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This latest image of Jupiter, taken by NASA's Hubble Space Telescope on Aug. 25, 2020, was captured when the planet was 406 million miles from Earth. Hubble's sharp view is giving researchers an updated weather report on the monster planet's turbulent atmosphere, including a remarkable new storm brewing, and a cousin of the famous Great Red Spot region gearing up to change color - again.

A unique and exciting detail of Hubble's snapshot appears at mid-northern latitudes as a bright, white, stretched-out storm traveling around the planet at 350 miles per hour (560 kilometers per hour). This single plume erupted on Aug. 18, 2020 - and ground-based observers have discovered two more that appeared later at the same latitude.

While it's common for storms to pop up in this region every six years or so, often with multiple storms at once, the timing of the Hubble observations is perfect for showing the structure in the wake of the disturbance, during the early stages of its evolution. Trailing behind the plume are small, rounded features with complex "red, white, and blue" colors in Hubble's ultraviolet, visible, and near-infrared light image. Such discrete features typically dissipate on Jupiter, leaving behind only changes in cloud colors and wind speeds, but a similar storm on Saturn led to a long-lasting vortex. The differences in the aftermaths of Jupiter and Saturn storms may be related to the contrasting water abundances in their atmospheres, since water vapor may govern the massive amount of stored-up energy that can be released by these storm eruptions.

Hubble shows that the Great Red Spot, rolling counterclockwise in the planet's southern hemisphere, is plowing into the clouds ahead of it, forming a cascade of white and beige ribbons. The Great Red Spot is currently an exceptionally rich red color, with its core and outermost band appearing deeper red.

Researchers say the Great Red Spot now measures about 9,800 miles across, big enough to swallow Earth. The super-storm is still shrinking as noted in telescopic observations dating back to 1930, but the reason for its dwindling size is a complete mystery.

Another feature researchers are noticing has changed is Oval BA, nicknamed by astronomers as Red Spot Jr., which appears just below the Great Red Spot in this image. For the past few years, Red Spot Jr. has been fading in color to its original shade of white after appearing red in 2006. However, now the core of this storm appears to be darkening slightly. This could hint that Red Spot Jr. is on its way to turning to a color more similar to its cousin once again.

Hubble's image shows that Jupiter is clearing out its higher altitude white clouds, especially along the planet's equator, where an orangish hydrocarbon smog wraps around it.

The icy moon Europa, thought to hold potential ingredients for life, is visible to the left of the gas giant.

This Hubble image is part of yearly maps of the entire planet taken as part of the Outer Planets Atmospheres Legacy program, or OPAL. The program provides annual Hubble global views of the outer planets to look for changes in their storms, winds, and clouds.

An early morning infrared image of Hurricane Teddy taken from NASA-NOAA's Suomi NPP satellite shows the proximity of the strengthening hurricane to the Lesser Antilles island chain and Puerto Rico. Teddy is a major hurricane on the Saffir-Simpson Hurricane Wind Scale.

NASA-NOAA's Suomi NPP satellite passed the North Atlantic Ocean overnight on Sept. 17 at 12:40 a.m. EDT (0440 UTC). The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a nighttime image of Hurricane Teddy. Puerto Rico and the Lesser Antilles can be seen lit up by night lights to the west in the image. The Lesser Antilles a group of islands that frame the eastern side of the Caribbean Sea.

The image was created using the NASA Worldview application at NASA's Goddard Space Flight Center in Greenbelt, Md.

By 11 a.m. EDT infrared imagery revealed Teddy's satellite appearance had steadily developed. There is now a ragged warming eye surrounded by a ring of convection with cloud tops colder than minus 76 degrees Fahrenheit/minus 60 degrees Celsius.

Teddy's Status on Sept. 17

At 11 a.m. EDT (1500 UTC), National Hurricane Center (NHC) said the center of Hurricane Teddy was located near latitude 19.3 degrees north and longitude 53.0 degrees west. Teddy was about 610 miles (980 km) east-northeast of the Lesser Antilles.

Teddy is moving toward the northwest near 12 mph (19 kph) and this motion is expected to continue for the next few days. Maximum sustained winds were near 120 mph (195 kph) with higher gusts.  Teddy is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. The estimated minimum central pressure is 957 millibars.

Teddy's Forecast

Some additional strengthening is possible through tonight as Teddy moves northwest. A slow weakening trend is expected to begin over the weekend.

This latest image of Jupiter, taken by the NASA/ESA Hubble Space Telescope on 25 August 2020, was captured when the planet was 653 million kilometres from Earth. Hubble's sharp view is giving researchers an updated weather report on the monster planet's turbulent atmosphere, including a remarkable new storm brewing, and a cousin of the Great Red Spot changing colour -- again. The new image also features Jupiter's icy moon Europa.

A unique and exciting detail of Hubble's new snapshot appears at mid-northern latitudes as a bright, white, stretched-out storm moving at 563 kilometres per hour. This single plume erupted on 18 August 2020 and another has since appeared.

While it's common for storms to pop up in this region, often several at once, this particular disturbance appears to have more structure behind it than observed in previous storms. Trailing behind the plume are small, counterclockwise dark clumps also not witnessed in the past. Researchers speculate this may be the beginning of a longer-lasting northern hemisphere spot, perhaps to rival the legendary Great Red Spot that dominates the southern hemisphere.

Hubble shows that the Great Red Spot, rolling counterclockwise in the planet's southern hemisphere, is ploughing into the clouds ahead of it, forming a cascade of white and beige ribbons. The Great Red Spot is currently an exceptionally rich red colour, with its core and outermost band appearing deeper red.

Researchers say the Great Red Spot now measures about 15 800 kilometres across, big enough to swallow the Earth. The super-storm is still shrinking, as noted in telescopic observations dating back to 1930, but its rate of shrinkage appears to have slowed. The reason for its dwindling size is a complete mystery.

