Hopkins Surgeons Implant Brain “Pacemaker” for Alzheimer’s Disease in United States as Part of a Clinical Trial Designed to Slow Memory Loss
- Natural fungus may provide effective bedbug control
- World record quadrocopter swarm puts on impressive light show
- Researchers Make First All-optical Nanowire Switch
- VIDEO: Researchers engineer light-activated skeletal muscle
- Researchers say pharmaceutical ‘innovation crisis’ is a myth
- A Cheaper, Cleaner, More Efficient Catalyst for Burning Methane
- 3D Printed Vascular Networks Made From Sugar
- Mind Reading from Brain Recordings?
- MIT CSAIL Project Could Transform Robotic Design and Production
- U.S. Army Recruiting an Array of Animal-Inspired Robots to Assist Battlefield Troops
- UW Scientists and Colleagues Achieve Breakthrough in Understanding Sense of Touch
- SAFFiR robot could be putting out fires on Navy ships
- Quadrotors perform James Bond theme
- MyHeartMap Challenge
- Breakthrough research paves way for nanomanufacturing in healthcare applications
- Sight Seen: Gene Therapy Restores Vision in Both Eyes
- UPenn’s GRASP lab unleashes a swarm of Nano Quadrotors
- Belt Warns Visually Impaired about Obstacles
- Robot creates other robots out of foam
- The Shark Immunity Factor that Could Save Your Life
- Why We Crave Creativity but Reject Creative Ideas
- Young Entrepreneur Has A Better Idea. Now What?
- To Pique Interest, Start-Ups Try a Digital Velvet Rope
- Can We Be Trained to Like Healthy Foods?
- Autonomous Robots Made to Explore and Map Buildings
- Rejecting Wall Street, Graduates Turn Entrepreneurs Instead
- ‘Wi-fi for energy’ wins Penn invention competition
- Folding Plants Inspire Next Generation of Shape Shifting Robots
- Human protein may help muscular dystrophy patients
- Controlling Cursors With Thoughts
- Sharing of Data Leads to Progress on Alzheimer’s
- Manipulation of the Crowd: How Trustworthy Are Online Ratings?
- The Next Big Thing in the Energy Sector: Photovoltaic Generated DC Electricity
- Tapping a Valuable Resource or Invading the Environment? Research Examines the Start of Fracking in Ohio
- Report proposes microbiology’s grand challenge to help feed the world
- Bubbles are the new lenses for nanoscale light beams
- People may welcome talking tissue boxes and other smart objects
- Device may lead to quicker, more efficient diagnostics
- UConn Professor’s Patented Technique Key to New Solar Power Technology
- NASA announces new CubeSat space mission candidates
- Decoys could blunt spread of ash-killing beetles
- ISIS plays key role in efforts to revolutionize military manufacturing
- Breaking the Mold: Could Additive Manufacturing Resuscitate a Once-Proud U.S. Industry?
- Researchers seek longer battery life for electric locomotive
- Virtual traffic lights help solve commuting hell
- Miniature medical analytic devices that could make Star Trek’s tricorder seem a bit bulky in comparison
- VIDEO: Thought-controlled quadcopter takes to the skies
- Online Obesity Treatment Programmes Show Promise
- Stanford scientists use microbes to make ‘clean’ methane
- Fuel Cell Treats Wastewater and Harvests Energy
- Nanosponges soak up oil again and again
- Intelligent absorbent removes radioactive material from water
- Singularity Summit: Quest for Immortality Never Dies
- Colloidal Quantum Dots: Performance Boost Next-Generation Solar Cell Technology
- Rare-disease studies seek online giving
- Reprogrammed Cells Repair Damaged Livers
- Fruit fly research could lead to simpler and more robust computer networks
- Self-timer for medical paper strip tests developed
- New Way to Tap Gas May Expand Global Supplies
- Researchers working on an invisibility cloak made of glass
- Solar-radiation management could have unwanted regional impacts
- Wi-Fi and 3G could become competitors for mobile Internet access
- New tissue-hugging implants using flexible electronics
Penn researchers help break ground on method to transform cells
Doctors have found a way to manipulate wounds to heal as regenerated skin rather than scar tissue. The method involves transforming the most common type of cells found in wounds into fat cells – something that was previously thought to be impossible in humans. Researchers began this work at the Perelman School of Medicine at the University of Pennsylvania, which led to a large-scale, multi-year study in connection with the Plikus Laboratory for Developmental and Regenerative Biology at the University of California, Irvine. They published their findings online in the journal Science on Thursday, January 5th, 2017.
