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991.
992.
This study investigated the relationship of depressive symptoms, social support, and a range of personal health behaviors in 2,091 male and 3,438 female university students from 16 countries. Depressive symptoms and social support were measured using the short Beck Depression Inventory and the Social Support Questionnaire; 9 personal health behaviors were also assessed. After the authors took age, social support, and clustering by country into account, depressive symptoms were significantly associated with lack of physical activity, not eating breakfast, irregular sleep hours, and not using a seat belt in both men and women, and additionally with smoking, not eating fruit, and not using sunscreen among women. Low social support was independently associated with low alcohol consumption, lack of physical activity, irregular sleep hours, and not using a seat belt in men and women. Bidirectional causal pathways are likely to link health behaviors with depressed mood. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
David G. Stevenson Fred J. Eller Milica Radosavljevi Jay-lin Jane & George E. Inglett 《International Journal of Food Science & Technology》2007,42(12):1489-1496
Morphology, starch structures and thermal and pasting properties of oat bran concentrate (OBC) and Nutrim‐OB (NOB), a jet‐cooked oat bran product, with or without supercritical carbon dioxide extraction (SCD) were studied. Oil composition was analysed. OBC had three thermal transitions, starch gelatinisation and two amylose–lipid complex transitions. NOB only had amorphous amylose–lipid transition. SCD significantly decreased gelatinisation temperatures of OBC. Pasting properties, showed NOB had significantly higher peak viscosity and breakdown, with significantly lower final viscosity, setback and pasting temperature compared with OBC. SCD increased peak viscosity for NOB and final viscosity for OBC. Thermogravimetric analysis showed NOB had higher water‐holding capacity (WHC) than OBC, while SCD decreased WHC. Amylopectin molecular weight was 3.4 × 108 for OBC and was significantly lower for NOB (1.4 × 108). Predominant fatty acids were oleic (41%), linoleic (38%) and palmitic (16%). Study showed NOB had different properties from OBC thereby expanding industrial applications. 相似文献
994.
Jens Hetland Hanne Marie Kvamsdal Geir Haugen Fredrik Major Vemund Kårstad Göran Tjellander 《Applied Energy》2009
Sevan Marine and Siemens have developed a floating power plant – entitled Sevan GTW (gas-to-wire) – based on Sevan’s cylindrical platform and Siemens’ SCC-800 combined cycle, and SINTEF has adapted a post-combustion CO2 capture process for on board integration including compression and preconditioning of the CO2. Main emphasis has been placed on developing an optimised conceptual design within the structural constraints, and assessing how efficient the capture unit may be operated in consideration of the dynamic behaviour induced by the sea on the absorber and desorber columns via the floating carrier. The rational behind this technology selection is the urgency in making appropriate steps for a quick start for remote power generation at sea with the inclusion of CCS to serve offshore oil and gas operations. This calls for modular power blocks made up by high efficient combined power cycles with post-combustion exhaust gas cleaning. From this point of view a system with four absorption columns and one desorber unit has been determined based on structured packing material. The capture process has been integrated with the power cycle in due consideration of the sea forces. It is shown that a permanent tilt becomes more important than periodic movements provided the harmonic periods are kept within a certain level (<20 s). Operational conditions and constraints vis-à-vis movements and trimming of the floater have been addressed and discussed with reference to available literature. This also includes the liquid hold-up and gas–liquid interfacial area in the absorption columns linked with tilting. Optimisation reveals that a reboiler duty of 3.77 GJ/ton CO2 would result in the lowest capture cost. With a energy penalty of 9%-points the Sevan GTW concept presents itself as a realistic concept deemed to be within reach today. 相似文献
995.
Abstract— A series of 12 display frames of different combinations of gloss levels and diffuse reflectance levels was mounted on a display to test the visual comfort of 31 test subjects. The frames were tested in a controlled environment where a light reflex was purposefully visible on the frame. The intensity of the light reflex was controllable by the user, and the dial setting was recorded for each frame. The frames were also shown in two different test office environments, one light and one dark. Qualitative comments about the frames were recorded. A gloss level of 30 gloss units corresponded to about 30% of test subjects that wanted no reflex at all to be visible on the frame. There was a significant effect of frame gloss on the acceptable light level of the reflex. When the acceptable‐light‐level dial setting was converted to luminance contrast, the acceptable luminance contrast on the frames decreased with increasing gloss, and this effect was more pronounced for black frames. 相似文献
996.
