200 resultados para 2117
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Edit16,
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Part 21 (Index) issued with separate paging (iii, 268 p.).
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FVT of pyrroledione 10 affords the NH-imidoylketene 11, which is characterized by its matrix isolation IR spectrum ( 2117 cm 1). On warming above 170 K, 11 dimerizes to the oxazinone 13, the X-ray crystal structure of which is reported. Imidoylketene 11 also undergoes a (reversible) 1,3-phenyl shift to afford the detectable alpha-oxoketenimine 16 (2062 cm(-1)) which at FVT temperatures above 400degreesC, isomerizes to 2-cyano-2-phenylacetophenone 18 (optimally at 700degreesC). Moreover, imidoylketene 11 can cyclize to azetinone 19, detectable at FVT temperatures up to 570degreesC, which undergoes cycloreversion to diphenylacetylene 20 and isocyanic acid (HNCO) 21. Energy profiles calculated at the B3LYP/6-31G** level for the unsubstituted imidoylketene, the diphenylimidoylketene 11 and the N-tert-butylimidoylketene are also reported.
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This paper analyses the efficiency of Malaysian commercial banks between 1996 and 2002 and finds that while the East Asian financial crisis caused a short-term increase in efficiency in 1998 primarily due to cost-cutting, increases in non-performing loans after the crisis caused a more sustained decline in bank efficiency. It is also found that mergers, fully Islamic banks, and conventional banks operating Islamic banking windows are all associated with lower efficiency. The paper estimates suggest mild decreasing returns to scale, and an average productivity change of 2.37% that is primarily attributable to technical change, which has nonetheless declined over time. Finally, while Islamic banks have been moderately successful in developing new products and technologies, the results suggest that the potential for Islamic banks to overcome their relative inefficiency is limited.
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A series of novel block copolymers, processable from single organic solvents and subsequently rendered amphiphilic by thermolysis, have been synthesized using Grignard metathesis (GRIM) and reversible addition-fragmentation chain transfer (RAFT) polymerizations and azide-alkyne click chemistry. This chemistry is simple and allows the fabrication of well-defined block copolymers with controllable block lengths. The block copolymers, designed for use as interfacial adhesive layers in organic photovoltaics to enhance contact between the photoactive and hole transport layers, comprise printable poly(3-hexylthiophene)-block-poly(neopentyl p-styrenesulfonate), P3HT-b-PNSS. Subsequently, they are converted to P3HT-b-poly(p-styrenesulfonate), P3HT-b-PSS, following deposition and thermal treatment at 150 °C. Grazing incidence small- and wide-angle X-ray scattering (GISAXS/GIWAXS) revealed that thin films of the amphiphilic block copolymers comprise lamellar nanodomains of P3HT crystallites that can be pushed further apart by increasing the PSS block lengths. The approach of using a thermally modifiable block allows deposition of this copolymer from a single organic solvent and subsequent conversion to an amphiphilic layer by nonchemical means, particularly attractive to large scale roll-to-roll industrial printing processes.
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Misophonia is characterized by a negative reaction to a sound with a specific pattern and meaning to a given individual. In this paper, we review the clinical features of this relatively common yet underinvestigated condition, with focus on co-occurring neurodevelopmental disorders. Currently available data on the putative pathophysiology of the condition can inform our understanding and guide the diagnostic process and treatment approach. Tinnitus retraining therapy and cognitive behavior therapy have been proposed as the most effective treatment strategies for reducing symptoms; however, current treatment algorithms should be validated in large population studies. At the present stage, competing paradigms see misophonia as a physiological state potentially inducible in any subject, an idiopathic condition (which can present with comorbid psychiatric disorders), or a symptomatic manifestation of an underlying psychiatric disorder. Agreement on the use of standardized diagnostic criteria would be an important step forward in terms of both clinical practice and scientific inquiry. Areas for future research include phenomenology, epidemiology, modulating factors, neurophysiological underpinnings, and treatment trials.
