Brain

Hamilton, ON (May 10, 2021) - It is well known that each person's gut bacteria is vital for digestion and overall health, but when does that gut microbiome start?

New research led by scientists from McMaster University and Charité - Universitätsmedizin Berlin in Germany has found it happens during and after birth, and not before.

McMaster researchers Deborah Sloboda and Katherine Kennedy examined prenatal stool (meconium) samples collected from 20 babies during breech Cesarean delivery.

"The key takeaway from our study is we are not colonized before birth. Rather, our relationship with our gut bacteria emerges after birth and during infancy," said Kennedy, first author of the study and a PhD student, whose findings are published in Nature Microbiology.

Recent studies have sparked controversy by claiming that we are colonized by gut bacteria before birth. But, Kennedy said, studies such as these have been criticized for the ways they control for contamination.

"By including only breech caesarean deliveries in healthy pregnant women we were able to avoid the transmission of bacteria that occurs naturally during a vaginal birth," said Thorsten Braun, co-senior author and lead obstetric consultant and deputy director of the Department of 'Experimental Obstetrics' at Charité - Universitätsmedizin Berlin.

Kennedy said recent data suggest that a person's relationship with their own gut bacteria is most important in early life, during critical stages of immunological and physiological development.

Sloboda, co-senior author, agrees.

"The fact that colonization of infants' guts occurs during and after their births, means that not only is it vulnerable to early environmental influences, but could also offers a window of potential intervention," said Sloboda, professor of biochemistry and biomedical sciences at McMaster and the Canada Research Chair in perinatal programming.

"While many of the exact mechanisms surrounding gut bacteria and their role in our early development is unclear, discovering when and how we are colonized is a key first step."

ATLANTA--Gestures--such as pointing or waving--go hand in hand with a child's first words, and twins lag behind single children in producing and using those gestures, two studies from Georgia State University psychology researchers show.

Twins produce fewer gestures and gesture to fewer objects than other children, said principal researcher Seyda Ozcaliskan, an associate professor in the Department of Psychology. Language use also lags for twins, and language--but not gesture--is also affected by sex, with girls performing better than boys, Ozcaliskan said.

"The implications are fascinating," said Ozcaliskan. "It shows that gesture and speech go hand in hand in early development in twins. When one is lagging behind so does the other."

The research found that a lag in gesture can reliably predict a lag in speech. At the same time, lots of gesturing suggests speech is on the way. Parents can help speed their child's acquisition of language by naming the objects they gesture to.

The lag in gesture among twins may be due to lower parental input, Ozcaliskan said, for parents of single children used a greater amount and diversity of gestures than parents of twins. It's likely, Ozcaliskan said, that parents caring for twins engage in shorter conversations with their children, including gesturing less, because their attention is divided and their labor is doubled.

The studies were conducted by Ozcaliskan and her psychology doctoral students Ebru Pinar and Sumeyra Ozturk, along with her collaborator Dr. Nihan Ketrez in Istanbul. The paper Parental Speech and Gesture Input to Girls Versus Boys in Singletons and Twins was published in the Journal of Nonverbal Behavior and Effect of Sex and Dyad Composition on Speech and Gesture Development of Singleton and Twin Children was published in the Journal of Child Language. The two studies analyzed video data from Turkish families and included three groups of fraternal twins--males, females and mixed sex twins, as well as two groups of single boys and girls, along with their parents.

Ozcaliskan said she had grown curious about gesture because it had not yet been studied among twins, while language acquisition has been thoroughly researched.

"We've known for a long time that children's early vocabulary shows sex differences," said Ozcaliskan, "with boys having smaller vocabularies than girls their age."

Girls age 2-3 also produce longer, more complex sentences than boys. Twins are initially at a disadvantage where language is concerned, using fewer words than their singleton peers and forming complete sentences later than singletons. Boys lag the most, with girl-girl twins developing larger vocabularies and more complex sentences than boy-boy twins of comparable age.

Most of the time, these lags are within the normal range of differences, and nothing to worry about. Almost all children will catch up to each other by around age three and a half.

But what about gesture?

"There was close to nothing in research on gesturing among twins in any language," Ozcaliskan said.

Infants start using pointing around 10 months, a few months before they produce their first words. In other words, they point at a dog a few months before they actually say the word "dog." Gesture helps them convey what they can't yet communicate in speech and paves the way for children's early words.

Though the lag in gesture and language among twins may be mostly due to reduced parental input, Ozcaliskan said twins sometimes develop their own systems of communication, even their own "twin language," which has been shown to delay language acquisition. "Perhaps it also delays the use of gestures," she said.

On most occasions, a lag in gesture may mean a lag in the next linguistic milestone.

"However, in the event that you see the lag in gesture go on for a long time, it may be a marker of a potential developmental or language delay," said Ozcaliskan. On the other hand, if a child doesn't talk much at an early age, but frequently uses gesture, a parent can be reassured that "language is on its way," she said.

The more a parent engages with a child, using gesture and speech, the better the child's acquisition of both. Gesture and speech together form a closely integrated system in a child's development, and a child's first gestures often precede their first attempts at speech.

For parents who are intrigued by these connections, Ozcaliskan suggested naming objects when children point to them, as in: Yes, that's a bottle, do you want your bottle? Naming helps children learn new words earlier. Parents can also make a point of gesturing to objects themselves when naming.

"Gesture is a very powerful tool," Ozcaliskan said. "Pay attention to your child's gestures, and then provide verbal descriptions to help their language development."

The use of multimode optical fibers to boost the information capacity of the Internet is severely hampered by distortions that occur during the transmission of images because of a phenomenon called modal crosstalk.

However, University of Rochester researchers at the Institute of Optics have devised a novel technique, described in a paper in Nature Communications, to "flip" the optical wavefront of an image for both polarizations simultaneously, so that it can be transmitted through a multimode fiber without distortion. Researchers at the University of South Florida and at the University of Southern California collaborated on the project.

