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51.
Talcott Gerald W.; Fiedler Edna R.; Pascale Randy W.; Klesges Robert C.; Peterson Alan L.; Johnson Ronald S. 《Canadian Metallurgical Quarterly》1995,63(2):313
Weight gain after smoking cessation was studied in a naturalistic setting where (1) all smokers quit and (2) risk factors for postcessation weight gain were modified. Participants were 332 military recruits (227 men, 105 women), 86 of whom were smokers who quit during 6 weeks of basic training. Results showed no significant weight changes for smokers who quit. Pretest smoking rates and feat of weight gain were unrelated to changes in weight. Results suggest that an intensive program that limits access to alcohol and foods that are high in fat and that increases physical activity can attenuate weight gain after smoking cessation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Pinault M Pichot V Khodja H Launois P Reynaud C Mayne-L'Hermite M 《Nano letters》2005,5(12):2394-2398
We synthesized aligned multiwalled carbon nanotube multilayers by aerosol-assisted catalytic chemical vapor deposition through sequential injections of aerosols containing both carbon and catalyst precursors. Each sequence was traced by a specific duration or precursor mixture, with the carbon source being possibly enriched in (13)C isotope labels. We discovered that any sequence involved the growth of a new layer on the substrate surface, under any pre-existing one by lifting it up, giving definitive evidence of a base-growth mechanism. 相似文献
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Andrea Musi Pascale Massiani Dalil Brouri Jean-Michel Trichard Patrick Da Costa 《Catalysis Letters》2009,128(1-2):25-30
Reducing of nitrogen oxides (NO x ) in a lean exhaust gases has become one of the most important environmental concerns. Among the different active phases studied for NO x reduction reaction, silver-based catalysts supported over alumina show good performances using, as reducing agents, either hydrocarbons or oxygenated compounds. Nevertheless, a good understanding of the mechanism reaction has not been reached yet. This comprehension requires a better characterisation of the silver-based catalysts system. In our study, Ag/Al2O3 catalysts showed high efficiency in NO x reduction using ethanol as reducing agent. The conversion plots, in steady state conditions for the different samples Ag/Al2O3 (0.8–3.5% Ag wt), show a great dependance of the activity with the metal loading. The optimal silver loading has been established around 2 wt.% Increasing the silver loading, the temperature of maximal NO x conversion shifted toward the lower temperatures. According to the literature, a reduced and an oxide phase of silver have been observed by UV–Vis spectroscopy. The ratio between the two phases is changing with the silver loading. However, temperature programmed reduction (TPR) measurements reveal the presence of two types of oxide phases. TPR reveal the coexistence of a silver oxide phase (Ag2O), according to a production of water in the course of the reaction, and a non-oxygenated phase attributed to isolated Ag+ cation. Thus, an original way using TPR measurements has been developed to differentiate the various oxidized phases. The aim of this characterisation is to correlate the catalyst’s activity with the observed silver phases, in order to understand the nature of phase active for NO x reduction at low temperatures. 相似文献
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Firmesse O Alvaro E Mogenet A Bresson JL Lemée R Le Ruyet P Bonhomme C Lambert D Andrieux C Doré J Corthier G Furet JP Rigottier-Gois L 《International journal of food microbiology》2008,125(2):176-181
The objective of this study was to determine i) if Camembert cheese micro-organisms could be detected in fecal samples after regular consumption by human subjects and ii) the consequence of this consumption on global metabolic activities of the host colonic microbiota. An open human protocol was designed where 12 healthy volunteers were included: a 2-week period of fermented products exclusion followed by a 4-weeks Camembert ingestion period where 2x40 g/day of Camembert cheese was consumed. Stools were collected from the volunteers before consumption, twice during the ingestion period (2nd and 4th week) and once after a wash out period of 2 weeks. During the consumption of Camembert cheese, high levels of Lactococcus lactis and Leuconostoc mesenteroides were measured in fecal samples using real-time quantitative PCR, reaching median values of 8.2 and 7.5 Log(10) genome equivalents/g of stool. For Ln. mesenteroides, persistence was observed 15 days after the end of Camembert consumption. The survival of Geotrichum candidum was also assessed and the fecal concentration reached a median level of 7.1 Log(10) CFU/g in stools. Except a decreasing trend of the nitrate reductase activity, no significant modification was shown in the metabolic activities during this study. 相似文献
59.
Ozone (O3) chemistry is thought to dominate the oxidation of indoor surfaces. We consider the hypothesis that reactions taking place within indoor boundary layers result in greater than anticipated hydroxyl radical (OH) deposition rates. We develop models that account for boundary layer mass‐transfer phenomena, O3‐terpene chemistry and OH formation, removal, and deposition; we solve these analytically and by applying numerical methods. For an O3‐limonene system, we find that OH flux to a surface with an O3 reaction probability of 10?8 is 4.3 × 10?5 molec/(cm2 s) which is about 10 times greater than predicted by a traditional boundary layer theory. At very low air exchange rates the OH surface flux can be as much as 10% of that for O3. This effect becomes less pronounced for more O3‐reactive surfaces. Turbulence intensity does not strongly influence the OH concentration gradient except for surfaces with an O3 reaction probability >10?4. Although the O3 flux dominates OH flux under most conditions, OH flux can be responsible for as much as 10% of total oxidant uptake to otherwise low‐reactivity surfaces. Further, OH chemistry differs from that for ozone; therefore, its deposition is important in understanding the chemical evolution of some indoor surfaces and surface films. 相似文献
60.
Megan E. Salwei Pascale Carayon Ann S. Hundt Peter Hoonakker Vaibhav Agrawal Peter Kleinschmidt 《Ergonomics》2019,62(7):864-879
Hospitals are complex environments that rely on clinicians working together to provide appropriate care to patients. These clinical teams adapt their interactions to meet changing situational needs. Venous thromboembolism (VTE) prophylaxis is a complex process that occurs throughout a patient’s hospitalisation, presenting five stages with different levels of complexity: admission, interruption, re-initiation, initiation, and transfer. The objective of our study is to understand how the VTE prophylaxis team adapts as the complexity in the process changes; we do this by using social network analysis (SNA) measures. We interviewed 45 clinicians representing 9 different cases, creating 43 role networks. The role networks were analysed using SNA measures to understand team changes between low and high complexity stages. When comparing low and high complexity stages, we found two team adaptation mechanisms: (1) relative increase in the number of people, team activities, and interactions within the team, or (2) relative increase in discussion among the team, reflected by an increase in reciprocity.
Practitioner Summary: The reason for this study was to quantify team adaptation to complexity in a process using social network analysis (SNA). The VTE prophylaxis team adapted to complexity by two different mechanisms, by increasing the roles, activities, and interactions among the team or by increasing the two-way communication and discussion throughout the team. We demonstrated the ability for SNA to identify adaptation within a team. 相似文献