Aquatic ecosystems source of half of global methane emissions

YALE SCHOOL OF THE ENVIRONMENT

Research News

 

Direct human alterations to natural aquatic ecosystems can increase methane emissions, a new study has found.

Atmospheric methane has tripled since pre-industrial times. It traps heat far more effectively than carbon dioxide and accounts for 25% of atmospheric warming to date. And much of that methane is coming from aquatic ecosystems, with human activities contributing to the emissions levels, a new paper published in Nature Geoscience has found.

The global contribution and importance of aquatic ecosystems as methane emitters has been underestimated, says Judith Rosentreter, postdoctoral associate at the Yale School of the Environment (YSE) who led the study with a team of 14 researchers worldwide.

The study authors reviewed methane fluxes from 15 major natural, human-made, and human-impacted aquatic ecosystems and wetlands, including inland, coastal, and oceanic systems. They found that when methane emissions are combined from these aquatic ecosystems, they are potentially a larger source of methane than direct anthropogenic methane sources, such as agriculture or fossil fuel combustion. Aquatic ecosystems and wetlands contribute at least as much as half of the total methane emissions budget.

"An accurate accounting of the sources of methane from aquatic ecosystems, and if they are impacted by human activities, is important to understanding atmospheric methane concentrations,'' says Peter Raymond, professor of ecosystem ecology who co-authored the study.

One issue that stood out is how humans have impacted methane emissions from aquatic sources.

"Anything human-driven or human-impacted had much higher fluxes than more natural sites,'' says Rosentreter, a Yale Institute for Biospheric Studies Hutchinson Fellow.

Globally, rice cultivation releases more methane per year than all coastal wetlands, the continental shelf and open ocean combined. Fertilizer runoff causes nutrient-rich lakes and reservoirs to release methane. Coastal aquaculture farms have methane fluxes per area that are 7-430 times higher than from non-converted coastal habitats, such as mangrove forests, salt marshes or seagrasses.

But the study notes that there are opportunities to reduce human-impacted emissions with the right management techniques.

"The intense methane emissions from aquatic ecosystems offers opportunities for intervention providing potential quick wins in reducing greenhouse emissions, provided the much large role per molecule emitted of methane compared to carbon dioxide,'' says study co-author Carlos M. Duarte, professor at King Abdullah University of Science and?Technology (KAUST) in Saudi Arabia.

Fluctuating between flooded and non-flooded conditions in aquaculture farms and rice paddies; restoring tidal flow in degraded coastal wetlands; and reducing nutrient and organic matter in freshwater lakes, reservoirs, and rivers can all help reduce emissions, the study notes.

"Reducing methane emissions from aquatic systems will be an important part of stabilizing the Earth's temperature,'' says co-author Bradley Eyre Director, Centre for Coastal Biogeochemistry at Southern Cross University in Australia.

Bringing awareness to the amount of methane emissions coming from aquaculture and other water systems can help inform new monitoring and measurements that identify where and how methane emissions are being produced and change over time.

"With this awareness is also the possibility of helping to keep our waters cleaner,'' Rosentreter says.

###

 

Scientists harness chaos to protect devices from hackers

New tech packs computer chips with "uncountable" secrets

OHIO STATE UNIVERSITY

Research News

 

COLUMBUS, Ohio - Researchers have found a way to use chaos to help develop digital fingerprints for electronic devices that may be unique enough to foil even the most sophisticated hackers.

Just how unique are these fingerprints? The researchers believe it would take longer than the lifetime of the universe to test for every possible combination available.

"In our system, chaos is very, very good," said Daniel Gauthier, senior author of the study and professor of physics at The Ohio State University.

The study was recently published online in the journal IEEE Access.

The researchers created a new version of an emerging technology called physically unclonable functions, or PUFs, that are built into computer chips.

Gauthier said these new PUFs could potentially be used to create secure ID cards, to track goods in supply chains and as part of authentication applications, where it is vital to know that you're not communicating with an impostor.

"The SolarWinds hack that targeted the U.S. government really got people thinking about how we're going to be doing authentication and cryptography," Gauthier said.

"We're hopeful that this could be part of the solution."

The new solution makes use of PUFs, which take advantage of tiny manufacturing variations found in each computer chip - variations so small that they aren't noticeable to the end user, said Noeloikeau Charlot, lead author of the study and a doctoral student in physics at Ohio State.

"There's a wealth of information in even the smallest differences found on computers chips that we can exploit to create PUFs," Charlot said.

These slight variations - sometimes seen only at the atomic level - are used to create unique sequences of 0s and 1s that researchers in the field call, appropriately enough, "secrets."

Other groups have developed what they thought were strong PUFs, but research showed that hackers could successfully attack them. The problem is that current PUFs contain only a limited number of secrets, Gauthier said.