Lead author Yiyu Zhou, a PhD candidate in the Rochester lab of Robert Boyd, professor of optics, draws an analogy to a multilane highway in describing the challenge the researchers confronted.

"Obviously, a multiple lane highway is faster than a single lane," Zhou says. "But if a courier is forced to change from lane A to lane B, the package will be delivered to the wrong destination. When this happens in a multimode fiber--when one spatial mode is coupled to another during the propagation through the fiber--it's what we call modal crosstalk. And we want to suppress that."

The solution the researchers devised involves digitally pre-shaping the wavefront and polarization of a forward-propagating signal beam to be the phase conjugate of an auxiliary, backward-propagating probe beam--in an experimental realization of vectorial time reversal.

"When an optical beam with perfect wavefronts passes through the multimode fiber, it comes out badly distorted," explains Boyd, who is also the Canada Excellence Research Chair in Quantum Nonlinear Optics at the University of Ottawa.

"If we use a mirror to send the wavefront back, it will become even more distorted. But if we instead reflect it off a mirror, and also flip the wavefront from front to back, the distortion becomes undone as the waves go back through that distorting medium. In particular, we need perform this procedure for both polarizations simultaneously when the distorting medium is a long multimode fiber."

The researchers demonstrate that this technology can enhance the channel capacity in a 1-km-long multimode fiber

"Our technique can be used to realize mode-division multiplexing over long, standard multimode fibers to significantly enhance the channel capacity of optical communication links," Zhou says. "It can potentially be used to increase the Internet speed by one or two orders of magnitude."

The technique could also be potentially used to improve endoscopy imaging of the brain and other biological tissues, Zhou says.

DALLAS, May 10, 2021 — Managing weight, blood pressure and cholesterol in children may help protect brain function in later life, according to new research published today in the American Heart Association’s flagship journal Circulation. This is the first study to highlight that cardiovascular risk factors accumulated from childhood through mid-life may influence poor cognitive performance at midlife.

Previous research has indicated that nearly 1 in 5 people older than 60 have at least mild loss of brain function. Cognitive deficits are known to be linked with cardiovascular risk factors, such as high blood pressure, obesity, type 2 diabetes, smoking, physical inactivity and poor diet, as well as depression and low education level.

Many diseases that cause neurological deficits, such as Alzheimer’s, have a long preclinical phase before noticeable symptoms begin, so finding links between childhood obesity and other cardiovascular risk factors is important for cognitive health. The researchers noted that there are currently no cures for major causes of dementia, so it is important to learn how early in life cardiovascular risk factors may affect the brain.

“We can use these results to turn the focus of brain health from old age and midlife to people in younger age groups,” said the study’s first author Juuso O. Hakala, M.D., a Ph.D. student at the Research Centre of Applied and Prevention Cardiovascular Medicine at the University of Turku, in Turku, Finland. ”Our results show active monitoring and prevention of heart disease and stroke risk factors, beginning from early childhood, can also matter greatly when it comes to brain health. Children who have adverse cardiovascular risk factors might benefit from early intervention and lifestyle modifications.”

The Cardiovascular Risk in Young Finns Study is a national, longitudinal study on cardiovascular risk from childhood to adulthood in Finland. Researchers followed the participants’ cardiovascular risk factor profiles for 31 years from childhood to adulthood. Baseline clinical examinations were conducted in 1980 on approximately 3,600 randomly selected boys and girls, ranging in ages from 3 to 18, all of whom were white. More than 2,000 of the participants, ranging in ages from 34 to 49, underwent a computerized cognitive function test in 2011. The test measured four different cognitive domains: episodic memory and associative learning; short-term working memory; reaction and movement time; and visual processing and sustained attention.

Researchers found:

Systolic blood pressure, total blood cholesterol and low-density lipoprotein (LDL) cholesterol, as well as body mass index, from childhood to midlife are associated with brain function in middle age.
Consistently high systolic blood pressure or high blood total cholesterol and LDL cholesterol were linked to worse memory and learning by midlife when compared with lower measures.
Obesity from childhood to adulthood was associated with lower visual information processing speed and maintaining attention.
Having all three cardiovascular risk factors was linked to poorer memory and associative learning, worse visual processing, decreased attention span, and slower reaction and movement time.

These results are from observational findings, so more studies are needed to learn whether there are specific ages in childhood and/or adolescence when cardiovascular risk factors are particularly important to brain health in adulthood. Study limitations include that a definite cause-and-effect link between cardiovascular risk factors and cognitive performance cannot be determined in this type of population-based study; cognition was measured at a single point in time; and because all study participants are white, the results may not be generalizable to people from other racial or ethnic groups.

In 2020, the American Heart Association partnered with Nemours, a nonprofit pediatric health system, to create Healthy Way to Grow – a national, science-based, early childhood technical assistance program to help improve practices and policies to prevent childhood obesity.

Researchers have successfully developed a new Strep A human challenge model, paving the way to test vaccines against the common deadly bacteria that causes sore throats, scarlet fever and skin sores.

The collaborative research effort, led by the Murdoch Children's Research Institute (MCRI) and published in The Lancet Microbe, found the model, which deliberately infected healthy adult volunteers with the bacteria in a controlled environment, was safe and would now be used to trial Strep A candidate vaccines.

Strep A infections affect about 750 million people and kill more than 500,000 globally every year - more than influenza, typhoid or whooping cough. Strep A can also cause severe life-threatening infections like toxic shock syndrome and flesh eating disease and post-infectious illnesses such as acute rheumatic fever, rheumatic heart disease and kidney disease.

Strep A infections disproportionately affect young children, the elderly, pregnant women and Indigenous Australians. There is currently no vaccine available to prevent Strep A and can only potentially be treated with antibiotics.