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Petar Radoev Popivanov was born on April 6, 1946 in Sofia. Traces of this branch of Popivanov’s are found in the late 1700’s in Lyaskovets, a small town near Veliko Tarnovo, the old capital of the second Bulgarian kingdom. In the family tree one finds in the last 200 years or so lawyers, men of learning, men of politics, military officers, physicians, priests. In particular, his father Radoy Popivanov (1913-2010) was a well known Bulgarian scientist in Biology and Immunogenetics and a Full Member of the Bulgarian Academy of Sciences (BAS).
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Az írás a globális értékláncok élén álló autóipari cégek világgazdasági válságra adott reakcióit foglalja össze. Megállapítja, hogy a válságnak messze nincs vége: az iparág globális átrendeződése folytatódik. A globális értékláncokba sikeresen betagozódott közép-európai autóipari klaszter ezeknek a folyamatoknak mindmáig nyertese volt. Számolni kell azonban azzal, hogy továbbra is sok a technológiai és a piaci bizonytalanság: az új szereplők belépése, új üzleti modellek elterjedése hosszabb távon felboríthatja a jelenlegi status quo-t, és veszélyeztetheti a hagyományos autóipari befektetőiket munkabér-alapú versenyképességgel megtartani próbáló közép- és kelet-európai országok pozícióit. Az autóipari működő tőkét fogadó közép-kelet-európai országok számára hosszabb távon veszélyt jelenthet az autóipari üzleti modellek átalakulása, a gyártás teljes kiszervezése komplex gyártási szolgáltatást vállaló cégekhez, mivel ez esetben az értéklánc vezető vállalatai bezárhatják a régióban működő gyártóbázisaikat. Az értékláncok élén álló globális cégek „menekülés a minőségbe” stratégiája helyi szinten is követhető, követendő, a működő tőkét fogadó országok versenyképessége kizárólag a helyi leányvállalatok állandó „feljebb lépésével” tartható fenn. ______ This paper summarizes lead firms’ reactions to crisis in global automotive value chains. The paper advances five theses. Author argues that crisis is not over yet, the global restructuring of the industry continues. Actors in the CEE automotive cluster have successfully become integrated into global value chains and have thereby been the winners of past restructuring processes. Nevertheless, technological and market uncertainties prevail: entry of new economic actors and the diffusion of new business models may, in the long run, disrupt the current status quo and jeopardise the world economic position of CEE countries that have been relying solely on their labour cost advantages to sustain direct investment inflows in their automotive industries. In the long run the automotive industries of Central and Eastern European (CEE) economies may become threatened by the transformation of the prevailing automotive business model, the outsourcing of manufacturing and related support activities to complex manufacturing services providers, which could lead to the closure of lead firms’ manufacturing facilities in CEE. Lead firms’ increased focus on high quality high value adding activities strategy can and should be followed by local subsidiaries through a continuous strive for upgrading.
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Numa sociedade hodierna caraterizada por uma crescente e, aparentemente, irreversível globalização assistimos a um fluxo migratório de trabalhadores que escolhem países que não o seu de origem para desenvolver a sua atividade profissional. Este fluxo vem promover o aumento da diversidade de culturas nos países de acolhimento, diversidade que se alarga a um contexto religioso. Pese embora a laicidade formal do Estado Português, bem como da generalidade dos Estados europeus, a legislação laboral interna não consegue, por si só, estabelecer uma proteção adequada a todas as religiões, nomeadamente as minoritárias, o que nos levou a abordar esta questão analisando a proteção dada pela Convenção Europeia dos Direitos do Homem, como instrumento solene de proclamação de Direitos Humanos, e o subsequente tratamento jurisprudencial do Tribunal Europeu dos Direitos do Homem no que tange à liberdade religiosa dos trabalhadores. Através da análise dos diversos casos levados até ao Tribunal de Estrasburgo, cumpre, por um lado, aferir da eficácia da legislação existente e, por outro, e com o respeito da mesma, perceber até que ponto pode a liberdade religiosa de um trabalhador ceder aquando da celebração de um contrato de trabalho ou até onde deve um empregador ajustar a sua organização em respeito à liberdade religiosa dos seus trabalhadores nas suas diversas manifestações. Nesse sentido, analisaremos alguns casos de âmbito juslaboral em que as restrições impostas aos trabalhadores consubstanciam eventuais violações da sua liberdade religiosa nas mais diversas manifestações, nomeadamente, quanto a questões de índole religiosa atinentes a vestuário, horários ou alimentação entre outras.
