951 resultados para Vine decline
Resumo:
Recently, age-related hippocampal (HP) volume loss could be associated with a decrease in general fluid intelligence (gF). In the present study we investigated whether and how extensive musical training modulates human HP volume and gF performance. Previously, some studies demonstrated positive effects of musical training on higher cognitive functions such as learning and memory, associated with neural adaptations beyond the auditory domain. In order to detect possible associations between musical training and gF, we bilaterally segmented the HP formation and assessed the individual gF performance of people with different levels of musical expertise. Multiple regression analyses revealed that HP volume predicts gF in musicians but not in nonmusicians; in particular, bilaterally enhanced HP volume is associated with increased gF exclusively in musically trained people (amateurs and experts). This result suggests that musical training facilitates the recruitment of cognitive resources, which are essential for gF and linked to HP functioning. Musical training, even at a moderate level of intensity, can thus be considered as a potential strategy to decelerate age-related effects of cognitive decline. © 2013 Wiley Periodicals, Inc.
Resumo:
In 1921 Mexico produced a quarter of world s petroleum, making the country the secondlargest producer in the world, but by 1930 it only accounted for 3 per cent of world sproduction. To date the discussion has mostly relied on events taking place in Mexico forexplaining the decline of the industry. Very little attention has been placed todevelopments in petroleum industry elsewhere, except Venezuela. Practically noattention has been paid to the reasons for the rise of oil output in Mexico. This neglectsthe massive changes taking place in the petroleum industry worldwide during the GreatWar years and its aftermath, and overall ignores the shortage of oil that occurred in theworld s markets between 1918-1921. These are crucial events in order to understand theearly rise of the Mexican oil industry and set the basis for a better understanding of thesubsequent sudden decline.
Resumo:
This paper presents a new framework for studying irreversible (dis)investment whena market follows a random number of random-length cycles (such as a high-tech productmarket). It is assumed that a firm facing such market evolution is always unsure aboutwhether the current cycle is the last one, although it can update its beliefs about theprobability of facing a permanent decline by observing that no further growth phasearrives. We show that the existence of regime shifts in fluctuating markets suffices for anoption value of waiting to (dis)invest to arise, and we provide a marginal interpretationof the optimal (dis)investment policies, absent in the real options literature. Thepaper also shows that, despite the stochastic process of the underlying variable has acontinuous sample path, the discreteness in the regime changes implies that the samplepath of the firm s value experiences jumps whenever the regime switches all of a sudden,irrespective of whether the firm is active or not.
Resumo:
In this chapter we portray the effects of female education and professional achievementon fertility decline in Spain over the period 1920-1980 (birth cohorts of 1900-1950).A longitudinal econometric approach is used to test the hypothesis that the effectsof women s education in the revaluing of their time had a very significant influence onfertility decline. Although in the historical context presented here improvements inschooling were on a modest scale, they were continuous (with the interruption of theCivil War) and had a significant impact in shaping a model of low fertility in Spain. Wealso stress the relevance of this result in a context such as the Spanish for which liberalvalues were absent, fertility control practices were forbidden, and labour forceparticipation of women was politically and socially constrained.
Resumo:
Many authors have discussed a decline in internal labor markets and an apparent shift to a new employment contract, characterized by less commitment between employer and employee and more portable skills. These discussions occur without much evidence on what employment contract employees currently feel is fair. We perfomed quasi-experimental surveys to study when employees in the U.S. andCanada feel that layoffs are fair.Layoffs were perceived as more fair if they were due to lower product demand than if the result of employee suggestions. This result appears to be solely due to norms of reciprocity (companiesshould not punish employees for their efforts), rather than norms of sharing rents, as new technology was also considered a justification for layoffs.Consistent with theories of distributive and procedural equity, layoffs were perceived as more fair if the CEO voluntarily shared the pain. CEO bonuses due to layoffs lowered their reported fairness only slightly.Respondents in Silicon Valley were not more accepting of layoffsthan were those in Canada on average, although the justificationsconsidered valid differed slightly.
Resumo:
Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.