Fat cells called adipocytes are normally found in the skin, but they’re lost when wounds heal as scars. The most common cells found in healing wounds are myofibroblasts, which were thought to only form a scar. Scar tissue also does not have any hair follicles associated with it, which is another factor that gives it an abnormal appearance from the rest of the skin. Researchers used these characteristics as the basis for their work – changing the already present myofibroblasts into fat cells that do not cause scarring.
“Essentially, we can manipulate wound healing so that it leads to skin regeneration rather than scarring,” said George Cotsarelis, MD, the chair of the Department of Dermatology and the Milton Bixler Hartzell Professor of Dermatology at Penn, and the principal investigator of the project. “The secret is to regenerate hair follicles first. After that, the fat will regenerate in response to the signals from those follicles.”
The study showed hair and fat develop separately but not independently. Hair follicles form first, and the Cotsarelis lab previously discovered factors necessary for their formation. Now they’ve discovered additional factors actually produced by the regenerating hair follicle to convert the surrounding myofibroblasts to regenerate as fat instead of forming a scar. That fat will not form without the new hairs, but once it does, the new cells are indistinguishable from the pre-existing fat cells, giving the healed wound a natural look instead of leaving a scar.
As they examined the question of what was sending the signal from the hair to the fat cells, researchers identified a factor called Bone Morphogenetic Protein (BMP). It instructs the myofibroblasts to become fat. This signaling was groundbreaking on its own, as it changed what was previously known about myofibroblasts.
“Typically, myofibroblasts were thought to be incapable of becoming a different type of cell,” Cotsarelis said. “But our work shows we have the ability to influence these cells, and that they can be efficiently and stably converted into adipocytes.” This was shown in both the mouse and in human keloid cells grown in culture.
“The findings show we have a window of opportunity after wounding to influence the tissue to regenerate rather than scar,” said the study’s lead author Maksim Plikus, PhD, an assistant professor of Developmental and Cell Biology at the University of California, Irvine. Plikus began this research as a postdoctoral fellow in the Cotsarelis Laboratory at Penn, and the two institutions have continued to collaborate.
These discoveries have the potential to be revolutionary in the field of dermatology. The first and most obvious use would be to develop a therapy that signals myofibroblasts to convert into adipocytes – helping wounds heal without scarring.
“It’s highly desirable from a clinical standpoint, but right now it’s an unmet need,” Cotsarelis said.
But the increase of fat cells in tissue can also be helpful for more than just wounds. Adipocyte loss is a common complication of other conditions, especially treatments for HIV, and right now there is no efficient strategy for treatment. The cells are also lost naturally because of the aging process, especially in the face, which leads to permanent, deep wrinkles, something anti-aging treatments can’t fix in a cosmetically satisfactory way.
“Our findings can potentially move us toward a new strategy to regenerate adipocytes in wrinkled skin, which could lead us to brand new anti-aging treatments,” Cotsarelis said.
The Cotsarelis Lab is now focusing on the mechanisms that promote skin regeneration, especially with respect to hair follicle regeneration.
The Plikus Laboratory is focusing on other aspects of cell reprogramming in skin wounds. Researchers there are examining the role of other signaling factory beyond BMP as well as conducting further studies using human cells and human scar tissue.
Learn more: Using Fat to Help Wounds Heal Without Scars
Clinical Study Shows Fluorescent Dye Can Localize Tumors During Surgery in Real-time
An experimental cancer imaging tool that makes tumors glow brightly during surgery has shown promise again in a new Penn Medicine clinical study, this time in patients with brain cancer. The fluorescent dye technique, originally developed by surgeons at the Penn Center for Precision Surgery to treat lung cancer, illuminated brain tumors in real-time during surgery, helping physicians distinguish between healthy and cancerous tissue. Each year, over 15,000 people in the United States undergo surgeries to remove brain tumors.
Findings from the pilot study, led by first author John Y.K. Lee, MD, MSCE, an associate professor of Neurosurgery in the Perelman School of Medicine at the University of Pennsylvania, and co-director of the Center for Precision Surgery, were reported in this week in Neurosurgery.
