120 DAYS OF SODOM

Research reveals why redheads may have different pain thresholds

Study in red-haired mice uncovers mechanisms involved and suggests new treatment strategies for pain

MASSACHUSETTS GENERAL HOSPITAL

Research News

 

BOSTON - New research led by investigators at Massachusetts General Hospital (MGH) provides insights on why people with red hair exhibit altered sensitivity to certain kinds of pain. The findings are published in Science Advances.

In people with red hair (as in numerous other species of animals with red fur), the pigment-producing cells of the skin--called melanocytes--contain a variant form of the melanocortin 1 receptor. This receptor sits on the cell surface, and if it becomes activated by circulating hormones called melanocortins, it causes the melanocyte to switch from generating yellow/red melanin pigment to producing brown/black melanin pigment. Earlier work by David E. Fisher, MD, PhD, director of the Mass General Cancer Center's Melanoma Program and director of MGH's Cutaneous Biology Research Center, demonstrated that the inability of red-haired individuals to tan or darken their skin pigment is traced to inactive variants of this receptor.

To investigate the mechanisms behind different pain thresholds in red-haired individuals, Fisher and his colleagues studied a strain of red-haired mice that (as in humans) contains a variant that lacks melanocortin 1 receptor function and also exhibits higher pain thresholds.

The team found that loss of melanocortin 1 receptor function in the red-haired mice caused the animals' melanocytes to secrete lower levels of a molecule called POMC (proopiomelanocortin) that is subsequently cut into different hormones including one that sensitizes to pain and one that blocks pain. The presence of these hormones maintains a balance between opioid receptors that inhibit pain and melanocortin 4 receptors that enhance perception of pain.

In red-haired mice (and therefore, possibly humans), having both hormones at low levels would seemingly cancel each other out. However, the body also produces additional, non-melanocyte-related factors that activate opioid receptors involved in blocking pain. Therefore, the net effect of lower levels of the melanocyte-related hormones is more opioid signals, which elevates the threshold for pain.

"These findings describe the mechanistic basis behind earlier evidence suggesting varied pain thresholds in different pigmentation backgrounds," says Fisher. "Understanding this mechanism provides validation of this earlier evidence and a valuable recognition for medical personnel when caring for patients whose pain sensitivities may vary."

Fisher adds that the results suggest new ways to manipulate the body's natural processes that control pain perception--for example, by designing new medications that inhibit melanocortin 4 receptors involved in sensing pain.

"Our ongoing work is focused on elucidating how additional skin-derived signals regulate pain and opioid signaling," adds co-lead author Lajos V. Kemény, MD, PhD, a research fellow in Dermatology at MGH. "Understanding these pathways in depth may lead to the identification of novel pain-modulating strategies."

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This work was supported by the National Institutes of Health, the Melanoma Research Alliance, the U.S.-Israel Binational Science Foundation, and the Dr. Miriam and Sheldon G. Adelson Medical Research Foundation.

About the Massachusetts General Hospital

Massachusetts General Hospital, founded in 1811, is the original and largest teaching hospital of Harvard Medical School. The Mass General Research Institute conducts the largest hospital-based research program in the nation, with annual research operations of more than $1 billion and comprises more than 9,500 researchers working across more than 30 institutes, centers and departments. In August 2020, Mass General was named #6 in the U.S. News & World Report list of "America's Best Hospitals."

UConn researcher develops successful Zika vaccine in preclinical studies

The vaccine is generated from a novel platform technology

UNIVERSITY OF CONNECTICUT

Research News

 

IMAGE: PAULO VERARDI, ASSOCIATE PROFESSOR OF PATHOBIOLOGY AND VETERINARY SCIENCE IN UCONN'S COLLEGE OF AGRICULTURE, HEALTH AND NATURAL RESOURCES view more 

CREDIT: UCONN PHOTO

UConn researcher Paulo Verardi, associate professor of pathobiology and veterinary science in the College of Agriculture, Health and Natural Resources, has demonstrated the success of a vaccine against Zika virus and recently published his findings in Scientific Reports, a Nature Research publication. He has also filed provisional patent for the novel vaccine platform technology used to generate the vaccine, as well as genetic modifications made to the vaccine that significantly enhance expression of the vaccine antigen.

Verardi, a Brazilian native, was in Brazil visiting family in the summer of 2015 when the Zika outbreak first began to make waves and soon reached epidemic status.

Back in the United States, Verardi kept tabs on the Zika epidemic and its emerging connection to microcephaly, a serious birth defect that causes babies to be born with small heads and underdeveloped brains.

