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61.
Detlef Stiller Birgit Gaschler-Markefski Frank Baumgart Frank Schindler Claus Tempelmann Hans-Jochen Heinze henning Scheich 《Magma (New York, N.Y.)》1997,5(4):275-284
Prosodic modulation of speech provides information about emotional states of speakers (affective prosodies) or serves as syntactic
markers to change linguistic aspects of speech (linguistic prosodies). Previous electrophysiological investigations and studies
on patients with right or left hemisphere damage showed nonuniform results with respect to lateralization of prosodic processing.
In this study 20 healthy right-handed volunteers were investigated with functional magnetic resonance imaging of the acoustically
responsive areas on the supratemporal plane while detecting phonemes as control targets or prosodies in strings of nonsense
syllables and adjectives, the latter randomly intonated in a declarative, interrogative, commanding, happy, or sad fashion.
In control task A the phoneme /a/ was detected in the syllables. In control task B the phoneme /a/ was detected in the adjectives,
and in the experimental task C the sad intonations (affective) and in the experimental task D the interrogative intonations
(linguistic) had to be detected in the same material. In task A intensity-weighted volumes of activated voxels were not different
in the two hemispheres (laterality index 0). In task B with an irrelevant phoneme detection with respect to prosodic material,
the population split into two subgroups with similar right or left hemispheric lateralization of activity leading to an absolute
laterality index of 26.8 across all subjects. During detection of affective prosodies (task C), lateralization was maintained
yet the absolute laterality index reduced to 14.5, while there was no lateralization during detection of linguistic prosodies.
The sum of activations in the two hemispheres was the same across all tasks and subgroups, which suggests that the lateralizations
occurring with presentation and detection of prosodic material depend on a redistribution of activity between hemispheres. 相似文献
62.
Systems of economic ratios are very important in the field of operative controlling. Functional equations of economic quantities may be analyzed by comparing actual current values of these variables with planned values or values of a previous period using methods of deviation analysis. In this paper different methods of deviation analysis are compared. They are based on conditions, which should be satisfied by methods used to determine the effects on a depending quantity caused by the change of its components. In some aspects these conditions are different from conditions for methods of deviation analysis used in cost accounting. Based on an approximation of the temporal change of economic quantities a new method of deviation analysis is developed. This concept satisfies all conditions formulated at the beginning of the paper. 相似文献
63.
Herschbach Peter; Duran Gabriele; Waadt Sabine; Zettler Angela; Amm Christoph; Marten-Mittag Birgit; Strian Friedrich 《Canadian Metallurgical Quarterly》1997,16(2):171
This study reports the psychometric properties of a 45-item diabetes-specific questionnaire, the Questionnaire on Stress in Patients with Diabetes—Revised (QSD-R), a modified and shortened version of the QSD (G. Duran et al; see record 1996-18805-001). The QSD-R was filled out by 1,930 individuals with insulin-dependent diabetes mellitus and noninsulin-dependent diabetes mellitus. Eight consistent scales were identified (values of Cronbach's α: .69–.81). The test-retest reliability for the total score after a 5-week interval was rtt?=?.63. The results provide evidence for the reliability and validity of this instrument. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
Griffin Joan M.; Greiner Birgit A.; Stansfeld Stephen A.; Marmot Michael 《Canadian Metallurgical Quarterly》2007,12(4):334
The demand/control/support and effort/reward imbalance models have relied on self-reported methods to describe how poor psychosocial working conditions lead to harmful health outcomes. The hindrance/utilization model uses an observational methodology to assess these relationships. Cross-sectional observational and self-reported data from 98 civil servants participating in the Whitehall II Study of British civil servants were used to test whether work conditions measured by each of the three theoretical models explained a significant amount of the variance in depression and anxiety symptoms. Observational measures were also used to assess potential common methods variance bias between the self-reported job conditions and the outcomes. Results showed that the demand/control/support model explained the most variance in depression and anxiety symptoms and the associations were not wholly due to common methods variance. Moreover, measures associated with job resources (e.g., skill discretion, social support and skill utilization) had a protective effect on depression and anxiety symptoms. Exertion-related conditions (e.g., demands, effort, over commitment) were not consistently associated with depression or anxiety symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
Previous experiments demonstrated an oviposition-deterring effect of larval frass in the Egyptian cotton leaf worm,Spodoptera littoralis (Boisd.). In this study, females were shown to perceive the oviposition-deterring substance(s) with their antennae. During dark, airtight, and cold (–10 °C) storage, the deterrent was persistent for at least 395 days. On the other hand, larval frass retained its activity for only two days when applied to cotton leaves. The deterrent activity of frass was independent of larval density. Frass of larvae reared at high densities deterred oviposition as well as frass of larvae feeding separately or in small groups. For significant oviposition deterrence, the minimum amount of frass was in the range of 5–10 mg frass per cotton leaf. An acetone extract of larval frass was highly deterrent, in contrast to extracts prepared with water, ethanol, chloroform, or pentane. 相似文献
66.
