Following the people and events that make up the research community at Duke

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Opening the Black Box: Duke Researchers Discuss Bias in AI

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Artificial intelligence has not only inherited many of the strongest capabilities of the human brain, but it has also proven to use them more efficiently and effectively. Object recognition, map navigation, and speech translation are just a few of the many skills that modern AI programs have mastered, and the list will not stop growing anytime soon.

Unfortunately, AI has also magnified one of humanity’s least desirable traits: bias. In recent years, algorithms influenced by bias have often caused more problems than they sought to fix.

When Google’s image recognition AI was found to be classifying some Black people as gorillas in 2015, the only consolation for those affected was that AI is improving at a rapid pace, and thus, incidents of bias would hopefully begin to disappear. Six years later, when Facebook’s AI made virtually the exact same mistake by labeling a video of Black men as “primates,” both tech fanatics and casual observers could see a fundamental flaw in the industry.

Jacky Alciné’s tweet exposing Google’s racist AI algorithm enraged thousands in 2015.


On November 17th, 2021, two hundred Duke Alumni living in all corners of the world – from Pittsburgh to Istanbul and everywhere in between – assembled virtually to learn about the future of algorithms, AI, and bias. The webinar, which was hosted by the Duke Alumni Association’s Forever Learning Institute, gave four esteemed Duke professors a chance to discuss their view of bias in the artificial intelligence world.

Dr. Stacy Tantum, Bell-Rhodes Associate Professor of the Practice of Electrical and Computer Engineering, was the first to mention the instances of racial bias in image classification systems. According to Tantum, early facial recognition did not work well for people of darker skin tones because the underlying training data – observations that inform the model’s learning process – did not have a broad representation of all skin tones. She further echoed the importance of model transparency, noting that if an engineer treats an AI as a “black box” – or a decision-making process that does not need to be explained – then they cannot reasonably assert that the AI is unbiased.

Stacy Tantum, who has introduced case studies on ethics to students in her Intro to Machine Learning Class, echoes the importance of teaching bias in AI classrooms.

While Tantum emphasized the importance of supervision of algorithm generation, Dr. David Hoffman – Steed Family Professor of the Practice of Cybersecurity Policy at the Sanford School of Public Policy – explained the integration of algorithm explainability and privacy. He pointed to the emergence of regulatory legislation in other countries that ensure restrictions, accountability, and supervision of personal data in cybersecurity applications. Said Hoffman, “If we can’t answer the privacy question, we can’t put appropriate controls and protections in place.”

To discuss the implications of blurry privacy regulations, Dr. Manju Puri – J.B. Fuqua Professor of Finance at the Fuqua School of Business – discussed how the big data feeding modern AI algorithms impact each person’s digital footprint. Puri noted that data about a person’s phone usage patterns can be used by banks to decide whether that person should receive a loan. “People who call their mother every day tend to default less, and people who walk the same path every day tend to default less.” She contends that the biggest question is how to behave in a digital world where every action can be used against us.

Dr. Philip Napoli has observed behaviors in the digital world for several years as James R. Shepley Professor of Public Policy at the Sanford School, specifically focusing on self-reinforcing cycles of social media algorithms. He contends that Facebook’s algorithms, in particular, reward content that gets people angry, which motivates news organizations and political parties to post galvanizing content that will swoop through the feeds of millions. His work shows that AI algorithms can not only impact the behaviors of individuals, but also massive organizations.

At the end of the panel, there was one firm point of agreement between all speakers: AI is tremendously powerful. Hoffman even contended that there is a risk associated with not using artificial intelligence, which has proven to be a revolutionary tool in healthcare, finance, and security, among other fields. However, while proven to be immensely impactful, AI is not guaranteed to have a positive impact in all use cases – rather, as shown by failed image recognition platforms and racist healthcare algorithms that impacted millions of Black people, AI can be incredibly harmful.

Thus, while many in the AI community dream of a world where algorithms can be an unquestionable force for good, the underlying technology has a long way to go. What stands between the status quo and that idealistic future is not more data or more code, but less bias in data and code.

Post by Shariar Vaez-Ghaemi, Class of 2025


Keeping the Aging Brain Connected With Words and Music

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In an era of seemingly endless panaceas for age-based mental decline, navigating through the clutter can be a considerable challenge.

However, a team of Duke researchers, led by cognitive neuroscientist Edna Andrews, PhD, think they may have found a robust and long-term solution to countering this decline and preventing pathologies in an aging brain. Their approach does not require an invasive procedure or some pharmacological intervention, just a good ear, some sheet music, and maybe an instrument or two.

Dr. Edna Andrews, pictured in 2017. (Photo by Megan Mendenhall/Duke Photography)

In early 2021, Andrews and her team published one of the first studies to look at musicianship’s impact in building cognitive brain reserve. Cognitive brain reserve, simply put, is a way to qualify the resilience of the brain in the face of various pathologies. High levels of cognitive reserve can help stave off dementia, Parkinson’s disease or multiple sclerosis for years on end. These levels are quantified through structural measurements of gray matter and white matter in the brain. The white matter may be thought of as the insulated wiring that helps different areas of the brain communicate.