A big challenge with brain surgery is ensuring the entire tumor is removed. It is difficult to identify the margins of the tumor with current approaches. Cancer tissue not visible to the naked eye or felt by fingers is often missed during tumor removal, leading to recurrence in some patients – about 20 to 50 percent.
Penn’s approach, which relies on an injectable dye that accumulates in cancerous tissues more so than normal tissues, may help change that.
“Fluorescent contrast agents take visualization to a whole new level,” Lee said. “It has the potential for real-time imaging, identification of disease, and most importantly, precise detection of the tumor’s margins. With this, we know better where to cut.”
The study also includes co-author, Sunil Singhal, MD, an associate professor of Surgery, and co-director the Center for Precision Surgery at Penn’s Abramson Cancer Center, who first started work on this approach in his lab nearly 10 years ago.
The technique uses near-infrared, or NIR, imaging and the contrasting agent indocyanine green (ICG), which fluoresces a bright green under NIR light. ICG was developed during World War II as a dye in photography and, in 1958, it was approved by the U.S. Food and Drug Administration (FDA) for use in medicine, primarily in liver diagnostics and later in cardiology.
However, for this study, researchers used a modified version of ICG at a higher concentration delivered intravenously about 24 hours before surgery to ensure margins were included. This is the first time, to the authors knowledge, that this delayed imaging of ICG has been used to visualize brain tumors.
Patients enrolled in the clinical study were between the ages of 20 and 81 with a diagnosis of a solitary brain tumor and a presumed glioma based on imaging or prior surgery or biopsy.
Twelve of the 15 tumors demonstrated strong intraoperative fluorescence. The lack of glow in the three remaining tumors could potentially be due to their disease grade and timing of the injection, the authors suggested.
Eight of the 15 patients demonstrated a visible glow through the dura, a thick membrane on the meninges of the brain, was opened, demonstrating the technology’s ability to see deeply within the brain before the tumor is exposed. Once opened, all tumors were picked up by NIR imaging.
The researchers also studied the surgical margins using neuropathology and magnetic resonance imaging, (MRI) to assess the accuracy and precision of NIR fluorescence in identifying tumor tissue.
Of the 71 specimens collected from MRI-enhanced tumors and their surgical margins, 61 (85.9 percent) fluoresced and 51 of these (71.8 percent) were classified as glioma tissue.
Of the 12 MRI-enhancing gliomas, four patients had biopsy specimens that were both non-fluorescent and negative for tumor, which matched the gross total resection seen on their MRI. In contrast, 8 patients had residual fluorescent signal in the resection cavity. Only 3 of these patients showed gross total resection on MRI. This suggests a benefit of true-negative NIR signal after resection, the authors said.
Over the past three plus years, Singhal, Lee, and their colleagues have performed more than 300 surgeries with the imaging tool in patients with various types of cancer, including lung, brain, bladder and breast.
“This technique, if approved by the FDA, may offer great promise to physicians and patients,” Singhal said. “It’s a strategy that could allow greater precision across many different cancer types, help with early detection, and hopefully better treatment success.”
fMRI Spots More Lies in First Controlled Comparison of the Two Technologies
When it comes to lying, our brains are much more likely to give us away than sweaty palms or spikes in heart rate, new evidence from researchers in the Perelman School of Medicine at the University of Pennsylvania suggests. The study, published in the Journal of Clinical Psychiatry, found that scanning people’s brains with fMRI, or functional magnetic resonance imaging, was significantly more effective at spotting lies than a traditional polygraph test.
It has been demonstrated that when someone is lying, areas of the brain linked to decision-making are activated, which lights up on an fMRI scan for experts to see. While laboratory studies showed fMRI’s ability to detect deception with up to 90 percent accuracy, estimates of polygraphs’ accuracy ranged wildly, between chance and 100 percent, depending on the study. The Penn study was the first to compare the two modalities in the same individuals in a blinded and prospective fashion. The approach adds scientific data to the long-standing debate about this technology and builds the case for more studies investigating its potential real-life applications, such as evidence in the criminal legal proceedings.
Researchers from Penn’s departments of Psychiatry and Biostatistics and Epidemiology found that neuroscience experts without prior experience in lie detection, using fMRI data, were 24 percent more likely to detect deception than professional polygraph examiners reviewing polygraph recordings. In both fMRI and polygraph, participants took a standardized “concealed information” test.
