Декабрь 2015 г. |
Российская наука и мир (по материалам зарубежной электронной прессы) |
New Electronics / 03 December 2015
Low current spintronics could be adopted in all future electronics
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Физики из МФТИ и Российского квантового центра продемонстрировали метод создания магнитных вихрей в спинтронных устройствах при небольших затратах энергии. Оказалось, что в системах ферромагнетик-топологический изолятор этот процесс является резонансным, и для максимальной эффективности нужно просто подобрать определенную частоту и плотность переменного тока.
Статья "Large amplitude vortex gyration in permalloy/Bi2Se3-like heterostructures" опубликована в журнале Physical Review B.
A team of scientists, from the Moscow Institute of Physics and Technology (MIPT) and the Russian Quantum Centre, claim to have demonstrated a method of exciting magnetic vortices using less current.
Controlling magnetic vortices, through spin or otherwise, is what scientists are researching as a foundation for the electronics of the future, called spintronics. In spintronics, information can be transmitted by spin rather than electronic charge, the charged particles do not necessarily need to move anywhere as information will be transmitting "along the chain" via the spin.
Using spin to transmit a unit of information requires less time and energy than a similar operation in modern electronics.
The scientists examined the process of an alternating radio frequency current, of approximately 1GHz, passing along the surface between a ferromagnet and topological insulator.
The study found that in order to excite magnetic vortices with a topological insulator, AC must be used, as DC has almost no effect on them. When AC was applied, a sharp resonance excitation of the vortices was observed. The scientists also noted that the current densities required to excite the vortices were several times lower than previously observed.
Previous experimental studies have shown that current passing along the surface between different layers of a heterostructure such as this is able to generate a torque. The authors of the paper have demonstrated that it is possible to effectively excite magnetic vortices using this torque.
Research into spintronics is essential for the development of modern technologies as Moore's Law is pushing the technology to its limits. The Russian scientists say it is possible that in the future all technologies will switch from using electrical charges to particle spins, which require minimal amounts of energy and will increase speed thousands of times.
© Copyright Findlay Media Ltd (a Mark Allen Group company) 2015.
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Times Higher Education (THE) / December 3, 2015
Russia internationalisation "compromised" by political conflicts "Confrontational policies" will have long-term consequences on universities' international collaborations, claims academic.
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Журнал Times Higher Education опубликовал очередной рейтинг университетов стран с развивающейся экономикой и стран БРИКС. 11 российских вузов вошли в первую сотню, еще четыре - во вторую. НГУ по-прежнему на 34-м месте, МГУ поднялся с 5-го на 3-е. Отмечено также, что хотя запущенный три года назад проект 5-100 (повышение конкурентоспособности ведущих российских университетов среди мировых научно-образовательных центров) уже дал некоторые результаты, в будущем у российских вузов могут возникнуть проблемы с международным сотрудничеством.
The scope for Russian universities to collaborate with international partners has been "compromised" by the country's "confrontational policies on the global political arena", a higher education scholar has claimed.
Anatoly Oleksiyenko, associate professor in the division of policy, administration and social sciences education at the University of Hong Kong, said Russian institutions had "huge potential before 2014". He added that the Russian government's Project 5-100 - launched in 2012 and designed to provide enough federal support to help at least five institutions enter the world top 100 by 2020 - was "very motivational". But he said that "internationalisation was compromised following the 2014 crisis in Ukraine, when Russian politicians pulled their country into a major conflict with the West".
"Over the past two years, the Russian political establishment has only intensified its confrontational policies in the global political arena. These will have long-term effects on the universities' international collaborations," he told Times Higher Education.
Speaking about the THE BRICS & Emerging Economies Rankings 2016, in which Russia is a stand-out performer, Dr Oleksiyenko said he has seen improvements in Russia's science and technology research, but it is "difficult to predict" how social scientists in the country "will fare in this complicated environment".
"Russian social science has a tradition of dissident scholarship, which means that most of the influential publications would appear in foreign universities, given that critically minded philosophers, sociologists, political scientists and others tend to leave when repressive and confrontational governance takes hold at home."
He suggested that China's success in the rankings is in part due to academic collaborations.
"Many Chinese academics, who hold Ivy League doctoral degrees, were very smart in managing their collaborations with their former academic supervisors, and that has been their competitive advantage in comparison with their counterparts in other BRICS countries," he said.
