Август 2016 г.

Российская наука и мир (по материалам зарубежной электронной прессы)

CONTENTS / ОГЛАВЛЕНИЕ


• Russian scientists bracing for massive job losses
• Ministry denies plan to fire 10,000 scientists in cuts
• Alaska and Russia join forces to create 160-year database of walrus haulouts
• The town that reveals how Russia spills two Deepwater Horizons of oil each year
• Hot "new" material found to exist in nature
• Physicists have calculated a whole new way to generate super-strong magnetic fields
• Atomic Light
• Putin appoints church historian as science minister
• Russian scientists on the verge of solving the "muon puzzle"
• Peptide mutants may help to identify vulnerability in tumor cells

К 2019 году Минобрнауки предполагает сократить количество ученых более чем на 10 тыс. человек - в основном в институтах РАН.

MOSCOW - Russia's scientific community is reeling from news that the government plans to fire about 10,000 researchers over the next 3 years. Most layoffs would be from Russian Academy of Sciences (RAS) institutes, according to the online news site Gazeta.ru.
The staff cuts, representing about 17% of RAS's 49,000-strong workforce, are the latest move in a controversial and painful effort to overhaul the academy. The Federal Agency for Scientific Organizations (FASO), set up in 2013 to manage RAS's property and most of its budget, has recently stepped up efforts to make the academy leaner and meaner by merging institutes; several dozen mergers are planned.
Scientists decry the moves. In an open letter last month to President Vladimir Putin, more than 150 RAS researchers asserted that the reforms are eroding science's image in Russia; they warned of disastrous consequences for the nation, including a brain drain of young scientists and an "upsurge in activities of bureaucrats and impostors." The mergers are "a completely unnatural way of development," says Mikhail Sadovsky, a physicist at RAS's Institute of Electrophysics in Ekaterinburg. The 21 July letter, initiated by a group of discontented RAS researchers called the July 1 Club, argues that FASO must be brought to heel by placing it under RAS.
The specter of job losses has provoked even greater furor. Internal education and science ministry documents obtained by Gazeta.ru indicate that the layoffs are the price the scientific community must pay for a doubling of scientists' salaries earlier this year. Some prominent RAS institutes, including the Lebedev Physical Institute and the Prokhorov General Physics Institute, both in Moscow, have already begun dismissing staff, according to the RAS scientists' trade union. The documents acknowledge that layoffs will erode productivity.
The ministry told Gazeta.ru that it does not plan to fire scientists, although it does not dispute the documents' authenticity. A spokesman for the Kremlin says the government gives the scientists' concerns "great attention" but that it sees "positive results" from the ongoing reforms and will let them play out.

Минобрнауки официально опровергло сведения о предстоящем массовом увольнении ученых из-за отсутствия средств в бюджете, хотя, по некоторым источникам, от 5% до 10% российских ученых все же могут быть сокращены.

