amistad

"Covid-19 Changed How the World Does Science, Together”

"Never before, scientists say, have so many of the world’s researchers focused so urgently on one topic. Nearly all other research has ground to a halt.(...)”                              (Lido em: NYT 2020-04-01)

“Les secrets du cerveau d’Einstein”

“La mémoire est profondément liée à notre identité. Elle est aussi un des principaux enjeux du vieillissement. Et directement en lien avec nos capacités cognitives.

En lisant ce dossier spécial, vous découvrirez comment le cerveau d’Albert Einstein a permis de faire la lumière sur le fonctionnement de notre cerveau et de notre mémoire. Vous découvrirez notamment:

• Les différents types de mémoires

• Ce qui fait que nos souvenirs ne s’envolent pas

• Quels sont les pires ennemis de la mémoire

• Comment entretenir et optimiser vos capacités cognitives(...)”

• (Lido em: Le Monde 2020-03-01)

“A new breed of encryption algorithms that quantum computers can’t yet beat”

“Author Gemma Milne”

“As the race to build quantum computers heats up, the cybersecurity industry looks to the planet’s best mathematicians to protect the world’s information.

With the quest to build a full-scale quantum computer now expanding beyond the science lab to encompass technology giants (such as IBM, Google, Microsoft) and quantum computing start-ups (including Rigetti, IonQ and 1Qubit), the race is on to create the hardware and software powering the next generation of computation.(...)”           (Lido em: CNNNews 2019-11-08)

“«L’être humain ne meurt pas d’un seul coup»: comment définir l’instant précis où la vie s’arrête?”

“Par Pascale Santi et Pierre Lepidi”

“EnquêteAu moment de la mort, les organes s’éteignent à des rythmes différents. Comment, dans ces conditions, définir l’instant précis où la vie s’arrête ? En explorant plusieurs pistes, dont l’activité du cerveau, des chercheurs tentent de donner une réponse à cette question hautement symbolique.

Mystérieuse, universelle et taboue, la mort fascine. Mais la relation que les hommes entretiennent avec elle diffère selon les cultures ou les religions. Suivant la tradition catholique, les vivants rendront hommage à leurs défunts samedi 2 novembre. En France et plus généralement en Europe, ils fleuriront leurs tombes ou se recueilleront chez eux, parfois en allumant une bougie. Au Guatemala ou ailleurs en Amérique latine, les célébrations seront plus festives, et c’est au rythme des mariachis que les croyants entreront dans les cimetières.

On ne peut définir la mort que par rapport à la vie. Selon le dictionnaire Larousse, elle est la « perte définitive par une entité vivante (organe, individu, tissu ou cellule) des propriétés caractéristiques de la vie, entraînant sa destruction ». Par définition, on devient donc mort lorsqu’on n’est plus vivant. « On peut bien sûr considérer que la mort est la fin de la vie, mais alors qu’est-ce que la vie ?, s’interroge Benjamin Rohaut, neurologue à la Pitié-Salpêtrière (AP-HP-Sorbonne Université). Est-on vivant seulement lorsqu’on est conscient ? Lorsqu’on a une activité cérébrale ? Lorsque son cœur bat ? Définir la mort, c’est définir la vie, et on peut alors se heurter à des impasses conceptuelles. C’est certainement une des raisons qui font que la mort a une définition légale. »

Evolution du concept de mort

Jusque dans les années 1950, la mort était définie par l’arrêt des fonctions vitales (le cœur, la respiration). Puis le respirateur artificiel, inventé en 1952 par le médecin danois Bjorn Ibsen, a révolutionné la médecine, en donnant naissance à la réanimation et aux soins intensifs. Cette invention a fait évoluer le concept de mort, sans cesse débattu. Ce sont les médecins français Maurice Goulon et Pierre Mollaret qui ont décrit en 1959 la notion de « coma dépassé », ou mort cérébrale, (...)”

(Lido em: Le Monde, 2019-11-01)

“In the Pancreas, Common Fungi May Drive Cancer”

“By Knvul Sheikh”

“A new study found that certain fungi can settle in the pancreas, where they spur the growth of tumors.

The abundance in the pancreas of the yeast Malassezia, more commonly found on the skin of humans and animals, surprised the scientists.CreditCreditScience Source

• By now, you’ve probably heard that your body is teeming with bacteria. Some 100 trillion of them live on your skin, in your mouth and in the coils of your intestines. Some protect against infections and help you digest food, while others can make you seriously ill.

Fungi, viruses and protozoa call your body their home, too. Your fungal residents are less numerous than your bacteria by orders of magnitude, but as researchers are learning, these overlooked organisms play an important physiological role — and when their numbers get out of whack, they can modify your immune system and even influence the development of cancer.(...)”