"Besides, the Chinese government made significant efforts to reintegrate overseas scientific talent, and thus enhanced local academic capacity to perform in accordance with global meritocratic measurements."
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EurekAlert! / 9-Dec-2015
Bacteriorhodopsin crystals consume their smaller counterparts The scientists have demonstrated that the larger crystals of the protein grow by "consuming" smaller crystals around them and creating "depletion zone" around themselves.
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Биофизики из МФТИ, наблюдая за кристаллами бактериородопсина (семейство мембранных светочувствительных белков), обнаружили, что крупные кристаллы растут за счет более мелких - попросту "поедают" их, оставляя вокруг себя опустошенные участки. Сама же кристаллизация происходит определенным образом, напоминая своим строением пчелиные соты.
Статья "Nucleation and Growth of Membrane Protein Crystals In Meso - A Fluorescence Microscopy Study" опубликована в журнале Crystal Growth & Design.
A group of biophysicists from Moscow Institute of Physics and Technology (MIPT) and their international colleagues have studied the crystallization of molecules of the membrane protein bacteriorhodopsin. The scientists have demonstrated that the larger crystals of the protein grow by "consuming" smaller crystals around them and creating "depletion zone" around themselves. The paper has been published in the scientific journal Crystal Growth & Design.
What are membrane proteins?
Membrane proteins are an important group of proteins that are present in any living organism. They are found on the surface of cell membranes (or even penetrate through them), and perform a number of different functions, mainly associated with receiving signals or transporting substances (the membrane itself is impermeable to many molecules).
For example, membrane proteins participate in signal transduction through nerve cells by restoring their condition after a nerve impulse has passed through, or reacting to adrenaline, causing the cells of our bodies to work harder under stress.
Why do we need their crystals?
In order to gain a better understanding of how proteins function, it is very important to know their molecular structure. It determines the way in which a protein interacts with other molecules (e.g. adrenaline). If we know the structure of a protein, computer methods can be used to accurately select molecules that will interact with the protein. This will make it cheaper and faster to develop drugs - more than 60% of drugs use membrane proteins as a target.
In order to determine the structure of a protein, the scientists first grow crystals of its molecules, then examine them under X-ray radiation and use the diffraction pattern to restore the structure of the protein - when arranged in a regular crystal lattice, all the atoms in a molecule greatly increase the radiation in particular directions, which enables scientists to precisely determine the location of the atoms.
How are the crystals obtained?
Two conditions are required to obtain protein crystals. Firstly, it must be "more favourable" for the protein molecules to be in a crystal, rather than a solution. This is relatively simple to achieve - all that needs to be done is to select the right components of the solution and their concentrations. Secondly, the protein molecules have to be allowed to move freely in the solution, so that new molecules are able to bind to the growing crystal.
If the protein is soluble, it is relatively simple to fulfil both of these conditions. However, if the protein is not soluble in water (this applies to all membrane proteins - their native environment is not a liquid, but a lipid membrane), then this can cause problems.
Even if it is possible to remove the protein from its membrane and allow it move around freely in the solution, it will simply lose its shape when it comes into contact with the different environment (it is said that the protein becomes denatured). When this happens, it will of course no longer be possible to obtain any information about its "native" structure. In order to allow a protein molecule to move freely in a solution without losing its structure, scientists use a special environment - a lipidic cubic phase.
The lipidic cubic phase (LCP) is a special three-dimensional structure formed by certain lipids (molecules that make up lipid membranes) at certain temperatures and in certain concentrations. In a solution, the cubic phase forms a complex two-dimensional surface along which membrane proteins are able to reach the growing crystal without leaving the comfort of their membrane.
It is similar to the way in which people walk in a park - despite the fact that paths (one-dimensional) are not all over the park, they can be used to get to almost any point in the two-dimensional park. It is the same in this case; the only difference is that the surface of the cubic phase, which represents the "paths" for the membrane proteins, is two-dimensional, and the "park" is three-dimensional (the entire space).
Using this structure, proteins are able to "travel" through a solution and provide new molecules for a growing crystal without leaving the comfort of their environment - the lipid membrane.
