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14 ноября 2016, 13:15

DCC to acquire Gaz Europeen

DCC, the Ireland based holding company, agreed to acquire Gaz Europeen in France through its subsidiary DCC Energy to expand its business there. DCC said November 14 it has agreed to acquire 97% of the share capital of Gaz Europeen for €110mn ($118.5mn). According to a filing to stock exchange...

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14 ноября 2016, 11:17

DCC shares jump 8.4% after financial update

This is a Real-time headline. These are breaking news, delivered the minute it happens, delivered ticker-tape style. Visit www.marketwatch.com or the quote page for more information about this breaking news.

03 октября 2016, 15:56

GE Affiliate to Expand Portfolio with DCC to Boost Growth

GE Aviation,a segment of General Electric Company (GE), recently announced its plans to shortly open a digital collaboration center (DCC) in downtown Austin

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15 августа 2016, 15:00

THERE’S A LOT TO WORK WITH IN THESE EMAILS, IF THE GOP HAS ANYONE SMART ENOUGH TO DO IT: Leaked DCC…

THERE’S A LOT TO WORK WITH IN THESE EMAILS, IF THE GOP HAS ANYONE SMART ENOUGH TO DO IT: Leaked DCCC Memo Offers Window into Committee’s Candidate Research.

01 августа 2016, 23:09

Press Gaggle by Principal Deputy Press Secretary Eric Schultz en route Atlanta, Georgia, 8/1/16

