14 junho 2015
volnixshin: fear-the-magic: I don’t care who you are. I don’t care what you’re in to. If you don’t...
volnixshin: fear-the-magic: I don’t care who you are. I don’t care what you’re in to. If you don’t...
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Virus hiding in our genome protects early human embryos We...
Virus hiding in our genome protects early human embryos
We may owe our survival and complexity to a stowaway virus that springs to life in the very first cells of human embryos. Not only does the virus seem to protect embryos from other viruses, but it also assists genes when the groundwork is under way for the body plan of a new human.
The finding backs the controversial idea that viruses which took up residence in our DNA millions of years ago may be playing the role of puppet master, quietly influencing our existence and evolution. “We are creatures controlled by viruses,” says Luis Villarreal of the University of California at Irvine.
Retroviruses insert their genetic material into the cells of their human or animal host. At first, this causes disease and death. Over time, however, the host evolves resistance to the virus, allowing any DNA that has embedded itself into sperm or egg cells to be passed down to the next generation. The virus is now known as an endogenous retrovirus or ERV – a permanent fixture in the host’s genome.
Silent protector
About 9 per cent of our genome is thought to have come about this way. Until recently, these viral relics were largely dismissed as inactive “junk” that ceased to have any impact on their host many thousands of years ago. The discovery that HERVK, the most recent ERV to make itself at home in our DNA – probably around 200,000 years ago – is active in human embryos challenges that notion.
Joanna Wysocka and her colleagues at Stanford University in California made the unexpected find while they were analysing gene activity in 3-day-old human embryos, which are bundles of eight cells. Besides DNA from the parents, they found genetic material from HERVK. “The cells were full of viral protein products, some of which had assembled to form viral-like particles,” says Wysocka.
Further experiments revealed that the virus appears to produce a protein that prevents other viruses penetrating the embryo, suggesting it protects the embryo from dangerous circulating viruses, such as influenza. It also seems to play a crucial role in the genetic activity of the embryonic cells, helping to genetic instructions to the cellular protein factories.
Biological dark matter
Tantalisingly, the stowaway virus might even provide clues to what makes us different from chimpanzees and other non-human primates. Some researchers have previously argued that ERVs may play a key role in how species diverge from each other, by activating different body plans and gene networks that may give one individual an edge over other members of the species.
Wysocka’s work backs up this idea, says Patrick Forterre of the Pasteur Institute in Paris. “It shows that the protein products of a relatively ‘recent’ retrovirus integration are present very early on in the embryo, and could be involved in some critical developmental programmes.” The observation that ERVs could also protect the embryo against infection also makes a lot of sense, he says Forterre. “It’s as if retroviruses are competing with each other via their human host.”
Despite being ubiquitous, viruses are often called the dark matter of biology as their influence frequently goes unnoticed. If DNA is a jungle, then the viruses are the animals and plants that live and adapt within it, says Villarreal, who in 2001 showed that the presence of a viral gene is essential for the formation of the human placenta. “DNA is the habitat, and the viruses are the inhabitants,” he says. The most influential viruses are those, like HERVK, that have inserted themselves permanently into our DNA and can be passed on to the next generation.
These viruses have the genetic tools to refashion the hosts’ genes, influencing which are active and when, and with which other genes they interact. This means they have the ability to reshape the physical characteristics of their hosts, says Villarreal. “It’s a massive dynamic pool of colonising genomes.”
Journal reference: Nature, DOI: 10.1038/nature14308
FREE PADS AND TAMPONS
dan-the-llamaa: graventum: Hey all you lovely people who have periods, the world is starting to...
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sparequarter: ageofdestruction: the sun, photographed by sdo,...
the sun, photographed by sdo, 15th april 2015.
19 images over 5 hours. images inverted and colour palette applied in post.
image credit: nasa/sdo, aia/eve/hmi. animation: ageofdestruction.
IS THERE LIKE A WEBSITE THAT INSTANTLY POSTS DAILY SDO PHOTOS?
kind of! goddard spaceflight center, who operate sdo, have a page where you can see the latest image of the sun in each wavelength here.
there’s also a couple of ways you should be able to see moving images of the sun taken by sdo, but both of them seem a bit broken to me:
- the movie kiosk shows the latest couple of days of imagery - but it doesn’t always start, and the wavelength selector doesn’t work at all for me
- the data browser - if you can deal with the horrible date/time selector to choose a range, then pick a wavelength, make sure “choose format” is set to “browser display”, then hit submit, you can see the sun anytime between about an hour ago and may 2010 when sdo came online.
i don’t know if there’s anyone scraping sdo images and automatically running them through instagram filters, or whatever, but it sounds feasible.
hope this helps!
b.
agethebeakerblog: Here’s a quick profile of one of the strangest...
Here’s a quick profile of one of the strangest pets out there – the capybara.