The Russian Ministry of Education and Science has officially denied reports in some Russian media outlets that the national government plans to fire about 10,000 scientists over the next three years, due to lack of funds in the Russian federal budget.
Gazeta.ru reported in early August that a 17% cut of the Russian Academy of Sciences' 49,000-strong workforce was planned.
The Russian Academy of Sciences or RAS has partially confirmed that some cuts may be undertaken this year and the Union of Education and Science Workers says the threat of massive cuts is real.
But Anna Usacheva, director of the department of information policy of the Russian Ministry of Education and Science, said: "The ministry has no plans to conduct massive cuts of scientists and researchers in Russia. On the contrary, since the beginning of the current year salaries for university professors and academicians have been doubled.
"In 2017 the level of these salaries will be retained. This has already been approved by the Russian Prime Minister Dmitry Medvedev during the last meeting in the Russian government."
Vladimir Fortov, president of the RAS, said: "To date, we have not received any instructions from the national government to start preparations for massive cuts of scientists of the national Academy of Sciences."
He said the RAS has its own mechanisms for making optimum cuts.
"Probably the most important thing is to avoid cuts of the really working, the most talented scientists. The budgets are very tight these times, while the Russian government has no plans to increase funding of domestic [national] science in the middle term."
Nevertheless, Fortov has partially confirmed that some cuts might be completed already by the end of the current year, while the RAS has already started the required consultations with the Federal Agency for Scientific Organisations regarding this issue.
According to some sources close to RAS, this year 5% to 10% of Russian scientists may be cut, which, however, will be significantly lower than the announced figures of 10,000 people (17%).
According to Tatiana Kupriyanova, deputy chair of the Union of Education and Science Workers in Russia, a threat of massive cuts of Russian scientists is real as the Russian Ministry of Finance has already informed the Russian government that further allocation of funds for the needs of national science from the national Reserve Fund and National Welfare Fund may pose a threat to the implementation of the Russian federal budget.
However, according to an analysis by the workers' union, the cuts could begin in October of the current year after the parliamentary elections in Russia, which are scheduled for 20 September. The Russian association of students said planned cuts will not have a catastrophic effect on national science, since in recent years the level of teaching at Russian universities and the level of research and development activities at the domestic scientific institutions has significantly declined, and up to 60% of the members of the RAS and university professors are not involved in any scientific activities.
This is also reflected by the content of the majority of Russian doctoral and masters dissertations, which is currently weak and usually has little to do with scientific discoveries and developments.

Российские и американские ученые создали совместную базу данных, каталогизировав сведения о расположении сезонных лежбищ моржей на берегах Чукотского и Берингова моря за период с 1852 по 2016 гг.

When Russian explorers sailed that nation's northeastern coastline along the Chukchi Sea in 1852, they were startled when they encountered about 150 belligerent walruses crowding a flat rock.
As they sailed toward the animals, they heard a "loud roar" that was "similar to an elephant's voice," said Carl von Ditmar, a Baltic-German scientist on the expedition. As the mariners approached the rock, "Walruses only raised their heads, terribly snorting and glaring at us with their big yellow eyes," he wrote in his book detailing travels and experiences in Kamchatka from 1851 to 1855.
Now that 19th-century account is part of a newly compiled United States-Russia database that tracks a century and a half of Pacific walrus haulouts onto shores of the Chukchi and Bering seas and the associated marine waters. The database, released by the U.S. Geological Survey, details records of onshore walrus gatherings of various sizes on both sides of the Bering Strait.