Resumo:
Cette recherche investigue l'impact de la transition à la parentalité sur l'identité conjugale. Afin de mettre en évidence les bouleversements induits par l'arrivée du premier enfant sur le système-couple, deux groupes de sujets ont constitué notre échantillon : des couples parents d'un premier enfant âgé de 9 à 12 mois et des couples sans enfant mais avec une durée de vie commune équivalente au premier groupe. Chaque couple a été rencontré dans le cadre d'un unique entretien. Leur première tâche a été de décrire leurs vies de couple passée et actuelle au travers de valeurs et devises. Un questionnaire créé pour cette recherche a ensuite permis d'évaluer la représentation des conjoints quant à l'évolution de leur couple, et ce sur la base de cinq dimensions à même de caractériser la manière d'être ensemble des conjoints. Finalement, les jeunes parents ont participé à un entretien semi-directif afin de témoigner des changements personnels et de couple vécus dans le cadre de la transition à la parentalité. Des analyses qualitatives et quantitatives basées sur les données récoltées au travers de nos trois outils révèlent plusieurs résultats. Les conjoints sans enfant décrivent avant tout leur couple comme un cocon au sein duquel deux individus autonomes trouvent refuge et réconfort. Les jeunes parents se démarquent quant à eux par une diminution de leur sentiment d'indépendance, reflet de la nécessaire collaboration propre au co-parentage. Une analyse des entretiens semi-structurés croisée avec l'évaluation du degré de satisfaction conjugale permet le constat suivant : la diminution avérée de la satisfaction conjugale lors de la transition à la parentalité n'est pas strictement associée aux bouleversements conjugaux. Ce déclin lors de l'arrivée et de l'accueil du premier enfant semble en effet être également en lien avec une difficile articulation, chez chaque partenaire, de leurs identités personnelle, conjugale, parentale et socio-professionnelle. - This research investigates the impact of the transition to parenthood on marital identity. To highlight the changes brought about by the arrival of the first child on the couple, two groups of subjects constituted our sample: couples with a first child of 9 to 12 months and childless couples but with a period of cohabitation equivalent to that of the first group. Each couple was interviewed once only. Their first task was to describe their lives as a couple past and present through values and principles. A questionnaire devised for this research was then used to evaluate partners' responses regarding the evolution of their relationship, this based on five criteria to characterise the couples' way of being together. Finally, young parents participated in a semi- structured interview to describe personal changes and those as a couple experienced in the transition to parenthood. Qualitative and quantitative analyses based on data collected through our three tools reveal several results. Spouses without children describe their relationship primarily as a cocoon in which two autonomous individuals find refuge and comfort. Young parents differ in reducing their feelings of independence, reflecting the collaborative needs specific to co-parenting. An analysis of the semi- structured interviews crossed with the assessment of marital satisfaction gives rise to the following observation: the pronounced reduction in marital satisfaction during the transition to parenthood is not strictly associated with marital disruption. This decline upon the arrival of the first child seems to be in line with a difficult balance for each partner between their personal, marital, parental and socio- professional identities.
Resumo:
BACKGROUND: Food allergy has reached an epidemic level in westernized countries and although central mechanisms have been described, the variability associated with genetic diversity underscores the still unresolved complexity of these disorders. OBJECTIVE: To develop models of food allergy and oral tolerance, both strictly induced by the intestinal route, and to compare antigen-specific responses. METHODS: BALB/c mice were mucosally sensitized to ovalbumin (OVA) in the presence of the mucosal adjuvant cholera toxin, or tolerized by intra-gastric administrations of OVA alone. Antibody titres and cytokines were determined by ELISA, and allergic status was determined through several physiologic parameters including decline in temperature, diarrhoea, mast cell degranulation and intestinal permeability. RESULTS: OVA-specific antibodies (IgE, IgGs and IgA in serum and feces) were produced in sensitized mice exclusively. Upon intra-gastric challenge with OVA, sensitized mice developed anaphylactic reactions associated with a decline of temperature, diarrhoea, degranulation of mast cells, which were only moderately recruited in the small intestine, and increased intestinal permeability. Cytokines produced by immune cells from sensitized mice included T-helper type 2 cytokines (IL-5, IL-13), but also IL-10, IFN-gamma and IL-17. In contrast, all markers of allergy were totally absent in tolerized animals, and yet the latter were protected from subsequent sensitization, demonstrating that oral tolerance took place efficiently. CONCLUSION: This work allows for the first time an appropriate comparison between sensitized and tolerized BALB/c mice towards OVA. It highlights important differences from other models of allergy, and thus questions some of the generally accepted notions of allergic reactions, such as the protective role of IFN-gamma, the importance of antigen-specific secretory IgA and the role of mucosal mast cells in intestinal anaphylaxis. In addition, it suggests that IL-17 might be an effector cytokine in food allergy. Finally, it demonstrates that intestinal permeability towards the allergen is increased during challenge.