In October of that year, Verardi called then-Ph.D.-student Brittany Jasperse (CAHNR '19) into his office and told her he wanted to apply their newly developed vaccine platform and start developing a vaccine for Zika virus.

Verardi and Jasperse were among the first researchers in the US to receive NIH funding to generate a vaccine against Zika virus, thanks to Verardi recognizing the significance of Zika virus early.

Modern advancements in genomic technology have expediated the vaccine development process. In the past, researchers needed to have access to the actual virus. Now just obtaining the genetic sequence of the virus can be sufficient to develop a vaccine, as was the case for the Zika vaccine Verardi and Jasperse developed, and the COVID-19 vaccines currently approved for emergency use in the United States and abroad.

Using the genetic sequence of Zika virus, Verardi and Jasperse developed and tested multiple vaccine candidates that would create virus-like particles (VLPs). VLPs are an appealing vaccine approach because they resemble native virus particles to the immune system and therefore trigger the immune system to mount a defense comparable to a natural infection. Critically, VLPs lack genetic material and are unable to replicate.

The vaccine Verardi and Jasperse developed is based on a viral vector, vaccinia virus, which they modified to express a portion of Zika virus' genetic sequence to produce Zika VLPs. Their vaccine has an added safety feature that it is replication-defective when given as a vaccine but replicates normally in cell culture in the lab.

"Essentially, we have included an on/off switch," Jasperse says. "We can turn the viral vector on in the lab when we're producing it by simply adding a chemical inducer, and we can turn it off when it's being delivered as a vaccine to enhance safety."

The team developed five vaccine candidates in the lab with different mutations in a genetic sequence that acts as a signal to secrete proteins. They evaluated how these mutations affected the expression and formation of Zika VLPs and then selected the vaccine candidate that had the highest expression of VLPs to test in a mouse model of Zika virus pathogenesis. This model was developed by Helen Lazear of University of North Carolina at Chapel Hill, whose lab Jasperse now works in as a postdoctoral research associate.

Verardi and Jasperse found that mice who received just a single dose of the vaccine mounted a strong immune response and were completely protected from Zika virus infection. They did not find any evidence of Zika virus in the blood of challenged mice who were exposed to the virus after vaccination.

Zika virus is part of a group of viruses known as flaviviruses which include dengue virus, yellow fever virus, and West Nile virus. Verardi and Jasperse's findings, particularly the mutations they identified that enhanced expression of Zika VLPs, could be useful for improving production of vaccines against diseases caused by other related flaviviruses.

Ongoing work in the Verardi lab incorporates these novel mutations into vaccine candidates against other viruses, including Powassan virus, a tick-borne flavivirus that can cause fatal encephalitis.

Verardi emphasizes that developing vaccines for viruses, in this case Zika, help the world be better prepared for outbreaks of novel and emerging viruses by having vaccine development frameworks in place.

"Emerging viruses are not going to stop popping up any time soon, so we need to be prepared," Verardi says. "Part of being prepared is to continue the development of these platforms."

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Time to shift from 'food security' to 'nutrition security' to increase health and well-being

Tufts and Georgetown scientists, and humanitarian José Andrés, call for a new approach to address food and nutrition inequities

TUFTS UNIVERSITY, HEALTH SCIENCES CAMPUS

Research News

 

IMAGE: CHEF JOSÉ ANDRÉS SPEAKING TO A GROUP OF PEOPLE IN CALIFORNIA (PRE-COVID IMAGE). view more 

CREDIT: SAMANTHA HIGGINS FOR WORLD CENTRAL KITCHEN.

In the 1960s, a national focus on hunger was essential to address major problems of undernutrition after World War II. In the 1990s, the nation shifted away from hunger toward "food insecurity" to better capture and address the challenges of food access and affordability.

Now, a new Viewpoint article argues that today's health and equity challenges call for the U.S. to shift from "food insecurity" to "nutrition insecurity" in order to catalyze appropriate focus and policies on access not just to food but to healthy, nourishing food.

The Viewpoint, by Dariush Mozaffarian of the Friedman School of Nutrition Science & Policy at Tufts University, Sheila Fleischhacker of Georgetown Law School, and José Andrés of World Central Kitchen, was published online in JAMA this week.

The concept of food security focuses on access to and affordability of food that is safe, nutritious, and consistent with personal preferences. In reality, however, the "nutritious" part often has been overlooked or lost in national policies and solutions, with resulting emphasis on quantity, rather than quality, of food, say the authors.