Researchers are noticing that another feature has changed: the Oval BA, nicknamed by astronomers as Red Spot Jr., which appears just below the Great Red Spot in this image. For the past few years, Red Spot Jr. has been fading in colour to its original shade of white after appearing red in 2006. However, now the core of this storm appears to be darkening to a reddish hue. This could hint that Red Spot Jr. is on its way to reverting to a colour more similar to that of its cousin.

Hubble's image shows that Jupiter is clearing out its higher-altitude white clouds, especially along the planet's equator, which is enveloped in an orangish hydrocarbon smog.

Jupiter's icy moon Europa is visible to the left of the gas giant. Europa is already thought to harbour a liquid ocean beneath its icy crust, making this moon one of the main targets in the search for habitable worlds beyond Earth. In 2013 it was announced that the Hubble Space Telescope discovered water vapour erupting from the frigid surface of Europa, in one or more localised plumes near its south pole. ESA's JUpiter ICy moons Explorer, a mission planned for launch in 2022, aims to explore both Jupiter and three of its largest moons: Ganymede, Callisto, and Europa.

Hubble also captured a new multiwavelength observation in ultraviolet/visible/near-infrared light of Jupiter on 25 August 2020, which is giving researchers an entirely new view of the giant planet. Hubble's near infrared imaging, combined with ultraviolet views, provides a unique panchromatic look that offers insights into the altitude and distribution of the planet's haze and particles. This complements Hubble's visible-light picture that shows the ever-changing cloud patterns.

Reston, VA--A single-center observational study of more than 1,000 oncological examinations has demonstrated that positron emission tomography/magnetic resonance imaging (PET/MRI) facilitates cancer staging as well as PET/computed tomography (PET/CT) and improves lesion detectability in select cancers, potentially helping to promote fast, efficient local and whole-body staging in one step. The study, published in The Journal of Nuclear Medicine, also shows that PET/MRI significantly reduces overall radiation exposure when compared to PET/CT--of particular benefit to pediatric and adolescent patients.

While PET/CT is known as the diagnostic cornerstone in various oncologic imaging guidelines due to its sensitivity and high-resolution morphologic imaging, PET/MRI has higher soft-tissue contrast and lower radiation exposure. However, clinical data for PET/MRI are scarce due to the lack of clinical studies with relevant sample sizes.

In the observational study, a total of 1,003 whole-body PET/MRI examinations on 918 patients from a single center were compared with whole-body PET/CT examinations of the same patients. The oncological indications included lung cancer, gastrointestinal cancer or neuroendocrine cancer, gynecologic or breast cancer, prostate cancer, lymphoma, melanoma, head and neck cancer, cancer of unknown primary and malignant bone disease.

Board-certified nuclear medicine physicians and radiologists evaluated the examinations to identify additional findings on PET/MRI that were missing on PET/CT and probable diagnoses; additional but indeterminate findings on PET/MRI requiring additional examinations or follow-up; classification of indeterminate findings on PET/CT by PET/MRI; and missed findings on PET/MRI in comparison to PET/CT. Effective dose of both modalities was also investigated.

Additional information on PET/MRI was reported for 26.3 percent of examinations, compared with PET/CT. Of these, additional malignant findings were detected in 5.3 percent, leading to a change in TNM staging in 2.9 percent due to PET/MRI. Definite lesion classification of indeterminate PET/CT findings was possible in 11.1 percent with PET/MRI. In 2.9 percent, lesions detected on PET/CT were not visible on PET/MRI. Malignant lesions were missed in 1.2 percent on PET/MRI, leading to a change in TNM staging in 0.5 percent. The estimated mean effective dose for whole-body PET/CT amounted to 17.6 ± 8.7 mSv, in comparison to 3.6 ± 1.4 mSv for PET/MRI, resulting in a potential dose reduction of 79.6 percent.

"Due to the higher soft tissue contrast, PET/MRI improves lesion detection and reduces the need for additional examinations in comparison to PET/CT," said Benedikt Schaarschmidt, MD, professor and radiologist at the University Hospital Essen in Essen, Germany. "Especially in younger patients who need repeated diagnostic procedures, our data advocate the use of PET/MRI due to the markedly reduced radiation exposure of PET/MRI when compared to PET/CT."

He continued, "Hybrid imaging examinations are now part of complex diagnostic algorithms in multiple cancer types. Based on our data, PET/MRI could be an important adjunct to PET/CT by providing diagnostic advantages and improving diagnostic algorithms in numerous cancers at the same time. Furthermore, the markedly reduced radiation exposure of PET/MRI could lead to a more frequent use of this examination in oncological patients, most notably for treatment monitoring."

Consuming high fructose corn syrup appears to be as bad for your health as consuming sugar in the form of fructose alone, according to a new study from researchers at the University of California, Davis. The study reports health risks related to the type of sugar consumed, but also reveals novel risks when sugars are combined, which has important implications for dietary guidelines.

When it comes to health risks, sugar in the form of fructose is clearly the bad guy. This is because a majority of fructose consumed ends up in the liver. When there is too much fructose, the liver produces uric acid and fat in the form of triglycerides, which increase the risk of fatty liver, heart disease and gout. But lead investigator Kimber Stanhope, a researcher with the UC Davis School of Veterinary Medicine, says the new data shows that we shouldn't let glucose off the hook.

"It turns out that the combination of fructose and glucose found in high fructose corn syrup appears to be worse than fructose alone for some heart disease risk factors," said Stanhope. "When we planned this study, we didn't expect to find this."

Research has shown that fructose compared with glucose increases risk factors for heart disease and diabetes. This led to an assumption that the glucose in the high fructose corn syrup is benign. The new study, published in Metabolism Journal, tested this assumption by examining differences in health risk factors based on sugar type. Participants consumed beverages containing fructose, glucose, high fructose corn syrup, or an aspartame control, and researchers analyzed their blood for known risk factors for heart disease and diabetes.