Polygraph, the only physiological lie detector in worldwide use since it was introduced in its present form more than 50 years ago, monitors individuals’ electrical skin conductivity, heart rate, and respiration during a series of questions. Polygraph is based on the assumption that incidents of lying are marked by upward or downward spikes in these measurements. Despite having been deemed inadmissible as legal evidence in most jurisdictions in the United States or for pre-employment screening in the private sector for almost 30 years, polygraph is widely used for government background checks and security clearances.
“Polygraph measures reflect complex activity of the peripheral nervous system that is reduced to only a few parameters, while fMRI is looking at thousands of brain clusters with higher resolution in both space and time. While neither type of activity is unique to lying, we expected brain activity to be a more specific marker, and this is what I believe we found,” said the study’s lead author, Daniel D. Langleben, MD, a professor of Psychiatry.
To compare the two technologies, 28 participants were given the so-called “Concealed Information Test” (CIT). CIT is designed to determine whether a person has specific knowledge by asking carefully constructed questions, some of which have known answers, and looking for responses that are accompanied by spikes in physiological activity. Sometimes referred to as the Guilty Knowledge Test, CIT has been developed and used by polygraph examiners to demonstrate the effectiveness of their methods to subjects prior to the actual polygraph examination.
In the Penn study, a polygraph examiner asked participants to secretly write down a number between three and eight. Next, each person was administered the CIT while either hooked to a polygraph or lying inside an MRI scanner. Each of the participants had both tests, in a different order, a few hours apart. During both sessions, they were instructed to answer “no” to questions about all the numbers, making one of the six answers a lie. The results were then evaluated by three polygraph and three neuroimaging experts separately and then compared to determine which technology was better at detecting the fib.
In one example in the paper, fMRI clearly shows increased brain activity when a participant, who picked the number seven, is asked if that is their number. Experts who studied the polygraph counterpart incorrectly identified the number six as the lie. The polygraph associated with the number six shows high peaks after the participant is asked the same questions several times in a row, suggesting that answer was a lie. The scenario was reversed in another example, as neither fMRI nor polygraph experts were perfect, which is demonstrated in the paper. However, overall, fMRI experts were 24 percent more likely to detect the lie in any given participant.
Beyond the accuracy comparison, authors made another important observation. In the 17 cases when polygraph and fMRI agreed on what the concealed number was, they were 100 percent correct. Such high precision of positive determinations could be especially important in the United States and British criminal proceedings, where avoiding false convictions takes absolute precedence over catching the guilty, the authors said. They cautioned that while this does suggest that the two modalities may be complementary if used in sequence, their study was not designed to test combined use of both modalities and their unexpected observation needs to be confirmed experimentally before any practical conclusions could be made.
During a heart attack, clots or narrowed arteries block blood flow, harming or killing cells within the tissue. But the damage doesn’t end after the crushing pain subsides. Instead, the heart’s walls thin out, the organ becomes enlarged, and scar tissue forms. If nothing is done, the patient can eventually experience heart failure. But scientists now report they have developed gels that, in animal tests, can be injected into the heart to shore up weakened areas and prevent heart failure.
The researchers will present their work today at the 252nd National Meeting & Exposition of the American Chemical Society (ACS). ACS, the world’s largest scientific society, is holding the meeting here through Thursday. It features more than 9,000 presentations on a wide range of science topics. A brand-new video on the research is available at http://bit.ly/ACShydrogels.
Heart attacks strike 750,000 people each year in the U.S., according to the American Heart Association. And more than 5 million U.S. residents are living with heart failure, with symptoms that progress from fatigue and shortness of breath to eventual death. “Heart failure is a huge problem, and few therapies are available for these patients,” says Jason A. Burdick, Ph.D., leader of the study.
Treatments include lifestyle changes, medication, implants or heart transplants. Burdick, who is at the University of Pennsylvania (Penn), explains that these options often don’t work well or, in the case of transplants, are hard to come by. So scientists are pursuing other treatment methods. For instance, researchers at other institutions have done animal studies in which they injected cells into the damaged section of the heart to try to repair damage. To prevent the cells from leaking out, those researchers embedded them in biodegradable “hydrogels” — water-swollen networks of polymer chains with a consistency similar to Jell-OTM. But the scientists noticed something odd when they ran control experiments in which they injected the hydrogel without added cells: Some of the animals’ hearts still showed improvement compared with untreated animals.