Resumo:
Stable isotopes of carbonates (delta(13)C(carb), delta(18)O(carb)), organic matter (delta(13)C(org), delta(15)N(org)) and major, trace and rare earth element (REE) compositions of marine carbonate rocks of Late Permian to Early Triassic age were used to establish the position of the Permian-Triassic boundary (PTB) at two continuous sections in the Velebit Mountain, Croatia. The chosen sections - Rizvanusa and Brezimenjaca - are composed of two lithostratigraphic units, the Upper Permian Transitional Dolomite and the overlying Sandy Dolomite. The contact between these units, characterized by the erosional features and sudden occurrence of ooids and siliciclastic grains, was previously considered as the chronostratigraphic PTB. The Sandy Dolomite is characterized by high content of non-carbonate material (up to similar to 30 wt.% insoluble residue), originated from erosion of the uplifted hinterland. A relatively rich assemblage of Permian fossils (including Geinitzina, Globivalvulina, Hemigordius, bioclasts of gastropods, ostracods and brachiopods) was found for the first time in Sandy Dolomite, 5 m above the lithologic boundary in the Rizvanusa section. A rather abrupt negative delta(13)C(carb) excursion in both sections appears in rocks showing no recognizable facies change within the Sandy Dolomite, -2 parts per thousand at Rizvanusa and -1.2 parts per thousand at Brezimenjaca, 11 m and 0.2 m above the lithologic contact, respectively. This level within the lower part of the Sandy Dolomite is proposed as the chemostratigraphic PTB. In the Rizvanusa section, the delta(13)C(org) values decline gradually from similar to-25 parts per thousand in the Upper Permian to similar to-29 parts per thousand in the Lower Triassic. The first negative delta(13)C(org) excursion occurs above the lithologic contact, within the uppermost Permian deposits, and appears to be related to the input of terrigenous material. The release of isotopically light microbial soil-biomass into the shallow-marine water may explain this sudden decrease of delta(13)C(org) values below the PTB. This would support the hypothesis that in the western Tethyan realm the land extinction, triggering a sudden drop of woody vegetation and related land erosion, preceded the marine extinction. The relatively low delta(15)N(org) values at the Permian-Triassic (P-Tr) transition level, close to approximate to 0 parts per thousand, and a secondary negative delta(13)C(org) excursion of -0.5 parts per thousand point to significant terrestrial input and primary contribution of cyanobacteria. The profiles of the concentrations of redox-sensitive elements (Ce, Mn, Fe, V), biogenic or biogenic-scavenged elements (P, Ba, Zn, V), Ce/Ce* values, and normalized trace elements, including Ba/Al, Ba/Fe, Ti/Al, Al/(Al + Fe + Mn) and Mn/Ti show clear excursions at the Transitional Dolomite-Sandy Dolomite lithologic boundary and the chemostratigraphic P-Tr boundary. The stratigraphic variations indicate a major regression phase marking the lithologic boundary, transgressive phases in the latest Permian and a gradual change into shallow/stagnant anoxic marine environment towards the P-Tr boundary level and during the earliest Triassic. (C) 2010 Elsevier B.V. All rights reserved.
Resumo:
The treatments for ischemic stroke can only be administered in a narrow time-window. However, the ischemia onset time is unknown in ~30% of stroke patients (wake-up strokes). The objective of this study was to determine whether MR spectra of ischemic brains might allow the precise estimation of cerebral ischemia onset time. We modeled ischemic stroke in male ICR-CD1 mice using a permanent middle cerebral artery filament occlusion model with laser Doppler control of the regional cerebral blood flow. Mice were then subjected to repeated MRS measurements of ipsilateral striatum at 14.1 T. A striking initial increase in γ-aminobutyric acid (GABA) and no increase in glutamine were observed. A steady decline was observed for taurine (Tau), N-acetyl-aspartate (NAA) and similarly for the sum of NAA+Tau+glutamate that mimicked an exponential function. The estimation of the time of onset of permanent ischemia within 6 hours in a blinded experiment with mice showed an accuracy of 33±10 minutes. A plot of GABA, Tau, and neuronal marker concentrations against the ratio of acetate/NAA allowed precise separation of mice whose ischemia onset lay within arbitrarily chosen time-windows. We conclude that (1)H-MRS has the potential to detect the clinically relevant time of onset of ischemic stroke.
Resumo:
The aim of this contribution is to explore how the recent internationalization and the increasing importance of 'cosmopolitan capital' has impacted on the structure and character of the field of the Swiss business elite. For this purpose we will develop the notion of cosmopolitan capital and comparatively investigate the field of the Swiss business elite in 1980, 2000 and 2010 with multiple correspondence analysis. We can show that in this period international managers with transnational careers and networks not only grow in number, but come to conquer the apex of the biggest and highest capitalized Swiss firms. At the same time, national forms of capital decline in importance and Swiss managers themselves are differentiated increasingly into national and international fractions.
