Scanning the Meeting—Postscript

Special Message

The 2018 MRS Spring Meeting & Exhibit came to a successful conclusion on Friday, April 6, with over 4,000 attendees. Our congratulations go to the Meeting Chairs Edward Botchwey, Catherine Dubourdieu, Quanxi Jia, Shane Kennett, and Cheolmin Park for putting together an excellent technical program along with various special events. MRS would also like to thank all the Symposium Organizers, Session Chairs, and Symposium Assistants for their part in the success of this meeting. We also thank our Sponsors and Exhibitors.

Contributors to news on the 2018 MRS Spring Meeting & Exhibit include Meeting Scene reporters Maria Torres Arango, Antonio Cruz, Dale Karas, Judy Meiksin (@Judy_Meiksin), Don Monroe, Ashley White, Frieda Wiley (@Frieda_Wiley), and Lori Wilson; with photographer Rebecca Tokarczyk; newsletter production by Erin Hasinger and Joe Yzquierdo; Bloggers Matthew Diasio (@MatSciMatt), Araceli Hernández-Granados (@AraceliHG02), and Jiajia Lin; and with assistance from Michael Moran.

Thank you for subscribing to the Meeting Scene e-mails from the 2018 MRS Spring Meeting & Exhibit. We hope you enjoyed reading them. We welcome your comments and feedback.

Symposium NM13—Functionalization of Topological Materials

Highlights of the Friday morning session

Written by Antonio Cruz

Sometimes science needs to take risks, motivated by pure discovery rather than by the promise of technological applications. The National Science Foundation is one of the most prominent US government organizations that provides funding for such risks. The Friday morning session on “Enabling Quantum Leap—Braiding and Fusing Majoranas,” researchers presented some of their results studying Majorana modes. Eric Rowell from Texas A&M University described his work developing mathematical models of anyons, of which Majorana fermions are a type. Other researchers discussed their difficulties and successes in studying braiding of Majorana fermions, where in space the modes are located, and devices that exploit them. Sergey Frolov of the University of Pittsburgh concluded the session, and remarked that braiding is a difficult experiment, and all current proposed schemes are “crazy.” This work lies at the intersection of disparate fields—materials science, mathematics, physics—and it will take everyone working together to study it effectively.

Making the Most of an MRS Meeting

So the MRS meeting is now over, and we're all back home, but that means it's time to start planning ahead for your next one. As students, there's a lot for us to see and do. Here's some tips to consider when you go to your next MRS meeting.

• If you can, go to the MRS chapter mixer. I couldn't do it at the Fall 2017 meeting because my flight got in too late, but this time I was able to come in at the last minute. No one else from my department was at this meeting (and I only found out later that two other people from my university were coming), so the mixer was a great chance to meet other students and I quickly ran into two other people who were also the only ones from their institutions and we chatted about our work. Then we got invited to go with other students to see bars and restaurants nearby, and I kept in touch with a lot of those people through the week.
• Go to sessions beyond your own symposium. MRS is interdisciplinary, so it's worth it to see what other people are doing in the broad materials community that it gathers. Get inspired about potential applications of your own materials, or just broaden your knowledge. I spent a lot of time at the AI symposium because it was a new field I didn't know much about. This is also made easier if you do the first tip, because you can check out talks other MRS students are presenting or they recommend seeing. 
• Check out the exhibitors, even if you're not looking for new supplies Nearly all the exhibitors are not expecting students to buy anything, so don't worry about that. But they'll gladly talk to you about your products and answer your questions, so maybe you can learn more about how to solve experimental problems you might be having or just ask more questions about supplies and get faster feedback than email. At this meeting, I talked to a company that makes instruments to characterize particles. I mentioned we had an older version of the one they were displaying, and they asked how our lab's instrument was doing. When I said I didn't use it much yet and mentioned that I was going to need to train myself because no one currently in the lab has used it before, they offered to send me tutorial materials. Also, MRS has booths talking about other activities the society does so it's cool to learn what else you can support. 
• Bring some business cards! They're a great way to share contact info with other students, professors, and exhibitors. If you're really looking for a job, bring your resume, but business cards are more convenient to just share contact info. Some schools may provide cards for their students, but you can also find good ones for a cheap price online now. You'll probably end up with more than you need, but you can give them out at other events from then on.
• Don't be afraid to talk to more senior researchers. If there's someone you really want to talk to after a session, go for it. People are generally enthusiastic about sharing their work and enjoy getting to talk more if you have questions. At worst, you might only get a short answer to a question, but you might also get to have a good conversation and connections for your work. 

