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Relu Dumitru
Lived in Timisoara, Romania
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Maybe that's why we spend twice as much on healthcare and live shorter lives than other countries :)


VEGANISM

For 100+ reasons I didn't eat meat for 20 years and dairy for 12 years seehttps://plus.google.com/+AlexP/posts/EkQQAE68fCm (12% of millennials gave up meat already in America). Going vegan is like planting 62 trees in your backyard, as far as CO2 emissions reduction.
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The Evolution of Antibiotic Resistance

One of my favourite things about my job at the MRC is writing about all types of biomedical research, and not just cancer. This week I’ve been digging into the threat of antibiotic resistance, and it is truly sobering to read how bad a problem it is. Coincidentally I stumbled across this fantastic experiment carried out by a team of researchers at Harvard University. It illustrates how antibiotic resistance happens, and more importantly (and scarily!) how fast it happens. I love this experiment for the simplicity behind it, and how illuminating the results are.

✤ To study the evolution of antibiotic resistance, the researchers set up a giant petri dish. This rectangular dish was filled with agar that was dyed black (so that the bacteria could be seen easily) and topped off with soft agar (so that the bacteria could move easily).

✤ The plate was divided up into nine sections for antibiotic concentration. The outmost edges of the plate had no antibiotic, and then the dose was gradually increased until the centre of the plate had 3000 units of antibiotic.

✤ The researchers then put E. coli bacteria on the edge of the plate. These bacteria are able to move, and therefore when they used up all the nutrients in a local area, they spread through a mechanism called ‘chemotaxis’ – the bacteria are drawn towards the chemicals released by the nutrients in the nearby regions on the agar plate. But these nearby regions have antibiotics in them, so only bacteria that have evolved resistance can spread to these regions.

✤ It’s worth noting that the antibiotic starts out at a non-lethal dose, which means that a certain proportion of the bacteria will be able to survive it. Then, as the antibiotic gradually increases, it selects the bacteria that have mutations in their genes that allow them to survive despite ever-increasing concentrations of antibiotic.

✤ The beauty of this experiment is that it is possible to see this happening in the relatively short space of 11 days. What’s more, the researchers were able to sample the resistant bacteria and then sequence the genes to find out exactly how antibiotic resistance evolves.

✤ One of the most common mutations was in a gene known as dnaQ which codes for a protein that helps copy DNA when the cells divide. This protein has proof-reading abilities, but when it is mutated, the proof-reading ‘relaxes’ - resulting in a typo-ridden genome that has immense potential for accumulating more and more mutations very rapidly. In addition to dnaQ mutations, the bacteria also had mutations in genes involved in the folate biosynthesis pathway, which is the main target of the antibiotic used in this experiment.

✤ It’s also worth noting that mutations that increased antibiotic resistance came at a cost – these mutant bacterial strains were smaller due to reduced growth. But as soon as the mutants established themselves in the antibiotic-filled region, compensatory mutations kicked in and they were able to reach normal size.

✤ In the end, the bacteria at the centre of the plate were able to tolerate a dose of antibiotics that was 1000 times higher than that tolerated by the starting bacteria. It’s terrifying to realise how under the right conditions, bacteria can evolve so quickly. It’s also sobering to realise that antibiotics, a discovery that transformed modern medicine, may soon be obsolete thanks to the wide-spread misuse of antibiotics in agriculture and medical settings.

Full text research paper: http://science.sciencemag.org/content/353/6304/1147.full

More writing on antibiotic resistance: https://www.statnews.com/2016/09/12/superbug-antibiotic-resistance-history/ and http://phenomena.nationalgeographic.com/2015/11/21/mcr-gene-colistin/
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Reconstruction of ancient Jericho as it looked around 1550 BC, just before the Bronze Age city had been destroyed. [[MORE]]Jericho was continually occupied into the Middle Bronze Age; it was destroyed...
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La nature perd peu à peu du terrain face à l'homme. D'après un article paru cette semaine dans la revue scientifique Current Biology, les terres...
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Marcelina Lancaster of PNB SI by Francisco Estevez (2016)
http://bit.ly/2cK5pLv
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Is your university on the list?
A new report has found that nearly a quarter of Europe’s most innovative universities are in Germany.
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CHAPTER II. MEHADIA. ON board the steamer was a young officer going to Mehadia-or Hercules' Bath, as the place is called,-so we drove thither together. The road at first runs through a broad wooded valley, but afterwards, as it turns off to the right, grows narrower, and there are occasionally ...
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The World Nomad Games, Kyrgyzstan. 
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An even bigger particle accelerator?