"If you have a PUF where this number is 1,000 or 10,000 or even a million, a hacker with the right technology and enough time can learn all the secrets on the chip," Gauthier said.

"We believe we have found a way to produce an uncountably large number of secrets to use that will make it next to impossible for hackers to figure them out, even if they had direct access to the computer chip."

The key to creating the improved PUF is chaos, a topic that Gauthier has studied for decades. No other PUFs have used chaos in the way demonstrated in this study, he said.

The researchers created a complex network in their PUFs using a web of randomly interconnected logic gates. Logic gates take two electric signals and use them to create a new signal.

"We are using the gates in a non-standard way that creates unreliable behavior. But that's what we want. We are exploiting that unreliable behavior to create a type of deterministic chaos," Gauthier said.

The chaos amplifies the small manufacturing variations found on the chip. Even the smallest differences, when amplified by chaos, can change the entire class of possible outcomes - in this case, the secrets that are being produced, according to Charlot.

"Chaos really expands the number of secrets that are available on a chip. This will likely confuse any attempts at predicting the secrets," Charlot said.

One key to the process is letting the chaos run just long enough on the chip, according to Gauthier. If you let it run too long, it becomes - well, too chaotic.

"We want the process to run long enough to create patterns that are too complex for hackers to attack and guess. But the pattern must be reproducible so we can use it for authentication tasks," Gauthier said.

The researchers calculated that their PUF could create 1077 secrets. How big is that number? Imagine if a hacker could guess one secret every microsecond - 1 million secrets per second. It would take the hacker longer than the life of the universe, about 20 billion years, to guess every secret available in that microchip, Gauthier said.

As part of the study, the researchers attacked their PUF to see if it could be successfully hacked. They attempted machine learning attacks, including deep learning-based methods and model-based attacks - all of which failed. They are now offering their data to other research groups to see if they can find a way to hack it.

Gauthier said the hope is that PUFs like this could help beef up security against even state-sponsored hacker attacks, which are generally very sophisticated and backed up with a lot of computer resources.

For example, Russia is suspected of backing the SolarWinds hack that was uncovered in December. That hack reportedly gained access to email accounts of officials in the Department of Homeland Security and the department's cybersecurity staff.

"It is a constant battle to come up with technology that can stay ahead of hackers. We are trying to come up with technology that no hacker - no matter your resources, no matter what supercomputer you use - will be able to crack."

The researchers have applied for an international patent for their PUF device.

The goal of the team is to move beyond research and to move quickly to commercialize the technology. Gauthier and two partners recently founded Verilock, with a goal of bringing a product to market within a year.

"We see this technology as a real game changer in cybersecurity. This novel approach to a strong PUF could prove to be virtually un-hackable," said Jim Northup, CEO of Verilock.

###

The work was supported in part by the U.S. Department of the Army with Potomac Research, LLC, through the project Physically Unclonable Functions on FPGAs, and by the Ohio Federal Research Network with Asymmetric Technologies, LLC and Ohio University, through the project Resilient and Enhanced Security UAS Flight Control.

Other co-authors on the study were Daniel Canaday and Andrew Pomerance of Potomac Research in Alexandria, Virginia.

 

A study by UPF analyses for the first time in Spain the effect of sexual orientation on wages

The research, led by María José González and İbrahim Sönmez, studies the relationship between wages and type of partner (homosexual and heterosexual) for men and women between 2006 and 2018

UNIVERSITAT POMPEU FABRA - BARCELONA

Research News

 

Spain is among the five countries in the world with the highest levels of social acceptance of LGBTIQ+ people and rights, and was the third country in the world to legalize same-sex marriages, in 2005. In 2019, 3.1% of marriages were between same-sex couples (INE 2020). In this context, it would seem consistent that sexual orientation should not determine wage inequalities. But is this really so? What is the relationship between sexual orientation and wages?

The study, recently published in Journal of Family Issues, found a significant correlation between sexual orientation -measured on the basis of type of partner- and wages.

A study led by María José González, a professor at the UPF Department of Political and Social Sciences and a researcher with the Sociodemography Research Group (DemoSoc), together with ?brahim Sönmez, a predoctoral researcher and member of the same group, has analysed for the first time in Spain whether sexual orientation leads to salary differences between men and women who live with a partner.

The study, recently published in Journal of Family Issues, finds a significant correlation between sexual orientation -measured on the basis of type of partner- and wages, despite the degree of tolerance of LGBTIQ+ rights.

The labour market discriminates against partnered homosexual men

M. José González asserts that "our results show that partnered gay men suffer a wage disadvantage compared to partnered heterosexuals under this model. And this disadvantage remains present even after taking sociodemographic differences into account such as the presence of children, educational attainment, occupational level, work experience or sector of employment (public and private)".

According to the authors, statistical analyses indicate that the wage gap due to men's sexual orientation can largely be attributed to unobservable variables, which would indicate the presence of discrimination against homosexuals in the labour market.

