Tag Archives: City University of New York (CUNY)

Bulletproof graphene

A December 18, 2017 news item on Nanowerk announces research that demonstrates graphene can be harder than diamonds (Note: A link has been removed),

Imagine a material as flexible and lightweight as foil that becomes stiff and hard enough to stop a bullet on impact. In a newly published paper in Nature Nanotechnology (“Ultrahard carbon film from epitaxial two-layer graphene”), researchers across The City University of New York (CUNY) describe a process for creating diamene: flexible, layered sheets of graphene that temporarily become harder than diamond and impenetrable upon impact.

Scientists at the Advanced Science Research Center (ASRC) at the Graduate Center, CUNY, worked to theorize and test how two layers of graphene — each one-atom thick — could be made to transform into a diamond-like material upon impact at room temperature. The team also found the moment of conversion resulted in a sudden reduction of electric current, suggesting diamene could have interesting electronic and spintronic properties. The new findings will likely have applications in developing wear-resistant protective coatings and ultra-light bullet-proof films.

A December 18, 2017 CUNY news release, which originated the news item, provides a little more detail,

“This is the thinnest film with the stiffness and hardness of diamond ever created,” said Elisa Riedo, professor of physics at the ASRC and the project’s lead researcher. “Previously, when we tested graphite or a single atomic layer of graphene, we would apply pressure and feel a very soft film. But when the graphite film was exactly two-layers thick, all of a sudden we realized that the material under pressure was becoming extremely hard and as stiff, or stiffer, than bulk diamond.”

Angelo Bongiorno, associate professor of chemistry at CUNY College of Staten Island and part of the research team, developed the theory for creating diamene. He and his colleagues used atomistic computer simulations to model potential outcomes when pressurizing two honeycomb layers of graphene aligned in different configurations. Riedo and other team members then used an atomic force microscope to apply localized pressure to two-layer graphene on silicon carbide substrates and found perfect agreement with the calculations. Experiments and theory both show that this graphite-diamond transition does not occur for more than two layers or for a single graphene layer.

“Graphite and diamonds are both made entirely of carbon, but the atoms are arranged differently in each material, giving them distinct properties such as hardness, flexibility and electrical conduction,” Bongiorno said. “Our new technique allows us to manipulate graphite so that it can take on the beneficial properties of a diamond under specific conditions.”

The research team’s successful work opens up possibilities for investigating graphite-to-diamond phase transition in two-dimensional materials, according to the paper. Future research could explore methods for stabilizing the transition and allow for further applications for the resulting materials.

There’s an artist’s representation of a bullet’s impact on graphene,

By applying pressure at the nanoscale with an indenter to two layers of graphene, each one-atom thick, CUNY researchers transformed the honeycombed graphene into a diamond-like material at room temperature. Photo credit: Ella Maru Studio Courtesy: CUNY

Here’s a link to and a citation for the paper,

Ultrahard carbon film from epitaxial two-layer graphene by Yang Gao, Tengfei Cao, Filippo Cellini, Claire Berger, Walter A. de Heer, Erio Tosatti, Elisa Riedo, & Angelo Bongiorno. Nature Nanotechnology (2017) doi:10.1038/s41565-017-0023-9 Published online: 18 December 2017

This paper is behind a paywall.

D-PLACE: an open access database of places, language, culture, and enviroment

In an attempt to be a bit more broad in my interpretation of the ‘society’ part of my commentary I’m including this July 8, 2016 news item on ScienceDaily (Note: A link has been removed),

An international team of researchers has developed a website at d-place.org to help answer long-standing questions about the forces that shaped human cultural diversity.

D-PLACE — the Database of Places, Language, Culture and Environment — is an expandable, open access database that brings together a dispersed body of information on the language, geography, culture and environment of more than 1,400 human societies. It comprises information mainly on pre-industrial societies that were described by ethnographers in the 19th and early 20th centuries.