In this particular study, Andrews’ team focused on measurements of white matter integrity through an advanced MRI technique known as diffusion tensor imaging, to see what shape it is in.

Previous neuroimaging studies have revealed that normal aging leads to a decrease in white matter integrity across the brain. Over the past fifteen years, however, researchers have found that complex sensory-motor activities may be able to slow down and even reverse the loss of white matter integrity. The two most robust examples of complex sensory-motor activities are multilingualism and musicianship.

Andrews has long been fascinated by the brain and languages. In 2014, she published one of the seminal texts in the field of cognitive neurolinguistics where she laid the groundwork for a new neuroscience model of language. Around the same time, she published the first and to-date only longitudinal fMRI study of second language acquisition. Her findings, built upon decades of research in cognitive neuroscience and linguistics, served as the foundation for her popular FOCUS course: Neuroscience/Human Language.

Dr. Andrews’ 2014 book. Published by Cambridge University Press

In more recent years, she has shifted her research focus to understanding the impact of musicianship on cognitive brain reserve. Invigorated by her lived experience as a professional musician and composer, she wanted to see whether lifelong musicianship could increase white matter integrity as one ages. She and her team hypothesized that musicianship would increase white matter integrity in certain fiber tracts related to the act of music-making

To accomplish this goal, she and her team scanned the brains of eight different musicians ranging in age from 20 years to 67 years old. These musicians dedicated an average of three hours per day to practice and had gained years’ worth of performance experience. After participants were placed into the MRI machine, the researchers used diffusion tensor imaging to calculate fractional antisotropy (FA) values for certain white matter fiber tracts. A higher FA value meant higher integrity and, consequently, higher cognitive brain reserve. Andrews and her team chose to observe FA values in two fiber tracts, the superior longitudinal fasciculus (SLF) and the uncinate fasciculus (UF), based on their relevance to musicianship in previous studies.

Relative location of subcortical white matter fiber tracts (lateral view). Image from Wikipedia

Previous studies of the two fiber tracts in non-musicians found that their integrity decreased with age. In other words, the older the participants, the lower their white matter integrity in these regions. After analyzing the anisotropy values via linear regression, they observed a clear positive correlation between age and fractional anisotropy in both fiber tracts. These trends were visible in both tracts of both the left and right hemispheres of the brain. Such an observation substantiated their hypothesis, suggesting that highly proficient musicianship can increase cognitive brain reserve as one ages.

These findings expand the existing literature of lifestyle changes that can improve brain health beyond diet and exercise. Though more demanding, neurological changes resulting from the acquisition and maintenance of language and music capabilities have the potential to endure longer into the life cycle.

Andrews is one of the strongest advocates of lifelong learning, not solely for the satisfaction it brings about, but also for the tangible impact it can have on cognitive brain reserve. Picking up a new language or a new instrument should not be pursuits confined to the young child.

It appears, then, that the kindest way to treat the brain is to throw something new at it. A little bit of practice couldn’t hurt either.

Post by Vibhav Nandagiri, Class of 2025

Decentralized Finance and the Power of Smart Contracts

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When people use apps or services like Netflix, Instagram, Amazon, etc. they sign, or rather virtually accept, digital user agreements. Digital agreements have been around since the 1990s. These agreements are written and enforced by the institutions that create these services and products. However, in certain conditions, these systems fail and these digital or service-level agreements can be breached, causing people to feel robbed. 

A recent example of this is the Robinhood scandal that occurred in mid-2021. Essentially, people came together and all wanted to buy the same stock. However, Robinhood ended up restricting buying, citing issues with volatile stock and regulatory agreements. As a result, they ended up paying $70 million dollars in fines for system outages and misleading customers. And individual customers were left feeling robbed. This was partially the result of centralization and Robinhood having full control over the platform as well as enforcing the digital agreement.

Zak Ayesh Presenting on Chainlink
and Decentralized Smart Contracts

Zak Ayesh, a developer advocate at Chainlink recently came to Duke to talk about decentralized Smart Contracts that could solve many of the problems with current centralized digital agreements and traditional paper contracts as well. 

What makes smart contracts unique is that they programmatically implement a series of if-then rules without the need for a third-party human interaction. While currently these are primarily being used on blockchains, they were actually created by computer scientist Nick Szabo in 1994. Most smart contracts now run on blockchains because it allows them to remain decentralized and transparent. If unfamiliar with blockchain refer to my previous article here. 

Smart contracts are self-executing contracts with the terms of the agreement being directly written into computer code.

Zak Ayesh

There are several benefits to decentralized contracts. The first is transparency. Because every action on a blockchain is recorded and publicly available, the enforcement of smart contracts is unavoidably built-in. Next is trust minimization and guaranteed execution. With smart contracts, there is reduced counterparty risk — that’s the probability one party involved in a transaction or agreement might default on its contractual obligation because neither party has control of the agreement’s execution or enforcement. Lastly, they are more efficient due to automation. Operating on blockchains allows for cheaper and more frictionless transactions than traditional alternatives. For instance, the complexities of cross-border remittances involving multiple jurisdictions and sets of legal compliances can be simplified through coded automation in smart contracts.

Dr. Campbell Harvey, a J. Paul Sticht Professor of International Business at Fuqua, has done considerable research on smart contracts as well, culminating in the publication of a book, DeFi and the Future of Finance which was released in the fall of 2021.

