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21.
To assess predictors of latent tuberculosis infection (LTBI) completion by using structural equation modeling (SEM) among homeless adults, a group at great risk for LTBI and active tuberculosis (TB). LTBI therapy is effective in stemming the progression to active TB, yet treatment adherence among homeless persons is difficult to attain. Design: By using SEM, the authors assessed predictors of LTBI completion among a sample of 494 homeless adults in Los Angeles, CA, who received either a nurse case-managed program (NCM) or a usual care program. Main Outcome Measures: Latent variables were created with the baseline variables of site type, age, intervention status, dissatisfaction with health care, depression, TB risk assessment, alcohol use, heroin or cocaine use, and TB knowledge. Outcome variables included many of the same baseline variables as well as treatment completion. Results: LTBI treatment completion (100% adherence) was significantly and positively associated with participation in NCM, older age, and less heroin or cocaine use. NCM also predicted greater TB knowledge, greater ease of treatment, and more satisfaction with treatment (NCM completion rate = 64%, control rate = 42%). Conclusion: The culturally competent NCM program, combined with active tracking and incentives, was successful in a difficult-to-treat and highly transient population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
The authors examined the effects of activity wheel running (AWR) and propranolol on contextual fear conditioning (CFC) and messenger RNA (mRNA) for galanin (GAL) in the locus coeruleus (LC) and brain-derived neurotrophic factor (BDNF) in the hippocampal formation (HF) in rats. Freezing behavior during the testing session of the CFC protocol was elevated in the AWR-placebo group compared to sedentary-placebo and AWR-propranolol groups. AWR increased GAL mRNA in the LC. CFC increased BDNF mRNA in the HF. These results suggest that exercise enhances CFC and that antagonism of the β-adrenoreceptors attenuates this effect. The exercise-related induction of GAL gene expression in the LC may influence noradrenergic transmission to facilitate CFC. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
The use of a multi-ecological tracer approach provides valuable and complementary insights to investigate the complex biology and ecology of large pelagic fish. Brine immersion freezing is the most common preservation technique used onboard for large fish to be frozen whole until they are delivered for sale and processing. We evaluated the effect of brine freezing on lipid and fatty acid composition, C and N stable isotope ratios, and organochlorine contaminant levels of yellowfin tuna (Thunnus albacares) and skipjack tuna (Katsuwonus pelamis). Fresh tunas were stored in a saturated sodium chlorine brine immersion tank maintained at ?20 °C for 6 weeks, and ecological tracers were analysed on dorsal muscle samples collected before and after brine freezing. No significant effect of the fish preservation technique was found except for δ15N whose signatures slightly increased after a 6-week period of brine immersion. Because N isotopic shift was close to the analytical precision and probably related to a higher risk of salt penetration in small tunas with abraded skin, we consider our results as conservative and conclude that ecological tracers can indeed be analysed on brine-freezing-preserved tunas.  相似文献   
24.
25.
Ohmic minority and majority drift mobilities as well as saturation velocities are reported for unstrained and strained Si1-xGe x alloys up to z=0.31. The electron-transport model is verified by measurements of the in-plane majority drift mobility in strained Si1-xGex samples for various dopant and Ge concentrations. Saturation velocities are determined by full-band Monte Carlo simulations. There is no substantial decrease in the mobility perpendicular to the Si/SiGe interface for doping concentrations above 1019 cm-3 and growing x. In contrast, the saturation-drift velocity is strongly reduced with x  相似文献   
26.
