903 resultados para Force balance system
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The atomic force microscope (AFM) was used to continuously follow height changes of individual protein molecules exposed to physiological stimuli. A AFM tip was coated with ROMK1 (a cloned renal epithelial potassium channel known to be highly pH sensitive) and lowered onto atomically flat mica surface until the protein was sandwiched between AFM tip and mica. Because the AFM tip was an integral part of a highly flexible cantilever, any structural alterations of the sandwiched molecule were transmitted to the cantilever. This resulted in a distortion of the cantilever that was monitored by means of a laser beam. With this system it was possible to resolve vertical height changes in the ROMK1 protein of ≥0.2 nm (approximately 5% of the molecule’s height) with a time resolution of ≥1 msec. When bathed in electrolyte solution that contained the catalytic subunit of protein kinase A and 0.1 mM ATP (conditions that activate the native ion channel), we found stochastically occurring height fluctuations in the ROMK1 molecule. These changes in height were pH-dependent, being greatest at pH 7.6, and lowering the pH (either by titration or by the application of CO2) reduced their magnitude. The data show that overall changes in shape of proteins occur stochastically and increase in size and frequency when the proteins are active. This AFM “molecular-sandwich” technique, called MOST, measures structural activity of proteins in real time and could prove useful for studies on the relationship between structure and function of proteins at the molecular level.
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Salmonella spp. have evolved the ability to enter into cells that are normally nonphagocytic. The internalization process is the result of a remarkable interaction between the bacteria and the host cells. Immediately on contact, Salmonella delivers a number of bacterial effector proteins into the host cell cytosol through the function of a specialized organelle termed the type III secretion system. Initially, two of the delivered proteins, SopE and SopB, stimulate the small GTP-binding proteins Cdc42 and Rac. SopE is an exchange factor for these GTPases, and SopB is an inositol polyphosphate phosphatase. Stimulation of Cdc42 and Rac leads to marked actin cytoskeleton rearrangements, which are further enhanced by SipA, a Salmonella protein also delivered into the host cell by the type III secretion system. SipA lowers the critical concentration of G-actin, stabilizes F-actin at the site of bacterial entry, and increases the bundling activity of the host-cell protein T-plastin (fimbrin). The cellular responses stimulated by Salmonella are short-lived; therefore, immediately after bacterial entry, the cell regains its normal architecture. Remarkably, this process is mediated by SptP, another target of the type III secretion system. SptP exert its function by serving as a GTPase-activating protein for Cdc42 and Rac, turning these G proteins off after their stimulation by the bacterial effectors SopE and SopB. The balanced interaction of Salmonella with host cells constitutes a remarkable example of the sophisticated nature of a pathogen/host relationship shaped by evolution through a longstanding coexistence.
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Este trabalho apresenta e compara alguns meios para o estudo do comportamento dinâmico de uma lavadora de roupas de eixo vertical durante o processo de extração de água das roupas, também conhecido como centrifugação. Os três métodos utilizados para estudar o comportamento dinâmico de uma lavadora de roupas de eixo vertical foram: analítico, experimental e simulação através de multicorpos. O interesse nesta etapa é devido ao fato dos problemas de vibração de uma lavadora ocorrerem principalmente durante a centrifugação. A modelagem de uma lavadora de roupas durante a etapa de centrifugação permite a obtenção de seu comportamento dinâmico bem como de suas principais características. Um outro tópico estudado neste trabalho foi o fenômeno de deslocamento da lavadora, um dos principais motivos de reclamação dos usuários de lavadoras de roupa automáticas.
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U.S. Air Force installations by virtue of their isolation and often remote locations provide protection to critical habitats that would otherwise be susceptible to development and other stressors. While Air Force activities may not always compliment environmental protection, a balance between environmental protection and Air Force requirements must be achieved to minimize conflict. Special Area Management Plans (SAMPs) are a possible solution in the quest to balance conservation with mission requirements. Beale Air Force Base, California is the first military installation to pursue implementation of a SAMP. This project found that SAMP implementation could be a tool to successfully balance conservation efforts with military requirements on other Air Force installations; however, further education on the SAMP process would be required.
