926 resultados para truncation lag
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The threats posed by climate change are placing governments under increasing pressure to meet electricity demand from low carbon sources. Wind energy has been has been identified as one of the main technologies to help in meeting these demands. The public in general favour wind energy yet proposed targets for generation capacity lag behind proposed goals. The N IM B Y phenomenon has been suggested as one of the reasons why we are behind our wind generation capacity targets. It is a common mistake to take general support for granted and expect the public to support developments when confronted with them in their local area. In many cases it is not unheard of that governing bodies whether social, political, regulatory, environmental, or cultural can overrule general public support and halt developments. Motives to halt developments will vary depending on the institutional body involved. The problem with the term N IM B Y is that it is too basic a term to describe the broad spectrum of complex motives that various institutions including the public may have against a development. This research focuses on a case study where the developer had major problems with the local county council and its wind energy policies when he was erecting a wind turbine despite having gained planning permission. A survey questionnaire was also used as part o f the research to seek the perception a rural community had on wind energy. The research findings and results are discussed with respect to the literature review highlighting a general public support for wind energy and the influence institutional bodies have over the progress of developments.
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In der vorliegenden Masterarbeit wurde das Protein nuclear factor 110 (NF110) in vitro rückgefaltet, chromatographisch gereinigt, durch den Zusatz von L-Arginin stabilisiert und seine Affinität gegenüber RNAs untersucht. Das Ausgangsmaterial wurde mittels Dialyse zurückgefaltet und über drei aufeinander folgende Chromatographieschritte gereinigt: mittels Kationenaustauschchromatographie (capture) zur Entfernung von Fremdproteinen, Größenausschlusschromatographie (intermediate) zur Trennung des monomeren Proteins von höher-oligomeren Spezies und der Affinitätschromatographie (polishing). Diese Proteinlösung wurde unter Zusatz von 500 mM L-Arginin gelagert um eine Proteinaggregation zu unterbinden. Durch Streulichtmessungen und eine analytische Ultrazentrifugation konnte erfolgreich nachgewiesen werden, dass NF110 erst in Puffern mit mindestens 200 mM L-Arginin stabil vorliegt. Im Rahmen der vorliegenden Arbeit konnte erfolgreich bestimmt werden, dass NF110 zwischen doppelsträngiger RNA und DNA diskriminiert, während es gegenüber einzel- bzw. doppelsträngiger RNA ähnlich affin ist. Dies stellt einen großen Unterschied zu NF90 dar. Diese C-terminal verkürzte Variante interagiert mit einzelsträngiger RNA in sehr geringerem Umfang als mit doppelsträngiger RNA (Schmidt, 2015). Daher kann vermutet werden, dass der C-Terminus, insbesondere das dort befindliche GQSY-Motiv, für die Spezifität gegenüber den RNAs verantwortlich ist. Ein weiterer Fokus der Arbeit lag auf dem Einfluss von L-Arginin bei der RNA-Bindung. Mit Hilfe einer linearen freien Enthalpiebeziehung (LFER) konnte so eine Dissoziationskonstante für nicht aggregierendes NF110 ohne L-Arginin ermittelt werden. Außerdem wurde ersichtlich, dass dieser Stabilisator zwar die Aggregation hemmt, aber nur marginal die RNA-Bindung des Proteins beeinflusst
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This article examines the European integration process from a sociological perspective, where the main focus is the examination of the social consequences of the integration process. The European Union has advanced significantly in the economic, social, and political integration processes. This has resulted in a rapid Europeanization of behavior. There has hardly been any progress, however, toward the development of European social groups. This article examines the causes of this lag and concludes that it is highly unlikely that in the middle run there be significant progress toward the Europeanization of society.
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Peripheral nerve injury is a serious problem affecting significantly patients' life. Autografts are the "gold standard" used to repair the injury gap, however, only 50% of patients fully recover from the trauma. Artificial conduits are a valid alternative to repairing peripheral nerve. They aim at confining the nerve environment throughout the regeneration process, and providing guidance to axon outgrowth. Biocompatible materials have been carefully designed to reduce inflammation and scar tissue formation, but modifications of the inner lumen are still required in order to optimise the scaffolds. Biomicking the native neural tissue with extracellular matrix fillers or coatings showed great promises in repairing longer gaps and extending cell survival. In addition, extracellular matrix molecules provide a platform to further bind growth factors that can be released in the system over time. Alternatively, conduit fillers can be used for cell transplantation at the injury site, reducing the lag time required for endogenous Schwann cells to proliferate and take part in the regeneration process. This review provides an overview on the importance of extracellular matrix molecules in peripheral nerve repair.