"Food is essential both for life and human dignity. Every day, I see hunger, but the hunger I see is not only for calories but for nourishing meals. With a new focus on nutrition security, we embrace a solution that nourishes people, instead of filling them with food but leaving them hungry," said Chef José Andrés, founder of World Central Kitchen.

The authors define nutrition security as having consistent access to and availability and affordability of foods and beverages that promote well-being, while preventing -- and, if needed, treating -- disease. Nutrition security provides a more inclusive view that recognizes that foods must nourish all people.

"'Nutrition security' incorporates all the aims of food security but with additional emphasis on the need for wholesome, healthful foods and drinks for all. COVID-19 has made clear that Americans who are most likely to be hungry are also at highest risk of diet-related diseases including obesity, diabetes, heart disease, and many cancers - a harsh legacy of inequities and structural racism in our nation. A new focus on nutrition security for all Americans will help crystallize and catalyze real solutions that provide not only food but also well-being for everyone," said first author Dariush Mozaffarian, dean of the Friedman School of Nutrition Science & Policy at Tufts University.

"It's the right time for this evolution," said Sheila Fleischhacker, adjunct professor at Georgetown Law School, who has drafted food, nutrition and health legislation and campaign positions at the local, state, tribal and federal levels. "By prioritizing nutrition security, we bring together historically siloed areas - hunger and nutrition - which must be tackled together to effectively address our modern challenges of diet-related diseases and disparities in clinical care, government food and food assistance policies, public health investments, and national research."

"The current approach is not sufficient," the authors write, and "traditionally marginalized minority groups as well as people living in rural and lower-income counties are most likely to experience disparities in nutrition quality, food insecurity, and corresponding diet-related diseases."

New research on Alzheimer's Disease shows 'lifestyle origin at least in some degree'

AD-stricken brains show a genetic deficit in ability to use glucose

BRIGHAM YOUNG UNIVERSITY

Research News

 

For years, research to pin down the underlying cause of Alzheimer's Disease has been focused on plaque found to be building up in the brain in AD patients. But treatments targeted at breaking down that buildup have been ineffective in restoring cognitive function, suggesting that the buildup may be a side effect of AD and not the cause itself.

A new study led by a team of Brigham Young University researchers finds novel cellular-level support for an alternate theory that is growing in strength: Alzheimer's could actually be a result of metabolic dysfunction in the brain. In other words, there is growing evidence that diet and lifestyle are at the heart of Alzheimer's Disease.

"Alzheimer's Disease is increasingly being referred to as insulin resistance of the brain or Type 3 Diabetes," said senior study author Benjamin Bikman, a professor of physiology and developmental biology at BYU. "Our research shows there is likely a lifestyle origin to the disease, at least to some degree."

For the new study, published in academic journal Alzheimer's & Dementia, the BYU research team examined RNA sequences in 240 post-mortem Alzheimer's Disease-impacted brains. They were looking specifically at the gene expression of nervous system support cells during two types of metabolism: glucose metabolism, where carbohydrates are broken down to provide energy, and something called ketolytic metabolism.

Ketolytic metabolism involves the brain creating energy from ketones, molecules made in our body when the hormone insulin is low and we are burning relatively higher amounts of fat. The popular "Keto Diet" is named after the process since that low-carb, high-protein diet lowers insulin levels and causes the body to burn fat instead of carbs and produce ketones.

The researchers found widespread glucose metabolism impairment in those nervous system support cells of the brains of former Alzheimer's Disease patients, but limited ketolytic metabolism impairment. The finding is significant because the brain is like a hybrid engine, with the ability to get its fuel from glucose or ketones, but in the Alzheimer's brains studied, there appears to be a fundamental genetic deficit in the brain's ability to use glucose.

"We've turned the hybrid engine of our brains into a mono-fuel system that just fails to thrive," Bikman said. "And so, the brain, which is progressively becoming deficient in its ability to use glucose, is now crying out for help; it's starving in the midst of plenty. The body is swimming in a sea of glucose, but the brain just can't use it.

"The inability to use glucose increases the value of ketones. However, because the average person is eating insulin-spiking foods so frequently, there's never any ketones available to the brain," Bikman added. "I look at these findings as a problem we've created and that we're making worse."

Previous research has observed that the brains of people with AD have a quantifiable reduction in the ability to take in and use glucose, but this paper is the first to show it actually happens at the cellular level. It's a significant contribution to the growing paradigm shift in regards to the scientific view of the causes of Alzheimer's.

And since ketolytic metabolism seems to keep working fine in people with AD, even when glucose metabolism gives out, the paper concludes that treatments involving ketones may be able to support brain metabolism and slow the cognitive decline associated with the disease.

