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Crucial Determinant (crucial + determinant)
Selected AbstractsLabour market institutions and income inequalityECONOMIC POLICY, Issue 56 2008Daniele Checchi SUMMARY Institutions and inequality Labour market institutions are a crucial determinant of wage inequality, the wage share in aggregate income, and the unemployment rate. Since these variables affect, in turn, the distribution of income across households, the question arises of whether stronger labour market institutions have an impact on income inequality. Institutions can in principle have conflicting effects. For example, a higher unemployment benefit tends to increase the wage share, which in turn reduces inequality, but it also increases the unemployment rate thus making the distribution of income more unequal. This paper examines what is the overall impact of labour market institutions on household income inequality. The evidence indicates that stronger institutions are associated with lower income inequality, but in some cases also with higher rates of unemployment. We explore the magnitude of this trade-off, and quantify the changes in inequality and unemployment that we would observe if a common labour standard were imposed on members of the European Union. , Daniele Checchi and Cecilia García-Peńalosa [source] Differential effects of NT-4, NGF and BDNF on development of neurochemical architecture and cell size regulation in rat visual cortex during the critical periodEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2007Maren Engelhardt Abstract Development of inhibition is a crucial determinant of the time course of visual cortical plasticity. BDNF strongly affects interneuron development and the onset and closure of the critical period for ocular dominance plasticity. Less is known on the effects of NT-4 despite a clear involvement in ocular dominance plasticity. We have investigated the effects of NT-4 on interneuron development by supplying NT-4 with osmotic minipumps during two time windows overlapping the onset (P12,20) and the peak (P20,28) of the critical period. We assessed the expression of interneuronal markers and soma size maturation either after the end of the infusion periods or at the end of the critical period (P45). We found that NT-4 was very effective in regulating interneuron development. NPY, SOM and PARV neuron somata grew faster during both infusion periods whereas CR neurons only responded during the early infusion period. The effects of soma size elicited during the earlier infusion period were still present at P45. In PARV neurons, NT-4 caused a long-lasting stabilization of CB and NPY expression. Furthermore, NT-4 accelerated the expression of GAD-65 mRNA in a subset of non-PARV neurons of layer V, which normally up-regulate GAD-65 towards the end of the critical period. Most of these effects were shared by NT-4 and BDNF. Some were unexpectedly also shared by NGF, which promoted growth of layer V PARV neurons, stabilized the CB expression and accelerated the GAD-65 expression. The results suggest that neurotrophins act on critical period plasticity by strengthening inhibition. [source] ,Seek and ye shall find': antecedents of assimilation and contrast in social comparisonEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 5 2001Thomas Mussweiler Based on a Selective Accessibility (SA) model of comparison consequences, it is suggested that the self-evaluative effects of social comparisons depend on the nature of the hypothesis that is tested as a starting-point of the comparison process. If judges test the hypothesis that they are similar to the standard, then standard-consistent self-knowledge is rendered accessible so that self-evaluations are assimilated towards the standard. If judges test the hypothesis that they are dissimilar from the standard, however, standard-inconsistent self-knowledge is made accessible so that self-evaluations are contrasted away from the standard. These predictions are tested by inducing participants to test for similarity versus dissimilarity to the standard via a procedural priming manipulation. Consistent with the SA model, assimilation occurs if participants are procedurally primed to focus on similarities to the standard, whereas contrast results if they are primed to focus on dissimilarities. These findings suggest that similarity versus dissimilarity testing is a crucial determinant of assimilation versus contrast. It is proposed that distinguishing between these two alternative hypotheses may provide an integrative framework for an understanding of the self-evaluative consequences of social comparisons. Copyright © 2001 John Wiley & Sons, Ltd. [source] The Interleukin-1 RN Polymorphism and Helicobacter pylori Infection in the Development of Duodenal UlcerHELICOBACTER, Issue 6 2004Ping-I Hsu ABSTRACT Background., The host genetic factors that determine the clinical outcomes for Helicobacter pylori -infected individuals remain unclear. Aims., To elucidate the relations among interleukin-1 locus polymorphisms, and H. pylori infection in the development of duodenal ulcers. Materials and methods., In a case,control study involving 168 control subjects and 147 patients with duodenal ulcer, biallelic polymorphisms of two interleukin-1 loci, IL-1B,511 and IL-1B+3954, as well as the penta-allelic variable number of tandem repeats of interleukin-1 receptor antagonist IL-1RN, were genotyped, and the H. pylori states of controls and patients were examined. Results.,Helicobacter pylori infection, male gender and the carriage of IL-1RN*2 independently increased the risk of duodenal ulcer with odds ratios of 6.4 (95% confidence interval, 3.7,11.0), 1.9 (95% confidence interval, 1.1,3.4) and 2.7 (95% confidence interval, 1.1,6.8), respectively. Statistical