Programs to fight obesity can exacerbate eating disorders if they put too much emphasis on weight rather than exercise and healthy eating, said experts in a panel discussion at the Harvard T.H. Chan School of Public Health.

The conundrum highlights the complexity of addressing eating disorders such as bulimia, anorexia, and binge eating at time when recognition is low, screening inadequate, insurance coverage sketchy, and fighting obesity has become a public health priority, the panelists said.

“Some obesity programs are backfiring because of their focus on weight and on the scale,” said Claire Mysko, chief executive officer of the National Eating Disorders Association. “These [eating disorders] are serious public health issues, woefully misunderstood, underfunded, and often untreated.”

Some 30 million Americans have diagnosed eating disorders and many more are undiagnosed, said Alison Field, chair of epidemiology at Brown University and head of the Growing Up Today study, which follows 17,000 boys and girls age 9 to 14.

The weight-obsessed teenage girl of stereotype is just the tip of the iceberg, Field said. Eating disorders are also an issue with boys, though the details can differ — an obsession with low body fat, the perfect physique, and washboard abs. Eating disorders affect people of all ages, walks of life, and ethnic and racial groups.

Joining Field and Mysko for “Eating Disorders, Mental Health, and Body Image,” were S. Bryn Austin, a professor of social and behavioral sciences at the Harvard Chan School and director of the Strategic Training Initiative for Prevention of Eating Disorders, and Thomas Weigel, an instructor in psychiatry at Harvard Medical School and associate medical director for McLean Hospital’s Klarman Eating Disorders Center. The event was moderated by Carol Hills, senior producer and reporter for PRI’s “The World.”

Eating disorders fall into three main categories. In anorexia, the patient eats very little; bulimia involves binge eating followed by a compensating behavior such as vomiting; and a binge eating disorder — the most common of the three — includes binge eating without the compensating behavior.

There are many people who may not precisely fit those criteria but for whom thoughts about food and body weight are disruptive, Mysko said. Education on the subject is poor enough that people often call the National Eating Disorders Association helpline and say, “I don’t know if I qualify,” she said.

A disposition for an eating disorder can be inherited, the panelists said. Those suffering from eating disorders are often experiencing social stresses such as family conflicts or have in their history childhood trauma or sexual abuse. Many are also dealing with issues related to depression or addiction.

A media culture that bombards us with pictures and videos of ultra-thin women and “ripped” men is another key contributor, Mysko said.

The disorders take a heavy toll. People can lose hair and suffer constipation. Becoming malnourished can affect heart health, weakening the heart muscle and creating electrolyte imbalances, Weigel said. Malnourishment can stunt bone growth and cause osteoporosis and fractures in young patients.

Recovery includes individual and sometimes family therapy, as well as fostering healthy eating habits.

While panelists agreed that recognition of eating disorders is still too low, they also said there has been an international push to address the issue in the modeling industry, by standardizing certain health criteria for models. In the United States, advocates have begun to lobby the Occupational Safety and Health Administration to develop guidelines for the modeling industry. Some retailers, including American Eagle, have lately made an effort to feature models with a more realistic physique.

Panelists offered a suite of recommendations to address the problem, including early screening for eating disorders, encouraging pediatricians to ask patients about binging and purging, restoring monitoring of eating disorders by the Centers for Disease Control and Prevention, getting states to ban the sale of diet pills and muscle-building supplements to minors, and closing loopholes that let insurance companies deny coverage.

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Though scientists have long known that mice can pick out scents — the smell of food, say, or the odor of a predator — they have been at a loss to explain how they are able to perform that seemingly complex task so easily.

But a new study, led by Venkatesh Murthy, professor of molecular and cellular biology, suggests that the means of processing smells may be far simpler than researchers realized.

Using a machine-learning algorithm, Murthy and colleagues were able to “train” a computer to recognize the neural patterns associated with various scents, and to identify whether specific odors were present in a mix of smells. The study is described in a Sept. 1 paper in the journal Neuron.

Along with Murthy, the paper was co-authored by Alexander Mathis, Dan Rokni, and Vikrant Kapoor, postdoctoral fellows working in Murthy’s lab, and Professor Matthias Bethge from the Werner Reichardt Centre for Integrative Neuroscience & Institute of Theoretical Physics in Germany.

“It’s easy to identify the smell of coffee on its own. But if the smell of cinnamon and flowers is mixed in, can I still identify the coffee?” Murthy said. “In an earlier study, we tested that in mice, and found they can do it very well.

