Those who have less than two hours a day of recreational screen time do better in testing, a study suggests.
Limiting children’s screen time linked to better cognition
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Category Archives: Mind Building
Ambulances not an A&E taxi service, NHS warned
Review criticises ageing fleet, high sickness rates and slow uptake of technology in England.
Scientists investigate how DEET confuses countless critters
DEET, thought to be the most effective insect repellent available, may not be an insect repellent at all.
It’s not that DEET doesn’t keep away critters — it verifiably does. However, Leslie B. Vosshall, Rockefeller’s Robin Chemers Neustein Professor, has shown that DEET acts not by repelling bugs, but rather by confusing them, messing with neurons that help the animals smell their surroundings. Moreover, the effects of DEET are not limited to insects: spiders, ticks, and many other pests also act strangely in the chemical’s presence.
In this sense, DEET may be less of an insect repellent and more of an invertebrate confusant. The term doesn’t exactly roll off the tongue, but new research from the Vosshall lab supports this rebranding of the chemical.
In a recent paper, published in Nature, Vosshall and former graduate fellow Emily Dennis show that, like insects, the nematode C. elegans succumbs to confusion when DEET is around. The team also describes the genetic and cellular mechanisms underlying this response, shedding light on how a single chemical might confound the senses of vastly different species.
All in the DEET-ails
First developed in the 1940s, DEET can be found in most bug sprays used today. Research has shown that, in flies and mosquitoes, the chemical works by interacting with odor receptors that are unique to insects. This research, however, cannot explain how DEET exerts its effect on non-insect species.
Seeking an explanation, Dennis and Vosshall teamed up with Cori Bargmann, Rockefeller’s Torsten N. Wiesel Professor, to examine whether and how DEET changes the behavior of the roundworm C. elegans, a relatively simple animal with an elaborate sense of smell. When the researchers presented the tiny worms with samples of DEET alone, the animals didn’t go out of their way to avoid the chemical, indicating that DEET doesn’t simply repel every organism that crosses its path.
The scientists then mixed small amounts of DEET into agar, the gel-like substance that C. elegans crawl on in Petri dishes. The presence of DEET limited the worms’ movement toward isoamyl alcohol, a chemical that usually attracts them; it also reduced their avoidance of 2-nonanone, a compound that they typically dodge. Still, the worms reacted normally to some other chemicals. These findings suggest that DEET can interfere with responses to both “good” and “bad” smells, but that it does not entirely shut down olfaction.
The researchers also found that the worms’ DEET sensitivity depends on a gene called str-217, which is expressed in neurons called ADL cells. When the researchers artificially activated these neurons, the worms paused in place — a behavior also observed among C. elegans navigating DEET-infused agar. Together, these results indicate that the chemical works, in part, by turning on neurons that induce pausing.
“Somehow activating ADL puts the worms into a frame of mind where they’re more introspective, they’re pausing more, they’re not paying as much attention to odors,” says Vosshall. “But if you take away the right gene or neuron, this spell is broken.”
Indeed, the researchers showed that worms lacking either str-217 or ADL neurons are less affected by DEET. They conclude that str-217 likely codes for a DEET receptor, and that ADL cells play an important role in mediating response to the chemical.
A special chemical
The Vosshall lab previously demonstrated that DEET keeps mosquitoes away by interacting with odor receptors in a way that confuses the animals’ sense of smell. This latest study shows that DEET causes similar confusion in C. elegans, but through entirely different mechanisms.
“We went into this study thinking perhaps we’d find some magical conserved DEET receptor common to all species,” says Dennis. “But we found that, in C. elegans, a completely unique gene is required for DEET response.”
Though the study did not lead to the discovery of a magical receptor, it nonetheless provides insight into the chemical’s effectiveness across highly diverse species.
“The one common theme in all of these organisms is that DEET is doing something to affect odor perception — it’s like sensory system sabotage,” says Vosshall.
Dennis adds: “Something about DEET is really special. And I think we’re just starting to uncover all the ways that it can affect different neurons, receptors, and species.”