analysis revealed an interaction between IL-1RN*2 and H. pylori infection with the duodenal ulcer risk conferred by the H. pylori infection substantially increased (odds ratios, 22.6; 95% confidence interval, 5.9,86.5) by the carriage of IL-1RN*2. In addition, a synergistic interaction between IL-1RN*2 and blood group O existed. The combined risk of H. pylori infection, the carriage of IL-1RN*2 and blood group O for duodenal ulcer was 27.5 (95% confidence interval, 3.1,243.6). Conclusions., This work is the first to verify IL-1RN*2 as an independent factor that governs the development of duodenal ulcers. Our data indicate that H. pylori infection and IL-1RN*2 synergistically determine susceptibility to duodenal ulcer. The blood group phenotype is possibly a crucial determinant for the outcome of the impact of an interleukin-1 locus polymorphism on H. pylori -infected individuals. [source] Neural systems connecting interoceptive awareness and feelingsHUMAN BRAIN MAPPING, Issue 1 2007Olga Pollatos Abstract In many theories of emotions the representations of bodily responses play an important role for subjective feelings. We tested the hypothesis that the perception of bodily states is positively related to the experienced intensity of feelings as well as to the activity of first-order and second-order brain structures involved in the processing of feelings. Using a heartbeat perception task, subjects were separated into groups with either high or poor interoceptive awareness. During emotional picture presentation we measured high-density EEG and used spatiotemporal current density reconstruction to identify regions involved in both interoceptive awareness and emotion processing. We observed a positive relation between interoceptive awareness and the experienced intensity of emotions. Furthermore, the P300 amplitudes to pleasant and unpleasant pictures were enhanced for subjects with high interoceptive awareness. The source reconstruction revealed that interoceptive awareness is related to an enhanced activation in both first-order structures (insula, somatosensory cortices) and second-order structures (anterior cingulate, prefrontal cortices). We conclude that the perception of bodily states is a crucial determinant for the processing and the subjective experience of feelings. Hum. Brain Mapping, 2007. © 2006 Wiley-Liss, Inc. [source] Developmental control via GATA factor interplay at chromatin domainsJOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2005Emery H. Bresnick Despite the extraordinary task of packaging mammalian DNA within the constraints of a cell nucleus, individual genes assemble into cell type-specific chromatin structures with high fidelity. This chromatin architecture is a crucial determinant of gene expression signatures that distinguish specific cell types. Whereas extensive progress has been made on defining biochemical and molecular mechanisms of chromatin modification and remodeling, many questions remain unanswered about how cell type-specific chromatin domains assemble and are regulated. This mini-review will discuss emerging studies on how interplay among members of the GATA family of transcription factors establishes and regulates chromatin domains. Dissecting mechanisms underlying the function of hematopoietic GATA factors has revealed fundamental insights into the control of blood cell development from hematopoietic stem cells and the etiology of pathological states in which hematopoiesis is perturbed. © 2005 Wiley-Liss, Inc. [source] Structural change in the West German agricultural sectorAGRICULTURAL ECONOMICS, Issue 2009Silke Huettel Structural change; Strategic competition; Land market; Markov chain Abstract This article explains regionally differentiated patterns of structural change based on a theoretical framework dealing with strategic interaction of farms on the land market. The main research question focuses on the causes of regionally persistent structures. An empirical Markov chain model is defined for the West German agricultural sector. The model is used to explain the probabilities of farm growth, decline, or exit in terms of the current and former regional farm size structure. Further, the impact of variables describing the regional farm structure, thereby indicating market power of the large, the potential of high competition for land within a region, and possibly high rents of the status quo in combination with sunk costs, is quantified. The results confirm the relevance of strategic interaction as a crucial determinant of persistent regional differences in the farm size structure over time. [source] Repartnering after first union disruptionJOURNAL OF MARRIAGE AND FAMILY, Issue 1 2005Zheng Wu Using data from the 1995 General Social Survey (N= 2,639), this study examines two competing repartnering choices made by Canadians after first union disruption: marriage or cohabitation. About 42% of women and 54% of men form a second union 5 years after union disruption, with cohabitation being the most prevalent choice. The timing of second union formation is more rapid among former cohabitors than among the divorced. Widowhood is an acute barrier to repartnering. Gender is the most crucial determinant in the repartnering process; men have a higher rate of second union formation than women. The hazard rate of second union formation also varies by age at union disruption, duration of the first union, prior fertility (for men only), education, employment, and religion. [source] The influence of density on post-weaning growth in roe deer Capreolus capreolus fawnsJOURNAL OF ZOOLOGY, Issue 3 2002A. J. M. Hewison Abstract In temperate ungulates, the body weight of juveniles at the onset of winter is a crucial determinant of survival and can also influence subsequent reproductive success. However, growth