Following the wind

Peer-Reviewed Publication

KING ABDULLAH UNIVERSITY OF SCIENCE & TECHNOLOGY (KAUST)

 

IMAGE: KAUST RESEARCHERS HAVE DEVELOPED A MORE ACCURATE METHOD FOR MODELING WIND-DRIVEN PHENOMENA. THEY DEMONSTRATED THEIR MODEL BY APPLYING IT TO A DATASET OF AIR POLLUTION ACROSS SAUDI ARABIA. view more 

CREDIT: © 2022 KAUST; MORGAN BENNETT SMITH.

By adapting a flow-following physical framework to the statistical modeling of large spatio–temporal datasets, KAUST researchers have developed a more robust and realistic general method for dealing with wind-driven phenomena. The approach promises to greatly improve the accuracy of pollutant dispersion prediction by incorporating more physically realistic processes into geostatistical modeling.

Geostatistical analyses involve the statistical processing of very large datasets, such as measurements of wind speed at many locations and altitudes over time, to extract an underlying model of how certain parameters behave and are correlated spatially and temporally in the real world. However, the ability of such models to accurately characterize that behavior and predict “what happens next” largely depends on the model framework used for analysis. A team of KAUST scientists led by Marc Genton has been developing more physically meaningful analytical frameworks that can better model such natural phenomena.

 

“Many space-time geostatistical models do not necessarily reflect fundamental scientific relationships,” explains Mary Salvaña, who worked with Genton and Amanda Lenzi on the research. “There is demand for space–time geostatistical models with a physics basis, as most environmental data obey various fundamental laws of nature. In this study, we took a modeling concept in physics called the Lagrangian framework and formulated it in the language of space–time multivariate geostatistics to develop a suite of data-driven space–time models that are more appropriate for datasets involving transport by media, such as wind.”

 

Wind is a complicated driving phenomenon to incorporate into a practical statistical model. It is asymmetric in its correlation, flowing from one place to another, and also varies by altitude. The Lagrangian framework was developed in the field of fluid dynamics to model flows in a way that is analogous to the underlying physics by following a fluid parcel as it moves through space and time. For Salvaña and her colleagues, the challenge was to ensure that this framework could be validly used with a space–time geostatistics model across multiple variables.

 

“Our results, which confirmed the validity of the model, showed that failing to account for multiple advections or transport phenomena can lead to poor predictions,” says Salvaña.

 

The team demonstrated their model by applying it to a bivariate pollutant dataset of particulate matter across Saudi Arabia. The results showed that black carbon distributions are much more accurately modeled taking altitude-dependent wind behavior into account.

 

“Our modeling framework could also be applied to the study of space–time correlation of ocean variables, since water is another transport medium, which could be important for understanding ocean patterns before and after a tropical cyclone,” Salvaña says.

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JOURNAL

Journal of the American Statistical Association

DOI

10.1080/01621459.2022.2078330 

ARTICLE TITLE

Spatio-Temporal Cross-Covariance Functions under the Lagrangian Framework with Multiple Advections

Study: Inflation of online ratings can be beneficial and detrimental

Peer-Reviewed Publication

CARNEGIE MELLON UNIVERSITY

Many adults consult online ratings and reviews before they make a purchase. However, how do ratings affect sales is a challenging topic as evidenced from controversy surrounding Rotten Tomato scores or sellers trying to manipulate ratings on various platforms. A new study investigates how rating inflation affected a digital platform as well as the choices users made. The study found that inflation can have benefits and detriments: While sales rose, users’ trials declined, and sales were concentrated among popular sellers. Rating inflating is when platforms change their strategy to increase average ratings. So, users see higher ratings for all restaurants.

The study, by researchers at Carnegie Mellon University (CMU) and the University of British Columbia, appears in Information Systems Research.

“Overall, our results illustrate the potential consequences of rating inflation that platforms need to consider when designing and managing their rating systems,” says Rahul Telang, professor of information systems and management at CMU’s Heinz College, who coauthored the study.

In the process of rating inflation, the variance across restaurants do down – since restaurants tend to have higher ratings, they look more similar. For instance, on eBay, the median seller might have a 100 percent positive rating, while the seller in the bottom 10th percentile has a 98 percent positive rating. Not only are these exceptionally high positive ratings, but there is little variation between good and mediocre sellers, making the overall ratings less informative for consumers.