“With this study, [we wanted to test] if we could build an algorithm … to do this in a computer, and what surprised us was how easy it is,” he said. “Initially, we thought it would be very complicated, but if you lay it out like a logic problem, it’s basically picking out a specific neural activation pattern that’s buried in a mix of patterns, and from a computer science perspective that’s do-able. The problem could be solved with a very simple linear classifier. It didn’t need the complexity and non-linearity that is built into deep neural networks. It’s no wonder mice were able to learn it so quickly and do it so well.”

Essentially, Murthy said, the algorithm works like any other pattern-recognition system, only the patterns are the neural activation patterns of mice reacting to particular odors.

Sense of scents

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Sense of scents

By Peter Reuell, Harvard Staff Writer | August 15, 2014

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“Essentially, one odor causes a particular neural activation pattern, and another odor causes a different pattern,” he said. “When you start mixing odors, eventually those patterns will overlap. Mice have about 1,000 types of olfactory receptors, but a given odor only activates maybe 10 percent of them. That’s sparse enough that, even if you have many scents mixed, they can still parse them out. What the algorithm does is look at those patterns, and even if they are partly occluded (by another odor), it can recognize that a particular pattern is there.”

To “train” the algorithm to recognize those patterns, Murthy and colleagues gathered data on the neural activation patterns associated with various odors by imaging the brains of mice over thousands of trials. The team then used 80 percent of that data to train the system to recognize patterns of activation for particular odors, even when those patterns were masked by a mixture of other scents.

“The computer looks at the patterns, randomly selects pixels, and adds them up,” Murthy explained. “If they reach a certain level, it says the target is there. Initially, though, it is almost certainly going to make a mistake. There’s then a process of fitting, in which we take the responses the computer gave and the actual responses, and we train it with the correct answers.”

Over thousands of trials, Murthy said, the algorithm eventually became as adept as mice at identifying whether a specific odor was present in a mixture of scents, suggesting that mice may be employing a similar algorithm.

Once they’d shown that the algorithm could identify target odors, Murthy and colleagues set out to trick it, not by making the scent mixtures more complex but by making them less so. Rather than training the computer with mixtures of various scents, researchers trained it exclusively with individual odors, and only exposed it to mixtures later. The result, Murthy said, was disastrous. Though the algorithm could easily identify single odors, it quickly broke down as mixtures became more complex.

When Murthy and colleagues ran the same experiment using mice, they found the same result.

“That was a surprise,” Murthy said. “What we think was happening is if both the algorithm and mouse establish that boundary for how to classify things when the world is simple, as the world gets more and more complex, that’s no longer the proper boundary.”

In addition to shedding light on how mice are able to discern individual scents, the study points toward computer-learning algorithms as potentially powerful tools to examine olfaction, and a way to design and conduct experiments in a virtual space before conducting them in the real world.

“Moving forward, we’re excited about this because we want to design experiments for mice and humans that test new questions, for example, what odor experience will best improve smell detection skills, and is supervised learning necessary for improvement?” Murthy said. “The computer algorithms used in our work can generate strong hypotheses for testing.”

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The steady fade of our analog past continued this month when Apple released its latest smartphone, the iPhone 7, without a headphone jack.

Amid the hue and cry from those who use headphones to listen to music while running, talk on the phone while driving, or block out subway crowds, the Gazette tracked down Woodward Yang, the Gordon McKay Professor of Electrical Engineering and Computer Science, a University Fellow at Harvard Business School, and faculty co-director of the new master’s program in design engineering at the John A. Paulson School of Engineering and Applied Sciences and the Graduate School of Design. Yang has kept an eye on the cellphone industry since he developed the CMOS image sensor that is common in cellphone cameras. He also testified as an expert witness in Apple’s patent infringement lawsuit against Samsung.

Yang, an iPhone user, doesn’t count himself among the outraged — he confessed he barely uses headphones — and said that old technology has to make way for new, especially in a small device such as a smartphone. (He also pointed out that Apple has allowed for headphone connectivity via the phone’s Lightning port.) The key question, Yang said, is what Apple will do with the freed-up space.

GAZETTE: Apple has always been a trendsetter: They got rid of the floppy disk. The latest is the loss of the headphone jack. Is this a big deal, or will we look back at it with a shrug?

YANG: There are a couple of different ways to run your business. One strategy for approaching your business is like what Alfred Sloan of General Motors said: “A car for every purse and purpose.” They tried to design a different automobile that specifically targeted the lifestyle and budget of particular segments of their customers. Then the flip side of doing this was Henry Ford’s approach. Ford was allegedly quoted as saying, “If I asked my customers what they wanted, it would be a faster horse.” So Ford gave them what he knew they wanted, but they didn’t know they wanted yet.

