Best selection of daily science news!
În acestă categorie publicăm regulat cele mai importante ştiri din ştiinţă şi tehnologie în limba engleză.
Ştirile sunt preluate de pe site-uri de prestigiu în limba engleză, pentru care avem drept de republicare.

Comentarii -

(Timp citire: 4 - 5 minute)
File 20171127 2004 mbwiv5.jpg?ixlib=rb 1.1
CSIRO Parkes radio telescope has discovered around half of all known pulsars. Wayne England, Author provided

George Hobbs, CSIRO; Dick Manchester, CSIRO, and Simon Johnston, CSIRO

A pulsar is a small, spinning star – a giant ball of neutrons, left behind after a normal star has died in a fiery explosion.

With a diameter of only 30 km, the star spins up to hundreds of times a second, while sending out a beam of radio waves (and sometimes other radiation, such as X-rays). When the beam is pointed in our direction and into our telescopes, we see a pulse.

2017 marks 50 years since pulsars were discovered. In that time, we have found more than 2,600 pulsars (mostly in the Milky Way), and used them to hunt for low-frequency gravitational waves, to determine the structure of our galaxy and to test the general theory of relativity.

Comentarii -

(Timp citire: 7 - 8 minute)


by Bahar Gholipour

For a number of years in the 1980s, applicants to St George’s Hospital Medical School in London were selected with a high-tech method. A computer program, one of the first of its kind, took the first look at their résumés, carrying out the initial selection of about 2,000 candidates every year. The program analyzed the admissions records to learn the characteristics of successful applications, and was adjusted until its decisions matched those of the admissions team.

But the program had learned to look for more than good grades and signs of academic prowess. Four years after the program was implemented, two doctors at the hospital discovered the program tended to reject female applicants and those with non-European-sounding names, regardless of their academic merit. As many as 60 applicants each year could have been refused an interview simply because of their gender or race, the doctors found. The program had incorporated the gender and racial biases in the data used to train it — it was essentially taught that women and foreigners were not doctor material.

Comentarii -

(Timp citire: 4 minute)
File 20180116 53314 45d63n.jpg?ixlib=rb 1.1
Some medications increase our risk of blood clots. And so does flying. www.shutterstock.com

Nial Wheate, University of Sydney

Every day, more than 10 million people take a flight somewhere in the world. While flying is relatively safe, the unique environmental conditions can put passengers at risk if they’re taking certain medications.

These include any hormone-based drugs, like the contraceptive pill and some fertility medicines, and drugs used to prevent heart attack and stroke. Antihistamines should also not be used to help passengers sleep during a flight.

Comentarii -

(Timp citire: 5 minute)
File 20180116 53310 18j2eki.jpg?ixlib=rb 1.1
With so many varieties, it’s hard to know which bread is the most nutritious. www.shutterstock.com

Leah Dowling, Swinburne University of Technology

Wholemeal, wholegrain, multigrain, sourdough, rye, white, high fibre white, low GI, low FODMAP, gluten free. With so many choices of bread available, how are we to know which is best for our health?

Bread has always been a dietary staple in Australian households. It’s a good source of carbohydrate, it’s low in fat, and wholegrain varieties are a good source of protein, fibre, vitamins and minerals, as well as healthy fats.

Wholegrains are high in dietary fibre, which helps keep us feeling full. Diets high in wholegrains are linked to a reduced risk of health conditions such as excess weight and obesity, heart disease, type 2 diabetes and some cancers. Dietary fibre is also beneficial for bowel health by preventing constipation and feeding the “good” gut bacteria which is likely to result in a number of health benefits. A recent study found a diet high in wholegrains was associated with a lower risk of bowel cancer.

Comentarii -

(Timp citire: 5 minute)

By Wendy Orent

We all know what Neanderthals looked like: the beetling brow ridges, thick nose, long skull, massive bone structure—and probably red hair and freckled skin. You might do a double take if you saw one on the subway, wearing a suit, or you might not. But you would surely look twice at the hunter-gatherers that populated Europe between 7,000 and 8,000 years ago, whose DNA scientists are analyzing now. They had dark skin and, very likely, bright blue eyes, like the beautiful child from Afghanistan you see in the photograph above. This combination essentially vanished from ancient Europe, replaced by light-skinned, brown-eyed farmers who moved in from the Middle East over the course of several centuries, and who looked like most of the population of southern Europe today.

Comentarii -

(Timp citire: 7 - 8 minute)
File 20170703 751 b3kd8o.jpg?ixlib=rb 1.1
Modern diets are changing the compositions of our gut microbiota, and with that, our personalities. from shutterstock.com

Amy Loughman, RMIT University and Tarsh Bates, University of Western Australia

We have long believed that “good” immune cells recognise and defend against “bad” invaders. That’s why a large proportion of medicine has been directed at killing microbial enemies and conquering microbial infections.

This militaristic understanding of immunity reflected the culture of the 20th century, which was dominated by nation building and world wars between “us” and “them.” It was a time when “survival of the fittest” came to be seen as the driver of evolution and competition and war were considered a natural part of what it is to be human.

But a radical shift in understanding the relationship between humans and microorganisms occurred with the discovery that only 50% of the cells in our bodies are human. The rest are microbes, such as bacteria, yeasts (members of the fungus family), viruses, and even insects. Together, these make up the microbiome.

Comentarii -

(Timp citire: 6 minute)
File 20180109 36019 q61srv.jpg?ixlib=rb 1.1
Influenza victims crowd into an emergency hospital near Fort Riley, Kansas in 1918. AP Photo/National Museum of Health

Richard Gunderman, Indiana University

This year marks the 100th anniversary of the great influenza pandemic of 1918. Between 50 and 100 million people are thought to have died, representing as much as 5 percent of the world’s population. Half a billion people were infected.

