Duke Research Blog

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

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Does aging make our brains less efficient?

We are an aging population. Demographic projections predict the largest population growth will be in the oldest age group – one study predicted a doubling of people age 65 and over between 2012 and 2050. Understanding aging and prolonging healthy years is thus becoming increasingly important.

Michele Diaz and her team explore the effects of aging on cognition.

For Michele Diaz, PhD, of Pennsylvania State University, understanding aging is most important in the context of cognition. She’s a former Duke faculty member who visited campus recently to update us on her work.

Diaz said the relationship between aging and how we think is much more nuanced than the usual stereotype of a steady cognitive decline with age.

Research has found that change in cognition with age cannot be explained as a simple decline: while older people tend to decline with fluid intelligence, or information processing, they maintain crystallized intelligence, or knowledge.

Diaz’s work explores the relationship between aging and language. Aging in the context of language shows an interesting phenomenon: older people have more diverse vocabularies, but may take longer to produce these words. In other words, as people age, they continue to learn more words but have a more difficult time retrieving them, leading to a more frequent tip-of-the-tongue experience.

In order to understand the brain activation patterns associated with such changes, Diaz conducted a study where participants of varying ages were asked to name objects depicted in images while undergoing fMRI scanning. As expected, both groups showed less accuracy in naming of less common objects, and the older adult group showed a slightly lower naming accuracy than the younger.

Additionally, Diaz found that the approach older adults take to solving more difficult tasks may be different from younger adults: in younger adults, less common objects elicited an increase in activation, while older adults showed less activation for these more difficult tasks.

Additionally, an increase in activation was associated with a decrease in accuracy. Taken together, these results show that younger and older adults rely on different regions of the brain when presented with difficult tasks, and that the approach younger adults take is more efficient.

In another study, Diaz and her team explored picture recognition of objects of varying semantic and phonological neighborhood density. Rather than manipulation of how common the objects presented in the images are, this approach looks at networks of words based on whether they sound similar or have similar meanings. Words that have denser networks, or more similar sounding or meaning words, should be easier to recognize.

An example of a dense (left) and sparse (right) phonological neighborhood. Words with a greater number of similar sounding or meaning words should be more easily recognized. Image courtesy of Vitevitch, Ercal, and Adagarla, Frontiers in Psychology, 2011.

With this framework, Diaz found no age effect on recognition ability for differences in semantic or phonological neighborhood density. These results suggest that adults may experience stability in their ability to process phonological and semantic characteristics as they age.

Teasing out these patterns of decline and stability in cognitive function is just one part of understanding aging. Research like Diaz’s will only prove to be more important to improve care of such a growing demographic group as our population ages.

Post by undergraduate blogger Sarah Haurin

Post by undergraduate blogger Sarah Haurin

On ‘Things We Already Know,’ Checklists and Mindfulness

I recently spoke to the Academic Council about my new role overseeing Duke’s entire research enterprise – medical and campus –  and I reiterated for them the messages in my first blog post: that all of us should take part in the quality and rigor of Duke’s research efforts and that everyone should participate in activities like Responsible Conduct of Research (RCR) training and other activities that will help us to improve.

Not all the faculty are persuaded, I soon learned.

“I read your recent blog post about quality. Clearly that was not meant for me,” one senior faculty member said to me. He suggested that my reminding the community of such matters was beneath him, and probably beneath many other faculty. “Of course we treat people with respect! Of course we always do research the right way!”

In response, let me share with you an important lesson from a book I read recently, “The Checklist Manifesto,” by Atul Gawande. He’s a general and endocrine surgeon at Brigham and Women’s Hospital in Boston who advocates the use of checklists for surgeons, just as pilots and space programs have used.

Dr. Atul Gawande

Checklists impose structure, they force us to think more slowly and carefully, and to systematically address specific questions of relevance to the mission, even if it’s a procedure we’ve done countless times before. Pilots and astronauts aren’t insulted by them.

At the end of his book, Gawande writes about his personal use of checklists in his surgical practice and a very important lesson he learned by using them.

When he first started thinking about checklists, Gawande thought it was an interesting subject, and that it was highly relevant to the average surgeon. However, with respect to himself, a top-flight surgeon, a former Rhodes Scholar and a MacArthur Fellow, he felt the exercise was probably redundant.

But since he had written and spoken so much about checklists, Gawande always went through the motions, just to avoid looking like a hypocrite. That is, until a particular surgery humbled and changed his perspective on checklists forever.