In the book, Dr. Harvey explores the role smart contracts play in decentralized finance and how Ethereum and other smart contract platforms give rise to the ability for decentralized application or dApp. Additionally, smart contracts can only exist as long as the chain or platform they live on exists. However, because these platforms are decentralized, they remove the need for a third party to mediate the agreement. Harvey quickly realized how beneficial this could be in finance, specifically decentralized finance or DeFi where third-party companies, like banks, mediate agreements at a high price.  

“Because it costs no more at an organization level to provide services to a customer with $100 or $100 million in assets, DeFi proponents believe that all meaningful financial infrastructure will be replaced by smart contracts which can provide more value to a larger group of users,” Harvey explains in the book

Beyond improving efficiency, this also creates greater accessibility to financial services. Smart contracts provide a foundation for DeFi by eliminating the middleman through publicly traceable coded agreements. However, the transition will not be completely seamless and Harvey also investigates the risks associated with smart contracts and advancements that need to be made for them to be fully scalable.

Ultimately, there is a smart contract connectivity problem. Essentially, smart contracts are unable to connect with external systems, data feeds, application programming interfaces (APIs), existing payment systems, or any other off-chain resource on their own. This is something called the Oracle Problem which Chainlink is looking to solve.

Harvey explains that when a smart contract is facilitating an exchange between two tokens, it determines the price by comparing exchange rates with another similar contract on the same chain. The other smart contract is therefore acting as a price oracle, meaning it is providing external price information. However, there are many opportunities to exploit this such as purchasing large amounts on one oracle exchange in order to alter the price and then go on to purchase even more on a different exchange in the opposite direction. This allows for capitalization on price movement by manipulating the information the oracle communicates to other smart contracts or exchanges. 

That being said, smart contracts are being used heavily, and Pratt senior Manmit Singh has been developing them since his freshman year along with some of his peers in the Duke Blockchain Lab. One of his most exciting projects involved developing smart contracts for cryptocurrency-based energy trading on the Ethereum Virtual Machine allowing for a more seamless way to develop energy units.

One example of how this could be used outside of the crypto world is insurance. Currently, when people get into a car accident it takes months or even a year to evaluate the accident and release compensation. In the future, there could be sensors placed on cars connected to smart contracts that immediately evaluate the damage and payout.

Decentralization allows us to avoid using intermediaries and simply connect people to people or people to information as opposed to first connecting people to institutions that can then connect them to something else. This also allows for fault tolerance: if one blockchain goes down, the entire system does not go down with it. Additionally, because there is no central source controlling the system, it is very difficult to gain control of thus protecting against attack resistance and collusion resistance. While risks like the oracle problem need to be further explored, the world and importance of DeFi, as well as smart contracts, is only growing.

And as Ayesh put it, “This is the future.”

Post by Anna Gotskind, Class of 2022

Duke has 38 of the World’s Most Highly-Cited Scientists

Peak achievement in the sciences isn’t measured by stopwatches or goals scored, it goes by citations – the number of times other scientists have referenced your findings in their own academic papers. A high number of citations is an indication that a particular work was influential in moving the field forward.

Nobel laureate Bob Lefkowitz made the list in two categories this year.

And the peak of this peak is the annual “Highly Cited Researchers” list produced each year by the folks at Clarivate, who run the Institute for Scientific Information. The names on this list are drawn from publications that rank in the top 1% by citations for field and publication year in the Web of Science™ citation index – the most-cited of the cited.

Duke has 38 names on the highly cited list this year — including Bob Lefkowitz twice because he’s just that good — and two colleagues at the Duke NUS Medical School in Singapore. In all, the 2021 list includes 6,602 researchers from more than 70 countries.

The ISI says that US scientists are a little less than 40 percent of the highly cited list this year – and dropping. Chinese researchers are gaining, having nearly doubled their presence on the roster in the last four years.

“The headline story is one of sizeable gains for Mainland China and a decline for the United States, particularly when you look at the trends over the last four years,” said a statement from David Pendlebury, Senior Citation Analyst at the Institute for Scientific Information. “(This reflects) a transformational rebalancing of scientific and scholarly contributions at the top level through the globalization of the research enterprise.”

Without further ado, let’s see who our champions are!

Biology and Biochemistry

Charles A. Gersbach

Robert J. Lefkowitz

Clinical Medicine

Pamela S. Douglas

Christopher Bull Granger

Adrian F. Hernandez

Manesh R.Patel

Eric D. Peterson

Cross-Field

Richard Becker

Antonio Bertoletti (NUS)

Yiran Chen

Stefano Curtarolo

Derek J. Hausenloy (NUS)

Ru-Rong Ji

Jie Liu

Jason W. Locasale

David B. Mitzi

Christopher B. Newgard

Ram Oren

David R. Smith

Heather M. Stapleton

Avner Vengosh

Mark R. Wiesner

Environment and Ecology

Emily S. Bernhardt

Geosciences

Drew T. Shindell

Immunology

Edward A. Miao

Microbiology

Barton F. Haynes

Neuroscience and Behavior

Quinn T. Ostrom

Pharmacology and Toxicology

Robert J. Lefkowitz

Plant and Animal Science

Xinnian Dong

Sheng Yang He

Philip N. Benfey

Psychiatry and Psychology

Avshalom Caspi

E. Jane Costello

Honalee Harrington

Renate M. Houts

Terrie E. Moffitt

Social Sciences

Michael J. Pencina

Bryce B. Reeve

John W. Williams

Post by Karl Bates

Discipline Makes You Free: Exploring Nigerian Militarism in the Late 20th Century

Six years after Nigeria gained its independence from Great Britain in 1960, a bloody military coup transferred power to the nation’s armed forces.