You need to understand the business that you’re in. Do you need to create a phone or a car for every customer that you have and individualize? Or are you in the mode where you’re delivering the best in technology and you’re giving people stuff that they never imagined that they needed yet? That’s where Apple thinks they are. If they [want to be] on the cutting edge, the bleeding edge, then they have to make these tradeoffs. You can’t forever keep compatibility, otherwise you’d still have the VHS tape and a CD-ROM player and a floppy disk in our laptops and the laptop wouldn’t be very small. I think that they’re trying to make the tradeoff so they can deliver the product that you didn’t know you really wanted.

GAZETTE: And what are those products?

YANG: The products are going to do things for you that you never knew that you wanted them to do. What they’re going to do is, hopefully, make your life more enjoyable, more comfortable, more convenient, more productive. If you look at the cell phone, it’s just amazing what it has become. A long time ago, a cellphone was just a phone. The great thing was you could actually have your lists of phone numbers there, your contacts. But now people play music on it, listen to podcasts on it, check your stocks, check your email … you shop, right? You stay in touch with your friends through Facebook or Snapchat. It’s doing all these new things, and who knows what the phone will do for you next year or in five years or in 10 years?

GAZETTE: I think Apple explained it as making room for a faster processor and a battery was the other thing …

YANG: The faster processor is marketing hooey. The space for that doesn’t make for a faster processor. The space for that does make room for more battery. And you need more battery for a faster processor, because the faster processor can use more power. I believe that the new iPhone 7, from what I’ve read — I’m not an Apple expert, and I don’t always believe what I read, but it said the battery life is two hours longer. So you say, “Oh, you got rid of my analog headset but you made my phone battery last two hours longer.” I don’t think you could have both, because the amount of space that the headset connector takes is pretty significant.

GAZETTE: But to look at the flip side of that, it strikes me that the headphone is probably one of the most widely used accessories for a smartphone today …

YANG: Is it?

GAZETTE: I think so, but you tell me …

YANG: The accessory that’s probably used by everybody is the RF [radio frequency] connection for Wi-Fi and the touchscreen. I have a headphone set and I’ve been using an iPhone for quite a while. It’s just something I carry around, but never use. But I know that some people do use it a lot, so the people who are most upset are those whose lives are being disrupted by this lack of a headphone jack. But they’re not getting rid of the headphone per se, you can still have a wired headphone that fits into the Lightning socket. So I don’t think it’s weird or tragic that it’s not there.

GAZETTE: Just to follow up on your comments about the battery. A friend has Bluetooth headphones that have to be plugged in. So now you need headphones with batteries in them and there are more things to charge and more batteries to run down.

YANG: The battery issue is already complex. The first thing to die limits what you can do; I do believe that. But for myself I just don’t use the headphones all that much in my everyday life. My car has hands-free Bluetooth connectivity. In my office and at home, I have Amazon Echo, which plays music. I just don’t find myself needing headphones except on an airplane. For other people, if you listen to music while you exercise, for example, I think that you are probably going to be a little upset about that. But it’s not that the headphone’s gone, you can still get a Lightning headphone. I’m not sure it is as revolutionary or disruptive as people are playing it up to be.

GAZETTE: What do you think is going to be the next big smartphone innovation and who is driving that innovation these days, as Apple has done so regularly?

YANG: Innovation, at least as related to the mobile phone, has been happening for a long time. The things that we see now are actually the result of lots of different things that have happened over the past 30 to 40 years: developments in science, technology, engineering, the ability to make faster and faster chips smaller and smaller, differences and changes in laws and regulations to allow licensing, the massive infrastructure to do this. If you look at this, the nature of the innovation in telephony has been changing over the last 30 years from all the things that led to the mobile phone. Probably up until the late ’90s or early 2000s, it was a technological challenge just to get everything to work. Completing a phone call was almost a miracle back then. It was really a technological issue. You were happy, you didn’t complain. But eventually everybody was actually able to make the phone work. Nokia made a phone work, Motorola made a phone work. Everybody can make a phone work. Gee, even Apple, who had no technical background in mobile telephony technology at the time, can make a phone.

