Creating DNA-based hydrogel bioinks with enhanced mechanical properties for advanced 3D bioprinting applications, such as smart bandages, biosensors, and water filtration membranes. Gaining a better understanding of how trust in the health care system is formed and how it influences patient behavior and outcomes, with the goal of identifying strategies to improve trust and, consequently, public health. Designing a novel influenza vaccine to overcome the challenges of immunosenescence and inflammaging in the elderly, which currently limit the effectiveness of seasonal influenza vaccines.

These are among 44 multidisciplinary endeavors that have been selected to receive support this year from Johns Hopkins University’s Discovery Awards program. Each project team is made up of members from at least two JHU entities who aim to solve a complex problem and expand the horizons of knowledge.

Altogether, the winning project teams—chosen from a record 286 proposals—include 148 individuals representing 11 Johns Hopkins entities.

“As society confronts challenges of increasing complexity, we require solutions that engage different disciplinary perspectives,” JHU President Ron Daniels said. “This year’s Discovery Awards recipients draw on the remarkable strengths of our faculty across our one university, forging new and impactful collaborations with the potential to improve health care, combat climate change, and harness the power of artificial intelligence.”

The Discovery Awards program was launched in early 2015, as was the Catalyst Awards program for early-career researchers. Together the two programs represent a $45 million commitment by university leadership, in tandem with deans and directors of JHU’s divisions, to faculty-led research.

The Discovery Awards are intended to spark new interactions among investigators across the university rather than to support established projects. Teams can apply for up to $100,000 to explore a new area of collaborative work with special emphasis on preparing for an externally funded large-scale grant or cooperative agreement.

“Cross-disciplinary collaboration is vital for solving society’s greatest challenges, from developing innovative health technologies to confronting climate change,” Provost Ray Jayawardhana said. “The Discovery Awards foster those crucial partnerships across Johns Hopkins, unleashing the creative potential of our scholars to drive transformative research. Congratulations to the 2024 awardees!”

This year the Discovery Awards joined forces with the Hopkins Business of Health Initiative, Data Science & AI Institute, Institute for Assured Autonomy, OneNeuro Initiative, and Ralph O’Connor Sustainable Energy Institute to award additional seed funding to related projects. Awarded teams include faculty from computer science, environmental health & engineering, history, materials science & engineering, and research & exploratory development.

The Discovery/DSAI co-funded project “Large Language Models (LLMs) for Knowledge Discovery in the Opioid Industry Documents Archive” brings together the schools of Engineering, Public Health, and Arts & Sciences to develop innovative methods for open-ended corpus analysis using LLMs to analyze the vast Opioid Industry Documents Archive (OIDA). The team aims to uncover key structural determinants of the crisis, such as marketing strategies, prescribing practices, and regulatory failures, while validating their approach by recreating codebooks and analyzing the robustness and consistency of the LLM outputs. The insights gained from this groundbreaking study have the potential to shed new light on the complex factors contributing to the opioid epidemic and inform policy decisions to address this pressing public health issue.

“The Discovery Awards program leverages Hopkins’s unique collaborative culture to support important research ideas at the interface of disciplines,” says Denis Wirtz, vice provost for research. “Expert reviewers helped select the most meritorious ideas from groups of faculty in all divisions of the university, a tall order given the extremely high quality of the proposals this year.”

Teams featuring HEMI Fellows include:

• 3D-LAMMBS: Data-Driven, Deep Learning Architectures for Multiscale Modeling of Biological Systems – Michael Lapera (Applied Physics Lab), Melissa Yates (Applied Physics Lab), Vicky Nguyen (Engineering) & Somdatta Goswami (Engineering) *Co-Funded with the Data Science and AI Institute*
• Advancing Brain Tumor Immunotherapy Informed by Circulating Tumor Cell-Derived Membrane Fragments – Jelani Zarif (Medicine), Claire Hur (Engineering), David Kamson (Medicine) & Stavroula Sofou (Engineering)
• DNA Bioinks for Next-Generation 3D Bioprinting – Angelo Cangialosi (Applied Physics Lab) & Rebecca Schulman (Engineering)
• Harnessing Single-Atom Plasmonic Catalysis for High-Efficiency Energy Transformations – Anthony Shoji Hall (Engineering) & Thomas Kempa (Arts & Sciences) *Co-Funded with the Ralph O’Connor Sustainable Energy Institute*
• Identification of Molecular and Cellular Mechanisms Regulating Sleep Need Using Automated, Selective and Non-stressful Sleep Deprivation in larval Zebrafish – Seth Blackshaw (Medicine), Claire Hur (Engineering) & Mark Wu (Medicine) *Co-Funded with the OneNeuro Initiative*
• Plasmonic Probe and Control of Topological Magnetic States – Natalia Drichko (Arts & Sciences) & Susanna Thon (Engineering)

The full list of recipients and their projects is available on the Office of Research website.

Blink and you’ll miss it: an array of flickering dots, each one mere microns wide, represents the lightning-fast expansion of a crack in glass as a barely perceptible shimmer. 

Using an instrument and approach typically used in medicine and astronomy, a team of Hopkins Extreme Materials Institute (HEMI) researchers has tackled a longstanding challenge in fracture mechanics: understanding and quantifying the behavior of fast cracks in brittle materials like glasses and ceramics.

Led by postdoctoral fellows Liuchi Li and Velat Kiliç, the team used Shack-Hartmann wavefront sensing (SHWFS)—a decades-old method for detecting ophthalmic problems and correcting distortion in telescope images—to map changes in shape and movement that happen in material surrounding rapidly spreading cracks with much higher precision and on much faster timescales than ever before. Their approach appears in Mechanics of Materials.

“Can we make glass that won’t crack? How can we make materials last longer? Once cracking begins, how can we prevent a structure’s total failure? Our unconventional use of this old method enables scientists to tackle these important questions,” said Li.

Making stronger, more resilient glass requires a better understanding of stress intensity factors (SIFs) in highly brittle materials. A measure of stress around or near a crack or flaw in a material, SIFs allow scientists to quantify and predict how cracks evolve. In brittle materials, deformations are very small and the speed at which the ends or edges of cracks as they spread are high, making SIFs difficult to determine using direct measurements.

While theories and simulations allow scientists to predict SIFs, high-resolution experimental data has so far been scarce. One established method, digital image correlation (DIC), can sometimes miss small changes. Another, digital gradient sensing (DGS), is better at tracking those small changes but does not capture as much detail.

Mark Foster, co-author and associate professor of electrical and computer engineering, suggested the team explore SHWFS as a way to map both overall changes and small details in brittle materials under stress.

“Shack-Hartmann wavefront sensing seemed like the ideal solution due to its ability to directly measure surface profiles with high spatial resolution. One thing that is particularly unique here is that we are implementing wavefront sensing at extraordinary frame rates to capture the SIF information,” said Foster.

Both DGS and SHWFS use light to measure surface deformation. However, the Shack-Hartmann sensor used by Li and his colleagues has a spatial resolution of about 10 microns—a hundred times better than the resolution typical of conventional DGS. (For reference, a single human hair has a diameter of around 50 to 100 microns.) This allows the team to get remarkable data about behavior near the crack tip, even though it is moving at hundreds of meters per second.

The team’s SHWFS setup, pictured below, uses a series of lights, lenses, and cameras to transform beams of light into an array of dots. As a crack spreads through a sample, the dots in the array change position slightly, representing changes in the sample’s surface slope. The team compared their results to full-scale 3D finite element simulations to verify their method and experimental measurements.

The team’s SHWFS setup (figures a and b) focuses beams of light through a microlens array to provide an average slope of the sample’s surface over a given area. These slope measurements are represented by an array of dots (figure c), which is captured as a series of images by a camera. As the sample cracks, the dots shift slightly to reflect deformations in its surface. A computer program developed by Li computes the shifts in each dot’s position from one snapshot to the next.

“Our method’s unprecedented spatial resolution allows us to probe fundamental questions in the fracture mechanics of brittle materials, opening the door for predictive dynamic fracture theories for engineering applications,” said Li.