Symposium NM12: Transitioning Quantum Dots from Benchtop to Industry

Ethel Koranteng, University College London

Light-Activated Surfaces for Reducing Hospital Acquired Infections

Written by Maria Torres Arango

Reducing the impact of hospital acquired infections (HAIs) represents a huge challenge for the healthcare sector due to the increasing antimicrobial resistance developed by bacterial populations in hospital environments, costing billions and affecting patients and medical personnel. This problem has been identified to be a consequence of excessive and sometimes unnecessary use of antibiotics. Luckily, innovative efforts to address this issue seem to become increasingly feasible from the antibacterial activity of quantum dots (QD) when exposed to light. Ethel Koranteng from University College London shared their efforts to develop antibiotic-free disinfecting agents based on the synergistic effect of newly available non-toxic cadmium-free QD and crystal violet. As Koranteng mentioned in her talk, this combination enables the use of a wider range of the visible-light spectrum to maximize the antibacterial activity, resulting in efficacies of 99.99% and 99.97% in killing laboratory strains of Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA), respectively.

Interdisciplinary topics MRS

During this MRS spring 2018, MRS gave me the opportunity not only to attend the topic of my interest like perovskite solar cells, I also tried this year to open my mind and attend some other talks outside my "comfort zone".  

For that reason I attended the session of energy like EP04: Advanced Materials for Carbon Capture and Other Important Gas Separations (EP04.01 and EP04.02); it went well; the titles of these talks were: novel devices for the morning session and transistors reliability for the afternoon session. After that I moved on Wednesday into topics related with my material (perovskite) but now for tandem solar applications, and I attended the EN08.06: Tandem Solar Cell Integration; it went really well, due to I obtained more knowledge about it. One talk that caught more my attention was the EN08.06.04: A third option for integrating hybrid tandem solar cells-Three terminal devices, given by Emily Warren from the NREL, Golden Colorado, United States. I never had the opportunity to read about tandem solar cells with 3 contacts, so I learned a lot in here; she  mainly discuss the design and operating principles of three-terminal (3T) tandem cells fabricated by combining a III-V (GaInP or GaAs) top-cell with a 3T Si bottom cell. Also she showed some simulations done to prove that this 3 terminal will provide an efficient mechanism to capture the solar spectrum without the need to current match sub-cells (as in monolithic 2-terminal tandem) or fabricate complicated metal grids/interconnects between cells (as in 4T stacked tandem). Very interesting! 

Then I had a great opportunity given by Jiajia Lin, I could not miss it. She invited me to her talk SM05.01.04 : In Vitro Degradation and Characterization of Hydroxyapatite Coated Magnesium for Implant Application from the University of California, Riverside, Riverside, California, United States. She showed the degradation property of Hydroxyapatite (HA), which I learned it was a naturally occurring calcium-containing mineral that is enriched with magnesium, carbonate acid, phosphate, and other trace elements and it was coated Mg prepared by IonTite^TM, and it was tested in in revised simulated body fluid (rSBF) for six weeks. And with the studies she presented they found out that the HA coated Mg substrates are promising materials as bioresorabable implants for orthopedic and craniofacial applications, and confirmed the optimal IonTite^TM process conditions that could produce HA coatings on Mg with superior degradation performance. Then I also learned that bioresorbable implants are being widely used for fracture fixation in orthopaedic surgery and the market is expanding rapidly worldwide. I hope I can see Jiajia's work in the market pretty soon. 

I still have a great experience going on in my mind, why on my mind?  Well, due to now I want to know more about other materials too and probably move my research to other applications as well. I hope you had that feeling too, and you found the MRS very productive for your research and your future work. 

Thank you MRS 2018 and the speakers mentioned! 

 

-Araceli H.G-

Instituto de Energías Renovables, UNAM-Temixco, Morelos, Mexico. 

 

Symposium X - David J. Mooney introduced fascinating founding in biomaterials

David J. Mooney,  a Professor of Bioengineering at the Harvard School of Engineering and Applied Sciences as well as a core faculty member at the Wyss Institute for Biologically Inspired Engineering at Harvard University, was invited as an honored speaker in the MRS Symposium X meeting. Mooney is a member of both the National Academy of Engineering and the National Academy of Medicine. The Mooney lab focuses on designing biomaterials that affect specific cells functions and making therapies more effective and practical through study of the mechanism of the chemical and mechanical signal that were sensed by cells. His research now focuses on therapeutic angiogenesis, regeneration of musculoskeletal tissues and cancer therapies. In the meeting, he introduced the influence of stress relaxation of hydrogel on cells and demonstrated that faster relaxation of gels promote cell spreading and enhance osteogenesis and new bone formation. Moreover, he put forward that ferrogel with magnetic stimulation can promote new tissue regeneration because active mechanical stimulation share a similar mechanism.

