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Animal species comes back to life after 24,000 years in permafrost

The microscopic animal, called the bdelloid rotifer, survived in the Siberian permafrost for 24,000 years before resuming a normal life.

The scenario of this cryonics is worthy of a science fiction film. A team of scientists from the Soil Cryology Laboratory in Russia studied a microscopic animal species, the bdelloid, which survived in permafrost in Siberia for 24,000 years, reveals a study published on June 7, 2021 in the American scientific journal of cell biology Current Biology .

A species capable of putting its metabolism on hold for several thousand years

Taken 3.6 meters below the surface near the Alazeia River in northeastern Siberia, the bdelloids were brought to the surface for observation.

After thawing, the animal, about half a millimeter long, usually living in freshwater, came back to life. In a video published in the scientific journal, we can observe, thanks to a microscope, the bdelloïde move.

He was able to reproduce asexually using a self-cloning process called parthenogenesis and also began to eat normally.

The biological ability to put one’s life on hold for a long period in a frozen state raises many questions for scientists. « Our report is the strongest evidence to date that multicellular animals could endure tens of thousands of years in cryptobiosis, a state in which the metabolism is almost completely at a standstill, » said Stas Malavin, co-author of the study and member of the Institute of Physicochemical and Biological Soil Problems in Pouchtchino (Russia).

This discovery in permafrost adds rotifers to the list of multicellular organisms capable of surviving indefinitely.  » The bottom line is that a multicellular organism can be frozen and stored as such for thousands of years and then come back to life, a dream shared by many writers of fiction, » concludes Stas Malavin. .

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Billionaire Jeff Bezos to participate in Blue Origin’s 1st space tourism trip

The wealthy businessman, boss of Amazon, announced on Monday that he would participate in the 1st space tourism trip organized by his own company, Blue Origin

It’s official ! The American Jeff Bezos, wealthy boss of Amazon, revealed on Monday that he would participate in the first space tourist trip organized by his company Blue Origin, created with the aim of lowering the costs of access to space in 2000 Accompanied by his brother Mark and the winner of an auction, he will set off in the space aboard the New Shepard capsule.

“Since I was five years old, I have dreamed of traveling in space. On July 20, I will be making this trip with my brother. The greatest adventure, with my best friend, ”wrote the billionaire in a post on his Instagram account.

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Why is there no vaccine against HIV when a year was enough to develop several against Covid-19?

In less than a year, several vaccines against Covid-19 have been created. Conversely, forty years after the discovery of the AIDS virus, there is none against the disease. people with HIV are forced to take treatment for life. How to explain such a discrepancy?

For decades, researchers have been trying to find a vaccine against HIV, but it is particularly complex for three main reasons:

1.There are several subtypes of HIV circulating in the world

The  big difficulty with HIV is the presence of many variants . Beside, those  of the coronavirus , or even the flu, look pale. « If you compare it to a virus like influenza, which is so variable that the vaccine  can never eliminate all of its forms , the number of mutations globally is the number of variations in HIV in a single individual. 

While HIV is highly variable, and unlike any other, the coronavirus family has been known for many years. The  SARS  and  MERS epidemics  in 2002 and 2013 also accelerated research on the subject. 

2. The virus mutates enormously

In the most recent PloS Biology, Cuevas and colleagues quantify the HIV-1 genome-wide rate of spontaneous mutation in DNA sequences from peripheral blood mononuclear cells. They reveal a mutation rate 4 × 10−3 per base per cell, which is the highest reported mutation rate for any biological entity. When they sequenced plasma-derived HIV-1, they found the mutation rate was 44 times lower: “indicating that a large fraction of viral genomes are lethally mutated and fail to reach plasma.” Most interestingly, the authors showed that the viral reverse transcriptase accounts for only 2% of mutations, with the remaining 98% of viral genetic variation a result from editing by host cytidine deaminases.

3.HIV integrates into the genome of the infected person and persists.

