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991.
Willmott Lynn; Harris Peter; Gellaitry Grace; Cooper Vanessa; Horne Rob 《Canadian Metallurgical Quarterly》2011,30(5):642
Objective: To assess the effects of expressive writing on health care utilization, clinical variables and subjective quality of life following first myocardial infarction (MI). Methods: One-hundred and seventy-nine first MI patients were randomized to Intervention (N = 88) or Control (N = 91) groups. The intervention group wrote about their thoughts and feelings in relation to having had an MI. Controls wrote in a neutral way about daily activities. The main outcome measures were health care utilization, physical status and subjective quality of life (QOL), assessed after one, two, and five months. Results: One-hundred and fifty-six (87%) completed the study. Five months post-intervention, the intervention group had significantly fewer recorded medical appointments compared to controls. The number of prescribed medicines decreased over time within the intervention group but increased within the control group. The intervention group attended significantly more rehabilitation sessions, reported fewer cardiac related symptoms and had lower diastolic blood pressure five months post-intervention. There was no significant group by time interaction on reported physical health. The group by time interaction on reported mental health approached significance, those in the intervention group reporting greater improvement. Conclusion: Expressive writing may be a beneficial strategy which could be incorporated into rehabilitation interventions to help individuals adjust after first MI. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
992.
993.
Mechanical vibration of the grass and crop weighing lysimeters, located at the University of California West Side Field Research and Extension Station at Five Points, Calif. generated noise in lysimeter mass measurements and reduced the quality of evapotranspiration (ET) data. The estimated power spectral density (PSD) for grass lysimeter mass data acquired at 1.3?ms intervals contained a large peak at 11?Hz. Crop lysimeter data produced similar peaks at frequencies greater than 1?Hz. An effective method for eliminating this noise source is arithmetic averaging of the data, which should be acquired sufficiently rapidly to avoid aliasing. The PSD also increased with decreasing frequency in the range 1.0–0.1?Hz. This noise was addressed by Savitsky–Golay (SG) filtering using 7-, 11-, and 15-point filters. Each filter was applied to the same data set consisting of 2,560 measurements taken during a 1-min interval every 10?min over a 26.3-h period. Noise reduction factors, defined as the ratio of standard deviation of filtered lysimeter mass to standard deviation of unfiltered mean values of lysimeter mass for subsequences of the same data, were 0.90, 0.88, and 0.86 for the 7-, 11-, and 15-point filters, respectively. For the daytime data only, the factors were 0.88, 0.85, and 0.83. The SG filters were more effective during daytime when most of the lysimeter ET occurs. These methods are simple enough to be programmed into commercially available dataloggers for real time filtering. Hourly averages of the standard deviations of lysimeter mass measurements bear a distinct nonlinear relationship to hourly mean wind speed confirming earlier suppositions that wind loading causes noise in counterbalanced weighing lysimeters. 相似文献
994.
Investigations on metal-cutting machining processes that were conducted since the second half of the twentieth century have
considerably contributed to disclosing the principles underlying the cutting process. Although numerous studies have been
carried out on this subject, a generally valid model of the cutting process and the interactions in the separating processes
does not exist yet. Such a model could guarantee the disclosure of the principles of thermodynamic interactions between the
cutting process and the involved machine structure. This contribution is twofold and presents an experimental setup used to
determine cutting forces and temperatures in orthogonal cutting processes. The results are then used as a reference for simulations
made with the Discrete Element Method (DEM). The DEM is due to its meshless nature well suited to capture large deformations
and rupture of material which is included very naturally. It is examined to which extent the measured results can be captured
with the DEM model. 相似文献
995.
Andrea D Lehmann Fabian Blank Oliver Baum Peter Gehr Barbara M Rothen-Rutishauser 《Particle and fibre toxicology》2009,6(1):26
Background
Using an in vitro triple cell co-culture model consisting of human epithelial cells (16HBE14o-), monocyte-derived macrophages and dendritic cells, it was recently demonstrated that macrophages and dendritic cells create a transepithelial network between the epithelial cells to capture antigens without disrupting the epithelial tightness. The expression of the different tight junction proteins in macrophages and dendritic cells, and the formation of tight junction-like structures with epithelial cells has been demonstrated. Immunofluorescent methods combined with laser scanning microscopy and quantitative real-time polymerase chain reaction were used to investigate if exposure to diesel exhaust particles (DEP) (0.5, 5, 50, 125 μg/ml), for 24 h, can modulate the expression of the tight junction mRNA/protein of occludin, in all three cell types. 相似文献996.
Aiping Zeng Marcela M.M. Bilek David R. McKenzie Peter A. Lay 《Diamond and Related Materials》2009,18(10):1211-1217
The semiconductor capacitances of the nitrogen-doped amorphous carbon (a-C:N) materials with different sp3/sp2 C ratios were studied as a function of electrode potential in a-C:N/aqueous electrolyte systems. This dependence of capacitance on electrode potential in aqueous 0.1 M NaOH shows that the investigated a-C:N materials are intrinsic semiconductors. The space-charge layers inside the a-C:N electrodes behave similar to a Helmholtz layer because of the presence of surface states when the electrolytes contain O2 or anions other than OH−. The lower density and mobility of carriers of materials with a higher sp3 C fraction within the a-C:N material causes a suppression of redox reactions, and the lower density of carriers contributes to a lower capacitance. 相似文献
997.
998.
Peter Jacob 《Microsystem Technologies》2009,15(1):169-174
Even in latest technologies, poly-silicon-related failures are well-known as a reliability risk. Due to the fact, that polysilicon
reoxidizes in subsequent processing, physical failures frequently do not occur as time-zero functional failures. However,
the thin reoxidation can be cracked by voltage pulses during field application. This paper describes the most important mechanisms
like particles, stringers, trimming-fuse recombinations and polySi-extensions with respect to failure diagnosis, screening
and reliability aspects. 相似文献
999.
让我们聚焦于化工厂控制室内的一个操作人员。他(或者她)的眼睛注视着HMI屏幕,短暂停留在储罐液位显示。这些操作人员是否能够说出传感器的测量值是如何到达控制室的呢?答案很有可能是否定的,而且操作人员也并不关心这些事情。只要信息准确及时就可以,他们不在意信息是如何传递的。正是网络的透明性让整个工厂正常运作。 相似文献
1000.