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排序方式: 共有494条查询结果,搜索用时 15 毫秒
41.
Louise C W Wiggers Frans J Oort Ron J G Peters Dink A Legemate Hanneke C J M de Haes Ellen M A Smets 《Nicotine & tobacco research》2006,8(4):581-589
The benefits of smoking cessation on patients' medical conditions are well documented. Cardiovascular patients who quit smoking significantly reduce their risk of a new event compared with those who continue smoking. Several studies have found that smoking is related to poor quality of life (QoL). In cardiovascular patients, however, less attention has been given to the effect of smoking cessation on patients' QoL. The present study examined the extent to which smoking cessation leads to changes in QoL in these patients within the first year of follow-up. Data were collected in the context of a randomized clinical trial. Smoking outpatients (N = 346) with atherosclerotic disease were included and received medical treatment. They were randomized to receive either nicotine replacement therapy (NRT) or NRT plus a behavioral intervention meant to promote smoking cessation. At baseline, sociodemographic and clinical characteristics were established. Generic and disease-specific QoL as well as smoking status were assessed at baseline and with three follow-up measurements. Multilevel modeling showed that generic and disease-specific QoL in atherosclerotic patients improved significantly within the first year of follow-up. No main differences were found between quitters and smokers in terms of improvement in QoL. In fact, some subgroups reported a poorer QoL after smoking cessation: More highly educated patients reported lower general QoL (p < .05), and patients suffering from coronary artery disease who had a low level of education (p < .01) and patients suffering from peripheral arterial disease who had low nicotine dependency (p < .01) reported lower disease-specific QoL. Atherosclerotic patients' QoL improved significantly but was not enhanced by smoking cessation activities. 相似文献
42.
Mit Einführung eines Dokumentmanagement-und Vorgangsbearbeitungssystems (DMS) muss sich die Verwaltung der Herausforderung
der automatisiert erfolgenden Protokollierung stellen. An einem DMS zeigt sich u.a. sehr deutlich, dass verschiedene Typen
von Protokolldaten zu unterscheiden sind. 相似文献
43.
Hlne Monteillet Marcel Workamp Jeroen Appel J. Mieke Kleijn Frans A. M. Leermakers Joris Sprakel 《Advanced Materials Interfaces》2014,1(7)
Microgel particles display an interesting duality with properties attributed typically both to polymeric and colloidal systems. When adsorbed at a liquid‐liquid interface, this duality becomes particularly apparent as the various phenomena at play are governed by different aspects of these soft and responsive particles. The introduction of a solid, fluorescently labeled, polystyrene core into the microgels allows direct and accurate visualization without the necessity of potential perturbing sample preparation techniques. By combining in‐situ imaging and tensiometry, we determine that composite microgels at a wide variety of oil‐water interfaces anchor strongly, with adsorption energies of approximately 106 kBT, typical for particle adsorption, yet accumulate at the interface spontaneously without any energy barrier, which is more typical for polymers. The high adsorption energies allow the particle to spontaneously form very dense crystalline packings at the liquid interface in which the microgels are significantly compressed with respect to their swollen state in bulk solutions. Finally, we demonstrate the unique nature of these particles by producing highly stable and monodisperse microgel‐stabilized droplets using microfluidics. 相似文献
44.
The effect of fuel composition on the thermodynamic efficiency of gasifiers and gasification systems is studied. A chemical equilibrium model is used to describe the gasifier. It is shown that the equilibrium model presents the highest gasification efficiency that can be possibly attained for a given fuel. Gasification of fuels with varying composition of organic matter, in terms of O/C and H/C ratio as illustrated in a Van Krevelen diagram, is compared. It was found that exergy losses in gasifying wood (O/C ratio around 0.6) are larger than those for coal (O/C ratio around 0.2). At a gasification temperature of 927 °C, a fuel with O/C ratio below 0.4 is recommended, which corresponds to a lower heating value above 23 MJ/kg. For gasification at 1227 °C, a fuel with O/C ratio below 0.3 and lower heating value above 26 MJ/kg is preferred. It could thus be attractive to modify the properties of highly oxygenated biofuels prior to gasification, e.g. by separation of wood into its components and gasification of the lignin component, thermal pre-treatment, and/or mixing with coal in order to enhance the heating value of the gasifier fuel. 相似文献
45.
