Researchers from MIT have flown a plane powered by an ‘ion drive’ for the first time. The drive uses high powered electrodes to ionise and accelerate air particles, creating an ‘ionic wind’. This wind drove a 5m wide craft across a sports hall. Unlike the ion drives which have powered space craft for decades, this new drive uses air as its accelerant. The researchers say it could power silent drones.
Check out this video featuring Steven Barrett, the researcher who led the team:
This first flight made it about as far as the Wright brothers' first flight at Kitty Hawk. While it seems infeasible for passenger flights, it does have the potential to create a new class of small, silent, and clean drone aircraft.
In recent years, radio scientists have found a way to use the GPS constellation for purposes far beyond its intended use. The bounce-backs of GPS signals can be used to measure soil moisture, sea surface height, sea ice, wind velocities, and snow depth. After bouncing off of the Earth, the weak return signals are received by other satellites and contain information about the surface they hit. This process is called the Global Navigation Satellite System Reflectometry (GNSS-R).
Water reflects more microwave radiation than ice, causing stronger bounce-backs from melt regions. Researchers use this property to make maps of the reflectivity of the ice sheet during melt and non-melt seasons. Furthermore, the GPS signals can penetrate hundreds of feet into the ice, much deeper than existing measurements. As a result, the technique may be able to detect previously invisible subsurface melt, a new research area.
Spaceborne sensors are notorious for unplanned failures. The ability to make melt measurements from military-backed GPS satellites will provide a useful and more securely funded point of comparison for conventional measurements, potentially at greater subsurface depths than before.
Fire serves a vital role in our ecosystem. Forest managers often — also called a "controlled" burn — to mimic the natural fires in forests and grasslands that may stimulate , reveal in the soil, and increase seed vitality. Prescribed burns are performed by highly-trained individuals to in the ecosystem. Certain tree species like lodgepole pine, ponderosa pine, and the famous sequoia actually require fire to open their pinecones and release their seeds.
But do these burns help pollinators? A recent study from researchers at North Carolina State University examined the impact of prescribed burns on the native bee community in the Sandhills area of North Carolina. Bees are important insect pollinators of grasslands that depend on natural fire for ecological production. But fire destroys and removes flowering plants visited by bees. So how could fire help bees?
The study involved taking diversity counts — that is, placing traps to catch bees and identifying them at the species level — at sites that had been burned within two years and sites that hadn't been burned.
The researchers found there were 2.3 times more bees captured in more recently burned forest sites than in the unburned sites.
Researchers found there were more flowering plants at recently burned sites, increasing the diversity of flowers to benefit bees. Burns were conducted during the winter season, so as not to burn up that may serve as bee over-wintering habitat.
Forest ecosystems that require fire for growth are found across the country. Fire benefits forest and prairie ecosystems by stimulated tree growth and increasing the diversity and presence of native plants such as Echinacea, providing food sources for bee species. Prescribed burns are a powerful tool for land managers, and this study is one of a growing number aiming to show the benefits of prescribed burns for bees.
Anyone can be a science hero. Often, when we think of a science hero, a researcher, educator, doctor, nurse, or engineer comes to mind. But science heroes are also the individuals who aren't acknowledged in author lists on breakthrough papers, and are rarely highlighted in the media. In fact, some of these science heroes are the very same people who participate in clinical trials, willing to sacrifice everything for science, even after science has appeared to fail them.
A new study in the describes six such science heroes, known as “The Last Gift” cohort. The goal of this study was to enhance our understanding of HIV reservoirs, which refers to deep tissues where HIV hides even during treatment and remission. Fluids, like blood, transport HIV, where it is easily studied, but little is known about HIV in stationary reservoirs like the kidney, liver, and spleen.
Understanding HIV dynamics, both where it travels and where it hides, is important in order to develop therapeutic approaches, but currently, the ability to investigate HIV reservoirs is only possible after death. By the time tissues are normally collected, the virus has generally degraded and further study is useless.
This cohort consisted of six individuals with HIV, who were also diagnosed with a terminal illness from a non-HIV condition, such as cancer. As part of the cohort, they consented to not only blood sampling during their life, but also donated their bodies for rapid autopsy immediately after death. In this study, researchers conducting autopsies found HIV in every one of the 28 reservoirs they tested. This means that in order to completely eliminate HIV, researchers will need to target all of its hideouts in order to eliminate the virus.
The Last Gift is an extremely appropriate way to refer to these science heroes. Even with the knowledge that they had a fatal disease and would be unable to experience a more effective HIV treatment, they donated their bodies to science so that others might be able to benefit. It’s important to thank the thousands of science heroes who have and will make similar sacrifices, like The Last Gift cohort.