Two separate path models for alcohol and drugs were tested in which psychosocial, environmental, and sociodemographic variables predicted behavioral and substance abuse related factors as well as the key outcome of positive attitudes about quitting drugs (N = 620) or alcohol (N = 526) in a sample of 709 homeless women. A positive attitude about quitting alcohol was predicted by more Addiction Symptoms, fewer Positive Effects from using alcohol, and not having a partner who uses alcohol. A positive attitude about quitting drugs was predicted by more Drug Problems, greater Drug Use in the Past 6 Months, more Active Coping, more education, less Emotional Distress, not having a partner who uses drugs, and fewer Addiction Symptoms. Implications of the results for drug and alcohol interventions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
The work presented in this article concerns polluted marine sediments. The article is divided into three parts. The first part discusses existing industrial procedures of treatment. The second part introduces the Novosol((R)) process, which was used for the treatment of polluted marine sediments. This process is based on the stabilization of heavy metals in the solid matrix by phosphatation and the destruction of organic matter by calcination. Finally, after a comparison had been made between environmental results obtained on both polluted marine sediments and inert ones, treated sediments were introduced in the production of clay bricks. The results obtained show that the Novosol process leads to the immobilization of most heavy metals and can be considered as an efficient tool for the stabilisation of polluted marine sediment. Thus, the results of physical and mechanical tests as compressive strength and water absorption indicate that performances obtained were comparable to standard brick values. These results confirm that, once treated, polluted sediments can be recycled.  相似文献   
28.
The use of ion implantation doping instead of the standard gaseous diffusion is a promising way to simplify the fabrication process of silicon solar cells. However, difficulties to form high‐quality boron (B) implanted emitters are encountered when implantation doses suitable for the emitter formation are used. This is due to a more or less complete activation of Boron after thermal annealing. To have a better insight into the actual state of the B distributions, we analyze three different B emitters prepared on textured Si wafers: (1) a BCl3 diffused emitter and two B implanted emitters (fixed dose) annealed at (2) 950°C and at (3) 1050°C (less than an hour). Our investigations are in particular based on atom probe tomography, a technique able to explore 3D atomic distribution inside a material at nanometer scale. Atom probe tomography is employed here to characterize B atomic distribution inside textured Si solar cell emitters and to quantify clustering of B atoms. Here, we show that implanted emitters annealed at 950 °C present maximum clusters due to poor solubility at lower temperature and also highest emitter saturation current density (J0e = 1000 fA/cm2). Increasing the annealing temperature results in greatly improved J0e (131 fA/cm2) due to higher solubility and a consequently lower number of clusters. BCl3 diffused emitters do not contain any B clusters and presented the best emitter quality. From our results, we conclude that clustering of B atoms is the main reason behind higher J0e in the implanted boron emitters and hence degraded emitter quality. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
29.
The J–V curves recorded under illumination for solar cells having a high series resistance can appear shunted when a fraction of the cell area is affected by very high series resistance values. This “apparent shunting” behaviour was observed in n‐type rear‐junction, laser‐doped cells with light‐induced plated front contacts. Localized series resistance measurements of the affected cells by photoluminescence imaging revealed that over 20% of the cell area had a series resistance above 10 Ω cm2 and extending up to a maximum value of 168 Ω cm2. It was found that cells with localized series resistances have a detrimental impact on the FF and Jsc of the device. Furthermore, an unusual FF recovery was also observed with decreasing level of illumination. A solar cell model with localized high series resistances was developed to further study this “apparent shunting” behaviour with respect to its impact on cell performance. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
30.
Volatile compounds from fresh and dried mango were extracted by the solvent‐assisted flavour evaporation (SAFE) technique and analysed by GC‐MS. Forty‐one and fifty five volatile compounds were identified in fresh and dried mango, respectively. Monoterpenes, followed by sesquiterpenes, lactones and alcohols were the major compounds. Drying induced substantial losses of several compounds. The total amount of volatiles decreased by about 59%. These losses could be mainly attributed to the evaporation of the volatiles during drying, the extent of which seemed to increase with the hydrophobicity and Henry's law constant of the compounds. However, new compounds appeared and enrichment of some compounds was observed after drying. Limonene, β‐myrcene, δ‐3‐carene, β‐caryophyllene, γ‐butyrolactone and 3‐methylbutyl butanoate were found to be flavour contributors in both products on the basis of the odour activity values (OAVs). Mesifuran displayed high OAV only in fresh fruit while hexanal and heptanal only in dried mango.  相似文献   
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