- Native to South America, capybaras are the world’s largest rodent, weighing between 35 to 66 kg (77 to 146 lbs.)
- The animals are herbivores, feeding on grasses, aquatic plants, fruit, and tree bark.
- They’re coprophagous, which means they eat their own poop. Scientists think they do this to fortify gut bacteria and maximize vitamin intake from food. The animals have been noted to also regurgitate and re-chew food for the same reasons.
- Capybaras can run as fast as a horse, but spend lots of time in the water, too. The animals can remain submerged for up to five minutes and love wallowing in the mud.
- With teeth that constantly grow (meaning they chew a lot of stuff), and a detailed patchwork of state and federal regulations in place governing the ownership of exotic pets, it’s important you check your local laws before even considering taking one of these things into your home. (And then it’s still probably a bad idea.)
(Image Credits: Flickr Creative Commons: yoppy, Marie Hale / Source: Wikimedia Commons, “A descriptive account of capybara behaviour,” Animal Planet)
movie: whyshoulddothing: If you aren’t following movie.tumblr.com WHY THE FUCK NOT
movie: whyshoulddothing: If you aren’t following movie.tumblr.com WHY THE FUCK NOT
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twilii: paperangelsandplastichearts: erinfknleigh: nowyoukno: ...
Also Amazon has free kindle ebooks, just “purchase” them and read them on any device with the kindle app!
I noticed that on my phone.
Also if you sign up with BookBub they offer free books depending on the genres and categories you selected every day!
azurlei: longlivethesunqueen:astreana:dippednv8splash:mephistos-...
Does astreana know this?also also also, depending on your college, your .edu email address may be available to you indefinitely, even after you’re no longer there. I graduated in 2012, and I’m buried under massive pile of student loans, but at least my Prime is free!life saved thank you.
also available in the UK if you have a .ac.uk student email
pretty much why i love shopping on amazon
NO WTFFFFFF YAAAAAASSS
OMG!!!! Thank you!
Wut? That is so awesome!
transit of the sun by the moon, photographed by stereo b 24th...
transit of the sun by the moon, photographed by stereo b 24th february 2007.
this alignment of sun-moon-spacecraft was used to calibrate stereo b’s cameras.
38 images over 17 hours, arranged to keep the moon fixed in place. 2 more views of the same event.
image credit: nasa/stereo. animation: ageofdestruction.
age
The Mysterious Syndrome In Which Healthy People Can’t...
The Mysterious Syndrome In Which Healthy People Can’t Recall Their Past
The authors of a recent study published in Neuropsycholgia say they’ve identified a new syndrome characterized by the inability to re-live previous experiences. It sounds a lot like amnesia, but people with this rare condition are otherwise healthy and have no history of brain damage or psychological trauma.
Most of us have no difficulty transporting our thoughts back in time to recall an event. We remember such details as who we were with, what the weather was like, and what clothes we were wearing. This important capacity, called autobiographical re-experiencing, is what helps us construct our life narratives.
As reported in BPS Research Digest, however, this capacity eludes an extremely small minority of otherwise healthy people. Called Severely Deficient Autobiographical Memory (SDAM), the proposed syndrome describes an impaired ability to re-experience the past, particularly as it pertains to episodic — and especially visual — memories.
A team of cognitive scientists led by Brian Levine from the University of Toronto studied three individuals with the condition. It’s an excruciatingly small sample size, but the extent of the condition is not yet known. Each of these subjects are high functioning adults with steady jobs — yet they cannot recall and re-live past events from a first-person perspective. Their learning and memory abilities are otherwise normal, so long as tasks don’t require the use of episodic memory, i.e. a person’s unique memory of a specific event.
“Even though they can learn and recall information normally and hold down professional careers, they cannot re-experience the past with a vivid sense of personal reliving. It’s as if their past was experienced in the third person,” noted Levin in a statement.
To get by, individuals with SDAM rely on what the researchers call “intact non-recollective memory,” which can include rehearsed factual knowledge about themselves or others.
“There is a lot that we can accomplish with these skills, which are also part of normal memory function,” said Levine.
For the study, the three individuals were put through a series of tests to assess their intelligence, memory, and mental performance. Of interest to the researchers was the observation that all three subjects fared poorly on a task requiring them to draw a complex figure from memory — an important clue linking impaired visual memory with autobiographical memory.
BPS Digest explains more:
Compared to fifteen comparison participants (matched with the target participants for age and educational background), the impaired participants were able to provide significantly fewer autobiographical, first-person details from their teen and youth years. For more recent events, the impaired participants’ recall appeared more normal, but the researchers think this is due to a combination of conservative scoring (when in doubt the researchers scored reminisces as autobiographical in nature), and the participants having learned compensation strategies such as studying diaries and photos and substituting their lack of autobiographical memory for memory of facts and semantic detail.