It should be noted that the use of such a complex technique to obtain crystals has already demonstrated positive results. Out of all of the structures of membrane proteins that are currently known, crystals for obtaining 40% of them were made by crystallization in the lipidic cubic phase (or, as scientists call it, in meso crystallization).
What did the authors of the paper do?
In their paper, the authors studied the growth of crystals of bacteriorhodopsin (which was used as a model protein of any membrane protein) using fluorescence microscopy. Over the course of a month, the scientists observed the growth of the crystals and examined how the distribution of bacteriorhodopsin in the sample changed over time. It turned out that at the beginning the crystals formed throughout the sample fairly evenly, however, after about a week clear depletion zones began to form around the faster growing crystals. In these zones there were only few small crystals, and the larger crystals were found only beyond these zones. It was found that the larger growing crystals not only take material from the solution in order to grow, but they "consume" their smaller counterparts that are close by.
In addition, the scientists discovered that crystallization does not start at random points in the sample, but along the boundaries of areas in the shape of a honeycomb.
"This pattern may have something to do with the fact that the cubic phase is not uniform throughout the sample, but forms small domains with boundaries where the likelihood of crystallization is greatest. It would appear that we have been able to observe these domains that, for an unknown reason, form "honeycomb" shapes. However, what is interesting is that if we learn how to control the size of these domains, we will be able to grow larger crystals, and consequently develop better and more accurate protein structures," commented Dr. Valentin Borshchevskiy, the main author of the paper and head of the Super-resolution microscopy group at the Research center of molecular mechanisms of aging and age-related diseases of MIPT.
According to data from the California Biomedical Research Organisation, the development of a completely new drug takes, on average, 12 years and will cost a company about 2.6 billion dollars. An understanding of how drug targets are structured (in 40% of cases they are GPCR membrane proteins) will, in the future, make it cheaper and faster to find drug molecules that act on them. It will also make it possible to develop drugs that act strictly on one type of receptor, which will reduce a drug's side effects.
Copyright © 2015 by the American Association for the Advancement of Science (AAAS).
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The Washington Post / December 10, 2015
Political scrutiny of education is "reasonable," Russia's education chief says
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Интервью министра образования Дмитрия Ливанова газете Washington Post. Как вернуть эмигрировавших ученых, зачем политика вмешивается в образование и какие ценности надо преподавать школьникам.
Russian Education Minister Dmitry Livanov sat down last month with The Washington Post for an interview about the intersection between education and politics in Russia. Livanov spoke shortly before visiting the United States, where he met with the Russian-language Academic Science Association and lectured at the Kennan Institute in Washington, D.C. The following is a condensed version of the interview.
You've discussed the importance of enticing Russian scholars to return to Russia. What can you offer them?
"Our approach is that science is international and scholars on the international level are in demand everywhere and they can work in any country.
"In the 1990s, Russia was probably the largest world donor of intellectuals and tens of thousands of our scientists left in search of better conditions for work. Others stayed in Russia but started to work in other fields besides science. It was a huge loss for Russian science, and now we are implementing several programs, including "mega-grants" to set up state-of-the-art laboratories at universities, aimed at bringing Russia back to the list of the world's scientific leaders. And of course we look at Russia's scientific diaspora, at scientists who left Russia, as a very powerful resource."
President Vladimir Putin this year spoke about foreign grants and funds attempting to steal talented young Russian students. Did you agree with those statements?
"There is nothing wrong with searching for bright and talented young people all over the world, and any country that wants to have first-class scientists would do that.
"For us, the most important thing is that this has nothing to do with political activity or the financing of political activity. I think that any international program implemented in our country by foreign funds in the natural sciences or humanities or public science will never cause any negative reaction as long as they are scientific programs and not linked to the financing of political activity or to drawing young people into political activity. We are not going to put up with this, and that was the argument of the president."
But in social science it is very difficult to distinguish between science and politics. Let's take the Dynasty Foundation, which was recognized as a foreign agent for promoting the nongovernmental organization Liberal Mission.
"I think it is always possible to tell one from another. The Dynasty Foundation fulfilled a very important mission by financing scientific research in different areas: natural sciences, mathematics, physics, etcetera, and it did very important work in popularizing scientific knowledge. But it also financed various NGOs involved in political activity in the Russian Federation. And this became a subject of investigation by the Ministry of Justice.
