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排序方式: 共有1283条查询结果,搜索用时 859 毫秒
121.
Assertive community treatment (ACT) programs have made substantial strides in reducing inpatient hospitalizations and in improving the lives of individuals with a severe mental illness. However, few studies have investigated their effectiveness outside of a 24-month treatment period. The present study investigated treatment outcomes in an ACT program over a 36-month period. Results indicate that participants experienced a statistically significant reduction in hospital bed days during the first 2 years of treatment. Positive outcomes were demonstrated on other variables, including an increase in compliance with outpatient psychiatric appointments and a reduction in emergency outpatient contacts. Results indicate that clients and family members were satisfied overall with ACT services, but family members reported greater satisfaction than clients in all areas assessed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
122.
A simple model has been developed to predict the removal of hydrocarbon fractions from wastewater using sacrificial Al anodes. The model was successfully applied to the interpretation of experimental data obtained in a laboratory electrochemical cell operated in a batchwise manner. The adsorption equilibrium of organic matter on Al hydroxide was modelled using three equations, with the best results obtained using a Langmuir-type equation. The model was able to describe the effects of current density and pollutant concentration on the efficiency of wastewater treatment. Different values were obtained for the parameters depending on the nature of the hydrocarbon suspension. Aluminium hydroxide showed a far higher affinity for the oil/kerosene suspension but exhibited a higher capacity to remove heavy oil suspensions. The removal rates of pollutants were found to depend on the initial concentration and the current density. When the current density was sufficient to destabilise the emulsion, the zeta potential of the clear fraction measured at pH 7.0 became positive. This change was also characterised by a significant reduction in turbidity. Furthermore, the application of higher current densities did not allow further treatment of the water. However, the efficiency of emulsion destabilisation was found to depend on the concentration and current densities that were too low were ineffective. 相似文献
123.
Ahmed Hammami Denise Chang-Yen John A. Nighswander Ellen Stange 《Petroleum Science and Technology》1995,13(9):1167-1184
Asphaltene onset concentration and bulk deposition were measured for a typical live reservoir oil titrated with n-C6H14, n-C5H12, n-C4H10, C3H8, C2H6, CH4 and CO2 at 100° C (212 ° F) and 29.9 MPa (4340 psia). The concentration of titrant at asphaltene onset was observed to decrease approximately in a linear fashion with decreasing molecular weight of the paraffinic solvent; CH4 did not induce any asphaltene precipitation. Bulk deposition experiments were performed using a solvent: oil volume ratio of 10:1; the results indicated that the weight percent of asphaltenes precipitated increased exponentially with decreasing molecular weight of the paraffinic solvents. More importantly, the asphaltene molecular weight showed a maximum for n-C4H10 precipitated asphaltenes. Possible explanations for this unusual result are presented. 相似文献
124.
This study compared the sensitivity and teaching strategies of dysphoric and nondysphoric women working with unfamiliar 5- and 6-year-olds. Interactions of 20 dysphoric and 20 nondysphoric mothers and an unfamiliar child were observed during 2 classification tasks and 3 unstructured activities staged as breaks. Nondysphoric women were more sensitive to children's level of understanding than dysphoric women and were more likely to use a variety of teaching strategies. Dyads with nondysphoric women were also more likely to share decision making than dyads with dysphoric women. These differences between dysphoric and nondysphoric women were significant only in the structured classification tasks. The findings indicate that in some situations dysphoric and nondysphoric women vary in their sensitivity to children's cues and in the teaching strategies they use with children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
125.
Definitions of business process given in much of the literature on Business Process Management are limited in depth and their related models of business processes are correspondingly constrained. After giving a brief history of the progress of business process modeling techniques from production systems to the office environment, this paper proposes that most definitions are based on machine metaphor type explorations of a process. While these techniques are often rich and illuminating it is suggested that they are too limited to express the true nature of business processes that need to develop and adapt to today's challenging environment. 相似文献
126.