MCRI'S Dr Josh Osowicki said given Strep A only naturally infected humans, researchers were limited in what they could learn in the lab and using animal models.

"Human challenge models can be used to test vaccines, drugs and diagnostic tests, as well as driving all sorts of wonderful scientific collaborations to understand more about how diseases work and how to stop them," he said.

"We have developed the only current Strep A controlled human infection model, ready to be used as a platform to evaluate new vaccine candidates and therapeutics."

Dr Osowicki said the research team tested a Strep A strain they believed would cause a strep throat and was unlikely to cause acute or chronic health problems.

The study involved 25 volunteers, aged 18-40 years who stayed at Nucleus Network, a phase 1 clinical trials unit based in Melbourne for up to six days with blood tests and saliva and throat swabs collected regularly.

Dr Osowicki said 85 per cent of participants developed a convincing case of strep throat, well up on the at least 60 per cent anticipated.

"Starting at one-tenth of the dose used in old 1970s studies, we applied our special Strep A strain on the back of each participant's throat," he said. "To our surprise, from the very first participant at the low starting dose, our strain caused strep throat in most participants."

The volunteers developed mild to moderate symptoms including a sore throat, sweats, fever and headache. All quickly recovered and were followed up for six months after they were sent home, according to the study.

Melbourne resident Tania O'Meara's daughter Eden was just 11 months old when she almost lost her leg to a flesh-eating bacterial infection caused by Strep A.

"We put our daughter to bed with what seemed like a cold but the next morning she woke up with a fever and was very pale, limp and dehydrated," she said.

"We took her to the hospital but the doctor couldn't get the IV drip in because Eden was so dehydrated and they were forced to drill it into her leg. They also noticed that the skin on her leg looked like it was turning a different colour."

Ms O'Meara said Eden required surgery on her right calf to remove the dead flesh.

"We were told that she could die and we braced ourselves so it was a miracle that they were able to save her leg and even her calf muscle," she said.

Eden, now three, needed three more surgeries and has since made a full recovery.

Ms O'Meara said she was relieved that a vaccine for Step A may not be too far away.

"I don't want any other family to experience what we went through. It is an absolute tragedy that this bacteria is cutting so many lives short," she said.

MCRI Professor Andrew Steer said the team expected to start testing candidate Strep A vaccines developed by researchers in Australia and overseas before the end of the year.

The trials, to be conducted in Melbourne, would involve about 50 participants receiving a candidate vaccine or placebo and having the Strep A challenge strain applied on their throats.

"The global burden of Strep A is an unmet public health challenge. We hope this research will accelerate the development of a vaccine and move things forward to bigger field trials," Professor Steer said.

"A vaccine for Strep A will save hundreds of thousands of lives every year and prevent millions of infections that send children and adults to the hospital or doctor."

The two meters of -stretched- DNA contained in human cells are continuously twisting and untwisting to give access to genetic information: when a gene is expressed to generate a protein, the two strands of DNA are separated to give access to all the machinery necessary for this expression, resulting in an excessive accumulation of coiling that needs to be resolved later. The paper that has now been published by the team led by Felipe Cortés, head of the DNA Topology and Breaks Group at the Spanish National Cancer Research Centre (CNIO), in collaboration with Silvia Jimeno González, professor at the University of Seville and head of the mRNA Transcription and Processing Group at the Andalusian Centre for Molecular Biology and Regenerative Medicine (CABIMER), shows that this supercoiling characteristic of DNA's structure controls gene expression rather than being a mere collateral damage to be solved, as had been thought to date. The results are reported in the journal Cell Reports.

"These results are a first step towards understanding supercoiling as an important regulator of the genome and not only as a problem associated with the metabolism of DNA," says Cortés.

According to the paper's authors, this regulation occurs mainly on specific genes, namely those that are induced very quickly, hundreds of times in only a few minutes, such as the genes that respond to stress, cell proliferation signals, hormones or those involved in neuronal stimulation.

TOP2A, regulator of the expression of immediate response genes.

Topoisomerases are proteins that act on DNA, relaxing this topological stress by eliminating both an excess (positive supercoiling) and a defect (negative supercoiling) in the number of turns of the double helix compared to its normal relaxed structure.

The researchers demonstrated in this study that topoisomerase TOP2A eliminates negative supercoiling at gene promoters, thereby causing an increase in the number of turns of DNA strands in these regions. This hinders the opening of the double helix, preventing the RNA polymerase from advancing and leaving it ready to quickly trigger gene activation when required by the cell.

"Topoisomerases are considered gene activation facilitators, although here we demonstrate that topoisomerase TOP2A acts in the promoter regions of genes such as c-FOS [cell proliferation regulator] to keep them repressed, but creating a particular topological context that allows them to be activated quickly in order to provide an immediate response to stimuli," says Cortés.

The researchers also advance the possibility of other functions of DNA supercoiling, such as facilitating a three-dimensional conformation of the genome favouring interactions between regulatory elements for gene expression.

This new form of genomic regulation through supercoiling highlights its potential involvement in processes that are fundamental to cell function and that require profound changes in gene expression programmes, such as cell differentiation or reprogramming, as well as in tumour transformation and progression.

"The paper also opens up the possibility of using topoisomerase inhibitors to modulate these processes and cellular responses, and perhaps even as possible anti-tumour therapies," concludes Cortés.

The research was funded by the Ministry of Science and Innovation, the Carlos III Health Institute, the Government of Andalusia, the European Research Council and the Spanish Association Against Cancer.

Nanofabrication of electronic devices has reached a single nanometer scale (10-9 m). The rapid advancement of nanoscience and nanotechnology now requires atomic-scale optical spectroscopy in order to characterize atomistic structures that will affect the properties and functions of the electronic devices.

The international team headed by Takashi Kumagai at Institute for Molecular Science discovered a huge enhancement of Raman scattering mediated by a formation of an atomic point contact between a plasmonic silver tip and a Si(111)-7×7 reconstructed surface. This was achieved by means of state-of-the-art low-temperature tip-enhanced Raman spectroscopy which allows to conduct atomic-scale vibrational spectroscopy.