"What the foundation did in science was never restricted in any way. On the contrary, I valued the foundation's activity, and in February I personally handed [founder] Dmitry Zimin an award "For Loyalty to Science" from the Ministry of Education."
How has the growing tension between Russia and the United States affected cooperation in the sphere of education?
"I can say that cooperation in the sphere of education has not suffered - it has basically stayed at the same level. There are inter-universities contacts, and we can see that our universities and American universities are interested in working together as it was last year and as 10 years ago.
"As for scientific cooperation there are certain limitations in sectors like nuclear technologies and cooperation in energy."
Based on conversations I've had, there is some concern among U.S. academics doing political research in Russia that they could be detained or fined for their work, maybe evicted from the country. What has the ministry's role been in those cases?
"I don't know of many cases when an academic was fired because of certain political or ideological disagreements with the university staff with just one exception: the case in Nizhny Novgorod when the vice-rector for innovations [Kendrick White] was fired after a well-known commentator on a television show made some unpleasant remarks about him.
"I then officially expressed my point of view. I believe that every university in Russia or elsewhere should be absolutely free in its personnel policy; they can hire or fire staff as they wish. But making such decisions based just on a comment in a TV show is not smart." [White has since been reinstated as an aide to the university's rector.]
There is a sense more and more that politics is playing a role in education in Russia and that there are political forces that want that to happen.
"I think that politicians are closely watching what is happening in education, and this is reasonable since we are living through a period of turbulence in the international situation. It is not related so much to Ukraine or bilateral relations but more to the global challenges that all countries are facing. And this of course causes certain polarization in the society, not only in Russia but also in America and elsewhere. That is why politicians express their interest in education, in what is going on in Russian schools, in what teachers are telling students, in what is written in textbooks."
You don't see a conflict with the politicians?
"No, it is not the question of resistance. Our approach is that the system of education is part of our society and it is very important to have a dialogue between various parts of the society, including political parties, professionals in education and so on, so that people can talk, express their opinions. So our position here is not of resistance or some kind of defense."
You've supported a new public initiative for Russian schoolchildren to promote Russian national values. What values in particular does Russia want to teach schoolchildren, and are they different from Western values in some major way?
"We believe that any society creates a system for raising children that cannot be formally incorporated into education at schools or universities. There should be very active public organizations which will focus on socializing young people. This existed in the Soviet Union when we had the Pioneers and the Komsomol youth groups. These organizations exist in every country.
"We lost this informal system in the 1990s. The Pioneer organization and Komsomol ceased to exist, and there was a lot that was good about them. Of course there were bad things about excessive "politicization" and "ideologization", but there were good things like social projects and developing leadership skills. By the way, many of our leaders today used to hold high-ranking positions in Komsomol. So, it was a system of developing soft skills. Because schools should educate children and public organizations can work on developing leadership skills. That is why I think that a movement of schoolchildren will be a step in this very important direction."
Do you see this as an attempt to resurrect those organizations, the Pioneers and the Komsomol?
"I think the only similarity we can speak of now is in the scope of this movement, which will be active in every region, in every town, in every Russian school."
© 1996-2015 The Washington Post.
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PR Urgent / 2015-12-15
The First Russian Meteorite Expedition organized by Ural Federal University begins
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Уральский федеральный университет организовал первую российскую экспедицию по поиску метеоритов в Антарктиде. Поскольку в условиях Южного полюса метеориты сохраняются лучше, чем в любом другом месте Земли, исследователи надеются привезти интересные образцы, а также голубой лед с космической пылью (голубой лед - ледники, вздыбленные над породой из-за движения льда по склонам гор, происходившего в течение миллионов лет).
On December 14, the First Russian Meteorite Expedition to Antarctic started with a farewell ceremony held at Ural Federal University.
The team of six scientists taking part in the expedition came to the University in order to participate in the farewell ceremony after which they headed to the airport. They had to take several flights via Moscow and Dubai to Cape Town, before they reach Queen Maud Land in Antarctica. The team are hoping to find at least 100 meteorites during their two-week search. They will collect meteoritic matter and then, after January 10, will bring it to the Research and Educational Center "Nanomaterials and Nanotechnologies" at Ural Federal University. The scientific supervisor of the project is UrFU Professor Victor Grokhovsky.