Van Tubbergen Marie; Warschausky Seth; Birnholz Justin; Baker Sarah 《Canadian Metallurgical Quarterly》2008,53(1):93
Objective: To present a model of progressive skills involved in the development of expressing choice among children with significant speech and motor impairments. Problem: Choice making has often been defined and assessed as the expression of personal preference. Yet, for children with a combination of motor, speech, and possible cognitive impairments, communicating even basic knowledge often involves making a choice from predetermined options. Model: When planning and implementing educational goals, it is therefore critical to accurately assess choice-making abilities across the spectrum of domains, including choice making to express knowledge and skills. To date, few objective, systematic approaches to conceptualization and assessment of choice-making abilities exist. The authors describe a progression of skills involved in choice making and a framework for understanding the abilities that constitute the foundation for these skills and behaviors. Conclusion: There is evidence that the assessment of choice-making skills is a fundamental component in adapted cognitive assessments for children with significant motor and communicative impairments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Jakob Christensen Anne Marie Ladefoged Lars Nrgaard 《Journal of the Institute of Brewing》2005,111(1):3-10
Two fluorescence spectroscopic methods with the aim to develop a fast quantitative determination of bitterness in beer were tested. The first method was based on autofluorescence of the diluted and degassed beer samples without any further processing. A total of 21 dark and light beer samples were analyzed and multivariate Partial Least Squares (PLS) regression models to bitterness in form of international bitter units (IBU) were performed. A prediction error in the form of Root Mean Square Error of Cross‐Validation (RMSECV) of 2.77 IBU was obtained using six PLS components. Focusing only on the light beer samples the RMSECV was reduced to 1.81 IBU. The second method developed was based on addition of europium to induce delayed fluorescence signals in the beer samples. PLS models yielded an RMSECV of 2.65 IBU for all beers, while a model on the light beer samples gave an RMSECV of 1.75 IBU. The obtained prediction errors were compared to the errors given in the literature for the traditional extraction method of determining IBU. 相似文献
998.
Eberhard RITZ Ralf DIKOW Marie‐Luise GROSS 《Hemodialysis international. International Symposium on Home Hemodialysis》2007,11(Z1):S2-S11
Atherosclerosis, particularly coronary atherosclerosis, is accelerated in renal failure, as originally postulated by Belding Scribner. But in contrast to previous opinion, myocardial infarction from coronary heart disease is not the single major cause of cardiac death in dialyzed patients, the most common causes being sudden death and cardiac failure. Apart from coronary heart disease, the following cardiomyopathic features are prevalent and explain a large part of the excess cardiac risk: cardiomyocyte dropout, left ventricular hypertrophy, cardiac interstitial fibrosis, microangiopathy with arteriolar thickening, and capillary deficit as well as reduced ischemia tolerance. Recently, cardiovascular risk factors related to abnormal mineral metabolism, particularly phosphate and vitamin D, have gained unanticipated importance. Controlled evidence has become available concerning intervention with ACE inhibitors, angiotensin receptor blockers, β‐blockers, and statins in dialyzed patients. It is imperative that apart from the “classical” cardiovascular risk factors that do not exhaustively explain the excessive cardiovascular risk in dialyzed patients, novel pathomechanisms are considered and investigated; potential examples include depression, sleep abnormalities, etc. The above arguments do not negate the fact that today's modalities of renal replacement therapy are poor substitutes for the normal kidney's function so that as a result alternative strategies, e.g., daily dialysis, may also dramatically improve cardiovascular risk. 相似文献
999.
Claus Daniel Beth L. Armstrong Jane Y. Howe Narendra B. Dahotre 《Journal of the American Ceramic Society》2008,91(7):2138-2142
Tape-cast pseudo-cubic zirconia pellets were surface irradiated by two coherent interfering high-power short-pulse Nd:YAG laser beams. The interfering beams of the third harmonic with a wavelength of 355 nm of a 2.5-ns Q-switched laser produced a line-like intensity distribution with a periodic distance of 3.3 μm due to the selected angle between the beams. The resulting nonuniform surface heating produced a microstructure consisting of ultrafine-grained zirconia with a grain size of about 10 nm within the top 100–200 nm depth of the treated surface region due to the high cooling rates during short-pulse laser processing (up to 1010 K/s). The surface morphology closely followed the microperiodic heat treatment provided by the interfering laser beams. The pore size distribution within the periodic surface morphology ranged from a few nanometers to a maximum of half of the periodic line distances. 相似文献
1000.
Jane M Chi Barbara A Fink Richard M Hill G Lynn Mitchell 《Contact lens & anterior eye》2007,30(1):17-21
PURPOSE: The effects of sequencing of test conditions, in this case contact lens thicknesses, on the measurement of the oxygen shortfall of human corneas were studied. METHODS: Corneal oxygen uptake rates were measured with a Clark-type polarographic electrode on the central, unanesthetized right corneas of 14 human subjects. Measurements were made under the following conditions: (1) the normal open eye; (2) after 5 min of static (without blinking) wear of each of seven rigid gas permeable lenses of seven center thicknesses (0.18, 0.12, 0.16, 0.20, 0.24, 0.28, and 0.32 mm); (3) after 5 min of static wear of a polymethylmethacrylate (PMMA) contact lens. Lens thicknesses were randomly assigned numbers, which were sequenced in seven cycles. Two subjects were assigned to each sequencing cycle, and each subject participated in two identical sessions. RESULTS: The interaction of order x thickness was determined to be insignificant (F=0.99; p=0.5101). The effect of lens order was also insignificant (F=0.76; p=0.6239), indicating that the order of lens placement did not affect the measured corneal oxygen shortfall. Not surprisingly, the analysis indicated a significant effect of lens thickness on corneal oxygen shortfall (F=3.94; p=0.0032). CONCLUSIONS: The sequencing of lenses of various thicknesses on the cornea does not affect the measurement of corneal oxygen shortfall. 相似文献