Conversely, the vaccine against Covid-19 presents fewer difficulties . « The coronavirus is not a virus that integrates into the genome. We have most people who manage to eliminate it with their natural immune system

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China allows a third child: 3 questions to understand the stakes for the country

Faced with the challenge of the aging of its population, China is taking another step towards liberalizing its birth rate and authorizing a third child. But not sure that Chinese women are flocking to maternity hospitals.

The  China  is still  the most populous country in the world  with 1,412 billion

The  China  is still  the most populous country in the world  with 1,412 billion. But its population is only increasing by 0.53% per year. And above all, the thirty-five years of the one-child policy, from 1979-1980 to 2015, profoundly modified its age pyramid. The objective of improving the standard of living of the population, aimed at by its initiators, has been achieved. But now that the “only children” are of parentage age, and their parents of retirement age, there is a big problem.

1. What is the problem for China?

The ageing of the population. The economic cost of its support in relation to the working population is mathematically unbalanced by the one-child policy. Each single child, now an adult, bears the burden of supporting both parents on their shoulders alone.

2. What was the impact of the authorization to pass to two children in 2015?

Apart from a weak rebound just after the announcement, this first authorization had no effect. The number of births resumed its fall in 2016 to fall to twelve million in 2020 against 14.65 million in 2019. That year, the birth rate had already hit a low since the founding of Communist China in 1949.

4. Is this authorization likely to be a game-changer?

Not really if taken alone. The low enthusiasm for the second child in urban and affluent circles since 2015 has shown that the authorities’ green light alone will not have a magical effect. Additional announcements are expected on social support for childcare, maternity leave, the cost of their education, etc.

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La Chine autorise un troisième enfant : 3 questions pour comprendre les enjeux pour le pays

La Chine est toujours le pays le plus peuplé du monde avec 1,412 milliard d’habitants

Face au défi du vieillissement de sa population, la Chine fait un pas de plus vers la libéralisation de sa natalité et autorise un troisième enfant. Mais pas sûr que les Chinoises se ruent vers les maternités.

La Chine est toujours le pays le plus peuplé du monde avec 1,412 milliard d’habitants. Mais sa population n’augmente plus que de 0,53 % par an. Et surtout, les trente-cinq années de politique de l’enfant unique, de 1979-1980 à 2015, ont profondément modifié sa pyramide des âges. L’objectif d’amélioration du niveau de vie de la population, visé par ses initiateurs, a bien été atteint. Mais à présent que les « enfants uniques » sont en âge d’être parents, et leurs parents en âge d’être à la retraite, se pose un gros problème.

1. Quel est le problème pour la Chine ?

Le vieillissement de la population. Le coût économique de sa prise en charge rapporté à la population active, est mathématiquement déséquilibré par la politique de l’enfant unique. Chaque enfant unique désormais adulte a sur ses seules épaules le poids de la prise en charge de ses deux parents.

2. Quel a été l’impact de l’autorisation de passer à deux enfants en 2015 ?

En dehors d’un faible rebond juste après l’annonce, cette première autorisation n’a pas eu d’effet. Le nombre de naissances a repris sa chute dès 2016 pour tomber à douze millions en 2020 contre 14,65 millions en 2019. Cette année-là, le taux de natalité avait déjà touché un plus bas depuis la fondation de la Chine communiste en 1949.

4. Cette autorisation a-t-elle des chances de changer la donne ?

Pas vraiment si elle est prise seule. Le faible engouement pour le deuxième enfant dans les milieux citadins et aisés depuis 2015 a montré que le seul feu vert des autorités n’aura pas d’effet magique. Des annonces complémentaires sont attendues sur la prise en charge sociale de la garde d’enfant, les congés maternité, le coût de leur éducation…

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What is the maximum lifespan of a human being? New study takes stock

According to a study, the maximum lifespan of a human being is between 120 and 150 years. Nothing could prevent this inevitable aging

Is this the end of the myth of the immortal man? The age of death cannot be pushed back indefinitely, according to a study on aging by researcher Andrei Gudkov, co-founder of Genome Protection, a biotechnology company specializing in anti-aging therapies.

