SOMNAMBULISM

'Fight or flight' discovery in sleepwalkers paves way to new understanding of phenomenon

New research published in the open access journal Frontiers investigating the biological mysteries of sleepwalking found the levels of 'fight or flight' response in those who wander at night is surprisingly lower than those who sleep soundly

FRONTIERS

Research News

 

Somnambulism - otherwise known as sleepwalking - is a phenomenon which has fascinated the public and neurologists for decades, but a lot of what causes it remains a mystery.

Affecting up to 4% of adults, sleepwalking is a non-rapid-eye movement (NREM) sleep parasomnia that not only gives someone a poor night's sleep, but also puts them at serious risk of injury and, in some cases, lead to unintended violence against others.

The following day can also prove challenging as the sleepwalker will feel unrested and a strong desire to fall asleep (somnolence).

Unfortunately for those predisposed to sleepwalking episodes, prolonged sleep deprivation increases both their frequency and complexity, making it harder for them to achieve the deep sleep the body needs to function healthily.

Now, in a paper published to Frontiers in Neurology, researchers at the University of Montréal and Montréal Sacred Heart Hospital, Canada aimed to further investigate the hypothesis that sleepwalking is a disorder of arousal and poorly regulated deep sleep (slow-wave sleep).

More specifically, they examined how the autonomic nervous system - measured via the heart rate - influences deep sleep in sleepwalkers.

Challenges of a sleepwalking study

14 adult sleepwalkers were recruited for the study as well as 14 sex- and age-matched normal controls. They were evaluated using video-polysomnography for one night and during recovery sleep following 25 hours of sleep deprivation.

According to corresponding authors Prof Antonio Zadra and Dr Andrée-Ann Baril of the University of Montréal, it can be a challenge to put together a study investigating the mysterious inner workings of sleepwalking.

"One challenge in studying large cohorts of sleepwalkers is the relatively low prevalence of the disorder in the adult population," they said.

"Fortunately, the Center for Advanced Research in Sleep Medicine, where this research was conducted, is a one-of-a-kind clinical and research facility in Canada affiliated with one of the country's largest and highly specialized sleep disorders clinics that assesses over 1,000 patients a year. As a general rule, however, adult sleepwalkers are readily willing to take part in research studies aiming to better understand the underlying causes and possible treatments of the sleep disorder."

Wakefulness and deep sleep at the same time

The autonomic nervous system regulates the body's physiological functions and is composed of the sympathetic branch, which underlies the 'fight or flight' response, and the parasympathetic branch, which underlies the 'rest and digest' response. Zadra, Baril, and the rest of their team found that sleepwalkers show an elevated rest-and-digest response and a lower fight-or-flight response during deep sleep.

"While the causes of sleepwalking remain unclear, we know that while asleep, sleepwalkers can experience an abnormal interplay between processes linked to arousal and to deep sleep, even outside of their episodes," Zadra and Baril said.

"In other words, sleepwalkers can present evidence of both wakefulness and deep sleep at the same time; a state out of which episodes of sleepwalking can arise. Our findings indicate that when compared to healthy adults, sleepwalkers' autonomic nervous system favors their parasympathetic activity, or rest-and-digest response, during sleep. This paves a new and broader way to understand the biological processes implicated in sleepwalking."

Surprising discovery

The results were "surprising", they added, as it had been assumed that the deep sleep of sleepwalkers would show an elevated fight-or-flight response that would predispose them to higher risks of experiencing sleepwalking episodes.

One limitation of the study is that measuring the influence of the sympathetic and parasympathetic branches on a person's heartbeat is an indirect approach and can be confounded by other factors.

"While our results indicate the presence of an altered autonomic nervous system during sleepwalkers' deep sleep, whether and how this atypical activity is involved in the occurrence of actual sleepwalking episodes remains to be determined," Zadra and Baril said.

"Since several pharmaceutical agents can be used to modulate autonomic effects, such treatment venues could be explored if our results are replicated and expanded upon."