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Road safety has become an increasing concern in developed countries due to the significant amount of mortal victims and the economic losses derived. Only in 2005 these losses rose to 200.000 million euros, a significant amount - approximately the 2% of its GDP- that easily justifies any public intervention. One tool used by governments to face this challenge is the enactment of stricter policies and regulations. Since drunk driving is one of the most important concerns of public authorities on this field, several European countries decided to lower their illegal Blood Alcohol Content levels to 0.5 mg/ml during the last decade. This study evaluates for the first time the effectiveness of this transition using European panel-based data (CARE) for the period 1991-2003 using the Differences-in-Differences method in a fixed effects estimation that allows for any pattern of correlation (Cluster-Robust). My results show the existence of positive impacts on certain groups of road users and for the whole population when the policy is accompanied by some enforcement interventions. Moreover, a time lag of more than two years is found in that effectiveness. Finally, I also assert the importance of controlling for serial correlation in the evaluation of this kind of policies.
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The effect of mortality reductions on fertility is one of the main mechanisms stressed by the recent growth literature in order to explain demographic transitions. We analyze the empirical relevance of this mechanism based on the experience of all countries since 1960. We distinguish between the effects on gross and net fertility, take into account the dynamic nature of the relationship and control for alternative explanatory factors and for endogeneity. Our results show that mortality plays a large role in fertility reductions, that the change in fertility behavior comes with a lag of about 10 years and that both net and gross fertility are affected. We find comparatively little support for explanations of the demographic transition based on economic development or technological change.
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Background: There is little information regarding the impact of diet on disease incidence and mortality in Switzerland. We assessed ecologic correlations between food availability and disease.Methods: In this ecologic study for the period 1970-2009, food availability was measured using the food balance sheets of the Food and Agriculture Organization of the United Nations. Standardized mortality rates (SMRs) were obtained from the Swiss Federal Office of Statistics. Cancer incidence data were obtained from the World Health Organization Health For All database and the Vaud Cancer Registry. Associations between food availability and mortality/incidence were assessed at lags 0, 5, 10, and 15 years by multivariate regression adjusted for total caloric intake.Results: Alcoholic beverages and fruit availability were positively associated, and fish availability was inversely associated, with SMRs for cardiovascular diseases. Animal products, meat, and animal fats were positively associated with the SMR for ischemic heart disease only. For cancer, the results of analysis using SMRs and incidence rates were contradictory. Alcoholic beverages and fruits were positively associated with SMRs for all cancer but inversely associated with all-cancer incidence rates. Similar findings were obtained for all other foods except vegetables, which were weakly inversely associated with SMRs and incidence rates. Use of a 15-year lag reversed the associations with animal and vegetal products, weakened the association with alcohol and fruits, and strengthened the association with fish.Conclusions: Ecologic associations between food availability and disease vary considerably on the basis of whether mortality or incidence rates are used in the analysis. Great care is thus necessary when interpreting our results.
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Spatial econometrics has been criticized by some economists because some model specifications have been driven by data-analytic considerations rather than having a firm foundation in economic theory. In particular this applies to the so-called W matrix, which is integral to the structure of endogenous and exogenous spatial lags, and to spatial error processes, and which are almost the sine qua non of spatial econometrics. Moreover it has been suggested that the significance of a spatially lagged dependent variable involving W may be misleading, since it may be simply picking up the effects of omitted spatially dependent variables, incorrectly suggesting the existence of a spillover mechanism. In this paper we review the theoretical and empirical rationale for network dependence and spatial externalities as embodied in spatially lagged variables, arguing that failing to acknowledge their presence at least leads to biased inference, can be a cause of inconsistent estimation, and leads to an incorrect understanding of true causal processes.
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This paper analyses the differential impact of human capital, in terms of different levels of schooling, on regional productivity and convergence. The potential existence of geographical spillovers of human capital is also considered by applying spatial panel data techniques. The empirical analysis of Spanish provinces between 1980 and 2007 confirms the positive impact of human capital on regional productivity and convergence, but reveals no evidence of any positive geographical spillovers of human capital. In fact, in some specifications the spatial lag presented by tertiary studies has a negative effect on the variables under consideration.
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OBJECTIVE: The hyperglycemic hyperinsulinemic clamp technique using intraduodenally infused glucose is an attractive tool for studying postprandial glucose metabolism under strictly controlled conditions. Because it requires the use of somatostatin (SST), we examined, in this study, the effect of SST on intestinal glucose absorption. CONTEXT: Twenty-six normal volunteers were given a constant 3-h intraduodenal infusion of glucose (6 mg.kg(-1).min(-1)) labeled with [2-(3)H]glucose for glucose absorption measurement. During glucose infusion, 19 subjects received iv SST at doses of 10-100 ng.kg(-1).min(-1) plus insulin and glucagon, and seven subjects were studied under control conditions. In the controls, glucose was absorbed at a rate that, after a 20-min lag period, equaled the infusion rate. RESULTS: With all the doses of SST tested, absorption was considerably delayed but equaled the rate of infusion after 3 h. At that time, only 5 +/- 2% of the total amount of infused glucose was unabsorbed in the control subjects vs. 36 +/- 2% (P < 0.001) in the SST-infused subjects. In the latter, the intraluminal residue was almost totally absorbed within 40 min of the cessation of SST infusion. At the lowest dose of SST tested (10 ng.kg(-1).min(-1)), suppression of insulin secretion was incomplete. CONCLUSION: These properties of SST hamper the use of intraduodenal hyperglycemic hyperinsulinemic clamps as a tool for exploring postprandial glucose metabolism.