Partnered lesbians earn more money, due to their socio-occupational profile

Moreover, with regard to partnered women, the research finds that lesbians have a wage advantage compared to heterosexual women. However, this advantage disappears after controlling for differences in labour trends of women according to sexual orientation.

"Lesbians are less likely to undertake the bulk of household tasks and home care and, therefore, are also less susceptible to inactivity and part-time work than heterosexual women", M. José González explains. And she adds: "If, however, we take working hours into account, both lesbians and heterosexuals receive wages according to their training and work experience, regardless of their sexual orientation".

Analysis of data between 2006 and 2018 from the EPA labour force survey, the social security and tax agencies

The work is the first in its field in Spain, as for the first time a database is available that combines individual income and household make-up (EPA labour force survey with a sample of nearly 190,000 people) with wage data records from the social security and tax agencies. These data allow analysing the association between wages and type of partner (homosexual or heterosexual) for men and women in Spain between 2006 and 2018.

The authors identify people living with a same-sex partner (homosexual) and opposite sex partners (heterosexual).

The authors identify people living with a same-sex partner (homosexual) and opposite sex partners (heterosexual). In fact, they do not have a perfect indicator of sexual orientation of the population (these data are not usually available in official surveys) but an approximate or indirect variable obtained from the make-up by sex of couples (from questions such as whether they live with a partner and the sex of the partner).

Legislation must eliminate stereotypes and discrimination, which still exist

The work, which highlights the need to implement policies that work to eliminate stereotypes and prejudices towards different sexual orientations, stresses that in a seemingly open, tolerant society as is Spain, sexual orientation is still important. "Our study has shown that the transgression of the mandate of heteronormativity has consequences in the labour market for men, but not for women", M. José González asserts.

"Our study has shown that the transgression of the mandate of heteronormativity has consequences for the labour market for men, but not for women".

Moreover, the authors warn of "statistical discrimination", which mostly affects heterosexual women (and not so much lesbians, with higher wages): they are offered lower wages in the labour market not due to their personal characteristics, but due to the widespread perception that they are less productive due to the specialization of gender roles and the corresponding overload of housework and care.

Finally, there are some "unobserved characteristics", such as value or expectations, which may affect wage inequality between men and women in same-sex couples and couples of the opposite sex. "If a gay man expects to be discriminated against, his labour market expectations may be reduced. In this case, it is not sexual orientation that is responsible for wage inequality, but differences in ambition and expectations", M. José González concludes.

###

Reference article: M. José González, ?brahim Sönmez (March 2021). "Challenging Heteronormativity: An Analysis of the Effect of Sexual Orientation on Earnings in Spain". Journal of Family Issues

https://doi.org/10.1177/0192513X21993184

For chronic kidney disease, an ounce of prevention can be economical

University of Tsukuba study identifies a cost-effective way of getting health-care professionals to better manage treatment of chronic kidney disease and extend patients' lives

UNIVERSITY OF TSUKUBA

Research News

 

Tsukuba, Japan - With a prevalence of about one in 10 people worldwide, chronic kidney disease (CKD) is a global health problem. It also often goes undetected, leading to a range of negative health outcomes, including death. Catching it at an early stage and adjusting nutrition and lifestyle can improve and extend life, but only if there are economically feasible systems in place to promote and educate on this.

Amid finite health-care resources, any CKD intervention must be both practical and cost-effective. A team of researchers centered at the University of Tsukuba now believe they have found a CKD behavioral intervention that can be delivered at a reasonable cost. They published their findings in the Journal of Renal Nutrition.

Changing eating and lifestyle habits, and regularly visiting a doctor, are vital in managing CKD. Yet the CKD treatment guidelines under Japan's nationalized health-care system offer little economic incentive for general physicians (GPs) to recommend dietitians' valuable guidance for CKD patients.

"There's substantial evidence, including the Japanese Society of Nephrology's clinical guidelines, that dietitian-led patient education can slow the progression of CKD," study corresponding author Professor Masahide Kondo says. "But this sort of education seldom happens in Japan. We sought a way to justify such interventions and incentivize GPs to initiate them."

With a lack of economic assessments of these interventions, the researchers conducted a cost-effectiveness analysis using a Markov model, a mathematical method for finding patterns and making predictions. Based on results from the Frontier of Renal Outcome Modifications in Japan (FROM-J) study, which found success in dietitian-led education and lifestyle advice, along with periodic check-ups, they projected how such intervention would perform economically.

Naturally, a host of factors, such as disease progression and drug costs, play into this complex modeling. Key here was whether the incremental cost-effectiveness ratio (ICER), which shows the unit cost of gaining 1 extra healthy life year among the patients via the intervention, gave sufficient worth for that amount. The estimated ICER of about US$1,324 per quality-adjusted life year (QALY) was compared with the suggested social willingness to pay about US$45,455 for a 1-QALY gain. This demonstrates considerable cost-effectiveness.