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The present is marked by the availability of large volumes of heterogeneous data, whose management is extremely complex. While the treatment of factual data has been widely studied, the processing of subjective information still poses important challenges. This is especially true in tasks that combine Opinion Analysis with other challenges, such as the ones related to Question Answering. In this paper, we describe the different approaches we employed in the NTCIR 8 MOAT monolingual English (opinionatedness, relevance, answerness and polarity) and cross-lingual English-Chinese tasks, implemented in our OpAL system. The results obtained when using different settings of the system, as well as the error analysis performed after the competition, offered us some clear insights on the best combination of techniques, that balance between precision and recall. Contrary to our initial intuitions, we have also seen that the inclusion of specialized Natural Language Processing tools dealing with Temporality or Anaphora Resolution lowers the system performance, while the use of topic detection techniques using faceted search with Wikipedia and Latent Semantic Analysis leads to satisfactory system performance, both for the monolingual setting, as well as in a multilingual one.
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The magnetization reversal of two-dimensional arrays of parallel ferromagnetic Fe nanowires embedded in nanoporous alumina templates has been studied. By combining bulk magnetization measurements (superconducting quantum interference device magnetometry) with field-dependent magnetic force microscopy (MFM), we have been able to decompose the macroscopic hysteresis loop in terms of the irreversible magnetic responses of individual nanowires. The latter are found to behave as monodomain ferromagnetic needles, with hysteresis loops displaced (asymmetric) as a consequence of the strong dipolar interactions between them. The application of field-dependent MFM provides a microscopic method to obtain the hysteresis curve of the array, by simply registering the fraction of up and down magnetized wires as a function of applied field. The observed deviations from the rectangular shape of the macroscopic hysteresis loop of the array can be ascribed to the spatial variation of the dipolar field through the inhomogeneously filled membrane. The system studied proves to be an excellent example of the two-dimensional classical Preisach model, well known from the field of hysteresis modeling and micromagnetism.
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A hydrological–economic model is introduced to describe the dynamics of groundwater-dependent economics (agriculture and tourism) for sustainable use in sparse-data drylands. The Amtoudi Oasis, a remote area in southern Morocco, in the northern Sahara attractive for tourism and with evidence of groundwater degradation, was chosen to show the model operation. Governing system variables were identified and put into action through System Dynamics (SD) modeling causal diagrams to program basic formulations into a model having two modules coupled by the nexus ‘pumping’: (1) the hydrological module represents the net groundwater balance (G) dynamics; and (2) the economic module reproduces the variation in the consumers of water, both the population and tourists. The model was operated under similar influx of tourists and different scenarios of water availability, such as the wet 2009–2010 and the average 2010–2011 hydrological years. The rise in international tourism is identified as the main driving force reducing emigration and introducing new social habits in the population, in particular concerning water consumption. Urban water allotment (PU) was doubled for less than a 100-inhabitant net increase in recent decades. The water allocation for agriculture (PI), the largest consumer of water, had remained constant for decades. Despite that the 2-year monitoring period is not long enough to draw long-term conclusions, groundwater imbalance was reflected by net aquifer recharge (R) less than PI + PU (G < 0) in the average year 2010–2011, with net lateral inflow from adjacent Cambrian formations being the largest recharge component. R is expected to be much less than PI + PU in recurrent dry spells. Some low-technology actions are tentatively proposed to mitigate groundwater degradation, such as: wastewater capture, treatment, and reuse for irrigation; storm-water harvesting for irrigation; and active maintenance of the irrigation system to improve its efficiency.
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[Introduction.] Over the last two years, not only inside but also outside the framework of the EU treaties, far reaching measures have been taken at the highest political level in order to address the financial and economic crisis in Europe and in particular the sovereign debt crisis in the Euro area. This has triggered debates forecasting the “renationalisation of European politics.” Herman Van Rompuy, the President of the European Council, countered the prediction that Europe is doomed because of such a renationalisation: “If national politics have a prominent place in our Union, why would this not strengthen it?” He took the view that not a renationalisation of European politics was at stake, but an Europeanization of national politics emphasising that post war Europe was never developed in contradiction with nation states.1 Indeed, the European project is based on a mobilisation of bundled, national forces which are of vital importance to a democratically structured and robust Union that is capable of acting in a globalised world. To that end, the Treaty of Lisbon created a legal basis. The new legal framework redefines the balance between the Union institutions and confirms the central role of the Community method in the EU legislative and judiciary process. This contribution critically discusses the development of the EU's institutional balance after the entry into force of the Treaty of Lisbon, with a particular emphasis on the use of the Community Method and the current interplay between national constitutional courts and the Court of Justice. This interplay has to date been characterised by suspicion and mistrust, rather than by a genuine dialogue between the pertinent judicial actors.