Walruses have long been pulling their large bodies out of the water to rest on shore, whether in groups of just a few or in big congregations of thousands, as the database shows. Big gatherings of males waiting for sea ice to recede typically congregate in places like western Alaska's Walrus Islands State Game Sanctuary.
But there is a new trend. Large concentrations of females and their young are hauling out in the northern areas of the species' habitat. The Chukchi Sea ice that those walruses previously used for resting platforms in between food-foraging dives has become increasingly scarce in summer and fall months.
"This trend of female haulouts up in the Chukchi Sea where they were previously hauling out on sea ice, that's the big difference," said Tony Fischbach, a co-author of the database and walrus expert at the U.S. Geological Survey.
Late-summer or early fall congregations of tens of thousands of adult females and calves have appeared nearly every year since 2007, a year of extreme ice melt, at a site near Point Lay on the Alaska side of the Chukchi. The behavior of animals when they are there is not always consistent, Fischbach said. Last year, for example, walruses that hauled up swam away quickly, possibly a sign that food in the area was more scarce than in other years, he said. "Last year they sort of hit the shore and headed straight to Russia," he said.
There are more big walrus congregations on the Russian side, though they have been less spotlighted than the Point Lay gathering. One such site is near the Chukotka village of Vankarem, where locals have set up patrols to keep the walruses undisturbed to prevent deadly stampedes. The patrols also aim to keep villagers safe from polar bears attracted to the walrus crowds.
At Chukotka's Cape Serdtse-Kamen, a site where walruses from Alaska and Russia converge in October and November before starting their southward migration, the animals used the land for haulouts only irregularly before 1990, and in crowds of no more than 12,000, according to Russian scientists. But now those haulouts are annual events, and the numbers are huge - nearly 100,000 amassed along a 12-mile coastline. It is likely that all the Chukchi walruses were ending up on the beach there at some point in the fall, according to the scientists.
Database co-author Anatoly Kochnev, a veteran biologist with the Russian Academy of Sciences, and his colleagues have been monitoring the site since 2009. The walruses have crowded around the cabin they use as a research station, and at times have pushed against the outer walls, Fischbach said.
The 1852 gathering recorded by von Ditmar was at a point near Cape Kronotsky on Russia's Kamchatka Peninsula. That area, near the southern part of the Pacific walruses' range, is now a nature reserve.
Von Ditmar's team watched the walruses as closely as possible, and he noted that the animals, seemingly ungainly on land, were graceful in the water. On the ground, the walrus body "by virtue of its own huge gravity completely flattened, like a bellows filled with viscous fluid," he wrote. But in the water, in "the native element, they with great ability and quickness began to swim, and somersault dive." The team shot some to dissect, triggering a stampede of survivors into the water, according to the account.
Modern methods of data collection are much more sophisticated than they were in von Ditmar's day. Scientists use digital photographs that allow them to count every image recorded. They track movements with devices that send signals to satellite. Fischbach and his colleagues have, most recently, combined radio telemetry with statistical modeling to predict activity patterns.
The scientists who compiled the database sought to use consistent methods, which evolved through technology, cross-border exchanges and legal protections like the Marine Mammal Protection Act enacted in 1972.
Combining modern observations with those made long ago was difficult, necessitating the use of broad estimates, he said.
"There's profound variability in how people assess the number of walruses on shore," he said. "In general, we take it all with a large grain of salt."