Morelli Gilda A.; Rogoff Barbara; Oppenheim David; Goldsmith Denise 《Canadian Metallurgical Quarterly》1992,28(4):604
Examines the decisions of middle-class US and Highland Mayan parents regarding sleeping arrangements during their child's 1st 2 yrs and their explanations for their differing practices. All 14 Mayan children slept in their mothers' beds into toddlerhood. None of the 18 US infants slept in bed with their mothers on a regular basis as newborns, although 15 slept near their mothers until age 3–6 mo, when most were moved to a separate room. The Mayan parents explained their practices in terms of the value of closeness with infants; US parents explained their practices in terms of the value of independence for infants. US families, but not Mayan families, used bedtime routines and objects to facilitate the transition to sleep. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
127.
McAweeney Mary J.; Forchheimer Martin; Tate Denise G. 《Canadian Metallurgical Quarterly》1997,42(2):125
Reviews the value of null statistical hypothesis testing and discuss its limitations and misuses. It is contended that this method is of nominal utility in outcomes research, that rehabilitation researchers should focus on the calculation and interpretation of statistical power and effect size. During this era when outcomes are paramount, researchers in rehabilitation psychology cannot afford to conduct studies where significant methodological shortcomings compromise the validity of the results. Study design, evaluation, and presentation recommendations for the appropriate use and interpretation of statistical analysis in outcomes research are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
128.
Study of the modulus of elasticity of polymer concrete compounds and comparative assessment of polymer concrete and portland cement concrete 总被引:1,自引:0,他引:1
The main aim of this study is to assess the modulus of elasticity of polymer concrete (PC) compounds produced using two types of binders: orthophtalic or isophtalic polyester. The compositions used were selected from a previous study that identified cost-effective PC compositions. Based on those data, the concentrations of polymer used were 12% of orthophtalic polyester and 13% of isophtalic polyester by weight of the dry materials. Fly ash was used as a filler and compositions with 8%, 12%, 16% and 20% of ash by weight of aggregate were studied. Results indicate that all compositions assessed in this study display high modulus of elasticity values. Statistical analysis of the data reveals that the type of resin and the concentration of fly ash, both in isolation and in combination, have a significant effect on the modulus of elasticity of these compounds. 相似文献
129.
Zelazo Philip David; Reznick J. Steven; Pi?on Denise E. 《Canadian Metallurgical Quarterly》1995,31(3):508
Two-year-olds' difficulty with rule execution is robust and pervasive. In Experiment 1, 120 32-month-olds received 1 of 6 tasks: a task assessing knowledge about a series of items; a deductive card sort requiring children to use their knowledge to sort the items by rules; and 4 modifications of the card sort that provided various types of task support. Children performed better on the knowledge task than the other tasks, which did not differ. Errors increased over trials and were typically perseverative. Experiment 2 replicated the finding that children failed to use rules systematically even when items were labeled by the rules' antecedents. Improvements in rule use seem to reflect emerging control over actions rather than increased representational flexibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
130.
Denise C. Hunter Jingli Zhang Lesley M. Stevenson Margot A. Skinner 《International Journal of Food Science & Technology》2008,43(12):2123-2129
Developing functional food products requires a structured approach for screening potential ingredients. Using the development of a product with antioxidant properties as a model, eight fruit juice concentrates were screened, including New Zealand fruits. The total phenolic content and the antioxidant capacity, using chemical‐based assays (ferric reducing antioxidant power and oxygen radical absorbance capacity assays), were determined. The potential to protect against oxidative stress in Jurkat cells was also determined. Results indicate that the total phenolic content and antioxidant capacity in chemical‐based assays were strongly correlated. However, the total phenolic content did not dictate the level of protection from oxidative stress in this cell‐based model, suggesting that the type of phenolic compounds present and interactions between them may be important, although the activity of other compounds, such as vitamin C or carotenoids, may also be implicated. This model for screening ingredients may be used to design synergistic combinations of ingredients, and results may provide supportive evidence in the development of functional foods for this and other health targets. 相似文献