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Study authors, which include BYU professor Justin Miller and former BYU professor John Kauwe (now president of BYU-Hawaii), suggest future research investigate metabolic dysfunction in Alzheimer's Disease brains should target oligodendrocytes because genes involved in ketolysis and glycolysis are both differentially expressed in that cell type in AD brains.

Study co-authors also included Oscar Harari, Carlos Cruchaga and Kathie Mihindukulasuriya from the Washington University School of Medicine.

 THE FUTURE AMAZON WORKER

A robot that senses hidden objects

System uses penetrative radio frequency to pinpoint items, even when they're hidden from view

 The technology could aid fulfilment in e-commerce warehouses.

MASSACHUSETTS INSTITUTE OF TECHNOLOGY

Research News

 

IMAGE: MIT RESEARCHERS DEVELOPED A PICKING ROBOT THAT COMBINES VISION WITH RADIO FREQUENCY (RF) SENSING TO FIND AND GRASPS OBJECTS, EVEN IF THEY'RE HIDDEN FROM VIEW. THE TECHNOLOGY COULD AID FULFILMENT... view more 

CREDIT: IMAGE COURTESY OF FADEL ADIB, TARA BOROUSHAKI, ALBERTO RODRIGUEZ

In recent years, robots have gained artificial vision, touch, and even smell. "Researchers have been giving robots human-like perception," says MIT Associate Professor Fadel Adib. In a new paper, Adib's team is pushing the technology a step further. "We're trying to give robots superhuman perception," he says.

The researchers have developed a robot that uses radio waves, which can pass through walls, to sense occluded objects. The robot, called RF-Grasp, combines this powerful sensing with more traditional computer vision to locate and grasp items that might otherwise be blocked from view. The advance could one day streamline e-commerce fulfillment in warehouses or help a machine pluck a screwdriver from a jumbled toolkit.

The research will be presented in May at the IEEE International Conference on Robotics and Automation. The paper's lead author is Tara Boroushaki, a research assistant in the Signal Kinetics Group at the MIT Media Lab. Her MIT co-authors include Adib, who is the director of the Signal Kinetics Group; and Alberto Rodriguez, the Class of 1957 Associate Professor in the Department of Mechanical Engineering. Other co-authors include Junshan Leng, a research engineer at Harvard University, and Ian Clester, a PhD student at Georgia Tech.

As e-commerce continues to grow, warehouse work is still usually the domain of humans, not robots, despite sometimes-dangerous working conditions. That's in part because robots struggle to locate and grasp objects in such a crowded environment. "Perception and picking are two roadblocks in the industry today," says Rodriguez. Using optical vision alone, robots can't perceive the presence of an item packed away in a box or hidden behind another object on the shelf -- visible light waves, of course, don't pass through walls.

But radio waves can.

For decades, radio frequency (RF) identification has been used to track everything from library books to pets. RF identification systems have two main components: a reader and a tag. The tag is a tiny computer chip that gets attached to -- or, in the case of pets, implanted in -- the item to be tracked. The reader then emits an RF signal, which gets modulated by the tag and reflected back to the reader.

The reflected signal provides information about the location and identity of the tagged item. The technology has gained popularity in retail supply chains -- Japan aims to use RF tracking for nearly all retail purchases in a matter of years. The researchers realized this profusion of RF could be a boon for robots, giving them another mode of perception.

"RF is such a different sensing modality than vision," says Rodriguez. "It would be a mistake not to explore what RF can do."

RF Grasp uses both a camera and an RF reader to find and grab tagged objects, even when they're fully blocked from the camera's view. It consists of a robotic arm attached to a grasping hand. The camera sits on the robot's wrist. The RF reader stands independent of the robot and relays tracking information to the robot's control algorithm. So, the robot is constantly collecting both RF tracking data and a visual picture of its surroundings. Integrating these two data streams into the robot's decision making was one of the biggest challenges the researchers faced.

"The robot has to decide, at each point in time, which of these streams is more important to think about," says Boroushaki. "It's not just eye-hand coordination, it's RF-eye-hand coordination. So, the problem gets very complicated."

The robot initiates the seek-and-pluck process by pinging the target object's RF tag for a sense of its whereabouts. "It starts by using RF to focus the attention of vision," says Adib. "Then you use vision to navigate fine maneuvers." The sequence is akin to hearing a siren from behind, then turning to look and get a clearer picture of the siren's source.