It’s all about resilience

Death would therefore be inevitable, due to “the gradual loss of resilience” according to the study, that is to say the ability to recover after “stress”. At 40, humans take two weeks to recover. At 80, it takes six weeks. According to the study, between 120 and 150 years, the human being would completely lose his capacity for resilience and therefore could no longer recover from various diseases.

“This explains why even the most effective prevention and treatment of these diseases could only improve the average lifespan, but not the maximum lifespan, unless true anti-aging therapies are developed”, describes the ‘study. Which could raise many ethical questions.

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Ligue des champions: Chelsea s’offre un deuxième sacre en battant Manchester City

La finale de la Ligue des champions, jouée à Porto samedi 29 mai, a vu Chelsea l’emporter face à Manchester City (1-0) au stade du Dragon. Le milieu de terrain Kai Havertz a inscrit le but victorieux des Blues, qui soulèvent la Coupe aux grandes oreilles pour la seconde fois après celle de 2012. Les Cityzens de Guardiola, trop timorés, voient leur rêve s’envoler.

La malédiction se poursuit. Comme Paris l’année passée, Arsenal ou encore Chelsea en son temps, Manchester City n’a pas réussi à s’imposer par la première finale de Ligue des champions de son histoire. Les champions d’Angleterre voulaient plus que tout l’emporter samedi et imiter le Borussia Dortmund de 1997 (vainqueur de la Juventus 3-1 pour sa première finale de C1). Le sort, le match et Chelsea en ont décidé autrement.

Pour cette finale délocalisée au Portugal, les tribunes du stade du Dragon de Porto étaient un peu garnies. Malgré la pandémie de Covid-19, les instances ont autorisé la présence de 14 000 spectateurs britanniques, dépistés ou vaccinés. Un grand match avec des supporters pour mettre de l’ambiance, cela faisait plus d’un an que l’on n’avait plus vu ça en Ligue des champions.

Champion d’Angleterre et vainqueur de la League Cup, Manchester City avait l’occasion de réaliser le triplé. Pep Guardiola a aligné d’entrée son meilleur onze, avec bien sûr son capitaine et maître à jouer Kevin De Bruyne à la baguette. Mais c’est Chelsea qui est le mieux entré dans cette finale.

Chelsea ajoute une deuxième Ligue des champions à son palmarès, après celle de 2012. Pour Thomas Tuchel, battu en août dernier avec le PSG par le Bayern Munich en finale de la précédente édition, puis débarqué par le club parisien fin 2020, ce sacre est sans doute savoureux. Manchester City, malgré les investissements colossaux de son propriétaire d’Abou Dhabi depuis 2008, repart triste, frustré et bredouille. La Ligue des champions est un Graal décidément bien difficile à obtenir.


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Do you have « blood in gold »? The rarest blood group on the planet!

One of the rarest blood groups in the world is Rh-null, sometimes referred to as ‘blood of gold’. But why this nickname and what sets it apart from other bands?

You may already know your blood type. In fact, the classification of blood as we know it today is the result of work conducted by the Austrian physician Karl Landsteiner in the early 20 th century. Before that, our ancestors had developed various theories about blood .

For example, 17th century physicians considered blood to be part of a set of four bodily fluids or « humors » – the other three being black bile, yellow bile, and phlegm. Ancient Greek physicians claimed that these fluids determined someone’s personality. Also, the greater the volume of blood circulating in a person’s body, the more he or she would be passionate, charismatic and impulsive.

The blood type depends on the nature of the red blood cells

It wasn’t until 1628, when William Harvey discovered the way blood circulates in our bodies, that the era of modern hematology began. In any case, it took some time to understand the subtlety of this vital biological substance which is continually circulating in the blood vessels and in the heart.

As a reminder, blood is made up of red blood cells , white blood cells, platelets and plasma. Each component plays an important role, but blood rankings are based on red blood cells. These contain proteins called antigens.

Important subdivisions

The presence or absence of particular antigens determines the blood group . So, type A blood has only A antigens, type B only B, and type AB has both. Note that type O blood does not carry antigen. Red blood cells carry another antigen known as the RhD protein .