The researchers say that their method could not only inform guidelines for civil engineers but also help in the development of novel materials for consumer electronics and in the defense and aerospace sectors.

“An important next step is to integrate SHWFS with complementary techniques,” says Todd Hufnagel, co-author and professor of materials science and engineering. “For example, x-ray phase-contrast imaging (XPCI) can reveal the precise shape and orientation of the propagating crack tip. The combination of the two techniques will give us unprecedented insight into the nature of dynamic crack propagation in brittle materials.”

Team members included researchers from the departments of Electrical and Computer Engineering, Materials Science and Engineering, and Mechanical Engineering at the Whiting School. In addition to Li, Foster, and Hufnagel, authors include KT Ramesh, Alonzo G. Decker Jr. Professor of Science and Engineering, and HEMI postdoctoral fellows Milad Alemohammad and Lei Yang.

ACKNOWLEDGEMENT STATEMENT:

This project was sponsored in part by the Department of Defense, Defense Threat Reduction Agency under the Materials Science in Extreme Environments University Research Alliance, HDTRA1-20-2-0001. It was also supported in part by the Corning Research and Development Corporation.

Effective August 1, Lori Graham-Brady, professor in the Whiting School of Engineering’s (WSE) Department of Civil and Systems Engineering (CaSE) will serve as the vice dean for faculty for WSE. 

Graham-Brady has served in many leadership roles, including as chair of CaSE, where she helped lead the department’s transformation into the expanded and refocused Department of Civil and Systems Engineering in 2019. She currently holds positions as associate director of the Hopkins Extreme Materials Institute (HEMI), director of the Army Research Lab-funded Center on High-throughput Materials Discovery for Extremes (HT-MAX), and director of the university’s Center on AI for Materials in Extreme Environments (CAIMEE).  

Graham-Brady has also served as the former director of the Center for Materials in Extreme Dynamic Environments (CMEDE) and has led the development of a new facility related to AI for Materials Design (AIMD). From 2008 to 2016, she directed a program under the National Science Foundation’s flagship training program, Integrative Graduate Education and Research Traineeship (IGERT), for 25 PhD students from six departments, with nearly 50% participation by women, first-generation college students, or members of STEM underrepresented minorities.   

Graham-Brady’s research, which spans stochastic mechanics and multiscale materials modeling, has garnered significant funding from various agencies, including the Army Research Labs for implementing multiscale modeling and design of materials for extreme dynamic environments, with particular application in protection materials. 

“With the scale of growth projected for the school, particularly in the number of additional faculty members we will be hiring over the next five years, Lori’s role will be critical in securing top-notch candidates, ensuring their seamless transition into faculty positions within the school, and fostering their success through targeted professional development programs,” said Ed Schlesinger, Benjamin T. Rome Dean of WSE. 

“I’m excited for the opportunity to influence the future of WSE. By helping to recruit the very best faculty and nurturing their growth and advancement, we can continue to ensure that Johns Hopkins maintains its reputation for having the finest educators, scholars, and leaders in the field of engineering,” said Graham-Brady.

A HEMI fellow is among five Johns Hopkins faculty members who have been elected to the American Institute for Medical and Biological Engineering 2024 College of Fellows. Election to AIMBE is among the highest professional distinctions accorded to medical and biomedical engineers and recognizes the top 2% of engineers in these fields. It honors those who have made outstanding contributions to engineering and medicine research, practice, or education.

Fellows were honored during an induction ceremony on March 25 at the AIMBE Annual Event in Arlington, Virginia. Rebecca Schulman, a HEMI fellow and associate professor in the Department of Chemical and Biomolecular Engineering, was among this year’s class of new inductees. She was recognized by the AIMBE “for pioneering contributions to responsive and dynamic biomaterials development by integrating techniques from in vitro synthetic biology.”

Schulman’s research focuses on the development of materials and nanostructures with the capacity for growth, transformation, and response similar to those of biological materials. She uses fundamental ideas from chemical engineering, biology, chemistry, soft matter physics, computer science, and mathematics to design and construct these materials and combines theory, modeling, and experiments in her work. Schulman’s work lies at the interface of structural and dynamic DNA nanotechnology, materials science, and synthetic biology.

