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11.
The current work investigates how personality and interpersonal processes combine to predict change in relationship quality. Measures of personality and emotion similarity were collected during laboratory interactions from a cross-sectional sample of dating couples (Study 1) and a 1-year longitudinal study of newlywed married couples (Study 2). Results showed that emotion similarity mediated the association between personality similarity and relationship quality (Studies 1 and 2) and that emotion convergence mediated the association between personality convergence and relationship satisfaction (Study 2). These results indicate that similarity and convergence in personality may benefit relationships by promoting similarity and convergence in partners' shared emotional experiences. Findings also lend support to models that integrate partners' enduring traits and couples' adaptive processes as antecedents of relationship outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
Diets high in omega-6 polyunsaturated fatty acids (n-6) are associated with increased prostaglandin F (PGF) synthesis in cattle, however, the specific effects on the potential prostaglandin response to an oxytocin challenge in sheep have not been reported. The aim of the current study was to determine whether oxytocin-stimulated PGF was significantly increased when ewes were fed a diet high in n-6 compared with a control diet low in n-6. Merino x Border Leicester ewes (n = 30) received one of two dietary treatments, either high in n-6 (70 % oat grain) or low in n-6 (control diet, 100 % cereal/legume silage). Ewes consumed the diets for 44 days prior to two consecutive oxytocin challenges. Plasma n-6 and PGF metabolite (PGFM) concentrations following oxytocin challenge were greater (P < 0.05) when ewes were fed a diet high in n-6 compared with the control diet. A higher availability of n-6 may have lead to an increased in vivo synthesis of PGF, however, further research is required to determine the exact mechanisms involved.  相似文献   
13.
The cyclic fatigue life of zirconia bioceramic was determined under biaxial flexion using disk-shaped specimens. The fatigue life was not reduced by subjecting the material to a simulated physiological environment nor was it affected by testing at different loading frequencies. Tests performed at different stress ratios produced a large degree of scatter in the data but a statistical analysis proved that there was no significant effect on the fatigue life of the material. Failure of disk specimens was initiated either by flaws introduced during manufacturing or by the more typical inherent flaws commonly observed in ceramics. The former generally resulted in premature, low-stress failures on initial loading whereas the latter acted as initiating defects for fatigue cracks that then propagated to failure. The distributions of the two categories of flaw were analyzed using two- and three-parameter Weibull probability functions. It became clear that the Weibull modulus for the fatigue failures was consistent with previously reported work on other ceramics.  相似文献   
14.
The aim of this study was to investigate the treatment efficiency of passive vertical‐flow wetland filters containing Phragmites australis and/or Typha latifolia and granular media of different adsorption capacities. A cost–benefit analysis was performed on the characteristics of constructed wetlands. Cheap gravel and sand as well as expensive granular activated carbon, charcoal and Filtralite (light expanded clay) were used as filter media. Different concentrations of lead and copper sulfate were added to polluted urban beck inflow water in order to simulate pre‐treated mine wastewater, landfill leachate or highway runoff. The relationships between growth media, microbial and plant communities as well as the reduction of lead, copper, five‐day biochemical oxygen demand (BOD) in particular, and potentially pathogenic bacteria were investigated. A breakthrough of copper within the first 9 weeks was only recorded for filters containing media with limited adsorption capacities. The breakthrough was independent of the presence of plants. However, after maturation of the biomass, which dominated the schmutzdecke and litter zone, lead and copper concentrations were reduced by 97–99% and BOD by 41–60% in all wetlands. There appears to be no additional benefit in using macrophytes and expensive adsorption media in constructed wetlands to enhance metal reduction during the set‐up period of 5 months. © 2001 Society of Chemical Industry  相似文献   
15.
Objective: Secondhand smoke exposure is associated with asthma onset and exacerbation. Latino children have higher rates of asthma morbidity than other groups. The current study compared the effectiveness of a newly developed smoking cessation treatment with existing clinical guidelines for smoking cessation. Method: Latino caregivers who smoked (N = 133; 72.9% female; mean age = 36.8 years) and had a child with asthma were randomly assigned to receive 1 of 2 smoking cessation counseling interventions during a home-based asthma program: (a) behavioral action model (BAM; modeled on clinical guidelines for smoking cessation) or (b) precaution adoption model (PAM; feedback on the caregiver’s carbon monoxide level and child’s secondhand smoke exposure using Motivational Interviewing). Counseling was delivered by a bilingual Latina health educator, and the content was tailored to Latino values and culture. It was not necessary for smokers to want to quit smoking to participate. Smoking cessation was biochemically verified and secondhand smoke exposure was objectively measured through passive nicotine monitors. Results: Intent-to-treat analyses showed that 20.5% of participants in the PAM condition and 9.1% of those in the BAM condition were continuously abstinent at 2 months posttreatment (OR = 2.54; 95% CI = 0.91–7.10), whereas 19.1% of participants in the PAM condition and 12.3% of those in BAM condition were continuously abstinent at 3 months posttreatment (OR = 1.68; 95% CI = 0.64–4.37). Secondhand smoke exposure decreased only in the BAM condition (p p  相似文献   
16.
