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1.
Literature suggests that a complex and often hostile relationship exists between the science and practice of clinical psychology. Contributors to this conflict of viewpoints are reconsidered within the proposition that there are different roads to discovery and that there may be good reasons to keep the science and practice of clinical psychology somewhat separate. Results of a national survey of 325 psychologists are reviewed that support the view that psychological practitioners value research and consider their practices to be augmented by scientific findings. However, they are in need of vehicles of communication that will help them translate scientific findings into practice. Results suggest that practitioners do more to understand scientific findings than scientists do to understand the problems that face clinical practitioners. Ways to facilitate communication between and among these groups are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Abstract: This paper examines the first stage of using genetic algorithms in design—how to encode designs as chromosomes. Generic representations capable of describing the geometry of any solid object to eliminate the unnecessary duplication of work at this stage are explored. A suitable low-parameter, spatial-partitioning representation is then proposed, using partitions consisting of six-sided polyhedra intersected by planes. Finally, the coding of the representation is examined, with the conclusion that allelic coding with control genes and user-definable, fixed-value alleles would provide the most flexible system.  相似文献   
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The mast cell response in skin and lymph nodes was examined during the sensitization phase of dinitrofluorobenzene (DNFB)-induced contact hypersensitivity in mice. Degranulation of 62% of mast cells in DNFB-exposed skin was evident within 30 min of a dual application of DNFB, reaching a peak of 77% at 24 h, and persisting in 42% after 5 d. Abundant expression of macrophage inflammatory protein (MIP)-1alpha and MIP-1beta mRNAs and proteins was observed in keratinocytes, and mast cell degranulation was significantly inhibited after administration of neutralizing antibodies to MIP-1alpha, but not MIP-1beta. During DNFB sensitization, the mast cell density in the skin decreased by half, concurrent with a fivefold expansion of mast cell numbers in draining lymph nodes. Fluorescent-labeled mast cells injected into the skin appeared in draining lymph nodes after application of DNFB, followed by subsequent migration to the spleen. In lymph nodes, mast cells were an abundant and predominant source of MIP-1beta, neutralization of which partially inhibited T lymphocyte recruitment. These results indicate that mast cells contribute to the induction of this primary immune response by activation at and migration from the site of antigen encounter to draining lymph nodes, wherein they mediate T lymphocyte recruitment by production of MIP-1beta.  相似文献   
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Plasma samples from two experiments were processed to determine whether ergot alkaloids associated with endophyte-infected tall fescue altered peripheral thyroxine (T4), triiodothyronine (T3), or cortisol concentrations in cattle. In Exp. 1, seven Angus steers (294 kg) received i.v. bolus injections of saline (SAL), ergonovine maleate (7 mg; EM), or ergotamine tartrate (7 mg; ET) at weekly intervals, and they received all treatments during the study. Blood was sampled every 15 min for 5 h, and treatments were given after h 1. Mean ambient temperature was 34 degrees C. Treatment x time affected plasma concentrations of T3 (P < .05) and of cortisol (P < .001) but not that of T4 (P > .2). Plasma T3 concentrations were not affected by SAL, whereas concentrations increased (P < .01) after either EM or ET treatment. Plasma cortisol concentrations were not altered by SAL or EM, but they were increased (P < .001) by ET treatment. In Exp. 2, six Holstein cows (499 kg) nursing calves received a bolus i.v. injection of SAL, EM (9.5 mg), or ET (9.5 mg) per estrous cycle, and all treatments were given over three cycles. Blood was sampled every 20 min for 5 h; treatments were given after h 1. Mean ambient temperature was 26 degrees C. Treatment x time affected T3 (P = .08) and cortisol (P < .001) and tended to influence (P = .16) T4 concentrations. Plasma T3, T4, and cortisol concentrations were not influenced by SAL treatment. Plasma T3 was higher (P < or = .01) after EM or ET treatment compared with pretreatment concentrations. Concentrations of T4 during the 4 h after EM and ET were increased (P < .001) compared with pretreatment. Plasma cortisol concentrations were not altered by EM but were increased (P < .001) by ET. Ergot alkaloids implicated as contributing agents to fescue toxicosis alter plasma concentrations of hormones important to metabolic and thermoregulatory functions in cattle.  相似文献   
5.
This paper is the final in a series of three viscosity and density studies of pure n-alkanes and selected binary and quaternary mixtures. A standard U-tube viscometer was used for viscosity measurements, and a Pyrex flask-type pycnometer was used for density determinations. Results are given here for pure alkane and selected binary mixtures of n-tetradecane + n-octane, for selected quaternary mixtures of n-hexadecane + n-dodecane + n-decane + n-hexane, and for pure and selected quaternary mixtures of n-hexadecane + n-dodecane + n-nonane + n-heptane at 303.16 and 308.16 K. The principle of congruence was tested, as was the Grunberg and Nissan equation, as they have been shown to be useful as prediction techniques for other n-alkane binary mixtures. Comparisons were made between the two groups of quaternary alkane mixtures and the binary n-tetradecane + n-octane mixtures of the same pseudo composition to understand better the dependence of mixture viscosities on the composition parameter.  相似文献   
6.
Binaural displays for immersive listening must model realistic acoustic environments, multiple sound sources, and accommodate source and head motion. Many displays accomplish this by convolving collections of spatially distributed point sources with head-related transfer functions (HRTFs). The computational load of such a system scales linearly with the number of HRTFs modeled by the display. Realistic scenes often require a large number of HRTFs, and this framework is computationally burdensome. We propose a method that significantly eases this load by formulating the HRTF filter array as a state-space system. Three state-space architectures are explored. The performance of the most general architecture is found to suffer due to the interaural time delay (ITD). This problem may be circumvented with two alternative architectures, although the ideal choice depends on the specific display application. For each architecture, two order-reduction techniques are explored. Both techniques are based on the Hankel operator; one is ad hoc and simple to implement whereas the other is optimal in the Hankel norm. The two methods yield similar auditory performance, although the optimal method may be desirable for HRTF approximation.  相似文献   
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Optical bench incorporating a photo-electric exposure meter and tricolour filters for measuring the blue, green, and red light transmissions of colour negatives. The instrument can be applied to both tricolour and white-light printing systems.  相似文献   
10.
Interactive graphic cad for tension structures   总被引:2,自引:0,他引:2  
This paper reviews the development and application of an interactive CAD system for the form-finding, load analysis and patterning of tensile coated fabric membrane structures. Particular emphasis is given to the integration of all design aspects ranging from form visualization to the production of fabrication patterns within the single CAD system.  相似文献   
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