According to prof. Grokhovsky, the blue ice of Antarctica contains meteorites and dust from the Moon and Mars: "Antarctica is a storehouse of space material and a variety of ores in general. There are "blue ice" territories, which in fact are glaciers rearing over rocks because of the movement of ice on the mountain slopes; they have been moving very slowly for millions of years. Powerful winds from the coast blow away the snow, sublimating ice. And in the ice there are a lot of meteorite fragments, which had been reaching the surface of our planet over the millions of years; you can just go and collect them. Meteorite is literally "free" material, which is as old as our planet - about 4.5 billion years old. Imagine how much you can learn about the origin of the universe, life, its natural laws and, therefore, the future of our planet!"
The scientists have promised to share the obtained results with their foreign colleagues.
The students, the management and partners of the university, and, of course, relatives and friends of the members of the expedition came to UrFU to wish good luck in a two-week journey of scientific discovery.
Having reached Cape Town, the group will perform a communication test with the Media Center of Ural Federal University, which will receive and spread information during the expedition. By December 19, the expedition plans to get to "Novolazarevskaya" station, situated at the coast of Queen Maud Land.
Reference
UrFU Antarctic Meteorite Expedition is the first scientific project in the history of modern Russia aimed at search of meteoritic matter on the southernmost continent. It became possible thanks to the University's participation in the "Project 5-100". The author of the research project is Professor Victor Grokhovsky, Ural Federal University.
The budget of the expedition is estimated at about 12.8 million rubles, most of the sum provided by Ural Federal University. Thanks to the efforts of the Students' Union of UrFU, 500 thousand rubles have been collected by means of crowdfunding, and some money was invested by sponsors, such as Ekaterinburg Engineering Company "Plana", who invested 1 million rubles. The clothes for the expedition members were sewed by the local company "Discovery", and the food supply was provided by "NL International".
The expedition will return to Ekaterinburg in January 2016. More trips are planned, after the collected material has been studied. Therefore, the fundraising for Russian expeditions to the Antarctic continues. Everyone can support the unique research project of the Russian scientists at the expedition's website: http://grokhovsky.urfu.ru/.
© 2014 - PR Urgent News. All Rights Reserved.
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Le Temps / Mercredi 16 décembre 2015
Le futur cosmodrome russe attendra L'année spatiale se termine en demi-teinte avec un tir de satellite raté et de gros doutes sur les orientations futures.
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Итоги деятельности российской космической отрасли в этом году. Первый пуск ракеты-носителя с нового космодрома "Восточный", запланированный на 25 декабря этого года, перенесен на апрель 2016, да и само расположение космодрома - вдали от промышленных и научных центров - по-прежнему остается спорным.
Hier, le 15 décembre, le lanceur russe Soyouz a acheminé avec succès trois spationautes à bord de la Station spatiale internationale. Cette réussite ne saurait cependant occulter que la fin de l'année 2015 est entachée par plusieurs mauvaises nouvelles pour le secteur spatial russe. Un satellite d'observation à double usage de nouvelle génération (Kanopouss-ST), dont l'élaboration a pris 15 ans, s'est désintégré dans l'atmosphère le 8 décembre après avoir échoué à se détacher de l'adaptateur le fixant au lanceur Soyouz 2-1. Kanopouss-ST devait, entre autre, permettre aux militaires russes de repérer les sous-marins ennemis.
Le budget spatial russe a été sévèrement revu à la baisse à cause de contraintes budgétaires liées à la crise économique. L'agence spatiale Roscosmos a indiqué lundi dernier que son budget pour les dix prochaines années sera de 1500 milliards de roubles (21,3 milliards de francs), soit moins de la moitié de ce que le Kremlin avait promis en début d'année (3400 milliards de roubles). C'est la troisième correction à la baisse en 2015.
Mais surtout, Moscou a échoué dans la course à la montre que se sont imposé les autorités russes pour la construction du nouveau cosmodrome de Vostochny ("oriental" en russe, parce qu'il est situé en extrême-orient, non loin de la frontière chinoise). Le tir inaugural n'aura pas lieu comme prévu pour le Noël catholique du 25 décembre, mais le 12 avril 2016, si tout se passe bien.