Gawande was about to perform a surgery, and the head nurse was going down the list of items needed for this particular procedure. All items checked off as expected until they came to the need for a substantial supply of blood in case of a rare complication that could cause severe bleeding.

This item surely was added after a prior disaster and a root-cause analysis that refined the checklist for this type of surgery. But as they went down the checklist, the extra blood was absent. So the team quickly got the blood, and the surgery commenced.

To Gawande’s horror, this particular surgery triggered that rare complication. But because they had the substantial supply of extra blood on hand, the surgical team was able – with great effort — to save the patient’s life.

Gawande says he was chastened by this experience. Without attention to the checklist, this patient would have died on the table.

But academic research isn’t anything like flying a plane or opening an abdomen, or is it? I think the stakes for university research are very high. Duke just settled a case related to research misconduct that cost the university more than $100 million, and damaged our reputation. It might have been prevented.

Pilots routinely use checklists before and during flight.

We have a responsibility to be good stewards of the more than $1 billion in annual funding that allows us to do this important work. The organizations that entrust us with those resources (often the federal government) are counting on us to use those resources well, and to engage in research of the highest quality. The stakes are high, and so should be our responsibilities.

While they aren’t a perfect analogue to things like RCR training, safety checklists address predictable human fallibility, which is often a result of thinking instinctually rather than carefully. RCR training, conflict of interest forms, institutional review boards and other research controls seek to address issues in the same way, by identifying problems that have come up in the past at Duke or other institutions and trying to prevent these lessons from having to be learned again (analogous to the need for extra blood).

I also think it’s important that another key component of checklists is cultural: Anyone on the surgical team is allowed to question anything before or during the surgery. This means that a junior nurse on the team can challenge the lead surgeon if they see something that is in conflict with best practice or the checklist. If you see something, say something.

Anyone at Duke who sees behavior that challenges the values connected to the principles of our checklists – conflict of interest, institutional review board, responsible conduct of research — has the right, and the responsibility, to say something.

Inviting faculty, trainees and staff to engage with training does not mean we feel our people are unaware of these issues. It does not mean we feel that Duke researchers lack integrity. It is just that we are all very busy and focused on many things, and we are human.

I’m asking all of us to slow down for a moment, and to remind ourselves of our responsibility to ourselves, to the broader Duke community, and to our research sponsors. We want to set a tone and a culture that will help all of us push the Duke research enterprise to even higher levels of excellence.

Post by Larry Carin, Vice President for Research

Legendary Paleontologist Richard Leakey Visits Duke

Hoping to catch up with an old friend who is a professor at Duke, Richard Leakey accepted an invitation to speak at the university on Oct. 22, though he “gave up public speaking to a large extent many years ago.”

Richard E. Leakey visited Duke on Oct. 22, 2019.

Leakey, age 74, is a world-renowned pioneer in Paleoanthropology – the study of the human fossil record – and is also well-known for his involvement in Kenyan politics and lifelong efforts towards conservation and wildlife protection. Once, he famously burned twelve tons of elephant tusks that were confiscated from poachers, which gathered international attention and helped usher in a global ban on the ivory trade.

Leakey came to paleontology by heredity. He is one of an entire family of Paleo-pioneers. His mother, Mary, discovered a skull in Africa that was dated to 1.75 million years ago (MYA) in 1960. Leakey said that this “electrified interest in the origin story” – that is, the human origin story. When his father, Louis, showed that the “quite clever” ancient tools he had discovered were made around 1.75 MYA, the original idea that human origins began outside of Africa began to change.

Leakey said the British people were hoping that “if we had evolved … let it happen in England” and if not England, then Asia, but this was not to be the case. At first, Louis Leakey was ostracized because of his work and discoveries of human origins in Africa. This helped steer Richard away from academics because of the fights that he saw his father endure.

Leakey’s famous 1984 Kenyan discovery, “Turkana Boy,” a 1.5 million-year-old, nearly-complete specimen of Homo erectus. (Wikipedia)

Successfully achieving his self-described ambition to not finish high school, Richard Leakey was thrown out of school at age 16. Yet today he is accredited with many awards, has written at least eight books, and has advanced the Leakey family legacy of discovery. From 1968 to the present day, he and fellow workers have discovered enormous numbers of fossils of our ancestors along the East and West shores of Lake Turkana in Kenya, which have an age span from 4.5 MYA to our very recent ancestors, which Leakey calls “fossil us.”