Powerful jet discovered coming from ‘wrong’ kind of star
Astronomers using the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) have discovered a fast-moving jet of material propelled outward from a type of neutron star previously thought incapable of launching such a jet. The discovery, the scientists said, requires them to fundamentally revise their ideas about how such jets originate.
Neutron stars are superdense objects, the remnants of massive stars that exploded as supernovas. When in binary pairs with “normal” stars, their powerful gravity can pull material away from their companions. That material forms a disk, called an accretion disk, rotating around the neutron star. Jets of material are propelled at nearly the speed of light, perpendicular to the disk.
“We’ve seen jets coming from all types of neutron stars that are pulling material from their companions, with a single exception. Never before have we seen a jet coming from a neutron star with a very strong magnetic field,” said Jakob van den Eijnden of the University of Amsterdam. “That led to a theory that strong magnetic fields prevent jets from forming,” he added.
The new discovery contradicts that theory.
The scientists studied an object called Swift J0243.6+6124 (Sw J0243), discovered on October 3, 2017, by NASA’s orbiting Neil Gehrels Swift Observatory, when the object emitted a burst of X-rays. The object is a slowly-spinning neutron star pulling material from a companion star that is likely significantly more massive than the Sun. The VLA observations began a week after the Swift discovery and continued until January 2018.
Both the fact that the object’s emission at X-ray and radio wavelengths weakened together over time and the characteristics of the radio emission itself convinced the astronomers that they were seeing radio waves produced by a jet.
“This combination is what we see in other jet-producing systems. Alternative mechanisms just don’t explain it,” van den Eijnden said.
Common theories for jet formation in systems like Sw J0243 say the jets are launched by magnetic field lines anchored in the inner parts of the accretion disks. In this scenario, if the neutron star has a very strong magnetic field, that field is overpowering and prevents the jet from forming.
“Our clear discovery of a jet in Sw J0243 disproves that longstanding idea,” van den Eijnden said.
Alternatively, the scientists suggest that Sw J0243’s jet-launching region of the accretion disk could be much farther out than in other types of systems, where the star’s magnetic field is weaker. Another idea, they said, is that the jets may be powered by the neutron star’s rotation, instead of being launched by magnetic field lines in the inner accretion disk.
“Interestingly, the rotation-powered idea predicts that the jet will be significantly weaker from more slowly rotating neutron stars, which is exactly what we see in Sw J0243,” Nathalie Degenaar, also of the University of Amsterdam, said.
The new discovery also implies that Sw J0243 may represent a large group of objects whose radio emission has been too weak to detect until new capabilities provided by the VLA’s major upgrade, completed in 2012, were available. If more such objects are found, the scientists said, they could test the idea that jets are produced by the neutron star’s spin.
The astronomers added that a jet from SwJ0243 may mean that another category of objects, called ultra-luminous X-ray pulsars, also highly magnetized, might produce jets.
“This discovery not only means we have to revise our ideas about jets from such systems, but also opens up exciting new areas of research,” Degenaar said.
Van den Eijnden, Degenaar, and their colleagues are reporting their discovery in the journal Nature.
The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
Fossil evidence of large flowering trees in N. America 15 millions years earlier
A newly discovered fossil suggests that large, flowering trees grew in North America by the Turonian age, showing that these large trees were part of the forest canopies there nearly 15 million years earlier than previously thought. Researchers from Adelphi University and the Burpee Museum of Natural History found the fossil in the Mancos Shale Formation in Utah, in ancient delta deposits formed during a poorly understood interval in the North American fossil record.
“These discoveries add much more detail to our picture of the landscape during the Turonian period than we had previously,” says Michael D’Emic, assistant professor of biology at Adelphi, who organized the study. “Since Darwin, the evolution of flowering plants has been a topic of debate for paleontologists because of their cryptic fossil record. Our paper shows that even today it is possible for a single fossil specimen to change a lot about what we know about the early evolution of the group.
“Understanding the past is the key to managing the future,” D’Emic added. “Learning how environments evolved and changed in the past teaches us how to better prepare for future environmental change.”