Pour les experts, les délais imposés n'ont pas de sens et s'expliquent par une obsession très russe pour les dates symboliques et la peur du chef. "Si le premier tir prévu devait être en 2015, c'est parce que cela figurait dans l'oukase du président Poutine signé en 2007. L'ordre du président doit absolument être exécuté, même s'il date de huit ans", ironise Andreï Ionine, membre de l'Académie spatiale russe. "Dorénavant, la date fixée est le 12 avril, parce que c'est une date symbolique [la fête de l'espace, ndr]. Je ne suis pas partisan de ces traditions soviétiques".
L'expert spatial indépendant Anatoly Zak estime qu'un délai est parfaitement normal et ne remet pas en cause Vostochny comme "un succès remarquable pour la Russie et ses ingénieurs". Il raille "Le gouvernement et ses médias affiliés s'offusquent des menaces sur les délais fixés par le président, comme si quelque chose d'irréversible allait se produire parce que le calendrier irréaliste n'est pas respecté".
De fait, Vostochny s'est embourbé dans une succession de scandales autour de détournements de fonds publics. 220 personnes sont visées par une vingtaine d'affaires criminelles. Cet été, devant le retard que prenait la construction, les autorités ont même fait appel à une "brigade" de 1200 étudiants (sous payés) pour effectuer le gros-oeuvre, ressuscitant une pratique soviétique détestée par la jeunesse. Peu avant, d'importants retards de salaires avaient poussé 720 ouvriers à un mouvement social émaillé de grèves de la faim.
Le feuilleton s'est emballé ces deux dernières semaines, au cours desquelles trois dirigeants d'entreprises travaillant sur le chantier ont été accusés de malversations pour une somme dépassant les 10 millions de francs. Une goutte d'eau à l'échelle du coût total de Vostochny, estimé à 180 milliards de roubles (2,6 milliards de francs) par le patron de Roscosmos Igor Komarov. D'autres estimations atteignent les 400 milliards de roubles (5,6 milliards de francs).
Vostochny sera le troisième cosmodrome de l'industrie spatiale russe, qui utilise pour l'instant Baïkonour (au Kazakhstan) et Plesetsk (grand nord de la Russie, réservé aux appareils militaires). Vostochny comptera à terme 10 pas de tirs pour des vols habités et automatisés. Il deviendra le principal cosmodrome pour les lanceurs de nouvelle génération (famille Angara) qui remplaceront les lanceurs lourds Proton.
Deux pas de tirs sont prévus pour les lanceurs Soyouz-2. "Vostochny est construit pour réduire la dépendance de la Russie envers Baïkonour, dont la location revient très cher [115 millions de dollars par an, ndr] sans compter les amendes en cas d'échecs", souligne Ivan Moïseev, directeur de l'Institut de politique spatiale. "Le coût de construction est raisonnable par rapport au budget du pays, et il est étalé dans le temps". Moïseev ajoute que "le premier tir depuis Vostochny sera l'événement spatial à suivre en 2016".
Situé à des milliers de kilomètres des centres industriels et scientifiques du secteur spatial russe, Vostochny reste controversé à cause des coûts logistiques et techniques qu'il entraîne. Sa localisation six degrés au nord de Baïkonour force à réduire la masse placée en orbite. Il pose également des risques écologiques: en cas de lancement raté, de graves incendies forestiers pourraient être déclenchés, dans une région qui en a déjà beaucoup souffert.
À l'origine partisan de Vostochny, Andreï Ionine se dit très déçu de voir l'Etat réduire la voilure car "l'objectif de départ était de faire du cosmodrome la base du développement de l'extrême-orient russe. Pas seulement des pas de tir, mais un centre scientifique attirant les industries de pointe et les jeunes diplômés. La Russie doit se tourner vers l'est, vers le marché de la zone Pacifique. Or, personne ne crée de base technologique autour du cosmodrome, qui va au final copier Kourou: un îlot au milieu de la jungle". De 2016, Ionine n'attend pas tant les premiers tirs depuis Vostochny qu'une "véritable stratégie spatiale russe. L'Etat doit définir des orientations claires, c'est là que se situe le problème".
© 2015 Le Temps SA.
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Medical Xpress / December 17, 2015
Researchers describe changes in intestinal microflora that are characteristic in diabetes
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Группа российских ученых (НИИ Физико-химической медицины, Государственный научно-исследовательский центр профилактической медицины, МФТИ) обнаружила, что присутствие в кишечнике человека бактерий родов Blautia, Serratia и Akkermansia может быть связано с развитием диабета 2-го типа. Бактерии могут быть и у здоровых людей, но при предиабете и диабете их количество значительно увеличивается.
