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van der Ploeg Eleonore; Dorresteijn Sasja M.; Kleber Rolf J. 《Canadian Metallurgical Quarterly》2003,8(2):157
Workers in medium- or high-risk professions are often confronted with critical incidents at the workplace. The impact of these acute stressors may be serious and enduring. Many workers also experience chronic job stressors, such as work overload or role conflicts. This study examined the frequently neglected relationship of acute and chronic stressors with self-reported health symptoms, such as posttraumatic responses, fatigue, and burnout. This association was investigated in a sample of forensic doctors in the Netherlands (N = 84). It was found that the more traumatic events the respondents experienced, the more problems they reported in coping with the traumatic events. Chronic job stressors were associated with posttraumatic responses (intrusions and avoidances) and with burnout and fatigue. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Rinkenauer Gerhard; Osman Allen; Ulrich Rolf; Müller-Gethmann Hiltraut; Mattes Stefan 《Canadian Metallurgical Quarterly》2004,133(2):261
Lateralized readiness potentials (LRPs) were used to determine the stage(s) of reaction time (RT) responsible for speed-accuracy trade-offs (SATs). Speeded decisions based on several types of information were examined in 3 experiments, involving, respectively, a line discrimination task, lexical decisions, and an Erikson flanker task. Three levels of SAT were obtained in each experiment by adjusting response deadlines with an adaptive tracking algorithm. Speed stress affected the duration of RT stages both before and after the start of the LRP in all experiments. The latter effect cannot be explained by guessing strategies, by variations in response force, or as an indirect consequence of the pre-LRP effect. Contrary to most models, it suggests that SAT can occur at a late postdecisional stage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Palmitoyl-CoA hydrolase [EC 3.1.2.2.] activity in rat liver was found to be enhanced by high fat diets. Partially hydrogenated
marine oil and high-erucic acid rapeseed oil diets produced a greater increase than a diet containing soybean oil.
With diets containing from 5 to 30% (w/w) of partially hydrogenated marine oil the increase in palmitoyl-CoA hydrolase activity
was similar to the increase observed in peroxisomal β-oxidation activity (correlation coefficient r=0.94). A positive correlation
(r=0.86) also was observed between the activity of palmitoyl-CoA hydrolase and previously determined levels of long-chain
acyl-CoA.
The results presented may suggest a common “induction” mechanism for palmitoyl-CoA hydrolase and peroxisomal β-oxidation enzymes,
possibly exerted through an increased cellular level of long-chain acyl-CoA. 相似文献
17.
Huihua Liu Eva Bracht Xin‐an Zhang Bret Bradley Rolf van Dick 《Creativity & Innovation Management》2021,30(1):129-143
An increasing number of individuals work in jobs with little standardization and repetition, that is, with high levels of job non‐routinization. At the same time, demands for creativity are high, which raises the question of how employees can use job non‐routinization to develop creativity. Acknowledging the importance of social processes for creativity, we propose that transformational leaders raise feelings of organizational identification in followers and that this form of identification then helps individuals to develop creativity in jobs with little routinization. This is because organizational members evaluate and promote those ideas as more creative, which are in line with a shared understanding of creativity within the organization. To investigate these relationships, we calculated a mediated moderation model with 173 leader–follower dyads from China. Results confirm our hypotheses that transformational leadership moderates the relationship between job non‐routinization on employee creativity through organizational identification. We conclude that raising feelings of social identity is a key task for leaders today, especially when working in uncertain and fast developing environments with little repetition and the constant need to develop creative ideas. 相似文献
18.
We present a multimodal document alignment framework, which highlights existing alignment relationships between documents that are discussed and recorded during multimedia events such as meetings. These relationships that should help indexing the archives of these events are detected using various techniques from natural language processing and information retrieval. The main alignment strategies studied are based on thematic, quotation and reference relationships. At the analysis level, the alignment framework was applied at several levels of granularity of documents, requiring specific document segmentation techniques. Our framework that is language independent was evaluated on corpora in French and English, including meetings and scientific presentations. The satisfactory evaluation results obtained at several stages show the importance of our approach in bridging the gap between meeting documents, independently from the language and domain. They highlight also the utility of the multimodal alignment in advanced applications, e.g. multimedia document browsing, content-based / temporal-based searching, etc. 相似文献
19.
Rolf Hardt Werner Baltes 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,185(4):275-280
Summary After an introduction on the production, classification, legislative regulations, toxicology, and analysis of caramel colours, a report is given on the examination of these colourings by Curie-point pyrolysis-capillary gas chromatography-mass spectrometry. This method enables the differentiation between the four classes of caramel colours on the basis of the most concentrated of more than 100 identified pyrolysis products, which requires small quantities of substance (100 g) and short periods of time (1 h).
Zur Analytik von Zuckercouleuren I. Mitteilung: Differenzierung der Couleurklassen mittels Curiepunkt-Pyrolyse-Capillargaschromatographie-Massenspektrometrie
Zusammenfassung Nach einer Einführung zur Herstellung, Klassifizierung, rechtlichen Stellung, Toxikologie und Analytik der Zuckercouleure wird über die Untersuchung dieser Farbstoffe mittels Curiepunkt-Pyrolyse-Capillargaschromatographie-Massenspektrometrie berichtet. Anhand der konzentrationsstärksten der über 100 identifizierten Pyrolyseprodukte ist es möglich, die vier Couleurklassen bei geringem Substanz- (100 g) and Zeitbedarf (1 h) sicher zu differenzieren.相似文献
20.
Multiple inhibitory effects of garlic extracts on cholesterol biosynthesis in hepatocytes 总被引:2,自引:0,他引:2
Rolf Gebhardt 《Lipids》1993,28(7):613-619
Exposure of primary rat hepatocytes and human HepG2 cells to water-soluble garlic extracts resulted in the concentration-dependent
inhibition of cholesterol biosynthesis at several different enzymatic steps. At low concentrations, sterol biosynthesis from
[14C]acetate was decreased in rat hepatocytes by 23% with an IC50 (half-maximal inhibition) value of 90μg/mL and in HepG2 cells by 28% with an IC50 value of 35 μg/mL. This inhibition was exerted at the level of hydroxymethylglutaryl-COA reductase (MHG-CoA reductase) as
indicated by direct enzymatic measurements and the absence of inhibition if [14C]mevalonate was used as a precursor. At high concentrations (above 0.5 mg/mL), inhibition of cholesterol biosynthesis was
not only seen at an early step where it increased considerably with dose, but also at later steps resulting in the accumulation
of the precursors lanosterol and 7-dehydrocholesterol. No desmosterol was formed which, however, was a major precursor accumulating
in the presence of triparanol. Thus, the accumulation of sterol precursors seem to be of less therapeutic significance during
consumption of garlic, because it requires concentrations one or two orders of magnitude above those affecting HMG-CoA reductase.
Alliin, the main sulfur-containing compound of garlic, was without effect itself. If converted to allicin, it resulted in
similar changes of the sterol pattern. This suggested that the latter compound might contribute to the inhibition at the late
steps. In contrast, nicotinic acid and particularly adenosine caused moderate inhibition of HMG-CoA reductase activity and
of cholesterol biosynthesis suggesting that these compounds participate, at least in part, in the early inhibition of sterol
synthesis by garlic extracts.
Dedication: This article is dedicated to Prof. Dr. D. Mecke on the occasion of his 60th birthday. 相似文献