A July 8, 2016 University of Toronto news release (also on EurekAlert), which originated the news item, expands on the theme,

“Human cultural diversity is expressed in numerous ways: from the foods we eat and the houses we build, to our religious practices and political organisation, to who we marry and the types of games we teach our children,” said Kathryn Kirby, a postdoctoral fellow in the Departments of Ecology & Evolutionary Biology and Geography at the University of Toronto and lead author of the study. “Cultural practices vary across space and time, but the factors and processes that drive cultural change and shape patterns of diversity remain largely unknown.

“D-PLACE will enable a whole new generation of scholars to answer these long-standing questions about the forces that have shaped human cultural diversity.”

Co-author Fiona Jordan, senior lecturer in anthropology at the University of Bristol and one of the project leads said, “Comparative research is critical for understanding the processes behind cultural diversity. Over a century of anthropological research around the globe has given us a rich resource for understanding the diversity of humanity – but bringing different resources and datasets together has been a huge challenge in the past.

“We’ve drawn on the emerging big data sets from ecology, and combined these with cultural and linguistic data so researchers can visualise diversity at a glance, and download data to analyse in their own projects.”

D-PLACE allows users to search by cultural practice (e.g., monogamy vs. polygamy), environmental variable (e.g. elevation, mean annual temperature), language family (e.g. Indo-European, Austronesian), or region (e.g. Siberia). The search results can be displayed on a map, a language tree or in a table, and can also be downloaded for further analysis.

It aims to enable researchers to investigate the extent to which patterns in cultural diversity are shaped by different forces, including shared history, demographics, migration/diffusion, cultural innovations, and environmental and ecological conditions.

D-PLACE was developed by an international team of scientists interested in cross-cultural research. It includes researchers from Max Planck Institute for the Science of Human history in Jena Germany, University of Auckland, Colorado State University, University of Toronto, University of Bristol, Yale, Human Relations Area Files, Washington University in Saint Louis, University of Michigan, American Museum of Natural History, and City University of New York.

The diverse team included: linguists; anthropologists; biogeographers; data scientists; ethnobiologists; and evolutionary ecologists, who employ a variety of research methods including field-based primary data collection; compilation of cross-cultural data sources; and analyses of existing cross-cultural datasets.

“The team’s diversity is reflected in D-PLACE, which is designed to appeal to a broad user base,” said Kirby. “Envisioned users range from members of the public world-wide interested in comparing their cultural practices with those of other groups, to cross-cultural researchers interested in pushing the boundaries of existing research into the drivers of cultural change.”

Here’s a link to and a citation for the paper,

D-PLACE: A Global Database of Cultural, Linguistic and Environmental Diversity by Kathryn R. Kirby, Russell D. Gray, Simon J. Greenhill, Fiona M. Jordan, Stephanie Gomes-Ng, Hans-Jörg Bibiko, Damián E. Blasi, Carlos A. Botero, Claire Bowern, Carol R. Ember, Dan Leehr, Bobbi S. Low, Joe McCarter, William Divale, Michael C. Gavin.  PLOS ONE, 2016; 11 (7): e0158391 DOI: 10.1371/journal.pone.0158391 Published July 8, 2016.

This paper is open access.

You can find D-PLACE here.

While it might not seem like that there would be a close link between anthropology and physics in the 19th and early 20th centuries, that information can be mined for more contemporary applications. For example, someone who wants to make a case for a more diverse scientific community may want to develop a social science approach to the discussion. The situation in my June 16, 2016 post titled: Science literacy, science advice, the US Supreme Court, and Britain’s House of Commons, could  be extended into a discussion and educational process using data from D-Place and other sources to make the point,

Science literacy may not be just for the public, it would seem that US Supreme Court judges may not have a basic understanding of how science works. David Bruggeman’s March 24, 2016 posting (on his Pasco Phronesis blog) describes a then current case before the Supreme Court (Justice Antonin Scalia has since died), Note: Links have been removed,

It’s a case concerning aspects of the University of Texas admissions process for undergraduates and the case is seen as a possible means of restricting race-based considerations for admission.  While I think the arguments in the case will likely revolve around factors far removed from science and or technology, there were comments raised by two Justices that struck a nerve with many scientists and engineers.

