Weight loss weightloss weight loss programs weight loss foods weight loss tips Giant extinct rodent was all brawn and little brain

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Artistic reconstruction of N. Acreensis (by Márcio L. Castro).

The now-extinct Neoepiblema acreensis (artist’s impression) is one of the largest rodents ever to have lived in South America, but its brain was minuscule for its size. Credit: J. D. Ferreira et al./Biol. Lett. (CC BY 4.0)

Palaeontology

A South American rodent had the heft of a Saint Bernard dog — and a brain the weight of a golf ball.

Behold Neoepiblema acreensis, an 80-kilogram rodent related to chinchillas that lived 10 million years ago in what is now Brazil. José Ferreira and Leonardo Kerber at the Federal University of Santa Maria in Brazil and their colleagues were curious about the brains of these beasts, so they used computerized tomography to peer inside two fossil skulls.

To compare brain sizes between creatures of varying weights, scientists can calculate a species’ ‘encephalization quotient’, a measurement of the difference between the expected brain size and actual brain size for an animal of a certain weight. Any value under 1 means an animal’s brain is smaller than expected.

The team estimates that the brain of N. acreensis weighed just 47 grams. The encephalization quotient of one individual studied was 0.20; that of the other individual was 0.33. In other words, N. acreensis’ brain was unusually puny in comparison to its body. By contrast, modern South American rodents have an average encephalization quotient above 1.05.

The researchers suggest that because N. acreensis had few predators to outwit, a large brain simply wasn’t worth the maintenance costs.

weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Suraka silk moth, Antherina suraka. Maroantsetra, northeast Madagascar.

The ‘fur’ on the body of the suraka silk moth (Antherina suraka) soaks up bats’ sonar signals. Credit: Alamy

Biophysics

Furry coating hides moths from echolocating bats.

Many moths sport luxurious pelts of scales, making them look like fuzzy butterflies. Thomas Neil and his colleagues at the University of Bristol, UK, wondered whether this fuzz functions as acoustic camouflage, concealing the moths from echolocating bats.

To find out, the team designed a loudspeaker and microphone system that simulated the echolocation apparatus used by nocturnal bats to detect prey. The researchers first beamed echolocation signals at specimens of two species of moth. They then used tweezers and a stiff paintbrush to de-fuzz the specimens, which were again pelted with sounds. The scientists found that moth fuzz absorbs, on average, 67% of incoming sound energy — a much better performance than commercially available sound insulation of similar structure and thickness.

Both moth scales and manufactured sound absorbers consist of parallel fibres with air trapped between them. Sound waves enter these air pockets and bounce around, causing the air molecules to vibrate and dissipate energy rather than bouncing back to the source.

Thanks to this acoustic camouflage, a bat must be 9–18% closer to moths to detect them than it would if the moths were smooth.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips New dinosaur-aged cavernicolous Mulleriblattina bowangi.

Dinosaurs’ neighbour: Mulleriblattina bowangi was a cockroach that dwelt in caves when giant reptiles roamed the Earth. Credit: H. Sendi et al./Gondwana Res.

Palaeontology

Insects showing adaptations to cavernous life scuttled the Earth 99 million years ago.

Two cockroach species that lived during the age of the dinosaurs are the earliest known animals to have been adapted for life in caves.

Specimens of the 99-million-year-old roaches are exquisitely preserved in amber from mines in Myanmar. Peter Vršanský at the Slovak Academy of Sciences in Bratislava and his colleagues named the species Mulleriblattina bowangi and Crenocticola svadba. Mulleriblattina has many of the typical features of its modern cave-dwelling relatives, such as small eyes and body size; Crenocticola might have been less specialized for cave life.

The new species are the only cave animals known from the Cretaceous Period, which lasted from 145 to 66 million years ago. The find suggests that many modern cave-living cockroaches in the family Nocticolidae, to which the new species belong, could have origins dating back 100 million years or more.

The authors say that some Cretaceous cave-living cockroaches might have fed on the guano of pterosaurs and dinosaurs, much as some cockroaches feed on the waste of birds and bats today. Cave-dwelling dinosaurs and pterosaurs might even have spread the insects from cave to cave.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Aerial photo of the Yongle Blue Hole (YBH) in the South China Sea.

A research platform floats above the Yongle blue hole, whose 130-metre-wide mouth is surrounded by coral reefs. Credit: P. Yao et al./JGR Biogeosciences

Ocean sciences

The Yongle marine cavern provides a window onto unusual ocean chemistry.

Carbon more than 8,000 years old lies deep inside a yawning sinkhole in the South China Sea.

Blue holes are underwater caverns carved into dissolving rock. The deepest known marine cavern is the Yongle blue hole, which measures roughly 300 metres from top to bottom. Its waters are mostly isolated from the surrounding ocean and receive little fresh water from rainfall, making it a rare spot to study the chemistry of oxygen-deprived marine ecosystems.

Peng Yao at the Ocean University of China in Qingdao and his team collected bottles of water at various intervals, from the Yongle’s mouth to a depth of 270 metres. The researchers found low levels of dissolved organic carbon and high levels of dissolved inorganic carbon, both of which are unusual for coastal waters. Radiocarbon dating showed that the deep dissolved carbon was thousands of years old, meaning that water in the depths of the hole had probably not mixed with the open ocean for a very long time.

The blue hole offers a rare glimpse of unusual ocean conditions, which may help scientists to understand the extreme chemistry of past and future oceans.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Background of the square ends of the wooden bars.

The petroleum-based adhesives used to make plywood could be replaced by a soya-based formula. Credit: Alamy

Organic chemistry

Chemists have borrowed a strategy from plant cell walls to produce a high-strength wood adhesive.

An element that props up plants’ cell walls can turn soya protein into a strong and eco-friendly glue.

The adhesives commonly used to bond wood into plywood and particleboard come from petroleum. But the earliest wood glues were made from proteins, such as soya flour. To make a comeback, soya adhesives must be made strong enough to meet building standards.

Jianzhang Li and his colleagues at Beijing Forestry University brought in boron, an element that provides essential support in plants’ cell walls. The researchers stirred soya protein into water, then added a pinch of borate salt and a dash of a large, branched molecule. The borate ions formed weak links with the hydrogen atoms on the branched molecules and those on soya protein’s long-chained molecules, linking them into a loose 3D mesh.