Разливы нефти в районе Усинского месторождения (Республика Коми) относительно невелики и редко привлекают внимание общественности, но их масштабы быстро растут и представляют угрозу для рыбных ресурсов, пастбищ и питьевой воды. Основная проблема в том, что 60% трубопровода сильно изношено.

The Komi Republic in northern Russia is renowned for its many lakes, but sites contaminated by oil are almost just as easy to find in the Usinsk oilfields. From pumps dripping oil and huge ponds of black sludge to dying trees and undergrowth - a likely sign of an underground pipeline leak - these spills are relatively small and rarely garner media attention.
But they add up quickly, threatening fish stocks, pasture land and drinking water. According to the natural resources and environment minister, Sergei Donskoi, 1.5m tonnes of oil are spilled in Russia each year. That's more than twice the amount released by the record-breaking Deepwater Horizon oil spill in the Gulf of Mexico in 2010.
The main problem, according to the natural resources ministry, is that 60% of pipeline infrastructure is deteriorated. And with fines inexpensive and oversight lax, oil companies find it more profitable to patch up holes and pour sand on spills - or do nothing at all - than invest in quality infrastructure and comprehensive cleanups, according to activists.
"The pipelines are very worn out, they're left over from the USSR," said Greenpeace research projects coordinator, Vasily Yablokov. "The oil companies have realised they're losing a lot of oil and are starting to replace them, but it's laughable. They need to do much more."
While Russia's oil and gas production provides more than half the state budget every year, it exacts a huge price on the environment and local residents. A state energy statistics bureau told Greenpeace it had registered 11,709 pipeline breaks in Russia in 2014. In contrast, Canada reported five pipeline accidents (involving human injury) and 133 incidents involving natural gas and oil pipelines in 2014.
The Komi Republic is where Russia's first oil production facility opened in 1745, and the Soviet Union started developing the country's modern oil industry here in the 1960s and 70s. Usinsk, a sleepy town of 39,000 people, is the regional oil hub. The Usinsk oil field is licensed largely to Lukoil, which bought its Komi oil drilling assets from Komitek in 1999 and began expanding production.
"More Usinsk oil to the motherland!" giant letters proclaim on top of one prefab flat block. Just south of the Arctic Circle, the sun doesn't even set in Usinsk in the summer, and it's reachable by car only when rivers freeze to make "winter roads".
Komi's aging oil infrastructure has been prone to accidents. In 1994, a pipeline break in Usinsk gushed up more than 60,000 tonnes of oil (many estimates put that figure at twice as much), one of the biggest spills ever on land. Spills in 2013, 2014 and 2015 released hundreds of tonnes of oil on to the snow and river ice.
Greenpeace says that in 2014, a 10-day "oil patrol" by its volunteers discovered 201 contaminated sites (mostly from pipeline breaks) in the Usinsk oilfield, which is licensed largely to Lukoil, and filed official complaints for each. A trip organised by Greenpeace and the local news site 7x7 in July reported that at least six of these sites were still filled with oil.
At a meeting with journalists and Greenpeace, Lukoil-Komi representatives said the 201 sites had been investigated and no oil spill was found at 67 of them.However, Greenpeace has photographs of violations at every site. Representatives admitted the subcontractor that checked the sites could have mistaken the coordinates of some of them. According to Lukoil spokesman Sergei Makarov, a new programme by the company has liquidated more than 50 pools of leaked oil.
But since satellite imagery has shown likely spills in areas of the Usinsk oilfields that Greenpeace cannot access, the actual number of contaminated sites is likely far higher than 201, Yablokov believes.
"It's like a train that they're laying rails under as it goes, it goes further and they lay more rail, and that train is oil extraction in the regions," Yablokov said.
Besides the six known sites, Greenpeace said the July visit also found three new oil spills along the way, including one near a site that Greenpeace volunteers removed 20 tonnes of oil from in 2014.
At the site of one pipeline break, the Guardian saw that a large amount of oil had been removed by Lukoil workers and the site considered "reclaimed". But the haphazard canals criss-crossing it were still full of thick, unctuous water with a rainbow film on top, and white paint on the birch tree trunks could not cover the black trace of oil, Greenpeace says.
Locals in the villages around Usinsk complain that the frequent oil spills pollute their drinking water, contaminate the river fish and reindeer they depend on for food and cause chronic health conditions.
Statistics obtained in 2010 by local activists from the hospital in Ust-Usa, a village of 1,300 on the Pechora river that has suffered from many of the large spills, showed rises in almost every kind of illness. Nervous system illnesses in adults, for instance, grew from 26 in 1995 to 70 in 2009. In patients under 18 years of age, they skyrocketed from 72 to 254.
Spokesman Sergei Makarov said Lukoil-Komi was investing 20bn roubles (£230m) in environmental measures and would change 370km of old pipeline in 2016, out of a 7,000km-long pipeline network in the region. The company reported only six oil spills in 2015, although Makarov admitted "some of our employees don't want to report (spills) because a leak means poor quality work".
In late May, more than 50 residents of Ust-Usa protested the effects of oil drilling and plans for a new oil well near the village. Lukoil Komi plans to increase its production from 15.8m tonnes of oil in 2014 to 21.5m tonnes in 2019.
"We're not telling oil companies to leave, we are saying drill in a way so that we can live with clean air and water," local biology teacher and activist Yekaterina Dyachkova said.
"Of course we depend on oil companies because there is no other work."
The aftermath of oil spills isn't limited to Komi. Northern rivers such as the Pechora carry 500,000 tonnes of oil into the Arctic Ocean every year, the state hydrometeorology and environmental monitoring service reported in 2011. More than 11,000 people have signed a Greenpeace petition demanding oil companies be required to replace by 2022 all oil pipelines more than 25 years old.
Without stricter enforcement, the situation is unlikely to change. The average return on assets for oil companies in Russia was twice as high as in other countries, according to a recent Greenpeace report. That's thanks to huge government tax breaks and subsidies, as well as "conditions in which oil companies are able to avoid full financial responsibility for oil spills" and not replace pipelines, it said.
"We need the cost of oil drilling to include protecting nature," Yablokov said. "It won't be quite as profitable a business, but we will be able to preserve the environment."

Канадские и российские минералоги обнаружили, что найденные в середине ХХ века на якутских угольных месторождениях минералы, названные степановит и жемчужниковит, являются первыми найденными в природе веществами с металл-органическими каркасными структурами (подкласс координационных полимеров). С 1990-х гг. такие полимеры создавались в лабораториях, поскольку считалось, что в естественной среде их не существует.