Resumo:
Es documenta la disminució de l’àrea de distribució i del nombre d’individus i s’avalua l’extensió actual d’Stachys maritima a la península Ibèrica, restringida a menys de 200 individus amb una àrea d’ocupació de només 8 km2. L’espècie és requalificada com a CR (en perill crític) en aquest territori, incrementant l’anterior valoració com a VU (vulnerable). Se suggereixen les mesures de conservació adequades que permetin garantir simultàniament activitats de turisme sostenibles
Resumo:
Over the last decades, a decline in motor skills and in physical activity and an increase in obesity has been observed in children. However, there is a lack of data in young children. We tested if differences in motor skills and in physical activity according to weight or gender were already present in 2- to 4-year-old children. Fifty-eight child care centers in the French part of Switzerland were randomly selected for the Youp'là bouge study. Motor skills were assessed by an obstacle course including 5 motor skills, derived from the Zurich Neuromotor Assessment test. Physical activity was measured with accelerometers (GT1M, Actigraph, Florida, USA) using age-adapted cut-offs. Weight status was assessed using the International Obesity Task Force criteria (healthy weight vs overweight) for body mass index (BMI). Of the 529 children (49% girls, 3.4 ± 0.6 years, BMI 16.2 ± 1.2 kg/m2), 13% were overweight. There were no significant weight status-related differences in the single skills of the obstacle course, but there was a trend (p = 0.059) for a lower performance of overweight children in the overall motor skills score. No significant weight status-related differences in child care-based physical activity were observed. No gender-related differences were found in the overall motor skills score, but boys performed better than girls in 2 of the 5 motor skills (p ≤ 0.04). Total physical activity as well as time spent in moderate-vigorous and in vigorous activity during child care were 12-25% higher and sedentary activity 5% lower in boys compared to girls (all p < 0.01). At this early age, there were no significant weight status- or gender-related differences in global motor skills. However, in accordance to data in older children, child care-based physical activity was higher in boys compared to girls. These results are important to consider when establishing physical activity recommendations or targeting health promotion interventions in young children.
Resumo:
ABSTRACT: Chronic Infantile Neurological Cutaneous Articular (CINCA) syndrome, also called Neonatal Onset Multisystem Inflammatory Disease (NOMID) is a chronic disease with early onset affecting mainly the central nervous system, bones and joints and may lead to permanent damage. We report two preterm infants with severe CINCA syndrome treated by anti-interleukin-1 in the neonatal period, although, so far, no experience with this treatment in infants younger than three months of age has been reported. A review of the literature was performed with focus on treatment and neonatal features of CINCA syndrome. CASE REPORT: Two cases suspected to have CINCA syndrome were put on treatment with anakinra in the early neonatal period due to severe clinical presentation. We observed a rapid and persistent decline of clinical signs and systemic inflammation and good drug tolerance. Diagnosis was confirmed in both cases by mutations in the NLRP3/CIAS1-gene coding for cryopyrin. As particular neonatal clinical signs polyhydramnios and endocardial overgrowth are to be mentioned. CONCLUSION: We strongly suggest that specific treatment targeting interleukin-1 activity should be started early. Being well tolerated, it can be introduced already in neonates presenting clinical signs of severe CINCA syndrome in order to rapidly control inflammation and to prevent life-long disability.
Resumo:
BACKGROUND: Pulmonary vascular diseases are increasingly recognised as important clinical conditions. Pulmonary hypertension associated with a range of aetiologies is difficult to treat and associated with progressive morbidity and mortality. Current therapies for pulmonary hypertension include phosphodiesterase type 5 inhibitors, endothelin receptor antagonists, or prostacyclin mimetics. However, none of these provide a cure and the clinical benefits of these drugs individually decline over time. There is, therefore, an urgent need to identify new treatment strategies for pulmonary hypertension. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that the PPARbeta/delta agonist GW0742 induces vasorelaxation in systemic and pulmonary vessels. Using tissue from genetically modified mice, we show that the dilator effects of GW0742 are independent of the target receptor PPARbeta/delta or cell surface prostacyclin (IP) receptors. In aortic tissue, vascular relaxant effects of GW0742 were not associated with increases in cGMP, cAMP or hyperpolarisation, but were attributed to inhibition of RhoA activity. In a rat model of hypoxia-induced pulmonary hypertension, daily oral dosing of animals with GW0742 (30 mg/kg) for 3 weeks significantly reduced the associated right heart hypertrophy and right ventricular systolic pressure. GW0742 had no effect on vascular remodelling induced by hypoxia in this model. CONCLUSIONS/SIGNIFICANCE: These observations are the first to show a therapeutic benefit of 'PPARbeta/delta' agonists in experimental pulmonary arterial hypertension and provide pre-clinical evidence to favour clinical trials in man.