87 resultados para Haller, Johannes, 1523-1575.


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A new method for automated coronal loop tracking, in both spatial and temporal domains, is presented. Applying this technique to TRACE data, obtained using the 171 angstrom filter on 1998 July 14, we detect a coronal loop undergoing a 270 s kink-mode oscillation, as previously found by Aschwanden et al. However, we also detect flare-induced, and previously unnoticed, spatial periodicities on a scale of 3500 km, which occur along the coronal loop edge. Furthermore, we establish a reduction in oscillatory power for these spatial periodicities of 45% over a 222 s interval. We relate the reduction in detected oscillatory power to the physical damping of these loop-top oscillations.

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A World Conservation Union (IUCN) regional red list is an objective assessment of regional extinction risk and is not the same as a list of conservation priority species. Recent research reveals the widespread, but incorrect, assumption that IUCN Red List categories represent a hierarchical list of priorities for conservation action. We developed a simple eight-step priority-setting process and applied it to the conservation of bees in Ireland. Our model is based on the national red list but also considers the global significance of the national population; the conservation status at global, continental, and regional levels; key biological, economic, and societal factors; and is compatible with existing conservation agreements and legislation. Throughout Ireland, almost one-third of the bee fauna is threatened (30 of 100 species), but our methodology resulted in a reduced list of only 17 priority species. We did not use the priority species list to broadly categorize species to the conservation action required; instead, we indicated the individual action required for all threatened, near-threatened, and data-deficient species on the national red list based on the IUCN's conservation-actions template file. Priority species lists will strongly influence prioritization of conservation actions at national levels, but action should not be exclusive to listed species. In addition, all species on this list will not necessarily require immediate action. Our method is transparent, reproducible, and readily applicable to other taxa and regions.

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Solid-state NMR and TEM were used to quantitatively examine the evolution of clay morphology upon equibiaxial stretching of polypropylene/montmorillonite (PP-MMT) nanocomposites up to a stretch ratio (?= final length/initial length) of 3.5. 1 H spin-lattice relaxation times were measured by the saturation-recovery sequence. For the nanocomposites, initial portions of the magnetization recovery
curves (e~20 ms) were found to depend on v t, indicative of diffusion-limited relaxation and in agreement with calculations based on estimates of the spin-diffusion barrier radius surrounding the paramagnetic centers in the clay, the electron-nucleus coupling constant, and the spin-diffusion coefficient. Initial slopes of these magnetization recovery curves directly correlated with the fraction of clay/polymer interface. New clay surface was exposed as a near linear function of strain. Long-time portions of the magnetization recovery curves yielded information on the average interparticle separations, which decreased slowly before reaching a plateau at ?=~2.5 as particles aligned. TEM images supported these findings and were used to define and quantify degrees of exfoliation and homogeneity from the NMR data. Exfoliation, defined as (platelets/ stack)-1, increased from 0.38 (unstretched) to 0.80 at ? = 3.5 for PP-MMT nanocomposites stretched at
150 C and 16 s-1. A lower stretch temperature, 145 C, which is slightly below melting onset, led to an exfoliation degree of 0.87 at ?= 2.8, consistent with the ability of higher melt viscosities to allow for higher shear stress transfer. Exposure of new clay surface is attributed to aggregate breakup and orientation at low strains (? e ~2) and to platelets sliding apart at higher strains.

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Annotation of programs using embedded Domain-Specific Languages (embedded DSLs), such as the program annotation facility for the Java programming language, is a well-known practice in computer science. In this paper we argue for and propose a specialized approach for the usage of embedded Domain-Specific Modelling Languages (embedded DSMLs) in Model-Driven Engineering (MDE) processes that in particular supports automated many-step model transformation chains. It can happen that information defined at some point, using an embedded DSML, is not required in the next immediate transformation step, but in a later one. We propose a new approach of model annotation enabling flexible many-step transformation chains. The approach utilizes a combination of embedded DSMLs, trace models and a megamodel. We demonstrate our approach based on an example MDE process and an industrial case study.

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Some 10 years ago one of the authors embarked on a research study examining the potential for social workers to shift from a child protection to a child welfare practice orientation (Spratt, 2000; 2001; Spratt and Callan, 2004). The research reported here develops that work; examining how social workers respond to ‘child care problems’ (CCPs). The results indicate that Northern Irish Health and Social Services Trusts (equivalent to Local Authorities in England and Wales) have responded to social policy goals to balance the protection of a lesser number of children whilst meeting the welfare needs of the greater by reducing the number of referrals designated ‘child protection investigations’ (CPIs) and increasing the number of CCPs. Closer analysis reveals, however, that a filtering system has been developed by social workers to address perceived child protection risks within CCP cases. Paradoxically, this leads to early closure of the more concerning cases, with service provision largely confined to the least concerning. The authors argue that the ways in which social workers balance social policing and supportive functions in practice may indicate possible responses to an increase in referred families anticipated within Every Child Matters (Chief Secretary to the Treasury, 2003).

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The authors examined cue competition effects in young children using the blicket detector paradigm, in which objects are placed either singly or in pairs on a novel machine and children must judge which objects have the causal power to make the machine work. Cue competition effects were found in a 5- to 6-year-old group but not in a 4-year-old group. Equivalent levels of forward and backward blocking were found in the former group. Children's counterfactual judgments were subsequently examined by asking whether or not the machine would have gone off in the absence of I of 2 objects that had been placed on it as a pair. Cue competition effects were demonstrated only in 5- to 6-year-olds using this mode of assessing causal reasoning.

