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981.
Presented is a vocational reintegration concept for clients following craniocerebral trauma and other acquired brain damage. Close dovetailing of vocational and therapeutic measures is advocated, as it is mostly the neuropsychological disorders or problems in behaviour and emotional experience that stand in the way of returning to work. A work experience and adjustment setting holds particularly great potential for addressing these difficulties in a day-to-day life-related, remedial manner. Another focus is follow-up care of those clients who have returned to competitive employment. These clients are called on regularly at their workplace by programme vocational guidance/vocational assessment staff; necessary adaptations are carried out, difficulties dealt with, and possible solutions sought jointly with the employer. A catamnestic study was undertaken to verify how many of the clients included in the programme had achieved long-term resettlement. It was found that the great majority of those who had returned to their former job, have retained their employment some one to two years later, with most of them working at a lower level than before the event. Clients unable to return to their former employer had mostly been pensioned despite the presence of partial working capacity. 相似文献
982.
We present a combined theoretical and experimental study of the electronic and excitonic properties of GaAs-based V-grooved quantum wires as well as their dependence on external magnetic fields. We propose a numerical approach which allows us to compute electron and hole states, as well as their mutual correlation effects for realistic wire geometries. Our predictions for the optical spectra and their dependence on magnetic field are compared with several spectroscopical observations on samples grown by MBE on holographic patterns. The agreement is excellent, thus demonstrating the one-dimensional nature of the ground state exciton and the excitonic nature of the first-subband transitions in the presence of a magnetic field. 相似文献
983.
IE Goldberg GC Rossi SR Letchworth JP Mathis J Ryan-Moro L Leventhal W Su D Emmel EA Bolan GW Pasternak 《Canadian Metallurgical Quarterly》1998,286(2):1007-1013
The recently isolated peptides endomorphin-1 and endomorphin-2 have been suggested to be the endogenous ligands for the mu receptor. In traditional opioid receptor binding assays in mouse brain homogenates, both endomorphin-1 and endomorphin-2 competed both mu1 and mu2 receptor sites quite potently. Neither compound had appreciable affinity for either delta or kappa1 receptors, confirming an earlier report. However, the two endomorphins displayed reasonable affinities for kappa3 binding sites, with Ki values between 20 and 30 nM. Both endomorphins competed 3H-[D-Ala2, MePhe4,Gly(ol)5] enkephalin binding to MOR-1 receptors expressed in CHO cells with high affinity. In mouse brain homogenates 125I-endomorphin-1 and 125I-endomorphin-2 binding was selectively competed by mu ligands. 125I-Endomorphin-1 and 125I-endomorphin-2 also labeled MOR-1 receptors expressed in CHO cells with high affinity. Autoradiography of the two 125I-labeled endomorphins demonstrated regional patterns in the brain similar to those previously observed for mu drugs. Pharmacologically, the endomorphins were potent analgesics. Although they were equipotent supraspinally, endomorphin-1 was more potent spinally. Endomorphin analgesia was effectively blocked by naloxone, as well as the mu-selective antagonists beta-funaltrexamine and naloxonazine. In CXBK mice, which are insensitive to supraspinal morphine, neither endomorphin was active, consistent with a mu mechanism of action. Finally, the endomorphins inhibited gastrointestinal transit. In conclusion, these results support the mu selectivity of these agents. 相似文献
984.
IA Gómez de Segura R De Rossi M Santos J López San-Roman FJ Tendillo F San-Roman 《Canadian Metallurgical Quarterly》1998,27(4):384-391
Work-related respiratory symptoms, acute lung function changes and personal endotoxin exposure were studied in 61 workers from a potato processing plant. According to their job title mean endotoxin exposure level, workers were divided into low (AM = 21 EU/m3) and high (AM = 56 EU/m3) exposure categories. Shortness of breath and chest tightness during work were reported by 18% and 16% of the workers, respectively, mainly in the low endotoxin exposure category. A total of 148 across-shift lung function changes were measured during three consecutive afternoon shifts. The mean FEV1 and MMEF showed a decrease over the work shift, being largest on the first working day after a 3-day absence from work. Workers exposed to high endotoxin levels showed a larger across-shift decrease in lung function than workers exposed to low endotoxin exposures, the effect being most pronounced on the first day after a 3-day absence from work. At the start of the second work shift, FVC, FEV1 and MMEF were lower than at the start of the first work shift. This difference was larger for high exposed workers. High exposed workers with work-related respiratory symptoms showed an 8-10% across-shift change in FVC, FEV1 and MMEF We conclude that significant across-shift decreases in lung function of potato processing workers is related to endotoxin exposure levels above 53 EU/m3 over 8 hr. 相似文献
985.