 

Science as Art Awards

First Place Winners:
Yadong Yin, Plum Flower
Magali Ferro, Life Was Growing Everywhere
Peter Sherrell, Nanosucculents

Second Place Winners:
Xin Zhang, ZnO Particle Carbonation
Kanit Hantanasirisakul, Deep Sea Fish
Jonathan Major, Antimony Selenide Dendritic Micro Trees

Graduate Student Awards

Gold Winners:

Alex Ganose, University College London
Zachary Hood, Georgia Institute of Technology
Zhiyuan Liu, Nanyang Technological University
Seongjun Park, Massachusetts Institute of Technology
Ottman Tertuliano, California Institute of Technology *Nowick
Hsinhan Tsai, Rice University
Ying Wang, University of California, Berkeley
Saien Xie, Cornell University

Silver Winners:

Renjie Chen, University of California, San Diego
Jonghyun Choi, University of Illinois at Urbana-Champaign
Zeyu Deng, University of Cambridge
Sreetosh Goswami, National University of Singapore
Bumjin Jang, ETH Zurich
Dohyung Kim, University of California, Berkeley
Shankar Lalitha Sridhar, University of Colorado Boulder
Dingchang Lin, Stanford University
Xiaolong Liu, Northwestern University
Erfan Mohammadi, University of Illinois at Urbana-Champaign
Hongjie Peng, Tsinghua University
Sean Rodrigues, Georgia Institute of Technology
Michael Cai Wang, University of Illinois at Urbana-Champaign
Xiaoxue Wang, Massachusetts Institute of Technology
Shuai Yuan, Texas A&M University
Hyunwoo Yuk, Massachusetts Institute of Technology

Mid-Career Researcher Award—Symposium X Presentation

David Mooney, Harvard University
Biomaterials for Mechanoregeneration

Written by Don Monroe

In his talk about the work that led to his Mid-Career Researcher Award, David Mooney of Harvard University described “mechanoregeneration: the idea of mechanical signals controlling the regeneration of tissues and organs in the body.” In addition to fundamental experiments, he showed how these insights are leading to therapeutic devices.

There is growing recognition that cells respond not only to chemical signals but to mechanical cues. These can be either responses of the surrounding materials to forces the cells generate or externally imposed forces. “Materials can be used to control these mechanical signals,” Mooney said.

Mooney’s team has exploited three-dimensional (3D) alginate hydrogels, which are block-copolymer polysaccharides. Crosslinking occurs between one type of block, but not the other, letting the researchers tune the stiffness to see its effect on stem-cell proliferation, migration, and differentiation. Unlike other systems, “the architecture and the macromolecular transport in these gels does not change as we vary the extent of crosslinking,” Mooney stressed. In addition, cells do not adhere to the underlying gel backbone, but only to small synthetic peptides that the researchers covalently attach.

Experiments “demonstrated unequivocally in 3D that we could control the fate of these cells simply by controlling the stiffness of the gel in which the cells were encapsulated,” Mooney said. For example, mesenchymal stem cells differentiated into fat cells in a soft matrix, but into bone-forming cells in a stiffer matrix.

Beyond the static stiffness, Mooney showed that “fundamental elements of cell biology were dramatically altered by the stress relaxation or viscoelasticity of these hydrogels.” Modifications of this relaxation by changing molecular weight and introducing PEG spacers changed the speed of bone regrowth, and modified the ability of the cells to remodel their matrix.

Clinical application of stem cells today, however, is dominated by IV infusion of individual cells, but almost all of the injected cells are gone within a day. This problem can be addressed by surgically implanting hydrogels, but Mooney illustrated a successful alternative in which the cells are individually embedded in hydrogel using droplet microfluidics. This results in better cell survival, and lets researchers use, for single cells, the gel-modification tricks developed for populations in culture.

Cells and tissue are sensitive not only to mechanical response to forces they generate, but to applied forces, Mooney illustrated for muscle tissue. This insight led to a project, spearheaded by Ellen Roche (now at the Massachusetts Institute of Technology) to develop pneumatically actuated soft-robotic devices to assist heart function and regeneration.

The envisioned device combines two capabilities. First, a mechanical sleeve around the heart provides extra pumping assistance without directly contacting the blood. The team showed that this device significantly enhanced cardiac output in pigs. Second, therapies can be locally provided without additional surgery. This capability is especially important for cellular therapies, Mooney said, where single applications are often insufficient for regeneration.

In his final topic, Mooney described a key requirement for applying forces to tissues, which is adhesion to wet and dynamic tissues. Mooney, former colleague Jeong-Yun Sun, and their collaborators combined the ionically crosslinked polysaccharide network with a covalently crosslinked protein network. The hydrogel “crosslinks can dissipate energy, but the bonds are pretty weak,” Mooney noted. The covalent crosslinks are stronger, but the materials are brittle. The combination provides “an unprecedented level of toughness.” Combining this material with chemistry to bridge the underlying tissue and the hydrogel resulted in tough adhesives that “dramatically outperform anything that has been previously described,” including superglue, Mooney said.

The Mid-Career Researcher Award recognizes exceptional achievements in materials research made by mid-career professionals. The Mid-Career Researcher Award is made possible through an endowment established by MilliporeSigma (Sigma-Aldrich Materials Science). This year’s award was given “for pioneering contributions to the field of biomaterials, especially in the incorporation of biological design principles into materials and the use of biomaterials in mechanobiology, tissue engineering and therapeutics.”