Devin Carroll, a doctoral candidate in the School of Engineering and Applied Sciences, is designing a modular robot called StickBot, which may be adapted for rehabilitation use in global public health settings.
In late summer, just as the leaves were starting to crisp and curl in the heat, Devin Carroll walked out of his apartment, looked on the ground, and picked up a couple of sticks that he thought might work for his robot. About half an inch thick and the length of an adult hand, he stripped the three sticks of their bark and lashed them with string to StickBot, a modular robot composed of circuitry, actuators, a microcontroller, and a motor driver.
Controlling the robot using an app he designed, Carroll shows how StickBot can pivot from using the sticks as legs in “crawler mode,” to using them as arms. In “grasper mode,” the sticks are attached to a controller plate on one side to form a hinge joint while moving with their free end to hold a cup upright.
Rather than a static, singular invention, StickBot is an idea, a flexible system that can be reconfigured in a variety of ways. A modular robot, StickBot’s components can be added, adjusted, and discarded as needed.
This article features quotes from Michelle Johnson, Associate Professor in Physical Medicine and Rehabilitation in the Perelman School of Medicine and in Bioengineering in the School of Engineering and Applied Sciences, and Director of the Rehabilitation Robotics Lab.
Neuroscientists frequently say that neural activity ‘represents’ certain phenomena, PIK Professor Konrad Kording and postdoc Ben Baker led a study that took a philosophical approach to tease out what the term means.
One of neuroscience’s greatest challenges is to bridge the gaps between the external environment, the brain’s internal electrical activity, and the abstract workings of behavior and cognition. Many neuroscientists rely on the word “representation” to connect these phenomena: A burst of neural activity in the visual cortex may represent the face of a friend or neurons in the brain’s memory centers may represent a childhood memory.
But with the many complex relationships between mind, brain, and environment, it’s not always clear what neuroscientists mean when they say neural activity “represents” something. Lack of clarity around this concept can lead to miscommunication, flawed conclusions, and unnecessary disagreements.
To tackle this issue, an interdisciplinary paper takes a philosophical approach to delineating the many aspects of the word “representation” in neuroscience. The work, published in Trends in Cognitive Sciences, comes from the lab of Konrad Kording, a Penn Integrates Knowledge University Professor and senior author on the study whose research lies at the intersection of neuroscience and machine learning.
With appointments in the Departments of Bioengineering and Electrical and Systems Engineering, as well as the Department of Physics and Astronomy in Penn Arts & Science, and the Departments of Neuroscience and Psychiatry in Penn Perelman’s School of Medicine, Dani S. Bassett is no stranger to following the thread of an idea, no matter where it might lead.
Those wide-ranging fields and disciplines orbit around an appropriate central question: how does the tangle of neurons in our brains wire itself up to learn new things? Bassett, J. Peter Skirkanich Professor and director of the Complex Systems Lab, studies the relationship between the shape of those networks of neurons and the brain’s abilities, especially the way the shape of the network grows and changes with the addition of new knowledge.
To get at the fundamentals of the question of curiosity, Bassett needed to draw on even more disciplines. Fortunately, they didn’t have to look far; Bassett’s identical twin is Perry Zurn, a professor of philosophy at American University, and the two have investigated the many different ways a person can exhibit curiosity.
Bassett and Zurn have now published a new book on the subject. In Curious Minds: The Power of Connection, the twins draw on their previous research, as well as an expansive network of ideas from philosophy, history, education and art.
“It wasn’t clear at the beginning of our careers that we would even ever have a chance to write a book together because our areas were so wildly different,” Bassett says – but then, as postgraduates, Zurn was studying the philosophy of curiosity while Bassett was working on the neuroscience of learning. “And so that’s when we started talking. That talking led to seven years of doing research together,” Bassett says. “This book is a culmination of that.”
How exactly do philosophy and neuroscience complement each other? It all starts with the book’s first, and most deceptively simple question: what is curiosity? “Several investigators in science have underscored that perhaps the field isn’t even ready to define curiosity and how it’s different from other cognitive processes,” says Bassett. The ambiguity in the neuroscience literature motivated Bassett to turn to philosophy, “where there are really rich historical definitions and styles and subtypes that we can then put back into neuroscience and ask: ‘Can we see these in the brain?’”
Michael Mitchell, J. Peter and Geri Skirkanich Assistant Professor of Innovation in the Department of Bioengineering, is one of this year’s recipients of the National Science Foundation’s CAREER Award. The award is given to early-career faculty researchers who demonstrate the potential to be role models in their field and invest in the outreach and education of their work.