may be retarded post-weaning, during winter, as a result of resource restriction and/or the demands of thermoregulation in harsh climatic conditions. Post-weaning growth rates of juveniles were compared in relation to varying density in two populations of roe deer Capreolus capreolus (Chizé, Dourdan) monitored for 10 and 15 years, respectively. Body growth of fawns continued over the post-weaning stage of the juvenile period (October,March) at the rate of 0.017 kg/day at Chizé and 0.014 kg/day at Dourdan. Deer density had no influence on this post-weaning growth rate of juveniles in their first winter. However, deer born in years of high density weighed less at a given date than those born in years of low density because of their smaller body size at the onset of winter, indicating density-dependent rates of growth before weaning. At Chizé, the sexes grew at the same rate, but sexual dimorphism was apparent as males weighed about 1 kg (8%) more than females at a given date. At Dourdan, no significant sexual dimorphism was detected, although females tended to be heavier than males at a given date. We conclude that density influences juvenile body weight (through its effect on birth weight and/or post-natal growth rate) before weaning in this species and, despite continued growth after weaning, during winter, roe deer whose early growth is limited through interspecific competition cannot compensate for this early restriction. [source] Iron K, line profiles and the inner boundary condition of accretion flowsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2003A. Merloni ABSTRACT Recent X-ray observations have shown evidence for exceptionally broad and skewed iron K, emission lines from several accreting black hole systems. The lines are assumed to be due to fluorescence of the accretion disc illuminated by a surrounding corona and require a steep emissivity profile increasing into the innermost radius. This appears to question both standard accretion disc theory and the zero-torque assumption for the inner boundary condition, both of which predict a much less extreme profile. Instead it argues that a torque may be present due to magnetic coupling with matter in the plunging region or even to the spinning black hole itself. Discussion so far has centred on the torque acting on the disc. However, the crucial determinant of the iron line profile is the radial variation of the power radiated in the corona. Here we study the effects of different inner boundary conditions on the coronal emissivity and on the profiles of the observable Fe K, lines. We argue that in the extreme case where a prominent highly redshifted component of the iron line is detected, requiring a steep emissivity profile in the innermost part and a flatter one outside, energy from the gas plunging into the black hole is being fed directly to the corona. [source] Stably folded de novo proteins from a designed combinatorial libraryPROTEIN SCIENCE, Issue 1 2003Yinan Wei Abstract Binary patterning of polar and nonpolar amino acids has been used as the key design feature for constructing large combinatorial libraries of de novo proteins. Each position in a binary patterned sequence is designed explicitly to be either polar or nonpolar; however, the precise identities of these amino acids are varied extensively. The combinatorial underpinnings of the "binary code" strategy preclude explicit design of particular side chains at specified positions. Therefore, packing interactions cannot be specified a priori. To assess whether the binary code strategy can nonetheless produce well-folded de novo proteins, we constructed a second-generation library based upon a new structural scaffold designed to fold into 102-residue four-helix bundles. Characterization of five proteins chosen arbitrarily from this new library revealed that (1) all are ,-helical and quite stable; (2) four of the five contain an abundance of tertiary interactions indicative of well-ordered structures; and (3) one protein forms a well-folded structure with native-like features. The proteins from this new 102-residue library are substantially more stable and dramatically more native-like than those from an earlier binary patterned library of 74-residue sequences. These findings demonstrate that chain length is a crucial determinant of structural order in libraries of de novo four-helix bundles. Moreover, these results show that the binary code strategy,if applied to an appropriately designed structural scaffold,can generate large collections of stably folded and/or native-like proteins. [source] Evolution and modulation of intracellular calcium release during long-lasting, depleting depolarization in mouse muscleTHE JOURNAL OF PHYSIOLOGY, Issue 19 2008Leandro Royer Intracellular calcium signals regulate multiple cellular functions. They depend on release of Ca2+ from cellular stores into the cytosol, a process that in many types of cells appears to be tightly controlled by changes in [Ca2+] within the store. In contrast with cardiac muscle, where depletion of Ca2+ in the sarcoplasmic reticulum is a crucial determinant of termination of Ca2+ release, in skeletal muscle there is no agreement regarding the sign, or even the existence of an effect of SR Ca2+ level on Ca2+ release. To address this issue we measured Ca2+ transients in mouse flexor digitorum brevis (FDB) skeletal muscle fibres under voltage clamp, using confocal microscopy and the Ca2+ monitor rhod-2. The evolution of Ca2+ release flux was quantified during long-lasting depolarizations that reduced severely the Ca2+ content of the SR. As in all previous determinations in mammals and non-mammals, release flux consisted of an early peak, relaxing to a lower level from which it continued to decay more slowly. Decay of flux in this second