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21.
Wildman Robert W. II; Weathers Anne V.; Patterson Malcolm E.; Nelson Fredrick R.; Thompson Leslie; Laosa Mario De Jr.; Wildman Robert W. 《Canadian Metallurgical Quarterly》1978,9(4):602
A psychology section functioning in a forensic services center is described. The legal questions that must be dealt with in such a setting are explained, and psychology's role in answering these questions is explored. The goals of treatment in a forensic unit, which focus on educating a defendant to competency for trial, are discussed, and an example of a treatment program is presented. The functions of a psychologist in a forensic setting are compared and contrasted with those of a psychologist in the general mental health field. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
The availability of different forages varies across landscapes, but little is known about how proportional consumption of
different foods affects food intake and the use of landscapes. The relative amounts of nutrients and plant secondary metabolites
(PSM) consumed by herbivores may influence forage intake and animal fitness in landscapes dominated by plants with PSM. Our
objective was to determine if the relative availability of nutritious foods that contain PSM affected food preference and
intake by lambs. Lambs in three treatments (eight lambs/treatment) were offered two PSM-containing foods at different relative
availabilities: treatment 1—ad libitum terpene- and 100-g tannin-containing food, treatment 2—ad libitum tannin- and 100-g terpene-containing food, and treatment 3—ad libitum access to both tannin- and terpene-containing foods. We measured intake of individual foods and total intake of PSM-containing
foods during conditioning and a preference test, where animals were offered both PSM-containing foods ad libitum. When lambs were fed 100 g of the tannin-containing food, they ingested more terpene and total PSM (P < 0.05) than when both PSM were offered ad libitum, but limiting terpenes did not affect intake of tannin or total intake of PSM (P > 0.10). During preference tests, all groups preferred tannins over terpenes, but lambs in the treatment fed 100 g of tannin
had a higher preference for terpenes than did lambs in the other two treatments (P < 0.10). These results support the notion that the relative amounts of PSM consumed affects intake and preference for PSM-containing
foods by herbivores. 相似文献
23.
Samaha MA Ochanda FO Tafreshi HV Tepper GC Gad-el-Hak M 《The Review of scientific instruments》2011,82(4):045109
Light scattering was used to measure the time-dependent loss of air entrapped within a submerged microporous hydrophobic surface subjected to different environmental conditions. The loss of trapped air resulted in a measurable decrease in surface reflectivity and the kinetics of the process was determined in real time and compared to surface properties, such as porosity and morphology. The light-scattering results were compared with measurements of skin-friction drag, static contact angle, and contact-angle hysteresis. The in situ, noninvasive optical technique was shown to correlate well with the more conventional methods for quantifying surface hydrophobicity, such as flow slip and contact angle. 相似文献
24.
Martha Kaddumukasa David Nsubuga Fredrick J. Muyodi 《Lakes & Reservoirs: Research and Management》2012,17(4):291-299
Vibrio cholerae, a bacterium that causes cholera, poses a human health risk when consumed via untreated or contaminated water. Monthly investigations into the presence of V. cholerae from Lakes Albert, George and Victoria were conducted, with the goal being to examine the relationship between the occurrences of V. cholerae with various water quality parameters at fish landing sites in major water bodies in Uganda. The pH, temperature and electrical conductivity were measured at three fishing sites in each of the three study lakes; namely Gabba in Lake Victoria, Butiaba in Lake Albert and Kayanzi in Lake George. The pH values varied from 7.76 to 9.36 at Butiaba, 8.68 to 9.85 at Kayanzi and 6.6 to 9.88 at Ggaba. The temperature ranged from 17.9 to 32.3 °C at Butiaba, 22.5 to 29 °C at Kayanzi and 18.2 to 30.5 °C at Ggaba. The electrical conductivity ranged from 129.2 to 984 μS cm?1 at Butiaba, 658 to 1090 μS cm?1 at Kayanzi and 119 to 218 μS cm?1 at Ggaba, for Lakes Albert, George and Victoria, respectively. Enrichment techniques were used to detect culturable V. cholerae on TCBS culture media. Seventy‐five (75%) of the samples (n = 90) were positive for V. cholera. The occurrence of V. cholerae was positively associated with water quality parameters over the 10‐month period of study. Vibrio cholerae was more frequently detected during the dry season (warmer) than during the wet season. These study results suggest the investigated study lakes are natural reservoirs for V. cholerae. 相似文献
25.