Mitchell’s award will fund research on techniques for “immunoengineering” macrophages. By providing new instructions to these cells via nanoparticles laden with mRNA and DNA sequences, the immune system could be trained to target and eliminate solid tumors. The award will also support graduate students and postdoctoral fellows in his lab over the next five years.
The project aligns with Mitchell’s larger research goals and the current explosion of interest in therapies that use mRNA, thanks to the technological breakthroughs that enabled the development of COVID-19 vaccines.
“The development of the COVID vaccine using mRNA has opened doors for other cell therapies,” says Mitchell. “The high-priority area of research that we are focusing on is oncological therapies, and there are multiple applications for mRNA engineering in the fight against cancer.”
A new wave of remarkably effective cancer treatments incorporates chimeric antigen receptor T-cell (CAR-T) therapy. There, a patient’s T-cells, a type of white blood cell that fights infections, are genetically engineered to identify, target and kill individual cancer cells that accumulate in the circulatory system.
However, despite CART-T therapy’s success in treating certain blood cancers, the approach is not effective against cancers that form solid tumors. Because T-cells are not able to penetrate tumors’ fibrous barriers, Mitchell and his colleagues have turned to another part of the immune system for help.
The National Science Foundation’s Research Traineeship Program aims to support graduate students, educate the STEM leaders of tomorrow and strengthen the national research infrastructure. The program’s latest series of grants are going toward university programs focused on artificial intelligence and quantum information science and engineering – two areas of high priority in academia, industry and government.
Chinedum Osuji, Eduardo D. Glandt Presidential Professor and Chair of the Department of Chemical and Biomolecular Engineering (CBE), has received one of these grants to apply data science and machine learning to the field of soft materials. The grant will provide five years of support and a total of $3 million for a new Penn project on Data Driven Soft Materials Research.
Osuji will work with co-PIs Russell Composto, Professor and Howell Family Faculty Fellow in Materials Science and Engineering, Bioengineering, and in CBE, Zahra Fakhraai, Associate Professor of Chemistry in Penn’s School of Arts & Sciences (SAS) with a secondary appointment in CBE, Paris Perdikaris, Assistant Professor in Mechanical Engineering and Applied Mechanics, and Andrea Liu, Hepburn Professor of Physics and Astronomy in SAS, all of whom will help run the program and provide the connections between the multiple fields of study where its students will train.
These and other affiliated faculty members will work closely with co-PI Kristin Field, who will serve as Program Coordinator and Director of Education.
The Penn Center for Precision Engineering for Health (CPE4H) was established late last year to accelerate engineering solutions to significant problems in healthcare. The center is one of the signature initiatives for Penn’s School of Engineering and Applied Science and is supported by a $100 million commitment to hire faculty and support new research on innovative approaches to those problems.
Acting on that commitment, CPE4H solicited proposals during the spring of 2022 for seed grants of $80K per year for two years for research projects that address healthcare challenges in several key areas of strategic importance to Penn: synthetic biology and tissue engineering, diagnosis and drug delivery, and the development of innovative devices. While the primary investigators (PIs) for the proposed projects were required to have a primary faculty appointment within Penn Engineering, teams involving co-PIs and collaborators from other schools were eligible for support. The seed program is expected to continue for the next four years.
“It was a delight to read so many novel and creative proposals,” says Daniel A. Hammer, Alfred G. and Meta A. Ennis Professor in Bioengineering and the Inaugural Director of CPE4H. “It was very hard to make the final selection from a pool of such promising projects.”
Judged on technical innovation, potential to attract future resources, and ability to address a significant medical problem, the following research projects were selected to receive funding.
Evolving and Engineering Thermal Control of Mammalian Cells
Led by Lukasz Bugaj, Assistant Professor in Bioengineering, this project will engineer molecular switches that can be toggled on and off inside mammalian cells at near-physiological temperatures. Successful development of these switches will provide new ways to communicate with cells, an advance that could be used to make safer and more effective cellular therapies. The project will use directed evolution to generate and find candidate molecular tools with the desired properties. Separately, the research will also develop new technology for manipulating cellular temperature in a rapid and programmable way. Such devices will enhance the speed and sophistication of studies of biological temperature regulation.
A Quantum Sensing Platform for Rapid and Accurate Point-of-Care Detection of Respiratory Viral Infections
Combining microfluidics and quantum photonics, PI Liang Feng, Professor in Materials Science and Engineering and Electrical and Systems Engineering, Ritesh Agarwal, Professor in Materials Science Engineering, and Shu Yang, Joseph Bordogna Professor in Materials Science and Engineering and Chemical and Biomolecular Engineering, are teaming up with Ping Wang, Professor of Pathology and Laboratory Medicine in Penn’s Perelman School of Medicine, to design, build and test an ultrasensitive point-of-care detector for respiratory pathogens. In light of the COVID-19 pandemic, a generalizable platform for rapid and accurate detection of viral pathogenesis would be extremely important and timely.
