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61.
The authors assessed the joint perceptions of the employee and his or her employer to examine mutuality and reciprocity in the employment relationship. Paired psychological contract reports were obtained from 80 employee-employer dyads in 16 university-based research centers. On the basis of in-depth study of the research setting, research directors were identified as primary agents for the university (employer) in shaping the terms of employment of staff scientists (employees). By assessing the extent of consistency between employee and employer beliefs regarding their exchange agreement, the present study mapped the variation and consequences of mutuality and reciprocity in psychological contracts. Results indicate that both mutuality and reciprocity are positively related to archival indicators of research productivity and career advancement, in addition to self-reported measures of Met Expectations and intention to continue working with the employer. Implications for psychological contract theory are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Hope is recognized as one of four key factors contributing to psychotherapeutic change across a variety theoretical approaches (Hubble, Duncan, & Miller, 1999), especially early in the psychotherapeutic sequence. To date little research has looked at how hope is translated into specific practices by psychotherapists during psychotherapy sessions. This case study employed basic interpretive inquiry (Merriam, 1998) to explore the hope-focused practices of five hope-educated psychotherapists with 11 clients early in the therapy sequence. Two categories characterize the overall findings, that is, implicit and explicit hope-focused practices. This first paper in a two-part research report focuses on implicit hope-focused interventions. Implicit hope-focused interventions were those practices identified by therapists as addressing client hope without employing the word hope explicitly. Implicit hope practices addressed two key aspects of therapy, (a) attending to therapeutic relationship, and (b) fostering client perspective change. The second paper in this series examines findings regarding explicit hope-focused interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
Doxorubicin (doxo) remains the standard of care for patients with advanced soft tissue sarcoma (STS), even though response rates to doxo are only around 14% to 18%. We evaluated enapotamab vedotin (EnaV), an AXL-specific antibody-drug conjugate (ADC), in a panel of STS patient-derived xenografts (PDX). Eight models representing multiple STS subtypes were selected from our STS PDX platform (n = 45) by AXL immunostaining on archived passages. Models were expanded by unilateral transplantation of tumor tissue into the left flank of 20 NMRI nu/nu mice. Once tumors were established, mice were randomized into an EnaV treatment group, or a group treated with isotype control ADC. Treatment efficacy was assessed by tumor volume evaluation, survival analysis, and histological evaluation of tumors, and associated with AXL expression. EnaV demonstrated significant tumor growth delay, regression, and/or prolonged survival compared to isotype control ADC in 5/8 STS PDX models investigated. Experimental passages of responding models were all found positive for AXL at varying levels, but no linear relationship could be identified between the level of expression and level of response to EnaV. One model was found negative for AXL on experimental passage and did not respond to EnaV. This study provides a preclinical rationale for the evaluation of AXL-targeting ADCs in the treatment of AXL-expressing sarcomas.  相似文献   
64.
Infrared brightness temperature (BT) measurements obtained from the UK Meteorological Research Flight C-130 Hercules aircraft, spatially coincident and near contemporaneous with ERS-1 Along Track Scanning Radiometer (ATSR) and NOAA-14 Advanced Very High Resolution Radiometer (AVHRR), are presented. These data have been used to obtain much needed on-going validation of the ERS-1 ATSR prior to the de-commissioning of the ATSR instrument in March 1997. BT comparisons between the ATSR and AVHRR nadir channels show negligible differences of 0.3 deg K, indicating that both radiometers are well calibrated. However, significant differences are found when common sea surface temperature (SST) algorithms are applied to the BT data. The original dual view ERS-1 ATSR skin SST (SSST) algorithm has a 0.6K cool bias relative to the in situ observations, which is consistent with other in situ validation studies. New SSST coefficients derived using the same atmospheric transmission model show that, when the appropriate pixel noise contribution is considered in the algorithm derivation, substantially improved SSST is derived from the ERS-1 ATSR. Comparing the NOAA-14 AVHRR non-linear SST (NLSST) and multi-channel SST (MCSST) algorithms to the aircraft data, the non-linear nature of the NLSST algorithm results in a small bias of 0.3 deg K compared to a substantial cool bias of 1 deg K in the MCSST case. This result highlights deficiencies in the MCSST.  相似文献   
65.
