994 resultados para market situation
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Questionnaire studies indicate that high-anxious musicians may suffer from hyperventilation symptoms before and/or during performance. Reported symptoms include amongst others shortness of breath, fast or deep breathing, dizziness and thumping heart. A self-report study by Widmer, Conway, Cohen and Davies (1997) shows that up to seventy percent of the tested highly anxious musicians are hyperventilators during performance. However, no study has yet tested if these self-reported symptoms reflect actual cardiorespiratory changes just before and during performance. Disturbances in breathing patterns and hyperventilation may negatively affect the performance quality in stressful performance situations. The main goal of this study is to determine if music performance anxiety is manifest physiologically in specific correlates of cardiorespiratory activity. We studied 74 professional music students of Swiss Music Universities divided into two groups (high- and lowanxious) based on their self-reported performance anxiety (State-Trait Anxiety Inventory by Spielberger). The students were tested in three distinct situations: baseline, performance without audience, performance with audience. We measured a) breathing patterns, end-tidal carbon dioxide, which is a good non-invasive estimator for hyperventilation, and cardiac activation and b) self-perceived emotions and self-perceived physiological activation. Analyses of heart rate, respiratory rate, self-perceived palpitations, self-perceived shortness of breath and self-perceived anxiety for the 15 most and the 15 least anxious musicians show that high-anxious and low-anxious music students have a comparable physiological activation during the different measurement periods. However, highanxious music students feel significantly more anxious and perceive significantly stronger palpitations and significantly stronger shortness of breath just before and during a public performance. The results indicate that low- and high-anxious music students a) do not differ in the considered physiological responses and b) differ in the considered self-perceived physiological symptoms and the selfreported anxiety before and/or during a public performance.
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Using reaggregating rat brain cell cultures at two different stages of differentiation, we examined the biochemical effects of a 10-day treatment with nanomolar concentrations of methylmercuric chloride (monomethylmercury), in the presence or absence of promoters of hydroxyl radical formation (10 microM copper sulphate plus 100 microM ascorbate). A decrease in total protein content accounted for the general cytotoxicity of these compounds, whereas selective effects were assessed by determining the activities of cell type-specific enzymes. Methylmercury, up to 100 nM, as well as the copper ascorbate mixture, when applied separately, induced no general cytotoxicity, and only slight effects on neuronal parameters. However, when applying 100 nM methylmercury and the copper-ascorbate mixture together, a drastic decrease in neuronal and glial parameters was found. Under these conditions, the content of reactive oxygen species, assessed by 2',7'-dichlorofluorescin oxidation, increased greatly, while the activities of antioxidant enzymes decreased. In the presence of copper and ascorbate, differentiated cultures appeared more resistant than immature ones to low methylmercury concentrations (1-10 mM), but did undergo similar changes in both cell type-specific and antioxidant enzyme activities at 100 nM methylmercury. These results suggest that in prooxidant conditions low doses of mercury can become much more deleterious for the central nervous system.
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Fragebogenstudien haben gezeigt, dass ängstliche Musiker vor und/oder während eines Auftritts möglicherweise unter Hyperventilationssymptomen leiden. Berichtete Symptome beinhalten Kurzatmigkeit, schnelles oder tiefes Einatmen, Schwindelgefühl und Herzklopfen. Bisher hat jedoch noch keine Studie getestet, ob diese selbstberichteten Symptome tatsächlich kardiorespiratorische Veränderungen widerspiegeln. Das Hauptziel dieser Studie ist es, zu bestimmen, ob sich Auftrittsangst bei Musikern physiologisch über kardiorespiratorische Muster äußert. Wir haben insgesamt 74 Musikstudenten von Schweizer Musikhochschulen getestet. Diese Studenten wurden aufgrund ihrer selbstberichteten Auftrittsangst (STAI-S) in zwei Gruppen unterteilt: ängstliche Musiker und nichtängstliche Musiker. Die Studenten wurden in drei unterschiedlichen Situationen getestet: Ausgangszustand, Auftritt ohne Publikum, Auftritt mit Publikum. Wir haben folgende Parameter gemessen: a) kardiorespiratorische Muster und endexpiratorisches CO2, welches eine gute nichtinvasive Schätzung des Hyperventilationsgrades liefert und b) subjektiv wahrgenommene Emotionen und subjektiv wahrgenommene physiologische Aktivität. Das Poster zeigt die ersten Resultate der 15 ängstlichsten und der 15 am wenigsten ängstlichen Musiker. Das Hauptinteresse gilt den folgenden Punkten: Herz- und Atemfrequenz, subjektiv wahrgenommenes Herzklopfen, subjektiv wahrgenommene Kurzatmigkeit und subjektiv wahrgenommenes Angstgefühl. Die Resultate dieser Studie zeigen erstens, dass ängstliche und nichtängstliche Musikstudenten zu den verschiedenen Messzeitpunkten eine vergleichbare physiologische Aktivität aufweisen und zweitens, dass ängstliche Musikstudenten ein signifikant höheres Angstgefühl haben und signifikant mehr Herzklopfen und Kurzatmigkeit wahrnehmen vor und/oder während eines Auftritts mit Publikum. Dies deutet darauf hin, dass sich ängstliche und nichtängstliche Musikstudenten a) bezüglich der subjektiv wahrgenommenen physiologischen Symptome und des selbst berichteten Angstgefühls vor und/oder während eines öffentlichen Auftritts unterscheiden und sich b) bezüglich der untersuchten physiologischen Reaktionen nicht unterscheiden.
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In recent years, several screening tests for subclinical atherosclerosis have been developed. The aim of these tests is to be able to better target preventive therapies to patients at high cardiovascular risk. However, the validity of these screening tests has not been well established for wide use in clinical practice. Being aware of these tests results might also enhance patient motivation to change unhealthy behaviors, such as smoking. However, the effectiveness of such strategy has been poorly studied. Early therapy of atherosclerosis has not been shown to improve clinical outcomes yet. Moreover, potential harms of such screening, such as induced anxiety, have been poorly studied. Although promising, such screening should be validated by clinical trials before routine use in clinical practice.
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Abstract
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Selostus: Tuki- ja hintamuutosten vaikutus maitotilojen pellon käyttöön
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Selostus: Suomen ruokaperunamarkkinoiden toimivuus