This is Chen-Ning Yang.  He helped create Yang-Mills theory - the wonderful theory that describes all the forces in nature except gravity.    He helped find the Yang-Baxter equations, which describe what particles do when they move around on a thin sheet of matter, tracing out braids. 

He's one of China's top particle physicists... and he's come out against  building a new, bigger particle accelerator!   This is a big deal, because only China has the will to pay for the next machine.

In 2012, two months after the Large Hadron Collider (near Geneva) found the Higgs boson, a Chinese institute called for a bigger machine: the Circular Electron Positron Collider or CEPC.

This machine would be a ring 80 kilometers around.  It would collide electrons and positrons at an energy of 250 GeV, about twice what you need to make a Higgs.   It could make lots of Higgs bosons and study their properties.  It might find something new, too!  Of course that would be the hope.

It would cost $6 billion, and the plan was that China would pay for 70% of it.  Nobody knows who would pay for the rest.

On 4 September, Yang, in an article posted on the social media platform WeChat, says that China should not build a supercollider now. He is concerned about the huge cost and says the money would be better spent on pressing societal needs. In addition, he does not believe the science justifies the cost: The LHC confirmed the existence of the Higgs boson, he notes, but it has not discovered new particles or inconsistencies in the standard model of particle physics. The prospect of an even bigger collider succeeding where the LHC has failed is “a guess on top of a guess,” he writes. Yang argues that high-energy physicists should eschew big accelerator projects for now and start blazing trails in new experimental and theoretical approaches.

That same day, the director of the institute that wants to build the machine posted a rebuttal on WeChat.   I can't read it, because it's in Chinese:

http://chuansong.me/n/680325551051

It will be interesting to see how this plays out.  Personally I think we as a species need to focus on global warming and the Anthropocene: the way we're transforming the Earth. 

In the last 25 years, 10% of the world's remaining wilderness has disappeared.   Temperatures are rising at an ever-increasing rate.   If we keep it up, we'll melt Greenland and the Antarctic, eventually flooding all coastal cities.  Even now, weather patterns are changing, with big heat waves, floods and droughts becoming more common. 

Surviving the Anthropocene will require new math, new physics, new chemistry, new biology, new computer science, and new technology of many kinds.  Most of all, it will require new attitudes - new politics and economics.

One thing that won't  be required is new elementary particles.  I love fundamental physics.   But finding new particles can wait.  They'll still be here in a century or two.  Our civilization, and the natural world we love, may not.

What really matters here is not the money.  $6 billion is not much in the grand scheme of things.  For example, this fall California is voting on a $9 billion bond measure for its schools.    What really matters is where scientists put their energy

The quote is from Science magazine:

http://www.sciencemag.org/news/2016/09/debate-signals-cloudy-outlook-chinese-supercollider

The Earth's disappearing wilderness:

https://www.theguardian.com/environment/2016/sep/08/humans-have-destroyed-a-tenth-of-earths-wilderness-in-25-years-study

xkcd has a great graph of the Earth's temperature - check it out!  You'll learn a lot and have fun:

http://xkcd.com/1732/

#physics  
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🍃Gustav Klimt🍃
La fanciulla che dorme 🍃
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scaleber force [Explored]
Photo by bojangles_1953 on Flickr...
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Skeptic.
Believing that Life is the most improbable thing in the Universe (statistically speaking).
Thats why LIFE is the most valuable thing in the Universe.


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În ce mă privește pot spune că dacă vreți să beți o cafea bună, să vă aduceți de acasă. Cafeneaua "Bună ziua" n-are nici o legătură cu cafeaua. Dar are terasă, așa că barem puteți lua un suc la țigară. În nici un caz cafea.... Să aveți noroc !
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Patru angajați se fîțîie degeaba, un angajat încasează. Coadă ca pe vremuri. A doua casierie - Off. Asta-nseamnă NESIMTIRE (și prostie) cu carul.
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Pe pantă, în jos. Păcat. Cîndva a fost de 5 stele.
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