Aboard Air Force One En Route Atlanta, Georgia 12:10 P.M. EDT   MR. SCHULTZ:  Welcome aboard Air Force One, everybody, en route to Atlanta, where the President will address the 95th Convention of Disabled American Veterans.  This will mark his final major address to our nation’s veterans.  So the President is looking forward to speaking with these brave men and women today.   The President will make two important announcements -- first, that since 2010, we have reduced veterans’ homelessness by nearly half, and by 17 percent since just last year.  And second, as part of the President’s precision medicine initiative, 500,000 veterans have voluntarily donated their health data to the future of science and medicine through the VA’s Million Veteran Program, marking a critical halfway point to the goal of signing up 1 million veterans.     The President will talk this afternoon about some of the veterans whose stories have deeply moved him over the past eight years.  He'll also discuss the necessary transformation underway at the Veterans Administration, the progress we've made and the work still to be done.     This afternoon, the President will make the case that politicians and policymakers must do more than just pay lip service to caring for our veterans.  He will point to some proposals in Washington that gut funding for veterans’ care or to privatize the Veterans Administration.  The President believes this is a misguided approach and that, as the greatest nation on Earth, we should not leave veterans to fend for themselves.   So I hope you all look forward to the President’s remarks this afternoon.  I'm happy to take questions on that or anything else on your minds.   Q    -- that the President will touch upon politicians’ rhetoric when it comes to our veterans.  Gold Star families have been an important part of this administration and other presidencies, as well.  Over the weekend, Donald Trump made some pretty offensive comments to the Khan family who spoke at the DNC.  Is rhetoric like that appropriate in the Oval Office?  And will President Obama specifically mention those comments in his remarks today?   MR. SCHULTZ:  Stacey, thank you for the question.  I don't have any additional preview of the President’s remarks beyond what I was just able to discuss.  For any response on the campaign trail I'd refer you to -- for any response to back-and-forth on the campaign trail, I would refer you to the campaigns.   I can say, generally speaking, since you mentioned the President’s longstanding support for Gold Star families, I'm happy to tell you about our approach.  As you mentioned, this is something that the President believes should rise above politics; that the sacred covenant we have with the brave men and women who serve our country and those who perform the ultimate sacrifice should be one that we honor every single day.  The President believes that nobody has given more for our country’s security, for our country’s safety, for our country’s freedom than Gold Star families.     This is something, as you point out, he’s expressed in public, but it's also something he’s expressed in private when meeting with families, when grieving with families.  You’ll note that just last week, Sharon Belkofer introduced the President at the Democratic National Convention.  She, herself, is a Gold Star mom who lost her son in a Taliban attack in Afghanistan a few years ago.  The President was deeply moved by her introduction and took enormous pride in her remarks that evening.  So the President believes that Sharon’s family and families all across this country who’ve made the ultimate sacrifice deserve nothing but honor and gratitude for their sacrifice.   The President has expressed that before.  But in terms of what his remarks will say today, I'd encourage you to tune in.   Q    Separate from the ongoing campaign and any specific person who may or may not have said anything, would President Obama, as he is leaving office, support or stand by these types of comments being made by someone who could take his place next year?   MR. SCHULTZ:  Well, again, I do believe the President’s views on this are well-known, which is families who made the ultimate sacrifice for this country’s freedom and this country’s safety deserve nothing but our country’s honor and gratitude and deepest respect.     Q    How do you respond, or how does the administration respond to critics who say that the problems at the VA got worse, not better, during the President’s first term, and that the efforts that he’s making now essentially amount to tinkering around the edges and not the complete overhaul that they say the place requires, including more privatization, seeing private doctors, et cetera?   MR. SCHULTZ:  Mike, I'm glad you asked that question, because this President has made it a priority to transform the Veterans Administration.  That began many years ago, and an important milestone for that was bringing in Secretary Bob McDonald, who has an esteemed record in the private sector in terms of making sure organizations and businesses and large bureaucracies run better.  That was the mandate given to Secretary McDonald when he took the oath of office to run the Veterans Administration.  That's something the Secretary has made enormous progress on.   But if you're suggesting that there’s more work to be done, the answer to that is absolutely.  But I do reject the notion that we're just tinkering around the edges.  To the contrary.  At the President’s direction, Secretary McDonald has initiated a transformation at the VA that begins with how they deploy their care and services, but also includes how they track service and care, how they hold themselves accountable, how they protect whistleblowers instead of shunning them.   So the President and Secretary McDonald have both been very clear, they want as much transparency and accountability at the VA as possible.  Again, we've made remarkable success.  The idea that we could cut veterans’ homelessness in half was an idea I think many people would say is far-fetched.  This has been a problem in this country for decades, what some called intractable years ago.  The President is proud of the progress we've made on that.   But like you said, we're not done.  We've got a lot of work to go.  I think the President is going to speak to this exact challenge this afternoon.     Q    Can you confirm, as the Libyan government announced today, that the U.S. has begun airstrikes against Islamic State targets in Libya?   MR. SCHULTZ:  Darlene, I think the Department of Defense -- we might have lifted off by this point -- but the Department of Defense did confirm that at the request of the Libyan Government Of National Accord, the U.S. military conducted precision airstrikes against ISIL targets in Sert, Libya to support the GNA-affiliated forces seeking to defeat ISIL in its primary stronghold inside Libya.     I can tell you that these strikes were authorized by the President at the recommendation of Defense Secretary Carter and is consistent with our overall approach of combatting ISIL, which is principally to work with capable and motivated local forces.   We've seen GNA-affiliated forces on the ground in Libya recapture territory from ISIL recently, and these strikes were intended to help support those forces as they continue to make progress.     Broadly speaking, these strikes are consistent with our overall approach -- as you've seen, we've had significant impact on going after ISIL in Iraq and Syria.  I believe the latest statistics from the Department of Defense include that we've recaptured -- the coalition forces have recaptured about 50 percent of ISIL's territory in Iraq and about 25 percent of ISIL's territory in Syria.  But we've always been clear that the threat posed by ISIL extends beyond those two countries.  The President has been clear that he will deny any safe haven to groups like ISIL or terrorists who wish to do us harm, and that's why the strikes you've seen are consistent with that approach.   Q    Are the strikes sort of a one-and-done kind of thing or will there be more?     MR. SCHULTZ:  Well, I don’t want to preview any additional military action for you, but these types of precision strikes were approved by the President earlier at the request of the Defense Secretary.  I will say that U.S. assistance will be limited to strikes and information sharing.  There are unique capabilities that our military can provide to support forces on the ground, and that's what the President wanted to do.   Q    Governor Scott said that the number of Zika cases has risen to 14 in Florida.  Stipulating that, of course, you want Congress to do more -- we don't need to hear that whole thing again -- but he'd asked specifically for a federal emergency response team and so I'm wondering if you could respond to the Governor's request.    MR. SCHULTZ:  Thank you, Justin.  The President is, as we mentioned on Friday, continually getting briefed on the situation in south Florida.  I know that Governor Scott made that request, and we are -- that team is being deployed by the CDC in short order so we’ll be able to work with Governor Scott’s team on the ground in south Florida.   