Two paradigms for distributed shared memory on loosely-coupled computing systems are compared: the shared data-object model as used in Orca, a programming language specially designed for loosely-coupled computing systems, and the shared virtual memory model. For both paradigms two systems are described, one using only point-to-point messages, the other using broadcasting as well. The two paradigms and their implementations are described briefly. Their performances are compared on four applications: the travelling-salesman problem, alpha-beta search, matrix multiplication and the all-pairs shortest-paths problem. Measurements were obtained on a system consisting of 10 MC68020 processors connected by an Ethernet. For comparison purposes, the applications have also been run on a system with physical shared memory. In addition, the paper gives measurements for the first two applications above when remote procedure call is used as the communication mechanism. The measurements show that both paradigms can be used efficiently for programming large-grain parallel applications, with significant speed-ups. The structured shared data-object model achieves the highest speed-ups and is easiest to program and to debug. 相似文献
46.
Joseph I. Goldstein Seung K. Choi Frans J. J. Van Loo Guillaume F. Bastin Rudi Metselaar 《Journal of the American Ceramic Society》1995,78(2):313-322
Reactions between Ti and SiO2 were studied at 1373 K (1100°C) under vacuum conditions using planar diffusion couples. A method to correct for the presence of surface oxide was developed which led to improved oxygen measurements with the electron probe microanalyzer. An isothermal section through the Ti-Si-O phase diagram at 1373 K was determined using measured diffusion paths and phase compositions in equilibrated alloys. The experimentally determined isothermal section was compared to isothermal sections calculated using thermodynamic data. In addition the sequence of reaction layers formed in the diffusion couples is discussed in terms of thermodynamic activity diagrams. 相似文献
47.
Social learning is assumed to underlie traditions, yet evidence indicating social learning in capuchin monkeys (Cebus apella), which exhibit traditions, is sparse. The authors tested capuchins for their ability to learn the value of novel tokens using a previously familiar token-exchange economy. Capuchins change their preferences in favor of a token worth a high-value food reward after watching a conspecific model exchange 2 differentially rewarded tokens, yet they fail to develop a similar preference after watching tokens paired with foods in the absence of a conspecific model. They also fail to learn that the value of familiar tokens has changed. Information about token value is available in all situations, but capuchins seem to pay more attention in a social situation involving novel tokens. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Frans M.M. Snijkers Anita Buekenhoudt Jan J. Luyten Jos Cooymans Myrjam Mertens 《Scripta materialia》2004,51(12):1129-1134
Yttria doped Ba-hafnates were prepared by solid state route and the proton conductivity of pressed samples of yttria doped barium hafnate was determined with impedance spectroscopy. The results are compared with existing data for cerates and zirconates. It was found that Ba-hafnates show a level of proton conduction that is comparable to that of doped Ba-zirconates at low and slightly higher at high temperatures. This is in agreement with the prediction based on the ionic radius of the tetravalent atom in the perovskite. 相似文献
49.
Two measures are reported of the nature or quality of a mother-offspring (MO) relationship during development using brown capuchin monkeys (Cebus apella) as models. One is a qualitative classification of MO relationships as secure, resistant, or avoidant attachments. The other is an empirical ratio of relative affiliation to agonism called the MO relationship quality, or MORQ, Index. The two methods tapped similar relationship features so relationships high or low of a median split of MORQ values were heuristically labeled secure (n = 22) or insecure (n = 16), respectively. A comparison revealed extensive behavioral differences between secure and insecure MO relationships and suggested MORQ provided an objective, continuous measure of attachment security. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Wohlfarth Tamar D.; van den Brink Wim; Winkel Frans Willem; ter Smitten Mario 《Canadian Metallurgical Quarterly》2003,15(1):101
The validity of the Impact of Events Scale (IES) and the Posttraumatic Stress Disorder (PTSD) Symptom Scale, Self-Report version (PSS-SR) was examined among crime victims. Both instruments performed well as screeners for PTSD. For the IES, sensitivity ranged between .93 and 1.00; for the PSS-SR, sensitivity ranged between .80 and .90. Specificity for the IES ranged between .78 and .84 and for the PSS-SR ranged between .84 and .88. Some individual items from the 2 scales performed just as well as the total scales. The authors conclude that either of these short self-report instruments or their individual items are suitable as screeners for PTSD, specifically in settings where mental health professionals are unavailable. Cross-validation of these results is necessary because of the small sample size in this study. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献