Based on those findings, a handful of labs are now experimenting with hydrogel treatments, including two materials that are in clinical trials. Neither is from Burdick’s lab, but as he notes, “It’s important we all keep moving forward to figure out how this therapy could be used, because it’s different than any current treatment.” In addition, different types of hydrogels could suit different patients’ needs.
Some experimental heart attack treatments require surgery to open up the chest, but the two hydrogel materials already in clinical trials are injected into the damaged tissue through a long catheter inserted through the skin — eliminating the need for open-chest surgery.
Burdick and his graduate student Christopher B. Rodell, in collaboration with Robert C. Gorman, M.D., also at Penn, are using this same minimally invasive technique in their own work. But his team has gone a step further by identifying properties that would be useful in treating heart attack patients and then designing hydrogels with those properties. For instance, his group developed a hydrogel that forms additional crosslinks between the polymer chains after injection. The resulting material is stiffer and lasts longer than a gel without these additional crosslinks and the gels in clinical trials.
In fact, Burdick’s gel is unique among hydrogels in providing mechanical support to stabilize the damaged area. In sheep studies, this gel limits formation of scar tissue, thinning of the heart’s walls and enlargement of the heart. By preserving the organ’s size, the gels also reduce leakage of blood through the mitral valve. Together, these benefits maintain the heart’s blood-pumping ability and could stave off heart failure.
The team’s materials are based on hyaluronic acid (HA), a type of sugar molecule that occurs naturally in the body. The researchers modified the HA molecules by attaching adamantane and cyclodextrin groups to allow the gels to flow through catheters, and they added thiol and methacrylate groups to enable post-injection cross-linking to stiffen the hydrogel. Once the researchers finalize the hydrogel formulation and delivery method, they hope to partner with a catheter firm to bring a product to market. Burdick’s team and other research groups are also designing hydrogels that contain drugs or cells that can repair heart tissue.
This research is being presented at a meeting of the American Chemical Society.
Harnessing automated program synthesis allows non-programmers to create working code
Nobody said computer programming was easy. But maybe in the future, it could be.
In order to simplify program development, a National Science Foundation (NSF)-supported project called Expeditions in Computer Augmented Program Engineering (ExCAPE), is developing technology that provides human operators with automated assistance.
“Computers have revolutionized our daily lives, and yet the way we program computers has changed little in the last several decades,” said Rajeev Alur, a professor in the department of computer and information science at the University of Pennsylvania.
Alur heads a team of researchers — representing nine leading computer science programs in the U.S. — that collaborates on the ExCAPE project. NSF supports ExCAPE with a $10 million, five-year Expeditions in Computing award, which funds interdisciplinary research teams working to transform computing and technology.
Alur said the team is taking on a longstanding problem: “Software development remains a tedious and error-prone activity.”
Using a model of programming called automated program synthesis, however, computers can generate pieces of code based on a user’s intent, expressed using various non-code-based forms, such as examples, demonstrations or natural language commands.
“ExCAPE aims to change programming from a purely manual task to one in which a programmer and an automated program synthesis tool can collaborate to generate software that meets its specification,” Alur said.
By removing the need for would-be programmers to learn esoteric programming languages, the method has the potential to significantly expand the number of people engaged in programming in a variety of disciplines, from personalized education to robotics.
Emerging technology known as Software-Defined Networks (SDN) allows network operators to tailor a computer network to the traffic running on it, thereby improving efficiency. Most network operators, however, are not traditional programmers and, as a result, cannot take full advantage of all the technology offers.
To address this shortcoming, the ExCAPE team developed a tool called NetEgg that lets a network operator specify the desired functionality of a switch using examples. NetEgg then automatically generates the code needed to implement that behavior while ensuring maximal throughput for network traffic.
Now patented, NetEgg has already been tested in a classroom setting and forms the basis of an NSF I-Corps project, which will explore the product’s transition to commercial deployment.
Computer-aided education and beyond
Looking at the growing area of online learning, the ExCAPE team further recognized the role that program synthesis tools could play in generating automatic feedback for students — analyzing their solutions, grading their assignments, and providing meaningful explanations of their mistakes.