The ensuing forty-year period was marked by eight different military regimes and a Civil War, which were often demarcated by similarly violent coups that overthrew the initial Republic. Brief interludes of constitutional republics occasionally emerged, but these periods were short-lived and quickly replaced by another military government.

The eight different Heads of State under different military governments (Top row from left to right: Aguiyi-Ironsi, Gowon, Mohammed, Obasanjo. Bottom row from left to right: Buhari, Babangida, Abacha, Abubakar).

The heads of these regimes were military strongmen, soldiers who had risen through the chain of command and sought to rule the nation with near-absolute power. Samuel Fury Childs Daly (PhD), a professor in Duke’s African and African American Studies department and author of the acclaimed book A History of the Republic of Biafra: Law, Crime, and the Nigerian Civil War, sought to dive deeper into the political philosophies of these authoritarian rulers.

Daly says the writings and opinions of these autocrats often receives insufficient attention in the modern accounts of Nigerian history. The title of his lecture through the Franklin Humanities Institute, “How Soldiers Think,” attempted to address this lack of analysis by asking several important questions: What did these soldiers believe? Why did they enact the laws that they did? How did they envision Nigeria’s future?

Dr. Samuel Fury Childs Daly (PhD)

The story of Nigerian militarism, according to Daly, has its roots in the decolonization process. The soldiers and lawmakers of the later 20th century found their inspiration in one of the most famous decolonial thinkers: Frantz Fanon. Fanon’s two seminal works – Black Skin, White Masks and The Wretched of The Earth – were rooted heavily in his experience as a trained psychiatrist and a soldier for the Front de Libération National, the Algerian nationalist movement that fought against French colonial rule during the French-Algerian War (1954-1962). His advocacy for violent decolonization inspired anticolonial fury within Nigerian intellectuals and soldiers alike, leading to the widely accepted notion that military violence could be both reparative and restorative.

Fanon, in many ways, gave these soldiers a language of revolution, but, as Daly points out, many of them found his socialist politics to be too radical for Nigerian society. To the military rulers, the ideal system of governance was ascetic, masculine, and heavily disciplined.

In many ways, these soldiers sought to craft Nigeria in their own image–an image of order and self-control, a society where civilians needed to be tamed.

To create this society, the soldiers relied heavily on criminal law and the law enforcement apparatus. To them, law served as a tool of social engineering, albeit one that didn’t always work in their favor. Despite setting up a plethora of friendly judges throughout the judicial system, occasional rulings would rub military officers the wrong way. Nonetheless, they were able to exercise their heavy influence over the legislative and judicial systems to set forth programs aimed to reduce the perceived disease of chaos that plagued the Nigerian population.

One of the major initiatives Daly highlighted was the infamous War Against Indiscipline (WAI). The WAI initiated a number of often draconian programs such as the mandate to queue in an orderly manner for buses. Those who refused to form a line would be promptly whipped or beaten by an officer. Other social reforms outside of WAI centered heavily around sacrifice and control, such as the requirements for women to dress modestly and for men to stay fit; in fact, exercise was routinely used as public punishment for unruly activity.

These behavioral and punitive measures were heavily inspired by the rigid and militaristic upbringing of these autocrats, which is precisely why they were so unpopular with civilians. Daly describes several misconceptions within these leaders’ political philosophy – their treatment of politics as binary, their desire for conformity, their misconstrued knowledge of what their people want – that ultimately led to the instability of their regimes.

Through a unique combination of warped decolonization rhetoric, militaristic attitudes, and malleable jurisprudence, Nigerian political practices of the late 20th century offer a glimpse at the shortcomings of discipline as a primary political ethos. The societies formed under the military heads of state were illiberal and, contrary to the title of this article, decidedly unfree.

*the images from this article were obtained from Dr. Daly’s 2021 presentation “How Soldiers Think” through the Franklin Humanities Institute.

Post by Vibhav Nandagiri, Class of 2025

Integrating Pediatric Care in NC: Behavioral Health Perspectives

In healthcare, developing a new treatment is often half of the battle. The other half lies in delivering these treatments to those communities who need them the most. Coordinating care delivery is the goal of NC Integrated Care for Kids (InCK), an integrated pediatric service delivery and payment platform looking to serve 100,000 kids within five counties — Alamance, Orange, Durham, Granville, and Vance — in central North Carolina. The project is a collaborative effort between Duke, UNC, and the NC Department of Health and Human Services (DHHS) funded by a federal grant from the Centers for Medicare and Medicaid Services (CMS). The program’s executive director is Dr. Charlene Wong (MD, MSPH), a Duke researcher, physician, and professor who leads an interdisciplinary team of researchers and policy experts as they explore ways to reduce costs via integrating care for North Carolina youth enrolled in Medicaid and Children’s Health Insurance Program (CHIP).