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Mixed cultures for a greater yield

ETH ZURICH

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IMAGE: A TWO-SPECIES MIXTURE WITH TWO ALTERNATING ROWS OF OATS AND BLUE LUPIN IN SPAIN. view more 

CREDIT: CHRISTIAN SCHOEB, CROP DIVERSITY EXPERIMENT / ETH ZURICH

Monocultures dominate arable land today, with vast areas given over to single elite varieties that promise a high yield. But planting arable land with just one type of crop has its disadvantages: these areas are easy game for fungal and insect pests, posing a threat to crops. To keep pests at bay, farmers are having to use resistant varieties and various pesticides.

Mixed cultures present a potential alternative to monocultures. Rather than having large expanses of land planted with just one species or variety, several species or varieties are sown alongside each other. However, as little research has been done into this method, especially from an agricultural perspective, mixed cultures are rare in arable farming.

A team led by ETH Zurich Professor Christian Schöb has now revealed that mixed cultures actually produce a much higher yield than monocultures in arable farming. Their study was recently published in the journal Nature Plants.

Applying an ecological principle

Mixed cultures draw on the ecological principle that ecosystems are able to perform their functions more effectively where there is greater biodiversity. These functions include regulating water balance, maintaining soil fertility and increasing plant productivity.

This also goes for agricultural ecosystems: "Research into agriculturally used meadows has shown that areas with a larger mix of plants are more productive than those with just one or a few species," Schöb says.

Until now, barely any comparable studies had focused on arable farming. That is why, together with his colleagues, Schöb set out to investigate whether this basic ecological mechanism would also have a bearing on arable land, specifically with regard to yield.

The researchers created two test gardens: one in Switzerland, on the University of Zurich's Irchel campus, and the other in the Spanish province of Extremadura. The latter has a much drier and warmer climate than Zurich, allowing the researchers to examine how the crops grow under potential future climate conditions.

Greater yield from mixing just two crops

In their experiment, the researchers tested mixtures of two or four different crops chosen from eight selected species comprising wheat, oat, quinoa, lentil, lupin, flax and false flax (an oilseed similar to rapeseed) as well as coriander. Only the seeds of the different species were used. The plants were sown 12 centimetres apart in alternating, parallel rows.

The researchers compared the seed mass from the mixed-culture crops with those from monocultures. They also measured plants' biomass based on their growth above ground.

The result speaks for itself: compared to monoculture farming, even a mixture of two species increased yield by 3 percent in Spain and 21 percent in Switzerland. Where the researchers had sown four species alongside each other, the yield increase was as high as 13 and 44 percent in Spain and Switzerland respectively.

The researchers explained that this additional yield primarily comes down to the biodiversity effect: a greater variety of plants results in a better use of available resources and more effective, natural pest control - the experiments were conducted without pesticides.

Plants put a lot of energy into leaves and stems

The researchers also noted, however, that the plants in mixed cultures developed more leaves or stems than in monocultures. In other words, the plants invested more energy and matter in producing vegetative biomass and proportionally less into producing seeds. Schöb explained that the plants were having to make a compromise: the more effort they put into vegetative biomass, the less they have for seeds. "Despite this, the plants still produced more seeds on balance than in a monoculture," says the agricultural researcher.

He attributed the fact that the plants invested more energy in creating vegetative biomass to the varieties used in the experiments. "The seeds are bred specifically for monocultures. This means the plants are designed to perform best when they grow among other plants of the same variety."

Schöb deems it likely that the potential for extra yield is even greater with seeds suited to mixed cultures.

Over time, people have changed most crops to produce larger fruit and higher yield under monoculture conditions. The tomatoes grown today are gigantic compared with their wild counterparts, which have fruit the size of blueberries. In order to get the best yield possible from plants grown in mixed cultures, current breeding methods - targeting cultivation in monocultures - have to be adjusted slightly.

Sowing the right seeds

As things stand, no seeds are produced or marketed specifically for use in mixed cultures. The researchers are therefore busy harvesting and testing seeds from their own experiments. "We want to repeat our experiments using these self-produced seeds so we can test whether selection in a mixed culture literally does bear fruit," Schöb says.

A change in agricultural practice is, however, required if mixed cultures are to gain ground. Among other things, machines need to be able to harvest different crops at the same time and also separate the different harvest products. "These machines exist, but they are few and far between, not to mention expensive. There is simply too little demand for them at present," Schöb says. Together with optimised seeds and the right machines, mixed cultures will present farmers with a real opportunity for the future.