Leakey described for the Duke audience in an overflowing auditorium at the Nasher Museum a scenario he facilitated with colleagues and students.

He had taken a group to a camp site to talk about evolution and asked them to perform some tasks. First, they were charged to make tools from stone. The following day, they were led to a freshly slaughtered goat. Leakey told his pupils to butcher the goat and remove the flesh from its carcass.

After several hours watching the individuals try to pull at the goat with their hands to no avail, Leakey suggested that they might use their new stone tools. So they did, but they still could not get through the animal’s tough hide, even with a blade.

He said that during human evolution, our imagination was turned on genetically and this gave early humans the “capability to think of things that weren’t.” There is lots of work to be done studying an ancient period over 3.5 million years that Leakey says lends itself to “early ancestry of speech, imagination, [and] cooperation.” He is hopeful for the knowledge and new understandings that will come from investigation of this period. 

“Why not ask someone to help you?” Leakey prompted again, and within an hour, nothing was left of the goat. The exercise demonstrated that though other monkeys and apes use stone, it is the human’s vocal communication and sense of working together that sets us apart, says Leakey.     

Leakey’s current project is a “mega-museum” to “cerebrate and celebrate the story of the African origin.” The origin story which his parents first provided crucial evidence for is hugely important to the African continent and to the people of Africa and because we have “desecrated our motherland,” he said. Leakey wants the museum to highlight stages of evolution, genetics, climate, ecology, other species, and extinctions.

An architectural rendering of Ngaren: The Museum of Humankind to be built near Nairobi. (Studio Libeskind )

Before moving into the panel and Q&A portion of his talk, which was moderated by Duke professors Steven Churchill and Anne Yoder, Leakey prompted the audience to think about climate change, asking why we do not think we need to save ourselves. If we die, then other species go with us.

“Don’t for a minute think that climate change isn’t a real crisis that we’re in together,” Leakey said, earning a round of applause.

Post by Cydney Livingston

Meet the New Blogger: Irene Park

Hi! My name is Irene Park. I’m currently a sophomore at Duke, but I was born and raised in the D.C. area: home to NIH, NASA, the Smithsonian, and countless other major research complexes. I suppose my proximity to all these different knowledge bases must have influenced my current self in some way, as I’ve got a lot of multi-dimensional ideas free-floating through my mind.

At the top of Montserrat in Barcelona, Spain!

In my free time, catch me looking up cheap flights across the world, staring out the window at nothing in particular, or trying to figure out how to magically save the Amazon. And as you might expect, I’m still relatively undecided about my major simply because I feel that there’s just too much in this world to learn. Picking one specialized area is a bit daunting for me.

But what I do know is that I love stories – both hearing and telling. At age 11, I made a whole blog dedicated to chronicling what I found to be my sister’s strange K-pop obsession. That phase of her life was rather short-lived, however, and eventually I better realized my interest in journalism. I became a writer and editor for my high school newspaper and editor-in-chief of my county one. I became a film buff as well, building a portfolio that included several award-winning shorts.

In general, what I’ve learned through my last few years of storytelling is that while research is typically considered purely objective knowledge, it’s nothing without its “softer” side. Virtually everything can change depending on how a subject is framed through words, sound, or visual media. Being able to effectively communicate – whether informatively, editorially, or both – is and has always been an immensely important task.

One of the many pictures taken while “working on a film” with my group.

That’s something I’d like to build upon during my time with the Duke Research Blog: being able to turn data into words, words into sentences, and sentences into ideas. I find historical, environmental, sociological and anthropological research especially interesting, but those are already some very long terms with highly complex concepts that desire a whole lot of unpacking.

Hopefully I’ll be able to do some of that here. I might also go out on a limb and hope that my experiences at Duke Research Blog could potentially help me decide on a major, but I’m guessing all that interesting new information will just make me more confused. But who ever said that was necessarily a bad thing?

A photo of my friend and me (R) trying to figure out the inner workings of my brain.

Predicting sleep quality with the brain

Modeling functional connectivity allows researchers to compare brain activation to behavioral outcomes. Image: Chu, Parhi, & Lenglet, Nature, 2018.

For undergraduates, sleep can be as elusive as it is important. For undergraduate researcher Katie Freedy, Trinity ’20, understanding sleep is even more important because she works in Ahmad Hariri’s Lab of Neurogenetics.