Imagine never having to charge your Fitbit or Apple Watch. How cool would that be? Except that it wouldn’t be, because the energy for charging your wearable device would come from your body heat (Ed: Ba-dum-tsh). This is exactly what a group of researchers from Northwestern University and Donghua University in China have achieved by creating the first ever working, wearable thermoelectric generators (TEGs). They recently published their findings in the journal Nature Communications.
Research on wearable TEGs has been underway for about a decade, although existing prototypes need to be perfected for practical use. Fundamentally, TEGs are made up of a conducting polymer, such as carbon nanotubes, and are able to convert absorbed heat into electric energy which then fuels battery power. But the currently available designs are too bulky to be integrated into fabric.
The scientists behind this new breakthrough generated TEG models using a special type of carbon nanotube fibers that's as thin and flexible as thread and could be woven into a fabric. Their TEGs have amazing stretch capabilities, capturing adequate thermal energy because they are aligned with the direction of heat flow from the body to the device. Lastly, their new TEG was able to transform this heat into battery power efficiently without being hampered by bodily movements. It showed a power density of 70 milliwatts per square meter for a 44 Kelvin temperature difference, one of the highest power outputs reported yet.
Tapping on keys, achieving steps and exercise goals all cause an increase in body heat. That day isn’t far when, the more we use our devices the more charged they will be. Until then, don’t forget your charging cords!
Occlusions are any kind of blocking off. If I step in front of you in line at the coffee shop, I have occluded you and also been a jerk. Go ahead, kick me in the shin.
This morning, the Moon is stepping in front of Mars. This occlusion, Mars-and-the-Moon, occurs twice a year. It's kind of like an eclipse, but an eclipse is a specific kind of occlusion where a shadow is cast. But here there's no shadow. Just Mars briefly hidden behind the Moon's back.
You'll be in the best position to see the end of the occlusion in the Pacific time zone. With a clear low view in the southeast, you'll see Mars pop back out from behind the Moon's back.
When we think of mosquitoes, we usually think of itchy bites and diseases like or . While they do feed on human and animal blood, mosquitoes are much like many other insects — they also use the sugar in nectar for energy for reproduction, movement, and survival.
A study by researchers at the University of Washington has — or unique scents that attract different pollinator species — that influence mosquito visitation to a flower. The lab found that a specific scent produced by Platanthera obtusata, the blunt-leaved bog orchid, attracts the Aedes mosquito. Scientists observed the feeding behavior of mosquitoes on orchid flowers, and analyzed the compounds of the orchid's scent using — a process which can identify chemical compounds based on the molecule's mass and chemical structure.
Mosquitoes feed on a wide variety of flowering plants, and in some cases even perform pollination while in search of nectar sources in the depths of flowers for sugar feeding.
The Platanthera orchids produced a distinct pattern of specific compounds, which are recognized and used by mosquitoes to distinguish between Platanthera and other species of orchids. The scent profile of Platanthera orchids and other mosquito-pollinated flowers were similar, taking science a step toward understanding why mosquitoes are more likely to pollinate one species over another.
By understanding the olfactory cues used by insects like mosquitoes, researchers can better understand the impact that smell has on the allure of mosquito prey, such as humans. Manipulation of mosquito senses serves a large role in mosquito bite prevention, and will play an important role in our future goal to eradicate mosquito-borne diseases.
You might have heard of iron deficiency anemia. Iron is the central element in hemoglobin, the oxygen-carrying protein of our blood. Having low concentrations of iron can lead to not having a proper circulation of oxygen, which usually translates to feeling tired or weak. However, there is also iron stored in tissues, including the brain. There, it helps with the cell’s production of energy, with the formation of myelin (i.e. white matter), and it is used by different enzymes that produce neurotransmitters.
Bart Larsen and their colleagues analyzed brain scans of 922 humans (8-26 years old). Using a technique called R2* relaxometry, they were able to quantify the concentration of iron in the brain by magnetic resonance. This concentration, especially in a brain region called basal ganglia increased over time in all samples. However, there were some observed sex differences, with women's brains reaching a peak of iron concentration earlier. By doing a battery of neurocognitive tests, the researchers found that there was a correlation between how much iron was being accumulated over time with a person's cognitive performance.
Although only a correlation, studies like this are important in finding how different external factors affect our development. Worth pointing out: iron deficiency is still a problem in the US affecting 15% of women and 3% of men. With this new study, we are more aware of the importance of iron in the normal brain development of teenagers.