"Diffusing such CKD interventions now seems justifiable, even with limited health-care resources," study first author Assistant Professor Reiko Okubo says. "We found that by adjusting the reimbursements and accessing the country's 5,000 registered dietitians, we could incentivize GPs to encourage practical behavioral interventions."

Behavior modification for CKD patients has the potential to be cost-effective within Japan's national health-care scheme. It can also improve and extend lives. Such findings could extend to other countries and encourage them to modify their guidelines. If policy can follow suit and GPs can comply with the advice, CKD can become a more manageable, and less fatal, disease.

###

The article, "Cost-Effectiveness of Behavior Modification Intervention for Patients With Chronic Kidney Disease in the FROM-J Study," was published in Journal of Renal Nutrition at https://doi.org/10.1053/j.jrn.2020.12.008

Japanese consumers more concerned about gene-editing of livestock than of vegetables, survey shows

RESEARCH ORGANIZATION OF INFORMATION AND SYSTEMS

Research News

 

IMAGE: PIG FARMING IN NORTHERN JAPAN view more 

CREDIT: PHOTO BY HISASHI URASHIMA

A statistically rigorous survey of Japanese consumers has found that they have more negative opinions about the use of new gene-editing techniques on livestock than they do about use of the same technologies on vegetables.

The survey findings were reported in the journal BMC CABI Agriculture and Bioscience on March 31st, 2021.

Because humans tend to feel closer to animals than plants, and commonly express feelings regarding animal welfare but not plant welfare, the researchers, led by Naoko Kato-Nitta, a research scientist at Tokyo's Joint Support Center for Data Science Research and Institute of Statistical Mathematics, wanted to see if such moral or taxonomic distinctions would produce any difference in their attitudes towards use of emerging gene-editing techniques such as CRISPR-Cas9.

Earlier surveys had shown subtle differences in consumer attitudes towards genetic modification, where foreign DNA is inserted into an organism's genome, compared to gene-editing, where an organism's genes are tweaked but no foreign DNA is introduced.

Via an online survey of just over 4,000 participants aged 20 to 69, the researchers found that there was indeed a significant difference. The participants were shown a visual diagram explaining how gene-editing works and then asked how they felt about it. The survey results showed that they were more likely to be worried about the use of gene-editing techniques on livestock than on plants.

But in a twist to the study design, the researchers split the participants into two groups. In the first, the explainer diagram included cartoon pictures of pigs, and in the second, the diagram included cartoon pictures of tomatoes.

The group that had been shown pictures of cartoon pigs were subsequently less likely to raise concerns about gene-editing of livestock than the group that had been shown pictures of cartoon tomatoes. The researchers believe that this may be because the pictures of the pigs "primed" the survey participants to be open to livestock gene-editing. "In contrast, the group shown the gene-editing of cartoon tomatoes had in effect been asked to infer how they would feel if the same thing was done on pigs" says Naoko Kato-Nitta, the lead author of the paper and a specialist in risk communication at ROIS and the Institute of Statistical Mathematics in Tokyo. "There was a higher emotional hurdle to be overcome in the second group."?"This means that public attitudes towards food can change as a result of just one small change to how information is provided," she adds. "And so experts really need to pay careful attention to the impact of how they contextualize their discussions of gene-editing."

The survey participants were also asked a series of questions assessing their level of scientific literacy. The researchers found that those with higher levels of scientific literacy were more supportive of using gene-editing to deliver improvements in vegetables, and more supportive of using gene-editing to make livestock more resistant to disease. Those with higher levels of scientific literacy thus may be more open to medical applications of biotechnology than agri-food applications.

In the 1990s, strong public opposition to genetically modified crops led to the Japanese government's introduction of strict regulations on such techniques, as well as the labeling of GM food items. Currently there is no commercial cultivation of GM crops in the country. And so the researchers now want to perform the study again in other countries in order to see if the plant-animal consumer distinction is culturally specific to Japan.

###

About the Joint Support-Center for Data Science Research (ROIS-DS)

The Joint Support-Center for Data Science Research (ROIS-DS) is a part of Japan's Research Organization of Information and Systems (ROIS). Established in 2016, ROIS-DS is a joint research center for the advancement of interdisciplinary data science. The center's mission is to support wide range of researchers and students to conduct research in data-sciences in the hope of solving scientific and social problems. The center aims to cultivate and strengthen collaboration and cooperation among universities and other institutions by promoting data sharing and providing data analysis support across disciplines, as well as helping human resource development related to data science.