After taking a psychopharmacology class while studying abroad in Copenhagen, Freedy became interested in the default mode network, a brain network implicated in autobiographical thought, self-representation and depression. Upon returning to her lab at Duke, Freedy wanted to explore the interaction between brain regions like the default mode network with sleep and depression.

Freedy’s project uses data from the Duke Neurogenetics Study, a study that collected data on brain scans, anxiety, depression, and sleep in 1,300 Duke undergraduates. While previous research has found connections between brain connectivity, sleep, and depression, Freedy was interested in a novel approach.

Connectome predictive modeling (CPM) is a statistical technique that uses fMRI data to create models for connections within the brain. In the case of Freedy’s project, the model takes in data on resting state and task-based scans to model intrinsic functional connectivity. Functional connectivity is mapped as a relationship between the activation of two different parts of the brain during a specific task. By looking at both resting state and task-based scans, Freedy’s models can create a broader picture of connectivity.

To build the best model, a procedure is repeated for each subject where a single subject’s data is left out of the model. Once the model is constructed, its validity is tested by taking the brain scan data of the left-out subject and assessing how well the model predicts that subject’s other data. Repeating this for every subject trains the model to make the most generally applicable but accurate predictions of behavioral data based on brain connectivity.

Freedy presented the preliminary results from her model this past summer at the BioCORE Symposium as a Summer Neuroscience Program fellow. The preliminary results showed that patterns of brain connectivity were able to predict overall sleep quality. With additional analyses, Freedy is eager to explore which specific patterns of connectivity can predict sleep quality, and how this is mediated by depression.

Freedy presented the preliminary results of her project at Duke’s BioCORE Symposium.

Understanding the links between brain connectivity, sleep, and depression is of specific importance to the often sleep-deprived undergraduates.

“Using data from Duke students makes it directly related to our lives and important to those around me,” Freedy says. “With the field of neuroscience, there is so much we still don’t know, so any effort in neuroscience to directly tease out what is happening is important.”

Post by undergraduate blogger Sarah Haurin
Post by undergraduate blogger Sarah Haurin

Beyond Classroom Walls: Research as an Undergrad

“Science is slow,” says Duke undergraduate Jaan Nandwani. That’s one of the takeaways from her first experience with scientific research. For Nandwani, being part of a supportive lab makes it all worthwhile. But we’re getting ahead of ourselves. This statement needs context.

Nandwani, a prehealth sophomore, currently conducts research in the lab of neurologist Nicole Calakos, MD, PhD. The Calakos lab is focused on synaptic plasticity: changes that occur at the communication junctions between nerve cells in the brain. The lab researches how the brain responds to changes in experience. They also investigate the mechanistic mishaps that can occur with certain neurological conditions.

A neuron from a mouse brain. From Wikimedia Commons.

As a continuation of an 8-week summer research program she participated in earlier this year, Nandwani has been studying dystonia, a brain disorder that causes uncontrollable muscle contractions. She’s using western blot analysis to determine if the activity of a protein called eIF2α is dysregulated in the brain tissue of mice with dystonia-like symptoms, compared with their normal littermates. It is currently unclear if and when targeting the eIF2 signaling pathway can improve dystonia, as well as where in the brain “selective vulnerability” to the signaling occurs. If Nandwani is able to identify a specific region or time point “in which the pathway’s dysregulation is most predominant,” more effective drug therapy and pharmacological interventions can be used to treat the disorder. 

Outside of her particular project, Nandwani attends lab meetings, learning from and contributing to the greater Calakos lab community. Scientific work is highly collaborative and Nandwani’s experience is testament to that. Along with providing feedback to her own presentations in meetings and answering any questions she may have, Nandwani’s fellow labmates are always eager to discuss their projects with her, give her advice on her own work, and have helped her “develop a passion for what [she is] studying.” They’ve also helped her learn new and improved ways to conduct the western blot process that is so integral to her work. Though she admits it is tedious, Nandwani said that she enjoys being able to implement better techniques each time she conducts the procedure. She also says she is thankful to be surrounded by such a supportive lab environment.

It might seem hard to believe granted the scope and potential impacts of her work, but this is Nandwani’s first experience with research in a lab. She knew when coming to Duke that she wanted to get involved with research, but she says that her experience has surpassed any expectations she had – by far. Though she doesn’t necessarily foresee continuation of research in the form of a career and is more fascinated by clinical applications of scientific research, the experience cannot be replicated within a classroom setting. Beyond the technical skills that Nandwani has developed, she says that the important and valuable mentoring relationships she has gained simply couldn’t be obtained otherwise.