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This study investigated the direction of effects of temporal and downward social comparisons on self-rated health in very old age. Self-rated health can either reinforce or hinder comparison processes. In the framework of the Swiss Interdisciplinary Longitudinal Study on the Oldest Old, individuals aged 80 to 84 at baseline were interviewed and followed longitudinally for 5 years. Multilevel analyses were used to test the relative importance of temporal and social comparisons on self-rated health evaluations synchronically and diachronically (with a time lag of 12 to 18 months) as well as the direction of these relative influences. Results indicate that (a) at the synchronic level, continuity temporal comparisons have more impact than downward social comparisons on self-rated health; (b) both types of comparison had an independent and positive effect on self-rated health at the diachronic level; (c) self-rated health has an independent synchronic effect on both types of comparison and an independent diachronic effect in temporal comparison.
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Rekapitulation der Thesen und Ergebnisse In den nachfolgenden Abschnitten werden zur besseren Übersicht nochmals die zentralen Gesichtspunkte der Untersuchung und der wichtigsten Resultate zusammengefasst Zum Schluss werden die Untersuchungsergebnisse noch unter dem Blickwinkel ihrer praktischen Konsequenzen für die Umsetzung einzelner drogenpolitischer Zielsetzungen ausgewertet und die Problembereiche identifiziert, welche zusätzliche Forschungsanstrengungen erforderlich machen A Theoriebildung und Forschungsansatz Die Untersuchung verwendet einen multimodalen methodischen Ansatz (direkte Befragung Strafaktenanalyse und Auswertung amtlicher Statistiken) zur Analyse typischer Anpassungsmechanismen und konkreter Handlungsstrategien als Reaktion auf den behördliche Repression des lokalen Drogenmarktgeschehens Sie fokussiert auf den Kreis regelmäßiger Heroin und/oder Kokainkonsumenten die sich zeitweilig an bekannten Treffpunkten der sogenannten <
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We study comparative statics of manipulations by women in the men-proposing deferred acceptance mechanism in the two-sided one-to-one marriage market. We prove that if a group of women employs truncation strategies or weakly successfully manipulates, then all other women weakly benefit and all men are weakly harmed. We show that our results do not appropriately generalize to the many-to-one college admissions model.
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It has been argued that by truncating the sample space of the negative binomial and of the inverse Gaussian-Poisson mixture models at zero, one is allowed to extend the parameter space of the model. Here that is proved to be the case for the more general three parameter Tweedie-Poisson mixture model. It is also proved that the distributions in the extended part of the parameter space are not the zero truncation of mixed poisson distributions and that, other than for the negative binomial, they are not mixtures of zero truncated Poisson distributions either. By extending the parameter space one can improve the fit when the frequency of one is larger and the right tail is heavier than is allowed by the unextended model. Considering the extended model also allows one to use the basic maximum likelihood based inference tools when parameter estimates fall in the extended part of the parameter space, and hence when the m.l.e. does not exist under the unextended model. This extended truncated Tweedie-Poisson model is proved to be useful in the analysis of words and species frequency count data.
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Activation of the mitogen-activated protein (MAP) kinase cascade by progesterone in Xenopus oocytes leads to a marked down-regulation of activity of the amiloride-sensitive epithelial sodium channel (ENaC). Here we have studied the signaling pathways involved in progesterone effect on ENaC activity. We demonstrate that: (i) the truncation of the C termini of the alphabetagammaENaC subunits results in the loss of the progesterone effect on ENaC; (ii) the effect of progesterone was also suppressed by mutating conserved tyrosine residues in the Pro-X-X-Tyr (PY) motif of the C termini of the beta and gamma ENaC subunits (beta(Y618A) and gamma(Y628A)); (iii) the down-regulation of ENaC activity by progesterone was also suppressed by co-expression ENaC subunits with a catalytically inactive mutant of Nedd4-2, a ubiquitin ligase that has been previously demonstrated to decrease ENaC cell-surface expression via a ubiquitin-dependent internalization/degradation mechanism; (iv) the effect of progesterone was significantly reduced by suppression of consensus sites (beta(T613A) and gamma(T623A)) for ENaC phosphorylation by the extracellular-regulated kinase (ERK), a MAP kinase previously shown to facilitate the binding of Nedd4 ubiquitin ligases to ENaC; (v) the quantification of cell-surface-expressed ENaC subunits revealed that progesterone decreases ENaC open probability (whole cell P(o), wcP(o)) and not its cell-surface expression. Collectively, these results demonstrate that the binding of active Nedd4-2 to ENaC is a crucial step in the mechanism of ENaC inhibition by progesterone. Upon activation of ERK, the effect of Nedd4-2 on ENaC open probability can become more important than its effect on ENaC cell-surface expression.