The five counties that are part of NC InCK

I recently had the opportunity to speak with two of InCK’s service partners: Dr. Gary Maslow (MD, MPH) and Chris Lea (Duke ’18). Both work within the Behavioral Health group of InCK, which seeks to use behavioral health expertise through collaborative care and training providers to help support pediatric care. Maslow, a professor at the Duke Medical School, has focused heavily on child and developmental psychiatry throughout his career. Having entered medical school with a desire to work in pediatric hematology, Maslow recalls how a conversation with a mentor steered him in the direction of behavioral health. At the time, Maslow was part of the Rural Health Scholars program at Dartmouth College; while discussing his aspirations, one of his professors asked him to consider conditions outside of cancer, leading Maslow to consider chronic illness and eventually child psychiatry. “Kids have other problems,” Maslow’s professor told him.

Dr. Gary Maslow (MD, MPH)
Chris Lea (Duke ’18)

When looking at healthcare networks, especially those in rural areas in North Carolina, Maslow noticed a disaggregated service and payment network where primary care providers were not getting the necessary education to support the behavioral health needs of children. His work with Lea, a third-year medical student at Duke, has centered around looking at Medicaid data to understand provider distribution, medication prescription, and access to therapy based one’s area of residence. Lea’s path to NC InCK began as an undergraduate at Duke, where he obtained a B.S. in psychology in 2018. As he explains, mental health has been a vested interest of his for years, a passion reinforced by coursework, research at the Durham VA Medical Center, and NC InCK. He discussed the important of appropriate crisis response, specifically how to prepare families and providers in the event of pediatric behavioral health crises such as aggression or suicidality, as critical in improving behavioral health integration. These safety plans are critical both before a potential crisis and after an actual crisis occurs.

Two main goals of Maslow and Lea’s work are to increase the implementation of safety plans for at-risk youth and expand follow-up frequency in primary care settings. The focus on primary care physicians is especially critical considering the severe shortage of mental health professionals around North Carolina.

The behavioral health group is but one subset of the larger NC InCK framework. The team is led by Chelsea Swanson (MPH). Other collaborators include Dr. Richard Chung (MD), Dan Kimberg, and Ashley Saunders. NC InCK is currently in a two-year planning period, with the program’s launch date slated for 2022.

Services provided by NC InCK

A Puzzling Saga – Meet Duke Math’s Breakout Star!

When I think of crosswords, I think of young and old alike gathered around a couch, scribbling away on a freshly arrived newspaper on a clear Sunday morning. When I think of math, I think of passionate professors covered in chalk dust from a hard day’s work of etching out complicated Greek symbols and numbers on a huge blackboard. These two visions had always been comfortably separate from each other (disjoint sets, if you will) – until I met Dr. Adam Levine.

Meet Duke’s Adam Simon Levine – who shares his name with a pop star, and is a math and crossword rockstar in his own right.

Levine is an Associate Professor in the Department of Mathematics at Duke who studies low-dimensional topology, surfaces, knots and manifolds, using something called Heegaard Floer homology. But apart, from his incredible passion for his field, numerous grants and tongue-twister-esque research interests, Levine has one accomplishment that sets him apart.

He published a crossword puzzle in the New York Times on Sept. 25!

In our Zoom conversation, Levine was bright, chirpy and incredibly excited to talk about his unique love for crosswords and how he’s kept his hobby alive even under the pressures of academic life. As a teenager he loved working on puzzles like Scrabble, playing around with words and etymology, and of course, crosswords. As he grew older, he continued to be fascinated by words.

As an undergrad taking a History of Life class at Harvard, Levine learned about the the impact site of the asteroid that wiped out the dinosaurs, the Chicxulub crater. His first thought was, “That’s a fantastic word– that would make the perfect crossword entry!” His fascination with the word would stay alive for years, until it became the seed entry (the word that anchors the puzzle) for his first crossword to be published in the Times. His love for wordplay through the years is clear, from a self-composed song on Heegaard Floer homology, to a sonnet summary of his PhD thesis.

Watch Levine’s self-composed song here.

Levine continued to solve puzzles as he earned his multiple graduate degrees in mathematics, and began publishing his own puzzles a few years on his aptly named blog – Knotty Grids. Crosswords have been a fun and necessary hobby for him – a way to de-stress or take his mind off his academic work. He thinks it is an important example to set for undergraduate students hoping to pursue a career in math – to show them that it is possible to be “full human beings” and have diverse and unique hobbies, interests and a life outside of your research.

Levine often intertwines his puzzles with his primary interest. Some of his puzzles are “themed” – with “Tying Up Loose Ends” built around topological concepts, and the math-y “Indivisible” which was published in The Mathematical Intelligencer. His personal favorites, however, delve into the meta-puzzle genre with “The Queen’s Gambit” and “A Series of Unfortunate Events.”

Levine’s crossword grids are very literally inspired by his daily work with knots.

When I talked to him shortly after the NYT puzzle appeared, Levine was still visibly excited. He compared the puzzle-publishing journey to that of submitting his mathematical research to academic journals – tedious, long and not very fast-moving. Having submitted the crossword to the newspaper more than a year ago, he heard back from them early this year, at which point they began editing and working on the final publication.

