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141.
Comments on the differences in stipends, supervision, number of days allotted for leave, titles, and others items related to clinical internships at various training sites and suggests that the establishment of minimum national standards for approved sites should be considered by the Association of Psychology Internship Centers and the American Psychological Association. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
142.
Administered training to Ss at varying levels of cognitive organization. Ss were 60 middle-class Israeli 6-7 yr olds. The training condition exploited structural mix between operational length and intuitive speed concepts, such that Ss successively alternated partial structures underlying these concepts. Findings were that (a) training was effective for operational speed concept acquisition among Ss with structural mix; (b) training was not effective for Ss without structural mix; (c) those who acquired the operational speed concept also acquired operational reasoning for the concept of movement; and (d) all Ss who employed an integration strategy during training became operational for speed on the posttest, while none who used other strategies acquired operational reasoning for the speed concept. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
143.
Average rates of polypeptide chain elongation have been determined in cockerel liver explants on 4 successive days following an in vivo injection of 17 beta-estradiol. Incorporation of [3H]leucine by the explants is linear for at least 24 h, and the rate of protein synthesis increases significantly after estrogen injection. The explants synthesize and secrete serum albumin. B-apolipoprotein, and the phosphoprotein vitellogenin at relative rates which are similar to those reported for liver in vivo. Using this system, changes in the average rates of polypeptide chain elongation have been analyzed as a temporal sequence following a single injection of 17 beta-estradiol into cockerels. For this, average ribosome half-transit times were determined by measuring the kinetics of transfer of labeled polypeptides from polysomal-bound to released polypeptides. The data revealed a dramatic effect of estradiol on the average ribosome half-transit time with a maximum increase of 4.6-fold; however, the average size of polypeptides synthesized by explants at the peak of induction increased only 15% when compared to uninduced liver explants. These findings indicate that injection of estradiol results in large changes in the actual rates at which amino acids are added to the growing nascent polypeptide chain; that is, rates of polypeptide chain elongation. Therefore, translation-level regulation of protein synthesis in cockerel livers plays a significant part in determining the magnitude of the response to hormone stimulation.  相似文献   
144.
O?2 radicals were formed in the presence of 2,5- dimethyl benzoquinone (DMBQ). The equilibrium constant of the electron transfer reaction DMBQ + O?2 ? DMBQ? + O2 was determined. From this value and from E0(DMBQ/DMBQ?) we calculated the redox potential of the couple O2/O?2, as E0 (O2/O?2) = ?0.33 V.  相似文献   
145.
A general model for multiattribute Bayesian acceptance sampling plans is developed which incorporates the multiattribute utility function of a decision maker in its design. The model accommodates various dispositions of rejected lots such as screening and scrapping. The disposition of rejected lots is shown to have a substantial impact on the solution approach used and on the ease of incorporation of multiattribute utility functions in terms of their measurement complexity, functional form, and parameter estimation. For example, if all attributes are screenable upon rejection, and the prior distributions of lot quality on each attribute are independent, then an optimal multiattribute sampling plan can be obtained simply by solving for an optimal single sampling plan on each attribute independently. A discrete search algorithm, based on pattern search, is also developed and shown to be very effective in obtaining an optimal multiattribute inspection plan when such separability cannot be accomplished.  相似文献   
146.
The structure of potato protein precipitates formed by heat treatment or acidification of potato juice was investigated by transmission electron microscopy. Precipitates formed by heat denaturation (3 min at 100°C) consist of electron-dense particles of diameter < 300 nm, aggregated into three-dimensional open networks. Precipitates, formed by acidification to pH 3.0 and holding the acidified juice at room temperature, consist of network-like aggregates of electron-dense particles embedded in thin films which hinder the formation of a dense sediment. This structure explains the high sediment volumes which are typical of this kind of precipitate. By warming the acidified potato juice to 40°C, rapid flocculation and sedimentation of the suspended insoluble protein are observed within a few minutes and a dense sediment is finally obtained. This sediment consists mainly of the network-like aggregates of electron-dense particles and material of low electron density formed by the collapse of the films. Protein films have also been observed in precipitates of heat-denatured bovine serum albumin (BSA). High-methoxyl pectin promotes the formation of protein films on heat denaturation of potato proteins or BSA.  相似文献   
147.
The relationship between the product specifications and its economic value for the manufacturer and the customer is analyzed. The aspects of the product dealt with are cost performance and its implications for pricing policy. An economic model for the manufacturer is combined with a cost/benefit analysis for the prospective customer to yield an integrative model that permits coupling of the demand and supply functions under the common denominator of performance level. It allows the manufacturer to weigh the performance attributes of the product by means of the customer evaluation and attenuates the tendency to overspecify the product. A numerical example based on data gathered on a citrus-fruit sorting robot is given. In this example the profitability frontier, where both parties make profits, is defined and calculated  相似文献   
148.
A new oxidative method of preparation of the chromium dioxide from Cr2O3is described. For the improvement of magnetic properties, in particular coercive field, of such a ferromagnetic oxide a substitution by rhodium +IV leads to the new interesting material Cr1-xRhxO2with needlike particles (H_{c} simeq 500Oe).  相似文献   
149.
A general paradigm for recognizing 3D objects is offered, and applied to some geometric primitives (spheres, cylinders, cones, and tori). The assumption is that a curve on the surface, or a pair of intersecting curves, was measured with high accuracy (for instance, by a sensory robot). Differential invariants of the curve(s) are then used to recognize the surface. The motivation is twofold: the output of some devices is not surface range data, but such curves. Also, a considerable speedup is obtained by using curve data, as opposed to surface data which usually contains a much higher number of points.We survey global, algebraic methods for recognizing surfaces, and point out their limitations. After introducing some notions from differential geometry and elimination theory, the differential and semi-differential approaches to the problem are described, and novel invariants which are based on the curve's curvature and torsion are derived.  相似文献   
150.
Scent has been well documented as having significant effects on emotion (Alaoui-Ismaili in Physiol Behav 62(4):713–720, 1997; Herz et al. in Motiv Emot 28(4):363–383, 2004), learning (Smith et al. in Percept Mot Skills 74(2):339–343, 1992; Morgan in Percept Mot Skills 83(3)(2):1227–1234, 1996), memory (Herz in Am J Psychol 110(4):489–505, 1997) and task performance (Barker et al. in Percept Mot Skills 97(3)(1):1007–1010, 2003). This paper describes an experiment in which environmentally appropriate scent was presented as an additional sensory modality consistent with other aspects of a virtual environment called DarkCon. Subjects’ game play habits were recorded as an additional factor for analysis. Subjects were randomly assigned to receive scent during the VE, and/or afterward during a task of recall of the environment. It was hypothesized that scent presentation during the VE would significantly improve recall, and that subjects who were presented with scent during the recall task, in addition to experiencing the scented VE, would perform the best on the recall task. Skin-conductance was a significant predictor of recall, over and above experimental groups. Finally, it was hypothesized that subjects’ game play habits would affect both their behavior in and recall of the environment. Results are encouraging to the use of scent in virtual environments, and directions for future research are discussed. The project described herein has been sponsored by the US Army Research, Development, and Engineering Command (RDECOM). Statements and opinions expressed do not necessarily reflect the position or the policy of the US Government; no official endorsement should be inferred.  相似文献   
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