Aside from the large petrified log, the team reports fossilized foliage from ferns, conifers and angiosperms, which confirm that there was forest or woodland vegetation 90 million years ago in the area, covering a large delta extending into the sea. The team also reports the first turtle and crocodile remains from this geologic layer, as well as part of the pelvis of a duck-billed dinosaur; previously, the only known vertebrate remains found were shark teeth, two short dinosaur trackways, and a fragmentary pterosaur.
“Until now most of what we knew about plants from the Ferron Sandstone came from fossil pollen and spores,” says Nathan Jud, co-author and assistant professor of biology at William Jewell College. “The discovery of fossil wood and leaves allows us to develop a more complete picture of the flora.”
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Health24.com | When should you use laxatives?
There are many different views of constipation. Some people believe that not having a daily bowel movement constitutes constipation. This is not true – some people have bowel movements three times a day, while others “go” only about twice a week. If your stools are soft and pass easily, you are not constipated.
People who are under the impression that they are constipated may resort to laxatives,.
But when should you, and when shouldn’t you use laxatives?
Use laxatives
Almost everyone will suffer from constipation at some point in their lives, but in most cases it is quickly resolved.
An adult who has not had a bowel movement in three days or a child who has not had a bowel movement in four days is considered constipated.
When experiencing constipation, rather than addressing their lifestyle, people may turn to laxatives.
There are many different kinds, most of which are available over-the-counter without a prescription.
According to NHS Choices, laxatives should only be used occasionally and for short periods of time. You should also stop taking laxatives when constipation improves.
Faecal impaction
According to the GI Society, the regular use or abuse of laxatives, with the exception of bulk-forming agents and stool softeners, can lead to serious dysfunction of bowel motility, such as intestinal paralysis, cathartic colon, lazy or laxative gut, irritable bowel syndrome, pancreatitis, and other problems.
In the case of chronic constipation, it is better to seek the care of a medical professional before self-treating with over-the-counter laxatives.
The most serious constipation scenario is faecal impaction, when the stool hardens in the rectum and becomes lodged. Only then, in many cases, will people seek medical help.
According to Medline Plus, faecal impaction often occurs in people who have been constipated and using laxatives for a long time.
This is more likely to happen when the laxatives are suddenly stopped because the muscles of the intestines have forgotten how to move stool on their own.
Lack of movement, certain diseases and some medications increase the risk of feacal impaction.
Good bowel movements without laxatives
Health24 suggests these lifestyle changes to help avoid or find relief from constipation:
- Add more fibre to your diet by eating more fruit, vegetables, legumes and whole-grain or bran products.
- Eat more foods that act as natural laxatives effect such as prunes and linseeds (flaxseeds).
- Add a bulking agent to your diet. Examples include bran and psyllium husk, which work by increasing the volume of the stool, making it easier to pass. Always drink enough water when using bulking agents.
- Drink plenty of water. Try to drink 6–8 glasses of water daily in addition to other beverages.
- Decrease your alcohol and caffeine (coffee, tea and certain carbonated drinks) intake. These substances are diuretics, which means they remove water from the body.
- Exercise regularly, as this can help activate bowel movements.
- Don’t delay if you feel the need to have a bowel movement, as this can worsen constipation.
- Try placing your feet on a low stool while going to the toilet, so that your knees are above your hips. This can make it easier to pass stools.
Image credit: iStock
Health24.com | Historic UN TB declaration ‘falls short’ say activists
Civil society groups have criticised the United Nations declaration on tuberculosis (TB) ratified yesterday saying it ‘falls short’ on critical issues in the fight against the world’s top infectious killer.
Groups including the Health Global Access Project, the Treatment Action Group and South Africa’s Section27 and Treatment Action Campaign said that TB declaration being ratified by United Nations (UN) member states “falls short on its response to the leading infectious killer worldwide and the leading cause of death for people with HIV”.
The statement was released ahead of the first-ever UN high-level meeting on TB in New York, which will see heads of state and political leaders commit to intensify efforts in tackling the disease.
They said that to “get serious about ending TB” and “to finally confront an infectious disease killing 4 500 people per day”, countries need to commit to a number of concrete interventions. These include the rapid scale-up of a new TB test called LAM, used for hard-to-diagnose patients living with HIV that uses urine instead of sputum to detect TB.
