944 resultados para Charm in matter
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Background: Semantic memory processes have been well described in literature. However, the available findings are mostly based on relatively young subjects and concrete word material (e.g. tree). Comparatively little information exists about semantic memory for abstract words (e.g. mind) and possible age related changes in semantic retrieval. In this respect, we developed a paradigm that is useful to investigate the implicit (i.e. attentionindependent) access to concrete and abstract semantic memory. These processes were then compared between young and elderly healthy subjects. Methods: A well established tool for investigating semantic memory processes is the semantic priming paradigm, which consists both of semantically unrelated and related word pairs. In our behavioral task these noun-noun word pairs were further divided into concrete, abstract and matched pronounceable non-word conditions. With this premise, the young and elderly participants performed a lexical decision task: they were asked to press a choice of two buttons as an indication for whether the word pair contained a non-word or not. In order to minimize controlled (i.e. attention-dependent) retrieval strategies, a short stimulus onset asynchrony (SOA) of 150ms was set. Reaction time (RT) changes and accuracy to related and unrelated words (priming effect) in the abstract vs. concrete condition (concreteness effect) were the dependent variables of interest. Results and Discussion: Statistical analysis confirmed both a significant priming effect (i.e. shorter RTs in semantically related compared to unrelated words) and a concreteness effect (i.e. RT decrease for concrete compared to abstract words) in the young and elderly subjects. There was no age difference in accuracy. The only age effect was a commonly known general slowing in RT over all conditions. In conclusion, age is not a critical factor in the implicit access to abstract and concrete semantic memory.
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In this article we calculate the one-loop supersymmetric QCD (SQCD) corrections to the decay u˜1→cχ˜01 in the minimal supersymmetric standard model with generic flavor structure. This decay mode is phenomenologically important if the mass difference between the lightest squark u˜1 (which is assumed to be mainly stoplike) and the neutralino lightest supersymmetric particle χ˜01 is smaller than the top mass. In such a scenario u˜1→tχ˜01 is kinematically not allowed and searches for u˜1→Wbχ˜01 and u˜1→cχ˜01 are performed. A large decay rate for u˜1→cχ˜01 can weaken the LHC bounds from u˜1→Wbχ01 which are usually obtained under the assumption Br[u˜1→Wbχ01]=100%. We find the SQCD corrections enhance Γ[u˜1→cχ˜01] by approximately 10% if the flavor violation originates from bilinear terms. If flavor violation originates from trilinear terms, the effect can be ±50% or more, depending on the sign of At. We note that connecting a theory of supersymmetry breaking to LHC observables, the shift from the DR¯¯¯¯¯ to the on-shell mass is numerically very important for light stop decays.
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Introduction: Current demographic changes are characterized by population aging, such that the surgical treatment of degenerative spine conditions in the elderly is gaining increasing relevance. However, there is a general reluctance to consider spinal fusion procedures in this patient age group due to the increased likelihood of complications. The aim of this study was to assess the patient-rated outcome and complication rates associated with lumbar fusion procedures in three different age groups. Methods: This was a retrospective analysis of prospectively collected data from consecutive patients who underwent first-time, one to three level posterior instrumented fusion between 2004 and 2011, due to degenerative disease of the lumbar spine. Data were obtained from our Spine Surgery Outcomes Database (linked to the International Spine Tango Register). Before surgery, patients completed the multidimensional Core Outcome Measures Index (COMI), and at 3 and 12 months after surgery they completed the COMI and rated the Global Treatment Outcome (GTO) and their satisfaction with care. Patients were divided into three groups according to their age: younger (≥50y <65y; n = 317), older (≥65y <80y; n = 350), and geriatric (≥ 80y; n = 40). Results: 707 consecutive patients were included. The preoperative comorbidity status differed significantly (p < 0.0001) between the age groups, with the highest scores in the geriatric group. General medical complications during surgery were lower in the younger age group (7%) than in the older (13.4%; p = 0.006) and geriatric groups (17.5%; p = 0.007). Duration of hospital stay was longer (p = 0.006) in the older group (10.8 ± 3.7 days) than the younger (10.0 ± 3.6 days) group. There were no significant group differences (p>0.05) for any of the COMI domains covering pain, function, symptom specific well-being, general quality of life, and social and work disability at either 3 months’ or 12 months’ follow-up. Similarly, there were no differences (p>0.05) between the age groups for GTO and patient-rated satisfaction at either follow-up. Conclusions: Preoperative comorbidity and general medical complications during lumbar fusion for degenerative disorders of the lumbar spine are both greater in geriatric patients than in younger patients. However, patient-rated outcome is as good in the elderly as it is in younger age groups. These data suggest that geriatric age per se is not a contraindication to instrumented fusion for lumbar degenerative disease.