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Chen JG, Engbersen N, Stefan L, Schmid B, Sun H, Schöb C: Diversity increases yield but reduces reproductive effort in crop mixtures, Nature Plants, 2021, published online 24th June. Doi: 10.1038/s41477-021-00948-4

 

The molecular characteristics of the dissolved organic matter pool in a eutrophic coastal bay

SCIENCE CHINA PRESS

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IMAGE: CONCEPTUAL DIAGRAM OF THE DISSOLVED ORGANIC MATTER POOL. view more 

CREDIT: ©SCIENCE CHINA PRESS

Coastal bays are momentous transition zones connecting terrestrial and marine ecosystems. Xiangshan Bay is a typically eutrophic and semi-enclosed bay in the East China Sea. A recent study took Xiangshan Bay as an example, revealing the sources and transformation of dissolved organic matter (DOM) in this eutrophic bay.

Dissolved organic matter (DOM), consisting of a vast of complex compounds, has received much attention due to its significant contribution to the largest reduced organic carbon pool in the ocean, which is sizable to the atmosphere CO2 reservoir.

Coastal bays are known as semi-enclosed signature and long water retention time compared with river-dominated estuaries. In fact, they serve as links between rivers and oceans to transport organic carbon. However, they were universally exposed to high fluxes of nutrients from intensive anthropogenic activities such as sewage discharge and aquaculture industry with the rapid urbanization due to their locations near human settlements. Large nutrient fluxes could lead to coastal eutrophication with harmful algal blooms, which have been observed in a couple of coastal bays, such as Jiaozhou Bay and Xiangshan Bay in China. The high primary productivity, as well as subsequent biogeochemical processes, induced from eutrophication might impact the chemical composition and flux of organic matter transported to the open ocean. As such, coastal bays are supposed to be not only "conduits" where organic matter is transported to open oceans, but also "reactors" where organic matter is processed or transformed.

Describing Xiangshan Bay as "one of the most valuable testing places around the world", researchers from Zhejiang University pointed out the immense value of investigating the compositions of DOM pool in Xiangshan Bay: "It is recognized as a typically long, narrow coastal bay, with long water retention time, which would facilitate the biogeochemical processing of organic matter. Furthermore, it has been the largest aquaculture base in Zhejiang province, causing severe eutrophication with harmful algae blooms."

Biogeochemical researches conducted in other coastal bays, since the emergence of the spectroscopic, have revealed "Physical mixing, photo-oxidation, and tidal effects might affect the behaviors of DOM in such systems" according to Yu Pang and Chen Zhao, graduate students at the School of Earth Sciences, Zhejiang University, in the Chinese city of Hangzhou.

In an article coauthored with Yuping Zhou, Yanzhen Zhang, Wei Huang, Yuntao Wang, scholars at Zhejiang University and Second Institute of Oceanography, Ministry of Natural Resources, combined multiple approaches, these researchers stated: "Terrestrial, marine, and anthropogenic inputs collectively contribute to the whole DOM pool. The conclusion was confirmed by both optical and molecular approaches. One protein-like component and two humic-like components were identified by spectroscopic techniques and molecular groups associated with different sources were also determined."

These authors revealed in the study, which was published in the journal of Science China: Earth Sciences, that terrestrial signals gradually decrease from the upper to lower bay with increasing salinity due to seawater dilution effect while protein-like fluorescent component may derive from multiple sources because a similar linear relationship is lacking.

Research aimed at solving this issue faced an array of obstacles: The isolation, extraction, and chemical characterization of DOM are prerequisites to understand its cycling in aquatic systems. However, except for a few sugars, amino acids, and lignin phenols, compositions of most DOM are still largely uncertain because of its complexity, heterogeneity, and low concentration in natural environments. Understanding the chemical composition and sources is a prerequisite to determine the DOM cycling in aquatic environments.

"Traditional techniques could only be reflective of the bulk chemistry of the DOM while our knowledge of the molecular-level composition of DOM is still lacking. To date, limited studies have combined optical and molecular approaches to systematically investigate the DOM composition in coastal bays."

To solve this problem, these researchers applied Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICRMS), a state-of-the-art tool offering a possibility to precisely obtain molecular-level information of DOM. In the recent years, scientists have established a variety of indices to depict DOM based on the data obtained from FT-ICRMS.

