883 resultados para Sufficient Condition


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There is mounting evidence that organic or inorganic enrichment of aquatic environments increases the risk of infectious diseases, with disease agents ranging from helminth parasites to fungal, bacterial, and viral pathogens. The causal link between microbial resource availability and disease risk is thought to be complex and, in the case of so-called "opportunistic pathogens," to involve additional stressors that weaken host resistance (e.g., temperature shifts or oxygen deficiencies). In contrast to this perception, our experiment shows that the link between resource levels and infection of fish embryos can be very direct: increased resource availability can transform benign microbial communities into virulent ones. We find that embryos can be harmed before further stresses (e.g., oxygen depletion) weaken them, and treatment with antibiotics and fungicides cancels the detrimental effects. The changed characteristics of symbiotic microbial communities could simply reflect density-dependent relationships or be due to a transition in life-history strategy. Our findings demonstrate that simple microhabitat changes can be sufficient to turn "opportunistic" into virulent pathogens.

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As fitness returns during a breeding attempt are context-dependent, parents are predicted to bias their food allocation within a brood from poor towards good condition nestlings when environmental conditions deteriorate. We tested this prediction in the Alpine swift and the European starling, two migratory bird species, by modifying an ultraviolet (UV) visual signal of condition in nestlings and exploring how parents allocate food to their young as the season progresses. We show in both species that: (i) UV light reflected by the body skin of offspring positively correlates with their stature (i.e. body mass and skeletal size) and (ii) parental favouritism towards young with more UV reflective skin gradually increases as the season progresses. Early-breeding parents supplied food preferentially to UV pale (i.e. small stature) nestlings, whereas late-breeding parents favoured UV bright offspring (i.e. large stature). These results emphasize that parents use UV signals of offspring condition to adjust their feeding strategies depending on the ecological context.

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BACKGROUND: Improved survival after prophylactic implantation of a defibrillator in patients with reduced left ventricular ejection fraction (EF) after myocardial infarction (MI) has been demonstrated in patients who experienced remote MIs in the 1990s. The absolute survival benefit conferred by this recommended strategy must be related to the current risk of arrhythmic death, which is evolving. This study evaluates the mortality rate in survivors of MI with impaired left ventricular function and its relation to pre-hospital discharge baseline characteristics. METHODS: The clinical records of patients who had sustained an acute MI between 1999 and 2000 and had been discharged from the hospital with an EF of < or = 40% were included. Baseline characteristics, drug prescriptions, and invasive procedures were recorded. Bivariate and multivariate analyses were performed using a primary end point of total mortality. RESULTS: One hundred sixty-five patients were included. During a median follow-up period of 30 months (interquartile range, 22 to 36 months) 18 patients died. The 1-year and 2-year mortality rates were 6.7% and 8.6%, respectively. Variables reflecting coronary artery disease and its management (ie, prior MI, acute reperfusion, and complete revascularization) had a greater impact on mortality than variables reflecting mechanical dysfunction (ie, EF and Killip class). CONCLUSIONS: The mortality rate among survivors of MIs with reduced EF was substantially lower than that reported in the 1990s. The strong decrease in the arrhythmic risk implies a proportional increase in the number of patients needed to treat with a prophylactic defibrillator to prevent one adverse event. The risk of an event may even be sufficiently low to limit the detectable benefit of defibrillators in patients with the prognostic features identified in our study. This argues for additional risk stratification prior to the prophylactic implantation of a defibrillator.

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We derive necessary and sufficient conditions under which a set of variables is informationally sufficient, i.e. it contains enough information to estimate the structural shocks with a VAR model. Based on such conditions, we suggest a procedure to test for informational sufficiency. Moreover, we show how to amend the VAR if informational sufficiency is rejected. We apply our procedure to a VAR including TFP, unemployment and per-capita hours worked. We find that the three variables are not informationally sufficient. When adding missing information, the effects of technology shocks change dramatically.

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It is established that the ratio between step length (SL) and step frequency (SF) is constant over a large range of walking speed. However, few data are available about the spontaneous variability of this ratio during unconstrained outdoor walking, in particular over a sufficient number of steps. The purpose of the present study was to assess the inter- and intra-subject variability of spatio-temporal gait characteristics [SL, SF and walk ratio (WR=SL/SF)] while walking at different freely selected speeds. Twelve healthy subjects walked three times along a 100-m athletic track at: (1). a slower than preferred speed, (2). preferred speed and (3). a faster than preferred speed. Two professional GPS receivers providing 3D positions assessed the walking speed and SF with high precision (less than 0.5% error). Intra-subject variability was calculated as the variation among eight consecutive 5-s samples. WR was found to be constant at preferred and fast speeds [0.41 (0.04) m.s and 0.41 (0.05) m.s respectively] but was higher at slow speeds [0.44 (0.05) m.s]. In other words, between slow and preferred speed, the speed increase was mediated more by a change in SF than SL. The intra-subject variability of WR was low under preferred [CV, coefficient of variation = 1.9 (0.6)%] and fast [CV=1.8 (0.5)%] speed conditions, but higher under low speed condition [CV=4.1 (1.5)%]. On the other hand, the inter-subject variability of WR was 11%, 10% and 12% at slow, preferred and fast walking speeds respectively. It is concluded that the GPS method is able to capture basic gait parameters over a short period of time (5 s). A specific gait pattern for slow walking was observed. Furthermore, it seems that the walking patterns in free-living conditions exhibit low intra-individual variability, but that there is substantial variability between subjects.