Versatile Coacervating Peptides as Carriers and Synthetic Organelles for Cell Engineering
PI Amish Patel, Associate Professor in Chemical and Biomolecular Engineering, and Matthew C. Good, Associate Professor of Cell and Developmental Biology in the Perelman School of Medicine and in Bioengineering, will design and create small proteins that self-assemble into droplet-like structures known as coacervates, which can then pass through the membranes of biological cells. Upon cellular entry, these protein coacervates can disassemble to deliver cargo that modulates cell behavior or be maintained as synthetic membraneless organelles. The team will design new chemistries that will facilitate passage across cell membranes, and molecular switches to sequester and release protein therapeutics. If successful, this approach could be used to deliver a wide range of macromolecule drugs to cells.
Towards an Artificial Muscle Replacement for Facial Reanimation
Cynthia Sung, Gabel Family Term Assistant Professor in Mechanical Engineering and Applied Mechanics and Computer Information Science, will lead a research team including Flavia Vitale, Assistant Professor of Neurology and Bioengineering, and Niv Milbar, Assistant Instructor in Surgery in the Perelman School of Medicine. The team will develop and validate an electrically driven actuator to restore basic muscle responses in patients with partial facial paralysis, which can occur after a stroke or injury. The research will combine elements of robotics and biology, and aims to produce a device that can be clinically tested.
“These novel ideas are a great way to kick off the activities of the center,” says Hammer. “We look forward to soliciting other exciting seed proposals over the next several years.”
Therapies that use engineered cells to treat diseases, infections and chronic illnesses are opening doors to solutions for longstanding medical challenges. Lukasz Bugaj, Assistant Professor in Bioengineering, has been awarded a National Science Foundation CAREER Award for research that may be key to opening some of those doors.
Such cellular therapies take advantage of the complex molecular mechanisms that cells naturally use to interact with one another, enabling them to be more precise and less toxic than traditional pharmaceutical drugs, which are based on simpler small molecules. Cellular therapies that use engineered immune system cells, for example, have recently been shown to be highly successful in treating certain cancers and protecting against viral infections.
However, there is still a need to further fine-tune the behavior of cells in these targeted therapies. Bugaj and colleagues are addressing that need by developing new ways to communicate with engineered cells once they are in the body, such as turning molecular events on and off at specific times.
The research team recently discovered that both temperature and light can act as triggers of a specific fungal protein, dynamically controlling its location within a mammalian cell. By using light or temperature to instruct that protein to migrate toward or away from the cell’s membrane, Bugaj and his colleagues showed how it could serve as a key component in controlling the behavior of human cells.
A new interview in Penn Medicine News examines Penn Health-Tech (PHT) five years after its founding. PHT began as an experimental collaborative effort between the Perelman School of Medicine, the School of Engineering and Applied Science, and the Office of the Vice Provost for Research to provide funding, advising, and resources to empower innovators to develop transformative devices and technologies in the Penn community. Specifically, PHT specializes in connecting innovators from across Penn’s campus and schools to connect and to develop technology and medical devices to answer some of the most pressing needs in healthcare. Katherine (Katie) Reuther, Practice Associate Professor in Bioengineering, was appointed Executive Director of PHT in 2021 and is leading this venture into the next phase of its growth. Reuther, an alumna of Penn Bioengineering, followed up her doctoral studies with a M.B.A. from Columbia University and subsequently stayed at Columbia as Senior Lecturer in Design, Innovation, and Entrepreneurship in the Department of Biomedical Engineering. As such, her experience and expertise in the fields of both biomedical engineering and entrepreneurship position her well to shepherd PHT into its fullest potential:
“What appealed to me most about the position was a strong foundation, deep resources, and the potential and room to do more, including the opportunity to elevate Penn and Philadelphia as a national hub for health-technology innovation.”
With its irregularities and anatomical complexities, the root canal system is one of the most clinically challenging spaces in the oral cavity. As a result, biofilm not fully cleared from the nooks and crannies of the canals remains a leading cause of treatment failure and persistent endodontic infections, and there are limited means to diagnose or assess the efficacy of disinfection. One day, clinicians may have a new tool to overcome these challenges in the form of microrobots.
