Knowledge Update

New York, Dec 23 (IANS) You can literally lose sleep over discrimination as a new study has found that people who perceive more unfairness in daily life have higher rates of sleep problems.

"Discrimination is an important factor associated with sleep measures in middle-aged adults," according to the study by Sherry Owens of West Virginia University in the US, and colleagues. 

The research included 441 adults from a study of health and well-being in middle age and beyond (the MIDUS Study). The participants' average age was 47 years. 

Participants wore an activity monitor device for one week to gather data on objective sleep measures -- for example, sleep efficiency, calculated as the percentage of time spent in bed that the person was asleep. 

They also completed subjective sleep ratings -- for example, how often they had sleep problems.

Perceived experiences of discrimination were assessed using a validated "Everyday Discrimination Scale." 

For example, participants were asked how often they were treated with less courtesy or respect than others, or how often they were insulted or harassed.

Participants who perceived more discrimination had increased sleep problems, according to the study published in Psychosomatic Medicine: Journal of Biobehavioral Medicine.

Higher discrimination scores were associated with 12 per cent higher odds of poor sleep efficiency and a nine percent increase in the odds of poor sleep quality. 

Discrimination was also related to (objective) time spent awake after falling asleep and (subjective) overall sleep difficulties.

While poor sleep has previously been linked to higher perceived discrimination, the researchers said that the new study is the first to look at how discrimination affects both objective and subjective sleep measures.

"The findings support the model that discrimination acts as a stressor than can disrupt subjective and objective sleep," the study said.

New York, Dec 23 (IANS) Researchers have developed a new tattoo ink that glows only under certain light conditions and disappears later. It can better help in surgical treatment of patients with a form of skin cancer much more than the commercially available tattoo pigments.

Tattoos may not be just for body art, but are also used by the medical community for precisely demarcating future treatment landmarks. 

This is especially important for identifying biopsy sites of nonmelanoma skin cancer (NMSC) patients as they typically have to wait up to three months between a biopsy confirming their condition and treatment. 

However, the commercially available tattoo pigments inks can cause discomfort and inflammation.

The new ink developed by researchers led by Kai Chen University of Southern California is time-limited. Under ambient lighting, the nanoparticles are invisible, which would avoid unwanted markings in a patient's skin, and is a safer, more patient-friendly option. 

Testing in mice showed that tattoos created with these nanoparticles did not cause inflammation and lasted for three months. 

The study was published in the journal ACS Nano.

​London, Dec 23 (IANS) In a large human trial led by the World Health Organisation (WHO), an experimental Ebola vaccine was found highly protective against the deadly virus, promising an effective weapon against any future outbreak.

The vaccine is the first to prevent infection from one of the most lethal known pathogens, according to the results published in The Lancet journal. 

"While these compelling results come too late for those who lost their lives during West Africa's Ebola epidemic, they show that when the next Ebola outbreak hits, we will not be defenceless," said Marie-Paule Kieny, WHO's Assistant Director-General for Health Systems and Innovation, and the study's lead author.

In the most recent Ebola outbreak in West Africa that started in late 2013, more than 11,000 people lost their lives. The WHO removed the global emergency tag for the disease early this year.

The vaccine, called rVSV-ZEBOV, was studied in a trial involving 11,841 people in Guinea during 2015. 

Among the 5,837 people who received the vaccine, no Ebola cases were recorded 10 days or more after vaccination. 

In comparison, there were 23 cases 10 days or more after vaccination among those who did not receive the vaccine.

The trial was led by the World Health Organization, together with Guinea's Ministry of Health and other international partners.

The vaccine's manufacturer, Merck, Sharpe & Dohme, this year received Breakthrough Therapy Designation from the United States Food and Drug Administration and PRIME status from the European Medicines Agency, enabling faster regulatory review of the vaccine once it is submitted.

Since Ebola virus was first identified in 1976, sporadic outbreaks have been reported in Africa. 

But the 2013-2016 West African Ebola outbreak, which resulted in more than 11,300 deaths, highlighted the need for a vaccine.

The trial took place in the coastal region of Basse-Guinée, the area of Guinea still experiencing new Ebola cases when the trial started in 2015. 

To assess safety, people who received the vaccine were observed for 30 minutes after vaccination, and at repeated home visits up to 12 weeks later. 

Approximately half reported mild symptoms soon after vaccination, including headache, fatigue and muscle pain but recovered within days without long-term effects. 

Two serious adverse events were judged to be related to vaccination (a febrile reaction and one anaphylaxis) and one was judged to be possibly related (influenza-like illness). 

All three recovered without any long term effects, the study reported.

London, Dec 22 (IANS) Researchers have shown that instead of expensive equipment, smartphones can be used to make movies of living cells and observe their response to different treatments.

Live imaging of cells is a very powerful tool for the study of cells, to learn about how cells respond to different treatments such as drugs or toxins.

The study published in the journal PLOS ONE showed that a simple smartphone can replace expensive equipment used for the process.

"The technology presented here can readily be adapted and modified according to the specific need of researchers, at a low cost," said Johan Kreuger from Uppsala University in Sweden.