That’s why the team created Automata Tutor, which has been used by more than 5,000 students from more than 10 universities around the world. Alur and his colleagues presented the results from the early deployment of Automata Tutor in ACM Transactions on Computer-Human Interaction and at theInternational Joint Conference on Artificial Intelligence.
The group has created other tools, including AutoProf, which provides feedback on introductory programming assignments in computer languages, such as Python. Another tool, CPSgrader, automatically grades laboratory courses in cyber-physical systems and provides feedback.
More broadly, the ExCAPE team was able to develop a method that formalized and standardized the core computational problem in emerging synthesis tools. Called Syntax-Guided Synthesis, the new method has allowed the team to build a number of prototype solvers over the past two years.
“This effort has been instrumental in advancing the state-of-the-art in computational approaches, and it has facilitated novel applications of program synthesis, for instance, in automatic optimization of programs for quantum computers,” Alur said.
The ExCAPE team’s research has affected the commercial software world, too. Its notion of syntax-guided synthesis inspired Microsoft to create automated program synthesizers for its suite of software.
“At Microsoft, we have invested significantly in the field of program synthesis, especially programming-by-examples, and with applications to end-user programming,” said Sumit Gulwani, of Microsoft Research, USA.
Microsoft started out by developing domain-specific synthesizers such as FlashFill and FlashExtract, each of which uses examples to generate custom code that improves efficiency. FlashFill, which was released as a feature of Microsoft’s Excel 2013, allows data entered into one column of a worksheet table to be entered in a new table column using only a few keystrokes. FlashExtract, which was included in Microsoft’s PowerShell and Operations Management Suite, extracts structured data from semi-structured log files using examples.
The technology giant has also developed a generic programming-by-example synthesizer called FlashMeta.
“All of our ongoing development of by-example synthesizers at Microsoft for various domains is now being carried out over the FlashMeta framework,” Gulwani said. “In fact, we have set up an entire research and engineering team for development of this framework, called PROSE. This has yielded one order of magnitude effectiveness in the overall development process.”
In years to come, the process of using coding languages for programming may be seen as an evolutionary step in computing, just as other methods replaced the punch cards and assembly languages used to program early computers.
“This project builds on decades of foundational advances in formal methods and programming languages,” says Nina Amla, program director in the Division of Computing and Communication Foundations at NSF. “It signals a paradigm shift in the way we teach basic programming principles, and develop reliable software systems.”
Learn more: Computer programming made easier
Designers of solar cells may soon be setting their sights higher, as a discovery by a team of researchers has revealed a class of materials that could be better at converting sunlight into energy than those currently being used in solar arrays. Their research shows how a material can be used to extract power from a small portion of the sunlight spectrum with a conversion efficiency that is above its theoretical maximum — a value called the Shockley-Queisser limit. This finding, which could lead to more power-efficient solar cells, was seeded in a near-half-century old discovery by Russian physicist Vladimir M. Fridkin, PhD, a visiting professor of physics at Drexel University, who is also known as one of the innovators behind the photocopier.
The team, which includes scientists from Drexel University, the Shubnikov Institute of Crystallography of the Russian Academy of Sciences, the University of Pennsylvania and the U. S. Naval Research Laboratory recently published its findings in the journal Nature Photonics. Their article “Power conversion efficiency exceeding the Shockley-Queisser limit in a ferroelectric insulator,” explains how they were able to use a barium titanate crystal to convert sunlight into electric power much more efficiently than the Shockley-Queisser limit would dictate for a material that absorbs almost no light in the visible spectrum — only ultraviolet.
A phenomenon that is the foundation for the new findings was observed by Fridkin, who is one of the principal co-authors of the paper, some 47 years ago, when he discovered a physical mechanism for converting light into electrical power — one that differs from the method currently employed in solar cells. The mechanism relies on collecting “hot” electrons, those that carry additional energy in a photovoltaic material when excited by sunlight, before they lose their energy. And though it has received relatively little attention until recently, the so-called “bulk photovoltaic effect,” might now be the key to revolutionizing our use of solar energy.
The Limits of Solar Energy
Solar energy conversion has been limited thus far due to solar cell design and electrochemical characteristics inherent to the materials used to make them.
“In a conventional solar cell — made with a semiconductor — absorption of sunlight occurs at an interface between two regions, one containing an excess of negative-charge carriers, called electrons, and the other containing an excess of positive-charge carriers, called holes,”said Alessia Polemi, PhD, a research assistant professor in the Department of Materials Science and Engineering in Drexel’s College of Engineering and one of the co-authors of the paper.