About the Institute of Statistical Mathematics

The Institute of Statistical Mathematics (ISM) is part of Japan's Research Organization of Information and Systems (ROIS). With more than 75 years of history, the institute is an internationally renowned facility for research on statistical mathematics including survey research and the Japanese national character survey. ISM comprises three different departments including the Department of Statistical Modeling, the Department of Statistical Data Science, and the Department of Statistical Inference and Mathematics, as well as several key data and research centers. Through the efforts of various research departments and centers, ISM aims to continuously facilitate cutting edge research collaboration with universities, research institutions, and industries both in Japan and other countries.

 

Sharing and enjoying meals with loved ones reduces obesity and improves the health of adolescents

The benefits of the Mediterranean diet come from both the food we eat and how we eat it

UNIVERSITAT OBERTA DE CATALUNYA (UOC)

Research News

 

IMAGE: UOC RESEARCHER, ANNA BACH-FAIG, EXPERT IN NUTRITION view more 

CREDIT: UOC

Eating together as a family, maintaining the Mediterranean diet's traditional customs of conviviality, influences the eating habits of adolescents and prevents eating behaviour disorders, according to a new study prepared by scientists from the Universitat Oberta de Catalunya (UOC) and the Universitat Autònoma de Barcelona (UAB) and published in the open access International Journal of Environmental Research and Public Health.

"At a time when lockdown due to the pandemic has revived family meals, this study indicates one of the possible positive aspects of the situation that we have had to confront", explains the study's researcher Anna Bach-Faig from the Foodlab group, and a member of the Faculty of Health Sciences.

The research establishes that family meal routines, such as sharing food, sitting around a table without digital devices or having a pleasant conversation, are beneficial aspects for adolescents and contribute to their health. In line with other studies it notes that this conviviality, which favours conversation and slower eating, helps adolescents to recognize the feeling of fullness during meals and, indirectly, prevents obesity.

The study, conducted by means of in-depth interviews of families in Catalonia with adolescents from 12 to 16 years old, analyses one of the least studied aspects of the Mediterranean diet: socialization at mealtimes and how the way in which we eat also affects our health.

"A healthy diet is not just what we eat but also how we eat it", explains Bach-Faig. "The Mediterranean diet is much more than a list of foods. It is a cultural model which includes how these foods are selected, produced, processed and consumed."

The importance of conversation

To determine the degree of conviviality in the families studied, the researchers analysed the frequency and duration of family meals, the place where they took place, the use of digital devices, the preparation of the food and the type of communication established in these gatherings.

According to the study, the majority of families only ate the evening meal together and their habits varied depending on whether they ate alone or with their loved ones. The research ascertained that family meals were a place for communication and socialization, and that when families devoted less time to them, did not sit at the table, were distracted by digital devices or did not engage in pleasant conversation during these gatherings, they also followed the Mediterranean diet to a lesser extent.

For the majority of parents, family meals were especially important when they had adolescent children, since they favour conversation and closer family bonds. "It is easier when children are small, but in adolescence there is a disconnect between you and them and, thanks to these conversations, you can gain a little insight into their world", explained one of the mothers interviewed.

Moreover, the majority considered that, through these family gatherings, parents become role models and help to establish healthy patterns for their children. This impression is consistent with the results of other studies in which it is demonstrated that eating together as a family is related to a healthier diet, with more fruit and vegetables, and less sugary drinks.

The Western diet

For nutrition expert Bach-Faig, it is essential to preserve eating traditions in order to maintain the benefits of the Mediterranean diet and promote the health of the younger generations. However, for several decades now, the Mediterranean diet has been losing influence in the face of the so-called "Western diet", characterized by the predominance of processed foods and eating quickly, often in front of the television.

The study stresses that it is crucial to consider these aspects in order to promote a healthy diet among adolescents and to design public health campaigns. One example was the Implica't campaign, carried out in Catalonia with the participation of researchers from this study. "Just as we recommend 5 fruit and veg a day", explains Bach-Fair, "we could also propose at least one family meal a day".

###

This UOC research contributes to Sustainable Development Goal (SDG) 3 (good health and well-being).

The study was supported by a Research Grant from the Spanish Ministry of Science, Innovation and Universities (RTI2018-099293-B-I00).

Reference article:

de la Torre-Moral, A.; Fàbregues, S.; Bach-Faig, A.; Fornieles-Deu, A.; Medina, F.X.; Aguilar-Martínez, A.; Sánchez-Carracedo, D. Family Meals, Conviviality, and the Mediterranean Diet among Families with Adolescents. Int. J. Environ. Res. Public Health 2021, 18, 2499. https://doi.org/10.3390/ijerph18052499

UOC R&I

The UOC's research and innovation (R&I) is helping overcome pressing challenges faced by global societies in the 21st century, by studying interactions between technology and human & social sciences with a specific focus on the network society, e-learning and e-health. Over 500 researchers and 51 research groups work among the University's seven faculties and two research centres: the Internet Interdisciplinary Institute (IN3) and the eHealth Center (eHC).