The authors used the soya-based adhesive to glue together sheets of veneer into plywood. When this plywood was pressed and heated, the borates’ weak bonds transformed into strong bonds, producing the same network structure found in plant cell walls.

The boron-containing adhesive was more than three times stronger than plain soya protein.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Methane bubbles frozen into the ice on the surface of a mountain lake.

Methane bubbles trapped in ice. Methane that has long been stored in frozen ground is unlikely to be released in sufficient amounts to accelerate climate change. Credit: Alamy

Climate change

Bubbles in Antarctic ice suggest that warming will not result in massive release of long-buried methane.

Runaway global warming driven by the release of methane from the Arctic seems less likely than some scientists have feared.

Methane and its components can be locked up for millennia in permafrost — a frozen mixture of soil and ice — and in deposits of crystal-like structures called methane hydrates. Methane released by modern organic materials contains a form of carbon that methane from ancient sources does not, allowing scientists to distinguish between the two types.

Michael Dyonisius at the University of Rochester in New York and his colleagues analysed Antarctic ice cores to determine the origins of methane released during a warming period that ended the last ice age. The warming raised global temperature by roughly 4ºC — slightly more than the rise projected to occur by 2100 in most scenarios of human-induced climate change.

The team’s results suggest that methane emissions during that big thaw were dominated by emissions from wetlands, not by the release of ancient methane from melting permafrost and methane hydrates. The authors conclude that modern climate change is unlikely to trigger a massive release of ancient methane.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Two visual representations of the same circular polymer conformation in simulation.

Researchers taught a neural network to recognize a type of knot called a 31, which can be modelled as a string of beads (left) or a string of rods (right). Credit: O. Vandans et al./Phys. Rev. E

Physics

After training, an artificial-intelligence program can distinguish between five types of knot with 99% accuracy.

Machine learning can tell different types of knot apart just by ‘looking’ at them.

For decades, mathematicians have had algorithms that calculate whether any two knots are of the same type — that is, whether the knots can be converted into each other without cutting the string. But these algorithms are slow: the number of steps they require grows exponentially with the complexity of the knots.

Liang Dai at the City University of Hong Kong and his collaborators created geometric models of the five simplest knots and fed those models into neural networks, which are computing systems modelled after the brain’s networks of neurons. After training on hundreds of thousands of such models, the networks had learnt to classify knots with 99% accuracy or better.

The technique is extremely fast, but it provides guesses with a high probability of correctness rather than certain answers. Moreover, it is unclear how it will perform as the knots grow in complexity. Still, the results show that machine learning could guide the study of knots, the authors say.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Caption: Variety of fresh green vegetables.

A species of bacterium in the human gut helps to bestow cancer-fighting abilities on members of the Brassica family such as broccoli and cabbage (seen here with other vegetables). Credit: Getty

Microbiome

Scientists reveal the pathway used by one gut microbe to transform vegetable components into anti-cancer compounds.

Broccoli — the poster child for vegetable hatred — has been rehabilitated recently thanks to its link to cancer prevention. Now researchers have revealed how a common gut microbe helps the body to take advantage of the health benefits of this and related foods.

Broccoli, cabbage, cauliflower and other vegetables in the Brassica genus owe their distinctive flavour to chemicals known as glucosinolates. During digestion, gut bacteria transform glucosinolates into compounds called isothiocyanates, which have protective effects against certain cancers.

Elizabeth Sattely at Stanford University in California and her colleagues pinpointed a set of genes that gives the gut microbe Bacteroides thetaiotaomicron the ability to turn glucosinolates into isothiocyanates. Mice colonized with B. thetaiotaomicron bacteria that lacked a complete set of these genes had lower levels of isothiocyanates in their digestive tract than did mice colonized with typical B. thetaiotaomicron. And when the researchers introduced the genes into bacteria that do not normally help to digest glucosinolates, the microbes began producing isothiocyanates.

Knowledge of this microbial mechanism could help efforts to engineer microbes to prevent and treat human disease, the authors say.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Detailed view showing how the rows of buried skeletons overlap.

Bodies lie in overlapping rows in a fourteenth-century grave for villagers killed by plague. Credit: Willmott/University of Sheffield/Antiquity Publications Ltd

Archaeology

The remains of at least 48 people who died of plague have been found at an unprecedented English site.

Archaeologists digging in the English countryside have discovered the first known Black Death mass grave in rural England — a sign of a community overwhelmed by the dead.

While excavating the grounds of Thornton Abbey in Lincolnshire, UK, Hugh Willmott at the University of Sheffield, UK, and his colleagues found a large collective burial site holding the remains of at least 48 people. Although epidemic-related mass graves had previously been documented in London, this was the first uncovered in rural England.

The bones date to the fourteenth century, a time period encompassing one of England’s major outbreaks of bubonic plague, also known as the Black Death. Analysis of DNA from the skeletons confirmed the presence of Yersinia pestis, the bacterium that causes plague. Christian burial rites were highly prized in medieval England, so the presence of a mass grave suggests the desperation of those spared by the epidemic.

Further genetic testing of the Y. pestis pathogen from the skeletons, the researchers say, could help to reconstruct the spread of the Black Death across the country.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Winter fight of two Striped Field Mice (Apodemus agrarius) in the snow. Moscow park, Russia.

There’s a word for it: male mice make specific ultrasonic sounds in the heat of battle. Credit: Getty

Animal behaviour

Male mice utter one type of high-pitched squeak when fighting, another when fleeing and yet another when pursuing a female.

For the first time, scientists have deciphered the ultrasonic squeaks that mice make during social behaviours such as chasing and fighting.

Mice emit a variety of sounds to communicate with others. But scientists have struggled to interpret these ultrasonic squeaks — imperceptible to the human ear — in part because of technical challenges in linking the sounds made by one mouse to the behaviour of another.

A team led by Joshua Neunuebel at the University of Delaware in Newark used machine-learning software called DeepSqueak to compare more than 111,000 individual vocalizations with more than 32,000 examples of various behaviours among mixed groups of male and female mice in a specialized recording chamber. Male mice tended to make distinct sounds depending on whether they were fighting, fleeing, chasing females or engaged in some other activity.