The researchers expected risk factors would be highest for fructose and lowest for glucose, with high fructose corn syrup somewhere in between. This is exactly what they saw for some of the risk factors. However, for others, including the risk factors many scientists believe are the most predictive for heart disease, the increases were highest for high fructose corn syrup due to an interaction of fructose and glucose.

CONSUMER CHOICES AND DIETARY GUIDELINES

The results of the current study suggest that dietary guidelines and consumer choices should not be based on the assumption that all adverse effects from dietary sugars are due to fructose content.

"Our study shows that nutrition is more than looking at individual food components," said first author Bettina Hieronimus with the Department of Child Nutrition at the Max-Rubner Institut in Karlsruhe, Germany. "To understand the way our food affects our bodies, we need to study diets as a whole."

(Philadelphia, PA) - The COVID-19 pandemic has increasing numbers of doctors caring for patients virtually. While critical to protecting patient health during a pandemic, however, virtual care presents unique challenges, especially when it comes to diagnosis. Now, cardiologists at the Lewis Katz School of Medicine at Temple University (LKSOM), have come up with a virtual screening tool that greatly simplifies the process of diagnosing a complex form of heart failure known as pulmonary hypertension.

The new method--known as the virtual echocardiography screening tool (VEST)--makes use of initial screening data from echocardiography, which captures images of the heart. The ability of VEST to accurately and remotely diagnose pulmonary hypertension, based on simple analysis of multiple echocardiogram features, represents a major advance in virtual patient care.

"VEST enables physicians to quickly evaluate patients for pulmonary hypertension by simply searching for routine key measures indicated in echocardiogram reports," explained Anjali Vaidya, MD, FACC, FASE, FACP, Co-Director of the Pulmonary Hypertension, Right Heart Failure & CTEPH Program at Temple University Hospital, Associate Professor of Medicine at LKSOM and lead author on the new study. The report describing VEST was published online September 17 in the journal Pulmonary Circulation.

Pulmonary hypertension occurs when there is high pressure in the blood vessels connecting the right and left sides of the heart and can lead to right-sided heart failure. The condition typically is diagnosed based on right heart catheterization, which distinguishes specific types of the disease. Because patients with pulmonary hypertension are at high risk of serious illness if infected with COVID-19, due to pre-existing heart and lung disease, traveling to a Pulmonary Hypertension Center of Comprehensive Care or visiting a hospital to undergo invasive right heart catheterization for diagnosis is not as readily available as it had previously been. Most patients who are referred for invasive testing with right heart catheterization and evaluation previously have undergone echocardiography.

The new study shows that VEST is especially effective in distinguishing between the two most common, though very different, subtypes of pulmonary hypertension - the first caused by left heart disease, and the other by pulmonary arterial hypertension (PAH). Patients with pulmonary hypertension due to PAH frequently suffer poor survival. Delays in diagnosis (often up to 2-3 years) and treatment greatly impact these outcomes.

To evaluate the effectiveness and accuracy of VEST, Dr. Vaidya and colleagues analyzed data from patients with pulmonary hypertension who underwent right heart cardiac catheterization as well as echocardiography. To predict the subtype of pulmonary hypertension from echocardiography, the researchers looked at select reported echocardiogram features, including size and shape of the heart chamber and Doppler features. Scores derived from these measures were used to predict PAH versus pulmonary hypertension due to left heart disease.

"This is the first time that routine interpretation of echocardiogram reports, without direct advanced review of imaging, has proven to be effective," Dr. Vaidya said. "By using parameters routinely reported in echocardiograms to assess hemodynamic profiles, VEST truly facilitates the diagnosis of pulmonary hypertension."

"VEST makes early recognition of the condition possible, allowing patients to receive more timely referral for appropriate evaluation. The fact that this can be done remotely during virtual telemedicine visits is especially relevant in the COVID-19 era."

The next step for VEST centers on investigating its long-term impact on patient outcomes. "Now that we have a tool for assisting virtual diagnosis of pulmonary hypertension that any physician could use, we have a real opportunity to examine long-term outcomes in patients referred for treatment based on VEST findings," Dr. Vaidya added.

WOODS HOLE, Mass. -- Although it may seem counterintuitive, researchers are turning to an animal without a brain to crack the neural code underlying behavior.

Hydra vulgaris, a tiny, tentacled, freshwater organism, uses "nets" of neurons dispersed throughout its tube-like body to coordinate stretching, contracting, somersaulting, and feeding movements. This simple nervous system is one reason that Hydra is well suited for studying how electrical activity translates into motion.

In a study published in eNeuro, a duo from Columbia University and the Marine Biological Laboratory (MBL) has begun to crack the neural code behind Hydra's simplest behavior, called contraction bursts (when the torso shrinks down and expands outward, over and over again). The scientists found that the concentration of dissolved particles in the surrounding water -- a property known as osmolarity -- affects the activity of a neural circuit in one of Hydra's nerve nets, which can trigger a specific set of muscle cells to contract the torso.

"One by one, we want to decipher the neural and muscular activity behind each of Hydra's behaviors," says senior author and MBL Whitman Center Fellow, Rafael Yuste of Columbia University. "This paper is the beginning of our journey."

Yuste and first author Wataru Yamamoto conducted their experiments in Woods Hole during the summers of 2017 and 2018, in consultation with their MBL Hydra Lab research consortium. They used whole-body calcium imaging to visualize Hydra's neurons and muscles, and tested whether tweaking various environmental conditions such as water temperature, body size, nutritional state, and osmolarity would affect contractions. They were surprised to find that just one of those parameters, osmolarity, had an impact.