Duke undergraduate Jaan Nandwani doing research in the Calakos lab.

Nandwani hopes to continue in the Calakos lab for the remainder of her time at Duke – that’s two and a half more years. Though she will work on different projects, the quest to pose and answer scientific questions is endless – and as Nandwani said, science is slow. The scientific process of research takes dedication, curiosity, collaboration, failure, and a continued urge to grow. The scientific process of research takes time, and lots of it. Of course the results are “super exciting,” Nandwani says, but it is the experience of being part of such an amazing group of scholars and scientists that she values the most.

By Cydney Livingston

Meet Cydney Livingston: An Inquisitive Sophomore and Our Newest Blogger

My name is Cydney Livingston – Cydney with a C. I was born and raised in a rural part of North Carolina and retain my roots in the southern drawl of my voice. Though I haven’t declared yet, I am a sophomore at Duke pursuing a degree in both biology and history. And no, I am not a pre-health student. But at one point I certainly thought I might be. It was my first biomedical class in high school that truly spiked my interest in the magical (though actually very proven and not make-believe at all) world of science. I dropped my dream of going into marketing and knew then that in some capacity I would spend my life dedicated to the discipline of science.

Science endlessly answers and provokes questions of why and how. This is satisfying for someone as desperately curious about the world as I am, albeit equally frustrating at times. I was initially infatuated with how and why the human body functions as it does. I pushed myself to understand intricate details leading to the makeup, to the breakdown, to the human body as a whole. However, at some point following interests in pharmaceutical drug development and epidemiology (probably after reading Evolving Ourselves and Sapiens), I became deeply perplexed by evolution and ecology instead. I love humans, but I love other animals in their many shapes and sizes too. I also really love nature and want to be honest with myself about the things that make me the happiest. Social structures and behaviors, adaptation to environment, and conservation are a few things that really excite me right now.

I can give no specifics about my career projections – and trust me when I say many people have asked – but there is a high probability I will be performing research to quench the thirst I have for comprehending and unraveling the mysteries of the biological state of our world, its interactions, how we got to this point, and what our future may hold.

My love for science parallels that of my love for writing – which aids my frequent self-reflection, inquisitions, and creative works. In addition to writing for The Muse at Duke, I maintain a journal and extensions of my brain live in word documents tucked away in folders on my computer. Staying true to my passions, as well as to my deep desire for connecting with and learning from others, I sought out a position writing for the Duke Research Blog. Through this work I will grow as a scholar, have the chance to meet some of the most brilliant minds, and ultimately be able to give those who read my blogs a glimpse into the realm of research – a realm which alters lives, offers cognizance, and propels our societies in new directions each and every day.

By Cydney Livingston

From Jails to Detention Centers: a Disconcerting Immigration History

The political climate for the past ten years has been anything but calm, and central to political struggles in D.C. and elsewhere has been the ethical issues surrounding immigrant detention. But for Brianna Nofil (T ‘12), there has never been a better time to research the questions that intrigue her the most.  

A native of South Florida, Nofil has felt the undercurrent of immigration tensions throughout her life as a resident of a region with a large population of immigrants. Central to this tension was Krome Detention Center — a looming, overpowering presence in her community. Krome, which was a missile testing facility for most of 20th century, has only recently been converted to an institution to house detained immigrants. Krome had always been there, but exactly what its existence meant in her hometown was not usually acknowledged, and as Nofil remarked, “There was a reason people living there had a hazy understanding of what was going on.” 

While at Duke, Nofil, who double majored in history and public policy studies with a minor in education, let her experiences growing up lead her to a senior thesis on the history and privatization of U.S. immigration detention — which, according to Duke history professor Gunther Peck, was nothing less than “stunning.” In a round-table forum on October 1, Nofil delved deeper into her central academic interests — of which she has written about in publications such as Time and Atlas Obscura — as well as her current studies as a doctoral candidate at Columbia University.

Jose A. Iglesias for the Miami Herald

Coming to Duke, Nofil used the resources and classes in the history department to answer two chief questions: what power structures were in place to confirm an institution like Krome’s significance in the community? And where exactly did this power come from?  

These questions lead her to her current focus at Columbia, which is the history of immigrant detention centers in the 20th century. Her main argument? “U.S immigration has always really relied on jails.” 