The researchers found that the physical mixing resulting from seawater dilution effect still occurs in Xiangshan Bay during summer, which has been widely found in river-dominated estuaries around the world. Also, the detection of anthropogenic-associated S-containing compounds confirms the inputs from human activities. Anthropogenic inputs may be a significant source of DOM in coastal bays when comparing Xiangshan Bay with other Chinese bays.

The data obtained from FT-ICRMS suggested that photo-induced degradation play a critical role in altering DOM compositions, considering molecular compositions imprint pronounced labile signatures compared with other aquatic environments.

"To the best of our knowledge", wrote the seven researchers, "this work will also shed lights on future studies focusing on the estuarine carbon cycling."

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See the article: Zhao C, Zhou Y, Pang Y, Zhang Y, Huang W, Wang Y, He D. 2021. The optical and molecular signatures of DOM under the eutrophication status in a shallow, semi-enclosed coastal bay in southeast China. Science China Earth Sciences, 64, https://doi.org/10.1007/s11430-020-9728-4

 

A hidden driver of food insecurity and environmental crisis that we cannot ignore

SCIENCE CHINA PRESS

Research News

IMAGE: CHANGES IN CROPLAND PATTERN, AREA AND QUALITY ACROSS CHINA. (A) CROPLAND CHANGE ACROSS CHINA DURING 1990-2000. (B) CROPLAND CHANGE ACROSS CHINA DURING 2000-2015. (C) CROPLAND QUALITY LEVELS ACROSS CHINA. (D)... view more 

CREDIT: ©SCIENCE CHINA PRESS

The cultivated planet is withstanding record-breaking pressure to ensure food security. To meet the rising demand of food, energy, and fiber, a 70%-100% increase in crop commodities will be needed globally by 2050. However, rapid urbanization and industrialization have caused dramatic loss of high-quality cropland and hence threatened food security. To stabilize cropland area, cropland expansion to marginal lands has become a widespread phenomenon worldwide. This study developed a systems framework to represent the trade-off among crop yield, production, and environmental cost, according to the competitive relationship of production, settlement, and ecological space and the link of "land - food - environment - policy". Using China as a case study, the authors validated the systems framework by assessing the associated food benefits and environmental costs from large-scale cropland redistribution driven by economic development and policy implementation.

The environmental impacts of cropland redistribution in China were invesgated. Due to urbanization-induced loss of high-quality croplands in south China (~8.5 t ha-1), croplands were expanded to marginal lands in northeast (~4.5 t ha-1) and northwest China (~2.9 t ha-1) during 1990-2015 to pursue food security. However, the reclamation in these low-yield and ecologically vulnerable zones considerably undermined local environmental sustainability, e.g., increasing wind erosion (+3.47%), irrigation water consumption (+34.42%), fertilizer use (+20.02%), and decreasing natural habitats (-3.11%). Forecasts show that further reclamation in marginal lands per current policies would exacerbate environmental costs by 2050. The future cropland security risk will be remarkably intensified due to the conflict between food production and environmental sustainability. Kuang et al.'s results suggest that globally emerging reclamation of marginal lands should be restricted and crop yield boost should be encouraged for both food security and environmental benefits.

The findings in this paper reveal that, under the influence of national macro policies, the competition of urban, agriculture and ecology systems driven by "the supplement of marginal lands and loss of high-quality croplands in the future" lead to the trade-off relationship between food production and environmental sustainability. The paper also confirms that the global or specific regional marginal lands beyond a certain threshold will not increase grain production, but will cause environmental unsustainability.

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See the article:

Cropland redistribution to marginal lands undermines environmental sustainability. Wenhui Kuang et al. National Science Review, https://doi.org/10.1093/nsr/nwab091

https://doi.org/10.1093/nsr/nwab091  

CAPTION

Impact of cropland redistribution on grain production in China during 1990 to 2015. (A) spatial change in grain production, (B) Change in total grain production. Cropland redistribution contributed to a 4.5% reduction in grain production (equivalent to feeding 57×106 people), although the total cropland area remained steady. On average, one ton of grain production needs only 0.10 ha, 0.19 ha, or 0.18 ha of croplands in SE, SW, or N China, which have relatively high yield (on average 8.53 t ha-1 yr-1) and two or three crop rotations. Whereas 0.35 ha in NW China or 0.22 ha in NE China is needed to produce the same amount of grain, which has relatively low yields (on average 2.89 t ha-1 yr-1 and 4.50 t ha-1 yr-1, respectively) and one crop rotation. NE and NW China are two hot regions for increasing grain production and contribute a total grain of 2011 ×104 t yr-1 and 1042 ×104 t yr-1, respectively.