Boosting the concentration of sugar particles in the water triggered fewer contractions and decreased activity in the "contraction burst" (CB) neural circuit as well as in one set of muscles. Lowering particle concentration had the opposite effect, increasing cellular activity and contractions. Although additional experiments are needed to confirm their theory, the researchers propose that CB neurons respond to changes in osmolarity by altering muscle activity, which in turn influences contraction frequency.

Reacting to changes in particle concentration could mean the difference between life and death for Hydra -- especially if salt is involved. As freshwater dwellers lacking advanced excretory systems, Hydra are not well-equipped to maintain the proper balance of salinity inside and outside their bodies. Water is constantly flowing in and out of their gastrovascular cavities, and too much internal salty solution causes them to balloon and literally explode. The researchers surmise that Hydra contract in response to high osmolarity to "wring" themselves out and expel excess water.

In addition to affecting contractions, osmolarity also influenced how often Hydra detached and repositioned its tube foot, likely preparing to move to a new location. Yamamoto plans to continue to investigate how and why this happens. He hopes his line of inquiry will eventually help decode a more complex behavior: somersaulting, when Hydra flips tentacles-over-tube foot, like a circus acrobat.

Researchers from Oregon Health & Science University and the VA Portland Health Care System conducted in-depth interviews with patients at the VA and came up with a series of six recommendations to reduce the number of times patients miss appointments.

The study is published in the Journal of General Internal Medicine.

"No-shows are a big deal because they are a really preventable source of inefficiency in the health care system," said lead author Alan Teo, M.D., M.S., associate professor of psychiatry in the OHSU School of Medicine and a researcher and psychiatrist at the VA. "Previous research suggests that patients who miss visits are at a higher risk of negative health outcomes, so this is an important population of patients to be thinking about and taking better care of."

From an economic standpoint, missed appointments set off a cascade of costs in the health care system, through the ripple effect created by patients, clinicians and medical assistants in rescheduling.

Previous research led by Teo indicated that directly connecting by telephone with an advance reminder reduces no-shows considerably. The new research expands on that finding through a series of systematic interviews conducted with 27 patients seen at the VA in Portland.

Based on that feedback, researchers developed six key recommendations for appointment reminders, underscored by illustrative quotes from patients:

Mix it up. Varied content and format signal patients to examine reminders more closely. "When I see something different, I usually at least read it once. But if it's the same every time, I don't."

Add a personal touch. Many patients would like communications to be more personable and for the appointment systems to be more human. "You're human, I'm human. Let's interact."

Include clinic specifics. Reminders could be improved by including key location and contact information such as a map, the precise location of a clinic and a direct phone extension for the clinic.

Keep it short and simple. Appointment reminders that are short, simple and direct are preferred. "In a letter, short sweet and to the point. I think less is more in that situation."

Time reminders based on the mode of delivery. Appointment letters and postcards should be delivered about a week in advance, while text message reminders are best-suited to one or two days prior.

Hand over reminder control to the patient. Patients have varied preferences and needs when it comes to appointment reminders. They would like to have a say in the types of reminders they receive, such as through a clear opt-out or opt-in system. "I wish I could opt out of the letter. Because I think it's a waste of paper, personally, for me. Paper, postage, for the government to spend, when I prefer electronic."

The vast majority of Twitter users who vape with JUUL e-cigarettes are not using the devices to stop smoking or to improve their health, according to a research team led by University of Utah Health scientists. The researchers say this finding, which challenges JUUL's stated mission of improving smokers' lives, could help hone anti-smoking and vaping efforts targeted at Twitter users, particularly underage teens.

Based on their manual analysis of more than 4,000 tweets, the scientists concluded that only 1% of Twitter users mentioned JUUL as a smoking cessation method and scarcely 7% referred to any potential health benefits of using the vaping devices.

The study, which was conducted in conjunction with the University of Washington School of Medicine and the University of California, San Diego, appears in the Journal of Medical Internet Research - Public Health & Surveillance.

"Some people thought that my generation was going to end smoking," says Ryzen Benson, lead author of the study and a graduate student in the U of U Health Department of Biomedical Informatics. "For a while, we did see a large decline in smoking among teens and younger adults. But then JUUL and other electronic nicotine delivery systems became popular."

"This emergence is reflected in what we found being posted on Twitter," Benson says. "Based on what we saw in people's tweets, they are clearly not using JUUL as a smoking cessation tool or as a healthier alternative to traditional cigarettes."

Use of e-cigarettes--devices that heat liquid to produce a vapor that users inhale into their lungs--has skyrocketed since they were first introduced in 2007. Between 2017 and 2019, the percentage of high school students who vape rose almost 2.5 times, from 11.7% to 27.5%, according to the Centers for Disease Control. In 2020, that percentage has dipped to about 20%, perhaps due in part to vaping being linked to more than 2,500 hospitalizations nationwide--and 55 deaths, including one in Utah--before the end of 2019. 

Previous studies have suggested that social media, including Twitter, could be driving the popularity of e-cigarette usage as well as providing a forum for misinformation about the risks of using these devices. Intrigued, the researchers involved in the current study sought to find out what Twitter users, particularly teens, are posting about JUUL, the most popular e-cigarette brand, which accounts for 76% of the vaping market. 

Using vaping-related keywords such as "JUUL," "vaping pod," and "pod mod," the researchers accessed a free Twitter application that allowed them to collect 29,590 relevant tweets posted nationwide from July 2018 to August 2019. After eliminating duplicates, they used both manual and computational machine learning techniques to analyze the remaining 11,556 unique English language tweets.