One of the hottest new materials is a class of porous solids known as metal-organic frameworks, or MOFs. These man-made materials were introduced in the 1990s, and researchers around the world are working on ways to use them as molecular sponges for applications such as hydrogen storage, carbon sequestration, or photovoltaics.
Now, a surprising discovery by scientists in Canada and Russia reveals that MOFs also exist in nature - albeit in the form of rare minerals found so far only in Siberian coal mines.
The finding, published in the journal Science Advances, "completely changes the normal view of these highly popular materials as solely artificial, 'designer' solids," says senior author Tomislav Friščić, an associate professor of chemistry at McGill University in Montreal. "This raises the possibility that there might be other, more abundant, MOF minerals out there."
The twisting path to the discovery began six years ago, when Friščić came across a mention of the minerals stepanovite and zhemchuzhnikovite in a Canadian mineralogy journal. The crystal structure of the minerals, found in Russia between the 1940s and 1960s, hadn't been fully determined. But the Russian mineralogists who discovered them had analyzed their chemical composition and the basic parameters of their structures, using a technique known as X-ray powder diffraction. To Friščić, those parameters hinted that the minerals could be structurally similar to a type of man-made MOF.
His curiosity piqued, Friščić began looking for samples of the rare minerals, reaching out to experts, museums and vendors in Russia and elsewhere. After a promising lead with a mining museum in Saint Petersburg failed to pan out, Igor Huskić, a graduate student in the Friščić research group at McGill turned his attention to synthesizing analogues of the minerals in the lab - and succeeded. But a major journal last year declined to publish the team's work, in part because the original description of the minerals had been reported in a somewhat obscure Russian mineralogical journal.
Then, the McGill chemists caught a break: with the help of a crystallographer colleague in Venezuela, they connected with two prominent Russian mineralogists: Sergey Krivovichev, a professor at Saint Petersburg State University, and Prof. Igor Pekov of Lomonosov Moscow State University.
Krivovichev and Pekov were able to obtain the original samples of the two rare minerals, which had been found decades earlier in a coal mine deep beneath the Siberian permafrost. The Russian experts were also able to determine the crystal structures of the minerals. These findings confirmed the McGill researchers' initial results from their lab synthesis.
Stepanovite and zhemchuzhnikovite have the elaborate, honeycomb-like structure of MOFs, characterized at the molecular level by large voids. The two minerals aren't, however, representative of the hottest varieties of MOFs - those that are being developed for use in hydrogen-fueled cars or to capture waste carbon dioxide.
As a result, Friščić and his collaborators are now broadening their research to determine if other, more abundant minerals have porous structures that could make them suitable for uses such as hydrogen storage or even drug delivery.
In any event, the discovery of MOF structures in the two rare minerals already is "paradigm-changing" Friščić says. If scientists had been able to determine those structures in the 1960s, he notes, the development of MOF materials "might have been accelerated by 30 years."

Физики из России (МИФИ, ИВТ СО РАН), Германии и Италии предложили новый способ генерации мощных магнитных полей с помощью лазеров, основанный на так называемом эффекте Фарадея. В природе подобные суперсильные поля существуют только в космосе. Пока способ представляет собой лишь теоретические расчеты - проверить его на практике невозможно за отсутствием лазеров необходимой мощности.