From left to right: Ruku Borah, Shane Arlington, Megan Bokhoor, Michael Flickinger, and Tim Weihs.

Preetom (Ruku) Borah, a PhD candidate in the Department of Materials Science and Engineering, earned a Student Presentation Award for his lecture in the Advances in Reactive Materials Engineering Symposium at the 2023 Materials Research Society (MRS) Fall Meeting & Exhibit, held in Boston, Massachusetts in late November. 

Borah works in the lab of Tim Weihs, a professor of materials science and engineering and director of the Materials Science in Extreme Environments University Research Alliance (MSEE URA), where he focuses on approaches to counteracting chemical warfare agents (CWAs). 

Borah’s winning presentation described key findings from experiments with diisopropyl methyl phosphonate (DIMP), a gas simulant. In one study, he ignited a combination of metallic powders to diffuse the effects of DIMP. He found that by controlling the combustion of these powders in the presence of DIMP vapor, the simulant showed signs of decomposition, suggesting neutralization of the gas. The signs of neutralization point toward the possibility of alternate ways to diffuse chemical agents, he said. 

Next, Borah plans to identify ways to control the decomposition of DIMP using various mixtures of aluminum, magnesium, and zirconium.  

“The goal going forward is to see, now that we’ve demonstrated the capability to neutralize DIMP with one chemistry, how can we tune that decomposition?” says Borah. “The next step is to test multiple chemistries, seeing what’s going to improve or detract from that decomposition.”

An interdisciplinary team of Whiting School faculty members has been chosen to receive a U.S. Department of Energy Award.

This four-year, $4.8 million grant from the Department of Energy’s Office of Science promotes research on scientific machine learning focused on greater predictive capabilities for scientific simulations. The award will be managed by the Hopkins Extreme Materials Institute as part of its Center on Artificial Intelligence for Materials in Extreme Environments (CAIMEE).

The team is led by Michael Shields and includes Dimitris Giovanis, Somdatta Goswami (soon joining WSE as a faculty member), Lori Graham-Brady, Yannis Kevrekidis, and Tamer Zaki.

Shields, Giovanis, Graham-Brady, Kevrekidis, and Zaki are HEMI fellows, and Graham-Brady is the director of CAIMEE.

Their project, “Physics and Uncertainty Informed Latent Operator Learning,” seeks to address two of the primary challenges to widespread adoption of scientific machine learning (SciML) methods and their applications in the physical, natural, and engineering sciences: scaling of SciML methods to large-scale problems with highly complex physics and the simultaneous quantification of uncertainty.

It aims to develop novel physics-informed neural operators that exploit the underlying low-dimensional structure of high-dimensional physics-based models which will focus on applications in fracture mechanics of additively manufactured composites and high-speed fluid flow.

Understanding how granular materials and rocks react under stress is crucial to projects ranging from building stable roads and bridges to formulating pills and cosmetics. Soil and rock mechanics are also integral to academic fields such as civil engineering, materials science, geology, and seismology.

When granular materials experience stress, they can start to behave in a fluid-like manner. This behavior is known as plastic flow, and plasticity theories attempt to explain this and related phenomena. Although plasticity theories have been developed and used for decades, there have been no direct stress or strain measurements to validate them, in part because of the significant challenges in directly measuring stress deep within a deforming material.

Using advanced imaging techniques and a unique experimental approach, researchers at the Hopkins Extreme Materials Institute have collected data that is among the first of its kind. Ryan Hurley, assistant professor of mechanical engineering in the Whiting School of Engineering, leads a research group studying the mechanical behavior and failure mechanisms of various geomaterials. Hurley and his collaborators (including mechanical engineering doctoral students Brett Kuwik and Kwangmin Lee and former HEMI postdoctoral fellow Ghassan Shahin) have recently had their findings published in Proceedings of the National Academy of Sciences.

During this study, the team performed triaxial compression tests on synthetic quartz sands, with x-ray imaging and diffraction offering some of the first known in-situ grain stress and local strain measurements.

