124 resultados para Nikolas Ormaetxea


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The Escherichia coli DNA repair enzyme MutY plays an important role in the prevention of DNA mutations by removing misincorporated adenine residues from 7,8-dihydro-8-oxo-2′-deoxyguanosine:2′-deoxyadenosine (OG:A) mispairs. The N-terminal domain of MutY (Stop 225, Met1–Lys225) has a sequence and structure that is characteristic of a superfamily of base excision repair glycosylases; however, MutY and its homologs contain a unique C-terminal domain. Previous studies have shown that the C-terminal domain confers specificity for OG:A substrates over G:A substrates and exhibits homology to the d(OG)TPase MutT, suggesting a role in OG recognition. In order to provide additional information on the importance of the C-terminal domain in damage recognition, we have investigated the kinetic properties of a form lacking this domain (Stop 225) under multiple- and single-turnover conditions. In addition, the interaction of Stop 225 with a series of non-cleavable substrate and product analogs was evaluated using gel retardation assays and footprinting experiments. Under multiple-turnover conditions Stop 225 exhibits biphasic kinetic behavior with both OG:A and G:A substrates, likely due to rate-limiting DNA product release. However, the rate of turnover of Stop 225 was increased 2-fold with OG:A substrates compared to the wild-type enzyme. In contrast, the intrinsic rate for adenine removal by Stop 225 from both G:A and OG:A substrates is significantly reduced (10- to 25-fold) compared to the wild-type. The affinity of Stop 225 for substrate analogs was dramatically reduced, as was the ability to discriminate between substrate analogs paired with OG over G. Interestingly, similar hydroxyl radical and DMS footprinting patterns are observed for Stop 225 and wild-type MutY bound to DNA duplexes containing OG opposite an abasic site mimic or a non-hydrogen bonding A analog, suggesting that similar regions of the DNA are contacted by both enzyme forms. Importantly, Stop 225 has a reduced ability to prevent DNA mutations in vivo. This implies that the reduced adenine glycosylase activity translates to a reduced capacity of Stop 225 to prevent DNA mutations in vivo.

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This paper reviews the current EU policy framework in view of its impact on hydrogen and fuel cell development. It screens EU energy policies, EU regulatory policies and EU spending policies. Key questions addressed are as follows: To what extent is the current policy framework conducive to hydrogen and fuel cell development? What barriers and inconsistencies can be identified? How can policies potentially promote hydrogen and fuel cells in Europe, taking into account the complex evolution of such a disruptive technology? How should the EU policy framework be reformed in view of a strengthened and more coherent approach? The paper concludes that the current EU policy framework does not hinder hydrogen development. Yet it does not constitute a strong push factor either. EU energy policies have the strongest impact on hydrogen and fuel cell development even though their potential is still underexploited. Regulatory policies have a weak but positive impact on hydrogen. EU spending policies show some inconsistencies. However, the large scale market development of hydrogen and fuel cells will require a new policy approach which comprises technology specific support as well as a supportive policy framework with a special regional dimension.

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This study takes on the issue of political and socio-economic conditions for the hydrogen economy as part of a future low carbon society in Europe. It is subdivided into two parts. A first part reviews the current EU policy framework in view of its impact on hydrogen and fuel cell development. In the second part an analysis of the regional dynamics and possible hydrogen and fuel cell clusters is carried out. The current EU policy framework does not hinder hydrogen development. Yet it does not constitute a strong push factor either. EU energy policies have the strongest impact on hydrogen and fuel cell development even though their potential is still underexploited. Regulatory policies have a weak but positive impact on hydrogen. EU spending policies show some inconsistencies. Regions with a high activity level in HFC also are generally innovative regions. Moreover, the article points out certain industrial clusters that favours some regions' conditions for taking part in the HFC development. However, existing hydrogen infrastructure seems to play a minor role for region's engagement. An overall well-functioning regional innovation system is important in the formative phase of an HFC innovation system, but that further research is needed before qualified policy implications can be drawn. Looking ahead the current policy framework at EU level does not set clear long term signals and lacks incentives that are strong enough to facilitate high investment in and deployment of sustainable energy technologies. The likely overall effect thus seems to be too weak to enable the EU hydrogen and fuel cell deployment strategy. According to our analysis an enhanced EU policy framework pushing for sustainability in general and the development of hydrogen and fuel cells in particular requires the following: 1) A strong EU energy policy with credible long term targets; 2) better coordination of EU policies: Europe needs a common understanding of key taxation concepts (green taxation, internalisation of externalities) and a common approach for the market introduction of new energy technologies; 3) an EU cluster policy as an attempt to better coordinate and support of European regions in their efforts to further develop HFC and to set up the respective infrastructure.

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Compressional wave velocities and densities were measured for 6 basalt samples from ODP Hole 801B and 16 samples from ODP Hole 801C, a site that represents the first drilling of Jurassic-age crustal rocks in the Pacific basin. Incremental measurements, taken to a total pressure of 200 MPa, show a systematic decrease in velocity with increasing porosity and a related increase with increasing wet-bulk density. A comparison of the plot of porosity vs. compressional wave velocity with the theoretical equation from Wyllie et al. (1958) suggests this equation is inappropriate for oceanic basalts because of mineral alteration in high porosity samples. Also of interest is the dramatic change in velocity across a hydrothermal boundary. Basalts below this hydrothermal layer have a mean velocity of 6.05 km/s at 60 MPa while those above show a mean velocity of 4.55 km/s at 60 MPa. The low velocity values of the basalts above the hydrothermal deposit may be attributed to the higher porosity and composition observed in these rocks; the higher porosity is possibly the result of increased exposure to circulating seawater.