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Einleitung Folgt man den aktuellen Sportentwicklungsberichten, dann sehen sich zunehmend mehr Sportvereine mit Mitgliederfluktuationen sowie stagnierenden bzw. zurückgehenden Mitglie- derzahlen konfrontiert (Lamprecht et al. 2012). Jedoch werden nicht alle Vereine in gleichem Maße mit instabilen Mitgliedschaftsverhältnissen konfrontiert. So gibt es mit Blick auf die Mitgliederstruktur Vereine, die – aufgrund ihrer spezifischen situativen und strukturellen Bedingungen – kaum Probleme mit Mitgliederfluktuation und Vereinsaustritten haben, wohin- gegen andere Vereine mitunter erhebliche Mitgliederrückgänge verzeichnen. Demnach ist zu vermuten, dass sich das soziale Handeln der Vereinsmitglieder je nach Organisationsprofil der Vereine unterscheidet. Zwar werden Verknüpfungen von Individual- und korrespondierenden Strukturdaten innerhalb der Sportvereinsforschung bereits seit geraumer Zeit gefordert (z.B. Nagel, 2007), aber bis heute nicht konsequent umgesetzt. Es stellt sich deshalb die Frage, welche organisations- und individuumsbezogenen Faktoren für die Mitgliederbindung in Sportvereinen eine Rolle spielen? Theoretisch-methodisches Vorgehen Im Zusammenhang mit der Frage der Mitgliederbindung wird davon ausgegangen, dass kontextuelle Bedingungen individuelle Entscheidungen strukturieren und somit persönliche Handlungsketten beeinflussen können (Coleman, 1990). Auf dieser Grundlage wird ein Mehr- ebenenmodell entwickelt, das neben individuellen Merkmalen auch die Strukturbedingungen von Sportvereinen berücksichtigt, die im Zusammenhang mit der individuellen Wahlhandlung zwischen stabiler Mitgliedschaft oder Austritt stehen. Der organisationale Kontext Sportverein wird dabei als Interessenorganisation konzeptualisiert, der mit seinen Kontexteigenschaften als Gelegenheits- und Opportunitätsstruktur, als kultureller sowie sozialer Bezugsrahmen gewisse Anreize schafft („Logik der Situation“), die gemäss individueller Präferenzen („Logik der Selektion“) zu Parametern des Mitgliederhandelns werden können. Die aus dem Modell abgeleiteten Annahmen werden auf der Grundlage einer Mitglieder- befragung (n = 1.434) in 36 Schweizer Sportvereinen empirisch geprüft. Die adäquate Methode, welche die hierarchische Datenstruktur (jede Messung auf der Individualebene kann eindeutig einer Messung auf der Vereinsebene zugeordnet werden) adäquat berücksichtigt und folglich das entwickelte theoretische Modell statistisch umsetzt, ist die Mehrebenenanalyse (z.B. Hox, 2002). Entsprechend wird der Einfluss der Individual- und Kontextebene auf die Mitglieder- bindung in Sportvereinen anhand unterschiedlicher Mehrebenenmodelle (Random Intercept, Random Slope sowie Cross-Level Interaktionen) geschätzt. Ergebnisse Die Analysen machen deutlich, dass sich die dauerhafte Mitgliedschaft in Sportvereinen nicht allein auf individuelle Merkmale der Mitgliedschaft, wie eine ausgeprägte Verbundenheit, ein positiv wahrgenommenes soziales Miteinander, die Zufriedenheit mit der Vereinsarbeit sowie die ehrenamtliche Mitarbeit zurückführen lässt. Darüber hinaus nehmen auch vereinsspezi-fische Strukturbedingungen Einfluss auf die Mitgliederbindung, wobei in ländlich geprägten Sportvereinen und in Vereinen, die Geselligkeit explizit fordern und in denen das Vereinsziel sportlicher Erfolg eher eine untergeordnete Rolle spielt, die Austrittswahrscheinlichkeit geringer ist. Diskussion Die Befunde machen deutlich, dass für eine dauerhafte Mitgliedschaft sowohl zweckorientierte Nutzenüberlegungen als auch solidargemeinschaftliche Handlungsorientierungen eine zentrale Rolle spielen, so dass eine ausschließliche Dienstleistungs- bzw. Kundenorientierung als Strategie der Mitgliederbindung in Sportvereinen, wie sie vielfach (auch von Verbänden) nahegelegt wird, zu kurz greifen dürfte. Weiterhin zeigt sich, dass der Sportverein als Ort der Geselligkeit nicht nur Werte des sozialen Miteinanders und solidarischen Verhaltens vermittelt, sondern auch als Katalysator der Stabilität der Mitgliedschaft wirkt, sofern entsprechende Gelegenheiten zur Verfügung stehen. Im Zusammenhang mit der Mitgliederbindung scheint damit gerade jene vereinskulturelle Orientierung von Vereinen bedeutsam, die im Zuge der Modernisierung von Vereinsangeboten gern als überholt erachtet wird. Literatur Coleman, J. S. (1990). Foundations of social theory. Cambridge, MA: Belknap. Hox, J. (2002). Multilevel analysis. Techniques and applications. Mahwah: Erlbaum. Lamprecht, M., Fischer, A. & Stamm, H.-P. (2012). Die Schweizer Sportvereine – Strukturen, Leistungen, Herausforderungen. Zürich: Seismo. Nagel, S. (2007). Akteurtheoretische Analyse der Sportvereinsentwicklung – ein theoretisch- methodischer Bezugsrahmen. Sportwissenschaft, 37, 186–201.