Of the 4,000 tweets that were manually analyzed, the researchers found that 3,152 (79%) specifically mentioned JUUL or JUUL-related products and accessories. Of these, 1,792 (57%) referred to first-person usage such as, "I left my JUUL at the party last night." Overall sentiment was more positive ("I love JUUL") than negative ("I will never touch JUUL again!"). Only 45 tweets (1%) mentioned JUUL as a means of smoking cessation; 216 (7%) referred to possible health benefits or concerns.

"I was expecting that few tweets would mention smoking cessation but wasn't expecting only 1%", says Mike Conway, Ph.D., senior author of the study and assistant professor of biomedical informatics at U of U Health. "I was also expecting there to be more discussion of health-related issues, which turned out to be largely absent from our dataset."

The researchers manually identified more than 200 tweets that likely were from underage users ("For my 16th birthday, I want mango JUUL pods"). They then used machine-learning algorithms to see if computers could identify these underage tweets faster and more accurately among 7,356 tweets that were not manually analyzed. They did.

"By developing machine-learning algorithms, we can identify underage tweets with 99% accuracy in just minutes or even seconds," Benson says 

The study only analyzed a small number of the total available tweets stored on Twitter. The keyword list was not exhaustive and didn't include all e-cigarette devices used in the United States. The researchers also note that Twitter users may not be representative of the general U.S. population.

Moving forward, the researchers hope this information can be used to generate   tailored health messages. The messages, based on keywords that appear in social media exchanges, could be automatically delivered to JUUL users who use Twitter and other sites, Conway says.

Below please find a summary and link(s) of new coronavirus-related content published today in Annals of Internal Medicine. The summary below is not intended to substitute for the full article as a source of information. A collection of coronavirus-related content is free to the public at http://go.annals.org/coronavirus.

1. Social distance proves key as respiratory route found to be the most common way to spread COVID-19

COVID-19 is spread most often through respiratory droplets or aerosols and little evidence exists supporting transmission through surfaces. As such, social distance and proper ventilation are key determinants of transmission risk. Findings from a review of published research, articles, and reports is published in Annals of Internal Medicine.

Researchers from Montefiore Medical Center, Hospital of the University of Pennsylvania, Massachusetts General Hospital, Harvard Medical School, and Brigham and Women's Hospital studied scientific articles published between January and September 2020, as well as relevant articles and institutional or governmental reports, to determine the viral, host, and environmental factors that contribute to transmission of COVID-19. They found that although several experimental studies suggest that virus particles could live for hours after inoculation in aerosols or on surfaces, the real-world studies that detect viral RNA in the environment report very low levels on surfaces, and few have isolated viable virus. Strong evidence from case and cluster reports indicates that respiratory transmission is dominant, with proximity and ventilation being key determinants of transmission risk. In the few cases where direct contact or transmission from materials or surfaces was presumed, respiratory transmission could still not be ruled out.

The researchers also identified patterns in virus transmission. The evidence showed that COVID-19 virus peaks around a day before symptom onset and declines within a week of symptom onset. All transmissions occur early on and none have ever been documented after a patient has had symptoms for about a week. Most persons do not transmit the virus, whereas some cause many secondary cases in transmission clusters called "superspreading events." According to the authors, their findings should help to inform evidence-based policies and practices to help educate the public and slow the spread of this virus. Read the full text: https://www.acpjournals.org/doi/10.7326/M20-5008.

Media contacts: A PDF for this article is not yet available. Please click the link to read full text. Author Eric A. Meyerowitz, MD can be reached through Elaine Landoli at elaine.iandoli@einsteinmed.org and author Aaron Richterman, MD can be reached through Alex Gardner at alex.gardner@pennmedicine.upenn.edu.

2. Novel, rapidly deployable community isolation quarantine facilities help to manage COVID-19

A substantial proportion of stable patients with COVID-19 can be isolated safely outside a hospital setting with a small health care team. Researchers from Singapore General Hospital discuss how isolation facilities can be created rapidly to care for patients without serious adverse outcomes. An article describing their process and outcomes is published in Annals of Internal Medicine.

Singapore is one of the most densely populated small island-states in the world. During the COVID-19 pandemic, Singapore implemented large-scale institutional isolation units called Community Care Facilities (CCFs) to combat the outbreak in the community. They housed stable, low-risk COVID-19 patients in CCFs from April to August 2020. These CCFs were created rapidly by converting existing public spaces into isolation facilities, and each was augmented by telemedicine to enable a low health care worker-patient ratio (98 health care workers for 3,200 beds).

In the first month, a total of 3,758 patients were admitted to 4 halls and 4,929 in-house medical consults occurred. The authors report that 136 patients were transferred to a hospital and only 1 patient died 2 weeks after discharge. No health care workers became infected. These results demonstrate that such facilities can successfully provide holistic patient care in the face of a public health crisis when health care resources are lean. Read the full text: https://www.acpjournals.org/doi/10.7326/M20-4746.

Media contacts: A PDF for this article is not yet available. Please click the link to read full text. To speak with the lead author, Kheng Sit Lim, B.Comp, MBBS, MMed(Surg), please contact Carol Ang at carol.ang@sgh.com.sg.

How much time does a brain need to learn a new word? A team of Skoltech researchers and their colleagues monitored changes in brain activity associated with learning new words and found that cortical representations of the sound and meaning of these words may form in just 1 to 2 hours after exposure without any night's sleep consolidation, as earlier research suggested. This research has implications for diagnosing speech disorders and improving the efficiency of learning. The paper was published in the journal Frontiers in Neuroscience.

Consider the word snollygoster, which means someone without principles, especially a politician. It is likely that you did not know this word before, but you do know now -- repeat it several times, and you have learned it. This rather simple and everyday task of learning new words, however, is quite poorly understood in terms of neurocognitive mechanisms that ensure you will remember what snollygoster is days, weeks and years later.