Researchers have proposed a new way to use lasers to generate magnetic fields that are at least one order of magnitude stronger than anything we can currently produce on Earth.
In nature, such super-strong fields only exist in space, and they could be the key to harnessing the clean power of nuclear fusion and modelling astrophysical processes in the lab.
It's exciting stuff, but so far, physicists have only used theoretical calculations to show that the technique could work, and it hasn't been experimentally verified as yet for a good reason - we currently don't have lasers strong enough to test it out.
But on paper, the premise works, thanks to something known as the Faraday effect, which is the result of a strange interaction between light and a magnetic field.
It's a little complicated, but basically the Faraday effect refers to the fact that if an electromagnetic wave, such as visible light, is travelling through a non-magnetic medium, then its polarisation plane will be rotating in the presence of a constant magnetic field.
To break that down a bit further, when light is polarised, it means all the light waves are vibrating in a single plane. But the angle of that plane can rotate.
And, because of the Faraday effect, as light passes through a medium, the polarisation plane will rotate according to a constant magnetic field.
What does any of that have to do with lasers? Well, the spin off of the Faraday effect is that, if you mess with the polarisation of the visible light travelling through a magnetic medium, it will generate a magnetic field.
The stronger the electromagnetic wave, the higher the magnetic field it can produce - so if you use really strong lasers, you should be able to produce a really badass field.
This is an idea physicists toyed around with back in the 1960s, but the reason it never went anywhere is because the Faraday effect also requires absorption to take place - something that usually happens through electrons colliding.
Once you get to a certain intensity of laser, the electrons become ultra-relativistic, which means they collide a whole lot less often, and conventional absorption eventually stops happening. Because of this, researchers have assumed that a laser powerful enough to generate a super-strong magnetic field would also stop the absorption process from happening, which would void the Faraday effect.
But now researchers from Russia, Italy, and Germany have hypothesised that, at very high laser wave intensities, the absorption can be effectively provided by radiation friction, instead of electron collisions.
And this specific type of friction, on paper at least, can lead to the generation of a super-strong magnetic field.
According to the team's calculations, a powerful enough laser would be able to produce magnetic fields with a strength of several giga-Gauss (Gauss is the unit used to measure magnetic fields).
To put that into perspective, a giga-Gauss is 10⁹ Gauss, or 1,000,000,000 Gauss. The crazy strong magnetic field produced by an MRI machine can only get up to 70,000 Gauss, whereas the surface of a neutron star is around 10¹² Gauss.
Magnetic fields that we can produce in the lab today max out at around 10⁸ Gauss - and they struggle to efficiently control nuclear fusion for long periods of time, which is where this new technique would come in handy.
It would also allow researchers to recreate the crazy strong magnetic conditions in space inside the lab.
"A new research field - laboratory astrophysics - has emerged relatively recently, and now it is very fast-developing," said one of the researchers, Sergey Popruzhenko from the Moscow Engineering Physics Institute in Russia. "Our work is of particular interest because it suggests new opportunities in this field."
The challenge will be to experimentally test this new technique, to see if it works in real life, just as it does on paper. But while Popruzhenko predicts we'll be able to do this in the "near future", we need to wait until we have a laser powerful enough.
The good news is that three of them are now under construction as part of the European project, Extreme Light Infrastructure, being built in the Czech Republic, Romania, and Hungary, so we're already making progress.
"These laser facilities will be capable of the intensities required for the generation of super-strong magnetic fields due to radiation friction and also for the observation of many other fundamental strong-field effects," said Popruzhenko.
The research has been published in the New Journal of Physics.

Cокращенная версия эссе «Атомный свет. Академгородок Пабло Ортиса Монастерио» из книги «Академгородок», выпущенной в издательстве RM/Conaculta. В издание вошли фотографии известного мексиканского фотографа, сделанные несколько лет назад в институтах Академгородка.

Дмитрия Ливанова на посту главы Минобрнауки сменила Ольга Васильева. Чего ожидать от нового министра?