In many cases, a male’s squeaks were directed at another mouse. During chases, for instance, a dominant squeak from the chaser caused the mouse being chased — but not other mice in the chamber — to slow its pace.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Visualisation of quark structure of gold.

A gold atom’s nucleus (pictured, artist’s impression) has been observed executing an unusual type of spinning motion. Credit: ARSCIMED/SPL

Atomic and molecular physics

Scientists catch their first glimpse of an intricate type of nuclear movement.

For the first time, physicists have clearly observed a rare and complex motion of atomic nuclei called longitudinal wobbling.

An atomic nucleus is composed of protons and neutrons, collectively called nucleons. In an excited state, some nuclei with an odd number of nucleons exhibit a complex wobble — like that of a spinning top — because of their imbalanced geometry. Previous observations detected wobbling around only either the longest or shortest axis of nuclei having fewer than 170 nucleons.

Nirupama Sensharma at the University of Notre Dame in Indiana and her colleagues bombarded a ytterbium target with fluorine ions to produce the form, or isotope, of gold called gold-187. Analysis of gamma rays that the nuclei produced as they decayed indicated that the nuclei were wobbling. This makes 187Au the heaviest known wobbling isotope.

The team detected the 187Au nucleus wobbling about an axis that was neither its longest nor its shortest, but was of an intermediate length — the first clear observation of such behaviour.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips 3D reconstruction of whole adult human kidney imaged by the prototype light-sheet microscope.

A 3D reconstruction of a human kidney shows interior blood vessels (light green) and structures (purple) that filter waste products. Credit: S. Zhao et al./Cell

Biological techniques

Machine learning helps to expose the molecules and structures within a human kidney, eye and thyroid.

To study the body’s inner workings, scientists generally chop up organs and construct 3D images from several thin slices of tissue — a time-consuming and error-prone process. Now, researchers have developed a way to peer inside intact human organs in microscopic detail.

Ali Ertürk at the Munich Helmholtz Centre in Germany and his colleagues soaked organs in chemicals that preserve the structure of tissues while stripping them of fats and pigments that normally block the passage of light. The process makes tissues permeable to dyes and molecules that label specific structures, such as neurons and blood vessels.

To take 3D images of the clear organs, the researchers used a microscopy technique that helped them to image thin slices of tissue without having to cut into it. Then, the team developed machine-learning algorithms to rapidly analyse millions of individual cells in the images.

Using this approach, the researchers took detailed snapshots of an intact human eye, thyroid and kidney. The method could help to reveal human organ functions in health and disease, the researchers say.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips First example of a DNA origami nanomotor.

A beam-shaped DNA motor (grey) rolls swiftly along a straight path (black) with the help of DNA ‘legs’ (green) . Credit: A. Bazrafshan et al./Angew. Chem.

Nanoscience and technology

‘Origami’ nanomotors attain a blistering pace of 100 nanometres per minute.

In a one-of-a-kind race, DNA motors have achieved some of the fastest speeds and longest distances ever travelled by nanometre-scale machines.

The track: a standard glass slide covered with RNA. For the motors, Yonggang Ke, Khalid Salaita and their colleagues at Emory University in Atlanta, Georgia, folded a very long strand of DNA back on itself 16 times to create a 3D beam. The researchers attached 36 ‘legs’ — short RNA strands that could bind the RNA on the track — to each of the beam’s 4 long faces.

After the DNA devices were placed on the track, the legs on the bottom face found their footholds within minutes. To start the race, the researchers added an enzyme that breaks apart double-stranded RNA molecules. When the enzyme detached the legs from the track, each beam tipped forward onto its next face, thus rolling in a straight line from its starting point.

In a 99-vehicle race, some of the DNA motors sped down the track at more than 100 nanometres per minute, compared with only 10 nanometres per minute for previously developed DNA machines.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Food wastage.

As a nation becomes more wealthy, the amount of food wasted by its people grows. Credit: Alamy

Sustainability

New research explains why food waste is low in the Philippines but high in Belgium.

The world wastes twice as much food as previously estimated — and rich countries are disproportionately responsible

Markets allow harvested vegetables to rot; families throw out leftovers. These and other forms of loss and waste claim one-third of the world’s food supply, according to an estimate by the United Nations Food and Agricultural Organization (FAO).

Monika van den Bos Verma of Wageningen University and Research in The Hague, the Netherlands, and her colleagues wanted to explore how consumer affluence affects food waste. The researchers drew on 2003 data collected by the World Health Organization, the FAO and others to estimate calories purchased, calories consumed and calories wasted by people around the globe.

Belgium had the most food waste, and the Philippines had the least. (The study covered two-thirds of the world’s population, and did not include large food-wasting countries such as the United States.) As household spending rose above roughly US$6.70 per day per person, the amount of food waste also rose quickly, but then slowed.

Globally, people waste 527 calories per person per day — more than twice as much food as scientists had thought.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Stranded passengers in Manila after a storm.

Paddles replace pedestrians in Manila. Typhoons, known for dumping torrents of rain, can help to kick-start the dry season in the Philippines and nearby nations. Credit: Ted Aljibe/AFP/Getty

Climate sciences

Strong typhoons in the western Pacific Ocean funnel water vapour east — with effects on Asia’s populous island nations.

Despite their lashing winds and rains, strong typhoons in the western Pacific Ocean also help to cause the dry season in Southeast Asia.

Typhoons regularly unleash punishing rains on the Maritime Continent, the expanse of islands and sea that lies between the Indian and Pacific oceans and that includes the Philippines and Indonesia. Using more than 35 years of historical weather data, Enrico Scoccimarro at the Euro-Mediterranean Centre on Climate Change in Bologna, Italy, and his colleagues compared monthly measures of the strength of typhoons in the tropical western Pacific with precipitation over the Maritime Continent and the nearby ocean.

Compared with weak typhoons, stronger storms brought heavier precipitation over the ocean, but were associated with drier months in the Maritime Continent. This relationship held even after the team controlled for large-scale climate phenomena, such as El Niño.

The researchers’ computer simulations suggest that typhoons and dryness are linked because the storms carry atmospheric water vapour eastward, away from the landmasses. Improving typhoon forecasts, the authors say, could help to better predict the onset of Southeast Asia’s dry season.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips CRISPR-CAS9 gene editing complex.