In this study, researchers conducted an experiment with a digital food-delivery platform in a large Asian city that changed its rating in a neighborhood (with 48 restaurants on the platform), which resulted in rating inflation. They examined the impact of this change over 13 weeks in mid-2017 on users’ purchases, trials of new restaurants, and sales concentration in the context of choosing restaurants on the platform.

The study found that the platform benefitted from one aspect of rating inflation: Because this type of inflation makes sellers’ products appear to be of higher quality, both users’ purchases and sellers’ sales increased in the short term due to increased average ratings.

However, there were also negative consequences: The decrease in rating variance reduced the informativeness of ratings, which increased the uncertainty of users’ perceptions of restaurants’ quality and made them less likely to try a new establishment. Since perceptions of ratings were less certain, they became less important in shaping users’ perceptions of quality, and this boosted the importance of other signals (e.g., prior beliefs, prior experience), leading to a greater concentration of sales among popular restaurants.

Among the study’s limitations, the authors note they did not investigate the long-term effects of rating inflation. In addition, their data are from one city, limiting the generalizability of their results.

“Our findings offer important insights about the tradeoffs of rating inflation for managers, designers, and developers of digital platforms that use ratings to help users choose among numerous sellers,” suggests Hui Li, associate professor of marketing at CMU’s Tepper School of Business, who coauthored the study. “Such individuals should build informativeness into the design of rating systems to account for and minimize rating inflation on their platforms.”

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Summarized from an article in Information Systems Research, The Consequences of Rating Inflation on Platforms: Evidence from a Quasi-Experiment by Aziz, A (University of British Columbia), Li, H (Carnegie Mellon University), and Telang, R (Carnegie Mellon University). Copyright 2022. All rights reserved.

 

 

About Heinz College of Information Systems and Public Policy
The Heinz College of Information Systems and Public Policy is home to two internationally recognized graduate-level institutions at Carnegie Mellon University: the School of Information Systems and Management and the School of Public Policy and Management. This unique colocation combined with its expertise in analytics set Heinz College apart in the areas of cybersecurity, health care, the future of work, smart cities, and arts & entertainment. In 2016, INFORMS named Heinz College the #1 academic program for Analytics Education. For more information, please visit www.heinz.cmu.edu.

 

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JOURNAL

Information Systems Research

GIST scientists develop model that adjusts videogame difficulty based on player emotions

The novel approach will help create a better gaming experience for all types of players

Peer-Reviewed Publication

GIST (GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY)

 

IMAGE: THE NOVEL APPROACH TO DYNAMIC DIFFICULTY ADJUSTMENT (DDA) TAKES INTO ACCOUNT THE PLAYER'S EMOTIONS DURING GAMEPLAY INSTEAD OF THE PLAYER'S PERFORMANCE TO PROVIDE A BETTER PLAYER EXPERIENCE. view more 

CREDIT: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY

Difficulty is a tough aspect to balance in video games. Some people prefer videogames that present a challenge whereas others enjoy an easy experience. To make this process easier, most developers use ‘dynamic difficulty adjustment (DDA).’ The idea of DDA is to adjust the difficulty of a game in real time according to player performance. For example, if player performance exceeds the developer’s expectations for a given difficulty level, the game’s DDA agent can automatically raise the difficulty to increase the challenge presented to the player. Though useful, this strategy is limited in that only player performance is taken into account, not how much fun they are actually having.

In a recent study published in Expert Systems With Applications, a research team from  the Gwangju Institute of Science and Technology in Korea decided to put a twist on the DDA approach. Instead of focusing on the player’s performance, they developed DDA agents that adjusted the game’s difficulty to maximize one of four different aspects related to a player’s satisfaction: challenge, competence, flow, and valence. The DDA agents were trained via machine learning using data gathered from actual human players, who played a fighting game against various artificial intelligences (AIs) and then answered a questionnaire about their experience.

Using an algorithm called Monte-Carlo tree search, each DDA agent employed actual game data and simulated data to tune the opposing AI’s fighting style in a way that maximized a specific emotion, or ‘affective state.’ “One advantage of our approach over other emotion-centered methods is that it does not rely on external sensors, such as electroencephalography,” comments Associate Professor Kyung-Joong Kim, who led the study.  “Once trained, our model can estimate player states using in-game features only.”