Like you said -- or like we’ve talked about recently, the Governor has said they’re working this aggressively.  They are redoubling their vector control in the area.  They’re testing both mosquitoes and people.  And they’re closely monitoring and committed to making adjustments to their protocol as necessary.   They’re doing all of this with the support of the CDC at the federal level.  As we’ve said, we’ve deployed -- the CDC has given out $2 million in specific Zika response funding, and also $27 million in emergency preparedness funding, much of which can be used for their response to this.  This disbursement of funds is on top of other pieces that have been mobilized in the federal government to respond.  The Department of Health and Human Services, they are assisting local governments all across the country on vector control.  They continue to expand their efforts on research and vaccine development.   Unfortunately, as we’ve seen, vaccine development is one of the areas that has been slowed because Congress has not funded this response.  Unfortunately, Congress left town for about seven weeks without doing anything.  Congress left town about four months after the United States -- the Obama administration submitted a request for $1.9 billion worth of funding.  That wasn’t a number that we pulled out of thin air.  That was a number that was developed based on our public health professionals and our experts telling us what the United States government would need to fully fund a response to this effort.   So if anything, we hope that this provides a wake-up call to members of Congress that when they get back to Washington from their vacation, they can get to work on addressing this problem.   Q    There was a Russian military helicopter that was shot down in Syria.  I’m wondering if you can confirm whether or not it was working on a humanitarian mission.  What impact do you think it will have on the peace talks and whether or not it will impact the sort of safe corridors that they’re trying to set up for humanitarian access?   MR. SCHULTZ:  Justin, I saw public reports on this.  I know that Russian officials have spoken to it.  I don’t think we’ll have too much to add from here other than to express regret for any loss of life in association with this conflict.  That’s, frankly, why we’ve been working tirelessly on a political solution.  We believe that there is no military solution to this crisis.  That’s why Secretary Kerry has been our principal diplomat, working with his counterpart in Russia, Foreign Minister Lavrov, in order to make some progress on the political solution inside Syria.   Q    Russian officials said today that basically -- that the accusations that they were involved in the hacking of the DNC or the DCC are basically just a cover or a way to distract from the fact that there’s actually been domestic tampering with the campaign, and basically accusing, I guess, the U.S. of trying to use them as a scapegoat.  I was wondering, did you have any response to that?  And then also, if the Russians or if a state actor is involved in these hacks -- I know you kind of dealt with this before -- but what is the administration considering as a way to respond?  What is the appropriate response to these types of hacks if they’re being carried out by other state actors?   MR. SCHULTZ:  Ayesha, I’ll address a couple points there.  First, the FBI is still investigating this matter, so it’s important that I not get ahead of that investigation.  So we’re going to wait for that investigation to conclude.  They will also make a determination if it’s appropriate to publicly implicate the culprit.  That’s a decision that will be made by the FBI and our national security officials to determine if that’s in the U.S.’s best interest, to make that public declaration.   I would refer you to the Director of National Intelligence  -- James Clapper actually spoke to this late last week.  He said that there’s “a host of usual suspects out there that engage in this sort of activity.”  But the FBI is still investigating, and if there’s a point where they determine who was responsible for this attack and that it’s in the United States’ best interest to make that conclusion public, that they’ll be the first to do so.   So I don't have any updates on the investigation for you.  We do know -- and the President has spoken to this -- that Russia has a record of engaging in this activity.  You don't have to take my word for that.  That's something that's been expressed by our national security officials for many years now.  That's something we've been tracking for a while.  Admiral Mike Rogers of Cyber Command, in testimony before the Senate Armed Services back in April -- that was before this latest back-and-forth -- he said that "Russia has very capable cyber operators who can and do work with speed, precision and stealth.  Russia is also home to a substantial segment of the world's most sophisticated cybercriminals who have found victims all over the world."   So as we've also mentioned, Secretary Kerry raised this in a meeting with Prime Minister Lavrov, I think two weeks ago now.  That's again because, unfortunately, Russia has a bad record when it comes to this type of activity.  But I don't have any actions to preview for you that would come after the FBI makes a conclusion on its investigation.   Q    Will there be consideration of bringing a criminal case or doing -- I mean, or some type of retaliation or, I guess, sanctions?     MR. SCHULTZ:  Again, I want to be very clear, I cannot get ahead of the FBI investigation into this specific matter.  I can say, generally speaking, if you look at how the United States has responded to intrusions by state actors into cyber infrastructure within the United States, there's a whole host of options available to us.  That includes economic sanctions that would be housed at the Department of Treasury, and that does include law enforcement measures that could be taken out of the Department of Justice.   Q    I have just one other one on veterans.  In 2010, when the President announced -- he said that he wanted to eliminate veterans’ homelessness by 2015.  And today, he is going to say that it's been cut almost in half.  Can you speak a little bit to why we're not at zero, as he intended or wanted?   MR. SCHULTZ:  That's a totally fair question and this is a goal that's extraordinarily important to the President.  And when he set that goal, he knew it was ambitious and he knew it was a daunting task.  It was a problem that has escaped administrations of both parties for many decades.  Quite frankly, it's a problem that has been elusive to governors and mayors across the board for many years.  But that didn't deter the President from wanting to make this a priority.   So we're proud of the progress that we've made over the last few years.  Like I said, we've now cut that number in half.  We've actually cut it by 17 percent in just the last 12 months. So the President is proud of the progress we've made.  But you are absolutely correct to point out that there's still work to be done.  And I expect the President to address this head on this afternoon in Atlanta.   Q    There are hundreds more that were either arrested or dismissed from their jobs in Turkey over the weekend.  At what point does your guys' refusal to explicitly condemn this turn into condoning it in some way?   MR. SCHULTZ:  Well, Justin, I want to be very clear.  We have unequivocally condemned the failed coup in Turkey.     Q    -- that's not what I'm asking.   MR. SCHULTZ:  We fully support the democratically elected government in Turkey.  The President has conveyed that privately and we've expressed that publicly.  What we've also said publicly is that we believe that Turkey must respect its democratic institutions; that freedom of the press, freedom to protest, freedom of speech are enshrined in the Turkish constitution and, quite frankly, that's just not in the United States' best interest, that's in the best interest of the people of Turkey -- that when we respect democratic institutions, that strengthens society as a whole.   So the President hasn't wavered on that at all.  The President believes that the country of Turkey was shook by a failed coup by its military leadership, and so it's going to take some time to work through that.  But as they do, the President has been crystal-clear that they should do so in a way that also respects civil liberties and the strong traditions of democratic institutions.   Q    So you would say that President Erdogan's actions have sort of surpassed those strong institutions or gone contrary to democratic values?   MR. SCHULTZ:  I would say the Turkish government understands the U.S. position, which is, in order to move past this challenging time, they have to do so recognizing that one of their strengths as a country is their respect for democratic institutions.  That includes freedom of the press, freedom to gather, freedom of speech, freedom of expression.  And the only way to honor the Turkish constitution is to respect those principles.   Thank you, guys.   END  12:31 P.M. EDT  