The CRISPR–Cas9 enzyme complex (blue and grey) edits DNA (purple). Participants in one of the earliest clinical trials of a CRISPR-based therapy experienced no serious side effects. Credit: Ella Maru Studio/Science Photo Library

CRISPR-Cas9 genome editing

Immune cells whose genomes have been altered with CRISPR are well-tolerated by three people with cancer.

Preliminary results from one of the earliest clinical trials of CRISPR—Cas9 provide evidence that the technique is safe and feasible to use for treating human diseases.

‘Designer’ immune cells with enhanced abilities to seek and attack tumours have shown promise in treating some cancers. But researchers would like to improve methods to bolster immune cells’ cancer-fighting powers. One option is the use of CRISPR–Cas9, a method for making targeted changes to the genome.

Edward Stadtmauer and Carl June at the University of Pennsylvania in Philadelphia and their colleagues collected immune cells called T cells from three people with cancer. Using a conventional genetic-engineering method, the team gave the T cells the ability to recognize a protein produced by some cancer cells. The researchers also used CRISPR–Cas9 to block the T cells’ production of three proteins that might inhibit the cells’ ability to target tumours.

After being reintroduced into the trial participants’ bodies, the T cells thrived for at least 9 months without causing any significant side effects. However, cancer in all three participants has since continued to progress.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Teenager sleeping at desk in library.

Even teenagers who tend to wake up early benefit from starting school late in the day, according to a study of Argentine adolescents. Credit: Getty

Human behaviour

When lessons start at 7: 45 a.m., morning-loving students do better than those who naturally wake up later.

Whether they’re early birds or not, teenagers could get healthy amounts of sleep and improve their academic performance by attending school in the evening, according to a study of Argentinian adolescents.

Around the world, secondary school tends to start very early in the morning. But the biological clock ticking away inside many adolescent brains doesn’t align with school schedules, resulting in sleep loss and other problems.

María Juliana Leone at the National Council of Scientific and Technical Research in Buenos Aires and her colleagues collected sleep data from teenagers at a local secondary school at which students were randomly assigned to start classes at 7: 45 a.m., 12: 40 p.m. or 5: 20 p.m. The researchers placed students on a continuum from early-rising ‘larks’ to later-rising ‘owls’, according to their preferred waking time.

Analysis of students who started school in the morning showed that, compared with larks, owls had overall lower grades that worsened as they advanced through school. Almost no students on the morning schedule got adequate sleep, leading researchers to suggest that a progressive delay of school start times throughout adolescence could benefit all.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Two workers unload oranges from a truck at a weighing facility in the town of Axtla de Terrazas, San Luis Potosi, Mexico

Workers handle oranges in Axtla de Terrazas, Mexico. Mexican oranges sold in the United States can have a higher carbon footprint than oranges from more distant groves. Credit: Mauricio Palos/Bloomberg/Getty

Environmental sciences

Fruit hauled by container ship can prove more environmentally friendly than that carried shorter distances by road.

An analysis of oranges transported to market in four US cities shows that fruit imported from farms thousands of kilometres away can have a smaller carbon footprint than fruit that travels much shorter distances.

Eric Bell and Arpad Horvath at the University of California, Berkeley, looked at the ‘cradle-to-market’ greenhouse-gas emissions of oranges that travelled from agricultural regions, including those in California, Florida, Mexico and Chile, to four destinations: New York City; Los Angeles, California; Chicago, Illinois; and Atlanta, Georgia. The authors found that how an orange travels to market can be a bigger factor in the size of its carbon footprint than the distance it covers.

That’s because oranges freighted from afar are often transported by container ships and trains, which can carry much larger quantities than trucks and use much less fuel per kilo of oranges. For example, oranges that travel from Mexico to New York by truck have a travel-related carbon footprint six times larger than that of oranges that travel from Chile to New York by container ship, even though the distance from Chile is more than twice that from Mexico.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips An ion trap on a microchip with lasers shining on it.

An ion trap uses electric fields to hold a charged particle in place. Scientists used a similar device to immobilize a ytterbium ion before chilling it. Credit: Andrew Brookes, National Physics Laboratory/SPL

Atomic and molecular physics

A crowd of atoms helps to cool an ion to less than one ten-thousandth of a kelvin.

Researchers have cooled an ion in an ultra-cold gas until it moved so slowly that it exhibited quantum behaviour.

For decades, physicists have blasted materials with lasers to cool them to temperatures of just a fraction of a kelvin. Scientists have applied this technique to individual ions, which carry a charge, and to low-density gases consisting of uncharged atoms; both targets respond to chilling in ways predicted by the laws of quantum physics, which govern the Universe at very small scales.

To study how ultracold atoms and ions interact under quantum conditions, Rene Gerritsma at the University of Amsterdam and his colleagues used electric fields to trap a single ytterbium ion. They then placed the ion inside a cloud of several thousand lithium atoms that a laser had pre-cooled to just a few millionths of a kelvin. This cooled the ion to less than one ten-thousandth of a kelvin — slowing its thermal motion to a crawl.

Observations of the ion colliding with surrounding atoms revealed quantum effects, a first for an ion inside a cloud of neutral atoms.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Rhesus macaque, China.

A model projects that the rhesus macaque, which lives across Asia, harbours a large array of microbes that could infect people. Credit: Magnus Lundgren/Wild Wonders of China/NPL

Infection

Scientists identify two primate species as hosts of a high number of pathogens that can jump to Homo sapiens.

The mammals that are most likely to pass diseases to humans are those that easily share their bacteria and viruses across species boundaries.

Disease-causing microbes that have jumped from animals to humans include Ebola virus and the coronavirus behind the 2020 epidemic in China. Maya Wardeh at the University of Liverpool, UK, and her colleagues collected information on 1,560 mammalian species, including their geographical ranges, their interactions with humans and their pathogens. Using machine-learning software, the researchers organized the animals into a network that revealed how the species share 3,986 pathogens with one another.

Mammals that share pathogens with many other species are more likely to serve as reservoirs for human diseases, the researchers found. Among the species predicted to harbour the highest number of potential human pathogens are chimpanzees (Pan troglodytes), rhesus macaques (Macaca mulatta) and red foxes (Vulpes vulpes).