CREDIT

©Science China Press

CAPTION

Environmental effects of national cropland redistribution on irrigation water use and soil erosion by wind. (A) Spatial distribution of water demand deficit. (B) Cropland area and proportion of different water demand deficit levels, and the irrigation water use increase resulting from cropland gain in each zone. (C) Spatial distribution of average wind erosion modules. (D) Effect of cropland gain on soil erosion by wind in each zone. (E) Spatial distribution of average fertilizer use per crop yield. (F) The increase of fertilizer use resulting from cropland gain in each zone. Cropland redistribution to NE and NW China since 2000 has resulted in serious environmental costs and aggravated the local ecological vulnerability. The newly cultivated croplands in NE and NW China increased wind erosion (+3.47%), irrigation water consumption (+34.42%), fertilizer use (+20.02%), and decreased natural habitats (-3.11%). The croplands converted from grasslands or oases in NW China were primarily located in arid and semi-arid areas with mean annual precipitation less than 200 mm yr-1. The precipitation can meet only 18.7% to ~54.0% of crop water demand in NW China, resulting in an increase in irrigation water use by 278.65×108 m3 yr-1. Since more than half of the croplands in NW China (55.4%) were located in water demand deficit areas after redistribution, extracting groundwater for irrigation caused continuous groundwater depletion. The environmental costs in water use and black soil degradation were also high in NE China, due to the local precipitation can only meet about 60% of crop water demand.

CREDIT

©Science China Press

Cyclone study improves climate projections

A new study quantifies how cyclones contribute to global climate systems

UNIVERSITY OF TOKYO

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IMAGE: THE NORTHERN WESTERLY JET STREAM, INDICATED BY THE THICK RED ARROW, IS ESPECIALLY IMPORTANT IN REGULATING THE WINTER WEATHER IN THE NORTHERN HEMISPHERE. view more 

CREDIT: CC-0 NASA

Migrating storms and local weather systems known as cyclones and anticyclones were thought to contribute to behaviors and properties of our global weather system. However, the means to probe cyclones and anticyclones were limited. For the first time, researchers demonstrated a new three-dimensional analytical methodology that can quantify the way individual cyclones and anticyclones impact broader weather systems. This study aids longer-term circulation and climate studies, including how storm characteristics may change in the future.

To many people, the term cyclone probably conjures up images of ferocious storm winds or the tornadoes central to the plot of the Wizard of Oz. However, cyclones, and anticyclones, are a broader set of large-scale weather phenomena that are, as it turns out, crucial to the way our global climate functions. Cyclones are simply systems of winds rotating around an area of low air pressure. These tend to indicate rainy or stormy weather and rotate clockwise south of the equator and counterclockwise to the north. Anticyclones conversely are weather systems rotating around areas of high pressure and tend to indicate calmer and sunnier weather. These rotate the opposite way to cyclones in either hemisphere.

"For decades now, atmospheric scientists have used a technique known as the Eulerian approach (named after 18th-century mathematician Leonhard Euler) to analyze long-term three-dimensional atmospheric data," said Project Research Associate Satoru Okajima from the Research Center for Advanced Science and Technology (RCAST) at the University of Tokyo. "However, the approach considers cyclones and anticyclones to be merely deviations from a background average, and not separate entities in their own right. Furthermore, anticyclones are often unconsciously disregarded, unlike cyclones, possibly because of their association with calmer weather."

Okajima, Professor Hisashi Nakamura from RCAST and Professor Yohai Kaspi from the Weizmann Institute of Science in Israel, adopted a novel technique to isolate data from winds rotating around an area of low or high air pressure from ever-present background winds such as the westerly jet stream, the fast-flowing air currents between 30 degrees and 60 degrees latitude in both hemispheres. This approach allowed the team to evaluate the effect local curvature, essentially the shape, of cyclones and anticyclones had on the westerly jet stream. This is in contrast to one of the previous standard ways to view these patterns called relative vorticity, which could not reveal such fine details.