"Indeed, in the future, it will be much more common that scientists create and modify their own research equipment, and this should greatly propel technology development," Kreuger said.

In the present study, old standard inverted microscopes that are very abundant at universities and hospitals were upgraded to high quality live imaging stations using a few 3D-printed parts, off-the-shelf electronics, and a smartphone. 

It was shown that the resultant upgraded systems provided excellent cell culture conditions and enabled high-resolution imaging of living cells.

London, Dec 22 (IANS) British researchers have developed a breakthrough technique that uses sound rather than light to see inside live cells, a finding that has potential application in stem-cell transplants and cancer diagnosis.

The new sub-optical phonon (sound) imaging technique uses shorter-than-optical wavelengths of sound and could even rival the optical super-resolution techniques. 

It provides invaluable information about the structure, mechanical properties and behaviour of individual living cells at a scale not achieved before.

"Like ultrasound on the body, ultrasound in the cells causes no damage and requires no toxic chemicals to work. Because of this, we can see inside cells that one day might be put back into the body, for instance as stem-cell transplants," said Matt Clark, Professor at the University of Nottingham in Britain.

In optical microscopy, which uses light (photons), the size of the smallest object you can see or the resolution is limited by the wavelength.

For biological specimens, the wavelength cannot go smaller than that of blue light because the energy carried on photons of light in the ultraviolet and shorter wavelengths is so high it can destroy the bonds that hold biological molecules together damaging the cells.

Also, the fluorescent dyes used in optical super-resolution imaging are often toxic and it requires huge amounts of light and time to observe and reconstruct an image which is damaging to cells.

However, sound does not have a high-energy payload. This uses smaller wavelengths and enables to see smaller things and get higher resolution images without damaging the cell biology, the researchers noted.

The study is published in the journal Scientific Reports.

New York, Dec 22 (IANS) A distinctive neural signature found in the brains of people with dyslexia may explain why they have difficulty in learning to read and adapting to sensory inputs, according to a new study.

The brain typically adapts rapidly to sensory input, such as the sound of a person's voice or images of faces and objects, as a way to make processing more efficient. 

But, the study found that for individuals with dyslexia, the adaptation was on average nearly half.

In dyslexic people, the brain has a diminished ability to acclimate to a repeated input -- a trait known as neural adaptation. 

For example, when dyslexic students see the same word repeatedly, brain regions involved in reading do not show the same adaptation seen in typical readers.

This suggests that the brain's plasticity, which underpins its ability to learn new things, is reduced, said John Gabrieli, professor at Massachusetts Institute of Technology (MIT) in the US.

"It's a difference in the brain that's not about reading per se, but it's a difference in perceptual learning that's pretty broad," Gabrieli added.

For the study, the team used MRI technique where the brains of young adults with and without reading difficulties were scanned as they listened to a series of words read by either four different speakers or a single speaker.

The results revealed that the dyslexic participants showed much less adaptation to hearing words said by a single speaker.

Further, for dyslexics the brain activity remained high while listening to a consistent voice and not to multiple voices, suggesting that they did not adapt as much. 

Again, when researchers looked at adaptation to visual stimuli, they saw much less adaptation in participants with dyslexia.

"This suggests that adaptation deficits in dyslexia are general, across the whole brain," noted Tyler Perrachione, assistant professor at Boston University in Massachusetts, US. 

The study appears in the journal Neuron.

​Washington, Dec 22 (IANS) A NASA satellite instrument orbiting Earth that can see through fog, clouds and darkness has given scientists their first continuous look at the boom-and-bust, or peak and decline, cycles of phytoplankton - foundation of the ocean's food web vital for life to exist on earth.

The results showed that small, environmental changes in polar food webs significantly influence the boom-and-bust cycles of phytoplankton. 

The researchers believe that the findings - published in the journal Nature Geoscience - will supply important data for ecosystem management, commercial fisheries and our understanding of the interactions between Earth's climate and key ocean ecosystems.

"It's really important for us to understand what controls these boom-and-bust cycles, and how they might change in the future so we can better evaluate the implications on all other parts of the food web," said Michael Behrenfeld, a marine plankton expert at Oregon State University in Corvallis, US.

Coastal economies and wildlife depend on what happens to tiny green plants, or phytoplankton, at the base of the ocean food chain. Commercial fisheries, marine mammals and birds all depend on phytoplankton blooms.

Phytoplankton also influence Earth's carbon cycle. Through photosynthesis, they absorb a great deal of the carbon dioxide dissolved in the upper ocean and produce oxygen, which is vital for life on Earth. This reduces the amount of carbon dioxide in the atmosphere.

NASA's Cloud-Aerosol LIdar with Orthogonal Polarization (CALIOP), an instrument aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite launched in 2006, uses a laser to take measurements. 

Scientists used the instrument to continuously monitor plankton in polar regions from 2006 to 2015.

"CALIOP was a game-changer in our thinking about ocean remote sensing from space," said Chris Hostetler, a research scientist at NASA's Langley Research Center in Hampton, Virginia.