Today is the . This day is celebrated each year, on the third Saturday of February, to raise awareness about pangolins. But this year, the ninth World Pangolin Day might have a different focus, given that a link has recently been suggested which originated in Wuhan, China. However, we cannot blame the spread of this coronavirus on the pangolin, even if they do turn out to be the carriers.
Pangolins are mammals ranging in size from about a foot to over three feet. There are eight species of pangolin in the world, all covered in scales made of keratin, the protein that also makes up our hair and nails. They eat insects, including ants and termites, which has earned them the name scaly anteater.
Sadly, pangolins face the risk of extinction in the wild, mainly caused by humans trafficking pangolins for their meat and their scales. In fact, they are among the most trafficked wild mammals in the world.
If pangolins do carry the SARS-CoV-2, which has not yet been conclusively proven, the spread was likely only possible due to this trafficking. Generally speaking, pangolins like to keep to themselves and are mostly nocturnal, so they do not often come into contact with humans naturally, unless we go out looking for them.
“I think that given the difficulty in monitoring the populations of all pangolin species, it is difficult to ascertain how well they are doing,” says Daniel Ingram, a researcher from the University of Stirling. The different species have different lifestyles — some live in trees, while others are ground-dwelling — which means that scientists need to develop different methods to monitor them.
“Understanding the behaviour of wild pangolins better could play a role in pangolin conservation, as it could help improve monitoring methods and help us understand how pangolins respond to human disturbances,” says Ingram.
And it seems like this is even more important if pangolins do turn out to be the SARS-CoV-2 carrier.
Jean-Paul Marat (1743-1793) was a French journalist, politician, physician, and scientist during the French Revolution, who was for his worsening skin condition. While the manner of Marat's death is obvious, the cause of his worsening health in his final years has remained a mystery, with doctors hypothesizing that conditions such as scabies, syphilis or atopic eczema may have been to blame. Now, to shed some light on this issue.
During his life, Marat was a French revolutionary who advocated for the rights of the sans-culottes (the poorest members of society), but also served as a court doctor, published findings on fire, electricity, and light, and wrote a regular periodical, titled (TheFriend of the People). At the time of his assassination, Marat was annotating two L'Ami du peuple issues in his bath. These blood-stained issues (made of old cellulose paper) were later donated to the Département des Estampes, Bibliothèque National de France, offering a rare opportunity for scientists to use DNA sequencing to posthumously diagnose infections in a historical figure.
In this study, Toni de-Dois and their fellow researchers took two non-destructive forensic swabs — one of a blood stain, and a second from an area of L'Ami du peuple with no blood stains for comparison. Following DNA extraction and sequencing, the researchers compared the two swab samples to account for any contamination that may have occurred in the last 200 years or so, before carrying out a number of analyses to better understand Marat's health at the time of his death.
Instead, researchers found DNA fragments matching Malassezia restricta, which is a fungal pathogen that causes seborrheic dermatitis (a chronic form of eczema). They also noted the presence of DNA fragments matching Cutibacterium acnes (although common, it is linked to acne) and Staphylococcus aureus (often detected in atopic dermatitis, though found in low quantities in Marat).
So what does this all mean?
Although de-Dois and their fellow researchers were unable to reach a specific diagnosis, they do provide evidence that Marat was suffering from an advanced fungal infection, likely seborrheic dermatitis, with additional bacterial infections. This study also happens to be one of the first to leverage DNA sequencing technology to diagnose infections in historical figures.
To find the exact answer to the mystery Marat's worsening health, researchers will need to analyze more of the DNA found on Marat's preserved possessions — with the potential to apply this analysis to additional historical figures.
We asked consortium members what they are reading, and wow, they really came through! Here are a few of the health-related books they recommend. Just so you know, Massive may collect a percentage of sales from the links on this page.
I think it goes without saying that I was drawn to the book because of the title. The book does a great job of explaining medical mishaps in an accessible and fun, but respectful, way. I can’t help but draw parallels between some of the historically-used remedies (e.g., wine enemas) and what some people do now (e.g., coffee enemas) - Monica Javidnia
In her essay collection, Esmé Wang describes her journey being diagnosed with bipolar disorder and subsequently after with schizoaffective disorder. I really enjoyed that the essays explored different aspects of the disease that I was unaware of such as involuntary hospitalization, mental illness stigma, and the history of the disease itself. While I was reading the essays, it became apparent how courageous the author is to share her life experiences and I think these essays will shed light on the disease and the stigma that surrounds it. - Felicia Davatolhagh
Inspired by her own difficult experience with getting a diagnosis of rheumatoid arthritis, Dusenbery presents a really compelling look at gender bias in medicine that left me frustrated with the status quo. She covers the origins and outcomes of this bias, including historical medical practices (ugh, “hysteria”), basic biomedical research, the inclusion (well, lack of) women and minority communities in clinical trials, and interactions with clinicians. I hope this inspires people in the biomedical community to do better. - Rachel Stewart
On January 31st, World Athletics released new technical rules officially qualifying what a 'legal' running shoe is. A host of brands, led by Nike with its Vaporfly series, have forced the hand of the regulatory agency by developing shoes containing new types of lightweight foam and shock-absorbing carbon plates that function like springs. These types of shoes have been proven in studies to improve running economy over conventional marathon racing shoes.