By the early 1900s, immigration was taking hold as a major historical event in the U.S and the federal government took its chances on what it saw as the perfect solution — let local communities handle immigration, and thus control what could (and eventually would become) a growing problem. This led to a network of contracts in the 20th century that paid sheriffs of small, lower-income towns all over America a nightly rate to “board” immigrants in jails. 

One case study, as Nofil points out, centered around Chinese immigrants in the early 1900s who came to northern New York from Canada. They were held in local jails all throughout the county while their cases were processed, and communities see the booming immigrant detention business as net-positive for the community. Within mere months, these Chinese jails had created an arms race of sorts. Communities competed and clamored for more contracts from the federal government as they saw incomes in their town continue to grow. 

It’s easy to see the moral dilemma of profiting off of detaining immigrants, but what is even more concerning is why the federal government pawned off a federal responsibility to communities, thus ensuring a lack of standardization in immigrant treatment across the country. So while there was relative support surrounding the business, unease soon began to emerge. As quota laws and anti-trafficking measures were created, Canadian and European immigrants also made their way over to the U.S, prompting foreign countries to finally notice  — and ask — whether communities utilizing prisons as detention centers was ethically sound. Newspapers around this time started publishing op-eds and editorials, and soon a resistance against profiting off of jailing immigrants cropped up — something Nofil adds is “inspiring” to see, especially in the context of our own times. 

The perpetual failure of jails has allowed immigration in the modern day to position big detention centers as a humane alternative. But what does that mean for immigration detention today? As Nofil posits, early forms of resistance are inspiring because it assures us that jailing immigrants was always questioned by communities, even at that time. Communities were capable of distinguishing right from wrong, even amidst the issue of immigration where the makeup and economy of their communities were at risk of changing. As the conversation concluded, one central theme seemed to stand out — that to understand the consequences of immigration detention centers, we must look to the past to see how detention started, and only by understanding the origins can we work toward a better solution. 

By Meghna Datta
By Meghna Datta

Vaping: Crisis or Lost Opportunity?

Wikimedia Commons

Whether you’re doing vape tricks for YouTube views or kicking yourself for not realizing that “USB” was actually your teenager’s Juul, you know vaping is all the rage right now. You probably also know that President Trump has called on the FDA to ban all flavored e-cigarettes to combat youth vaping. This comes in reaction to the mysterious lung illness that has affected 1,080 people to date. 18 of them have died.

At Duke Law School’s “Vaping: Crisis or Lost Opportunity” panel last Wednesday, three experts shared their views. 

Jed Rose, a professor of psychiatry and behavioral sciences and director of the Duke Center for Smoking Cessation, has worked in tobacco research since 1979, focusing on smoking cessation and helping pioneer the nicotine patch. Rose also directs Duke’s Center for Smoking Cessation.

According to Rose, e-cigarettes are more effective than traditional Nicotine Replacement Therapy (NRT). A recent study found that e-cigarettes were approximately twice as effective as the state-of-the-art NRT in getting smokers to quit combustible cigarettes (CCs). This makes sense because smokers are addicted to the action of puffing, so a smoking cessation tool that involves inhaling will be more successful than one that does not, like the patch.

Rose also took issue with the labeling of the current situation surrounding vaping as an “epidemic.” He called it a “crisis of exaggeration,” then contrasted the 18 deaths from vaping to the 450 annual deaths from Tylenol poisoning

Even in the “pessimistic scenario,” where e-cigarettes turn out to be far more harmful than expected, Rose said deaths are still averted by replacing cigarettes with e-cigarettes. 

The enemy, Rose argued, is “disease and death, not corporations”, like the infamous (and under-fire) Juul. 

James Davis, MD, an internal medicine physician and medical director for the Center for Smoking Cessation, works directly with patients who suffer from addiction. His research focuses on developing new drug treatments for smoking cessation. Davis also spearheads the Duke Smoke-Free Policy Initiative.

Davis began by calling for humility when using statistics regarding e-cigarette health impacts, as long-term data is obviously not yet available. 

Davis did present some known drawbacks of e-cigarettes, though, stating that e-cigarettes are similarly addictive compared to conventional cigarettes, and that a whopping 21% of high school students and 5% of middle school students use e-cigarettes. Davis also contended that “When you quit CCs with e-cigarettes, you are merely transferring your addiction to e-cigarettes. Eighty-two percent [of test subjects who used e-cigarettes for smoking cessation] were still using after a year.” 