The researchers say that the findings could help to identify how bacteria, viruses and other infectious agents jump to humans.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Artistic reconstruction of N. Acreensis (by Márcio L. Castro).

The now-extinct Neoepiblema acreensis (artist’s impression) is one of the largest rodents ever to have lived in South America, but its brain was minuscule for its size. Credit: J. D. Ferreira et al./Biol. Lett. (CC BY 4.0)

Palaeontology

A South American rodent had the heft of a Saint Bernard dog — and a brain the weight of a golf ball.

Behold Neoepiblema acreensis, an 80-kilogram rodent related to chinchillas that lived 10 million years ago in what is now Brazil. José Ferreira and Leonardo Kerber at the Federal University of Santa Maria in Brazil and their colleagues were curious about the brains of these beasts, so they used computerized tomography to peer inside two fossil skulls.

To compare brain sizes between creatures of varying weights, scientists can calculate a species’ ‘encephalization quotient’, a measurement of the difference between the expected brain size and actual brain size for an animal of a certain weight. Any value under 1 means an animal’s brain is smaller than expected.

The team estimates that the brain of N. acreensis weighed just 47 grams. The encephalization quotient of one individual studied was 0.20; that of the other individual was 0.33. In other words, N. acreensis’ brain was unusually puny in comparison to its body. By contrast, modern South American rodents have an average encephalization quotient above 1.05.

The researchers suggest that because N. acreensis had few predators to outwit, a large brain simply wasn’t worth the maintenance costs.

weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Suraka silk moth, Antherina suraka. Maroantsetra, northeast Madagascar.

The ‘fur’ on the body of the suraka silk moth (Antherina suraka) soaks up bats’ sonar signals. Credit: Alamy

Biophysics

Furry coating hides moths from echolocating bats.

Many moths sport luxurious pelts of scales, making them look like fuzzy butterflies. Thomas Neil and his colleagues at the University of Bristol, UK, wondered whether this fuzz functions as acoustic camouflage, concealing the moths from echolocating bats.

To find out, the team designed a loudspeaker and microphone system that simulated the echolocation apparatus used by nocturnal bats to detect prey. The researchers first beamed echolocation signals at specimens of two species of moth. They then used tweezers and a stiff paintbrush to de-fuzz the specimens, which were again pelted with sounds. The scientists found that moth fuzz absorbs, on average, 67% of incoming sound energy — a much better performance than commercially available sound insulation of similar structure and thickness.

Both moth scales and manufactured sound absorbers consist of parallel fibres with air trapped between them. Sound waves enter these air pockets and bounce around, causing the air molecules to vibrate and dissipate energy rather than bouncing back to the source.

Thanks to this acoustic camouflage, a bat must be 9–18% closer to moths to detect them than it would if the moths were smooth.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips New dinosaur-aged cavernicolous Mulleriblattina bowangi.

Dinosaurs’ neighbour: Mulleriblattina bowangi was a cockroach that dwelt in caves when giant reptiles roamed the Earth. Credit: H. Sendi et al./Gondwana Res.

Palaeontology

Insects showing adaptations to cavernous life scuttled the Earth 99 million years ago.

Two cockroach species that lived during the age of the dinosaurs are the earliest known animals to have been adapted for life in caves.

Specimens of the 99-million-year-old roaches are exquisitely preserved in amber from mines in Myanmar. Peter Vršanský at the Slovak Academy of Sciences in Bratislava and his colleagues named the species Mulleriblattina bowangi and Crenocticola svadba. Mulleriblattina has many of the typical features of its modern cave-dwelling relatives, such as small eyes and body size; Crenocticola might have been less specialized for cave life.

The new species are the only cave animals known from the Cretaceous Period, which lasted from 145 to 66 million years ago. The find suggests that many modern cave-living cockroaches in the family Nocticolidae, to which the new species belong, could have origins dating back 100 million years or more.

The authors say that some Cretaceous cave-living cockroaches might have fed on the guano of pterosaurs and dinosaurs, much as some cockroaches feed on the waste of birds and bats today. Cave-dwelling dinosaurs and pterosaurs might even have spread the insects from cave to cave.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Aerial photo of the Yongle Blue Hole (YBH) in the South China Sea.

A research platform floats above the Yongle blue hole, whose 130-metre-wide mouth is surrounded by coral reefs. Credit: P. Yao et al./JGR Biogeosciences

Ocean sciences

The Yongle marine cavern provides a window onto unusual ocean chemistry.

Carbon more than 8,000 years old lies deep inside a yawning sinkhole in the South China Sea.

Blue holes are underwater caverns carved into dissolving rock. The deepest known marine cavern is the Yongle blue hole, which measures roughly 300 metres from top to bottom. Its waters are mostly isolated from the surrounding ocean and receive little fresh water from rainfall, making it a rare spot to study the chemistry of oxygen-deprived marine ecosystems.

Peng Yao at the Ocean University of China in Qingdao and his team collected bottles of water at various intervals, from the Yongle’s mouth to a depth of 270 metres. The researchers found low levels of dissolved organic carbon and high levels of dissolved inorganic carbon, both of which are unusual for coastal waters. Radiocarbon dating showed that the deep dissolved carbon was thousands of years old, meaning that water in the depths of the hole had probably not mixed with the open ocean for a very long time.

The blue hole offers a rare glimpse of unusual ocean conditions, which may help scientists to understand the extreme chemistry of past and future oceans.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Background of the square ends of the wooden bars.

The petroleum-based adhesives used to make plywood could be replaced by a soya-based formula. Credit: Alamy

Organic chemistry

Chemists have borrowed a strategy from plant cell walls to produce a high-strength wood adhesive.

An element that props up plants’ cell walls can turn soya protein into a strong and eco-friendly glue.

The adhesives commonly used to bond wood into plywood and particleboard come from petroleum. But the earliest wood glues were made from proteins, such as soya flour. To make a comeback, soya adhesives must be made strong enough to meet building standards.

Jianzhang Li and his colleagues at Beijing Forestry University brought in boron, an element that provides essential support in plants’ cell walls. The researchers stirred soya protein into water, then added a pinch of borate salt and a dash of a large, branched molecule. The borate ions formed weak links with the hydrogen atoms on the branched molecules and those on soya protein’s long-chained molecules, linking them into a loose 3D mesh.