"By nature, every word has two aspects: a particular phonetic pattern that is effectively detected by the brain and the semantics associated with the phonology (an object or an action). In order to dig into the word learning mechanism, one should provide word learning in both aspects: a pseudoword should have original phonetics, i.e. the word should not be constructed from the known roots or other morphemes, and it should acquire original meaning, i.e. not be a synonym for any known word. These restrictions are rather tough to satisfy and control in an experimental setting. The second difficulty is the separation of sematic and phonological processes as they overlap in time and brain localization. Also, the design of effective learning procedure that mobilizes the participant's brain is challenging," Alexandra Razorenova, a coauthor of the paper, explains.

Razorenova and Anna Butorina of the Skoltech Center for Computational and Data-Intensive Science and Engineering (CDISE) in collaboration with the Moscow Center for Neurocognitive Research (MEG Center) tried to look for evidence on how the brain learns both a phonological representation of a new word (how it sounds) and its meaning, or the semantic aspect of new word acquisition. They were also searching for what's called rapid cortical plasticity, i.e. immediate changes in brain activity that follow the learning of a new word. Earlier studies of this particular design have been rare and inconclusive.

The team used magnetoencephalography (MEG) to observe how 24 participants in the experiment learned eight Russian pseudowords carefully designed for the study. A participant had to associate four particular pseudowords with hand and foot movements (so that these pseudowords would mean something). Unlike their colleagues in earlier studies, the researchers did not focus on any specific cortical regions or time intervals, performing an unbiased data search to find neural activity changes induced by word learning.

Not only were they able to observe immediate changes in cortical activity during the process of word learning, but the team also showed that these changes were significantly different for 'meaningful' pseudowords compared to those that were not assigned any meaning.

"The contrast between neural responses elicited by action-associated, and "empty" pseudowords before and after learning procedure answers the question regarding the "semantic network" localization and the relation between sematic and phonological learning. Our findings present the evidence of short-term effortful semantization of word-form and suggest that this semantization facilitates or even triggers strengthening of the cortical network that underlies the phonological aspect of lexicality. That is, "meaningful" pseudowords acquire priority to be recognized and remembered," Razorenova says.

Some earlier electroencephalography and MEG studies also reported rapid cortical plasticity within short experiments; in these studies, repetition suppression was characteristic for real words, while for pseudowords repetition caused response enhancement. Razorenova's group found the opposite to be true. The scientists hypothesize that this might be due to the fact that deep familiarization with word-forms during the experiment completely changed the repetition effect: instead of increasing neural responses to previously unfamiliar word-forms, it decreased them when the word-forms became well-recognized concatenations of phonemes. "The above considerations suggest that our findings most probably reflect a mechanism of familiarization memory that, once formed, lasts over days," Razorenova notes.

The researchers believe their experimental paradigm and data analysis methods will be useful for diagnostics of speech disorders, as it will help differentiate the phonological processes disorders associated with Broca's complex dysfunction from the sematic network failure.

"In a wider perspective, our results evidence the crucial role of interactive learning in contrast with passive learning procedures widely used in the literature. The key role of personal experience, or action or emotion association with the task, are consistent with the Pavlovian learning paradigm. However, this reinforcement method is still underestimated in linguistic methodology. The research may be used as experimental evidence for modification of foreign language learning programs for adults and in programs working with children with developmental disorders of speech and language. These programs should be realized in interactive way with wide usage of simulators of active search and reinforcement," Alexandra Razorenova concludes.

Other organizations involved in this research include Moscow State University of Psychology and Education, Higher School of Economics, and Lomonosov Moscow State University. This research was also supported by a grant from the Russian Foundation for Basic Research 17-29-02168.

In the 2019 Boeing 737 Max crash, the recovered black box from the aftermath hinted that a failed pressure sensor may have caused the ill-fated aircraft to nose dive. This incident and others have fueled a larger debate on sensor selection, number and placement to prevent the reoccurrence of such tragedies.

Texas A&M University researchers have now developed a comprehensive mathematical framework that can help engineers make informed decisions about which sensors to use and where they must be positioned in aircraft and other machines.

"During the early design stage for any control system, critical decisions have to be made about which sensors to use and where to place them so that the system is optimized for measuring certain physical quantities of interest," said Dr. Raktim Bhattacharya, associate professor in the Department of Aerospace Engineering. "With our mathematical formulation, engineers can feed the model with information on what needs to be sensed and with what precision, and the model's output will be the fewest sensors needed and their accuracies."

The researchers detailed their mathematical framework in the June issue of the Institute of Electrical and Electronics Engineers' Control System Letters.

Whether a car or an airplane, complex systems have internal properties that need to be measured. For instance, in an airplane, sensors for angular velocity and acceleration are placed at specific locations to estimate the velocity.

Sensors can also have different accuracies. In technical terms, accuracy is measured by the noise or the wiggles in the sensor measurements. This noise impacts how accurately the internal properties can be predicted. However, accuracies may be defined differently depending on the system and the application. For instance, some systems may require that noise in the predictions do not exceed a certain amount, while others may need the square of the noise to be as small as possible. In all cases, prediction accuracy has a direct impact on the cost of the sensor.

"If you want to get sensor accuracy that is two times more accurate, the cost is likely to be more than double," said Bhattacharya. "Furthermore, in some cases, very high accuracy is not even required. For example, an expensive 4K HD vehicle camera for object detection is unnecessary because first, fine features are not needed to distinguish humans from other cars and second, data processing from high-definition cameras becomes an issue."

Bhattacharya added that even if the sensors are extremely precise, knowing where to put the sensor is critical because one might place an expensive sensor at a location where it is not needed. Thus, he said the ideal solution balances cost and precision by optimizing the number of sensors and their positions.