986.
987.
We consider a point-to-point wireless transmission where link layer ARQ is used to counteract channel impairments. In particular, we refer, as an example, to a 3G cellular system, where a dedicated channel is used between a mobile terminal and its serving base station. Our aim is to find accurate and fast heuristics for the characterization of link layer and higher level (e.g., application level) packet delay. Existing methods to obtain such statistics are often based on recursive computations or large-sized matrix manipulations. For these reasons, they are too complex to be successfully applied in a mobile terminal due to memory, delay, and energy constraints. We first present an analytical framework to compute link-layer packet delivery delay statistics as a function of the packet error rate; then we extend the model in order to find the statistics related to higher level packets (i.e., to aggregates of link layer packets). Both in-order and out-of-order delivery of link-layer packets to higher levels are considered. The goodness of the channel model considered in the analysis is proved by means of accurate channel simulation results. The obtained statistics are then characterized by highlighting their properties as a function of the round-trip time and the error rate at the link layer. Finally, fast and accurate heuristics are derived directly from the analysis. These heuristics are very simple (piecewise linear functions), so they can be effectively used in a mobile terminal to obtain accurate delay statistics estimates with little computational effort. 相似文献
988.
A. Cividini A. Taliercio G. Sacchi Landriani R. Bellotti G. Ferrara P. Rossi 《Materials and Structures》1992,25(8):490-498
An apparatus specifically designed for static and cyclic testing of concrete and rock cylindrical samples is described. A particular characteristic of this equipment is the possibility of cyclic variation of the confining pressure, in addition to variation of the vertical load. The technical features of the apparatus are illustrated, as well as those of the instruments used for measuring and recording the variation of loads and displacements during the tests, up to the failure of the specimens. Comments are also presented on the devices controlling the variation of load with time and on the characteristics of the load histories adopted in an experimental research aimed at investigating the behaviour of concrete under repeated triaxial loads. 相似文献
989.
JM Nieminen S Flibotte A Galindo-Uribarri G Viesti GC Ball D Bazzacco M Cromaz de Angelis G De Graaf J De Poli M TE Drake D Fabris C Finck VP Janzen S Lunardi M Lunardon NH Medina G Maron CM Petrache DC Radford Rossi Alvarez C O Stezowski C Theisen JC Waddington D Ward JN Wilson 《Canadian Metallurgical Quarterly》1996,54(5):2764-2766
990.
R Roncone L Rossi E Muiere M Impallomeni M Matteucci R Giacomelli G Tonietti M Casacchia 《Canadian Metallurgical Quarterly》1998,33(9):451-461
The aim of the study was to evaluate in a heterogeneous. Italian sample (n = 340) the psychometric properties of the Italian version of the Family Assessment Device (FAD), a 60-item questionnaire assessing family functioning. The questionnaire was administered to psychiatric (n = 116), medical (n = 114) and non-clinical samples (n = 110). In a sample of 30 non-clinical subjects the temporal stability of the FAD was investigated. The results showed a good temporal stability for Problem Solving, General Functioning. Communication, and Affective Responsiveness scales, and a good internal reliability of the scale. Factor analysis of the Italian version provided discrepancies with the hypothesized structure of the instrument, leading to the identification of seven slightly different dimensions. The proposed seven-factor model of the instrument did not provide a good fit to our data. The results of our study suggest the need for a major improvement in the adaptation of the FAD in the Italian setting. 相似文献