Does context matter? Analysing structural and individual factors of member commitment in sport clubs
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This article addresses factors that infl uence member commitment in sport clubs. Based on the theory of social action and the economic behaviour theory, it focuses not only on individual characteristics of club members but also on the corresponding structural conditions of sport clubs. Accordingly, a multilevel framework is developed for explaining member commitment in sport clubs. Different multilevel models were estimated in order to analyse the infl uences of both the individual and corresponding context Level in a sample of n = 1,699 members of 42 Swiss and German sport clubs. The multilevel analysis permitted an adequate handling of hierarchically structured data. Results of These multilevel analyses indicated that the commitment of members is not just an outcome of individual characteristics such as strong identifi cation with their club, positively perceived (collective) solidarity, satisfaction with their sport club, or voluntary engagement. It is also determined by club-specific structural conditions: commitment proves to be more probable in rural sport clubs and clubs that explicitly support sociability. Furthermore, cross-level effects in relation to member commitment were also found between the context variable sociability and the individual variable identification.
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Results of a search for supersymmetry via direct production of third-generation squarks are reported, using 20.3 fb −1 of proton-proton collision data at √s =8 TeV recorded by the ATLAS experiment at the LHC in 2012. Two different analysis strategies based on monojetlike and c -tagged event selections are carried out to optimize the sensitivity for direct top squark-pair production in the decay channel to a charm quark and the lightest neutralino (t 1 →c+χ ˜ 0 1 ) across the top squark–neutralino mass parameter space. No excess above the Standard Model background expectation is observed. The results are interpreted in the context of direct pair production of top squarks and presented in terms of exclusion limits in the m ˜t 1, m ˜ X0 1 ) parameter space. A top squark of mass up to about 240 GeV is excluded at 95% confidence level for arbitrary neutralino masses, within the kinematic boundaries. Top squark masses up to 270 GeV are excluded for a neutralino mass of 200 GeV. In a scenario where the top squark and the lightest neutralino are nearly degenerate in mass, top squark masses up to 260 GeV are excluded. The results from the monojetlike analysis are also interpreted in terms of compressed scenarios for top squark-pair production in the decay channel t ˜ 1 →b+ff ′ +χ ˜ 0 1 and sbottom pair production with b ˜ 1 →b+χ ˜ 0 1 , leading to a similar exclusion for nearly mass-degenerate third-generation squarks and the lightest neutralino. The results in this paper significantly extend previous results at colliders.
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search is presented for production of dark-matter particles recoiling against a leptonically decaying Z boson in 20.3 fb−1 of pp collisions at √s=8 TeV with the ATLAS detector at the Large Hadron Collider. Events with large missing transverse momentum and two oppositely charged electrons or muons consistent with the decay of a Z boson are analyzed. No excess above the Standard Model prediction is observed. Limits are set on the mass scale of the contact interaction as a function of the dark-matter particle mass using an effective field theory description of the interaction of dark matter with quarks or with Z bosons. Limits are also set on the coupling and mediator mass of a model in which the interaction is mediated by a scalar particle.