"We were able to study the workings of the high-latitude ocean ecosystem during times of year when we were previously completely blind," Hostetler noted.

London, Dec 20 (IANS) Using the latest satellite data that helps create an 'x-ray' view of the planet, scientists discovered a jet stream within the Earth's molten iron core.

"The European Space Agency's Swarm satellites are providing our sharpest x-ray image yet of the core. We've not only seen this jet stream clearly for the first time, but we understand why it's there," said lead researcher Phil Livermore from the University of Leeds in Britain.

"We can explain it as an accelerating band of molten iron circling the North Pole, like the jet stream in the atmosphere," Livermore said.

Because of the core's remote location under 3,000 kilometres of rock, for many years scientists have studied the Earth's core by measuring the planet's magnetic field - one of the few options available.

Previous research had found that changes in the magnetic field indicated that iron in the outer core was moving faster in the northern hemisphere, mostly under Alaska and Siberia.

But new data from the Swarm satellites revealed these changes are actually caused by a jet stream moving at more than 40 kilometres per year.

This is three times faster than typical outer core speeds and hundreds of thousands of times faster than the speed at which the Earth's tectonic plates move.

The European Space Agency's Swarm mission features a trio of satellites which simultaneously measure and untangle the different magnetic signals which stem from the Earth's core, mantle, crust, oceans, ionosphere and magnetosphere. 

They have provided the clearest information yet about the magnetic field created in the core, according to the scientists.

The study, published in the journal Nature Geoscience, found the position of the jet stream aligns with a boundary between two different regions in the core. 

The jet is likely to be caused by liquid in the core moving towards this boundary from both sides, which is squeezed out sideways.

"This feature is one of the first deep-Earth discoveries made possible by Swarm. With the unprecedented resolution now possible, it's a very exciting time - we simply don't know what we'll discover next about our planet," Rune Floberghagen, ESA's Swarm mission manager, said.

​New York, Dec 20 (IANS) Researchers have developed the first vaccine for chikungunya fever made from an insect-specific virus that does not have any effect on people, making the vaccine safe and effective.

The newly developed vaccine quickly produces a strong immune defence and completely protects mice and non-human primates from disease when exposed to the chikungunya virus, showed the findings detailed in the journal Nature Medicine.

"This vaccine offers efficient, safe and affordable protection against chikungunya and builds the foundation for using viruses that only infect insects to develop vaccines against other insect-borne diseases," said study senior author Scott Weaver, Professor at the University of Texas Medical Branch at Galveston in the US.

Chikungunya is a mosquito-borne virus that causes a disease characterised by fever and severe joint pain, often in hands and feet, and may include headache, muscle pain, joint swelling or rash. 

There is currently no commercial chikungunya vaccine.

Traditionally, vaccine development involves tradeoffs between how quickly the vaccine works and safety. 

Live-attenuated vaccines that are made from weakened versions of a live pathogen typically offer rapid and durable immunity but reduced safety. 

On the other hand, the inability of inactivated vaccines to replicate enhances safety at the expense of effectiveness, often requiring several doses and boosters to work properly. 

There may be a risk of disease with both of these vaccine types, either from incomplete inactivation of the virus or from incomplete or unstable weakening of the live virus that is only recognised when rare vulnerable individuals contract disease.

To overcome these tradeoffs, the researchers used the Eilat virus as a vaccine platform since it only infects insects and has no impact on people. 

The researchers used an Eilat virus clone to design a hybrid virus-based vaccine containing chikungunya structural proteins.

The Eilat/Chikungunya vaccine was found to be structurally identical to natural chikungunya virus. 

The difference is that although the hybrid virus replicates very well in mosquito cells, it cannot replicate in mammals.

Within four days of a single dose, the candidate vaccine induced neutralising antibodies that lasted for more than 290 days. 

The antibodies provided complete protection against chikungunya in two different mouse models. 

In non-human primates, the vaccine elicited rapid and robust immunity -- there was neither evidence of the virus in the blood nor signs of illness such as fever after chikungunya virus infection, the study said.

​London, Dec 20 (IANS) Young girls who exhibit a poor mastery of fundamental movement skills (FMS) such as running, catching and balance are more likely to be obese than boys who have similarly low skills, according to a research.

Previous studies have shown that primary school children with a higher body mass index are likely to have poorer fundamental movement skills.

For the new study, the team assessed running, catching and balance skills of 250 girls and boys between 6-11 years, categorising their FMS as either low, medium or high.

The researchers then cross-referenced the kids' motor skills with their body fatness to investigate the relationship between the two. The children's habitual physical activity was also taken into account.

The results showed that body fatness was significantly higher among girls in the low FMS category compared with boys as well as girls with high FMS.

"What we've found is significant because it signals a need to review the strategies we have to enhance motor proficiency in girls," said lead researcher Mike Duncan, professor at Coventry University in Britain.

"The next big question is whether developmental delays in acquiring these motor skills, whether in girls or boys, may actually be the cause of children gaining unhealthy weight status," Duncan said.

The study was presented recently at the British Association of Sport and Exercise Sciences Conference 2016 in Nottingham, Britain.