Статья "Gut microbiota and diet in patients with different glucose tolerance" опубликована в журнале Endocrine Connections.
A group of Russian scientists, including Dr Elena Kostryukova and Maria Vakhitova has discovered that the presence of certain bacteria in the gut may be linked to the development of type 2 diabetes.
Type 2 diabetes, also known as non-insulin-dependent diabetes, is a serious metabolic disorder. The disease causes the body's cells to lose their ability to respond to insulin - the hormone that controls glucose uptake. As the cells are unable to interact with insulin, they stop absorbing glucose and are therefore starved of energy, even with adequate nutrition, a high level of glucose in the blood, and a sufficient amount of insulin (in type 1 diabetes the pancreas does not produce any insulin, which causes glucose deficiency in the body's cells).
According to the World Health Organization, there are approximately 285 million people with type 2 diabetes worldwide. The prevalence of the disease and the severity of its complications (people with diabetes are 20 times more at risk of developing gangrene of the lower limbs, for example) mean that doctors and scientists are not only looking for causes of the disorder, but also new methods of combating the disease. Recently, researchers have been developing serious arguments to support the theory that diabetes may be linked, among other things, to the composition of the microbial community living inside our intestines, the intestinal microbiota. Specialists from four Russian research centres studied changes in the microbiota of the large intestine, and their paper was recently published in the journal Endocrinology Connections.
The scientists analysed the gut microbiota composition in 92 patients, including 20 patients with type 2 diabetes and 48 healthy people without any chronic diseases; a further 24 people showed signs of a metabolic disorder which doctors had diagnosed as prediabetes - a condition that can lead to the development of type 2 diabetes over time. The glucose level, which is the most important metabolic indicator, was also monitored in the study participants by taking blood samples.
Gut microbiota is the name given to the entire population of microorganisms living in the intestines (even including certain single-celled fungi and archaea). They are also commonly called microflora - this is a historical term that emerged at a time when bacteria were considered a part of the plant kingdom.
Bacteria were the "focal point" of the study. In order to determine exactly which bacteria they were dealing with, the researchers analysed DNA extracted from stool samples. Having isolated the DNA, the scientists sequenced (counted and deciphered the sequence of base pairs in the DNA) the gene that encodes ribosomal RNA, rRNA - an important component of ribosomes, which are microscopic structures responsible for protein synthesis. The gene that encodes this structure is found in all classes of bacteria and there is a database that can be used to identify bacteria based on the nucleotide sequence in the gene. This part of bacterial DNA could be described as a bacterial passport.
After comparing the composition of the microbiome with the diagnosis (diabetes/prediabetes/normal glucose tolerance) and the diet of the study participants, the scientists came to a number of conclusions.
Most importantly, the researchers were able to link the level of glucose intolerance with the presence of three specific types of microbiota: Blautia, Serratia, and Akkermansia bacteria. They are all found in healthy people, but in cases of prediabetes and diabetes they are present in a far greater quantity.
The researchers were able to link increased levels of bifidobacteria (they are most commonly found in the intestines of breast-fed infants and they are considered to be one of the most important components of microbiota) to a high intake of dietary fibre, or roughage. This corresponds with the results of a previous study of gut microbiota in urban and rural populations in Russia which the same group of researchers were also involved in. During this study it was found that in people living in rural areas of the Tyva Region, levels of bifidobacteria were significantly higher than in residents of other regions: this was presumably due to the fact that the diet of the rural population was based more on natural products and the proportion of "industrial" food with a low fibre content, in contrast, was relatively small.
These findings bring scientists and medical professionals one step closer to understanding the complex reciprocal cause-and-effect relationship between the change in the proportion of certain types of bacteria, metabolic disorders, and diet. As the authors of the paper point out in discussing their findings, one of the possible ways that microbes affect diabetes could be by provoking an immune response - this theory was previously put forward by researchers from Finland.
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The Verge / December 28, 2015
Putin has turned Russia's space agency into a state-run spaceflight corporation
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Подписан указ "Об упразднении Федерального космического агентства". На его базе будет создана Государственная корпорация по космической деятельности "Роскосмос", наделенная функцией уполномоченного органа управления в сфере космической деятельности от имени России.