The authors used the soya-based adhesive to glue together sheets of veneer into plywood. When this plywood was pressed and heated, the borates’ weak bonds transformed into strong bonds, producing the same network structure found in plant cell walls.

The boron-containing adhesive was more than three times stronger than plain soya protein.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Methane bubbles frozen into the ice on the surface of a mountain lake.

Methane bubbles trapped in ice. Methane that has long been stored in frozen ground is unlikely to be released in sufficient amounts to accelerate climate change. Credit: Alamy

Climate change

Bubbles in Antarctic ice suggest that warming will not result in massive release of long-buried methane.

Runaway global warming driven by the release of methane from the Arctic seems less likely than some scientists have feared.

Methane and its components can be locked up for millennia in permafrost — a frozen mixture of soil and ice — and in deposits of crystal-like structures called methane hydrates. Methane released by modern organic materials contains a form of carbon that methane from ancient sources does not, allowing scientists to distinguish between the two types.

Michael Dyonisius at the University of Rochester in New York and his colleagues analysed Antarctic ice cores to determine the origins of methane released during a warming period that ended the last ice age. The warming raised global temperature by roughly 4ºC — slightly more than the rise projected to occur by 2100 in most scenarios of human-induced climate change.

The team’s results suggest that methane emissions during that big thaw were dominated by emissions from wetlands, not by the release of ancient methane from melting permafrost and methane hydrates. The authors conclude that modern climate change is unlikely to trigger a massive release of ancient methane.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Two visual representations of the same circular polymer conformation in simulation.

Researchers taught a neural network to recognize a type of knot called a 31, which can be modelled as a string of beads (left) or a string of rods (right). Credit: O. Vandans et al./Phys. Rev. E

Physics

After training, an artificial-intelligence program can distinguish between five types of knot with 99% accuracy.

Machine learning can tell different types of knot apart just by ‘looking’ at them.

For decades, mathematicians have had algorithms that calculate whether any two knots are of the same type — that is, whether the knots can be converted into each other without cutting the string. But these algorithms are slow: the number of steps they require grows exponentially with the complexity of the knots.

Liang Dai at the City University of Hong Kong and his collaborators created geometric models of the five simplest knots and fed those models into neural networks, which are computing systems modelled after the brain’s networks of neurons. After training on hundreds of thousands of such models, the networks had learnt to classify knots with 99% accuracy or better.

The technique is extremely fast, but it provides guesses with a high probability of correctness rather than certain answers. Moreover, it is unclear how it will perform as the knots grow in complexity. Still, the results show that machine learning could guide the study of knots, the authors say.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Caption: Variety of fresh green vegetables.

A species of bacterium in the human gut helps to bestow cancer-fighting abilities on members of the Brassica family such as broccoli and cabbage (seen here with other vegetables). Credit: Getty

Microbiome

Scientists reveal the pathway used by one gut microbe to transform vegetable components into anti-cancer compounds.

Broccoli — the poster child for vegetable hatred — has been rehabilitated recently thanks to its link to cancer prevention. Now researchers have revealed how a common gut microbe helps the body to take advantage of the health benefits of this and related foods.

Broccoli, cabbage, cauliflower and other vegetables in the Brassica genus owe their distinctive flavour to chemicals known as glucosinolates. During digestion, gut bacteria transform glucosinolates into compounds called isothiocyanates, which have protective effects against certain cancers.

Elizabeth Sattely at Stanford University in California and her colleagues pinpointed a set of genes that gives the gut microbe Bacteroides thetaiotaomicron the ability to turn glucosinolates into isothiocyanates. Mice colonized with B. thetaiotaomicron bacteria that lacked a complete set of these genes had lower levels of isothiocyanates in their digestive tract than did mice colonized with typical B. thetaiotaomicron. And when the researchers introduced the genes into bacteria that do not normally help to digest glucosinolates, the microbes began producing isothiocyanates.

Knowledge of this microbial mechanism could help efforts to engineer microbes to prevent and treat human disease, the authors say.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Detailed view showing how the rows of buried skeletons overlap.

Bodies lie in overlapping rows in a fourteenth-century grave for villagers killed by plague. Credit: Willmott/University of Sheffield/Antiquity Publications Ltd

Archaeology

The remains of at least 48 people who died of plague have been found at an unprecedented English site.

Archaeologists digging in the English countryside have discovered the first known Black Death mass grave in rural England — a sign of a community overwhelmed by the dead.

While excavating the grounds of Thornton Abbey in Lincolnshire, UK, Hugh Willmott at the University of Sheffield, UK, and his colleagues found a large collective burial site holding the remains of at least 48 people. Although epidemic-related mass graves had previously been documented in London, this was the first uncovered in rural England.

The bones date to the fourteenth century, a time period encompassing one of England’s major outbreaks of bubonic plague, also known as the Black Death. Analysis of DNA from the skeletons confirmed the presence of Yersinia pestis, the bacterium that causes plague. Christian burial rites were highly prized in medieval England, so the presence of a mass grave suggests the desperation of those spared by the epidemic.

Further genetic testing of the Y. pestis pathogen from the skeletons, the researchers say, could help to reconstruct the spread of the Black Death across the country.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Winter fight of two Striped Field Mice (Apodemus agrarius) in the snow. Moscow park, Russia.

There’s a word for it: male mice make specific ultrasonic sounds in the heat of battle. Credit: Getty

Animal behaviour

Male mice utter one type of high-pitched squeak when fighting, another when fleeing and yet another when pursuing a female.

For the first time, scientists have deciphered the ultrasonic squeaks that mice make during social behaviours such as chasing and fighting.

Mice emit a variety of sounds to communicate with others. But scientists have struggled to interpret these ultrasonic squeaks — imperceptible to the human ear — in part because of technical challenges in linking the sounds made by one mouse to the behaviour of another.

A team led by Joshua Neunuebel at the University of Delaware in Newark used machine-learning software called DeepSqueak to compare more than 111,000 individual vocalizations with more than 32,000 examples of various behaviours among mixed groups of male and female mice in a specialized recording chamber. Male mice tended to make distinct sounds depending on whether they were fighting, fleeing, chasing females or engaged in some other activity.

In many cases, a male’s squeaks were directed at another mouse. During chases, for instance, a dominant squeak from the chaser caused the mouse being chased — but not other mice in the chamber — to slow its pace.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Visualisation of quark structure of gold.