In order to generate electron-hole pairs at the interface, which is necessary to have an electric current, the sunlight’s photons must excite the electrons to a level of energy that enables them to vacate the valence band and move into the conduction band — the difference in energy levels between these two bands is referred to as the “band gap.” This means that in photovoltaic materials, not all of the available solar spectrum can be converted into electrical power. And for sunlight photon energies that are higher than the band gap, the excited electrons will lose it excess energy as heat, rather than converting it to electric current. This process further reduces the amount of power can be extracted from a solar cell.
“The light-induced carriers generate a voltage, and their flow constitutes a current. Practical solar cells produce power, which is the product of current and voltage,” Polemi said. “This voltage, and therefore the power that can be obtained, is also limited by the band gap.”
But, as Fridkin discovered in 1969 — and the team validates with this research — this limitation is not universal, which means solar cells can be improved.
New Life For an Old Theory
When Fridkin and his colleagues at the Institute of Crystallography in Moscow observed an unusually high photovoltage while studying the ferroelectric antimony sulfide iodide — a material that did not have any junction separating the carriers — he posited that crystal symmetry could be the origin for its remarkable photovoltaic properties. He later explained how this “bulk photovoltaic effect,” which is very weak, involves the transport of photo-generated hot electrons in a particular direction without collisions, which cause cooling of the electrons.
This is significant because the limit on solar power conversion from the Shockley-Queisser theory is based on the assumption that all of this excess energy is lost — wasted as heat. But the team’s discovery shows that not all of the excess energy of hot electrons is lost, and that the energy can, in fact, be extracted as power before thermalizing.
“The main result — exceeding [the energy gap-specific] Shockley-Queisser [power efficiency limit] using a small fraction of the solar spectrum — is caused by two mechanisms,” Fridkin said. “The first is the bulk photovoltaic effect involving hot carriers and second is the strong screening field, which leads to impact ionization and multiplication of these carriers, increasing the quantum yield.”
Impact ionization, which leads to carrier multiplication, can be likened to an array of dominoes in which each domino represents a bound electron. When a photon interacts with an electron, it excites the electron, which, when subject to the strong field, accelerates and ‘ionizes’ or liberates other bound electrons in its path, each of which, in turn, also accelerates and triggers the release of others. This process continues successively — like setting off multiple domino cascades with a single tipped tile — amounting to a much greater current.
This second mechanism, the screening field, is an electric field is present in all ferroelectric materials. But with the nanoscale electrode used to collect the current in a solar cell, the field is enhanced, and this has the beneficial effect of promoting impact ionization and carrier multiplication. Following the domino analogy, the field drives the cascade effect, ensuring that it continues from one domino to the next.
“This result is very promising for high efficiency solar cells based on application of ferroelectrics having an energy gap in the higher intensity region of the solar spectrum,” Fridkin said.
Building Toward a Breakthrough
“Who would have expected that an electrical insulator could be used to improve solar energy conversion?” said Jonathan E. Spanier, PhD, a professor of materials science, physics and electrical engineering at Drexel and one of the principal authors of the study. “Barium titanate absorbs less than a tenth of the spectrum of the sun. But our device converts incident power 50 percent more efficiently than the theoretical limit for a conventional solar cell constructed using this material or a material of the same energy gap.”
This breakthrough builds on research conducted several years ago by Andrew M. Rappe, Blanchard Professor of Chemistry and of Materials Science & Engineering at the University of Pennsylvania, one of the principal authors, and Steve M. Young, also a co-author on the new report. Rappe and Young showed how bulk photovoltaic currents could be calculated — which led Spanier and collaborators to investigate if higher power conversion efficiency could be attained in ferroelectrics.
“There are many exciting reports utilizing nanoscale materials or phenomena for improving solar energy conversion,” Spanier said. “Professor Fridkin appreciated decades ago that the bulk photovoltaic effect enables free electrons that are generated by light and have excess energy to travel in a particular direction before they cool or ‘thermalize’—and lose their excess energy to vibrations of the crystal lattice.”
Rappe was also responsible for connecting Spanier to Fridkin in 2015, a collaboration that set in motion the research now detailed in Nature Photonics — a validation of Fridkin’s decades-old vision.