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Provides advice and guidance on obtaining reserved car parking where a member of staff has particular difficulty with normal parking arrangements because of their disability/long-term health condition. åÊAmended 2009

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Provides guidance and advice on notifying a disability/long-term health condition to PMB and on requesting a reasonable adjustment, if you have previously declared a disability/long-term health condition.

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Immunoglobulin (Ig) A represents the predominant antibody isotype produced at the intestinal mucosa, where it plays an important role in limiting the penetration of commensal intestinal bacteria and opportunistic pathogens. We show in mice that Peyer's Patch-derived dendritic cells (PP-DC) exhibit a specialized phenotype allowing the promotion of IgA production by B2 cells. This phenotype included increased expression of the retinaldehyde dehydrogenase 1 (RALDH1), inducible nitric oxide synthase (iNOS), B cell activating factor of the tumor necrosis family (BAFF), a proliferation-inducing ligand (APRIL), and receptors for the neuropeptide vasoactive intestinal peptide (VIP). The ability of PP-DC to promote anti-CD40 dependent IgA was partially dependent on retinoic acid (RA) and transforming growth factor (TGF)-beta, whilst BAFF and APRIL signaling were not required. Signals delivered by BAFF and APRIL were crucial for CD40 independent IgA production, although the contribution of B2 cells to this pathway was minimal. The unique ability of PP-DC to instruct naïve B cells to differentiate into IgA producing plasma cells was mainly imparted by the presence of intestinal commensal bacteria, and could be mimicked by the addition of LPS to the culture. These data indicate that exposure to pathogen-associated molecular patterns present on intestinal commensal bacteria condition DC to express a unique molecular footprint that in turn allows them to promote IgA production.

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The treatment and management of chronic conditions during adolescence pose specific issues that need to be appropriately handled by health professionals. In this paper, questions related to disclosure of the diagnosis, the management of adherence to therapy, the need for an interdisciplinary network approach, lifestyles' anticipatory guidance and prevention, and the transition into an adult healthcare setting are reviewed. Special areas such as the issue of life threatening diseases and the ethical aspects of the treatment of chronic conditions are also discussed.

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Alternative morphotypes can confer important selective advantages in different habitats, whereas they can be penalized in other circumstances. In ectotherms, such as reptiles, the body colour can have direct effects on numerous aspects of their existence, such as thermoregulation or prey-predator interactions. Darker melanic individuals show lower skin reflectance and consequently heat up more rapidly and maintain optimal body temperatures more easily than lighter coloured individuals. As a consequence, melanistic individuals of diurnal species in cool areas may exhibit higher body condition, growth rate, survival and fecundity than lighter coloured individuals. Such advantages of dark coloration may be counterbalanced by a lower crypsis to predators and a decreased foraging efficiency. We investigated, in two montane populations of asp vipers Vipera aspis, the relationship between (1) colour polymorphism and body condition and length and (2) the coloration of individuals and their elevational distribution. We showed significant relationships between (1) the coloration, body condition and sex of individuals; (2) sexes and reproductive state and morph frequency; and (3) colour morphs that were distributed following an elevational gradient. Hence, colour polymorphism plays an important role in the ecology and evolution of the asp viper and is maintained through differential selective pressures.

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In recent years, the fight against money laundering has emerged as a key issue of financial regulation. The Wolfsberg Group is an important multistakeholder agreement establishing corporate responsibility (CR) principles against money laundering in a domain where international coordination remains otherwise difficult. The fact that 10 out of the 25 top private banking institutions joined this initiative opens up an interesting puzzle concerning the conditions for the participation of key industry players in the Wolfsberg Group. The article presents a fuzzy-set analysis of seven hypotheses based on firm-level organizational factors, the macro-institutional context, and the regulatory framework. Results from the analysis of these 25 financial institutions show that public ownership of the bank and the existence of a code of conduct are necessary conditions for participation in the Wolfsberg Group, whereas factors related to the type of financial institution, combined with the existence of a black list, are sufficient for explaining participation.

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Arterial hypertension is a highly heterogeneous condition. It is therefore not surprising that blood pressure lowering agents acting via a given mechanism allow a normalization of blood pressure in a fraction of hypertensive subjects only. The combination of drugs with different mechanisms of action on the cardiovascular system results in a considerably higher antihypertensive efficacy, not only with regard to the absolute blood pressure reduction but also in the number of responders. This effect is not achieved at the expenses of tolerance, because usually lower doses of the combined agents are sufficient to achieve the target blood pressure. The administration of antihypertensive agents in fixed combination has the advantage of its simplicity for both the physician as well as the patient. This aspect also explains the increasing popularity of fixed combinations as a valuable option in the initial treatment of the hypertensive patient.