The discovered enhancement mechanism of Raman scattering will open the possibility of atomic-scale ultrasensitive vibrational spectroscopy to investigate surface structures of semiconductors. In addition, the developed atomic-scale optical microscopy will pave the way for exploring atomic-scale light-matter interactions, leading to a new discipline in light science and technology.

Super integration of electronic devices has entered a single nanometer scale, calling for analytical methods that can investigate atomic-scale structures and defects in detail. The advancement of scanning near-field optical microscopy has allowed nanoscale imaging and chemical analyses at the nanoscale. More recently, the spatial resolution of this technique was demonstrated to reach the atomic scale. In particular, tip-enhanced Raman spectroscopy has drawn increasing attention as ultrasensitive chemical microscopy. However, in order to obtain a Raman signal from semiconductor surfaces, it was necessary to further enhance the sensitivity.

The research team applied state-of-the-art low-temperature tip-enhanced Raman spectroscopy, developed in collaboration with Fritz-Haber Institute, to obtain the vibration spectra from a silicon surface. Tip-enhanced Raman spectroscopy employs a strong light-matter interaction between a material and nanoscale light (localized surface plasmon resonance) generated at an atomically sharp metallic tip. The research team discovered that an atomic point contact formation of a silver tip and a reconstructed Si(111)-7×7 surface leads to a huge enhancement of Raman scattering. Figure 1a illustrates the experiment. A sharp silver tip fabricated by focused ion beam (figure 1b, top) is moved toward the silicon surface (figure 1b, bottom), while monitoring the Raman spectra from the junction. Figure 1c displays the waterfall plot of the obtained Raman spectra, where the horizontal axis the Raman shift, and the color scale the Raman intensity. When the tip is in the tunneling regime, only the optical phonon mode of the bulk silicon is observed at 520 cm-1. However, when the atomic point contact between the tip and the surface, the strong Raman scattering from the surface phonon modes suddenly appears. These modes disappear again when the tip is moved away from the surface and the atomic point contact is broken.

The research team further demonstrated that this atomic point contact Raman spectroscopy (APCRS) can resolve the atomic-scale structures of the silicon surface. As shown in figure 2, the Raman spectrum is different when it is recorded at an atomic step of the surface. Furthermore, the characteristic vibration modes can be observed selectively at the locally oxidized site (figure 3), indicating the atomic-scale chemical sensitivity of atomic-point-contact Raman spectroscopy.

It was previously thought that a plasmonic nanogap is necessary to obtain the ultrahigh sensitivity in tip-enhanced Raman spectroscopy, which typically requires a metal substrate. This imposed a severe limitation on measurable samples. The discovery of the huge Raman enhancement upon the atomic point contact formation will expand the potential of atomic-scale vibration spectroscopy, which is applicable to non-plasmonic samples and the exceptional chemical sensitivity will be obtained for many other materials. In addition, our results also suggest that atomic scale structures play an indispensable role in metal-semiconductor hybrid nanosystems to affect their optoelectronic properties.

ITHACA, N.Y. - An 18.5 million-year-old fossil found in Panama provides evidence of a new species and is the oldest reliable example of a climbing woody vine known as a liana from the soapberry family. The discovery sheds light on the evolution of climbing plants.

The new species, named Ampelorhiza heteroxylon, belongs to a diverse group of tropical lianas called Paullinieae, within the soapberry family (Sapindaceae). More than 475 species of Paullinieae live in the tropics today.

Researchers identified the species from fossilized roots that revealed features known to be unique to the wood of modern climbing vines, adaptations that allow them to twist, grow and climb.

The study, "Climbing Since the Early Miocene: The Fossil Record of Paullinieae (Sapindaceae)," was published April 7 in the journal PLOS ONE.

"This is evidence that lianas have been creating unusual wood, even in their roots, as far back as 18 million years ago," said wood anatomist Joyce Chery '13, assistant research professor in the School of Integrative Plant Science, Plant Biology Section, in the College of Agriculture and Life Sciences, and a corresponding author of the paper.

"Before this discovery, we knew almost nothing about when or where these lianas evolved or how rapidly they diversified," said first author Nathan Jud, assistant professor of plant biology at William Jewell College and a former Cornell postdoctoral researcher.

Panama was a peninsula 18.5 to 19 million years ago, a volcanic landscape covered with tropical forest in North America and separated from South America by a Central American seaway. While these forests contained North American animals, the plants mostly descended from South American tropical plants that had dispersed across the seaway, Jud said.

"The fossil we described is the oldest macrofossil of these vines," he said, "and they were among the plants that made it to North America long before the Great American Biotic Interchange when large animals moved between the continents some 3 million years ago."

In the study, the researchers made thin slices of the fossil, examined the arrangements and dimensions of tissues and water conducting vessels under a microscope and created a database of all the features. They then studied the literature to see how these features matched up with the living and fossil records of plants.

"We were able to say, it really does look like it's a fossil from the Paullinieae group, given the anatomical characteristics that are similar to species that live today," Chery said.

During their analyses, the researchers identified features that are characteristic of lianas. Most trees and shrubs have water-conducting tissues (which transport water and minerals from roots to leaves) that are all roughly the same size when viewed in a cross-section; in vines, these conduits come in two sizes, big and small, which is exactly what the researchers discovered in the fossil.

"This is a feature that is pretty specific to vines across all sorts of families," Chery said.

The two vessel sizes provide insurance for a twisting and curving plant, as large vessels provide ample water flow, but are also vulnerable to collapse and develop cavities that disrupt flow. The series of smaller vessels offers a less vulnerable backup water transport system, Chery said.

Also, cross-sections of the wood in trees and shrubs are circular, but in the fossil, and in many living vines, such cross-sections are instead irregular and lobed.