15 июля 2016, 13:53

Research Review | 15 July 2016 | Portfolio Analysis

Asset Allocation: A Recommendation for Resolving the Collision between Theory and Practice Larry J. Prather (Southeastern Oklahoma State University), et al. April 26, 2016 We examine the creation of a low-cost optimal risky portfolio that individual investors can easily construct and manage. We consider five index mutual funds and three precious metals that are easy […]

08 июня 2016, 15:15

4 European Funds in Focus on Brexit Possibility

In a plebiscite on June 23, votes in favor or against of Brexit will be requested. This will decide the fate of the nation in the future.

18 мая 2016, 09:18

Европейские рынки акций снизились во вторник

Европейские фондовые индексы увеличились по итогам торгов во вторник, исключением стал британский рынок.

12 мая 2016, 18:17

The 4 Best Hidden Credit Card Features

In any discussion of credit cards, bonuses, points, and miles appear center stage. However, there are many more money-savings perks cardholders can be taking advantage of. The only problem is that in order to use them, you have to know they exist. We scoured the land and read through hundreds of terms of service contracts to find the absolute best hidden credit card benefits available to most consumers. Travel Insurance. Some of the top travel credit cards come with benefits that can protect your finances in the event your trip is cancelled. When Eyjafjallajökull, the Icelandic volcano, erupted in 2010, over 95,000 flights across Europe were cancelled, affecting an estimated 10 million travelers. It doesn't always take a giant volcanic eruption to cause us to miss hotel reservations or flights - everything from family sickness to inclement weather can be the culprit. Through this benefit, you can be reimbursed for any missed flights or hotel reservations, so long as it happened due to a covered reason. Small Print Warning: Coverage varies greatly between different cards, so you should always familiarize yourself with your policy before deciding to rely on it. You can request your issuer to send you a copy of your cardmember benefits. These should outline any travel insurance benefits you can qualify for. In some cases, your network (Visa, Amex, Mastercard, etc.) are the ones to provide the benefit. If that's the case, you will need to contact them instead. Price Protection. Many shopaholics have experienced this nightmare scenario: you buy an item, and a few weeks later that same item goes on sale. What few people are aware of is that if you charged that purchase to a credit card, you may be eligible to receive a refund equal to the price difference. Mastercard, Discover, Citibank, and select Visa credit cards come with this benefit. If an item you charge to a card has its price lowered within 60-90 days of the transaction, you can file a claim to be reimbursed the difference. Typically you shouldn't expect to receive more than $250 - $500 per claim, and note that there are limits on total payouts available within a single calendar year. Small Print Warning: There is a large number of items that won't be covered by price protection. Items purchased through online retailers like Amazon, jewelry, art, "limited quantity" or "going-out-of-business" sales, are all not covered. The exact list of exceptions will be different card-to-card, so as with all of these secret perks, you're best is to read through your cardmember agreement. Bonus Malls. Most people know about their credit card's reward structure. You may, for example, get 3 points per $1 on gas, 2 points on groceries, and so on. If you want to get even more rewards out of the money you spend, considering using shopping through online bonus malls. Many of the nation's top banks provide special online shopping portals through which cardmembers can earn extra points on every dollar you spend. The prices on these are generally the same ones you'd find in stores, so you won't be paying a premium for earning your extra miles. You can access bonus malls by logging into your online account or by searching for them on google. Personal Finance Tip: Bonus malls have a dangerous side to them. If you get caught up in earning points, you may end up buying things needlessly. You should always approach bonus malls with a rational mindset. Only look for items that you were already planning on buying or absolutely need. If you end up buying things recklessly, you may wake up one day with an out of control balance. Automatic Currency Conversion. When you use your credit card abroad, your bill will still be charged in United States Dollars (USD). This happens because, at the time of your transaction, the credit card network will convert the the price from the local currency to USD. Generally speaking, Visa and Mastercard will give fair exchange rates. These currency conversion rates are much better than what you can find in certain exchange offices. In some cases, the price disparity is so great that you will still come out ahead, even if your card has the typical 3% foreign transaction fee. Personal Finance Tip: Avoid dynamic currency conversion (DCC) like the plague. Some foreign merchants may offer you to convert the currency for you, and charge you in USD. The claim here is that you will avoid the foreign transaction fee by doing so. However, in practice, we found merchants are likely to pick exchange rates that benefit their home currency, and therefore increase your cost. -- This feed and its contents are the property of The Huffington Post, and use is subject to our terms. It may be used for personal consumption, but may not be distributed on a website.