Both Justice Antonin Scalia and Chief Justice John Roberts raised questions about the validity of having diversity where science and scientists are concerned [emphasis mine].  Justice Scalia seemed to imply that diversity wasn’t esential for the University of Texas as most African-American scientists didn’t come from schools at the level of the University of Texas (considered the best university in Texas).  Chief Justice Roberts was a bit more plain about not understanding the benefits of diversity.  He stated, “What unique perspective does a black student bring to a class in physics?”

To that end, Dr. S. James Gates, theoretical physicist at the University of Maryland, and member of the President’s Council of Advisers on Science and Technology (and commercial actor) has an editorial in the March 25 [2016] issue of Science explaining that the value of having diversity in science does not accrue *just* to those who are underrepresented.

Dr. Gates relates his personal experience as a researcher and teacher of how people’s background inform their practice of science, and that two different people may use the same scientific method, but think about the problem differently.

I’m guessing that both Scalia and Roberts and possibly others believe that science is the discovery and accumulation of facts. In this worldview science facts such as gravity are waiting for discovery and formulation into a ‘law’. They do not recognize that most science is a collection of beliefs and may be influenced by personal beliefs. For example, we believe we’ve proved the existence of the Higgs boson but no one associated with the research has ever stated unequivocally that it exists.

More generally, with D-PLACE and the recently announced Trans-Atlantic Platform (see my July 15, 2016 post about it), it seems Canada’s humanities and social sciences communities are taking strides toward greater international collaboration and a more profound investment in digital scholarship.

Sciences Goes to the Movies closes out season one with zombies and opens season two with nanotechnolgy

Thanks to David Bruggeman’s March 9, 2016 posting on his Pasco Phronesis blog for the latest about ‘Science Goes to the Movies’,

The 13th episode of Science Goes to the Movies is now available online, and showing some restraint, the show waited until the end of its first season to deal with zombies.

In other show news, the second season will premiere on CUNY [City University of New York] TV March 18th [2016].  It will focus on nanotechnology.

You can find the 13th episode (running time is almost 30 mins.) embedded in David’s post or you can go to the Science Goes to the Movies webpage on the City University of New York (CUNY) website for the latest video and more information about the episode,

In episode #113 of Science Goes to the Movies, series co-hosts Dr. Heather Berlin and Faith Salie talk with Mark Siddall – a curator at the American Museum of Natural History and President of the American Society of Parasitologists – about zombies!

… Siddall describes different types of parasites that manipulate behavior in a host in order to complete a life cycle or other essential task – including a type of “Dementor” wasp, named after the monster in Harry Potter books, that changes behavior in a cockroach by stinging it. Whether or not zombifying parasites have a taste for brains is also considered, with reference to a species that takes over the bodies of ants, replaces their brains, and uses the ant to complete its life cycle, and The Guinea Worm, a parasite that targets humans for their own reproduction. Siddall then distinguishes between parasites and viruses and explains their similarities.

The Haitian voodoo practice of ingesting neurotoxins to create the effect of “waking from the dead” provides the basis for the next part of the discussion. Dr. Berlin defines neurotoxins and how they work in the brain to block neurons from firing. Tetrodotoxin, in particular, is explained as having a zombifying effect on humans in that its overall paralysis doesn’t affect the brain or the heart, leaving a person fully conscious throughout.

The Wade Davis [emphasis mine] book, The Serpent and The Rainbow, is brought into the discussion, as well as a story about a man kept in a zombie state for two years by ingesting a combination of neurotoxins and hallucinogens. Dr. Berlin breaks down the plausibility of the story and introduces the idea of the “philosopher zombie,” whose zombie status is more conceptual in nature.

28 Days Later and World War Z are discussed as examples of zombie movies in which the cause of the apocalypse is a zombie infection, and Siddall shares news about a cancer with contagious qualities. A recent Centers for Disease Control ad campaign, warning people to prepare for the zombie apocalypse, is mentioned and the real-life potential for human zombies, given the creativity of evolution, makes for the final topic of the show. Before finishing, though, Dr. Berlin and Siddall each share an idea for an original zombie movie.

Written and Produced by Lisa Beth Kovetz.

Wade Davis is a Canadian anthropologist who now teaches at the University of British Columbia.

Should you care to search, you will find a number of posts concerning zombies on this blog.