Web mapping has become a popular way of distributing interactive digital maps over the internet. Instead of dynamically generating map images on the fly, those can be pre-generated and served from a server-side cache for faster retrieval. However, these caches can grow unmanageably in size when the cartography covers mid to large areas for multiple rendering scales. This forces modest organizations to use partial caches containing just a subset of the total tiles, and makes their services less attractive than other mapping services like Google Maps or Microsoft Bing Maps. This work proposes a neural-network-based intelligent system that predicts which areas are likely to be requested in the future from a catalog of geographic features and a short history of past requests. These priority regions can be used by a tile prefetching policy to achieve an optimal population of the cache. Neural networks are trained and validated using supervised learning with real data-sets from a public nation-wide web map service. Trace-driven simulations demonstrate that accurate long-term predictions, up to 90% in terms of cache-hit ratio, can be obtained with the proposed model by prefetching a low fraction, only the 20% of the total tiles, and with a short training period.  相似文献   
66.
A method is proposed to be used as the first step in the ontology acquisition process. This method is based on the use of concept maps as a means of expression for the expert, followed by an application that assists the expert in detailing the structure of the knowledge represented in the map. This application analyses the concept map, taking into account the map topology and key words used by the expert. From this analysis a series of questions are presented to the expert that, when answered, reduce the map ambiguity and identify some common patterns in ontological representations, such as generalizations and mereologic relations. This information can be used by the knowledge engineer during further knowledge acquisition sessions or to direct the expert to a further improvement of the map. The method was tested by a group of volunteers, most of them engineers working at the aerospace sector, and the results suggest that both the use of concept mapping as well as the refining step are acceptable from the point of view of the end user, supporting the claim that this method is viable as an option to reduce some of the difficulties in large scale ontology construction.  相似文献   
67.
Researchers often have expectations about the research outcomes in regard to inequality constraints between, e.g., group means. Consider the example of researchers who investigated the effects of inducing a negative emotional state in aggressive boys. It was expected that highly aggressive boys would, on average, score higher on aggressive responses toward other peers than moderately aggressive boys, who would in turn score higher than nonaggressive boys. In most cases, null hypothesis testing is used to evaluate such hypotheses. We show, however, that hypotheses formulated using inequality constraints between the group means are generally not evaluated properly. The wrong hypotheses are tested, i.e.. the null hypothesis that group means are equal. In this article, we propose an innovative solution to these above-mentioned issues using Bayesian model selection, which we illustrate using a case study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
68.
We studied the dimensional nature of same–different discrimination behavior in pigeons. Birds first learned to discriminate between simultaneously presented displays of 16 identical items (Same arrays) and 16 nonidentical items (Different arrays), conditional on the color of the background. After discrimination mastery, we tested the birds with Mixture arrays comprising both identical and nonidentical items. Accuracy increased and reaction time decreased as the disparity in entropy (a measure of variability) between the arrays increased. As well, within each entropy disparity level, lower entropy values were more discriminable than higher entropy values. These results accord with a logarithmic relation between entropy and discriminative behavior and, thus, with the idea that the discrimination of Same from Different arrays follows Weber's Law. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
69.
Although survey results seem to indicate an abundant interest among Canadian psychology graduate students in pursuing training in criminal justice psychology, the recruitment and retention of psychologists in the Correctional Service of Canada (CSC) has been of some concern. The present study is a 2008 survey of sites within CSC that provide opportunities for clinical psychology training with offender clientele. Survey findings demonstrated that a broad range of clinical psychology training opportunities were available across 16 sites. The most frequently cited barrier to providing training was lack of time by prospective trainers, and sites reported retaining relatively few of their trainees for subsequent psychologist positions. Information was also obtained regarding vacant psychologist positions across CSC regions. In light of survey findings, substantive discussion is devoted toward the issues of psychologist recruitment and retention in Canadian federal corrections, including a discussion of both potential and existing training initiatives. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
70.
The results of a complex investigation into dark-current relaxation in the long-time region of an MIM structure based on an As-Se thin-film chalcogenide system are presented. The values of parameters describing the electronic processes ocurring in the contact layers of the investigated compounds are estimated. The coincidence of the nature of conductivity and charge-accumulation mechanisms is revealed. The relaxation-time distribution function is calculated, and its structural sensitivity to such technological factors as the change in the composition stoichiometry and the method for manufacturing experimental samples is established.  相似文献   
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