The United Nations' 2030 Agenda for Sustainable Development and open knowledge serve as strategic pillars for the UOC's teaching, research and innovation. More information:research.uoc.edu. #UOC25years

 

Adolescents born preterm have similar self-esteem/wellbeing levels to those born full-term

New research led by the universities of Kent and Warwick has found that, contrary to previous beliefs, adolescents born preterm have the same levels of self-esteem and overall wellbeing as those born full-term

UNIVERSITY OF KENT

Research News

 

New research led by the universities of Kent and Warwick has found that, contrary to previous beliefs, adolescents born preterm have the same levels of self-esteem and overall wellbeing as those born full-term.

Preterm birth, defined as birth before 37 weeks of gestation, has been previously found to be associated with an increased risk for lower academic achievement, higher mental health problems and increased difficulties in social relationships compared to those born full-term. This new study, co-led by Dr Ayten Bilgin (Kent) alongside colleagues from Warwick, demonstrates that in contrast, preterm birth does not affect the development of subjective wellbeing and self-esteem, which are personal evaluations and thus different from school grades or psychiatric diagnoses.

The research paper, published by the Journal of Developmental & Behavioral Pediatrics, reveals how adolescents born very preterm (28 to 32 weeks) or moderate-to-late preterm (32 to 37 weeks) are no different from those born full-term regarding general subjective wellbeing, and family, school and physical appearance related wellbeing, and global self-esteem.

However, the study found that adolescents born very preterm perceive their peer relationships as poorer than those born full-term. This would indicate that interventions to enhance wellbeing in very preterm adolescents may be focused around improving peer relationships in childhood and adolescence.

Dr Bilgin said: 'It is very encouraging to find that preterm born adolescents show the same levels of self-esteem and wellbeing as full-term born adolescents, despite the association between preterm birth and increased mental health problems. We hope our findings will impact the focus of future studies.'

Dieter Wolke, Professor of Developmental Psychology and Individual Differences at the University of Warwick's Department of Psychology, added: 'It is concerning that those born preterm perceive themselves to have poorer peer relationships. Together with our previous evidence that preterm children may be more often the subject of bullying, supporting friendships and peer relations in school and leisure activities should be a priority.'

###

For their study, the team utilised data from: The Avon Longitudinal Study of Parents and Children (ALSPAC; United Kingdom); the Millennium Cohort Study (MCS; United Kingdom); the Basel Study of Preterm Children (BSPC; Switzerland); and the Bavarian Longitudinal Study (BLS; Germany). Using questionnaires, a total of 986 moderate-to-late preterm, 412 very preterm and 12,719 full-term born adolescents reported on wellbeing and 927 moderate-to-late preterm, 175 very preterm and 13,312 full-term born adolescents reported on self-esteem. The age of the participants ranged from 12-17 years.

'Subjective Well-Being and Self-Esteem in Preterm Born Adolescents: An Individual Participant Data Meta-Analysis' is published by the Journal of Developmental & Behavioral Pediatrics. (Dr Ayten Bilgin, Kent; Dr Asteria Brylka, Warwick; Professor Dieter Wolke, Warwick; Dr Hayley Trower; Warwick; Nicole Baumann, Warwick; Professor Sakari Lemola, University of Bielefeld). DOI: 10.1097/DBP.0000000000000947

 

Maternal stress in conception linked to higher chance of female foetus

Women who experience more stress around the time of conception are twice as likely to give birth to a girl

UNIVERSITY OF GRANADA

Research News

 

IMAGE: THE UGR RESEARCH TEAM THAT CONDUCTED THIS STUDY view more 

CREDIT: UNIVERSITY OF GRANADA

A total of 108 women participated in the research from the first weeks of pregnancy to delivery, having recorded their stress levels before, during, and after conception (via the concentration of cortisol in hair) and performed different psychological tests

A study carried out by scientists from the University of Granada (UGR) has revealed that women who experience stress both before becoming pregnant and during conception are almost twice as likely to have a girl as a boy.

Researchers from the Mind, Brain and Behaviour Research Centre (CIMCYC), the Department of Pharmacology (Faculty of Pharmacy), and the Faculty of Psychology have analysed the levels of cortisol (a steroid hormone that is released in response to stress) in the hair of pregnant women in the period spanning from before conception to week 9 of pregnancy, to determine whether there was any link with the sex of the baby.

A total of 108 women were monitored from the first weeks of pregnancy through to delivery, to record their stress levels before, during, and after conception via the concentration of cortisol in their hair and various psychological tests. The measurement of cortisol in hair samples taken approximately in week 8-10 of pregnancy showed the concentration of cortisol in the pregnant woman for the previous three months (one month per centimetre of hair growth), meaning that it covered the period preceding and after conception. Subsequently, the UGR scientists recorded different variables relating to the birth and the sex of the baby.