67.
Sub-micrometer particulate air pollution and cardiovascular mortality in Beijing, China 总被引:1,自引:0,他引:1
Breitner S Liu L Cyrys J Brüske I Franck U Schlink U Leitte AM Herbarth O Wiedensohler A Wehner B Hu M Pan XC Wichmann HE Peters A 《The Science of the total environment》2011,409(24):5196-5204
Background
While the link between particulate matter and cardiovascular mortality is well established, it is not fully investigated and understood which properties of the aerosol might be responsible for the health effects, especially in polluted mega-city areas.Objectives
Our goal was to explore the association between daily cardiovascular mortality and different particle metrics in the sub-micrometer range in Beijing, China.Methods
We obtained daily counts of cause-specific cardiovascular deaths in the Beijing urban area for the period March 2004 to August 2005. Concurrently, continuous measurements of particle number size distributions were performed. Particle number concentrations (NC) between 0.003 μm and 0.8 μm were converted to particle mass and surface area concentrations assuming spherical particles. Semi-parametric Poisson regression models adjusting for trend, seasonality, day of the week, and meteorology were used to estimate immediate, delayed and cumulative particle effects. Additionally, effect modification by air mass origin was investigated.Results
We observed associations between daily cardiovascular mortality and particle NC for a 2-days delay. Moreover, nearly all particle metrics showed 2-days delayed associations with ischemic heart disease mortality. The strongest association was found for particle NC in the size range 0.03-0.1 μm (7.1% increase in daily mortality with a 95%-confidence interval of 2.9%-11.5%, per an increase of 6250 particles/cm3). Results for surface and mass concentrations with a lag of two days indicated effect modification by air mass origin, whereas effects of particle NC were not modified.Conclusions
Results show an elevated risk of cardiovascular mortality in Beijing from short-term exposure to particulate air pollution in the sub-micrometer range. Results also indicate that locally produced smaller particles and regionally transported particles may exhibit different effects in Beijing. 相似文献68.
Image-guided, computer-assisted surgery systems require a common reference between the preoperative image data and the corresponding patient pathology. Therefore, the problem of an accurate and reliable 3-D patient registration and referencing has to be solved. Considering that during image data acquisition patient misalignment and movement can arise in three dimensions, an automatic image registration method must be based on a three-dimensional approach. The method presented in this paper provides accurate 3-D patient registration for correction of these movement errors during data acquisition and active patient referencing to update the position of the head during surgery. Experimental data concerning the accuracy of repeated positionings of our patient registration and reference system demonstrated a high degree of accuracy with mean spatial errors of 0.82 mm ± 0.31 mm in a plastic skull and 1.56 ± 0.76 mm in patients, respectively. Results suggest that non-invasive 3-D patient registration for image-guided surgery may be a precise and useful method for computer-assisted identification of anatomical structures. 相似文献
69.
70.
The new classification system for the reaction to fire performance of building products in Europe has been applied to five different product families of wood: Wood-based panels, Structural timber, Glued laminated timber, Solid wood panelling and cladding and Wood flooring as being ‘products with known and stable fire performance’. The European classification system includes two sub-systems, one main system for all construction products except floorings and the other for flooring products. Wood properties such as density, thickness, joints and types of end use application including different substrates have been studied thoroughly and are included in the classification. Most wood products fall in classes D-s2, d0 or Dfl-s1 (for floorings). Testing has been performed according to EN 13823 (2002) SBI- Single Burning Item test, EN ISO 9239-1 (2002) Radiant panel test, and EN ISO 11925-2 (2002) Small flame test. In all, more than one hundred wood products in different end use applications have been studied. Clear relationships between the main Euroclass fire performance parameters and product parameters (such as density and thickness) have been demonstrated. Tables with reaction to fire classification of different wood products and end use applications have been developed, approved by the European Commission and published in their Official Journal. This procedure is ongoing with further official decisions to be published. 相似文献