From a subjective perspective, the impaired participants described their own memories of past events from both distant and more recent times as almost completely lacking a first-person perspective or involving any sense of “re-experiencing”. They also struggled to imagine future events, consistent with the idea that memory and future imagination involve shared mental processes.
Brain scans revealed no traces of brain damage or illness, but the right-sided hippocampus — an important area for memory — was slightly smaller in those with SDAM. The researchers are reluctant to refer to the newly described syndrome as a type of “developmental amnesia” which is characterized by a dramatic reduction in brain volume related to memory.
The researchers conclude their study by encouraging more research, while also describing some of the limitations to their work:
Our goal was to describe the SDAM cases׳ cognitive syndrome and associated neuroimaging findings in as much detail as possible in order to stimulate further research on the nature of individual differences in episodic [memory], yet the use of a small sample and a large number of statistical comparisons means the present findings should be interpreted cautiously. Moreover, there are many unanswered questions about SDAM. There is no evidence to support a neurological or psychiatric explanation for our findings. Although SDAM appears to be developmental in nature, neither the history nor the neuroimaging findings are consistent with a classic developmental amnesia syndrome.
Levine’s team says future research is needed to determine how variability in episodic memory influences social experiences, daily function, and quality of life.
"$25 DOLLAR reward will be paid for the detection of the cowardly thief, who is in the habit of..."
“$25 DOLLAR reward will be paid for the detection of the cowardly thief, who is in the habit of sneaking and creeping up to the door of No. 10, City Hall Place, and stealing the Sun newspaper from under the door. The above reward will be paid for the information left at the Sun office: and a regular roasting is promised the low, guilty, nigardly thief.”
- an advertisement posted in the New York Sun, Feb. 29, 1840
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- an advertisement posted in the New York Sun, Feb. 29, 1840
Hi Rhys :) I saw a couple weeks back that you went to America. I was just wondering how can you afford to do that at 19 years old?!
Hey, yeah that’s right I went to America to visit my wonderful, beautiful girlfriend. At the moment...
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Born in Italy, Charles Ponzi emigrated to America in 1903, where...
Born in Italy, Charles Ponzi emigrated to America in 1903, where he bounced in and out of prison for a few years. Eventually, he went to work in Boston, where he married and briefly attempted to live on the straight and narrow. But in 1918, Ponzi discovered a loophole that allowed him to profit from international reply coupons (IRCs), which could be bought in one country and exchanged for postage stamps in another. Ponzi realized that stamp prices were different around the world, meaning that IRCs from one country could be sold for a profit in another. He quickly formed a company to do just that, promising huge rewards to investors, who queued up to take advantage of the scheme.
In reality, there were nowhere near enough IRCs to keep up with demand. Ponzi was simply paying old investors with money from newer investors, while raking off just enough to keep himself living the high life. By the time his fraud was uncovered, his gullible investors had lost an estimated $20 million. Ponzi spent the rest of his life flitting from one job to the next, unable to stop scamming people. After twelve years in two state jails, he was deported to Italy where he embezzled money from a government job and offered 100 percent returns for investors in his autobiography. He used a job with a Brazilian airline to become a smuggler, but was again caught and eventually became a poor English teacher, living mostly off unemployment benefits. Ponzi died in a charity hospital in Rio de Janeiro in 1949, but his name lives on…and probably how he would have wanted it to.
June 14th 1928: Che Guevara bornOn this day in 1928,...
Che Guevara (1928 - 1967)
Fulgencio Batista (1901 - 1973)
Fidel Castro with Che Guevara
June 14th 1928: Che Guevara born
On this day in 1928, revolutionary Che Guevara was born in Rosario, Argentina. Born Ernesto Guevara de la Serna, he studied medicine at university in Buenos Aires, and soon became interested in the work of Karl Marx. Guevara travelled widely, and became horrified at the extreme levels of poverty he witnessed, which led him to call for armed revolution. In 1955 he met Cuban revolutionary Fidel Castro, and the two became leading figures in the successful overthrow of Cuban dictator Fulgencio Batista. For his role in the revolution, Prime Minister Castro appointed Guevara high in the Cuban government, which allowed him to pursue policies like land redistribution. His revolutionary fervour did not end with Cuba, however, and in the 1960s Guevara continued to support guerrilla movements in Africa and South America. Inspired by Marxist doctrine, Guevara intended to begin a global revolution to topple the oppressive forces of colonialism and capitalism. In Bolivia, his efforts to aid revolutionaries led to his capture by the Bolivian army, who had the support of the CIA. On October 9th 1967, Che Guevara was executed by army forces.
Updated Science: Using All Your Senses
WE’VE BEEN DOING THIS SINCE 2013 AND IT FEELS SO GOOD, WHO CARES THAT IT’S SPINNING, THE WORLD IS SPINNING, THE INSIDE OF OUR NOSES ARE ALL BEAUTIFUL, LIKE COLORFUL DISHES.
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