With its two complementary senses, RF Grasp zeroes in on the target object. As it gets closer and even starts manipulating the item, vision, which provides much finer detail than RF, dominates the robot's decision making.

RF Grasp proved its efficiency in a battery of tests. Compared to a similar robot equipped with only a camera, RF Grasp was able to pinpoint and grab its target object with about half as much total movement. Plus, RF Grasp displayed the unique ability to "declutter" its environment -- removing packing materials and other obstacles in its way in order to access the target. Rodriguez says this demonstrates RF Grasp's "unfair advantage" over robots without penetrative RF sensing. "It has this guidance that other systems simply don't have."

RF Grasp could one day perform fulfillment in packed e-commerce warehouses. Its RF sensing could even instantly verify an item's identity without the need to manipulate the item, expose its barcode, then scan it. "RF has the potential to improve some of those limitations in industry, especially in perception and localization," says Rodriguez.

Adib also envisions potential home applications for the robot, like locating the right Allen wrench to assemble your Ikea chair. "Or you could imagine the robot finding lost items. It's like a super-Roomba that goes and retrieves my keys, wherever the heck I put them."

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The research is sponsored by the National Science Foundation, NTT DATA, Toppan, Toppan Forms, and the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS).

How Fortnite and Zelda can up your surgical game (no joke!)

Scalpel? Check. Gaming console? Check. Study finds video games can be a new tool on surgical tray for medical students

UNIVERSITY OF OTTAWA

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IMAGE: STUDY LED BY UNIVERSITY OF OTTAWA STUDENT FINDS VIDEO GAMES CAN BE A NEW TOOL ON SURGICAL TRAY FOR MEDICAL STUDENTS view more 

CREDIT: UNIVERSITY OF OTTAWA

Video games offer students obvious respite from the stresses of studies and, now, a study from a University of Ottawa medical student has found they could benefit surgical skills training.

Arnav Gupta carries a heavy course load as a third-year student in the Faculty of Medicine, so winding down with a game of Legend of Zelda always provides relief from the rigorous of study. But Zelda may be helping improve his surgical education, too, as Gupta and a team of researchers from the University of Toronto found in a paper they recently published in the medical journal Surgery.

"Given the limited availability of simulators and the high accessibility of video games, medical students interested in surgical specialties should know that video games may be a valuable adjunct training for enhancing their medical education, especially in surgical specialties where it can be critical," says Gupta, whose findings were deciphered from a systematic review of 16 studies involving 575 participants.

"Particularly, in robotic surgery, being a video gamer was associated with improvements in time to completion, economy of motion, and overall performance. In laparoscopic surgery, video games-based training was associated with improvement in duration on certain tasks, economy of motion, accuracy, and overall performance," explains Gupta, who has been a gamer since age 8.

This study builds on past reviews and is the first to focus on a specific medical student population where this style of training could be feasibly implemented. Their timely study found some of the most beneficial games for students of robotic surgery and laparoscopy were: Super Monkey Ball, Half Life, Rocket League and Underground. Underground is purposely designed to assist medical students with their robotic surgery training via a video game console.

"While video games can never replace the value of first-hand experience, they do have merit as an adjunctive tool, especially when attempting to replicate important movements to surgery. For example, first-person shooting games require you to translate three dimensional motions onto a two-dimensional screen, which is like the concept of laparoscopic surgery," says Gupta, whose studies are focused on surgery in ophthalmology, which makes games like Resident Evil 4 or Trauma Center: New Blood fitted for his own ambitions.

"I'm not joking when I say that games such as Fortnite have the potential to enhance those necessary movements, providing stronger motivational components and in a low stakes environment."

Reports suggest 55 percent of university students are gamers and enjoy proficiency with video consoles. Yet, many medical students don't admit to owning and using a gaming console.

"I think there definitely is some ambivalence towards video games in medicine," says Gupta, who is also a fan of Witcher 3. "Given how accessible games have become and how video game technology is advancing, video games definitely are an easy go-to for the students who do love them in some capacity. The hope is that maybe this study can inspire someone to take advantage of video games' unique capabilities, reduce the general ambivalence towards it, and develop some fun ways to let students engage with surgical education."

CAPTION

"While video games can never replace the value of first-hand experience, they do have merit as an adjunctive tool, especially when attempting to replicate important movements to surgery," says University of Ottawa medical student Arnav Gupta, who led the study with colleagues from the University of Toronto.

 

Consumers are searching online but not buying. Why?