And then it happened, because the tech had been well established, the innovation, the differentiation moved to a different level. It wasn’t who could make the best phone connection, because they’re all really good. It was who could provide it in a format that was easy to use, and fun. And then we start to move into the smartphone. Now, the question becomes who can combine that [smartphone] with interesting services, so you can see information that you want to see? Who could make a phone that works all over the world without you having to have extravagant roaming charges? I think in the ’90s and early 2000s there were massive roaming charges if you just went from Massachusetts to New Hampshire. Now, all over the United States there are no roaming charges. Are we going to a day where there will be no roaming charges for the entire world? That’d be nice, wouldn’t it?

I don’t know where the innovation is going to happen. Apple was positioned nicely when the innovations were occurring in how to configure it to be user-friendly, because that’s what Apple does really well. But now, are we moving to the point where everybody can make a user-friendly phone? … Is innovation going to move to something else where the value for the innovation isn’t in the device? It might be how the devices are connected together. I don’t know if Apple will be able to make that transition. I don’t know where the next innovation is going to happen, in the device or in something on the device. And I don’t know if Apple will be able to continue to make innovations in the device. The iPhone 7 is a little disappointing.

GAZETTE: What would you like to see? What functionality or device if you could wave a magic wand?

YANG: At this point, I’ve seen so many unintended consequences of technology that I think it’s really dangerous to wish for something. Because you might get what you wished for. I’m sure a lot of older people out there wished they could have a phone that could go everywhere with them, so they wouldn’t have to be tied down to the office. Now they have a cellphone and they never sleep. Those same people wished, oh, it would be so great to get my email where I am, so I wouldn’t have to be at the office. Now the office follows them wherever they go. And so I think we have to be careful what we wish for, because we might get what we wish for and it might also change the situation and circumstances that you’re living in in a negative way.

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If you look, you will find … something.

That’s a lesson Hannah Zurier ’17 learned after she approached Asa Gray Professor of Systematic Botany Donald Pfister a couple of years ago about a research project.

Zurier had a passion for science and an interest in cooking. She wondered whether Pfister, an expert in fungal biology who was then serving as interim dean of Harvard College, might help her develop a project that blended the two through exploration of the famed white truffle fungus.

But instead of finding something to eat, Zurier found something nobody had seen before — the truffle of a related but mysterious species. Working under the guidance of postdoctoral fellow Rosanne Healy, Zurier described the fungus fully to science for the first time and helped give it a name, Tuber arnoldianum, after the site of its discovery, Harvard’s Arnold Arboretum.

The new truffle, turns out, is native and relatively common, found on four of the 13 trees the researchers examined. The pair concluded that T. arnoldianum, far from being shy and retiring, is the dominant species among the trees they sampled. The research describing it, which came out in June in the journal Mycorrhiza, called it an “aggressive colonizer.”

“It was really cool to find this species that was everywhere but no one had found it before,” Zurier said. “I started the summer on one truffle and wound up on a completely different project. That’s the way science works.”

Even an aggressive fungus can be hard to notice. Truffles exist symbiotically with tree roots, exchanging nutrients that the truffle fungus pulls in from the soil for carbohydrates provided by the tree.

In addition, as with all soil fungi, the fungus’ main body isn’t the truffle itself. The truffle is what scientists call a “fruiting body” — the equivalent of an apple on an apple tree — that comes and goes while the main fungal body, made up of a network of tiny threads called hyphae, carries on year-round like the apple tree.

Along with making them hard to detect, truffles’ subterranean nature helps create their prized flavor and scent, which are attractive to animals such as the pigs used to hunt culinary truffles in Southern Europe. From the truffle’s standpoint, it’s advantageous to have an animal dig it up and spread the spores.

The Arboretum discovery came after Pfister assigned Zurier to work with Healy, who was searching the Arboretum for white truffles, the most highly prized — and expensive — of the culinary truffles. A 2½-pound white truffle sold in 2010 for more than $400,000.

Healy was following up on white truffle DNA discovered during soil comparisons at the Arboretum and at Harvard Forest. Since the white truffle is native to Europe and hard to cultivate elsewhere, Healy wanted to know more about that DNA, found on a native red oak tree in the Arboretum, and where it might have come from. She focused on a group of Arboretum trees that had been imported from Europe before 1921, when the U.S. government banned importation of trees bundled with soil in an effort to curb imported pests and diseases.

The search turned up eight truffle species, including the new one. Though the researchers were the first to find the new truffle fungus’ fruiting body, there had been an earlier indication that it existed. Its DNA was detected in an environmental soil screen, but with no more evidence it could not be fully described and was dubbed “Tuber species 46.” That left it to Zurier and Healy to do the painstaking work of description.

“We’ll do the phylogeny,” Pfister said of species detected only through DNA found in the environment, but “we won’t have the slightest idea what it looks like.”