07 апреля 2016, 23:34

На борту революционного стелс-эсминца США Zumwalt: путешествие в «будущее»

Американское издание Defense News опубликовало эксклюзивный материал Кристофера П. Каваса – первого журналиста, побывавшего на борту революционного эсминца ВМС США Zumwalt (DDG 1000), называемого экспертами «линкором XXI века». Как сообщал ранее Newsader, с технологической точки […]

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06 апреля 2016, 10:34

Volkswagen взбодрит российский рынок двумя новинками

Volkswagen порадует российских автолюбителей двумя новыми моделями на базе Passat. Старт продаж уже объявлен официальным представительством в РФ. Volkswagen Passat теперь доступен для заказа в двух вариантах кузова универсал. Это модели Variant и Alltrack.

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02 июля 2014, 03:44

Как белок нетрин подсказывает аксонам, куда им расти

Как белок нетрин подсказывает аксонам, куда им расти Рис. 1. «Портрет героя». Структура свободного нетрина-1 с двух сторон. LN-домен показан голубым, LE-1 (первый модуль LE-домена) — зеленым, LE-2 — розовым, LE-3 — красным, LC не показан вовсе. Во врезке — связывание участка LN-домена с ионом кальция, необходимое для достижения нетрином правильной конформации. Буквы и цифры обозначают аминокислоты и их порядковые номера в белке. Изображение из обсуждаемой статьи в Science Клетки общаются друг с другом с помощью химических сигналов. Выделяя те или иные вещества, клетка может «подзывать» к себе другие клетки либо «отпугивать» их, сообщать им различные сведения, «звать на помощь» клетки иммунной системы в случае атаки патогенов. Химическое общение между клетками играет важнейшую роль во множестве клеточных процессов. Мы рассмотрим подробно один из таких процессов — аксональное наведение — и роль в нем «химической подсказки» — белка нетрина. Связываясь с разными рецепторами, нетрин образует совершенно разные комплексы, что приводит к разным каскадам реакций, которые могут по-разному поворачивать конус роста аксона. Аксональное наведение — это сложный процесс, в результате которого аксон прорастает в нужное место, а не куда попало. Нечего и говорить о том, какая тут нужна точность — представьте себе, например, путешествие аксона от спинного мозга до пятки. Или — менее наглядный, но более важный пример — образование правильных связей между нейронами в головном мозге, без которого мозг работать не будет (о том, насколько это сложно, запутанно и интересно, можно прочесть в статье Blue Brain Project: как все связано?). Самый кончик аксона — конус роста — чрезвычайно подвижное и, можно сказать, любопытное образование. Он нашпигован рецепторами к так называемым «химическим подсказкам» — веществам, которые окружают аксон снаружи и сообщают, куда ему расти. Предполагается, что связывание рецептора на конусе роста с химической подсказкой вызывает каскады реакций, приводящие к перестройке цитоскелета и повороту конуса роста — а значит, к изменению направления роста аксона. Так и представляешь себе, как конус роста «ловит» сигналы от разных подсказок, вертится из-за этого в разные стороны и наконец, выбрав итоговое направление, поворачивает туда весь аксон. Химические подсказки могут находиться на поверхности окружающих аксон клеток или выделяться этими клетками в окружающую среду. Если они прикреплены к поверхности клеток, то могут действовать только при непосредственном соприкосновении этих клеток и конуса роста; если же они выделяются в окружающую среду, то дальность их действия повышается. Большинство химических подсказок играет роль не только в аксональном наведении, но и в других процессах, например в прорастании кровеносных сосудов — ангиогенезе. Есть несколько классов химических подсказок: Семафорины (от слова «семафор») — могут как выделяться окружающими нейрон клетками, так и находиться на их поверхности. Они в основном отталкивают, «отпугивают» аксоны, не позволяя им прорасти в неподходящие для этого области. Нетрины (от санскритского «netr» — проводник) — выделяются окружающими аксон клетками и могут как привлекать аксоны, так и отпугивать их. Слиты (см. Slit-Robo) — выделяются окрестными клетками и, связываясь с Robo-рецепторами, отпугивают аксоны. Эфрины — находятся на поверхности окружающих аксон клеток. Эти молекулы-перевертыши могут быть одновременно и лигандами, и рецепторами. Соединяясь с эфриновыми рецепторами на конусе роста, они могут как привлекать, так и отпугивать нейроны; в то же время, соединение их с этими самыми эфриновыми рецепторами может приводить и к изменениям внутри тех клеток, на поверхности которых находятся сами эфрины. Молекулы клеточной адгезии — находятся на поверхности почти всех клеток организма и связывают их друг с другом и с внеклеточным матриксом. Они важны не только для аксонального наведения, но и для множества других процессов: без них наш организм вообще распался бы на отдельные клетки. А также другие, чуть менее специализированные молекулы.   