Few researchers have studied whether weight gain has an impact on short-term relapse to smoking. The authors of this study investigated predictors of relapse among 989 participants (60% women) in a randomized, double-blind, 10-week multicenter trial to determine the effect of fluoxetine (30 or 60 mg) versus placebo in combination with behavioral counseling for smoking cessation. Medication compliance and smoking status were biochemically verified. At Visit 2, participants were asked to set a quit date within the subsequent 2 visits. A proportional hazards regression model was used to predict risk of relapse within the first 3 months of quitting. Weight gain predicted relapse, but for men only. Female gender also predicted relapse. The results led the authors to question whether postcessation weight gain interventions should be restricted to women smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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18.
Woody yard waste with high lignin content (22% of dry matter (DM)) was subjected to wet oxidation pre‐treatment for subsequent enzymatic conversion and fermentation. The effects of temperature (185–200 °C), oxygen pressure (3–12 bar) and addition of sodium carbonate (0–3.3 g per 100 g DM biomass) on enzymatic cellulose and hemicellulose (xylan) convertibility were studied. The enzymatic cellulose conversion was highest after wet oxidation for 15 min at 185 °C with addition of 12 bars of oxygen and 3.3 g Na2CO3 per 100 g waste. At 25 FPU (filter paper unit) cellulase g?1 DM added, 58–67% and 80–83% of the cellulose and hemicellulose contained in the waste were converted into monomeric sugars. The cellulose conversion efficiency during a simultaneous saccharification and fermentation (SSF) assay at 10% DM was 79% for the highest enzyme loading (25 FPU g?1 DM) while 69% conversion efficiency was still reached at 15 FPU g?1 DM. Total carbohydrate recoveries were high (91–100% for cellulose and 72–100% for hemicellulose) and up to 49% of the original lignin and 79% of the hemicellulose could be solubilized during wet oxidation treatment and converted into carboxylic acids mainly (total carboxylic acids = 3.1–7.4% on DM basis). Copyright © 2004 Society of Chemical Industry  相似文献   
19.
Background: Persons on peritoneal dialysis and hemodialysis with preserved residual renal function experience lower mortality rates than those without. Previous studies have shown slower rates of decline of residual renal function for peritoneal dialysis (PD)(2 to 3% decrease/month), compared with hemodialysis (HD)(6 to 7% decrease/month). However, our clinical observations suggested a lower rate of decline in hemodialysis patients. Methods: We evaluated data in 174 hemodialysis patients cared for from January 2000 through October 2001. Eighty‐seven (50%) patients had at least two timed quarterly urine collections to estimate the rate of change of residual renal function over time (urea clearance, or KrU). All patients underwent thrice‐weekly hemodialysis using polysulfone dialyzers with formaldehyde reprocessing. The rate of decline of residual renal function and the effect of KrU on laboratory variables were estimated using a random effects (MIXED) model, adjusting for the effects of age, sex, race, diabetes, and dialysis vintage. Results: The mean KrU at baseline was 3.5 mL/min. Men (P < 0.001) and persons of shorter vintage (P < 0.0001) had more residual renal function at baseline. The estimated rate of decline of residual renal function was ? 0.07 mL/min/month (? 1.9% decrease/month). The rate of decline in residual renal function was unaffected by sex, race, diabetes, or vintage, although the rate of decline was significantly attenuated among older individuals (age x time interaction, P = 0.01). Serum phosphorus (P = 0.03) and the calcium x phosphorus product (P = 0.009) increased over time and were influenced by the level of residual renal function (P = 0.06 and P = 0.006, respectively). Residual renal function did not influence the rate of change of other laboratory variables. Conclusions: In an ethnically diverse cohort of hemodialysis patients, the rate of decline of residual renal function was relatively slow and age dependent, as well as consistent with values others have reported for patients on peritoneal dialysis. Universal use of biocompatible dialyzers and bicarbonate dialysate may have contributed to differences discussed in prior reports. Residual renal function attenuated the increase in calcium–phosphorus product over time. A better understanding of the determinants of the rate of decline in residual renal function, and the specific benefits afforded to patients via maintenance of residual renal function, would help to inform the debates on timing of initiation and various dosing strategies in hemodialysis.  相似文献   
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