Because Nike has led the development of these shoes, their sponsored runners have enjoyed a relative advantage over their competitors dating back to the 2016 Olympic Trials, where 4th place finisher (Sketchers-sponsored) Kara Goucher compared the Vaporfly shoes to a doping advantage. Distance-running scientists weighed in on the resulting kerfuffle, proposing limits on sole height to future-proof the stacking of carbon plates resulting in bigger and bigger springs.
World Athletics modifies rules governing competition shoes for elite athletes.
It appears that World Athletics agrees: they've ruled that no more prototypes are allowed in competition; shoes must have a maximum sole height of 40 millimeters; and they may have no more than a single carbon plate. Those rules allow runners to wear Nike's popular Vaporfly 4% and Next% (pictured) shoes, but it appeared they would ban their Alphafly shoe, last year's prototype worn by both Eliud Kipchoge (1:59:40) and Brigid Kosgei (2:14:04) when they shattered record marathon times in Vienna and Chicago. However, upon official measurement the Alphafly just barely cleared the height limitation at 39.5 millimeters.
Shoe brands will continue to innovate with new materials and designs, but whether they manufacture exclusively within those limits from a commercial aspect remains to be seen: is there a market for shoes that may not be competition-legal, but that could allow amateur athletes to reach the performance levels of more gifted athletes? That is a question that science cannot answer.
The images of the Sun recently obtained by the Daniel K. Inouye Telescope are stunning, but you don’t need a 4.24-meter telescope to see the physics first-hand.
Plasma heats within the Sun, becomes less dense, then rises to the Sun's surface. Once there, it cools, gets dense, and sinks again. The gorgeous “caramel popcorn” appearance is a result of the plasma becoming ordered into cells the size of Texas. The edges of these cells are defined by dark lines of sinking plasma. This is described by Rayleigh-Benard convection, which tells how the size of these regions depend on the properties like the temperature, density, and viscosity of the plasma, and how heat transfers through it.
New research on the has generated a caffeine buzz in the news, but as a hipster, physicist, and a coffee snob, I feel obligated to contextualize these results.
As my fellow coffee lovers may know, espresso is made by forcing water through a bed of coffee particles, which extracts chemicals like caffeine and sugars. Smaller particles and higher pressures usually mean higher extraction and stronger cups, but experienced baristas know that grinding coffee finer doesn’t always produce a stronger cup. Baristas, but only now have scientists, in collaboration with the coffee community, succeeded in quantifying this effect.
With a mathematical model backed by experiments, researchers finally confirmed the theory that baristas have held for years; that high pressure (often achieved by adding more or finer grounds) and irregular particle size can cause flow channels to form, resulting in uneven wetting of the coffee, and ultimately making a weaker, less tasty brew.
Researchers hope this model helps make coffee more delicious with less waste — and the success of this work demonstrates the importance for clear science communication as fruitful collaborations can often be found outside academia.
Assessing the impacts of climate change is essential for scientists who want to understand ecosystem dynamics. However, until recently, relatively few studies have linked climate variability to species interactions.
Researchers used data from 22 years of sampling at the in Costa Rica to generate statistical models that measure changes in insect species diversity and richness and make future predictions. (Richness is a measurement of how many species are in a given area; diversity takes into account how many species there are as well as the number of individuals of each species.) Researchers looked at two types of insects: caterpillars and parasitoids. Parasitoids are a type of insect whose larvae live as parasites (usually in other insects) that eventually kill their hosts. These types of insects offer an important ecosystem service through species interactions by preventing outbreaks of herbivorous insects (like caterpillars) that can damage wild plant populations or crops in areas of agriculture.