Thirdly, on the walls of those vascular vessels, they found long horizontal perforations that allow for water to flow in lateral directions. That is a distinguishing feature of lianas in the soapberry family, Chery said.

In future work, now that they can place the lianas of Sapindaceae to 18.5 million years ago, the researchers intend to continue their investigation of the evolutionary history and diversification of this family. Chery also plans to investigate how wood has evolved in this group of vines, including identifying the genes that contribute to lobe-shaped stems.

Young and middle-aged adults who reported severe psychological distress--such as depression or anxiety--after suffering a heart attack were more than twice as likely to suffer a second cardiac event within five years compared with those experiencing only mild distress, according to a study presented at the American College of Cardiology's 70th Annual Scientific Session.

The study is the first to comprehensively assess how mental health influences the outlook for younger heart attack survivors, according to the researchers. The researchers also tracked inflammatory markers that appear to have a role in increasing cardiovascular risk among people experiencing distress. The findings align with previous studies focusing on older adults, bolstering the evidence for mental health as an integral part of a person's recovery after a heart attack.

"Our findings suggest that cardiologists should consider the value of regular psychological assessments, especially among younger patients," said Mariana Garcia, MD, a cardiology fellow at Emory University in Atlanta and the study's lead author. "Equally importantly, they should explore treatment modalities for ameliorating psychological distress in young patients after a heart attack, such as meditation, relaxation techniques and holistic approaches, in addition to traditional medical therapy and cardiac rehabilitation."

The researchers analyzed health outcomes in 283 heart attack survivors between the ages of 18 and 61, with an average age of 51 years. Study participants completed a series of validated questionnaires measuring depression, anxiety, anger, perceived stress and posttraumatic stress disorder within six months of their heart attack. Based on these questionnaires, the researchers established a composite score of psychological distress for each participant and grouped patients based on experiences of mild, moderate and high distress.

Within five years after their heart attack, 80 of the 283 patients suffered a subsequent heart attack or stroke, were hospitalized for heart failure or died from cardiovascular causes. These outcomes occurred in nearly half (47%) of patients experiencing high distress compared to 22% of those experiencing mild distress.

Previous studies suggest inflammation is one mechanism through which psychological distress may lead to heart problems. In the new study, patients who experienced high distress were also found to have higher levels of two inflammatory markers--interleukin-6 and monocyte chemoattract protein-1--in their blood during rest and after mental stress. These markers, which increase during times of mental stress, are known to be associated with plaque buildup in the arteries and adverse cardiac events.

"It is thought that those who have had a heart attack may be particularly vulnerable to plaque rupture as a result of these inflammatory mechanisms at play," Garcia said. "The association we found was independent of known cardiovascular risk factors and suggests mechanisms involving systemic inflammation in response to stress may be implicated in the likelihood of a subsequent cardiac event."

The researchers also found that patients with high distress were more often Black, female and from a disadvantaged socioeconomic background and were more likely to smoke or have diabetes or high blood pressure.

"This finding highlights the importance of socioeconomic status in regard to higher distress and raises important questions about the role of race, sex and other factors," Garcia said.

The researchers plan to further investigate how socioeconomic and demographic factors may influence mental health among people who suffer a heart attack at a young age. Recent studies have suggested younger adults, especially women, account for an increasing proportion of the heart attacks occurring each year in the U.S., Garcia said, underscoring the importance of improving outcomes in this population.

"Outreach to the community has led to increased awareness of traditional heart disease risk factors and focus on things like diet and exercise, but many people, particularly younger people, may not be aware of the importance of mental health," Garcia said. "Our study offers a strong message to people recovering from a heart attack that ameliorating psychological distress is equally important."

Garcia cautioned that causation cannot be proven with an observational study and noted the possibility of recall bias among people with more severe disease, since psychological distress was self-reported in this study. While the study's sample size was relatively small, it did demonstrate a robust association using a prospective design.

It is now well known that carbon dioxide is the biggest contributor to climate change and originates primarily from burning of fossil fuels. While there are ongoing efforts around the world to end our dependence on fossil fuels as energy sources, the promise of green energy still lies in the future. Can something be done in the meantime to reduce the concentrations of CO2 in the atmosphere?

It would, in fact, be great if the CO2 in the atmosphere could simply be adsorbed! Turns out, this is exactly what direct air capture (DAC), or the capture of CO2 under ambient conditions, aims to do. However, no such material with the ability to adsorb CO2 efficiently under DAC conditions has so far been developed. "It is well known that CO2 is acidic in nature. Therefore, materials with basic nature are generally utilized as adsorbents for CO2. However, that often leads to corrosion of the system and is also not suitable for recycling the adsorbed CO2," explains Professor Yasushige Kuroda from Okayama University, Japan, who conducts research on surface chemistry.

Against this backdrop, in a recent study published in the Journal of Materials Chemistry A, scientists from Okayama University and Japan Synchrotron Radiation Research Institute (JASRI) led by Prof. Kuroda explored the adsorption properties of a material that has so far remained an "underdog": zeolites (minerals containing mainly aluminum and silicon oxides). "Zeolite materials have received little attention as adsorbents owing to their low CO2 adsorption capacity at room temperature and in the lower pressure adsorption region, as well as their poor selectivity over nitrogen," says Prof. Kuroda.

In their study, Prof. Kuroda and his team designed an ion-exchanging method of zeolite with alkaline-earth ions and achieved a remarkably high CO2 adsorption under ambient conditions. The team specifically chose an A-type zeolite (silicon/aluminum ratio of 1) because of its appropriate pore size for adsorbing CO2, while the alkaline-earth ion exchange imparted a large electric field strength that, supposedly, acted as a driving force for the adsorption. Scientists chose a doubly charged calcium ion (Ca2+) as the exchange ion since it allowed for the greatest amount of adsorption. In fact, the adsorbed volume noted was the largest amount of CO2 to have ever been adsorbed by any zeolite system, surpassing that for other materials under similar conditions!