Russian President Vladimir Putin is dissolving the country's Federal Space Agency, known as Roscosmos, and turning it into a state-run corporation, according to a statement by the Kremlin. That means Roscosmos will transform from a solely government-funded agency into a company that's overseen and partially backed by the government. It allows the organization to pursue the country's overarching space goals while additionally conducting commercial affairs like other private spaceflight companies. The move is meant to fix an agency that has been plagued by corruption and major financial scandals.
The transformation will take effect on January 1st, 2016, thanks to a decree signed by Putin today that finalizes a bill signed into federal law in July. All documents pertaining to the agency's activities will be transferred to the new company, and the powers and functions of the agency should also remain the same, according to the decree. However, Roscosmos will go through some restructuring, and any employees who are let go during the agency's liquidation will be guaranteed "compensation in accordance with the legislation of the Russian Federation."
The decision to dissolve Roscosmos was approved by Putin in January of this year, as a way to shake up an agency that has been dealing with financial scandals, money troubles, and corruption for years. Construction of Russia's next big launch site, the Vostochny Cosmodrome, has been continuously delayed due to budget troubles. And in 2014, it was revealed that Roscosmos committed financial violations totaling more than $1.8 billion, according to Russia's public spending watchdog agency.
Russia's Deputy Prime Minister Dmitry Rogozin said the agency's poorly handled finances are also responsible for many of Russia's spacecraft accidents since 2010, including the failure of a Russian Progress resupply ship earlier this year. "We have uncovered acts of fraud, abuse of authority (and) document forgery," said Rogozin, according to the International Business Times. "With such a level of moral decay, one should not be surprised at the high accident rate."
The transition to a state-run corporation is meant to address these financial issues and improve the agency's management, according to the Kremlin. As a state-run corporation, Roscosmos will be able to compete and strategize with many of the nation's private companies, all while being overseen by Russia's federal government. It's unclear if such a restructuring will be able to salvage Roscosmos, which has ambitious plans of landing humans on the Moon in 2029.
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Reuters / Tue Dec 29, 2015
Russia to rewrite space program as economic crisis bites
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При сокращении общей сметы нового варианта Федеральной космической программы на 2016-2025 гг. изрядно урезали лунную программу, еще недавно считавшуюся стратегической целью развития отечественной космонавтики.
Russia is to revise its space program, the national space agency said on Tuesday after a newspaper published a report that billions of dollars of cuts may be afoot including to ambitious Moon exploration plans.
Several Russian government ministries were engaged in revising the space program up to 2025, Roscosmos said in a written statement to Reuters.
It did not give details. But the Roscosmos statement and a report in Izvestia newspaper suggested Russia's prestigious space program may also have fallen victim to government cutbacks brought on by hard times.
Buffeted by low oil prices, Western sanctions and a falling rouble, the Russian government is in the process of scaling back its spending plans for everything from the health sector to welfare.
The authoritative Izvestia newspaper published details of what it said was a draft proposal sent by Roscosmos to the government which showed big spending cuts were being proposed to the Moon exploration program.
Russian Deputy Prime Minister Dmitry Rogozin announced in April last year that Moscow planned to build a big base on the Moon which he said would serve as a platform for scientific breakthroughs.
Izvestia reported Roscosmos was proposing to cut the manned flights segment of lunar exploration by 88.5 billion roubles ($1.22 billion) to 329.67 billion roubles, but said funding to build a spaceship to fly to the Moon would not suffer seriously.
Roscosmos, in its statement, declined to comment on those figures, saying the revised program was still extensive.
"The revised project of the federal space program for 2016-25 envisages the study of the Moon by automated orbiters, as well as by building up scientific and technical potential for further studies, including by manned missions," it said.
It declined to say whether Russia's plans for a Moon base were still alive, but said the first manned flight around the Moon would not take place before 2029.
President Vladimir Putin has spoken many times of rekindling Soviet-era space glory. The USSR launched the first artificial "sputnik" satellite in 1957, sent the first man into space in 1961, and conducted the first-ever space walk in 1965.
But Cold War rival the United States made six manned landings on the Moon between 1969 and 1972, while the Soviet-built N-1 heavy rocket, designed to take cosmonauts to the Moon, failed to make a single successful flight.
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