Especially remarkable was the 1918 flu’s predilection for taking the lives of otherwise healthy young adults, as opposed to children and the elderly, who usually suffer most. Some have called it the greatest pandemic in history.

The 1918 flu pandemic has been a regular subject of speculation over the last century. Historians and scientists have advanced numerous hypotheses regarding its origin, spread and consequences. As a result, many of us harbor misconceptions about it.

Comentarii -

(Timp citire: 6 - 7 minute)
File 20171212 9389 owdwfc.jpg?ixlib=rb 1.1
Cimex lectularius. CDC/Wikimedia

Romain Garrouste, Muséum national d’histoire naturelle (MNHN) – Sorbonne Universités

If some insects could save the world, others do their best to seriously complicate life on earth. Among them the prize perhaps goes to the bed bug, which after decades of absence has returned to our homes, hotels and public facilities to seriously disturb us.

These intrepid little insects aren’t picky about where they set up shop – luxury suites and hospitals, public housing and rich neighbourhoods are all equally attractive to them. Given that bed bugs like to hang out where people congregate in the largest numbers, however, they prefer the city over the country.

So why have bed bugs returned, why are they so successful and what solutions exist to help us get rid of them? And beyond our fears and phobias, what is the true impact of these little demons?

Comentarii -

(Timp citire: 3 minute)

For the first time ever, working muscle tissue was created from stem cells. Engineering muscle from non-muscle could open the door to a host of advanced treatment and research opportunities.

Comentarii -

(Timp citire: 6 - 7 minute)
File 20180102 26163 8mp710.jpg?ixlib=rb 1.1
The inventor at rest, with a Tesla coil (thanks to a double exposure). Dickenson V. Alley, Wellcome Collection, CC BY

Richard Gunderman, Indiana University

Match the following figures – Albert Einstein, Thomas Edison, Guglielmo Marconi, Alfred Nobel and Nikola Tesla – with these biographical facts:

  • Spoke eight languages
  • Produced the first motor that ran on AC current
  • Developed the underlying technology for wireless communication over long distances
  • Held approximately 300 patents
  • Claimed to have developed a “superweapon” that would end all war

The match for each, of course, is Tesla. Surprised? Most people have heard his name, but few know much about his place in modern science and technology.

Comentarii -

(Timp citire: 4 minute)
File 20180108 83563 8u4ver.jpg?ixlib=rb 1.1
Rural China sheds light on the role of witchcraft in society. Ruth Mace, Author provided

Ruth Mace, UCL

From medieval witch hunts in Europe to contemporary “witch doctors” in Tanzania, belief in witchcraft has existed across human societies throughout history. Anthropologists have long been fascinated by the phenomenon, but have struggled to study it with quantitative methods – our understanding of how and why it arises is therefore poor.

Comentarii -

(Timp citire: 5 - 6 minute)
File 20171124 21805 13d9gze.jpg?ixlib=rb 1.1
Augmented warrior. U.S. Army/Flickr, CC BY

Gérard Dubey, Télécom École de Management – Institut Mines-Télécom

What exactly do we mean by an “enhanced” human? When this possibility is brought up, what is generally being referred to is the addition of human and machine-based performances (expanding on the figure of the cyborg popularised by science fiction). But enhanced in relation to what? According to which reference values and criteria? How, for example, can happiness be measured? A good life? Sensations, like smells or touch which connect us to the world? How happy we feel when we are working? All these dimensions that make life worth living. We must be careful here not to give in to the magic of figures. A plus can hide a minus; something gained may conceal something lost. What is gained or lost, however, is difficult to identify as it is neither quantifiable nor measurable.

Comentarii -

(Timp citire: 9 minute)
File 20171219 27557 sri3mm.jpg?ixlib=rb 1.1
The story of where we come from evolves almost every year. Shutterstock/Eugenio Marongiu

Bernard Wood, George Washington University and Michael Westaway, Griffith University

The question of where we humans come from is one many people ask, and the answer is getting more complicated as new evidence is emerging all the time.

For most of recorded history humankind has been placed on a metaphorical, and sometimes literal, pedestal. Sure, modern humans were flesh and blood like other animals.

But they were regarded as being so special that in the Linnaean taxonomy that prevailed well into the second half of the 20th century they were given their own family, the Hominidae.

Comentarii -

(Timp citire: 5 - 6 minute)
File 20171215 17878 n888sm.jpg?ixlib=rb 1.1
Is it just surfing or is it signal processing? dozemode/Pixabay

Patrick Flandrin, ENS Lyon

The notion of “signal processing” might seem like something impenetrably complex, even to scientists. However, the fact is that most of them have already being doing it for a long time, albeit in an unconscious way. Acquiring, shaping and transforming data, cleaning it for the sake of improved analysis and extraction of useful information – all of this is what experimental science is about. And by adding ideas of modelling and algorithms, you can arrive at an ensemble of methods that constitutes a scientific discipline in its own right.

Comentarii -

(Timp citire: 4 minute)
File 20180105 26139 win2wr.jpg?ixlib=rb 1.1
Photographee.eu/Shutterstock.com

Daryl O'Connor, University of Leeds

When people experience stress, the adrenal glands that sit on top of the kidneys release a steroid hormone called cortisol. However, our latest study shows that people who have experienced high levels of trauma in childhood, and who have attempted suicide, tend to release less cortisol when put under stress. These findings build on our earlier work that showed that the stress response system may be “faulty” or “damaged” in people who have recently tried to take their own life.

Comentarii -