However, according to Davis, there is a flipside. 

Similar to Rose, Davis looked to the “potential for harm reduction” — e-cigarettes’ morbidity is projected to be only 5-10% that of CCs. If the main priority is to get smokers off CC, Davis argues e-cigarettes are important: 30-35% of CC smokers say they would use an e-cigarette to quit smoking, where only 13% would use a nicotine patch. 

Furthermore, Davis questioned whether the mysterious lung disease is attributable to e-cigarettes themselves — a recent study found that 80% of a sample of afflicted subjects had used (often black-market) THC products as well.

Lauren Pacek, an assistant professor in psychiatry and behavioral sciences at Duke, examines smoking in the context of addiction and decision-making.

Pacek stated that flavored electronic nicotine delivery systems (ENDS) are important to youth: 61-95% of current youth ENDS users use flavored products, and 84% of young users say they would not use the products without flavors. So, banning flavored ENDS would ostensibly reduce young adults’ use, potentially keeping them off nicotine entirely.

However, Pacek pointed to the importance of flavors for adult users too: the ones that are purportedly using ENDS not for recreation or social status (as young people have been known to do), but for smoking cessation. Many former CC smokers report that flavored ENDS were important for their cessation. By banning flavored ENDS, the products look less appealing, and smokers are more likely to return to much more harmful cigarettes.  

So where do we go from here? 

Pacek did not take a concrete stance, but said her “take-home message” was that policymakers need to consider the impact of the ban on the non-target population, those earnest cigarette smokers looking to quit, or at least turn to a less harmful alternative. 

Rose also did not offer a way forward, but made clear that he does not support the FDA’s impending ban on flavored e-cigarettes and thinks the hysteria around vaping is mostly unfounded.

Davis did not suggest a course of action for the US, but as leader of Duke’s Smoke-Free Policy Initiative, he certainly suggested a course of action for Duke. The Initiative prohibits combustible forms of tobacco at Duke, but does not (yet) prohibit e-cigarettes. 

By Zella Hanson

These Microbes ‘Eat’ Electrons for Energy

The human body is populated by a greater number of microbes than its own cells. These microbes survive using metabolic pathways that vary drastically from humans’.

Arpita Bose’s research explores the metabolism of microorganisms.

Arpita Bose, PhD, of Washington University in St. Louis, is interested in understanding the metabolism of these ubiquitous microorganisms, and putting that knowledge to use to address the energy crisis and other applications.

Photoferrotrophic organisms use light and electrons from the environment as an energy source

One of the biggest research questions for her lab involves understanding photoferrotrophy, or using light and electrons from an external source for carbon fixation. Much of the source of energy humans consume comes from carbon fixation in phototrophic organisms like plants. Carbon fixation involves using energy from light to fuel the production of sugars that we then consume for energy.

Before Bose began her research, scientists had found that some microbes interact with electricity in their environments, even donating electrons to the environment. Bose hypothesized that the reverse could also be true and sought to show that some organisms can also accept electrons from metal oxides in their environments. Using a bacterial strain called Rhodopseudomonas palustris TIE-1 (TIE-1), Bose identified this process called extracellular electron uptake (EEU).

After showing that some microorganisms can take in electrons from their surroundings and identifying a collection of genes that code for this ability, Bose found that this ability was dependent on whether a light source was also present. Without the presence of light, these organisms lost 70% of their ability to take in electrons.   

Because the organisms Bose was studying can rely on light as a source of energy, Bose hypothesized that this dependence on light for electron uptake could signify a function of the electrons in photosynthesis.  With subsequent studies, Bose’s team found that these electrons the microorganisms were taking were entering their photosystem.

To show that the electrons were playing a role in carbon fixation, Bose and her team looked at the activity of an enzyme called RuBisCo, which plays an integral role in converting carbon dioxide into sugars that can be broken down for energy. They found that RuBisCo was most strongly expressed and active when EEU was occurring, and that, without RuBisCo present, these organisms lost their ability to take in electrons. This finding suggests that organisms like TIE-1 are able to take in electrons from their environment and use them in conjunction with light energy to synthesize molecules for energy sources.  

In addition to broadening our understanding of the great diversity in metabolisms, Bose’s research has profound implications in sustainability. These microbes have the potential to play an integral role in clean energy generation.

Post by undergraduate blogger Sarah Haurin
Post by undergraduate blogger Sarah Haurin

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