According to the international non-profit organisation, the Foundation for Innovative New Diagnostics (FIND) up to 60% of people with HIV are unable to produce a sputum sample, leading to delays in TB diagnosis for these patients, which often proves deadly.
FIND, along with Fujifilm, developed the LAM test and announced “promising” preliminary results of their test in New York on Wednesday.
However, FIND’s head of communications, Sarah-Jane Loveday. told Health-e News that “we can’t release [details of] the results of the study as the manuscript is currently being peer-reviewed. All we can say at this point is that they were very encouraging”.
The test will be particularly useful in low-income settings, where the burden of HIV and TB is the highest, because it takes an hour to produce results, doesn’t rely on electricity and requires limited training for health workers.
Deputy Director General for Health Dr Yogan Pillay told Health-e News last year that the TB LAM test, which costs just R40, had recently been introduced in South Africa and was being scaled up.
At a side-event of the UN meeting, president of the International Union Against Tuberculosis and Lung Disease (The Union) Dr Jeremiah Chakaya Muhwa also called on governments to take urgent action against TB.
“We need a revolution in prevention… We must support efforts to get an effective TB vaccine,” he said.
On Tuesday promising primary clinical trial results for a candidate TB vaccine were published in the New England Journal of Medicine. The candidate is the closest the world has come to developing a new TB vaccine in over 100 years.
The number of people who developed TB was slashed in half in people who received the vaccine compared to those who did not.
The Union’s Dr Paula Fujiwara said that these results “are a major milestone in the development of a new TB vaccine”.
“Leaders have committed to ending the global TB epidemic by 2030, and we need a new TB vaccine to have a shot at meeting that goal.
Despite being preventable and curable, TB still killed around 1.6 million people in 2017.
Civil society groups laid some of the blame for this on the gap in funding allocated to TB research. They called on governments to recognise their “collective and individual failures” and commit to investing at least 0.1 percent of their annual expenditure on research and development in TB.
“Relative to other major killers, TB gets a pittance of research funding,” said Fujiwara, who added that there is an annual $1.2bn shortfall for what is needed.
“National leaders should interpret [the] new vaccine data as reason to double down on their research investments. The great thing is they’re committed to do exactly that at the UN this week. Now they need to follow through,” she said.
– Health-e News
Health24.com | 8 signs you have anxiety that’s messing with your life
I have generalised anxiety disorder (GAD).
When I explain it to people, they often say something like, “Well, yeah, I feel anxious sometimes, too” – which, honestly, tells me they don’t really get it.
Feeling anxious once in a while and having anxiety are two very different things – the former constitutes normal day-to-day worries, while the latter begins with a thought or feeling that you become fixated upon, leading you down a rabbit hole of anxiety, sometimes coupled with legit physical symptoms (like a racing heart and profuse sweating).
“Anxiety is a normal part of life,” says Dr Crystal Lee, owner of LA Concierge Psychologist. “However, when your anxiety seems to extend to all aspects of your life, not just a current anxiety-provoking situation, you might have an anxiety disorder.”
Of course, my anxiety disorder, GAD, isn’t the only anxiety disorder out there – other anxiety disorders include panic disorder (a sudden and intense fear that comes and leaves within minutes, a.k.a., a panic attack) and phobia-related disorders (an intense fear of a specific thing, like spiders or closed spaces), per the National Institute of Mental Health.
But all anxiety disorders have a common thread: That anxiety is constant and interferes with your daily life – and it needs treatment. Here’s how to know if your anxious feelings are just that – or if you’re dealing with an actual anxiety disorder.
1. Your anxious thoughts don’t go away.
If you have an anxiety disorder, you tend to be become extremely anxious in situations where your friends or family might get only a little anxious, Dr Lee says. Like during a yearly family gathering, for example.
“Your anxiety also tends to be long-lasting or persistent; it never seems to dissipate,” she says. “When our anxiety begins impacting your daily life and ability to live a fulfilling life,” that’s when it becomes an issue, she says.
Read more: How these 4 common antidepressants and anxiety meds affect your body
2. Your anxiety is coupled with other symptoms.
GAD can also manifest as physical conditions, including muscular pain, restlessness and fatigue, among others, says Dr LA Barlow, of Barlow Professional Services PC.