The team verified—through an experiment with 20 volunteers—that the proposed DDA agents could produce AIs that improved the players’ overall experience, no matter their preference. This marks the first time that affective states are incorporated directly into DDA agents, which could be useful for commercial games. “Commercial game companies already have huge amounts of player data. They can exploit these data to model the players and solve various issues related to game balancing using our approach,” remarks Associate Professor Kim. Worth noting is that this technique also has potential for other fields that can be ‘gamified,’ such as healthcare, exercise, and education.

This paper was made available online on June 3, 2022, and will be published in Volume 205 of the journal on November 1, 2022.

Let us hope this study paves the way to games that any type of player, whether hardcore or casual, can enjoy!

 

***

 

Reference

DOI: https://doi.org/10.1016/j.eswa.2022.117677

Authors: JaeYoung Moon1, YouJin Choi2, TaeHwa Park2, JunDoo Choi1, Jin-Hyuk Hong2, Kyung-Joong Kim*2

Affiliations:      
1Graduate School of Artificial Intelligence, Gwangju Institute of Science and Technology

2School of Integrated Technology, Gwangju Institute of Science and Technology

 

About the Gwangju Institute of Science and Technology (GIST)
The Gwangju Institute of Science and Technology (GIST) is a research-oriented university situated in Gwangju, South Korea. Founded in 1993, GIST has become one of the most prestigious schools in South Korea. The university aims to create a strong research environment to spur advancements in science and technology and to promote collaboration between international and domestic research programs. With its motto of “A Proud Creator of Future Science and Technology,” GIST has consistently received one of the highest university rankings in Korea.

Website: http://www.gist.ac.kr/

 

About the authors
Kyung-Joong Kim is an Associate Professor at the Institute of Integrated Technology and Chief of the Game AI Center in Gwangju Institute of Science and Technology (GIST), South Korea. His group is developing human-centered game AI to enhance the gaming experience of human players. Before joining GIST, he served as an associate professor in computer engineering at Sejong University for 10 years. He completed his postdoctoral training at Lipson’s Lab at Cornell University, USA.

JaeYoung Moon is a PhD student at Kim’s lab at GIST.

YouJin Choi is a PhD student at Hong’s lab at GIST.

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JOURNAL

Expert Systems with Applications

DOI

10.1016/j.eswa.2022.117677 

METHOD OF RESEARCH

Computational simulation/modeling

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Diversifying dynamic difficulty adjustment agent by integrating player state models into Monte-Carlo tree search

ARTICLE PUBLICATION DATE

1-Nov-2022

Isle Royale Winter Study finds wolves living their best lives, moose not so much

Reports and Proceedings

MICHIGAN TECHNOLOGICAL UNIVERSITY

 

IMAGE: TWO PUPS FROM THE EASTERN PACK TRY TO ROUSE PACKMATES FOR PLAY. view more 

CREDIT: SARAH HOY

Key findings include:

• A doubling of the wolf population, now estimated at 28 total wolves. “Each time we carried out aerial surveys this winter, we saw wolf tracks across many parts of the island and we also regularly saw groups of wolves traveling or resting together,” said Hoy. “It is such a pleasant change from five years ago when there were only two wolves on the island and the future of the wolf population looked pretty bleak. It just goes to show how quickly wolf populations are able to thrive in places where they are free from persecution.”

• A 28% decline in the moose population, from 1,876 to 1,346. Wolf kills accounted for 8.7% of the moose mortalities, the highest predation rate since 2011. Other challenges for the moose include blood-sucking winter ticks that weaken the animals, and spruce budworm infestations that kill balsam fir, their preferred winter food. “Over the past year we found an unusually high number of moose that appear to have died due to malnutrition,” Hoy said. “The population appears to be suffering from a food shortage, especially in winter when moose don’t have many good options of things to eat.”

For more information and to access the Winter Study report, read the full story at MTU News.

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About Michigan Technological University

Michigan Technological University is a flagship technological public research university founded in 1885 in Houghton, Michigan. The University offers more than 125 undergraduate and graduate degree programs in science and technology, engineering, computing, forestry, business and economics, health professions, humanities, mathematics, social sciences, and the arts. The rural campus is situated just miles from Lake Superior in Michigan’s Upper Peninsula and is home to more than 7,000 students.