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NADH:ubiquinone oxidoreductase (complex I) is the largest and most complicated enzyme of aerobic electron transfer. The mechanism how it uses redox energy to pump protons across the bioenergetic membrane is still not understood. Here we determined the pumping stoichiometry of mitochondrial complex I from the strictly aerobic yeast Yarrowia lipolytica. With intact mitochondria, the measured value of 3.8H(->+)/2e(-) indicated that four protons are pumped per NADH oxidized. For purified complex I reconstituted into proteoliposomes we measured a very similar pumping stoichiometry of 3.6H(->+)/2e(-). This is the first demonstration that the proton pump of complex I stayed fully functional after purification of the enzyme. (c) 2006 Elsevier B.V. All rights reserved.

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Objectives: To investigate the impact of different PSA testing policies and health-care systems on prostate cancer incidence and mortality in two countries with similar populations, the Republic of Ireland (RoI) and Northern Ireland (NI).

Methods: Population-level data on PSA tests, prostate biopsies and prostate cancer cases 1993–2005 and prostate cancer deaths 1979–2006 were compiled. Annual percentage change (APC) was estimated by joinpoint regression.

Results: Prostate cancer rates were similar in both areas in 1994 but increased rapidly in RoI compared to NI. The PSA testing rate increased sharply in RoI (APC = +23.3%), and to a lesser degree in NI (APC = +9.7%) to reach 412 and 177 tests per 1,000 men in 2004, respectively. Prostatic biopsy rates rose in both countries, but were twofold higher in RoI. Cancer incidence rates rose significantly, mirroring biopsy trends, in both countries reaching 440 per 100,000 men in RoI in 2004 compared to 294 in NI. Median age at diagnosis was lower in RoI (71 years) compared to NI (73 years) (p < 0.01) and decreased significantly over time in both countries. Mortality rates declined from 1995 in both countries (APC = -1.5% in RoI, -1.3% in NI) at a time when PSA testing was not widespread.

Conclusions: Prostatic biopsy rates, rather than PSA testing per se, were the main driver of prostate cancer incidence. Because mortality decreases started before screening became widespread in RoI, and mortality remained low in NI, PSA testing is unlikely to be the explanation for declining mortality.

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Background: Fish intake, the major source of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), may reduce the risk of age-related macular degeneration (AMD). Objective: We investigated the association of oily fish and dietary DHA and EPA with neovascular AMD (NV-AMD). Design: Participants aged =65 y in the cross-sectional population-based EUREYE study underwent fundus photography and were interviewed by using a food-frequency questionnaire. Fundus images were graded by the International Classification System for Age Related Maculopathy. Questionnaire data were converted to nutrient intakes with the use of food-composition tables. Survey logistic regression was used to calculate odds ratios (ORs) and 95% CIs of energy-adjusted quartiles of EPA or DHA with NV-AMD, taking into account potential confounders. Results: Dietary intake data and fundus images were available for 105 cases with NV-AMD and for 2170 controls without any features of early or late AMD. Eating oily fish at least once per week compared with less than once per week was associated with a halving of the odds of NV-AMD (OR = 0.47; 95% CI: 0.33, 0.68; P = 0.002). Compared with the lowest quartile, there was a significant trend for decreased odds with increasing quartiles of either DHA or EPA. ORs in the highest quartiles were 0.32 (95% CI: 0.12, 0.87; P = 0.03) for DHA and 0.29 (95% CI: 0.11, 0.73; P = 0.02) for EPA. Conclusions: Eating oily fish at least once per week compared with less than once per week was associated with a halving of the OR for NV-AMD. © 2008 American Society for Nutrition.

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Comparative advertising by one brand against another showcases its merits versus the demerits of the other. In a two-stage game with finitely many firms, firms decide first how much to advertise against whom. In the second stage, given the advertising configuration, firms compete as Cournot oligopolists. In the symmetric case, equilibrium advertising constitutes a clear welfare loss. In the asymmetric case, depending on parameter values, a variety of outcomes are possible in equilibrium. An a priori disadvantaged firm (in terms of advertising costs or advertising effectiveness) may advertise more. Advertising can affect firms that are not advertisers or targets themselves.

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The incidence of allergy and asthma in developed countries is on the increase and this trend looks likely to continue. CD4(+) T helper 2 (Th2) cells are major drivers of these diseases and their commitment is controlled by cytokines such as interleukin 4, which are in turn regulated by the suppressor of cytokine signaling (SOCS) proteins. We report that SOCS2(-/-) CD4(+) T cells show markedly enhanced Th2 differentiation. SOCS2(-/-) mice, as well as RAG1(-/-) mice transferred with SOCS2(-/-) CD4(+) T cells, exhibit elevated type 2 responses after helminth antigen challenge. Moreover, in in vivo models of atopic dermatitis and allergen-induced airway inflammation, SOCS2(-/-) mice show significantly elevated IgE, eosinophilia, type 2 responses, and inflammatory pathology relative to wild-type mice. Finally, after T cell activation, markedly enhanced STAT6 and STAT5 phosphorylation is observed in SOCS2(-/-) T cells, whereas STAT3 phosphorylation is blunted. Thus, we provide the first evidence that SOCS2 plays an important role in regulating Th2 cell expansion and development of the type 2 allergic responses.