Как вы уже, наверное, заметили, некоторые из вышеописанных молекул выполняют только одно действие — например, только отпугивают аксон, в то время как другие умеют и привлекать, и отпугивать аксоны в зависимости от конкретных условий, прежде всего от наличия на поверхности конуса роста тех или иных рецепторов. В результате аксон, на конусе роста которого находятся «привлекательные» рецепторы к этой молекуле, прорастет туда, где находится данная химическая подсказка, а аксон, на конусе роста которого рецепторы «отталкивающие», будет избегать места с этой подсказкой как чумы. Причем вокруг конуса роста много разных подсказок, а на самом конусе много разных рецепторов, и в результате все полученные сигналы суммируются, и аксон прорастает туда, куда ему показывает итоговый вектор. Большая интернациональная группа ученых задалась целью подробней исследовать один из классов химических подсказок — нетрины — и разобраться на молекулярном уровне, как этим молекулам удается так противоположно действовать на аксоны. Сама по себе работа не представляет особого интереса для широкой публики, но на ее примере хорошо видны правила, по которым взаимодействуют друг с другом белки, и то, как эти взаимодействия могут влиять на жизнь клетки. Белок состоит из отдельных доменов — функциональных групп, имеющих сложную третичную структуру, — и соединяющих их линкерных участков — цепочек аминокислот, почти не имеющих никакой структуры и представляющих собой как бы веревочку между двумя доменами. У разных белков отдельные домены могут быть почти одинаковыми и выполнять сходные функции. Существуют базы данных по белковым доменам (например, pfam и scop). Как правило, домен получает название по тому белку, где впервые был обнаружен, либо по тому, на котором был исследован лучше всего; часто название домена не имеет никакого отношения к его функции. Сочетание доменов, их порядок и длина линкерных участков между ними во многом определяют итоговые свойства белка. Связывание домена с другим доменом этого или другого белка либо с какой-то небольшой сигнальной молекулой может кардинально изменить его свойства, а также свойства всего белка. Изменение этих свойств может вызвать лавинообразные каскады реакций, приводящие к серьезным перестройкам жизни клетки. В работе рассматривались: Нетрин-1 (рис. 1) — один из главных нетринов. У мыши состоит из 603 аминокислот, у человека — из 604. Имеет три домена — ламининовый N-концевой, или LN (см. Laminin N-terminal); ламининовый EGF-подобный (см. EGF-like domain), состоящий из трех модулей, посередине; и маленький положительно заряженный LC-домен на C-конце. DCC — его «привлекательный» рецептор. Связывается с LN-LE доменами нетрина-1 посредством своих фибронектиновых доменов III типа (см. Fibronectin type III domain). Неогенин (см. статью N. H. Wilson, B. Key, 2007. Neogenin: One receptor, many functions) — многофункциональный рецептор, имеющий некоторое структурное сходство с DCC. Возможно, играет роль и в аксональном наведении за счет связывания с нетрином-1. Unc5 — «отталкивающий» рецептор нетрина-1. Нетрин-1 образует тетрамерный комплекс с неогенином Одна молекула нетрина в принципе не в состоянии связаться с одной молекулой неогенина: линкер между нетринсвязывающими доменами неогенина не может так растянуться, чтобы прилипнуть к нужным доменам нетрина. Поэтому нетрины-1 образуют с рецепторами комплексы, в которых несколько нетринов связываются с несколькими молекулами рецепторов. Комплекс, который нетрин-1 образует с неогенином, состоит из двух молекул нетрина и двух молекул рецептора. Нетрин при этом практически не меняет свою конформацию по сравнению со свободным состоянием. Два нетрина встают крест-накрест и сцепляются своими срединными LE-2 доменами, а к их концам присоединяются два параллельно расположенных неогенина (рис. 2).   Рис. 2. Связывание нетрина-1 с неогенином в тетрамерный комплекс (А). Во врезках подробнее показаны образующиеся связи: между LN-доменом нетрина и FN4-доменом неогенина (две связи в двух концах комплекса, В), между LE3-доменом нетрина и FN5-доменом неогенина (тоже две связи в двух концах комплекса, С) и, наконец, между двумя LE2-доменами двух нетринов (одна связь в самой середине комплекса, D). Изображение из обсуждаемой статьи в Science Нетрин-1 связывается с DCC У DCC линкерный (соединяющий два домена) регион между доменами FN4 и FN5 короче, чем у неогенина, и потому он не может связываться с нетрином-1 в такой красивый тетрамерный комплекс, как неогенин. Вместо этого нетрины и DCC чередуются в длинных (теоретически — бесконечных) цепочках (рис. 3). При этом молекулы DCC в этих цепочках расположены параллельно друг другу, так же, как и молекулы неогенина в вышеописанном комплексе.   Рис. 3. Комплекс между нетрином-1 и DCC (А). Во врезках (В и С) сравниваются связи, образуемые одинаковыми доменами нетрина с DCC и нетрина с неогенином. Видно, что образуемые связи практически идентичны; но из-за более короткого линкера DCC не может образовать с нетрином такую же тетрамерную структуру, как неогенин, а образует вместо этого длинную-длинную цепочку (D). Изображение из обсуждаемой статьи в Science Другие возможности Исследователи предположили, что, поскольку связи между нетрином-1 с DCC и нетрином-1 с неогенином практически идентичны, возможна ситуация, когда нетрин одним концом сцепляется с одним своим рецептором, а другим — с другим. Кроме того, не будем забывать и об «отталкивающем» рецепторе для нетрина-1 — Unc-5. Судя по всему, он присоединяется к LE2-домену нетрина (см. статью R. P. Kruger et al., 2004. Mapping Netrin Receptor Binding Reveals Domains of Unc5 Regulating Its Tyrosine Phosphorylation). В результате помимо двух вышеописанных структур могут получаться другие, в которых нетрины, неогенины, DCC и UNC5 слипаются друг с другом в самых причудливых сочетаниях, что приводит к самым разнообразным последствиям: различные изменения конформации рецептора приводят к разным каскадам реакций, которые могут совершенно по-разному поворачивать конус роста аксона. Похожим образом могут работать и другие сигнальные молекулы, чьи эффекты отличаются в зависимости от того, на какие рецепторы им довелось попасть. Источник: Kai Xu, Zhuhao Wu, Nicolas Renier et al. Structures of netrin-1 bound to two receptors provide insight into its axon guidance mechanism // Science. 2014. V. 344. P. 1275–1279. Вера Башмакова