To test this rationale, Bhattacharya and his team designed a mathematical model using a set of equations that described the model of an F-16 aircraft. In their study, the researchers' objective was to estimate the forward velocity, the direction of wind angle with respect to the airplane (the angle of attack), the angle between where the airplane is pointed and the horizon (the pitch angle) and pitch rate for this aircraft. Available to them were sensors that are normally in aircraft for measuring acceleration, angular velocity, pitch rate, pressure and the angle of attack. In addition, the model was also provided with expected accuracies for each sensor.

Their model revealed that all of the sensors were not needed to accurately estimate forward velocity; readings from angular velocity sensors and pressure sensors were enough. Also, these sensors were enough to estimate the other physical states, like the angle of attack, precluding the need of an additional angle of attack sensor. In fact, these sensors, although a surrogate for measuring the angle of attack, had the effect of introducing redundancy in the system, resulting in higher system reliability.

Bhattacharya said the mathematical framework has been designed so that it always indicates the least sensors that are needed even if it is provided with a repertoire of sensors to choose from.

"Let's assume a designer wants to put every type of sensor everywhere. The beauty of our mathematical model is that it will take out the unnecessary sensors and then give you the minimum number of sensors needed and their position," he said.

Furthermore, the researchers noted that although the study is from an aerospace engineering perspective, their mathematical model is very general and can impact other systems as well.

"As engineering systems become bigger and more complex, the question of where to put the sensor becomes more and more difficult," said Bhattacharya. "So, for example, if you are building a really long wind turbine blade, some physical properties of the system need to be estimated using sensors and these sensors need to be placed at optimal locations to make sure the structure does not fail. This is nontrivial and that's where our mathematical framework comes in."

The stem cells tasked with creating and maintaining biological tissues have a difficult job. They have to precisely divide to form new specialized cells, which are destined to different fates even though they contain identical DNA. An obvious question then is: How do the cells divide in all the right ways to produce a healthy tissue? This was the grand motivating question for Andrew Muroyama, a postdoctoral scholar in the lab of Stanford University biologist Dominique Bergmann, as he monitored days of leaf development in the flowering plant Arabidopsis thaliana. There, amongst a thousand cells under his microscope, he noticed that the nucleus - the DNA-containing control center in the cell - moved in unexpected and strangely purposeful ways as stem cells divided.

Previous research from the Bergmann lab identified a set of proteins that shuffle to one side of the stem cell before division. These proteins seemed to regulate how the stem cell divided, but the actual control mechanisms were unknown. These moving nuclei turned out to be a key to this mystery.

In a paper published Sept. 17 in Current Biology, the researchers report that these asymmetrically distributed proteins act like a compass within the cell to instruct the nucleus where to go. The nuclear position, in turn, controls the patterns of stem cell divisions, which ultimately create tiny pores, called stomata, throughout the leaf surface. Because stomata allow leaves to balance their water and carbon dioxide levels, nuclear alignment via these miniature protein compasses within individual stem cells have the potential to affect leaf function.

"I think our research highlights that the ability to watch the behaviors of cellular machines within living organisms can reveal unexpectedly elegant ways that individual cells cooperate to build tissues," said Muroyama, who is lead author of the paper. "You might think that something as fundamental as cell division would be completely solved by now but there is still so much to learn."

Follow the bouncing nucleus

The Bergmann lab makes Arabidopsis into fluorescent art under the microscope. Bright green nuclei wiggle within purple cell membranes. Watch closely, like Muroyama did, and you would see the usual process for asymmetric cell division: when an Arabidopsis stem cell first divides, the nucleus moves to one side. That way, the resulting daughter cells will be different sizes and will face different neighbors. Eventually, these two cells are destined to play different roles in the intricate final pattern of the leaf.

But continue watching and the nucleus of one daughter cell moves again, hurrying to the opposite side of the cell where it will undergo a second asymmetric split.

"When Andrew showed me the videos of the cells, it was so bizarre," said Bergmann, who is a professor of biology in the School of Humanities and Sciences and senior author of the paper. "I thought, 'Why on Earth would a nucleus behave that way?' The first move makes sense but the second, in the complete opposite direction, was weird."

In order to understand what they were seeing, the researchers conducted several experiments to tease apart the different factors that influence the cells during division.

The researchers already knew about the cellular compass but were unsure what it was guiding or how it worked. By repelling the nucleus before the first division, the compass creates the first set of asymmetric daughters. But by attracting the nucleus immediately afterward, the compass can create a new set of asymmetric daughters on the other side.

"A critical step to understanding the function of the second migration was thinking about the longer history of the stem cells," said Muroyama. "The plant doesn't want to generate new stem cells right next to the ones that were just created. It wants to space them out, so moving the nucleus right after division sets it up for success when creating a second set of daughters."

The researchers also discovered a protein that assists nuclear movement - think a motor that powers the nucleus in the right direction. Disabling that motor prevented the second migration of the nucleus and the resulting leaves had fewer stomata than usual, which could impair the plant's ability to regulate water content and take in carbon dioxide.

It was also known that cells in the leaf surface communicate with each other to regulate stem cell divisions. Curious about whether the cellular compass or cell-to-cell communication was the dominant cue to control how stem cells divide, the researchers modified cells so that they could not receive signals from neighboring cells and watched the bouncing nuclei. Without this communication, the compass appears in the wrong place within the cell, but could still move the nucleus around in predictable ways. This showed that, when it comes to leaf stem cells, the nucleus will follow the instructions from the cellular compass, even if it steers it wrong.

Proving themselves wrong

As a next step, one graduate student in the Bergmann lab is already digging deeper into the purpose of the cellular compass, with particular interest into the different ways this compass can control cell divisions and fate.

More broadly, these findings point to a different way of studying stem cells that focuses less exclusively on the journey of one cell. In some systems, the individual divisions that seem to define a cell's life may actually only be meaningful given what happens next and nearby.