Study reveals the keys to more efficient and profitable retargeting campaigns for online marketers

INSTITUTE FOR OPERATIONS RESEARCH AND THE MANAGEMENT SCIENCES

Research News

 

Key Takeaways:

• Discounting or couponing is not the most effective way to tap the power of retargeting in online marketing.
• Customized seller recommendations may be more powerful than discounting.
• Seller auctions that allow marketers to self-select in the retargeting process improve cost efficiency.

CATONSVILLE, MD, April 1, 2021 - Online marketers have seen the pattern: 95%-98% of online visitors search for something, but the search never converts into a purchase and they leave the site without buying. For marketers, this results in speculation and assumptions that can lead to wasted time and investments in ineffective marketing programs.

One of the more common ways online marketers attempt to solve this problem is to "retarget," which tracks those consumers and reconnects with them at a later point by showing display ads when they browse other websites. You've probably noticed this when using Google Search to find something, such as a pair of shoes, and then later when you're reading a separate news site, you're exposed to a number of display ads centered on that very thing you were searching for earlier.

Once that marketer gets your attention, what can they do to increase the likelihood that you will make a purchase? That question is at the center of a new study that reveals what the best approach to increase conversion rates may be.

The research study to be published in the April issue of the INFORMS journal Marketing Science, "Consumer Search and Purchase: An Empirical Investigation of Retargeting Based on Consumer Online Behaviors," is authored by Zhenling Jiang of The Wharton School at the University of Pennsylvania; Tat Chan of Washington University in St. Louis; Hai Che of the University of California; and Youwei Wang of Fudan University in Shanghai.

To conduct their research, the authors analyzed consumer behaviors in response to two distinct marketing strategies. In one approach, they sent out coupons via those retargeted display ads to be redeemed upon purchasing. In the other approach, the authors used the same display ads to provide seller recommendations that centered on a specific product offering customized to the user, but with no coupon or discount.

"We found that while both strategies help increase the conversion rate, the seller recommendations were more effective than coupons," said Jiang. "This told us that providing consumers with the sellers' information that is most relevant to them may be a more effective way to tap the power of retargeting."

To conduct their research, the authors tapped empirical data from Taobao.com, which is owned by Alibaba, and is the largest online retail platform in China. Like other major e-commerce platforms, it collects consumer browsing history and can reach consumers through direct messaging on the platform, either through the website or its mobile app. The researchers built a consumer search model to establish the relationship between consumer preference and search behaviors. They studied the behavior of 104,189 consumers who searched for a specific product among 20 sellers.

"We noticed some predictable patterns," said Jiang. "Consumers who had a higher search intensity for a specific product were more likely to actually make a purchase. Search intensity was measured in the volume of clicks tied to the same search or search term. What we found was that even where the consumer clicked on multiple possible products, it was the first link they clicked on that had the highest potential of generating a sale. In other words, after a more intense search, the consumer is more likely to go back to that initial seller once a decision to make a purchase is made."

In addition to the two basic retargeting strategies - discounting or customization - the authors proposed to use auction as a pricing mechanism to implement the policies. The auction pricing mechanism requires the seller to self-select. This means the seller selects certain criteria for its ideal customer for a specific product at a specific price point, and then bids on how much it will pay to reach that consumer.

"Through our research, we were also able to show that a pricing mechanism, such as an auction, also tends to improve the effectiveness of a retargeting program," said Jiang. "When Taobao used a pricing mechanism such as an auction, the company was able to improve the efficiency of its retargeting campaigns."

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About INFORMS and Marketing Science

Marketing Science is a premier peer-reviewed scholarly marketing journal focused on research using quantitative approaches to study all aspects of the interface between consumers and firms. It is published by INFORMS, the leading international association for operations research and analytics professionals. More information is available at http://www.informs.org or @informs.

Exploring the evolution of Earth's habitability regulated by oxygen cycle

SCIENCE CHINA PRESS

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IMAGE: THE STATUS OF THE OXYGEN CYCLE IN EARTH SYSTEM SCIENCE (A) AND ITS RELATIONSHIP WITH OTHER BIOGEOCHEMICAL CYCLES (B). view more 

CREDIT: @SCIENCE CHINA PRESS

As an essential material for the survival and reproduction of almost all aerobic organisms, oxygen is closely related to the formation and development of complex organisms. A recent review provides a systematic overview of the latest advances in the oxygen cycle at different spatial and temporal scales and the important role that oxygen plays in shaping our current habitable Earth.

Professor Jianping Huang from Lanzhou University is the corresponding author of the review entitled "The oxygen cycle and a habitable Earth", which is the cover article of the 64(4) of SCIENCE CHINA Earth Sciences in 2021.