The researchers found that species richness and diversity has declined in both caterpillars and parasitoids. Results suggest that these declines are partly driven by climate change and weather anomalies such as extreme precipitation and episodes of warmer than average temperatures, which have been occurring at an increasing rate at La Selva. Alongside the decreases in diversity and species richness, there has been a decrease in the interaction richness between caterpillars and parasitoids. A reduction in parasitism means that there is less biological control over herbivorous caterpillar outbreaks, which decreases ecosystem stability. By extrapolating the data for the next 100 years, this study predicts there will be a 30% drop in parasitism (compared to the 6.6% drop seen over the 22 year study period). These findings support the hypothesis that climate change is contributing to insect species declines. Further research is needed to explore the impacts of declining species interactions.
Playing a musical instrument requires a battery of unique skills, including being able to quickly and accurately assess incoming sounds, fine motor skills, and the coordination of behavior and feedback from one’s errors and mistakes. Receiving musical education at a young age has been shown to increase spatial-temporal skills. Musicians must often inhibit attention from one hand to focus on the movement of the other; this is called inhibitory control.
Inhibitory control is not a new idea; in fact, this concept is taught in most Psychology 101 lectures, using an example called the marshmallow test. In this famous experiment, an experimenter would place a marshmallow in front of a child and tell her to wait 15 minutes during the experimenter’s absence. The child was promised a second marshmallow if she had the willpower to wait. Those who waited and chose the delayed gratification tended to have better academic performance as adolescents.
A recent longitudinal study brings new light to this old topic. The results revealed children in their third year of musical training chose delayed gratification significantly more often than children in sports programs or those not participating in extracurricular activities. A previous study from the same research group showed that music students also had differences in brain activation (measured with fMRI) compared to students who were not involved in music or sports. During tasks that required cognitive control, the music students had increased activation of the inferior frontal gyrus (attentional demand and inhibition), anterior cingulate cortex (emotional control), and insula (self-awareness).
Scientists often conduct the first stage of drug trials in mouse models, including mice genetically engineered to develop Alzheimer’s disease. However, the accuracy of mice as a representation of human biology is being challenged daily, including by the authors of this in early January 2020.
Led by medical researchers at Washington University in St. Louis, the study shows that the most common Alzheimer’s disease (AD) mouse model, 5XFAD, has an entirely different genetic response to one of AD’s pathological hallmarks – . In AD, specific neuron proteins are broken into two fragments, called amyloid-beta 40 and 42. These fragments clump together into non-functional masses – the protein version of tumor cells – that form even larger plaques that destroy neuron connections and inhibit brain function.
However, when analyzing brain cells, like and , the mouse cells had entirely different genetic responses to amyloid-b than human cells. Certain genes and proteins were under-expressed in AD-mice microglia and over-expressed in AD-human microglia, compared to normal brains. In addition, astrocyte cell differentiation was only mildly affected by AD in mice, but severely mutated in AD-human brains, leading to the formation of 6 different types of impaired astrocytes.
The study is one of many contributing to the growing discussion of how accurate Alzheimer’s disease mouse models are and why, if they do not closely match to the human AD disease state, we should continue using them.
You may have heard of “” — insects that are infected with a fungal pathogen that can control their behavior, coercing them into climbing to a high location to better spread fungal spores before meeting their end. But did you know that another species of pathogenic fungus, Entomophthora muscae or “insect destroyer,” could be harnessed by humans to act as a Although we’ve known for decades that the insect destroyer fungus can infect flies, including the common housefly, we lacked the laboratory tools necessary to actually study the fungus-fly interaction in much detail.
Researchers at the University of California, Berkeley have that can infect the commonly-used fruit fly model organism, Drosophila melanogaster. This means that all of the tools we’ve accrued over the last century to study D. melanogaster in the lab can now be applied to its interaction with the fungus, making it much easier to learn how pathogens like the insect destroyer infect their host and control their behavior.
Scientists are also investigating the fungus itself, especially the ways that the fungus spreads its spores, which is a key part of how the fungus is able to infect new victims. Scientists found that E. muscae spores are shot out from cannon-like structures on the dead, infected flies at roughly 10m/s or 22mph — in the world of fungal spores. This even inspired a by biophysicists in Denmark that specifically examined the physics of spore ejection. The scientists created tiny, squishy cannons made of silicone that they could load with 3D-printed projectiles and fire with pressurized liquid, mimicking the actual ejection system used by the insect destroyer fungus. It turns out there’s a very specific canon and spore size that maximizes ejection speed and distance, increasing the chances of further fly infection.
The outbreak of a new coronavirus is a global public health emergency that has spread to at least 28 countries so far. There's a lot of news and it can be hard to make heads or tails of it all. It's a little overwhelming. Here are a few key updates that we think you should know about.