Russian President Vladimir Putin has appointed a church historian as the country's new science and education minister.
On 19 August, the president announced that Olga Vasilyeva would succeed the current science minister, Dmitry Livanov, who will become presidential envoy on trade and economic relations with Ukraine, according to the Russian news agency Interfax.
During his 4-year term as minister, Livanov oversaw a radical overhaul of the Russian Academy of Sciences, Russia's main basic research organization. The formerly separate academies of sciences, medical sciences and agricultural science were merged and put under the governance of a federal agency. Livanov told Nature last year that the academy's future role will mainly be to provide expert advice to the government and society.
But many members of the academy, which runs hundreds of research institutes across Russia, are unhappy with the changes and with the way that Livanov handled the painful reform. Vladimir Ivanov, a vice-president of the academy, told the Rossiyskaya Gazeta news portal that he welcomed the move because Livanov had failed to involve scientists and academic officials in the overhaul of the academy.
Unexpected proposal
In making the decision, Putin followed a proposal made by prime minister Dmitry Medvedev, according to Interfax.
Putin gave no reason for Livanov's replacement. The minister was unpopular in public for his education policies - many parents are upset, for example, that they must now pay fees for their children's school textbooks, according to Rossiyskaya Gazeta. But whether a lack of public popularity was the reason for Livanov's dismissal is unclear. Putin and Medvedev did value Livanov's work, and they say that they consider his experience to be important in other spheres, according to the Russian news agency TASS.
Some scientists fear that Vasilyeva's appointment might mark a rise of Christian orthodoxy and religious attitudes in the realms of school education, higher learning and public life. But Vasilyeva, formerly in charge of religious public education in the presidential administration, told Interfax that religion will not interfere with her future work as education and science minister.

Есть вероятность, что в ближайшие годы будет решена так называемая «мюонная загадка». Состоит она в том, что количество долетающих до Земли в космических лучах элементарных частиц мюонов гораздо больше, чем должно быть согласно расчетам.
Значительный вклад в это исследование внесли ученые из Национального исследовательского ядерного университета (МИФИ), изучающие мюоны при помощи экспериментального комплекса, предназначенного для исследования всех компонентов космических лучей у поверхности Земли.

It may only take scientists a few more years to solve one of the biggest puzzles in modern elementary particle physics, the so-called "muon puzzle." Russian scientists from the National Research Nuclear University (MEPhI) will make a significant contribution to this research.
Cosmic ray particles in the Earth's atmosphere undergo a series of transformations and, as a result, produce elementary particles or muons. Muons reach the Earth's surface and can therefore be registered by ground-based detectors. Several years ago, scientists noticed that the number of registered muons is by tens of percentage points higher than it should be, according to existing theories. This phenomenon was called the muon puzzle.
The first clue to the muon puzzle was found in 2002-2007 during a long series of experiments on the DECOR facility in MEPhI. Later, the excess of muons was confirmed by experiments at the Pierre Auger Observatory in Argentina.
NEVOD Scientific and Educational Center, which is a subdivision of the Institute of Nuclear Physics and Engineering of MEPhI, is studying muons with the world's only multi-purpose neutrino water detector, which is used to research all cosmic ray components near the Earth's surface. MEPhI researchers spoke about the latest results of the cosmic ray experiments with NEVOD at the National Cosmic Ray Conference in Dubna, Moscow Region.
"In the past several years, we have increased the amount of experimental data three- or four-fold and, as a result, improved the precision of measurements. One of the tasks in the muon puzzle experimental research is to count not only the number of muons but to measure their energy characteristics. We started the experiment of measuring the energies of muons back in 2012, and it is still in progress. First, we used the coordinate-tracking detector DECOR to register a group of muons. Then we measured what energy they deposited in the NEVOD Cherenkov water detector," said Rostislav Kokoulin, NEVOD Senior Research Associate.
The scientists intend to find out whether the mean energy of muons has changed, in addition to their excess number.
"When the experiment proves the excess of energy exists, it will become clear what changes in the theoretical model are required. Now MEPhI is building new facilities that will operate alongside DECOR and NEVOD. This will allow the scientists to expand the set of characteristics under observation and make the measurements more precise."
Kokoulin added that the solution to the "muon puzzle" is a question of three to five years..
"Once the muon puzzle is solved, we will have a more accurate idea of the nuclear cascade process initiated by interactions of ultra-high energy particles. This understanding is required for studying characteristics of the universe and the processes within it," the scientist stressed.

Исследователи из МФТИ, Института биомедицинской химии РАН, Института энергетических проблем химической физики РАН и ФНКЦ физико-химической медицины разработали алгоритм для обнаружения в клетках мутантных белков с помощью масс-спектрометрического анализа и выделения мутаций, связанные с возможным развитием рака.