"It was extremely challenging to quantitatively separate the cyclones from the anticyclones, and many attempts along the way fell flat. But our successful method can now be applied to various climate-model simulations and will hopefully help researchers better project the future of our warming climate," said Okajima. "Climate science is important to all of us as it affects so many things. But it is also particularly interesting as it combines so many subfields like oceanography, hydrology, computer science, physics, chemistry and mathematics. I hope our contribution can be a useful tool to climate scientists for making predictions about our ever-changing world."

CAPTION

The upper contour map shows a model of the cyclones and anticyclones superimposed on the westerly jet stream according to the previous standard for modeling cyclones, relative vorticity. The lower contour map shows the same, but uses the team's new method, based on local curvature or shape.

CREDIT

©2021 Okajima et al.

Journal article

Satoru Okajima, Hisashi Nakamura & Yohai Kaspi, "Cyclonic and anticyclonic contributions to atmospheric energetics" Scientific Reports, DOI: 10.1038/s41598-021-92548-7

Link: http://www.nature.com/articles/s41598-021-92548-7

Funding

This study is supported in part by the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) through the Arctic Challenge for Sustainability II (ArCSII; JPMXD1420318865), by the Japan Science and Technology Agency through COI-NEXT JPMJPF2013, by the Japanese Ministry of Environment through Environment Research and Technology Development Fund JMEERF20192004, and by the Japan Society for the Promotion of Science (JSPS) through Grants-in-Aid for Scientific Research JP18H01278, JP19H05702 (on Innovative Areas 6102) and 20H01970. Y.K. acknowledges support from the JSPS Invitational Fellowship for Research in Japan that supported a sabbatical at the University of Tokyo and ignited this collaboration, for support from the Research Center for Advanced Technology and Science at the University of Tokyo and the Israeli Science Foundation (grant 996/20).

Useful links

Research Center for Advanced Science and Technology

https://www.rcast.u-tokyo.ac.jp/en/index.html

Hisashi Nakamura Laboratory

https://www.atmos.rcast.u-tokyo.ac.jp/nakamura_lab/en/

Yohai Kaspi Laboratory at the Weizmann Institute of Science, Israel

https://www.weizmann.ac.il/EPS/kaspi/

 

Coincidence? I think so: researchers use phylogenetics to untangle convergent adaptation in birds

SKOLKOVO INSTITUTE OF SCIENCE AND TECHNOLOGY (SKOLTECH)

Research News

 

Researchers from Skoltech and their colleagues have shown that adaptation to similar environments hardly involves similar genomic positions when species are distantly related. The team investigated recurrent adaptations of wildlife birds' mitochondria to high altitude, migration, diving, wintering, and flight. Repeatable substitutions are rather a coincidence than adaptation, which confirms the scientific opinion that distant species "choose" different ways of similar trait evolution. The paper was published in the journal Genome Biology and Evolution.

If an organism wants to survive in unusual conditions, such as oxygen starvation typical for high altitudes or elevation of metabolism rate due to extreme temperatures, it has to adapt. If different species meet similar environment conditions, they will adapt independently and could even do it by same substitutions in identical genomic positions - this is called single-position molecular convergence.

"Convergent evolution is one of most fascinating topics of evolutionary biology: from a practical point of view, it helps to find particular genomic positions associated with adaptation; from a more theoretical one, it shows how repeatable evolution is. Yet detection of adaptive convergent single-position mutations is known to be hard, especially in phylogenetically distant species: scientists continue to argue about whether it is possible at all," Skoltech PhD graduate Valentina Burskaia says.

Burskaia, Professor Georgii Bazykin and their colleagues designed an unusually large dataset of 415 species in which similar traits appear independently dozens of times. The dataset allowed them to examine the problem deeply, as previous attempts to detect convergent single-nucleotide mutations in phylogenetically distant species were often limited by few numbers of convergent phenotype acquisitions.

"Mitochondrial genome was chosen for the study as it is small and thus sequenced for many species, yet full of extremely important genes. Mitochondrial genes are responsible for hypoxia and metabolism level tuning: this guided our selection of phenotypic traits of interest," Burskaia notes.