María Isabel Peralta Ramírez, the main author of this work and researcher at the UGR's Department of Personality, Evaluation and Psychological Treatment explains: "The results we found were surprising, as they showed that the women who had given birth to girls presented higher concentrations of hair cortisol in the weeks before, during, and after the point of conception than those who had boys." In fact, these cortisol concentrations in the hair of mothers who subsequently had girls were almost double those who had boys.

Consequences of stress

There is ample scientific evidence demonstrating the impact of stress on the mother in the processes of pregnancy, birth, and even infant neurodevelopment. "Specifically, our research group has shown in numerous publications how psychological stress in the mother generates a greater number of psychopathological symptoms during pregnancy, postpartum depression, a greater likelihood of assisted delivery, an increase in the time taken for lactation to commence (lactogenesis), or inferior neurodevelopment of the baby six months after birth," says Peralta.

All of the existing research tells us about the effect of stress when pregnancy has already occurred. However, few studies have shown the link between stress and the mother-to-be before or during the conception of the baby, the present study being a rare exception. Its findings were recently published in the prestigious Journal of Developmental Origins of Health and Disease.

One possible explanation for the results would be that the activation of the "stress system"--the hypothalamus-pituitary-adrenal gland system--which involves an increase in cortisol secretion, modifies the concentrations of sex hormones at the time of conception. However, the mechanisms underlying this modification are not clear, because, on the one hand, there is evidence that testosterone could influence the determination of the baby's sex, since the higher the levels of prenatal stress, the higher the levels of female testosterone.

On the other hand, there is scientific evidence that sperm carrying the X chromosome (which determines that the baby will be female) perform better at passing through the cervical mucus in circumstances of adversity. Therefore, due to the hormonal changes associated with stress in the mother, these sperm are more likely to be successful in reaching the egg than sperm carrying the Y chromosome (which determines that the baby will be male).

"There are other possible hypotheses that attempt to explain this phenomenon. Among the strongest theories is the idea that there are more terminations of male foetuses on medical grounds during the first weeks of gestation in situations of severe maternal stress. That said, in light of the design of these studies, it is recommended that the results are corroborated in greater depth," observes Peralta.

The effect of stress on the foetus

What does appear to be clear-- and this has been shown in several studies--is that foetuses are vulnerable to the effect of stress, since it plays a key role in their development. An example of this is the proven fact that male (XY) foetuses mature more slowly than female (XX) foetuses; they tend to be associated with more complications in pregnancy and premature delivery; and, at birth, they are more likely to have shorter telomeres. This renders XY foetuses more vulnerable to adverse prenatal environments, suggesting that women who experience high levels of stress around the time of conception may be less likely to give birth to a boy.

###

This study was conducted by members of the research group Neuropsychology and Psychoneuroimmunology Applied to Children, Adults and the Elderly. It operates under the auspices of the Framework for R&D Projects granted by the Spanish Ministry of Science, Innovation and Universities (ABORSTRESS AND CHILDSTRESS).

 

Tiny brains grown in 3D-printed bioreactor

Small device contains wells to let small bits of tissue grow, develop, and be studied in real time

AMERICAN INSTITUTE OF PHYSICS

Research News

 

IMAGE: A 3D-PRINTED MICROFLUIDIC BIOREACTOR FOR ORGAN-ON-CHIP CELL CULTURE view more 

CREDIT: IKRAM KHAN

WASHINGTON, April 6, 2021 -- Scientists from MIT and the Indian Institute of Technology Madras have grown small amounts of self-organizing brain tissue, known as organoids, in a tiny 3D-printed system that allows observation while they grow and develop. The work is reported in Biomicrofluidics, by AIP Publishing.

Current technology for real-time observation of growing organoids involves the use of commercial culture dishes with many wells in a glass-bottomed plate placed under a microscope. The plates are costly and only compatible with specific microscopes. They do not allow for the flow or replenishment of a nutrient medium to the growing tissue.

Recent advances have used a technique known as microfluidics, where a nutrient medium is delivered through small tubes connected to a tiny platform or chip. These microfluidic devices are, however, expensive and challenging to manufacture.

The current advance uses 3D printing to create a reusable and easily adjustable platform that costs only about $5 per unit to fabricate. The design includes imaging wells for the growing organoids and microfluidic channels to provide a nutrient medium and preheating that supports tissue growth.

A biocompatible type of resin used in dental surgery was used for the 3D-printed device. The printed chip was cured by exposing it to UV light, then sterilized before live cells were placed in the wells. After sealing the top of the wells with a glass slide, the nutrient medium and drugs for use in the study were added through small inlet ports.

"Our design costs are significantly lower than traditional petri dish- or spin-bioreactor-based organoid culture products," said author Ikram Khan. "In addition, the chip can be washed with distilled water, dried, and autoclaved and is, therefore, reusable."

The investigators tested their device with organoids derived from human cells. They observed the growing brain organoids with a microscope and were able to successfully follow their growth and development for seven days. The small bit of brain tissue developed a cavity or ventricle surrounded by a self-organizing structure that resembles a developing neocortex.