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10 февраля 2014, 09:00

Resettlement policy framework

The objective of the Dhaka Water Supply and Sanitation Project for Bangladesh is to improve water supply, sewerage disposal, and sanitation and storm water drainage facilities in Dhaka and Chittagong. Some of the negative impacts and their mitigation measures are: 1) before taking possession of acquired lands and structures and before start of civil works construction, project affected peoples (PAPS) will be paid compensation and other assistance in full. Where PAPS are entitled to relocation, the relocation site will be fully developed before the PAPS are displaced. Dhaka Water Supply and Sanitation Authority (DWASA) will ensure that the standard of living of all affected persons is restored to the level enjoyed before the commencement of the project, and, if possible, improved; 2) in case direct purchase by DWASA is not possible (or permitted), all acquisition of land will be under Land Acquisition Act 1982, and following the provisions of this policy framework which provides compensation for properties to be acquired and support to be extended for meeting replacement value of the property. Under the Land Acquisition Act compensation are assessed, and paid, by Dhaka City Corporation (DCC) office to PAPS for each mouza where his/her assets are located. Such Compensation Under Law (CUL) that includes 50 percent premium on assessed values does not fully meet replacement cost. DWASA will top-up these amounts to make up for the balance so that the total amounts paid to PAPS are at replacement cost; 3) lack of ownership does not imply lack of compensation rights. The presence of squatters poses particular challenge to DWASA as many of the canals that are likely to be included in the project have large number of squatter settlements along the banks. The lack of legal tenure to land or assets will not be regarded as a criterion for withholding financial compensation or assistance in relocation in the project. DWASA would strive to provide suitable alternatives to resettle displaced squatter communities. The affected squatters would be carefully screened to ensure that resettlement and rehabilitation assistance are provided only to vulnerable families and that well to do squatters, encroachers and musclemen (mastaans) are screened out; and 4) large number of potential displacement of squatters poses particular challenge to DWASA. DWASA will explore all possible housing options to relocate severely affected/displaced squatters to minimize long-term social and economic impacts of displacement and to enable them to restore their livelihood and incomes levels within least possible time.