When present, a blood group is said to be positive. When it is absent, we say that it is negative. These combinations are the source of the eight common blood groups , namely, A +, A-, B +, B-, AB +, AB-, O + and O-. Each of these eight types can be subdivided into many distinct varieties, and the RhD protein just discussed only refers to one of 61 potential Rh system proteins.

Rh-null, an extremely rare blood group

Blood is said to be Rh-null when it does not contain all the antigens of said system. This extremely rare blood group was first identified in 1961 in an Australian aboriginal. Since then, scientists have only identified around forty people from the same group around the world, hence the name “blood in gold”.Very few donors and therefore a risk for people with this blood type. Photo credit: Shutterstock / Jora Abramov

This means that Rh-null blood donations are incredibly rare. And when an Rh-null individual needs a blood transfusion, it can be very difficult to find a donor . For this reason, Rh-null people are encouraged to donate blood as insurance for themselves.

In short, living with this blood type can be considered a privilege since the carrier is generally a « universal donor », but it also constitutes a danger. As the Smithsonian  website explains, “there are less than 10 active Rh-null blood donors in the world. This means that injuries represent a major risk (…), but it also means that it has the power to save lives (…) However, international donations are often hampered by bureaucracy. « 

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What is the full ranking of Eurovision 2021

The Contest Eurovision Song 2021 is the 65 th edition of the competition. Is an annual event organized by the European Union of Broadcasting, the EBU. It brings together the members of the Union within the framework of a musical competition, broadcast live and simultaneously by all the participating broadcasters.

1. Italy (524 points)
2. France (499 points)
3. Switzerland (432 points)
4. Iceland (378 points)
5. Ukraine (364 points)
6. Finland (301 points)
7. Malta (255 points)
8. Lithuania (220 points)
9. Russia (204 points)
10. Greece (170 points)
11.Bulgaria (170 points)
12. Portugal (153 points)
13. Moldova (115 points)
14. Sweden (109 points)
15. Serbia (102 points)
16. Cyprus (94 points)
17. Israel (93 points)
18. Norway (75 points)
19. Belgium (74 points)
20. Azerbaijan (65 points)
21 . Albania (57 points)
22. San Marino (50 points)
23. The Netherlands (11 points)
24. Spain (6 points)
25. Germany (3 points)
26. the United Kingdom (0 points)

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How many birds are there on earth?

An unprecedented study counts the total and current number of individuals from all known bird species.

You have inevitably already wondered how many individuals of the same species exist on the planet, while being seized with a vertigo of curiosity at this moment. Scientists at an Australian university have produced just one of the most massive studies to date. In the journal Proceedings of the National Academy of Sciences , they published, in May 2021, their calculations on the abundance of birds.

They therefore answer this question: how many wild birds are there currently on the planet?

At least 50 billion. That’s according to a study published this month in the journal Proceedings of the National Academy of Sciences . Conducted by Australian researchers, this work was notably based on millions of observations posted by « citizen scientists » on the eBird site .

 » Humans have gone to considerable effort to enumerate the members of our own species – the 7.8 billion of us. This marks the first global effort to count a collection of other species,  » said Will Cornwell, ecologist at the University of New South Wales and co-author of the study.

The figure of 50 billion birds, however, only reflects a very small part of reality. Because only four species exceed one billion individuals; house sparrow ( Passer domesticus:  1.6 billion), starling ( Sturnus vulgaris:  1.3 billion), ring- billed gull ( Larus delawarensis:  1.2 billion) and barn swallow ( Hirundo rustica:  1.1 billion). Conversely, 1,180 species of birds, or 12% of the total, each account for less than 5,000 specimens; a species numbering less than 2,500 individuals being considered endangered by the International Union for the Conservation of Nature ( IUCN ).

Like other animals, birds are in sharp decline across the world. In 2018, a study carried out by the NGO Bird Life International concluded that at least 40% of species are experiencing a decline in their population. In 2017, nearly 1,500 were considered threatened. In 1997, a study estimated the number of birds on Earth (or rather in the air !) Between 200 and 400 billion.