The team looked at birds who live at high altitudes and diving birds (likely to face hypoxia). To study adaptations which affect metabolism rate changes, scientists considered four groups of species: birds with outstanding flight abilities, long-distance migrants, flightless birds and wintering birds. By running powerful phylogenetic methods, where species are placed on a "tree" and coincident changes in phenotype and genotype are counted, the researchers were able to show that the majority of convergence events can be explained by random coincidences rather than adaptation.

The study, being conceptually close to recent attempts to search for single-position convergences in echolocating bats and marine mammals, confirms that evolutionary landscape at between-order distances is too different for single-position adaptive convergence.

Other organizations involved in this research include Lomonosov Moscow State University, Kharkevich Institute for Information Transmission Problems of the Russian Academy of Sciences, and Hong Kong University of Science and Technology.

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Skoltech is a private international university located in Russia. Established in 2011 in collaboration with the Massachusetts Institute of Technology (MIT), Skoltech is cultivating a new generation of leaders in the fields of science, technology and business, is conducting research in breakthrough fields, and is promoting technological innovation with the goal of solving critical problems that face Russia and the world. Skoltech is focusing on six priority areas: data science and artificial intelligence, life sciences, advanced materials and modern design methods, energy efficiency, photonics and quantum technologies, and advanced research. Web: https://www.skoltech.ru/.

 

Feel-good hormone dopamine affects passion and autism

Dopamine may help explain the prevalence of traits and conditions more commonly seen in males

NORWEGIAN UNIVERSITY OF SCIENCE AND TECHNOLOGY

Research News

 

Men - more often than women - need passion to succeed at things. At the same time, boys are diagnosed as being on the autism spectrum four times as often as girls.

Both statistics may be related to dopamine, one of our body's neurotransmitters.

"This is interesting. Research shows a more active dopamine system in most men" than in women, says Hermundur Sigmundsson, a professor at the Norwegian University of Science and Technology's (NTNU)Department of Psychology.

He is behind a new study that addresses gender differences in key motivating factors for what it takes to become good at something. The study uses men's and women's differing activity in the dopamine system as an explanatory model.

"We looked at gender differences around passion, self-discipline and positive attitude," Sigmundsson says.

The study refers to these qualities as passion, grit and mindset. The researchers also applied theories to possible links with dopamine levels.

Dopamine is linked to learning, attention and our ability to focus.

Dopamine is a neurotransmitter that is released in the brain. It can contribute to a feeling of satisfaction.

Men normally secrete more dopamine, which is often called the "happy hormone," but it plays a far more complex role than that. The effects of dopamine are linked to learning, attention and our ability to focus.

Previous studies on Icelandic students have shown that men are more dependent on passion in order to succeed at something. This study confirms the earlier findings. Men require more passion. In six out of eight test questions, men score higher on passion than women.

However, the association with dopamine levels has not been established previously.

"The fact that we've developed a test to measure passion for goal achievement means that we can now relate dopamine levels to passion and goal achievement," says Sigmundsson.

Women, on the other hand, may have greater self-discipline - or grit - and be more conscientious, according to other studies. Their level of passion may not be as pronounced in general, but they still are able to do what it takes to be good.

The results for the women, however, are somewhat more ambiguous than men's strong need to burn for something, and this study found no such gender difference.

Nor did the researchers find any difference between the sexes in terms of growth mindset.

In the past, the dopamine system has been associated with many different conditions, such as ADHD, psychoses, manias and Parkinson's disease. But it may also be related to a certain form of autistic behaviour.

Some individuals with autism may become very interested in certain topics, which can be a bit unusual, or even strange, for most people. People on the autism spectrum can focus intensely on these topics or pursuits, at least for a while. Dopamine may play a role.

"Other research in neuroscience has shown hyperactivity in the dopamine system in individuals with autism, and boys make up four out of five children on the autism spectrum. This, and dopamine's relationship to passion, might be a mechanism that helps to explain this behaviour," says Sigmundsson.

The research group tested 917 people aged 14 to 77, consisting of 502 women and 415 men. This is considered a major study in this context.

Sigmundsson collaborated with Stéfan Guðnason from the University of Akureyri and Sigurrós Jóhannsdóttir from the Icelandic State Diagnostic and Counselling Centre (SDCC).