A gold atom’s nucleus (pictured, artist’s impression) has been observed executing an unusual type of spinning motion. Credit: ARSCIMED/SPL

Atomic and molecular physics

Scientists catch their first glimpse of an intricate type of nuclear movement.

For the first time, physicists have clearly observed a rare and complex motion of atomic nuclei called longitudinal wobbling.

An atomic nucleus is composed of protons and neutrons, collectively called nucleons. In an excited state, some nuclei with an odd number of nucleons exhibit a complex wobble — like that of a spinning top — because of their imbalanced geometry. Previous observations detected wobbling around only either the longest or shortest axis of nuclei having fewer than 170 nucleons.

Nirupama Sensharma at the University of Notre Dame in Indiana and her colleagues bombarded a ytterbium target with fluorine ions to produce the form, or isotope, of gold called gold-187. Analysis of gamma rays that the nuclei produced as they decayed indicated that the nuclei were wobbling. This makes 187Au the heaviest known wobbling isotope.

The team detected the 187Au nucleus wobbling about an axis that was neither its longest nor its shortest, but was of an intermediate length — the first clear observation of such behaviour.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips 3D reconstruction of whole adult human kidney imaged by the prototype light-sheet microscope.

A 3D reconstruction of a human kidney shows interior blood vessels (light green) and structures (purple) that filter waste products. Credit: S. Zhao et al./Cell

Biological techniques

Machine learning helps to expose the molecules and structures within a human kidney, eye and thyroid.

To study the body’s inner workings, scientists generally chop up organs and construct 3D images from several thin slices of tissue — a time-consuming and error-prone process. Now, researchers have developed a way to peer inside intact human organs in microscopic detail.

Ali Ertürk at the Munich Helmholtz Centre in Germany and his colleagues soaked organs in chemicals that preserve the structure of tissues while stripping them of fats and pigments that normally block the passage of light. The process makes tissues permeable to dyes and molecules that label specific structures, such as neurons and blood vessels.

To take 3D images of the clear organs, the researchers used a microscopy technique that helped them to image thin slices of tissue without having to cut into it. Then, the team developed machine-learning algorithms to rapidly analyse millions of individual cells in the images.

Using this approach, the researchers took detailed snapshots of an intact human eye, thyroid and kidney. The method could help to reveal human organ functions in health and disease, the researchers say.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips First example of a DNA origami nanomotor.

A beam-shaped DNA motor (grey) rolls swiftly along a straight path (black) with the help of DNA ‘legs’ (green) . Credit: A. Bazrafshan et al./Angew. Chem.

Nanoscience and technology

‘Origami’ nanomotors attain a blistering pace of 100 nanometres per minute.

In a one-of-a-kind race, DNA motors have achieved some of the fastest speeds and longest distances ever travelled by nanometre-scale machines.

The track: a standard glass slide covered with RNA. For the motors, Yonggang Ke, Khalid Salaita and their colleagues at Emory University in Atlanta, Georgia, folded a very long strand of DNA back on itself 16 times to create a 3D beam. The researchers attached 36 ‘legs’ — short RNA strands that could bind the RNA on the track — to each of the beam’s 4 long faces.

After the DNA devices were placed on the track, the legs on the bottom face found their footholds within minutes. To start the race, the researchers added an enzyme that breaks apart double-stranded RNA molecules. When the enzyme detached the legs from the track, each beam tipped forward onto its next face, thus rolling in a straight line from its starting point.

In a 99-vehicle race, some of the DNA motors sped down the track at more than 100 nanometres per minute, compared with only 10 nanometres per minute for previously developed DNA machines.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Food wastage.

As a nation becomes more wealthy, the amount of food wasted by its people grows. Credit: Alamy

Sustainability

New research explains why food waste is low in the Philippines but high in Belgium.

The world wastes twice as much food as previously estimated — and rich countries are disproportionately responsible

Markets allow harvested vegetables to rot; families throw out leftovers. These and other forms of loss and waste claim one-third of the world’s food supply, according to an estimate by the United Nations Food and Agricultural Organization (FAO).

Monika van den Bos Verma of Wageningen University and Research in The Hague, the Netherlands, and her colleagues wanted to explore how consumer affluence affects food waste. The researchers drew on 2003 data collected by the World Health Organization, the FAO and others to estimate calories purchased, calories consumed and calories wasted by people around the globe.

Belgium had the most food waste, and the Philippines had the least. (The study covered two-thirds of the world’s population, and did not include large food-wasting countries such as the United States.) As household spending rose above roughly US$6.70 per day per person, the amount of food waste also rose quickly, but then slowed.

Globally, people waste 527 calories per person per day — more than twice as much food as scientists had thought.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Stranded passengers in Manila after a storm.

Paddles replace pedestrians in Manila. Typhoons, known for dumping torrents of rain, can help to kick-start the dry season in the Philippines and nearby nations. Credit: Ted Aljibe/AFP/Getty

Climate sciences

Strong typhoons in the western Pacific Ocean funnel water vapour east — with effects on Asia’s populous island nations.

Despite their lashing winds and rains, strong typhoons in the western Pacific Ocean also help to cause the dry season in Southeast Asia.

Typhoons regularly unleash punishing rains on the Maritime Continent, the expanse of islands and sea that lies between the Indian and Pacific oceans and that includes the Philippines and Indonesia. Using more than 35 years of historical weather data, Enrico Scoccimarro at the Euro-Mediterranean Centre on Climate Change in Bologna, Italy, and his colleagues compared monthly measures of the strength of typhoons in the tropical western Pacific with precipitation over the Maritime Continent and the nearby ocean.

Compared with weak typhoons, stronger storms brought heavier precipitation over the ocean, but were associated with drier months in the Maritime Continent. This relationship held even after the team controlled for large-scale climate phenomena, such as El Niño.

The researchers’ computer simulations suggest that typhoons and dryness are linked because the storms carry atmospheric water vapour eastward, away from the landmasses. Improving typhoon forecasts, the authors say, could help to better predict the onset of Southeast Asia’s dry season.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips CRISPR-CAS9 gene editing complex.