(Lido em: The New York Times 2019-10-04)

“Scientists discover a worm that has three sexes and a pouch like a kangaroo's”

“This new species of worm could clue scientists in on how humans can withstand high levels of arsenic, according to a new study.

"There's a new species of worm, and this one has three different sexes, can survive 500 times the dose of arsenic it would take to kill a human and keeps its young in a pouch, not unlike a kangaroo.

Researchers think humans might have something to learn from the worm's resilience.

Caltech researchers discovered eight species of worms that live in the arsenic-rich Mono Lake in California. The team published its findings Thursday in the journal Current Biology.(...)”

(Lido em: CNNnews 2019-09-27)

hoje é o 250º aniversário de alexander von humboldt

“250 Anniversary Alexander von Humboldt”

“Scientist, cosmopolitan and explorer”

“Alexander von Humboldt is still one of the best-known Germans internationally. As a cosmopolitan, a universal scholar, Alexander von Humboldt was influenced by the Enlightenment and cultivated a global exchange and a network of friendships. Humboldt is considered a co-founder of geography and the second discoverer of South America.
Alexander von Humboldt dealt with botany, ethnology and cartography, meteorology and agriculture. The Humboldt Forum opens for the anniversary. The opening is flanked in the run-up by events that deal with his work and his impact up to the present day. Here we offer a selection.(...)” (Lido no Google, 2019-09-14))

“250 years young! Celebrating Alexander von Humboldt’s birthday”

“The Humboldt Forum is set to celebrate Alexander von Humboldt’s 250th birthday on 13 and 14 September 2019 in an event featuring contributions from Bogotá, Lima, London, Mexico City, Novosibirsk, Potsdam, Quito and Berlin.(...)” (Lido no Google 2019-09-14)

“Lovers of Modena skeletons holding hands were both men”

“The skeletons, buried in Roman times, have been holding hands for around 1,500 years

Researchers have found that a couple of skeletons known as the Lovers of Modena, because they are holding hands, were both men.

The researchers could not determine the sex of the skeletons when they were found in Italy in 2011 because they were badly preserved.

But a new technique, using the protein on tooth enamel, revealed their sex.

The actual relationship between the skeletons from the 4-6th Century AD remains a mystery.

But the researchers from Italy's University of Bologna said in Nature research journal that the findings have profound implications for understanding funeral practices at that time in Italy.(...)”

(Lido em: BBCNews, 2019-09-12)

“The 'unwarranted hype' of stem cell therapies”

“By Jules Montague”

“Clinics claim that expensive stem cell therapies can help patients with dementia, autism, multiple sclerosis and even cerebral palsy - and crowdfunding campaigns to pay for the treatments are increasingly common. But are the patients and the donors being misled about the benefits and the risks?

“Jay Shetty is 8 years old. He is smart and bright, says his mother Shilpa, even if he can’t do all the things his younger brother can. “Jay doesn’t sit up or use his hands much. He’s non-verbal and we don’t know how well he can see,” she says. “But he plays with us and tries to copy everything his younger brother Kairav does.”

Jay has cerebral palsy. In his early years, Shilpa was desperate to find anything that might help him. Scouring the internet late each night, she read about a stem cell trial at Duke University in North Carolina but Jay wasn’t eligible. When Kairav was born in 2015, Shilpa and her husband stored their younger son’s umbilical cord

blood, which was rich in blood stem cells, hoping another trial would emerge. It did, and this time, children with sibling cord blood could participate. Was she worried about the risks for Jay? “It wasn’t invasive and it couldn’t do any harm really.” To raise the £15,000 ($18,200) treatment bill, they supplemented money they had already fundraised for private physiotherapy and hydrotherapy with a personal loan and a further fundraising push supported by the cord bank where Kairav’s cord blood had been stored.

Cerebral palsy is a group of lifelong conditions that affect movement and coordination. In Jay’s case, Shilpa explains, there were complications around the time of his birth that led to the condition. There is no cure for cerebral palsy but physiotherapy, speech therapy and occupational therapy can help some symptoms. Shilpa hoped, though, that Jay’s stem cell therapy – a two-hour infusion into his veins – would bring benefits far beyond everything they had tried before. (...)”               (Lido em: BBCnews 2019-08-21)

“What happens to a body donated to science?”

“A man who donated his mother's body to what he thought was Alzheimer's research learned later it was used to test explosives. So what does happen when your body is donated to medical science?

Last week new details of a lawsuit emerged against The Biological Resource Centre in Arizona following an FBI raid in 2014 in which gruesome remains of hundreds of discarded body parts were discovered.

The now closed centre is accused of illegally selling body parts against the donors wishes. (...)” (Lido em: BBCNews 2019-08-07)