A diagnostic test has been authorized for use at public health labs across the U.S.
Until now, samples from suspected cases of the new coronavirus — dubbed "2019-nCoV acute respiratory disease” (where "n" stands for "novel" and "CoV" for "coronavirus") — had to be shipped to Centers for Disease Control and Prevention (CDC) labs. In an announcement on Tuesday, the Food and Drug Administration issued an emergency use authorization to fast-track the diagnostic test and permit its use at any CDC-qualified public health laboratory. The test itself converts specific regions of coronavirus's RNA genome into DNA, makes many copies of it using a process called amplification, and then tests it for the presence of these amplified bits with a glowing dye. Scientists hope that the availability of the test will prevent backlogs and enable the preventative measures that come with a real-time diagnosis.
Preprint repositories are spreading information, and misinformation
Preprint servers like bioRxiv have allowed scientists to share their research faster than ever before by giving papers a place to be read and shared before the peer review process. For perhaps the first time, we are now seeing how these repositories are helping and hurting in a public health response. Data sharing, through for forums like virological.org and the GISAID Initiative, have allowed researchers to sequence and start analyzing the coronavirus at unprecedented speed. At the same time, some scientists worry that publishing (and publicizing) before peer review is placing quantity over quality in this outbreak.
One preprint has already been withdrawn following widespread criticism, and bioRxiv has put up a banner on top of every page, cautioning viewers that the research posted there has not gone through peer review.
In one of my epidemiology classes this week, we split up into groups and underwent a coronavirus-themed crisis management case study. This is obviously just a simulation, but by day 21, the virus was everywhere and we had to transition from containment to mitigation.
I was struck by a recent article in STAT, which lays out two scenarios of what a future with endemic 2019-nCoV might look like:
One possibility adds this virus to the already four endemic human coronaviruses, which cause common cold and are a lower concern than something like the seasonal flu. Another possibility is a seasonal cycle in which coronavirus transmission dips during summer months due to their intolerance of higher heats and humidity.
We’ll keep checking in with these short roundups, so stay tuned.
Understanding and using quantitative information is important for animals to compete for resources, protect themselves from predators, get access to territories and for reproductive benefits. Certain species also exhibit an awareness of numerosity, or being able to , at fine scales. While humans rely on a symbolic sense of numerosity (we have symbols and names for counts), animals depend on Although they use this information for their survival, does this mean they are really counting?
Researchers from the lab of Giorgio Vallortigara have shown that in order to get to a “reward." Ordinal counting keeps track of a position (as in, the second door out of seven), as opposed to cardinal counting, which tracks an amount ("there are seven doors"). Zebrafish were trained to exit an arena with seven identical exits in a corridor, using only the second exit. This was done by blocking the other exits with a clear sheet of plastic. On the other side of the corridor was a reward of food and other fish. If the fish swam towards other exits, they did not receive any reward. But what happens when all doors are up for ‘swims’?
Post training, the fish were tested by decreasing the length of the corridor, decreasing the distance between exits, or increasing the number of exits. In the first two experiments, they chose the second exit with a frequency greater than random chance, indicating that they were in fact “counting” to choose which exit to use.
In the last experiment, along with choosing the second exit significantly more than the others, they also chose the second-to-last exit (second from the other end of the corridor) more than chance level. The higher numbers seemed to "confuse" the fish. In such contexts, the fish switched to using spatial feedback, along with ordinal information, to increase their chances of getting lunch with their pals.
Although evidence of numerical skills has been reported in , , and even , studying it in a well-established model system like zebrafish opens up avenues to decode the mechanisms underlying this behaviour.
What comes to mind when you hear the words particle accelerator?
Here's what I think, in the order of the thoughts that show up in my mind: giant metal ducts, Higgs boson, The Big Bang Theory and the CERN. I bet you got some of these as well (if not all of them), and here is why.
The Large Hadron Collider (LHC), at CERN in Geneva, is the very same particle accelerator where the Higgs boson was first observed. With a circumference of 27 kilometres, the LHC is the one of the largest machines in the world. It is even common knowledge as it has made headlines, and even been mentioned in The Big Bang Theory more than once.
However, did you know that approximately 30,000 particle accelerators exist today with many different functions? Not all of them are utilized for fundamental physics like the LHC — in fact only around 1% are. Instead, many of the smaller accelerators are used for cancer therapy, semiconductor manufacturing, or the production and identification of radioisotopes. In each case, the acceleration mechanism (which uses oscillating radio frequencies) requires large dimensions, coupled with high construction and maintenance costs, creating a limit on the use of such particle accelerators.