stage, which has been attributed largely to depletion of SR Ca2+, was studied in detail. A simple depletion mechanism without change in release permeability predicts an exponential decay with time. In contrast, flux decreased non-exponentially, to a finite, measurable level that could be maintained for the longest pulses applied (1.8 s). An algorithm on the flux record allowed us to define a quantitative index, the normalized flux rate of change (NFRC), which was shown to be proportional to the ratio of release permeability P and inversely proportional to Ca2+ buffering power B of the SR, thus quantifying the ,evacuability' or ability of the SR to empty its content. When P and B were constant, flux then decayed exponentially, and NFRC was equal to the exponential rate constant. Instead, in most cases NFRC increased during the pulse, from a minimum reached immediately after the early peak in flux, to a time between 200 and 250 ms, when the index was no longer defined. NFRC increased by 111% on average (in 27 images from 18 cells), reaching 300% in some cases. The increase may reflect an increase in P, a decrease in B, or both. On experimental and theoretical grounds, both changes are to be expected upon SR depletion. A variable evacuability helps maintain a constant Ca2+ output under conditions of diminishing store Ca2+ load. [source] Modelling opportunity in health under partial observability of circumstancesHEALTH ECONOMICS, Issue 3 2010Pedro Rosa Dias Abstract This paper proposes a behavioural model of inequality of opportunity in health that integrates John Roemer's framework of inequality of opportunity with the Grossman model of health capital and demand for health. The model generates a recursive system of equations for health and lifestyles, which is then jointly estimated by full information maximum likelihood with freely correlated error terms. The analysis innovates by accounting for the presence of unobserved heterogeneity, therefore addressing the partial-circumstance problem, and by extending the examination of inequality of opportunity to health outcomes other than self-assessed health, such as long-standing illness, disability and mental health. The results provide evidence for the existence of third factors that simultaneously influence health outcomes and lifestyle choices, supporting the empirical relevance of the partial-circumstance problem. Accounting for these factors, the paper corroborates that the effect of parental and early circumstances on adult health disparities is paramount. However, the particular set of circumstances that affect each of the analysed health outcomes differs substantially. The results also show that differences in educational opportunities, and in social development in childhood, are crucial determinants of lifestyles in adulthood, which, in turn, shape the observed health inequalities. Copyright © 2010 John Wiley & Sons, Ltd. [source] Vascular and dendritic cell coagulation signaling in sepsis progressionJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 2009W. RUF Summary., The intrinsic signaling networks of the coagulation pathways have recently emerged as crucial determinants for survival in sepsis and systemic inflammatory response syndromes. Protease activated receptor (PAR) 1 is central to both lethality promoting and vascular protective signaling. In the vascular anticoagulant pathway, EPCR/aPC-PAR1 signaling prevents vascular leakage and genetic or acute deficiencies in this pathway promote lethality. In addition, coagulation signaling acts directly on cells of the innate immune system. Dendritic cell (DC) thrombin-PAR1 signaling is coupled to the migration promoting sphingosine 1 phosphate receptor 3 (S1P3). Thrombin generated in the lymphatic compartment perturbs DCs to promote systemic inflammation and disseminated intravascular coagulation in severe sepsis. Signaling-selective aPC variants and selective modulators of the S1P receptor system attenuate sepsis lethality, suggesting novel therapeutic approaches that can be employed to rebalance alterations in the coagulation signaling pathways in severe inflammatory disorders. [source] PROLIFERATION OF ACADEMIC JOURNALS: EFFECTS ON RESEARCH QUANTITY AND QUALITYMETROECONOMICA, Issue 4 2007Rajeev K. Goel ABSTRACT There have been significant structural changes in research markets in recent years reflected in the increase in the number of academic journals. This paper uses a differential game model of authors and journal editors to examine the effects of an increase in competition among academic journals. Does an increase in the number of academic journals lead to an increase in scholarly articles published? Will an increase in publishing outlets adversely affect research quality? The results show greater competition does not affect research output and in fact enhances research quality. The number of journals and the relative discount rates of authors and editors are crucial determinants of the effects of competition. [source] Wages and Ageing: Is There Evidence for the ,Inverse-U' Profile?,OXFORD BULLETIN OF ECONOMICS & STATISTICS, Issue 3 2010Micha Abstract How individual wages change with time is one of the crucial determinants of labour market decisions including the timing of retirement. The focus of this paper is the relationship between age and wages with special attention given to individuals nearing retirement. The analysis is presented in a comparative context for Britain and Germany looking at two longitudinal data sets (BHPS and SOEP, respectively) for the years 1995,2004. We show the importance of cohort effects and selection out of employment which determine the downward-sloping part of the ,inverse-U' profile observed in cross-sections. There is little evidence that wages fall with age. [source] | ||||||||||||||||