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METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Ecological Studies of Wolves on Isle Royale

A bull moose, outfitted with a GPS collar near Beaver Island at the west end of Isle Royale in February 2022, shown having lost or damaged large patches of its winter coat, especially near the shoulder region. This bull died on 14 April 2022, seemingly from malnutrition.

CREDIT

Sarah Hoy

A large group of wolves were seen feeding on a moose on the ice near Daisy Farm at the east end of the Isle Royale National Park on 7 February. After that large group of wolves had left the area, Ky and Lisa Koitzsch visited the kill site to determine the age and sex of the dead moose and to collect scat samples from wolves for genetic analysis.

CREDIT

Ky and Lisa Koitzsch

Research reveals potentially life-changing impact of internet forums on those in remission from opioid use disorder

Peer-Reviewed Publication

UNIVERSITY OF EXETER

Active participation in internet forums has the potential to provide life-changing social benefits and wellbeing for people who are in remission from opioid use disorder.

Engaging with online communities, particularly those of a generalist nature unconnected to drug and addiction topics, can help people accrue invaluable ‘social capital’ that dramatically reduces the risk of them having a use episode during remission.

Paradoxically, being overly focused upon forums dedicated to therapy and support can in some circumstances have a negative effect, making it more likely that a person will report a use episode during remission.

These insights, arising from new research by the University of Exeter, could have significant public health implications, particularly for those who are less able or willing to engage in traditional in-person recovery and rehabilitation programmes. 

Published in the Journal of Medical Internet Research, the paper, Effects of Substance Use, Recovery, and Non–Drug-Related Online Community Participation on the Risk of a Use Episode During Remission From Opioid Use Disorder: Longitudinal Observational Study, highlights the ongoing benefits that online forums can provide many years into a person’s remission journey.

“Opioid addiction is one of the most pressing public health issues of the day,”

said research lead Dr Miriam Koschate-Reis, Associate Professor of Computational Social Psychology, in the Faculty of Health and Life Sciences.

“Whether it is addiction to prescription drugs such as painkillers, illicitly manufactured synthetic opioids such as fentanyl, or opiates including heroine, the human cost is profound.

“The provision of therapy and recovery support groups is an important step in addressing this issue, but there can barriers to accessing these services such as a lack of funding, stigma, and personal circumstances. This research highlights the impact that online groups, such as forums on popular platforms like Reddit can have. The results suggest that they may provide a lifeline for those who are in remission from opioid use disorder.”

The research team used the popular news and discussion site Reddit as the basis for the research and began by focusing upon one of its dedicated forums – or subreddits – called ‘OpiatesRecovery’. More than 31,000 members have used this forum since 2012, which offers peer support and recovery information, with many regularly making statements about their remission status, such as the number of days since they last used opioids. 

After an extensive process of data cleaning, a sample of 457 individuals was formalised, 48% of whom had reported opiate or opioid use during remission during their time on the forum, and 52% who had not. Through analysis of unique and anonymous user IDs, the researchers were able to track activities across the entire Reddit platform, enabling them to construct a picture of which other types of Reddit subforums they were engaging with. 

From this, they identified more than 1,200 subreddits, which they categorised into those that related to substance use, those devoted to recovery support, and those unrelated to either. They then recorded the number of posts and comments each participant had contributed during the 2012—2019 timeframe.

“Our findings showed that the greater the number of online non–drug-related groups an individual recovering from opioid use disorder became a part of, the lower the risk of a use episode over time,”

said Dr Elahe Naserianhanzaei, co-researcher in the Faculty of Humanities, Arts and Social Sciences.

“Indeed, this could be as much as a 5% reduction per subforum. And this effect persisted when membership in recovery and substance use groups was also accounted for. This is in line with the view that social groups deliver health benefits and create resilience.”

The findings also revealed several other notable trends that could warrant further research. The first was that while there was a benefit to engaging with forums devoted to recovery, there was a correlation between those who focused more narrowly upon such sites and those at risk of opioid use during remission. 

Secondly, participation in forums that focused on substance use was not associated with an increased risk of an opioid use episode, suggesting that online interactions with people who discuss substance use may not necessarily be harmful for those in remission.

Furthermore, the researchers found that there was some correlation between an increased amount of posting activity in recovery and general interest forums, and risk of a use episode during remission - something that the authors say warrants further examination.

“Our longitudinal study of online behaviour over six years gives us an insight into a much longer period of recovery than has previously been focused upon,”

added Dr Koschate-Reis.