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A new CEPS Task Force Report has identified possible pathways for achieving the EU’s ambitious climate change targets. It concludes that a GHG emissions reduction in line with EU climate change policy is possible, but it requires immediate action. This report argues that most of the reductions required of the transport sector in the EU could come from more energy-efficient vehicles, combined with the gradual introduction of low-carbon fuels and new engine technologies. The key policy for reducing GHG emissions in road transport is the steady tightening of emissions standards in line with technological progress. The report also identifies strategies for the transport system to become more energy and/or carbon efficient, arguing that leverage can be further enhanced by local and city governments’ incentives for efficient and low-carbon vehicles in line with local circumstances and choices. The Task Force on Low Carbon Transport brought together a diverse set of stakeholders from the car and oil industries, business associations, international organisations, member states, academic experts and NGOs. This authoritative report is the result of that unique collaboration.
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The SME access-to-finance problem is not universal in the European Union and there are reasons for the fall in credit aggregates and higher SME lending rates in southern Europe. Possible market failures, high unemployment and externalities justify making greater and easier access to finance for SMEs a top priority. Previous European initiatives were able to support only a tiny fraction of Europe’s SMEs; merely stepping-up these programmes is unlikely to result in a breakthrough. Without repairing bank balance sheets and resuming economic growth, initiatives to help SMEs get access to finance will have limited success. The European Central Bank can foster bank recapitalisation by performing in the toughest possible way the asset quality review before it takes over the single supervisory role. Of the possible initiatives for fostering SME access to finance, a properly designed scheme for targeted central bank lending seems to be the best complement to the banking clean-up, but other options, such as increased European Investment Bank lending and the promotion of securitisation of SME loans, should also be explored.
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Estimates of the recapitalisation needs of the euro-area banking system vary between €50 and €600 billion. The range shows the considerable uncertainty about the quality of banks’ balance sheets and about the parameters of the forthcoming European Central Bank stress tests, including the treatment of sovereign debt and systemic risk. Uncertainty also prevails about the rules and discretion that will applyto bank recapitalisation, bank restructuring and bank resolution in 2014 and beyond. The ECB should communicate the relevant parameters of its exercise early and in detail to give time to the private sector to find solutions. The ECB should establish itself as a tough supervisor and force non-viable banks into restructuring. This could lead to short-term financial volatility, but it should be weighed against the cost of a durably weak banking system and the credibility risk to the ECB. The ECB may need to provide large amounts of liquidity to the financial system. Governments should support the ECB, accept cross-border bank mergers and substantial creditor involvement under clear bail-in rules and should be prepared to recapitalise banks. Governments should agree on the eventual creation of a single resolution mechanism with efficient and fast decision-making procedures, and which can exercise discretion where necessary. A resolution fund, even when fully built-up, needs to have a common fiscal backstop to be credible.
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The Spitzenkandidaten experiment has been at the centre of a heated debate for several months now, prompting much speculation as to the changes it will bring to the balance of power between the EU institutions. But the real coup d’état has been directed against the old process of appointing the European Commission President behind closed doors. Although the new procedure entails “a number of political, institutional and ‘thus’ constitutional ambiguities”, according to the authors of this commentary, it has rendered that process more transparent, if not more democratic – and will almost certainly endure to the next European elections in 2019 and beyond. As a result, they conclude that the new procedure is likely to trigger important changes in Europe’s political parties and elections.
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This Task Force report combines the most recent data from Eurostat with national sources to highlight the most significant labour mobility trends within the EU. Overall, the recent recession has not induced previously immobile workers to become more mobile, at least not in the larger member states. Mobility flows have moved away from crisis countries in response to the economic downturn but the desired increase in south-north mobility has not been observed so far. This leads the authors to conclude that successfully fostering mobility within EU15 countries requires tremendous effort. It is important that workers who are willing and able to move are not discouraged from doing so by unnecessary barriers to mobility. Improving the workings of the EURES system and its online job-matching platform; better cooperation of national employment agencies; streamlining the recognition of qualifications; and supporting language training within the EU are important contributions to labour mobility. The authors conclude that the EU is right to defend the free movement of workers. National governments should keep in mind that their ability to tap into an attractive foreign labour supply also hinges upon the perception of how mobile workers are treated in destination countries. If the political imperative requires regulations to be changed, such as the one guiding the coordination of social security, it is essential that no new mobility barriers are put in place.