To investigate the underlying adsorption mechanism, the scientists carried out far-infrared (far-IR) measurements and backed them up with density functional theory (DFT) calculations. The far-IR spectra, which detected the vibrational modes due to Ca2+-zeolite vibration, showed a distinct shift towards longer wavelengths following CO2 adsorption, a feature scientists could not recognize in other samples, e.g. Na-ion exchanged A-type zeolite. They further verified their observation with a model that showed good agreement with DFT calculations.

Moreover, the scientists were able to completely desorb the adsorbed CO2 and recover the original sample and its specific adsorption properties. In addition, the sample showed a superior selective adsorption of CO2 from other gases after the scientists examined the separation of CO2 using a model gas that emulated ambient air in its composition.

The findings thus bring zeolites to the forefront as an efficient adsorbent of CO2 under ambient conditions, a feat previously thought unachievable with these systems. "Our work can open doors to potentially novel applications of zeolites, such as in the cleaning of air inside semi-closed spaces including space shuttles, submarines, and concert halls, and as an adsorbent material in the anesthetic process," speculates Prof. Kuroda excitedly.

One thing is for sure, though: chemists will never look at zeolite in the same way again.

An article published in International Journal of Hyperthermia proposes a more effective protocol for the treatment of cardiac arrhythmias when applying radiofrequency energy at the site of the arrhythmia by catheterization. The research results from the final year project (TFG) on the bachelor's degree in Biomedical Engineering by Sergi Coderch Navarro, supervised by Ana González Suárez and Oscar Camara, researchers with the PhySense group of the BCN MedTech Research Unit at the UPF Department of Information and Communication Technologies (DTIC). Sergi Coderch Navarro defended his TFG in July 2019 and was a runner-up in the 2019 Gemma Rossell i Romero Awards. Currently, Ana González Suárez is a postdoctoral researcher at the Translational Medical Device Lab (University College Hospital Galway) within the National University of Ireland Galway.

Eliminating arrhythmias using radiofrequency energy

Cardiac ablation using radiofrequency energy is a minimally invasive procedure used for the elimination of arrhythmias. A catheter is inserted via a vein or an artery in the leg as far as the location of the arrhythmia in the heart. Then, energy is applied via the tip of a catheter so eliminate the arrhythmia just by heating the area. It is important to note that this kind of energy does not cause nerve or muscle stimulation.

During the intervention, clinical complications may arise due to excessive heating of the treatment area. There is no system in the clinical practice to predict or detect them

Although it is a minimally invasive treatment, during the intervention, clinical complications may arise due to excessive heating of the treatment area (exceeding temperatures of 100?C). Currently there is no system in the clinical practice to predict and detect these clinical complications and neither is the optimal protocol for the application of power known (i.e., appropriate power and time to apply the catheter to eliminate the arrhythmia) without causing excessive heating of the treated area.

Complications can be significant. One such complication is known as "steam pops", gas bubbles that form in the heart tissue causing the water in the tissue to turn into gas. These gaseous bubbles can burst, perforating the wall of the heart resulting in the death of the patient.

A mathematical model provides a new, more effective treatment protocol

Current protocols apply low power (20-30 W) over a long period (45-60 s), but a new energy application protocol has emerged recently called high-power in short-duration (HPSD), which applies very high powers (70-90 W) in a short time (4-7 s) to see if it is safer and more effective, i.e., whether it is able to minimize clinical complications while maintaining its effectiveness at eliminating the arrhythmia.

The new HPSD protocol is more effective than conventional ones currently used in the clinical practice to achieve shallower but extensive lesions

In his TFG, Coderch Navarro decided to build a three-dimensional mathematical model that simulates a commercial catheter used in the clinic in order to compare the safety and efficacy of conventional protocols with the new HPSD protocol. "The model has been solved numerically using the finite element method (FEM). The results of the simulations have been validated by experimental studies. Having validated the model, further simulations were carried out to evaluate situations that cannot be assessed (or are practically impossible to assess) experimentally, like for example, taking into account the different positions of the catheter on the tissue", Coderch Navarro explains.

And, the first author of the study adds: "The results suggest that the new HPSD protocol is more effective than the conventional ones currently used in the clinical practice to achieve shallower but extensive lesions, which are optimal for isolating the pulmonary veins and avoiding the risk of damage to the oesophagus".

The authors conclude that this study is a first step to guiding clinicians as to which is the most suitable protocol, depending on the position of the heart arrhythmia and the most appropriate orientation of the catheter. Although there is still a long way to go, this research has responded to one of the hot potatoes in the clinical practice of cardiac radiofrequency ablation.

The air in the United States and Western Europe is much cleaner than even a decade ago. Low-sulfur gasoline standards and regulations on power plants have successfully cut sulfate concentrations in the air, reducing the fine particulate matter that harms human health and cleaning up the environmental hazard of acid rain.

Despite these successes, sulfate levels in the atmosphere have declined more slowly than sulfur dioxide emissions, especially in wintertime. This unexpected phenomenon suggests sulfur dioxide emission reductions are less efficient than expected for cutting sulfate aerosols. A new study led by Tokyo Institute of Technology (Tokyo Tech), Hokkaido University and the University of Washington explains why.

The open-access paper was published on May 5 in Science Advances.

When concentrations of acidic sulfate from fossil fuel emissions decrease while the concentration of more basic ammonium molecules in the atmosphere stay constant, liquid water droplets in clouds become less acidic. This makes conversion of sulfur dioxide to sulfate more efficient. So, even though air quality regulations have reduced the supply of sulfur dioxide from power plants and shipping, the total amount of sulfate particulates that harm human health has dropped more slowly.