As Levine spoke about the editing process, he brought up an issue that has been important to him – diversity in the puzzle world. Because most crosswords have been written by white men, clues and answers are often tilted towards what that demographic considers common knowledge, and minority and female creators have remained a very small voice. Erasure of their identities is common, and  Levine related a firsthand experience. His clue for “ROBIN” was “the first Black woman to host Jeopardy.” But it was initially edited to be a reference to the bird.

Levine says he pushed back on the parts of the puzzle that were important to him, and was glad with the final published result.

He says he was amazed by the outpouring of support and congratulations he received after the crossword came out. His parents were “really pumped,” family excited, and colleagues incredibly surprised to see his name in print (on a non-academic paper). Unfortunately, the weekend that the crossword was published, his undergraduate students were cramming for a midterm scheduled that Monday, which Levine figures might be the reason some of his crossword-fanatic students seem to have missed his big moment of glory.

In the following week, I spoke to one of Levine’s academic advisees and other Duke students passionate about puzzles, who shared an initial shock and an immediate subsequent joy in the Blue Devil puzzle representation that this publication debuted.

 While Levine has no imminent plans of writing another NYT puzzle, he continues to write for his personal blog. Hopefully, his unique journey inspires students and faculty from different fields and of varied backgrounds to contribute, create and participate, helping make his dream of a diverse puzzle world a reality.

Post by Nidhi Srivaths, Class of 2024


How To Hold a Bee and Not Get Stung

Pictured from left to right are Lindsey Weyant, Andrew McCallum, and Will Marcus.

On Saturday, September 25, the Wild Ones club hosted an insect-themed outing with Fred Nijhout, an entomology professor at Duke. We visited a pond behind the Biological Sciences Building bordered by vegetation. Apparently, the long grasses and flowers are prime habitat for insects, which are often attracted to sunny areas and edge habitat. Along with several other students, I practiced “sweeping” for insects by swishing long nets through vegetation, a delightfully satisfying activity, especially on such a gorgeous fall day.

A species of skipper feeding on a flower. According to Fred Nijhout, the best way to distinguish butterflies (including skippers) from moths is by looking for knobbed antennae, characteristic of butterflies but not moths.

Professor Nijhout says much of his research focuses on butterflies and moths, but the insect biology class he teaches has a much broader focus. So does this outing. In just a couple hours, our group finds a wide array of species.

A milkweed bug (left) and a soldier beetle, two of the species we saw on Sunday.

Many of the insects we see belong to the order Hemiptera, a group sometimes referred to as “true bugs” that includes more than 80,000 species. We find leafhoppers that jump out of our nets while we’re trying to look at them, a stilt-legged bug that moves much more gracefully on its long legs than I ever could on stilts, spittlebugs that encase themselves in foam as larvae and then metamorphose into jumping adults sometimes called froghoppers, and yet another Hemipteran with a wonderfully whimsical name (just kidding): the plant bug.

Professor Nijhout shows us a milkweed leaf teeming with aphids (also in the order Hemiptera) and ants. He explains that this is a common pairing. Aphids feed on the sap in leaf veins, which is nutrient-poor, so “they have special pumps in their guts that get rid of the water and the sugars” and concentrate the proteins. In the process, aphids secrete a sugary substance called honeydew, which attracts ants.

The honeydew excreted as a waste product by the aphids provides the ants with a valuable food source, but the relationship is mutualistic. The presence of the ants affords protection to the aphids. Symbiosis, however, isn’t the only means of avoiding predation. Some animals mimic toxic look-alikes to avoid being eaten. Our group finds brightly colored hoverflies, which resemble bees but are actually harmless flies, sipping nectar from flowers. Professor Nijhout also points out a brightly colored milkweed bug, which looks toxic because it is.

Sixteen species of hoverfly, all of which are harmless. Note that hoverflies, like all flies, have only one pair of wings, whereas bees have two.
Image from Wikipedia user Alvesgaspar (GNU Free Documentation License, Creative Commons license).

Humans, too, can be fooled by things that look dangerous but aren’t. As it turns out, even some of our most basic ideas about risk avoidance—like not playing with bees or eating strange berries—are sometimes red herrings. When we pass clusters of vibrant purple berries on a beautyberry bush, Professor Nijhout tells us they’re edible. “They’re sweet,” he says encouragingly. (I wish I could agree. They’re irresistibly beautiful, but every time I’ve tasted them, I’ve found them too tart.) And on several occasions, to the endless fascination of the Wild Ones, he catches bees with his bare hands and offers them to nearby students. Male carpenter bees (which can be identified by the patch of yellow on their faces) have no stinger, and according to Professor Nijhout, their mandibles are too weak to penetrate human skin. It’s hard not to flinch at the thought of holding an angry bee, but there’s a certain thrill to it as well. When I cup my hands around one of them, I find the sensation thoroughly pleasant, rather like a fuzzy massage. The hard part is keeping them from escaping; it doesn’t take long for the bee to slip between my hands and fly away.

Professor Nijhout in his element, about to capture a male carpenter bee (below) by hand.