Based on summarizing the latest research results of predecessors, the authors of this paper propose a coupling model of the five spheres of the earth system with the oxygen cycle as the core, and clarify the link role of the oxygen cycle in it. In this paper, the authors comprehensively summarized the changes of oxygen cycle and its effect on the habitability of the earth on multiple time scales including modern and geological time, and prospected the future development trend of oxygen cycle research.

"We take O2 for granted because it is just there and we breathe it all the time, yet it took billions of years before there was enough of it to keep animals like us alive." Professor Jianping Huang of Lanzhou University, the corresponding author of the paper, points out, "These processes involve the interaction of various spheres of the Earth system, which are complex interdisciplinary issues with multiple temporal and spatial scales." In this paper, the authors illustrate how the key biochemical processes in the oxygen cycle tie together the various spheres of the Earth system through feedback and interaction. "A habitable Earth gradually formed during the long evolution of the oxygen cycle."

The effects of current human activities on the oxygen cycle and biodiversity are also discussed. "Four of the five large-scale species extinctions that have occurred in the history of the earth are related to the lack of oxygen," Professor Huang concluded, "At present, under the compulsion of human activities, our planet is experiencing a large-scale oxygen reduction, with the ocean deoxygenation as a representative. The oxygen cycle of the Earth system is gradually out of balance, which is very worrying."

Studies of the oxygen cycle cover a wide span of timescales from daily to geologic scales. The oxygen cycles of different timescales dominate the control of atmospheric O2 over the corresponding timescales. However, a distinct boundary that divides the long-term and short-term oxygen cycles has yet to be established, and the complex interactions between the short-term and long-term processes remain unclear. Since the earth system is a highly non-linear and strongly coupled system, a minor perturbation can have the potential to cause a series of dramatic changes. "It is a top priority to connect the short-term and long-term oxygen cycles under a comparable timescale rather than separating them. Effective multidisciplinary cooperation among the subdisciplines of Earth sciences (geology, oceanography, atmospheric sciences, paleobiology, etc.), and social sciences should be promoted to reveal the hidden mechanisms that control the trajectory of the Earth system and how the trajectory may influence the future of human beings." said Prof. Huang. Fortunately, efforts have been made to reverse the decline of atmospheric O2. In China, the Green Great Wall, which was designed to mitigate desertification and expand forests has achieved overall success in past decades. Reductions in carbon emission and its related O2 consumption have been achieved in some major cities around the world.

This study has far-reaching scientific significance and important reference value for understanding the potential link between the oxygen cycle and the biodiversity in geological history and exploring the historical evolution and future of the Earth's habitability.

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This work was supported by the National Natural Science Foundation of China (Grant No. 41888101, 41521004 & 41991231), and the China University Research Talents Recruitment Program (111 Projects, Grant No. B13045).

See the article: Huang J, Liu X, He Y, Shen S, Hou Z, Li S, Li C, Yao L, Huang J. 2021. The oxygen cycle and a habitable Earth. Science China Earth Sciences, 64(4): 511-529,
http://doi.org/10.1007/s11430-020-9747-1

 

Study finds airborne release of toxin from algal scum

Study finds a new type of toxin seen to release from scum, which sits on ponds and lakes across the world

TAYLOR & FRANCIS GROUP

Research News

 

A dangerous toxin has been witnessed - for the first time - releasing into the air from pond scum, research published in the peer-reviewed journal Lake and Reservoir Management today shows.

Not only is pond scum - otherwise known as algal bloom - an unsightly formation which can occur on still water across the world, it can also prove dangerous to wildlife and humans.

For the first time, scientists have now detected the presence of the algal toxin anatoxin-a (ATX)which is also known as 'Very Fast Death Factor', in the air near a Massachusetts pond with large algal blooms.

ATX can cause a range of symptoms at acute doses, including loss of coordination, muscular twitching and respiratory paralysis, and has been linked to the deaths of livestock, waterfowl and dogs from drinking contaminated water.

ATX is produced by single celled organisms known as cyanobacteria, which can form harmful algal blooms - when huge amounts of cyanobacteria grow in lake surface waters. Blooms are exacerbated by fertilizer run-off entering lakes or ponds from nearby fields or improperly treated wastewater, and can stimulate growth and high water temperatures. Cyanobacteria, which also are known as blue-green algae, are actually a type of bacteria that can photosynthesize.

Cyanobacterial blooms can also lead to low oxygen conditions, further degrading water quality. This is because when the algae in these large blooms die, they sink to the lake bottom and decompose, which can use up all the oxygen in the water, killing fish and other animals. The blooms also can release toxins into the water that can prove fatal for these animals.