"This does not mean that the emissions reductions aren't working. It's just that there is a reaction which partially mitigates the reductions," said co-author Becky Alexander, a UW professor of atmospheric sciences. "We need to understand this multiphase chemistry in the atmosphere to design an efficient strategy to manage air pollution and accurately predict future air pollution and climate change impacts."

During most of the 20th century, sulfur dioxide emissions increased with industrialization in many parts of the world. But recently that trend has reversed in response to regulations, while ammonium emissions from animals and agriculture continue at the same rate. These trends are expected to continue.

Data from an ice core in Greenland that preserves past years' atmospheres show that the proportion of sulfate containing oxygen with one extra neutron, or oxygen-17, increased in the 1980s after countries began to regulate emissions. The authors' analysis shows this is due to faster sulfate formation in the liquid phase in the atmosphere, which occurs largely within clouds, under less-acidic conditions.

"After the SO2 emission control, relatively lower atmospheric acidity promotes the efficiency of sulfate production in the atmosphere, which weakens the response of sulfate level to the SO2 reduction," said lead author Shohei Hattori at Tokyo Tech. "Our unique isotopic techniques applied for the Greenland ice core records identify the key process of the weakened response of sulfate to SO2 emissions reduction."

The data came from an ice core drilled in southeast Greenland (SE-Dome) as part of a project led by Hokkaido University. The oxygen trapped in this ice provided evidence of sulfate composition from 1959 to 2015, without contamination from local pollution.

"Based on a continuous and high-resolution ice core record from SE-Dome, we could obtain reliable records for atmospheric aerosols without second modification after deposition," said co-author and leader of SE-Dome ice core project Yoshinori Iizuka at Hokkaido University. "We plan to drill a second ice core at the same location this year, and try to reconstruct the aerosol history back to the 1750s."

The ice core does not contain separate data for summer and winter, but models show that other, gas-phase chemical reactions for sulfur dioxide become more important in summer, reducing the summertime impact of changing cloud acidity. Knowing how these molecules react will help improve the atmospheric models used to forecast air quality and project climate change.

ORLANDO, May 5, 2021 - New research indicates that the legendary Sargasso Sea, which includes part of the Bermuda Triangle and has long featured in fiction as a place where ships go derelict, may actually be an important nursery habitat for young sea turtles.

In a study led by a University of Central Florida researcher and published today in the journal Proceedings of the Royal Society B, researchers presented evidence of baby green sea turtles arriving at the Sargasso Sea after entering the ocean off the east coast of Florida.

The study was the first time that green sea turtles have been tracked during their early "lost years," which is defined as the time between hatching from their nests along Florida's Atlantic coast and heading into the ocean and their "teenage years," when they return to coastal habitats after several years in the open ocean. Not much is known about where sea turtles go during these years, which is where the "lost years" description comes from. The new findings echo the team's previous research that showed baby loggerhead sea turtles arrive at the Sargasso Sea.

The results are helping to solve the mystery of where the turtles go and will also inform efforts to conserve the threatened animals, especially during their delicate first years at sea.

Florida's Atlantic coastline is a major nesting area for green and loggerhead sea turtles, which are iconic species in conservation efforts and important for their role in helping maintain ocean ecosystems, says UCF Biology Associate Professor Kate Mansfield, who led the study in collaboration with Jeanette Wyneken at Florida Atlantic University.

Scientists have long assumed that after hatching and going into the ocean, baby sea turtles would passively drift in sea currents, such as those circulating around the Atlantic Ocean, and ride those currents until their later juvenile years.

"That green turtles and loggerheads would continue in the currents, but that some might leave the currents and go into the Sargasso Sea was not ever considered or predicted by long-held hypotheses and the assumptions in the field," Mansfield says. "We found that the green turtles actively oriented to go into the Sargasso Sea and in even greater numbers than the loggerheads tracked in our earlier work. Granted, our sample sizes aren't huge, but enough turtles made this journey that it really throws into question our long-held beliefs about the early lives of sea turtles."

The Sargasso Sea, located off the east coast of the U.S. in the North Atlantic Ocean, has often been featured in popular culture, such as in Jules Verne’s Twenty Thousand Leagues under the Sea, as a place where ships could become derelict when trying to travel through thick mats of the floating, brown, Sargassum algae for which it is named.

The researchers were able to track the turtles by attaching advanced, solar-powered tracking devices, about an inch in length, to their shells. This also required determining the optimum adhesive for applying the sensor, which was different for the green sea turtles than for loggerheads because of the greens' waxier-feeling shells. The tracking device is designed to fall off after a few months and does not hurt the turtles or inhibit the turtles' shell growth or behavior, Mansfield says.

In the current study, 21 green sea turtles less than a year old, had transmitters affixed and were released into the Gulf Stream ocean currents about 10 miles offshore from the beach where they were born. The turtle release dates were from 2012 to 2013, and the researchers were able to track the turtles for up to 152 days.

Of the 21 turtles, 14 departed the Gulf Stream and the North Atlantic gyre of circulating currents and entered the western or northern Sargasso Sea region in the western Atlantic Ocean, according to the study. This is compared to seven out of 17 loggerhead turtles that left the Gulf Stream and entered the Sargasso Sea in the previous study.

Wyneken, a professor of biological sciences and director of Florida Atlantic University's Marine Science Laboratory at Gumbo Limbo Environmental Complex, worked with Mansfield to collect, raise, tag and release the turtles.

She says the research is important because it sheds light on where the baby turtles go during a delicate period in their lives.

"These studies in which we learn where little sea turtles go to start growing up are fundamental to sound sea turtle conservation," Wyneken says. "If we don't know where they are and what parts of the ocean are important to them, we are doing conservation blindfolded."

Jiangang Luo, PhD, a scientist with the Tarpon Bonefish Research Center at the University of Miami's Rosenstiel School of Marine and Atmospheric Science and study co-author, has a background in mathematical biology, oceanography and advanced scientific data visualization. As part of the research team, he helped process and analyze the data and graphed and animated the results.