“It provides the first indication that a person’s remission journey needs to continue beyond the phase where they build recovery support group memberships and move towards group participation that is non-drug related. And these results indicate that online communities can help people to make that transition.”

The study, Effects of Substance Use, Recovery, and Non–Drug-Related Online Community Participation on the Risk of a Use Episode During Remission From Opioid Use Disorder: Longitudinal Observational Study, was funded by the Engineering and Physical Sciences Research Council, and is available to download for free at https://www.jmir.org/2022/8/e36555

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JOURNAL

Journal of Medical Internet Research

DOI

10.2196/36555 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Effects of Substance Use, Recovery, and Non–Drug-Related Online Community Participation on the Risk of a Use Episode During Remission From Opioid Use Disorder: Longitudinal Observational Study

Increasing impacts of floods and droughts worldwide

How to improve natural risk management

Peer-Reviewed Publication

UNIVERSITY OF BARCELONA

Risk management has reduced the vulnerability to floods and droughts around the world, but their impact is still increasing worldwide, according to a study published in the journal Nature, which includes the participation of the researcher María del Carmen Llasat, professor of Atmospheric Physics at the Faculty of Physics and member of the Water Research Institute (IdRA) of the University of Barcelona.

This intensification of the impact of natural phenomena is particularly noticeable when the second event —rain, floods or droughts— affecting the same region has a higher degree of hazard —more intensity and magnitude— than the first previously recorded event.

“This results from the fact that the improvement in management has been based on the parameters of previous episodes, but it has not been designed to cope with such extreme events. The difficulty observed in managing unprecedented events is alarming, especially if we consider that, as a result of the climate change, the hydrological events that are projected are becoming increasingly extreme”, notes Llasat, who received the Saint George’s Cross this year for her scientific career in the field of physics and for the study, research and awareness of climate change and natural hazards.

Flood and drought episodes worldwide

The study, led by the expert Heidi Kreibich, from the German Research Centre for Geosciences (GFZ), includes the participation of nearly a hundred experts from the International Association of Hydrological Sciences (IAHS).

The study analyses 29 pairs of flood episodes and 15 cases drought episodes in different areas of the world. The aim is to check how these factors involved in risk have changed between the first and the second episode, generally occurring more than ten years apart, but in the same place.

In the case of Catalonia, the study compared pluvial floods in Barcelona that occurred on 21 September 1995 and on 6 September 2018, and the recorded droughts in the periods 1986-1989 and 2004-2008. To carry this comparative analysis out, in the case of the rainfalls, the researchers worked in collaboration with Barcelona Water Cycle (BCASA) —entity in charge of the pluvial rain management in Barcelona—, and regarding the droughts, they worked in collaboration with the Ebro Observatory (URL-CSIC).

Barcelona city, a successful case

The international study has recorded only two success stories —Barcelona and Central Europe— in natural hazard management, out of the 29 pairs of flood events analysed worldwide. In these cases, the hazard of the second recorded event was higher than that of the first, but the recorded damage was lower.

In the case of Barcelona, following the 1996 floods, the city promoted a plan that culminated in the construction of 15 rainwater retention basins and the improvement of the entire flood prevention and management system.

"The improvements in Barcelona's rainwater network over the last twenty years have been decisive in alleviating the effects of floods in the city. In fact, while in the Metropolitan Area of Barcelona there has been a slight increase in flooding since 1981, this trend is negative in Barcelona. However, this is not enough", notes Llasat, member of the Department of Applied Physics and head of the Group for the Analysis of Adverse Meteorological Situations (GAMA).

"The permeability of the soil should be increased with paving that allows rain to filter through, more areas should be set aside for green spaces and streets and drains should be kept clean. However, there are still neighbourhoods with major flooding problems where it is difficult to take structural action, such as storm water tanks. In these cases, it is necessary to look for solutions that require citizen participation and awareness of this type of event. Specifically, this is the challenge now faced by the I-CHANGE (Individual Change of HAbits Needed for Green European transition) project, funded with Horizon 2020 funds and in which the University of Barcelona is participating.

Flood management in Germany and Austria is the other success story described in the article. Two common factors stand out in the successful strategies of Barcelona and Central Europe: the improvement of risk management governance —more integration in emergency management and early warning systems— and the implementation of a series of structural measures that required high investment (the storm water reservoirs in Barcelona or the construction of dykes in Central Europe).