The next day, I noticed several bees feeding on a flowering bush on campus. Eager to test my newfound knowledge, I leaned closer. Even when I saw the telltale yellow faces of the males, I was initially hesitant. But as I kept watching, I felt more wonder than fear. For perhaps the first time, I noticed the way their buzzy, vibrating bodies go momentarily still while they poke their heads into blossoms in search of the sweet nectar inside. Their delicate wings, blurred by motion when they fly, almost shimmer in the sunlight while they feed.

Gently, I reached out and cupped a male bee in my hands, noticing the way his tiny legs skittered across my fingers and the soft caress of his gossamer wings against my skin. When I released him, his small body lifted into the air like a fuzzy UFO.

I realize this new stick-my-face-close-to-buzzing-bees pastime could backfire, so I don’t necessarily recommend it, especially if you have a bee allergy, but if you’re going to get face-to-face with a carpenter bee, you might at least want to check the color of its face.

Damla Ozdemir, a member of the Wild Ones, with a giant cockroach in Professor Nijhout’s classroom.

If you could hold all the world’s insects in one hand and all the humans in the other, the insects would outweigh us. More than 900,000 species of insects have been discovered, and there may be millions more still unknown to science. Given their abundance and diversity, even the experts often encounter surprises.“Every year I see things I’ve never seen before,” Professor Nijhout told us. Next time you step outside, take a closer look at your six-legged company. You might be surprised by what you see.

By Sophie Cox, Class of 2025

Cemetery, Community, Classroom: Collaborating to Honor the Dead

Open Durham

The institutional neglect and indignity faced by many African Americans during and after the Jim Crow era in the South didn’t end when their lives did. In a panel hosted by the Duke Office of Durham & Community Affairs on Sept. 10, a community leader, Duke professor, and undergraduate student discussed some of the work they are doing to combat the marginalization of Durham’s deceased in Geer Cemetery, two miles from Duke’s campus. 

Debra Taylor Gonzalez-Garcia, President, Friends of Geer Cemetery

Founded on land purchased from Frederick and Polly Geer by John O’Daniel, Nelson Mitchell, and Willie Moore in 1877, Geer Cemetery is the final resting place for over 3000 of Durham’s African American citizens. As Maplewood Cemetery was segregated, from 1877 until the opening of Beechwood cemetery in 1924 Geer served as the only cemetery for the African American dead. Lacking public funding and under fire from the health department for overcrowding, Geer Cemetery closed in the 1930s and, in the absence of a plan for its continued upkeep, fell into a state of disrepair

President of Friends of Geer Cemetery Debra Taylor Gonzalez-Garcia provided a brief history of Geer Cemetery. 

The nonprofit Friends of Geer Cemetery was formed in 2003 by “concerned citizens and neighbors” and has worked to “restore the cemetery’s grounds and research its histories” under their mission statement “restore, reclaim, respect.” According to Gonzalez-Garcia, work consists of maintaining the cemetery grounds, repairing headstones, writing life stories, and advocating for recognition. 

Friends of Geer Cemetery has accomplished a lot in terms of restoration: in 2004 the cemetery was unrecognizable, with broken headstones, overgrowth, and sunken burials. Today, with the help of Keep Durham Beautiful, Preservation Durham, and other volunteers, the entire cemetery can now be easily viewed.

The organization also continues to work tirelessly toward their other objectives, reclamation and respect. By mining local records, research volunteers have created a database which includes approximately 1,651 burials, but efforts are ongoing. 

Gonzalez-Garcia expressed excitement about the organization receiving grant funding for an archaeological survey. “[The survey] will help us to map out burials, because currently, there is no map,” Gonzalez-Garcia said. “We aren’t sure where people are buried.” 

The community leader discussed how efforts to reclaim Geer Cemetery bring about questions that reckon with white supremacy in general. “We’re not told stories of the African Americans who built Durham,” Gonzalez-Garcia said. “Why do we know so much about Washington Duke, and nothing of Augustus Shepard? Why should Maplewood still exist and not Geer Cemetery?” 

Adam Rosenblatt

Associate Professor of the Practice in International Comparative Studies Adam Rosenblatt expressed his interest in how care for the dead is “bound up with human rights and social justice.” This interest is personal: he has his own graveless ancestors who disappeared in the Holocaust. He expressed his passion for educating others about “places of mourning in our midst” through “community-engaged” scholarship.

Along with Gonzalez-Garcia, Rosenblatt sponsored a Story+ program at Duke entitled Geer Cemetery: Labor, Dignity, and Practices of Freedom in an African American Burial Ground. With the help of sponsors and a graduate mentor, Duke undergraduates Nyrobi Manuel, Kerry Rork, and Huiyin Zhou researched the cemetery closely in order to “uncover the stories of ordinary citizens and add these stories back into the historic narrative about Geer.” The researchers produced three unique, interactive digital projects which will contribute to the Friends of Geer Cemetery’s online platform for education and outreach. 

Rosenblatt discussed one challenge the Story+ engaged with: What really constitutes a human subject? The IRB’s definition doesn’t include the dead; there’s no IRB protocols for researching the dead and their stories. Many archives disappear entirely, or are fragmented.