Lily L. Wang Terry C. Wallace Fredrick G. Hampel James H. Steele 《Metallurgical and Materials Transactions B》1996,27(3):433-443
A model based on the Hertz-Langmuir relation is used to describe how evaporation rates of the binary KCl-NaCl system change with time. The effective evaporation coefficient (α), which is a ratio of the actual evaporation rate to the theoretical maximum, was obtained for the KCl-NaCl system using this model. In the temperature range of 640 °C to 760 °C, the effective evaporation coefficient ranges from ~0.4 to 0.1 for evaporation experiments conducted at 0.13 Pa. At temperatures below the melting point, the lower evaporation coefficients are suggested to result from the more complex path that a molecule needs to follow before escaping to the gas phase. At the higher liquid temperatures, the decreasing evaporation coefficients result from a combination of the increasing vaporflow resistances and the heat-transfer effects at the evaporation surface and the condensate layer. The microanalysis of the condensate verified that composition of the condensate changes with time, consistent with the model calculation. The microstructural examination revealed that the vaporate may have condensed as a single solution phase, which upon cooling forms fine lamellar structures of the equilibrium KCl and NaCl phases. In conclusion, the optimum design of the evaporation process and equipment must take the mass and heat transfer factors and equipment materials issues into consideration. 相似文献
26.
The use of single- and multiple-word self-operated auditory prompting systems by five school-age workers with moderate mental retardation to independently transition between an ordered chain of tasks was examined in two vocational settings. The effectiveness of single- and multiple-word self-operated auditory prompts was assessed using an alternating treatment design within a multiple probe across settings. Analysis of the data revealed a significant effect on the number of independent task changes made by workers when using the single- or multiple-word auditory prompting system. When prompting systems were compared with one another, no significant differences were found in the number of independent task changes made by workers. Self-operated auditory prompts served as the stimulus control for desired behavior, they were effective for teaching workers with moderate mental retardation to manage their own task change behavior, and their use generalized across settings without additional training. 相似文献
27.
Previous research has shown that, without practice, users are slower using the foot than the hand to control input devices. This study compared the performance (before and after practice) of users operating a foot-controlled secondary input device (foot mouse) with the performance of users operating a hand-controlled secondary input device (hand trackball) to complete four word-processing tasks requiring various amounts of keyboard and secondary input device use. Before practice, hand trackball performance was better on all tasks. After practice, hand trackball performance was better on all tasks except the task requiring the greatest amount of keyboard use, for which there was no significant difference between devices. For all tasks, practice improved performance with the foot mouse but not with the hand trackball. These findings suggest that, with enough practice, it may be efficient for users to use a foot input device for tasks that also require keyboard input. 相似文献
28.
Glenn E. Gasner David Bigio Charles Marks Fredrick Magnus Christopher Kiehl 《Polymer Engineering and Science》1999,39(2):286-298
A series of experiments was conducted to determine what correlations exist between an experimental parameter, percent drag flow, and other parameters such as head, tail and mean residence time. Experimentation was carried out on two polymer systems, a model system of near-Newtonian fluid and a viscoelastic system of polyisoprene with several additives. To aid in the residence time analysis, data from three literature sources were cited and replotted. A family of residence time curves for a partially filled system can be combined into one curve by plotting the number of screw revolutions carrying the tracer to the extruder exit versus the percent drag flow. This method of plotting the data for each screw configuration estimates the mean residence time for any throughput and screw speed once a few data points are taken. In all four sets of experiments, the number of screw revolutions carrying the tracer to the exit decreases with increasing percent drag flow. The filled volume of the extruder was calculated from residence time data to show that percent drag flow is linearly related to extruder filled volume. When percent drag flow increased in the viscoelastic system the following results were recorded: fraction of polymer residence time spent in conveying elements increased, fraction of residence time spent in mixing elements decreased, polymer Mooney viscosity increased, number and weight average molecular weights increased and polydispersivity increased. 相似文献
29.
Fredrick O. Ochanda Mohamed A. Samaha Hooman Vahedi Tafreshi Gary C. Tepper Mohamed Gad‐el‐Hak 《应用聚合物科学杂志》2012,123(2):1112-1119
Mesh‐like fiber mats of polystyrene (PS) were deposited using DC‐biased AC‐electrospinning. Superhydrophobic surfaces with water contact angles greater than 150° and gas fraction values of up to 97% were obtained. Rheological study was conducted on these fiber surfaces and showed a decrease in shear stress when compared with a noncoated surface (no slip), making them excellent candidates for applications requiring the reduction of skin‐friction drag in submerged surfaces. We have also shown that addition of a second, low‐surface energy polymer to a solution of PS can be used to control the fiber internal porosity depending on the concentration of the second polymer. Contact‐angle measurements on mats consisting of porous and nonporous fibers have been used to evaluate the role of the larger spaces between the fibers and the pores on individual fibers on superhydrophobicity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
30.