In a proof-of-concept study, researchers from Penn Dental Medicine and its Center for Innovation & Precision Dentistry (CiPD), have shown that microrobots can access the difficult to reach surfaces of the root canal with controlled precision, treating and disrupting biofilms and even retrieving samples for diagnostics, enabling a more personalized treatment plan. The Penn team shared their findings on the use of two different microrobotic platforms for endodontic therapy in the August issue of the Journal of Dental Research;the work was selected for the issue’s cover.
“The technology could enable multimodal functionalities to achieve controlled, precision targeting of biofilms in hard-to-reach spaces, obtain microbiological samples, and perform targeted drug delivery, ” says Dr. Alaa Babeer, lead author of the study and a Penn Dental Medicine Doctor of Science in Dentistry (DScD) and endodontics graduate, who is now within the lab of Dr. Michel Koo, co-director of the CiPD .
In both platforms, the building blocks for the microrobots are iron oxide nanoparticles (NPs) that have both catalytic and magnetic activity and have been FDA approved for other uses. In the first platform, a magnetic field is used to concentrate the NPs in aggregated microswarms and magnetically control them to the apical area of the tooth to disrupt and retrieve biofilms through a catalytic reaction. The second platform uses 3D printing to create miniaturized helix-shaped robots embedded with iron oxide NPs. These helicoids are guided by magnetic fields to move within the root canal, transporting bioactives or drugs that can be released on site.
“This technology offers the potential to advance clinical care on a variety of levels,” says Dr. Koo, co-corresponding author of the study with Dr. Edward Steager, a senior research investigator in Penn’s School of Engineering and Applied Science. “One important aspect is the ability to have diagnostic as well as therapeutic applications. In the microswarm platform, we can not only remove the biofilm, but also retrieve it, enabling us identify what microorganisms caused the infection. In addition, the ability to conform to the narrow and difficult-to-reach spaces within the root canal allows for a more effective disinfection in comparison to the files and instrumentation techniques presently used.”
Michel Koo is a professor in the Department of Orthodontics and divisions of Community Oral Health and Pediatric Dentistry in Penn Dental Medicine and co-director of the Center for Innovation & Precision Dentistry. He is a member of the Penn Bioengineering Graduate Group.
With one of its key missions to develop a new generation of scientists at the interface of dental medicine and engineering, the Center for Innovation & Precision Dentistry (CiPD) has selected its inaugural class of fellows for its new postdoctoral training program.
The CiPD was awarded a $2.5 million T90/R90 grant from the National Institute of Dental and Craniofacial Research (NIDCR) last summer to establish the program, recently naming this first cohort of fellows that includes Justin Burrell, Marshall Padilla, Zhi Ren, and Dennis Sourvanos.
“We’re hoping this program will promote cross-pollination and create a culture between these two fields to help dentists develop innovative strategies with engineers,” says Penn Dental Medicine’s Michel Koo, Co-Director of CiPD, who launched the Center in 2021 with Co-Director Kathleen Stebe, Richer & Elizabeth Goodwin Professor in Penn Engineering’s Department of Chemical and Biomolecular Engineering. “Dentists can learn from engineering principles and tools, and engineers can understand more about the needs of the dental and craniofacial fields. We’re providing a platform for them to work together to address unmet clinical needs and develop careers in that interface.”
The NIDCR T90/R90 Postdoctoral Training Program aims to specifically focus on the oral microbiome, host immunity, and tissue regeneration, each of which ties into different aspects of oral health, from tooth decay and periodontal disease to the needs of head and neck cancer patients. To advance these areas, emerging approaches, from advanced materials, robotics, and artificial intelligence to tissue engineering, chloroplast- and nanoparticle-based technologies, will be leveraged.
As part of the two-year training, each postdoc will receive co-mentorship from faculty from each school in conjunction with a career development committee of clinicians, basic scientists, as well as engineers. These mentorships will be focused on research outcomes and readying participants to submit grants and compete for positions in academia or industry.
The inaugural class of fellows includes Justin Burrell, a postdoctoral student in the lab of D. Kacy Cullen, Associate Professor of Neurosurgery; Marshall Padilla, a postdoc in the lab of Michael J. Mitchell, Skirkanich Assistant Professor of Innovation in Bioengineering; and Zhi Ren, a postdoc in the lab of Michael Koo; and Dennis Sourvanos, an Advanced Graduate Dental Education resident at Penn Dental Medicine whose research has been co-directed by Timothy C. Zhu, Professor of Radiation Oncology in the Perelman School of Medicine. Cullen, Mitchell, Koo and Zhu are all members of the Penn Bioengineering Graduate Group.