Nyrobi Manuel

Nyrobi Manuel, a Duke undergraduate, was one of Rosenblatt and Golzalez-Garcia’s mentees. Manuel took Rosenblatt’s course “Death, Burial, and Justice in the Americas” and says the course inspired her to dig deeper into African American death practices. Through the Story+, Manuel researched John C. Scarborough, who established the fifth-oldest Black-owned funeral home in the country. She produced a project entitled “Scarborough and Hargett Funeral Home: Dignified Death and Compassion in the Black Community.” 

Manuel discussed her findings. Many funeral directors became important figures in their community, and John C. Scarborough was no different. A philanthropist and important community member, he helped to establish Scarborough Nursery School, North Carolina’s oldest licensed nursery school.

What’s always drawn Gonzalez-Garcia to Geer Cemetery is its “quiet beauty” and sense of connection. Though her ancestors are buried in Virginia, where she’s from, Geer Cemetery seeks to tell stories of African Americans through “emancipation and reconstruction: throughout history.” Geer is special because it seeks to tell the story of her “blood relatives” while also celebrating the history of Durham, which, she said fondly, is “my community now.”

A New Algorithm for “In-Betweening” images applied to Covid, Aging and Continental Drift

Collaborating with a colleague in Shanghai, we recently published an article that explains the mathematical concept of ‘in-betweening,’in images – calculating intermediate stages of changes in appearance from one image to the next.

Our equilibrium-driven deformation algorithm (EDDA) was used to demonstrate three difficult tasks of ‘in-betweening’ images: Facial aging, coronavirus spread in the lungs, and continental drift.

Part I. Understanding Pneumonia Invasion and Retreat in COVID-19

The pandemic has influenced the entire world and taken away nearly 3 million lives to date. If a person were unlucky enough to contract the virus and COVID-19, one way to diagnose them is to carry out CT scans of their lungs to visualize the damage caused by pneumonia.

However, it is impossible to monitor the patient all the time using CT scans. Thus, the invading process is usually invisible for doctors and researchers.

To solve this difficulty, we developed a mathematical algorithm which relies on only two CT scans to simulate the pneumonia invasion process caused by COVID-19.

We compared a series of CT scans of a Chinese patient taken at different times. This patient had severe pneumonia caused by COVID-19 but recovered after a successful treatment. Our simulation clearly revealed the pneumonia invasion process in the patient’s lungs and the fading away process after the treatment.

Our simulation results also identify several significant areas in which the patient’s lungs are more vulnerable to the virus and other areas in which the lungs have better response to the treatment. Those areas were perfectly consistent with the medical analysis based on this patient’s actual, real-time CT scan images. The consistency of our results indicates the value of the method.

The COVID-19 pneumonia invading (upper panel) and fading away (lower panel) process from the data-driven simulations. Red circles indicate four significant areas in which the patient’s lungs were more vulnerable to the pneumonia and blue circles indicate two significant areas in which the patient’s lungs had better response to the treatment. (Image credit: Gao et al., 2021)
We also applied this algorithm to simulate human facial changes over time, in which the aging processes for different parts of a woman’s face were automatically created by the algorithm with high resolution. (Image credit: Gao et al., 2021. Video)

Part II. Solving the Puzzle of Continental Drift

It has always been mysterious how the continents we know evolved and formed from the ancient single supercontinent, Pangaea. But then German polar researcher Alfred Wegener proposed the continental drift hypothesis in the early 20th century. Although many geologists argued about his hypothesis initially, more sound evidence such as continental structures, fossils and the magnetic polarity of rocks has supported Wegener’s proposition.

Our data-driven algorithm has been applied to simulate the possible evolution process of continents from Pangaea period.

The underlying forces driving continental drift were determined by the equilibrium status of the continents on the current planet. In order to describe the edges that divide the land to create oceans, we proposed a delicate thresholding scheme.

The formation and deformation for different continents is clearly revealed in our simulation. For example, the ‘drift’ of the Antarctic continent from Africa can be seen happening. This exciting simulation presents a quick and obvious way for geologists to establish more possible lines of inquiry about how continents can drift from one status to another, just based on the initial and equilibrium continental status. Combined with other technological advances, this data-driven method may provide a path to solve Wegener’s puzzle of continental drift.

The theory of continental drift reconciled similar fossil plants and animals now found on widely separated continents. The southern part after Pangaea breaks (Gondwana) is shown here evidence of Wegener’s theory. (Image credit: United States Geological Survey)
The continental drift process of the data-driven simulations. Black arrow indicates the formation of the Antarctic. (Image credit: Gao et al., 2021)

The study was supported by the Department of Mathematics and Physics, Duke University.

CITATION: “Inbetweening auto-animation via Fokker-Planck dynamics and thresholding,” Yuan Gao, Guangzhen Jin & Jian-Guo Liu. Inverse Problems and Imaging, February, 2021, DOI: 10.3934/ipi.2021016. Online: http://www.aimsciences.org/article/doi/10.3934/ipi.2021016

Yuan Gao

Yuan Gao is the William W. Elliot Assistant Research Professor in the department of mathematics, Trinity College of Arts & Sciences.

Jian-Guo Liu is a Professor in the departments of mathematics and physics, Trinity College of Arts & Sciences.

Jian-Guo Liu

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