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Gavotte pastorale / A. Arensky -- Golden wedding minuet / G. Karganoff -- Arabesque / G. Karganoff -- Berceuse / Alex Ilynsky -- Fantastic tale / H. Pachulski -- Slumber song / L. Arkadieff -- Album leaf, in C / Alexander Kopylow -- Romance in A[flat] / Nikolas Rimsky-Korsakoff -- Arabesque / B. Wrangell -- Canzonetta / Caesar Cui -- Nocturne / Ignace Krzyzanowski -- Berceuse / G. Karganoff -- Prelude / A. Kopylow -- The Cuckoo / A. Arensky -- Elegie / Sergei Yóuferoff -- Valse capricieuse / Boleslaus Grodzki -- Intermezzo / G. Karganoff -- Berceuse / S. Barmotine -- The Music box / Anatole Liadow -- Novellette / N. Rimsky-Korsakow -- Tarentelle / Gʹenari Karganoff -- By the sea / A. Arensky.

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Since the early 1980s, Australian governments have embraced neoliberal policies as a means of improving the nation’s global economic competitiveness. The impacts of such policies in regional areas have been quite profound, leading to socio-economic polarisation, population loss, and the growth of anti-globalisation sentiments. In this paper, we examine the process of regional restructuring that arises from this trajectory in Australia, and examine current policy responses to change under the neoliberal regime. We argue that while many such responses are individualistic, and based upon policies of personal responsibility, self-advancement and entrepreneurship, others are imbued with the language of community, social capital and collective action. The existence of individualism and community within the same policy agenda may appear contradictory, yet it is suggested that neoliberalism brings together these two opposing discourses through a process of what Nikolas Rose calls ‘governing through community’. We explore how neoliberalism underpins community approaches to regional development in Australia, arguing that such strategies do little to counter the negative forces of globalisation in non-metropolitan parts of the country.

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Reaction of 6-ethoxylepidine (6-ethoxy-4-methylquinoline) with strong base and electrophiles leads to new derivatives; as possible optoquine analogues

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Contents: 1 Introduction: European integration as an elite project, Heinrich Best, György Lengyel, and Luca Verzichelli; 2 Europe à la carte? European citizenship and its dimensions from the perspective of national elites, Maurizio Cotta and Federico Russo; 3 Ready to run Europe? Perspectives of a supranational career among EU national elites, Nikolas Hubé and Luca Verzichelli; 4 National elites’ preferences on the Europeanization of policy making, José Real-Dato, Borbála Göncz, and György Lengyel; 5 The other side of European identity: elite perceptions of threats to a cohesive Europe, Irmina Matonyté and Vaidas Morkevicius; 6 Elites’ views on European institutions: national experiences sifted through ideological orientations, Daniel Gaxie and Nicolas Hubé; 7 Patterns of regional diversity in political elites’ attitudes, Mladen Lazic, Miguel Jerez-Mir, Vladimir Vuletic, and Rafael Vázquez-García; 8 The elites–masses gap in European integration, Wolfgang C. Müller, Marcelo Jenny, and Alejandro Ecker; 9 Party elites and the domestic discourse on the EU, Nicolo Conti; 10 Elite foundations of European integration: a causal analysis, Heinrich Best; 11 Elites of Europe and the Europe of elites: a conclusion, Heinrich Best; 12 Appendix. Surveying elites: information on the study design and field report of the IntUne elite survey, György Lengyel and Stefan Jahr.

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Compressional- and shear-wave velocity logs (Vp and Vs, respectively) that were run to a sub-basement depth of 1013 m (1287.5 m sub-bottom) in Hole 504B suggest the presence of Layer 2A and document the presence of layers 2B and 2C on the Costa Rica Rift. Layer 2A extends from the mudline to 225 m sub-basement and is characterized by compressional-wave velocities of 4.0 km/s or less. Layer 2B extends from 225 to 900 m and may be divided into two intervals: an upper level from 225 to 600 m in which Vp decreases slowly from 5.0 to 4.8 km/s and a lower level from 600 to about 900 m in which Vp increases slowly to 6.0 km/s. In Layer 2C, which was logged for about 100 m to a depth of 1 km, Vp and Vs appear to be constant at 6.0 and 3.2 km/s, respectively. This velocity structure is consistent with, but more detailed than the structure determined by the oblique seismic experiment in the same hole. Since laboratory measurements of the compressional- and shear-wave velocity of samples from Hole 504B at Pconfining = Pdifferential average 6.0 and 3.2 km/s respectively, and show only slight increases with depth, we conclude that the velocity structure of Layer 2 is controlled almost entirely by variations in porosity and that the crack porosity of Layer 2C approaches zero. A comparison between the compressional-wave velocities determined by logging and the formation porosities calculated from the results of the large-scale resistivity experiment using Archie's Law suggest that the velocity- porosity relation derived by Hyndman et al. (1984) for laboratory samples serves as an upper bound for Vp, and the noninteractive relation derived by Toksöz et al. (1976) for cracks with an aspect ratio a = 1/32 serves as a lower bound.