Using a specialized triaxial compression instrument developed in Hurley’s lab, the researchers placed quartz sand samples under confining pressures between 20 and 35 MPa—2900 to 5000 pounds per square inch (PSI)—and analyzed them using synchrotron x-ray tomography and 3D x-ray diffraction at the Advanced Photon Source at Argonne National Laboratory.

“Results from this study provide the first direct confirmation of some of the fundamental postulates we use when studying the plastic deformation of sands,” said Hurley. “On the other hand, our results contradict prior assumptions such as the existence of ‘dead zones’ outside of regions of localized straining, indicating that some fundamental ideas about plastic flow in granular materials may need to be revisited.”

The team says these findings provide an opportunity for scientists to begin evaluating certain assumptions about how granular materials such as sand respond to stress, re-evaluate old ideas, and validate and expand upon existing models in soil and rock mechanics.

3D x-ray images of sand before and after axial straining, along with renderings of the sample. Sand particles are colored by their motion (instantaneous rotations) and stress. See Hurley’s paper in this edition of PNAS for additional details.

Rebecca Schulman, an associate professor in the Department of Chemical and Biomolecular Engineering, has been named one of 10 2023 Vannevar Bush Faculty Fellows by the U.S. Department of Defense. The five-year, $3 million individual award aims to facilitate the progression of fundamental research, encourage collaboration between researchers and national defense experts, and enable investigators to pursue breakthrough discoveries in their fields.

Schulman, who holds secondary appointments in chemistry and computer science, is a HEMI fellow exploring the interfaces of materials science, biochemistry, circuit design, soft matter physics, and cell-free synthetic biology. Her project, “Self-organizing Biomaterials Using Biomolecular Networks,” will investigate how engineers can build complex machines and materials by applying similar principles to those used in biological development.

“Genes build living things by hierarchically organizing molecules, organelles, cells, tissues, and organs,” said Schulman. “Our project will investigate whether engineers might adopt similar ideas.”

Schulman is looking forward to her fellowship term and expressed gratitude for the people who have assisted her in her efforts so far. Preliminary data and concepts for this fellowship were obtained through an AI for materials seed project funded through the Center for Materials in Extreme Dynamic Environments.

“I am excited about the opportunity to deeply explore new ideas and take risks,” said Schulman.

Impacts by debris and meteoroids pose a significant threat to satellites, space probes, and hypersonic craft. Such high-velocity impacts create a brief, intense burst of light, known as an impact flash. These flashes contain information about both the target and the object that caused the impact. For example, scientists have studied the impact of meteoroids on the moon by monitoring and analyzing impact flashes on its dark side.

A team of Johns Hopkins Whiting School of Engineering researchers led by mechanical engineering doctoral student Gary Simpson, Professor of Science and Engineering K.T. Ramesh, and colleagues have discovered that impact flashes are created by the fragmentation of an ultra-fast jet of material ejected from the colliding bodies. Their results appear in PNAS Nexus.

Working in the Hopkins Extreme Materials Institute’s HyFIRE lab, the team shot stainless steel spheres into an aluminum alloy plate at a speed of three kilometers per second—about 6,700 miles per hour, or more than nine times the speed of sound. The resulting impact flashes were photographed using ultra-high-speed cameras and high-speed spectroscopy, which measures the color and brightness of the light.

Immediately after impact, a luminous disc is seen expanding around the impacting sphere. Only a few millionths of a second later, the disc takes on an almost floral shape, as fragments ejected from the impact crater form an ejecta cone, with petal-like projections at the outer edge.

“We found that minuscule, condensed fragments from the jet interact with the atmosphere to create an extremely bright radiating cloud of vapor, which expands at a speed of over ten kilometers per second, or more than 22,000 miles per hour,” said Simpson. “The material making up the target and the size of the jetted particles can be inferred from the flash.”

Other authors of the study include Justin Moreno, HEMI associate staff engineer, and Matthew Shaeffer, HEMI senior staff engineer. Both are faculty members in applied biomedical engineering at the Whiting School’s Engineering for Professionals program.