"It feels great to see how the little turtles are traveling and utilizing the ocean," Luo says. "The ocean is our future, and we must have the ocean to save the sea turtles."

The Sargasso Sea Commission, which works as a steward for the area with support from multiple governments and collaborating partners, will use data from the research as part of its upcoming ecosystem diagnostic project, says the commission's Programme Manager Teresa Mackey.

The project will quantify threats and their potential impact on the Sargasso Sea, including climate change, plastics pollution and commercial activities, as well as investigate ways to counter challenges the area faces and establish a baseline for ongoing monitoring and adaptive management.

"Dr. Mansfield's research into the critical habitat that this area provides for turtles early in their life cycle gives concrete evidence of the importance of the Sargasso Sea for endangered and critically endangered species and is one of the many reasons why conservation of this high-seas ecosystem is vitally important for marine biodiversity," Mackey says.

UCF's Marine Turtle Research Group, which Mansfield directs, has been one of the commission's collaborators since 2017.

Mansfield says next steps for the "lost years" research will include looking more closely at differences in orientation and swimming behavior between turtle species, understanding the role Sargassum plays in early sea turtle development, and testing newer, smaller, and more accurate tracking devices to learn more about the places the baby turtles go and how they interact with their environment.

New observations and simulations show that jets of high-energy particles emitted from the central massive black hole in the brightest galaxy in galaxy clusters can be used to map the structure of invisible inter-cluster magnetic fields. These findings provide astronomers with a new tool for investigating previously unexplored aspects of clusters of galaxies.

As clusters of galaxies grow through collisions with surrounding matter, they create bow shocks and wakes in their dilute plasma. The plasma motion induced by these activities can drape intra-cluster magnetic layers, forming virtual walls of magnetic force. These magnetic layers, however, can only be observed indirectly when something interacts with them. Because it is simply difficult to identify such interactions, the nature of intra-cluster magnetic fields remains poorly understood. A new approach to map/characterize magnetic layers is highly desired.

An international team of astronomers including Haruka Sakemi, a graduate student at Kyushu University (now a research fellow at the National Astronomical Observatory of Japan - NAOJ), used the MeerKAT radio telescope located in the Northern Karoo desert of South Africa to observe a bright galaxy in the merging galaxy cluster Abell 3376 known as MRC 0600-399. Located more than 600 million light-years away in the direction of the constellation Columba, MRC 0600-399 is known to have unusual jet structures bent to 90-degree angles. Previous X-ray observations revealed that MRC 0600-399 is the core of a sub-cluster penetrating the main cluster of galaxies, indicating the presence of strong magnetic layers at the boundary between the main and sub-clusters. These features make MRC 0600-399 an ideal laboratory to investigate interactions between jets and strong magnetic layers.

The MeerKAT observations revealed unprecedented details of the jets, most strikingly, faint "double-scythe" structure extending in the opposite direction from the bend points and creating a "T" shape. These new details show that, like a stream of water hitting a pane of glass, this is a very chaotic collision. Dedicated computer simulations are required to explain the observed jet morphology and possible magnetic field configurations.

Takumi Ohmura, a graduate student at Kyushu University (now a research fellow at the University of Tokyo's Institute for Cosmic-Ray Research - ICRR), from the team performed simulations on NAOJ's supercomputer ATERUI II, the most powerful computer in the world dedicated to astronomical calculations. The simulations assumed an arch-like strong magnetic field, neglecting messy details like turbulence and the motion of the galaxy. This simple model provides a good match to the observations, indicating that the magnetic pattern used in the simulation reflects the actual magnetic field intensity and structure around MRC 0600-399. More importantly, it demonstrates that the simulations can successfully represent the underlying physics so that they can be used on other objects to characterize more complex magnetic field structures in clusters of galaxies. This provides astronomers with a new way to understand the magnetized Universe and a tool to analyze the higher-quality data from future radio observatories like the SKA (the Square Kilometre Array).

Coded messages in invisible ink sound like something only found in espionage books, but in real life, they can have important security purposes. Yet, they can be cracked if their encryption is predictable. Now, researchers reporting in ACS Applied Materials & Interfaces have printed complexly encoded data with normal ink and a carbon nanoparticle-based invisible ink, requiring both UV light and a computer that has been taught the code to reveal the correct messages.

Even as electronic records advance, paper is still a common way to preserve data. Invisible ink can hide classified economic, commercial or military information from prying eyes, but many popular inks contain toxic compounds or can be seen with predictable methods, such as light, heat or chemicals. Carbon nanoparticles, which have low toxicity, can be essentially invisible under ambient lighting but can create vibrant images when exposed to ultraviolet (UV) light - a modern take on invisible ink. In addition, advances in artificial intelligence (AI) models -- made by networks of processing algorithms that learn how to handle complex information -- can ensure that messages are only decipherable on properly trained computers. So, Weiwei Zhao, Kang Li, Jie Xu and colleagues wanted to train an AI model to identify and decrypt symbols printed in a fluorescent carbon nanoparticle ink, revealing hidden messages when exposed to UV light.

The researchers made carbon nanoparticles from citric acid and cysteine, which they diluted with water to create an invisible ink that appeared blue when exposed to UV light. The team loaded the solution into an ink cartridge and printed a series of simple symbols onto paper with an inkjet printer. Then, they taught an AI model, composed of multiple algorithms, to recognize symbols illuminated by UV light and decode them using a special codebook. Finally, they tested the AI model's ability to decode messages printed using a combination of both regular red ink and the UV fluorescent ink. With 100% accuracy, the AI model read the regular ink symbols as "STOP", but when a UV light was shown on the writing, the invisible ink illustrated the desired message "BEGIN". Because these algorithms can notice minute modifications in symbols, this approach has the potential to encrypt messages securely using hundreds of different unpredictable symbols, the researchers say.