The percentage of cells in the core of the organoid that died during this one-week period was smaller in the 3D-printed device than in regular culture conditions. The investigators believe that their cell design protects the tiny growing brain.

Khan said, "One advantage offered by our microfluidic device is that it allows constant perfusion of the culture chamber, which more closely mimics a physiological tissue perfusion than conventional culture, and thus reduces cell death at the organoid core."

The investigators hope to increase the capacity of their device by scaling up the number of available wells. Other improvements will allow for additional instruments to be integrated into the design.

###

The article "A low-cost 3D printed microfluidic bioreactor and imaging chamber for live-organoid imaging" is authored by Ikram Khan, Anil Prabhakar, Chloe Delepine, Hayley Tsang, Vincent Pham, and Mriganka Sur. The article will appear in Biomicrofluidics on April 6, 2021 (DOI: 10.1063/5.0041027). After that date, it can be accessed at https://aip.scitation.org/doi/10.1063/5.0041027.

ABOUT THE JOURNAL

Biomicrofluidics rapidly disseminates research in fundamental physicochemical mechanisms associated with microfluidic and nanofluidic phenomena. The journal also publishes research in unique microfluidic and nanofluidic techniques for diagnostic, medical, biological, pharmaceutical, environmental, and chemical applications. See https://aip.scitation.org/journal/bmf.

 

Brain cells decide on their own when to release pleasure hormone

NYU LANGONE HEALTH / NYU SCHOOL OF MEDICINE

Research News

 

In addition to smoothing out wrinkles, researchers have found that the drug Botox can reveal the inner workings of the brain. A new study used it to show that feedback from individual nerve cells controls the release of dopamine, a chemical messenger involved in motivation, memory, and movement.

Such "self-regulation," the researchers say, stands in contrast to the widely held view that the release of dopamine -- known as the "feel good" hormone -- by any cell relied on messages from nearby cells to recognize that it is releasing too much of the hormone.

Led by researchers at NYU Grossman School of Medicine, the new study showed that dopamine-releasing brain cells respond to their own signals to regulate the hormone's output. Because the death of dopamine-releasing brain cells is a key factor in Parkinson's disease, the new findings provide insight into why these cells die in the movement disorder, the researchers say.

"Our findings provide the first evidence that dopamine neurons regulate themselves in the brain," says study lead author Takuya Hikima, PhD. "Now that we better understand how these cells behave when they are healthy, we can start to unravel why they break down in neurodegenerative disorders like Parkinson's disease," adds Hikima, an instructor in the Department of Neurosurgery at NYU Langone Health.

Hikima says their study was prompted by what the research team saw as flaws in the older way of thinking about how dopamine works. First, for one cell to control its neighbor with dopamine, a large number of synapses, or junctions where two cells meet and exchange messages, would be required. Yet researchers say there were not enough synapses to account for this. Second, many types of hormone-producing cells in the body use a streamlined system that self-regulates further release, so it seemed odd that dopamine neurons would use a more roundabout process.

For the study, publishing April 6 in the journal Cell Reports, the research team collected dopamine neurons from dozens of mice. They injected some of the brain cells with Botox, a toxin that blocks nerve cells from sending chemical messages to neurons and other cells. The chemical's nerve-blocking action accounts for its ability to relax muscles in migraine and wrinkle treatments.

By injecting Botox into single neurons, says Hikima, the researchers hoped to show whether any signal to continue or stop dopamine release could only come from outside the "paralyzed" cell. If the neurons were in fact controlled by neighboring dopamine cells, then dopamine release would remain unaffected because the treated cells would still receive dopamine signals from the untreated cells nearby.

Instead, the findings revealed a 75 percent drop in dopamine outflow, suggesting that dopamine neurons largely rely on their own discharge to determine release rate of the hormone, according to the investigators.

"Since our Botox technique helped us solve the problem of how dopamine neurons regulate their communication, it should also enable us to uncover how other nerve cells interact with each other in the mammalian brain," says study senior author Margaret Rice, PhD.

The research team next plans to explore other areas of dopamine neuron activity that remain poorly understood, such as the dependence of dopamine release on calcium from outside the brain cells, says Rice, a professor in the Departments of Neurosurgery and Neuroscience and Physiology at NYU Langone. The investigators also intend to examine how self-regulation of dopamine might contribute to cell death in Parkinson's disease.

###

Funding for the study was provided by National Institute of Health grants R01 DA038616 and R01AI093504 and by the Marlene and Paolo Fresco Institute for Parkinson's Disease and Movement Disorders.

In addition to Hikima and Rice, other NYU Langone researchers include Christian Lee, PhD; Paul Witkovsky, PhD; Julia Chesler, PhD; and Konstantin Ichtchenko, PhD.