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Calcium signaling has long been associated with key events of immunity, including chemotaxis, phagocytosis, and activation. However, imaging and manipulation of calcium flux in motile immune cells in live animals remain challenging. Using light-sheet microscopy for in vivo calcium imaging in zebrafish, we observe characteristic patterns of calcium flux triggered by distinct events, including phagocytosis of pathogenic bacteria and migration of neutrophils toward inflammatory stimuli. In contrast to findings from ex vivo studies, we observe enriched calcium influx at the leading edge of migrating neutrophils. To directly manipulate calcium dynamics in vivo, we have developed transgenic lines with cell-specific expression of the mammalian TRPV1 channel, enabling ligand-gated, reversible, and spatiotemporal control of calcium influx. We find that controlled calcium influx can function to help define the neutrophil's leading edge. Cell-specific TRPV1 expression may have broad utility for precise control of calcium dynamics in other immune cell types and organisms.
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The mid-Holocene (6000 calibrated years before present) is a key period in palaeoclimatology because incoming summer insolation was lower than during the late Holocene in the Southern Hemisphere, whereas the opposite happened in the Northern Hemisphere. However, the effects of the decreased austral summer insolation over South American climate have been poorly discussed by palaeodata syntheses. In addition, only a few of the regional studies have characterised the mid-Holocene climate in South America through a multiproxy approach. Here, we present a multiproxy compilation of mid-Holocene palaeoclimate data for eastern South America. We compiled 120 palaeoclimatological datasets, which were published in 84 different papers. The palaeodata analysed here suggest a water deficit scenario in the majority of eastern South America during the mid-Holocene if compared to the late Holocene, with the exception of northeastern Brazil. Low mid-Holocene austral summer insolation caused a reduced land-sea temperature contrast and hence a weakened South American monsoon system circulation. This scenario is represented by a decrease in precipitation over the South Atlantic Convergence Zone area, saltier conditions along the South American continental margin, and lower lake levels.
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The Oporto Airport located in the northern region in Porto city is crucial because is the only one located in the northern region. This airport had an increasing in number of passengers, sales revenue and accumulated investment during the last two decades, principally after the introduction and the operation of the Low Cost Companies since 2004 to the present. In order to determine if the last changes had an impact in the competitiveness of this airport, the main aims is to analise the evolution of values of the technical efficiency and equate the results before and after the introduction of the LCCs in this airport. The methodology uses the Data Envelopment Analysis. Results show that the Oporto Airport efficiency increases highly after the introduction of LCCs since 2004. The main conclusions suggest the importance of the introduction of LCCs in the increasing efficiency of the Oporto Airport and the potential relation with tourism development in this region, but more strong studies are needed.
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Colloque tenu en Sorbonne les 17-19 janvier 2008
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The aim of present work was to investigate the phenolic and volatile composition of cherry, acacia, and oak (from different species) wood chips. By the use of HPLC-DAD 18 different phenolic compounds were detected and quantified while for volatile composition, 33 different compounds were detected by GC-MS. In general, wood samples from oak species showed the higher number of phenolic compounds detected, while cherry wood samples showed the lowest levels. In addition, some individual phenolic compounds were detected, specifically in some wood samples, such as robinetin in acacia woods and naringenin in cherry wood. For volatile composition, cherry wood chips samples showed the lowest volatile composition followed by increasing order by acacia, French, Portuguese and American wood chip samples. Oak wood chip samples from American species showed the highest volatile content, as a result of high levels of several specific compounds (furfural, 5-methyfurfural, β-methyl-γ-octalactones, guaiacol, vanillin and siringaldehyde).