"ATX is one of the more dangerous cyanotoxins produced by harmful algal blooms, which are becoming more predominant in lakes and ponds worldwide due to global warming and climate change," says lead author Dr James Sutherland, at the Nantucket Land Council.

ATX had never been detected in the atmosphere before, but Sutherland and his colleagues suspected that it might become airborne under certain environmental conditions.

To test this possibility, they collected samples of airborne particles from around the edge of Capaum Pond on Nantucket Island in Massachusetts, US, from July to October 2019, when it was regularly covered with algal blooms, by sucking air through a glass fiber filter. They then used an analytical technique called liquid chromatography-tandem mass spectrometry to search for ATX in these samples, as well as in samples of water from the pond.

Not only were they able to detect ATX in the pond water, at concentrations of up to 21ng/mg, but on one occasion they also detected it in the air around the pond, at an average concentration of 0.87ng/filter, which corresponds to a potential airborne exposure of 0.16ng/m3. This detection occurred on a foggy day in September, after a windy night, when the ATX was likely blown from the surface of the water by the strong wind and then protected by the fog, allowing it to be detected.

The researchers are unsure exactly how ATX is released into the air from the pond, whether within small water droplets, attached to aerosol particles or even inside cyanobacteria blown into the air. It is also unclear what effects exposure to these trace concentrations of ATX might have on humans and wildlife, but the fact that there is exposure is clearly a cause for concern and requires further research.

Whilst this new toxin was witnessed in one specific pond, researchers warn caution for people across the world to approach still water with algal blooms. Therefore, further research is needed to test algal blooms in ponds internationally.

"People often recreate around these lakes and ponds with algal blooms without any awareness of the potential problems," said Sutherland. " Direct contact or inhalation of these cyanotoxins can present health risks for individuals, and we have reported a potential human health exposure not previously examined."

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Scientists turn to deep learning to improve air quality forecasts

PENN STATE

Research News

 

Air pollution from the burning of fossil fuels impacts human health but predicting pollution levels at a given time and place remains challenging, according to a team of scientists who are turning to deep learning to improve air quality estimates. Results of the team's study could be helpful for modelers examining how economic factors like industrial productivity and health factors like hospitalizations change with pollution levels.

"Air quality is one of the major issues within an urban area that affects people's lives," said Manzhu Yu, assistant professor of geography at Penn State. "Yet existing observations are not adequate to provide comprehensive information that may help vulnerable populations to plan ahead."

Satellite and ground-based observations each measure air pollution, but they are limited, the scientists said. Satellites, for instance, may pass a given location at the same time each day and miss how emissions vary at different hours. Ground-based weather stations continuously collect data but only in a limited number of locations.

To address this, the scientists used deep learning, a type of machine learning, to analyze the relationship between satellite and ground-based observations of nitrogen dioxide in the greater Los Angeles area. Nitrogen dioxide is largely associated with emissions from traffic and power plants, the scientists said.

"The problem right now is nitrogen dioxide varies a lot during the day," Yu said. "But we haven't had an hourly, sub-urban scale product available to track air pollution. By comparing surface level and satellite observations, we can actually produce estimates with higher spatial and temporal resolution."

The learned relationship allowed the researchers to take daily satellite observations and create hourly estimates of atmospheric nitrogen dioxide in roughly 3-mile grids, the scientists said. They recently reported their findings in the journal Science of the Total Environment.

"The challenge here is whether we can find a linkage between measurements from earth's surface and satellite observations of the troposphere, which are actually far away from each other. That's where deep learning comes in."

Deep learning algorithms operate much like the human brain and feature multiple layers of artificial neurons for processing data and creating patterns. The system learns and trains itself based on connections it finds within large amounts of data, the scientists said.

The scientists tested two deep-learning algorithms and found the one that compared the ground-based observations directly to the satellite observations more accurately predicted nitrogen dioxide levels. Adding information like meteorological data, elevation and the locations of the ground-based stations and major roads and power plants improved the prediction accuracy further.

Yu said the study could be repeated for other greenhouse gases and applied to different cities or on regional and continental scales, the scientists said. In addition, the model could be updated when new, higher-resolution satellites are launched.

"With a high spatiotemporal resolution, our results will facilitate the study between air quality and health issues and improve the understanding of the dynamic evolution of airborne pollutants," Yu said.

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Also contributing to this study was Qian Liu, a doctoral student at the National Science Foundation Spatiotemporal Innovation Center at George Mason University.