Instead, researchers in Europe are attempting to come up with a solution to bypass particle accelerators by using a plasma-based mechanism that should generate 1000 more acceleration potential per length.
Enter the European Plasma Research Accelerator with eXcellence, or for short.
EuPRAXIA plans to use the electric-field gradients, which are created in a pulse's wake, to accelerate particles to high energy levels while travelling over very short distances. It will require smaller, more compact and cost-effective machines.
Currently, plasma-based particle accelerators are still undergoing a proof-of-concept phase at multiple institutions, including CERN. If built, EuPRAXIA will be the world's first high energy plasma-based accelerator. In a recent conceptual design report, presented by over 40 institutes who are collaborating on this project, the authors state:
“EuPRAXIA is designed to be the required stepping stone to possible future plasma-based facilities… [it] should be fully functioning in the next 8-10 years.”
The idea is to build a facility — that also external operators could use — where the many intriguing potentials of particle accelerators will be explored, such that, maybe one day, giant metal ducts will not be the first thing that comes to mind.
After the "scare" near a Canadian nuclear power plant on January 12 which , many people are wondering about nuclear power. Is it safe?
In fact, nuclear power is one of the in terms of health burdens like air pollution. Even when you look at the larger picture of "death rate," nuclear energy is the — behind only hydroelectricity and wind. In fact, in one study, it was estimated that the use of nuclear power has . It has also been estimated, by the same study, that if nuclear power replaces fossil fuels, an additional .
And that's just the tip of the iceberg. Nuclear power is we have access to — while natural gas or coal power plants operate at full power , nuclear power plants operate at full power .
Now, many people are rightfully concerned about radiation (radioactivity is nothing to joke about). But, believe it or not, nuclear power plants release into the environment than coal power plants. That's right! In fact, the waste by-product produced by one coal power plant (known as fly ash), carries times more radioactivity into the environment than the shielded waste produced by a comparable nuclear power plant.
Now, of course, nuclear power isn't without its drawbacks — the problem of what to do with spent fuel is one of them, and past nuclear disasters may weigh heavily on people's minds. But to write off nuclear power as inherently unsafe or not worth pursuing, overlooks the many advantages it has when compared to coal burning, which has serious consequences in terms of air and water pollution as well as greenhouse gas emissions.
Being a fish in the Antarctic is hard. The bald notothen, a fish that hunts for prey under the ice in Antarctica, has come up with all kinds of tricks to be able to survive in the freezing waters. Like many fish that live in cold waters, the bald notothen has a kind of in its blood, which prevents it from freezing. However, this strategy comes at a cost. The antifreeze in combination with the cold temperature causes the blood to become viscous.
“Due to this increased blood viscosity, the heart must work much harder,” explains Jeroen Brijs, lead author of a . In the long term, this could cause significant problems for the fish, but they’ve come up with a solution: their spleens are able to take up red blood cells. This reduces the number of these cells in the blood, so the blood becomes less viscous.
But they need to use this technique carefully, because red blood cells are needed to transport oxygen, which the fish need to be active. Without the red blood cells, they are effectively anemic and unable to hunt or feed. The fish have solved this problem by using a dynamic strategy: they release the red blood cells when they need to be active, and take them up in times of rest. This tactic has made them extremely successful in the cold waters.
They are not the only fish that use this technique. “Although the blood boosting strategy of bald notothens is not unique within the notothenioids, the magnitude of the strategy in bald notothens is by far the greatest,” says Brijs. What the bald notothen does is effectively the same as blood doping in athletes, but the fish are much better at it. Athletes can only increase their oxygen carrying capacity by about 5-25 percent. The bald notothens can increase their ability to carry oxygen by as much as 207 percent.
In order to be successful in extreme environments, fish have evolved many strategies to survive and thrive. For many fish, blood doping might be the key to living in the cold seas.
The new coronavirus is scary, and lots of information is flying around in the pandemic. But please, don't believe everything you read, even if it came from scientists. Before panicking about news, wait for real, actual confirmation (and peer review) from scientists outside of a Twitter scrum.
Case in point, today a group of scientists based in India took the genome sequences of Wuhan coronavirus, did some armchair analysis (literally, all the work they did could be done from a desk in about an hour) which they shared in a pre-print (i.e. this hasn't gone through peer-review by other scientists yet), and found that it had similarities to the genome of...HIV.
Update, February 2nd: The paper has been withdrawn, following widespread criticism, like the kind below.