“Vladimir is internationally renowned for his pioneering contributions to the field of electroxerography, having built the first working photocopier in the world,” Rappe said. “He then became a leader in ferroelectricity and piezoelectricity, and preeminent in understanding light interactions with ferroelectrics. Fridkin explained how, in crystals that lack inversion symmetry, photo-excited electrons acquire asymmetry in their momenta. This, in turn, causes them to move in one direction instead of the opposite direction. It is amazing that the same person who discovered these bulk photovoltaic effects nearly 50 years ago is now helping to harness them for practical use in nanomaterials.”
Jonas Salk created a vaccine against polio that has been used since 1955; Albert Sabin created another version that has been on the market since 1961. Together, these two vaccines have nearly eliminated polio from the face of the earth.
Emphasis on nearly. Outbreaks have persisted in developing nations in Asia, Africa and the Americas, in part due to limitations of these vaccines. Most recently, in 2013, Israel reported a “silent” outbreak of polio, in which no one got sick but the virus was found in the environment and in vaccinated individuals.
New research led by University of Pennsylvania scientists offers hope for an alternative. Collaborating with researchers from the U.S. Centers for Disease Control and Prevention and the U.S. Food and Drug Administration, the Penn team developed an oral vaccine booster by manipulating plants to express a protein found in the polio virus. Tests with sera from immunized mice show that the booster confers immunity against all three serotypes of polio.
“Our vaccine research has the potential to provide a timely solution to deal with polio outbreaks around the globe,” said Henry Daniell, professor in the Department of Biochemistry in Penn’s School of Dental Medicine and senior author on the work.
Researchers are one step closer to understanding the genetic and biological basis of diseases like cancer, diabetes, Alzheimer’s and rheumatoid arthritis – and identifying new drug targets and therapies – thanks to work by three computational biology research teams from the University of Arizona Health Sciences, University of Pennsylvania and Vanderbilt University.
The researchers’ findings – a method demonstrating that independent DNA variants linked to a disease share similar biological properties – were published online in the April 27 edition of npj Genomic Medicine.
“The discovery of these shared properties offer the opportunity to broaden our understanding of the biological basis of disease and identify new therapeutic targets,” said Yves A. Lussier, MD, FACMI, lead and senior corresponding author of the study and UAHS associate vice president for health sciences and director of the UAHS Center for Biomedical Informatics and Biostatistics (CB2).
The researchers are striving to better understand the common genetic and biological backgrounds that make certain people susceptible to the same disease. They have developed a method to demonstrate how individual, disease-associated DNA variants share similar biological properties that provide a road map for disease origin.
Over the last ten years, genetics researchers have conducted large studies, called Genome Wide Association Studies (GWAS), which analyze DNA variants across thousands of human genomes to identify those that are more frequent in people with a disease. However, the impact of many of these disease-associated variants on the function and regulation of genes remains elusive, making clinical interpretation difficult.
A method to explore the biological impact of these variants and how they are linked to disease was developed through the collaboration of bioinformatics and systems biology researchers Dr. Lussier;Haiquan Li, PhD, research associate professor and director for translational bioinformatics, Department of Medicine, UA College of Medicine – Tucson; Ikbel Achour, PhD, director for precision health, CB2; Jason H. Moore, PhD, director, Institute for Biomedical Informatics, Perelman School of Medicine, University of Pennsylvania; and Joshua C. Denny, MD, MS, FACMI, associate professor of biomedical informatics and medicine, Vanderbilt University, along with their teams.
In their new paper, the researchers demonstrate that DNA risk variants can affect biological activities such as gene expression and cellular machinery, which together provide a more comprehensive picture of disease biology. When DNA risk variants for a given disease were analyzed in combination, similar biological activities were discovered, suggesting that distinct risk variants can affect the same or shared biological functions and thus cause the same disease. More detailed analyses of variants linked to bladder cancer, Alzheimer’s disease and rheumatoid arthritis showed that two variants can contribute to disease independently, but also interact genetically. Therefore, the precise combination of DNA variants of a patient may work to increase or decrease the relative risk of disease.
Using sugar, silicone and a 3-D printer, a team of bioengineers at Rice University and surgeons at the University of Pennsylvania have created an implant with an intricate network of blood vessels that points toward a future of growing replacement tissues and organs for transplantation.
The study showed that blood flowed normally through test constructs that were surgically connected to native blood vessels.