And don’t be surprised if you also experience gastrointestinal issues, says Barlow. Anxiety disorders can lead to GI upset, including diarrhoea, cramping and heartburn, since your body is always in a heightened state of anxiety (there’s a reason why some people feel physically ill from nerves – the gut-mind connection is very strong, says Dr Barlow).
3. You can’t focus.
It’s not uncommon for people with GAD to be mistakenly perceived as having attention deficit hyperactivity disorder (ADHD), Dr Lee says.
That’s because individuals with anxiety disorders often have a difficult time focusing. “You are constantly in your head and get distracted by all the obsessions and negativity rattling around in there,” she says. “To an outsider, it looks like you have ADHD.”
Read more: 7 women share what got them through suicidal thoughts
4. You actually worry about worrying.
Yes, many anxiety disorders are triggered by specific worries: GAD, for example, might make you worry about the unknown, like what your future holds; while a phobia might make you fear the immediate, like a spider dropping down in front of you.
But anxiety disorders can also make you have anxiety about having anxiety, says Dr Lee. It sounds exhausting, but for those with anxiety disorders, worrying can become cyclical and lead to even more worrying.
5. You’re always afraid of making the ‘wrong’ decision.
If you are dealing with an anxiety disorder, then Dr Lee says your decision-making skills become pretty much shot.
Anxiety disorders “make you indecisive because you fear making the wrong choice,” she says. “You fall into an endless pit of worries as you think about all the endless possibilities and outcomes to your decisions – and that worry can be paralysing.”
Read more: 5 Instagram accounts that will help ease your end-of-year anxiety
6. You want to avoid all of the things.
It’s not uncommon for a person with an anxiety disorder to avoid situations – no matter the level of importance – in order to quell excessive feelings of anxiousness, Dr Barlow says.
But Dr Lee points out that that avoidance actually feeds into anxiety disorders, too. “The relief you feel from escaping anxiety-provoking situations reinforces anxiety,” she says. “Instead, you should learn to accept and cope with anxiety, which takes its power away.”
7. You find it impossible to snooze.
Anxiety has a way of taking your thoughts on a ride that leaves you unable to catch some shut-eye. (At the height of my GAD, I’d be up for several hours in the middle of the night.) According to the Anxiety and Depression Association of America (ADAA), some level of sleep disruption is present in nearly all psychiatric disorders, including anxiety disorders.
8. You always see the glass as half empty.
It’s not uncommon for anxiety disorders to strip you of any optimism or hope for the future, Dr Lee says. “As a result, as you think about the different outcomes for your decisions, they often lead to one conclusion: It will suck,” she says. “The future seems bleak and hopeless. You feel out of control.”
So what do you do if you think you have an anxiety disorder?
If your symptoms checked a lot of the boxes above, there’s a good chance you might be dealing with an anxiety disorder. But before you make assumptions, Dr Barlow says it’s important to first make sure you rule out other possibilities, seeing as how symptoms of anxiety (like fatigue or stomach upset) can mimic other health conditions.
Once you have a diagnosis: “The most helpful thing you can do if you struggle with anxiety is to get professional help,” Dr Lee says, adding that sleep, eating healthfully and staying active can help alleviate symptoms of anxiety. Treatment for anxiety disorders can also include cognitive behavioral therapy (CBT), coping skills and possibly even medication.
There are two major categories of medication that are used to treat anxiety: Antidepressants and anti-anxiety medications, says Dr Lee. Antidepressants are seen as long-term treatments for anxiety, while anti-anxiety medications are a short-term way to relieve physical symptoms like muscle tension or shaking.
Yes, anxiety is a mental health condition that can be pretty debilitating, but “with the correct intervention, an individual can live a very fulfilling life,” says Dr Lee.
This article was originally published on www.womenshealthmag.com
Image credit: iStock
Contaminated blood scandal: We are sorry, says government
Lawyers for the government tell public inquiry, “things happened that should not have happened”.
Fall in strength and fitness of 10-year-olds, study shows
The children were heavier and taller but scored worse in strength and fitness tests, the study found.