The CRISPR–Cas9 enzyme complex (blue and grey) edits DNA (purple). Participants in one of the earliest clinical trials of a CRISPR-based therapy experienced no serious side effects. Credit: Ella Maru Studio/Science Photo Library

CRISPR-Cas9 genome editing

Immune cells whose genomes have been altered with CRISPR are well-tolerated by three people with cancer.

Preliminary results from one of the earliest clinical trials of CRISPR—Cas9 provide evidence that the technique is safe and feasible to use for treating human diseases.

‘Designer’ immune cells with enhanced abilities to seek and attack tumours have shown promise in treating some cancers. But researchers would like to improve methods to bolster immune cells’ cancer-fighting powers. One option is the use of CRISPR–Cas9, a method for making targeted changes to the genome.

Edward Stadtmauer and Carl June at the University of Pennsylvania in Philadelphia and their colleagues collected immune cells called T cells from three people with cancer. Using a conventional genetic-engineering method, the team gave the T cells the ability to recognize a protein produced by some cancer cells. The researchers also used CRISPR–Cas9 to block the T cells’ production of three proteins that might inhibit the cells’ ability to target tumours.

After being reintroduced into the trial participants’ bodies, the T cells thrived for at least 9 months without causing any significant side effects. However, cancer in all three participants has since continued to progress.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Teenager sleeping at desk in library.

Even teenagers who tend to wake up early benefit from starting school late in the day, according to a study of Argentine adolescents. Credit: Getty

Human behaviour

When lessons start at 7: 45 a.m., morning-loving students do better than those who naturally wake up later.

Whether they’re early birds or not, teenagers could get healthy amounts of sleep and improve their academic performance by attending school in the evening, according to a study of Argentinian adolescents.

Around the world, secondary school tends to start very early in the morning. But the biological clock ticking away inside many adolescent brains doesn’t align with school schedules, resulting in sleep loss and other problems.

María Juliana Leone at the National Council of Scientific and Technical Research in Buenos Aires and her colleagues collected sleep data from teenagers at a local secondary school at which students were randomly assigned to start classes at 7: 45 a.m., 12: 40 p.m. or 5: 20 p.m. The researchers placed students on a continuum from early-rising ‘larks’ to later-rising ‘owls’, according to their preferred waking time.

Analysis of students who started school in the morning showed that, compared with larks, owls had overall lower grades that worsened as they advanced through school. Almost no students on the morning schedule got adequate sleep, leading researchers to suggest that a progressive delay of school start times throughout adolescence could benefit all.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Two workers unload oranges from a truck at a weighing facility in the town of Axtla de Terrazas, San Luis Potosi, Mexico

Workers handle oranges in Axtla de Terrazas, Mexico. Mexican oranges sold in the United States can have a higher carbon footprint than oranges from more distant groves. Credit: Mauricio Palos/Bloomberg/Getty

Environmental sciences

Fruit hauled by container ship can prove more environmentally friendly than that carried shorter distances by road.

An analysis of oranges transported to market in four US cities shows that fruit imported from farms thousands of kilometres away can have a smaller carbon footprint than fruit that travels much shorter distances.

Eric Bell and Arpad Horvath at the University of California, Berkeley, looked at the ‘cradle-to-market’ greenhouse-gas emissions of oranges that travelled from agricultural regions, including those in California, Florida, Mexico and Chile, to four destinations: New York City; Los Angeles, California; Chicago, Illinois; and Atlanta, Georgia. The authors found that how an orange travels to market can be a bigger factor in the size of its carbon footprint than the distance it covers.

That’s because oranges freighted from afar are often transported by container ships and trains, which can carry much larger quantities than trucks and use much less fuel per kilo of oranges. For example, oranges that travel from Mexico to New York by truck have a travel-related carbon footprint six times larger than that of oranges that travel from Chile to New York by container ship, even though the distance from Chile is more than twice that from Mexico.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips An ion trap on a microchip with lasers shining on it.

An ion trap uses electric fields to hold a charged particle in place. Scientists used a similar device to immobilize a ytterbium ion before chilling it. Credit: Andrew Brookes, National Physics Laboratory/SPL

Atomic and molecular physics

A crowd of atoms helps to cool an ion to less than one ten-thousandth of a kelvin.

Researchers have cooled an ion in an ultra-cold gas until it moved so slowly that it exhibited quantum behaviour.

For decades, physicists have blasted materials with lasers to cool them to temperatures of just a fraction of a kelvin. Scientists have applied this technique to individual ions, which carry a charge, and to low-density gases consisting of uncharged atoms; both targets respond to chilling in ways predicted by the laws of quantum physics, which govern the Universe at very small scales.

To study how ultracold atoms and ions interact under quantum conditions, Rene Gerritsma at the University of Amsterdam and his colleagues used electric fields to trap a single ytterbium ion. They then placed the ion inside a cloud of several thousand lithium atoms that a laser had pre-cooled to just a few millionths of a kelvin. This cooled the ion to less than one ten-thousandth of a kelvin — slowing its thermal motion to a crawl.

Observations of the ion colliding with surrounding atoms revealed quantum effects, a first for an ion inside a cloud of neutral atoms.

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weight loss  weightloss  weight loss programs  weight loss foods  weight loss tips Rhesus macaque, China.

A model projects that the rhesus macaque, which lives across Asia, harbours a large array of microbes that could infect people. Credit: Magnus Lundgren/Wild Wonders of China/NPL

Infection

Scientists identify two primate species as hosts of a high number of pathogens that can jump to Homo sapiens.

The mammals that are most likely to pass diseases to humans are those that easily share their bacteria and viruses across species boundaries.

Disease-causing microbes that have jumped from animals to humans include Ebola virus and the coronavirus behind the 2020 epidemic in China. Maya Wardeh at the University of Liverpool, UK, and her colleagues collected information on 1,560 mammalian species, including their geographical ranges, their interactions with humans and their pathogens. Using machine-learning software, the researchers organized the animals into a network that revealed how the species share 3,986 pathogens with one another.

Mammals that share pathogens with many other species are more likely to serve as reservoirs for human diseases, the researchers found. Among the species predicted to harbour the highest number of potential human pathogens are chimpanzees (Pan troglodytes), rhesus macaques (Macaca mulatta) and red foxes (Vulpes vulpes).

The researchers say that the findings could help to identify how bacteria, viruses and other infectious agents jump to humans.

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