If you're a soup-brained Twitter user like me, you might have seen this sensational, zombie movie-ass tweet about the pre-print by Anand Ranganathan, a molecular biologist and author with 200k+ followers:
This prompted a blizzard of apocalyptic world building in the mentions, including a boost from prominent not-a-biologist New York Times opinion columnist Ross Douthat, who has about 160k followers:
The gist of the story is this: the Wuhan coronavirus (2019-nCoV) appears to have four additions to its genome that similar viruses, like SARS and MERS, are lacking. These additions are either identical or extremely similar to parts of the HIV genome. The authors go on to speculate that this may be why the coronavirus is spreading so quickly, and also that something sinister may be afoot:
"This uncanny similarity of novel inserts in [Wuhan coronavirus] to [HIV] is unlikely to be fortuitous."
They don't elaborate on what that means, but the Twitter interpretation is that someone engineered coronavirus with parts of HIV, to make it...I don't know. Infect better? It's unclear.
I double checked whether it was true that HIV and coronavirus have similarities. I took the four additional sequences (the "novel inserts") they found in the coronavirus genome and I looked to see if, as they said, it was similar to HIV. The truth is while these sequences do pop up in HIV, they also pop up in tons of other viruses. There's no reason to immediately suspect a nefarious fusion of HIV and coronavirus.
Sequence one out of four is indeed found in both Wuhan coronavirus and HIV. The same sequence also appears in a virus that infects Streptococcus (spherical bacteria), a rat virus, and an "acute bee paralysis virus."
I did the same analysis on sequence two. Once again, HIV and the Wuhan coronavirus appear together, but also a mouse herpes virus, a rat cytomegalovirus (the virus that causes mononucleosis, popularly known as mono or the 'kissing disease'), and a virus that infects sweet potatoes.
The stories for the other two sequences are the same. Those sequences appear in benign viruses like Peach-associated luteovirus (a plant virus), Bovine papillomavirus type 9 (the cow version of HPV), and Leptopilina boulardi Toti-like virus (a virus that infects wasps).
So the facts are that Wuhan coronavirus may have some new additions to it, but they're common bits and pieces found in tons of viruses — not just HIV — and there's no proof that they even have anything to do with how the Wuhan coronavirus behaves.
And there's definitely no proof that they were put there on purpose.
Microplastics have been making splashy headlines for years now and there's news: scientists used special carbon-containing polymers to track how microplastic moves through the aquatic biosphere. Plastics are very resistant to degradation in natural environments; knowing where they end up and how they're incorporated into food webs matters for human health. What starts out in algae can eventually end up in us.
To track how some microplastic moves through aquatic food webs, scientists in Finland and Austria turned to the molecular scale. They altered molecules of polyethelene (a common compound in plastics) to contain carbon-13, which they could use to trace those molecules later on. By measuring that tracer compound in the cell membranes of algae and zooplankton (aquatic microorganisms), they were able to see that carbon being incorporated into the organisms. As the zooplankton consumed the algae, the carbon went with them.
This is a step above how you might have seen plastic pollution before — a fish's stomach full of bits of bags and pieces of bottles. These microorganisms are actually repurposing the molecules in plastic, which increases the odds that other compounds in plastic could work their way up the food chain, too.
A future with quantum computers and quantum networks requires a diverse set of technical tools. Like the classical computers we use every day, we need physical platforms for memory, computation, and networking. Unlike classical computers, however, these platforms need to be quantum-mechanical (read: very small and very cold).
The verdict is still out on which physical platforms will work best for quantum computing, but scientists are making breakthroughs on the more promising ones. Just this year, coupled a single ion (charged atom) to a very strong light field for the first time. They achieved what atomic physicists call the “strong coupling regime,” where the ion is more likely to interact with the light field than to lose energy and information to the rest of its environment.
These physicists achieved the strong coupling regime by putting the trapped ion in an optical cavity: two mirrors facing each other that trap light for a number of round-trip reflections. The smaller the volume between these mirrors, the stronger the coupling between the light and the ion. By using optical fibers as mirrors, they were able to make this volume very small.
Light-ion coupling is exactly the sort of effect that will allow scientists to create quantum networks. To send quantum information between quantum computers, we can send photons with specific quantum states through optical fibers. However, optical fibers aren't perfect — photons lose information as they travel large distances.
By putting a strongly-coupled ion in an optical cavity at each of these nodes, we can transfer quantum states from an incoming photon to the ion and back to a new photon to send on its way. The advances in this paper increased the efficiency of an important step in this procedure () by a factor of 1,900 compared with previous iterations.
With a total efficiency of only 1.7%, however, there's still a lot of work to be done before the age of practical quantum networks.