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A key element of Russia’s policy towards the new government of Ukraine concerns demands for a constitutional reform that would transform the country from a unitary into a federal state in a way that would considerably privilege the eastern and southern regions. Such a change to Ukraine’s administrative system would enable Moscow to put pressure on Ukraine’s central government via the regions. In order to achieve its objectives, Russia has been pressuring Kyiv to establish a constitutional assembly in a form that would guarantee the endorsement of solutions dictated by Russia. In other words, Russia has been demanding, in what is practically an ultimatum, that Ukraine give up one of the fundamental sovereign rights of a state, the right to freely determine its system of government. Transforming Ukraine into a federal state is an unacceptable idea, primarily because the intention behind Russia’s demands is to undermine Ukraine’s sovereignty, both through the content of the proposed changes and the way in which they are to be implemented. However, keeping in place the current, centralist model of state governance is not a feasible alternative. Ukraine will have to grant its regions broad self-governance powers, including the power to hold local referendums, and to transfer a considerable portion of the prerogatives currently held by the state to the local self-governments, along with adequate financial resources. That is because decentralisation along these lines is the only way forward towards a modern democracy in Ukraine. Russia’s policy has forced Kyiv to undertake legislative work on constitutional reform as a matter of urgency, rather than waiting until a new parliament is elected in which the new, post-Maidan balance of political power will be reflected, as political logic would require. The first draft of the constitutional amendments (of which no details are known at this stage) is to be presented in mid-May, and is expected to come into force in early autumn. However, whether these plans can be put into practice depends on further developments in the eastern part of Ukraine, because (among other reasons) if a state of emergency is introduced, the constitutional amendment process will have to be suspended.
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2002 elections: On 31 March 2002, parliamentary elections were held in Ukraine. As expected, they were a major success for the centrist-rightist coalition focused around former Prime Minister Viktor Yuschenko. The communists emerged significantly weaker from the vote, and the "party of power" achieved a poor result. Yet, due to the mixed electoral law (half of the deputies were elected in single-mandate districts), the latter block, firmly supported by President Leonid Kuchma, resulted as the main force in Parliament. The results of particular parties and blocks were as follows: Viktor Yuschenko's Block received 23.57% of votes and 112 seats, the Communist Party of Ukraine - 19.98% of votes and 66 seats, the "For One Ukraine" block - 11.77% of votes and 101 seats, Yulia Tymoshenko's Block - 7.26% of votes and 22 seats, the Socialist Party of Ukraine - 6.87% of votes and 22 seats, and the Social Democratic Party of Ukraine (united) - 6.27% of votes and 24 seats. This shows how the mixed electoral regulations favour "For One Ukraine" and act against Yuschenko's block. One should note, however, that the latter gained the support of less than one quarter of voters. After the election: The dominant force in Ukraine's Verkhovna Rada, elected in March 2002, are the deputies of "One Ukraine", a fraction of the pro-presidential centre. "One Ukraine" has refused to admit any of the opposition's representatives (either from the right or left wings) into the parliament's presidium, but has accepted opposition-appointed heads of many parliamentary commissions. Viktor Yuschenko's "Our Ukraine", which has been the largest parliamentary fraction since June, attempted to proclaim itself the centre of the parliamentary majority, but its policy was awkward and inconsistent, and the main success of this club was that it didn't break up. Viktor Yuschenko's moves have been particularly incoherent and they undermined the image of Yuschenko as Ukraine's future leader, created throughout the course of the electoral campaign. In autumn, the main oligarchic groups and their representative fractions ("One Ukraine", which proved to be a useless instrument, was dissolved in June), reached a compromise with the president. It was agreed that the new prime minister should be a Donetsk clan representative (Viktor Yanukovych), and that the Dnipropetrovsk clan should appoint the president of the National Bank of Ukraine (this position went to Serhij Tihipko). The Kyiv clan obtained the President's Administration (Viktor Medvedchuk was appointed in spring) and a considerable number of parliamentary commissions. The president's interests in the government are to be protected by Mykola Azarov, former Head of the State Tax Administration. This compromise "package" was designed to secure the shares of the main oligarchic clans in the power and the president's strong position as mediator.