Researchers from MIPT, the Institute of Biomedical Chemistry, the Institute for Energy Problems of Chemical Physics, and the Research Institute of Physico-Chemical Medicine have presented an algorithm to detect mutant proteins based on mass spectrometry data and the results of exome sequencing. Using this new approach, the scientists have discovered unique genome variants, some of which are linked to cancer development. Studying mutant peptides will help to detect weaknesses in tumor cells in search for more effective drug treatments. The results have been published in the journal Proteomics.
Proteomics and Big Data
It seems as if the term "big data" is relatively new. However, it is impossible to imagine any science that would not use large amounts of data. In biology, big data enables scientists to, on the one hand, conduct large-scale experiments and extract more useful data from biological material. On the other hand, it is becoming increasingly difficult to reveal important patterns of high specificity within the large amount of information. To cope with this problem, scientists are increasingly focusing on developing complex algorithms and/or the workflows for filtering and analyzing the data.
Proteomics - the large-scale study of proteins of cells and entire organisms - is no exception. Generally, proteins, peptides, and their fragments can be analyzed using mass spectrometry. Mass spectrometry provides peptide fragmentation information specific to the amino acid sequence and, thus, allows scientists to identify proteins present in the original sample. A number of algorithms called a search engine are currently available for protein identification. These algorithms take the peptide fragmentation patterns provided by mass spectrometry, match them with a protein database and return the list of proteins corresponding to the experimental data.
However, this approach is not entirely suitable for proteins that are not encoded in a reference genome. If a mutant protein from a cancer cell does not present in the search database, then the so-called variant peptide corresponding to the mutated part of the protein would not be identified. This is where proteogenomics comes in - a rapidly growing area of biological research at the intersection of genomics and proteomics. Variant peptides identified using the proteogenomic approach provide invaluable information for gene annotation - information which is difficult or impossible to ascertain using standard annotation methods.
Expansion of the protein database
In their paper, the Russian scientists describe a workflow for searching variant peptides from mutant proteins enabling them to compare the mass spectrometry results of different groups and laboratories for unambiguous marking of cancer mutations. The effectiveness of their approach has been tested using HEK-293 cells. HEK-293 (Human Embryonic Kidney 293) cells are a specific cell line originally derived from human embryonic kidney cells grown in a tissue culture. HEK-293 cells have been widely used in cell biology research for many years because of their reliable growth and propensity for transfection.
In addition to their own experimental data, the researchers used the mass spectrometry results from two recent studies analysing HEK-293 cell proteomes. They generated the so-called customized database for proteogenomic analysis based on exome sequencing of HEK-293 cells. An exome is formed by exons (part of a gene that codes an amino acid sequence). As a result, the customized protein database now has 1336 sequences of mutant proteins in addition to the reference database of human proteins. This simply means that the protein "dictionary" has grown. Without this improvement it would be impossible to find the "wrong" mutant proteins. A cancer cell mutates more often than a regular cell, which is why known differences between proteins in cancer and "reference" cells will help scientists to find out more about tumor cells.
With the mass spectrometry data available from two previous studies and the own experimental results, the Russian scientists identified peptides and the corresponding proteins contained in the cell. Using the proteogenomic analysis with an expanded peptide database, the authors discovered 113 unique variant peptide sequences in HEK-293 cells referring to the exons of 103 genes.
Some of the mutations discovered had previously been proven to be connected with different types of cancer. These mutant proteins could possibly facilitate the survival and multiplication of the cells. In particular, one of the variants identified is related to the p53 protein which is known to suppress the malignant transformations.
"Our approach may be used to search for cancer-associated mutations based on proteomic analysis. This will help in studying the protein expressions in tumors and provide further basis for developing drugs targeting the mutant proteins produced in tumor cells," says Dr. Michael Gorshkov, one of the collaborators in the project, the Head of the Laboratory of Physical and Chemical Methods for Structure Analysis at the Institute for Energy Problems of Chemical Physics, and a member of MIPT's Department of Chemical Physics.

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