"Looking back 10 years at what we thought was important for a stem cell, we've pretty much proven ourselves wrong," said Bergmann. "We were so focused on the details of what one stem cell did at a specific time and place. Now we understand that history and community matter. We have to look at the stem cell and its mother and grandmother and its neighbors."

BOSTON - Scientists at the Massachusetts General Hospital (MGH) have developed a molecular imaging probe to reveal Alzheimer's disease (AD)-related γ-secretase in rodents and macaques with translational potentials in humans. γ-Secretase is a key player in the etiology of AD and a prime drug target for AD, whose brain regional expression and distribution have yet remain largely unknown. This study describes the development of a molecular imaging probe to reveal γ-secretase in rodents and macaques with translational potentials in humans. This study is to be published in the Journal of Experimental Medicine.

"Our study describes the invention of a positron emission tomography (PET) tracer that enables us to visualize gamma-secretase related to AD," says Changning Wang, PhD, investigator in the Martinos Center for Biomedical Imaging at MGH and co-corresponding author of the study. "The etiology of AD is complex and has not been completely elucidated," says Can (Martin) Zhang, a co-corresponding author and investigator in the Genetics and Aging Research Unit at MGH, a faculty member of the McCance Center for Brain Health in the MassGeneral Institute for Neurodegenerative Disease (MGH-MIND). "These findings may not only better understand the etiology of AD, but also can support the ongoing effort to develop molecules that target gamma-secretase for the treatment and prevention of AD. "

The most common neurodegenerative disorder, AD is characterized by the buildup of amyloid plaques and neurofibrillary tangles in several brain regions. The leading hypothesis for its pathogenesis is the amyloid cascade - which suggests that the amyloid beta-protein, and particularly the amyloid-beta 42 peptide, initiates the disease process. An imbalance between the production and clearance of amyloid-beta results in the protein's aggregation into larger plaques that lead to the death of brain cells and the cognitive symptoms seen in Alzheimer patients. Several potential treatments have been developed that specifically target amyloid, but none have been effective in halting disease progression.

Rudolph Tanzi, PhD, director of the MGH Genetics and Aging Research Unit and co-director of the McCance Center for Brain Heath, a co-corresponding author of this study, and Steven Wagner, PhD, of the USCD Department of Neurosciences, a co-author of the study, first developed the concept of gamma-secretase modulators (GSMs), which preferentially reduce amyloid-beta 42 peptide levels by modulating, without totally suppressing the enzyme's activity, in 2000. Very recently their teams developed a group of soluble GSMs, one of which, SGSM15606, has served as a valuable molecule for better understanding how gamma-secretase contributes to AD pathogenesis.

"Our study takes advantage of the rich expertise of our cross-disciplinary team and uses chemistry, biochemistry, genetics in diverse biomedical technologies on suitable disease models, which has resulted in the discovery of a PET tracer that will open new avenues for us to better understand the complex puzzle and facilitate drug discovery in AD," says Yulong Xu, PhD, investigagor in the Martinos Center and first author of the study.

Wang adds that "our study provides a great example of our effort in developing aging-related probes; additionally, this probe can be used, in combination with our RIPK1 and SIRT1-based novel probes currently under development, to provide a comprehensive and unprecedented level of knowledge in not only AD, but also other aging-related neurodegenerative disorders."

According to a recently published study of Finnish twins, smoking most likely causes a significant share of all cases of subarachnoid haemorrhage, the most fatal type of cerebrovascular disturbances. In the study, smoking was identified as the explanation as to why only one twin in pairs of twins develops a fatal brain haemorrhage. The finding is the first proof of an actual causality between smoking and subarachnoid haemorrhage.

In spite of advances in the treatment of subarachnoid haemorrhage (SAH), it remains the most fatal among cerebrovascular disturbances, with as many as half of the patients dying in the first few months after the haemorrhage.

Due to the high mortality rate, causes leading to this life-threatening disorder that are preventable have been feverishly investigated in recent decades all over the world. Several prior studies have reported a link between smoking and a heightened SAH risk, but no studies have so far been able to demonstrate that smoking directly causes these types of brain haemorrhages. In other words, the problem was similar to the situation with lung cancer several decades ago. It took a long time before evidence was found that smoking causes lung cancer, instead of only being associated with a heightened risk of developing lung cancer in an unknown way.

A study of Finnish twins recently published in Stroke, the world's foremost scientific journal on cerebral circulation, aimed to determine why only one twin in pairs of twins died of a fatal subarachnoid haemorrhage. The follow-up study included specific life-style data on as many as over 13,000 pairs of twins. The study indicates that it is precisely differences in smoking among the twins that appear to explain why only one twin in the pairs, namely the twin who smoked, developed a fatal cerebral haemorrhage, while their non-smoking twin brother or sister did not.

Ilari Rautalin, the principal investigator, says that the finding is historic and enormously important.

"Our findings confirm, for the first time, previous suspicions of an actual causal relation between smoking and fatal brain haemorrhage," says doctoral student Rautalin, Bachelor of Medicine, from the University of Helsinki.

The findings make it likely that smoking causes a significant share of subarachnoid haemorrhages in both men and women, which, in turn, markedly highlights the previously known adverse effects of smoking associated with many other diseases.

The two other members of the research group and authors of the article are Miikka Korja, a neurosurgeon at Helsinki University Hospital, and Jaakko Kaprio, professor of genetic epidemiology at the University of Helsinki.

"It's practically impossible to carry out a conventional clinical trial proving causality with regard to smoking, as it would require exposing healthy individuals to smoking and, subsequently, to many adverse health effects associated with smoking. This is why twin studies are an effective way of demonstrating direct causalities related to smoking," Docent Korja and Professor Kaprio point out.

Rautalin, Korja and Kaprio conclude by emphasising the major importance of quitting smoking or never starting the habit in the first place to minimise the risk of fatal cerebral haemorrhage.