The project provides several lessons, Pfister said. One is that research can be a valuable part of the undergraduate experience at Harvard. While Zurier’s chance to describe a new species is unusual, students can have rewarding experiences working on subjects that interest them, and they don’t have to do so solely within the confines of a class or in preparation for a senior honors thesis, he said.

“We want our students to reach out and find a project that catches their eye and their passion,” Pfister said. “It’s much more important to find something you want to work on and investigate. Forget about whether it ends up as a thesis and an honors grade.”

Another lesson is the value of environmental sampling, a practice enabled in recent years by advances in DNA technology. Rather than targeting a single species at a time for sampling, scientists today can sample the environment itself (in this case the soil around a tree), extract all the DNA associated with it, and then determine how many different species are active there.

Zurier, who worked on the project through the summer of 2014 and into that fall, said she particularly enjoyed what she described as the “treasure hunt” portion of the project, searching for truffle fungi on the trees. Still, more time was spent in the laboratory, carefully examining different parts of the new truffle fungus, from the truffle body itself to the hyphae to the tiny spores — dimpled and spiked — that the truffle disperses.

An additional benefit of the project, Zurier said, was exploring the 281-acre Arboretum, in Jamaica Plain.

“I got to see how awesome it is. It’s really beautiful.”

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A new analysis of a key contributor to the marine food web has turned up a surprising twist: more unique species in cooler waters than in the tropics, a reversal of the situation on land.

The findings highlight the need to direct limited conservation dollars according to science, with a focus on places where biodiversity is most at risk, said Barnabas Daru, Harvard Herbaria Postdoctoral Fellow in Organismic and Evolutionary Biology, who performed the analysis on the world’s 70 species of seagrass.

Daru acknowledged that seagrass isn’t as exciting as sharks or tuna, or as marine mammals such as seals, dolphins, and manatees. But for anyone who cares about the health of marine animals, he said, the role of humble seagrass at the beginning of the marine food chain is key.

“The focus is often on animals, but anything that affects plants will have a cascading effect on everything higher up in the food chain,” Daru said.

In other words, the creatures that eat seagrass are eaten by meat eaters, which are in turn eaten by larger meat eaters, such as sharks. In addition, seagrass meadows provide a host of ecosystem services, storing carbon as they grow, minimizing erosion by stabilizing marine sediments, and serving as nurseries where many fish and invertebrate species lay their eggs and where their offspring seek shelter early in their lives.

seagrass
Seagrass beds have been under assault globally. In Boston Harbor, vast seagrass beds have now dwindled to a bare remnant, roughly 750 acres of the 16,000 acres once thought to cover the harbor. Photo courtesy of Wikimedia Commons

Seagrass beds have been under assault globally. The grasses, which includes widespread eelgrass and turtlegrass, live entirely submerged, making them distinct from more familiar beach vegetation that is covered and uncovered by the tides. Like all plants, seagrasses depend on the sun to power photosynthesis, which means they live mainly in shallow coastal waters, leaving them vulnerable to pollution, dredging, habitat change, and rising temperatures.

In Boston Harbor, vast seagrass beds have now dwindled to a bare remnant, roughly 750 acres of the 16,000 acres once thought to cover the harbor. Statewide, 90 percent of the remaining beds are in decline, according to the Massachusetts Bays Program.

Daru’s research, published last month in the journal Biological Conservation, combined DNA analysis with existing data on seagrass distribution worldwide to draw what scientists call a “phylogenetic tree” showing relationships among different grasses. Researchers linked that tree to known patterns of global distribution.

What emerged was a picture that surprised Daru. Unlike patterns of biological diversity on land — where the tropics have more vertebrate species that are evolutionarily distinct and without close relatives — seagrasses show the opposite distribution, with cooler, temperate regions home to more distinct species.

The finding illustrates the importance of science in clarifying species distribution, he said, because that clarity is crucial to proper distribution of conservation funds.

Similarly, Daru said, if efforts aiming to establish protected marine reserves are designed only with fish and mammal diversity in mind, conservationists are missing an opportunity to conserve meadows that the same fish and mammals depend on.

Another discovery in the analysis was that species in the temperate regions approaching the northern and southern poles are more closely related to each other than they are to tropical species, even though they are geographically distant. Ocean currents, particularly those that flow along the sea floor, may have spread the grasses between the two regions, Daru said.

“There is high evolutionary distinctiveness in temperate waters,” Daru said. “It shows there are more evolutionarily old species in temperate environments rather than in tropical warm waters.”

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