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Reference: Hermundur Sigmundsson, StéfanGuðnason, Sigurrós Jóhannsdóttir. Passion, grit and mindset: Exploring gender differences. Science Direct. Available online 3 June 2021. https://doi.org/10.1016/j.newideapsych.2021.100878

 

Plant Protector: How plants strengthen their light-harvesting membranes against environmental stress

HELMHOLTZ ZENTRUM MÜNCHEN - GERMAN RESEARCH CENTER FOR ENVIRONMENTAL HEALTH

Research News

 

IMAGE: ARTISTIC RENDERING OF THE VIPP1 RING STRUCTURE COVERED IN LUSH PLANT LIFE, REPRESENTING THE CENTRAL ROLE OF VIPP1 IN CONSTRUCTING AND MAINTAINING THE PHOTOSYNTHETIC THYLAKOID MEMBRANES THAT ENABLE PLANTS TO... view more 

CREDIT: © HELMHOLTZ ZENTRUM MUENCHEN / BEN ENGEL

An international study led by Helmholtz Zentrum München has revealed the structure of a membrane-remodeling protein that builds and maintains photosynthetic membranes. These fundamental insights lay the groundwork for bioengineering efforts to strengthen plants against environmental stress, helping to sustaining human food supply and fight against climate change.

Plants, algae, and cyanobacteria perform photosynthesis, using the energy of sunlight to produce the oxygen and biochemical energy that power most life on Earth. They also adsorb carbon dioxide (CO?) from the atmosphere, counteracting the accumulation of this greenhouse gas. However, climate change is exposing photosynthetic organisms to increasing environmental stress, which inhibits their growth, and in the long term, endangers the food supply of humankind.

The important first steps of photosynthesis are performed within the thylakoid membranes, which contain protein complexes that harvest sunlight. For decades, it has been known that the protein VIPP1 (vesicle-inducing protein in plastids) is critical for forming thylakoid membranes in almost all photosynthetic organisms - from plants on land to algae and cyanobacteria in the ocean. However, it has remained a mystery how VIPP1 performs this essential function. In the latest issue of the journal Cell, a new study by an international consortium of researchers led by Ben Engel from the Helmholtz Pioneer Campus at Helmholtz Zentrum München reveals the structure and mechanism of VIPP1 with molecular detail.

Building and protecting photosynthetic membranes

The researchers used cryo-electron microscopy to generate the first high-resolution structure of VIPP1. Combining this structural analysis with functional assays revealed how VIPP1 assembles into an interwoven membrane coat that shapes the thylakoid membranes. The research group also used the cutting-edge approach of cryo-electron tomography to image VIPP1 coats within the native environment of algae cells. By using the structural information to make specific mutations to VIPP1, the researchers observed that the interaction of VIPP1 with thylakoid membranes is critical to maintain the structural integrity of these membranes under high-light stress. "Our study shows how VIPP1 plays a central role in both thylakoid biogenesis and adaptation of thylakoids to environmental changes," explains first author Tilak Kumar Gupta from the Max Planck Institute of Biochemistry.

This study lays the foundation for a mechanistic understanding of thylakoid biogenesis and maintenance. It also provides new opportunities for engineering plants that are more resistant to extreme environmental conditions. "Insights into the molecular mechanisms controlling thylakoid remodeling are an important step towards developing crops that not only grow faster, have higher yield and resistance to environmental stress, but also absorb more atmospheric CO? to counteract climate change," says study leader Ben Engel.

International team research

This interdisciplinary study brought together the talents of research teams from the Technische Universität Kaiserslautern (Michael Schroda), Philipps-Universität Marburg (Jan Schuller), Ludwig-Maximilians-Universität München (Jörg Nickelsen), Okayama University in Japan (Wataru Sakamoto), McGill University in Canada (Mike Strauss), Ruhr-Universität Bochum (Till Rudack), the Max Planck Institute of Biochemistry (Wolfgang Baumeister and Jürgen Plitzko) and Helmholtz Zentrum München. "Our study covers a lot of new ground using a wide variety of techniques. This was only possible thanks to the tremendous collective efforts of the researchers in our international consortium," says Ben Engel.

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