How to improve natural risk management?

Efforts to promote more operational and effective responses to these extreme events face a number of obstacles. "Large investments such as those made in the city of Barcelona or in Central Europe are not possible for everyone. In fact, they would not be desirable either. Recent studies have shown that they can lead to a false sense of security (especially in the case of river flooding), as they increase the occupation of flood zones and thus the associated risk”.

“Despite structural improvements —she continues—, "the United Nations consider that Barcelona is not doing enough to raise awareness of the risk of flooding among its inhabitants, nor among visiting people. This is a widespread problem", Llasat points out.

Improving governance, applying nature-based solutions and involving citizens are the global key actions for mitigating the effects of natural hazards worldwide, in a context of sustainable development.

"It is necessary for the Administration to improve its knowledge of risk, the distribution of the most flood-prone areas in the city, how to act when there are heavy rains, etc. Regarding the citizens, it is necessary to become aware that this risk will increase with climate change and that we will need citizen participation. Education in schools, compulsory information on flood risks, improved warnings to the population and guidelines on how to act both preventively and during the emergency are also some of the points that should be considered to reduce the impact of these natural events", concludes Professor Llasat.

 

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JOURNAL

Nature

DOI

10.1038/s41586-022-04917-5 

METHOD OF RESEARCH

Meta-analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

The challenge of unprecedented floods and droughts in risk management

Young children who walk or bike to school are more likely to continue the habit as they age

Smarter urban design can help encourage ‘active commuting,’ Rutgers researcher says

RUTGERS UNIVERSITY

Children who walk or bike to school at a young age are more likely to continue the healthy habit as they age, according to a study co-authored by a Rutgers researcher.

“The walk to school is a wonderful moment in the day that provides children a glimpse of living an active lifestyle,” said David Tulloch, a professor of landscape architecture at Rutgers–New Brunswick and co-author of the study, which was published in the journal Preventive Medicine Reports. “When people start walking early, it can have a lasting impact on their health.”

In the United States, about 11 percent of children walked or biked to or from school, according to data from the National Household Travel Survey, and that rate hasn’t changed in a decade.

The research team found that if children are taught early to actively commute – traveling by physical means – they are far more likely to keep doing so later in their educational career.

To measure whether active commuting persists over time, the researchers surveyed parents and caregivers about the school travel habits of their children on two separate occasions two to four years apart (baseline and follow-up) between 2009 and 2017 in four predominantly low-income New Jersey cities: Camden, New Brunswick, Newark and Trenton.

Data from 587 households was collected as part of the New Jersey Child Heath Study, which tracked children 3-15 years of age. The distance to school and other spatial factors were calculated by Tulloch and colleagues at the Grant F. Walton Center for Remote Sensing and Spatial Analysis at Rutgers.

The researchers found that more than three quarters of children who engaged in active commuting at baseline continued to do so two to four years later, while few newly took it up by the time of follow-up if they hadn’t done so before.  In fact, children who actively commuted to school at baseline were seven times more likely to actively commute two to four years later compared with children who didn’t actively commute at baseline.

“Most kids don't achieve the 60 minutes per day of physical activity that they're recommended to get,” said Robin DeWeese, an assistant research professor in the College of Health Solutions at Arizona State and the study’s lead author. “Active commuting to school is one way to get more of that activity.”

To promote active commuting, DeWeese suggests “schools and communities encourage active commuting during early grades as that may yield benefits even for students in higher grades.”

Active commuting varied by demographic characteristics and perceptions of the neighborhood. Children with a parent born outside the U.S. had lower odds of active commuting compared with those whose parents were born in the U.S., while children of parents who perceived their neighborhood safe from crime were more than 2.5 times as likely to engage in active commuting.

The greatest and most persistent barrier was the distance between home and school, Tulloch said. Distance to school often increases as children age because middle and high schools are larger and less prominent than elementary schools. As a result, active commuting likelihood tends to decrease once children reach high school.

Smarter urban design can help reverse this trend, said Tulloch. Remote drop-offs and “walking school buses” – that is, groups of students chaperoned by volunteer parents – can encourage children to actively commute at a young age. Infrastructure improvements, such as sidewalks and tree-lined streets, can make walking more pleasant, he added.