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27 ноября 2013, 01:06

Array

Deep convective clouds (DCCs) play a crucial role in the general circulation, energy, and hydrological cycle of our climate system. Aerosol particles can influence DCCs by altering cloud properties, precipitation regimes, and radiation balance. Previous studies reported both invigoration and suppression of DCCs by aerosols, but few were concerned with...

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05 октября 2013, 11:00

11 брендов мобильной связи, которых больше нет

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DCC, UMC, Ace&Base и другие динозавры мобильного нейминга

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01 октября 2013, 22:57

Array

The essential process of dosage compensation equalizes X-chromosome gene expression between Caenorhabditis elegans XO males and XX hermaphrodites through a dosage compensation complex (DCC) that is homologous to condensin. The DCC binds to both X chromosomes of hermaphrodites to repress transcription by half. Here, we show that posttranslational modification by...

23 мая 2013, 08:00

The project Southern Africa Trade and Transport Facilitation Project has changed to Active

The project Southern Africa Trade and Transport Facilitation Project has changed to Active. To see more information, see the project information in the World Bank project database The objective of the Southern Africa Trade and Transport Facilitation Program Project for Tanzania is to facilitate the movement of goods and people along the north-south corridor (NSC), whilst supporting improvement in the services for Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) and road safety. The project has 4 components. (1) Improvement of physical infrastructure component will rehabilitate and upgrading of the 137.9 km Mafinga-Igawa road section of the Dar es Salaam corridor in Tanzania; improve of infrastructure and operations at the Songwe/Kasamulu border crossing on the Tanzania/Malawi border; and construction of a one-stop inspection station (OSIS) at Vigwaza and at two other locations in Tanzania. (2) Mitigation of social costs component will undertake road safety and HIV/AIDS initiatives on the corridor. (3) Implementation assistance and additional institutional support component will provide necessary project management and implementation assistance to the implementation unit(s), together with capacity building and requested training. (4) Improved corridor management and monitoring component will be used to support the strengthening of the Dar es Salaam Corridor Committee (DCC) and the funding of its operating costs for a finite period, until a sustainable financing proposal has been introduced. It will also include the establishment of a Corridor Performance Monitoring System (CPMS), to enable the management and monitoring of performance on the corridor.

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05 мая 2013, 13:54

Отрава для Киевской Руси.

Внимание! американская корпорация Монсанто хочет построить свой ​​завод по производству ГМО-СЕМЯН в Украине! Пока планируют в Виннице, но имеются запасные варианты. 29 апреля в Виннице должен состояться городской тендер на приобретение Монсанто 60-80 га нашей родной земли! Земляки, ПОМОГИТЕ!БОЙКОТ присутствию МОНСАНТО В УКРАИНЕ: что нужно делать:1. максимально везде распространять эту информацию.2. выйти на различные медиа, чтобы они подняли волну протеста.3. подключить экологические организации.4. подключите знакомых, политиков, общественных деятелей, знаменитостей.Екологи та аграрії проти розміщення заводу "Монсанто" у ВінниціДля тех кто не понимает в чем зло этой корпорации и во что она превратит земли, рекомендуем посмотреть:Мир согласно "Монсанто"

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26 февраля 2013, 15:50

DCC to move listing to London

Blow to Dublin as energy and distribution group announces plan to seek admission to the FTSE in a bid to help increase awareness internationally

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04 февраля 2013, 12:09

Австралийский регулятор обвиняет Visa в нарушении прав потребителей

Австралийская комиссия по защите потребителей и конкуренции обратилась в федеральный суд с иском против платежной системы Visa, которая, как считает регулятор, ограничивает доступ к услуге моментальной конверсии валюты (Dynamic Currency Conversion, DCC), сообщает агентство Bloomberg со ссылкой на электронное письмо регулятора.