“One of the most visited tourist sites in New York City is the High Line, a green walkable space with no cars,” said Tulloch. “We should be doing this type of planning everywhere – especially in school zones.”

Novel technique helps discover whether bacteria that cause meningitis are resistant to antibiotics

The results of a study conducted by Brazilian researchers will be useful both for epidemiological surveillance and to improve the treatment available to patients. An article on the study is published in PLOS ONE.

Peer-Reviewed Publication

FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO

 

IMAGE: IT CAN BE USED TO STUDY THE RESISTANCE PROFILE OF PNEUMOCOCCUS EVEN IN THE ABSENCE OF THE ISOLATED STRAINS (PNEUMOCOCCI OBSERVED IN THE MICROSCOPE) view more 

CREDIT: IVANA CAMPOS

A study published in the journal PLOS ONE could one day help health workers determine whether bacteria of the species Streptococcus pneumoniae, which cause meningitis – an inflammation of the membranes that envelop the brain and spinal cord – are resistant to antibiotics.

This type of analysis is no easy task when the conventional method is used. The bacteria must be isolated from a patient sample and analyzed while still alive, which is difficult because the microorganisms are sensitive and usually do not survive the journey to the laboratory.

A highly feasible novel method has been developed in Brazil by researchers at the Santo André branch of Adolfo Lutz Institute (IAL), São Paulo state's central epidemiological surveillance laboratory. Between 2014 and 2020, they analyzed 873 samples of cerebrospinal fluid from patients with suspected streptococcal meningitis at health clinics in six cities in the state – Diadema, Mauá, Santo André, São Bernardo do Campo, São Caetano do Sul and Ribeirão Pires. Cerebrospinal fluid is produced by tissue that lines the ventricles in the brain. It flows in and around the brain and spinal cord to cushion them from injury and provide nutrients. 

As part of the laboratory’s routine, the scientists analyzed the samples using real-time PCR, the gold standard for diagnosing infectious diseases, including COVID-19. The technique amplifies a specific gene or gene sequence from the target microorganism, if present in the sample, so that it can be identified more easily. In this case, S. pneumoniae (pneumococcus) was detected in 149 samples.

They then re-analyzed the samples that tested positive for pneumococcus to detect the three genes associated with resistance to antibiotics, again using real-time PCR but this time with SYBR Green, a dye that binds to DNA and emits a fluorescent signal which is captured by the equipment. 

To find out which classes of antibiotics the bacteria resisted – penicillin, lincosamides or macrolides – they used the dissociation curve technique. “This technique entails raising the temperature of the samples degree by degree, making the dye separate from the DNA as the twin strands in the double helix forming the genetic material amplified in the PCR machine gradually unwind. We measured the melting temperature [Tm], which is when half the structure is still entwined and the rest has separated out. This temperature varies depending on the amplified gene, so it can be used to identify the gene that’s been amplified and hence the antibiotic to which the bacteria are resistant,” said Ivana Campos, principal investigator for the study. 

After conducting all these procedures, the researchers compared the results with those obtained by the conventional method used to analyze resistance to antibiotics, in which live bacteria are observed while in contact with each drug to see if they are able to proliferate. This conventional test was performed on 25 samples, which were the only ones that contained viable pneumococci for the procedure. The results were similar, confirming the novel technique’s potential. 

“We found that 51% of the samples analyzed, which IAL received between 2014 and 2020, were sensitive to antibiotics. That’s positive, meaning these patients must have had a good prognosis. On the other hand, 17% were resistant to various drugs, which is very dangerous because in these cases it’s more difficult to treat the disease and other classes of antibiotic have to be tried,” Campos said. 

Moreover, S. pneumoniae is capable of changing its genetic makeup as it reproduces, so that new copies have the genes associated with drug resistance. “We, therefore, concluded that the test we developed can be used to study the resistance profile of pneumococcus even in the absence of the isolated strains, as evidenced for our region,” she said.

The study was supported by FAPESP via two projects (17/03022-6 and 18/22718-4. The results obtained will be useful both for epidemiological surveillance and to improve treatment of patients in future.

About São Paulo Research Foundation (FAPESP)

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe

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JOURNAL

PLoS ONE

DOI

10.1371/journal.pone.0269895 

ARTICLE TITLE

Multiplex real-time PCR using SYBR Green: Unspecific intercalating dye to detect antimicrobial resistance genes of Streptococcus pneumoniae in cerebrospinal fluid