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1.
Negative consequences are an important component of the substance use change process, yet no standardized measure exists to assess consequences of use. This study evaluated the psychometric properties of the Inventory of Drug Use Consequences, a self-report measure assessing drinking and drug use consequences. Participants (N=252) were assessed at entry into outpatient substance abuse treatment. Items loaded strongly on 1 factor, and internal consistency of the total scale was high. Fifteen items with the highest correlations with the total scale were chosen to represent the construct. The shortened measure exhibited good internal consistency, convergent and discriminant validity, and detected change over time and may be the measure of substance use consequences that is lacking in the field. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Optimal control (OC) methodology is used to develop a control policy for a batch-operated solar sludge dryer with ventilation as the dominant control. Batch performance criteria and instantaneous optimization criteria are developed for two economic environments: quota limited and capital limited. The general formulation, as well as simplifications resulting from the multiplicative form of the evaporation (drying) rate model, are presented. The multiplicative form results in a single constant number, called here “control intensity,” which is used to guide the on-line control decisions. These decisions turn out to be independent of the dry solids content (DSC) of the sludge. Further simplification, by assuming a strictly constant weather, is used to demonstrate the general effects of the economic and physical (weather) environment on the solution.

The OC approach is used to address, via simulation under realistic weather conditions, several design, operation, and pricing problems. In particular, the following have been considered: sizing of the ventilation fans, determination of a fair fee for sludge disposal, finding the best final DSC, and evaluating the effect of the price of electricity. Regarding the particular location represented by the data, it has been shown that the installed capacity of the ventilation fans should be increased and that there seems to be sufficient economic incentive for solar drying.  相似文献   
3.
Six motion strategies for a Cartesian 4-degrees-of-freedom (4-DOF) biomass processing robot were developed. Each of the corresponding trajectories consists of more than 1300 three-dimensional coordinate points. The motion strategies were evaluated due to their efficiency to select the most promising one for being embedded into the control system of the robot. For evaluation, an algorithm was developed calculating different evaluation parameters such as total cycle time, covered distance and no-load time. The best strategy was able to perform the task within 23 h. The total covered distance within this time period amounts to 33 km. The efficiency of the motion strategy in terms of load- and no-load time phases was ε=57% and has to be enhanced during further research. By doubling maximum velocity to 60 m min−1 in longitudinal direction (x) and to 20 m min−1 in transverse direction (y) the total cycle time would be reduced additionally by maximum 20%.  相似文献   
4.
Oleaginous Scenedesmus sp. was cultivated phototrophically in an open pond for biofuels production. The culture was harvested and subsequently dewatered and dried. The chemical properties of the Scenedesmus sp. lipids were determined as per standard ASTM methods. Biodiesel was synthesized by in situ transesterification from dried biomass using microwave and sonication techniques with tungstated zirconia (WO3/ZrO2) as a solid acid catalyst. In situ transesterification allowed minimizing the requirement of solvents by merging the two steps (i.e. extraction of lipid and conversion to biodiesel) to a single step. The use of a solid catalyst effectively reduces the purification cost of biodiesel due to ease of separation and potential for reuse. The conversion of Scenedesmus sp. lipids to biodiesel was determined by GC. Box–Behnken design was used for optimization of the variables to optimize the biodiesel yield and conversion. The efficiency of the two processes was compared.  相似文献   
5.
This study tested the efficacy of behavioral treatments for alcohol use disorders (AUD) among men who have sex with men (MSM) and who are at risk for HIV transmission. HIV-negative MSM with current AUD (N = 198) were recruited, offered treatment focused on reducing drinking and HIV risk, and followed during treatment and 12 months posttreatment. Participants (n = 89) accepted treatment and were randomized to either 4 sessions of motivational interviewing (MI) or 12 sessions of combined MI and coping skills training (MI + CBT). Other participants (n = 109) declined treatment but were followed, forming a non-help-seeking group (NHS). MI yielded significantly better drinking outcomes during the 12-week treatment period than MI + CBT, but posttreatment outcomes were equivalent. NHS participants significantly reduced their drinking as well. Service delivery and treatment research implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
A visco-elastic-plastic mathematical model that also incorporates transformation plasticity has been used to determine the thermal stress and strain generation in quenched plates of various thicknesses. An increase in plate thickness produced an increase in the maximum amount of absolute strain introduced during the quench. This was associated with an increase in the residual strain at the end of a water quench, but the residual strain was reduced in the case of an oil quench. Former results were in agreement with the experimental data obtained from 20 and 40 mm thick specimens. In contrast, the level of residual absolute stress at specific points in water quenched plates fell as the thickness increased, mainly on account of the amount of stress-relaxation in the later stages of the cooling process, as the temperature in the interior of the thicker sections fell to ambient. This effect did not agree well with the experimental results and casts some doubt on the viscous flow data used at longer times and lower temperatures. The agreement between calculation and experiment was much better in the case of the oil quenched material.  相似文献   
7.
The Fcgamma receptor IIIb (FcgammaRIIIb) for the Fc domain of IgG is expressed exclusively on neutrophils. The FcgammaRIIIb bears allotypic polymorphisms referred to as NA1, NA2, and SH, which are known for their frequent involvement in alloimmune and autoimmune neutropenias as well as in transfusion reactions. The bactericidal capacity of isolated neutrophils is easily activatable, and activation results in self-desintegration, thus preventing storage of neutrophils. As a result, only freshly isolated granulocytes can be used for antibody screening, often making it impossible to use typed panel cells. To provide a readily available source of typed panel cells, we therefore established stable mammalian cells expressing recombinant NA1, NA2, and SH antigens. We isolated mRNA from typed neutrophils and then transcribed it in cDNA. The cDNA that codes for the different forms of the FcgammaRIIIb was amplified by polymerase chain reaction and was subsequently subcloned into the mammalian expression vector pcDNA3. Chinese hamster ovary (CHO) cells were transfected with allele-specific constructs, and stable cell lines expressing FcgammaRIIIb were selected by flow cytometry. Because human sera show high background fluorescence with transfectants in flow cytometry, the monoclonal antibody-specific isolation of granulocyte antigens (MAIGA) assay was performed. By MAIGA assay, we tested 14 well-characterized human alloantibodies directed against the antigens NA1, NA2, and SH; 5 FcgammaRIIIb-specific isoantibodies; and 12 FcgammaRIIIb-reactive autoantibodies. Except one NA1- and one SH-specific alloantibody, all other antibodies could be identified by the use of CHO transfectants. In contrast to neutrophils, fixed CHO cells can be stored at 4 degrees C for at least 4 weeks or stored frozen for a longer period. This longer shelf life of the transfected CHO cells compared with isolated neutrophils will simplify the detection of the clinically most important FcgammaRIIIb-reactive alloantibodies and autoantibodies.  相似文献   
8.
Technologies and building blocks for fast packet forwarding   总被引:6,自引:0,他引:6  
We provide a review of the state of the art and the future of packet processing and switching. The industry's response to the need for wire-speed packet processing devices whose function can be rapidly adapted to continuously changing standards and customer requirements is the concept of special programmable network processors. We discuss the prerequisites of processing tens to hundreds of millions of packets per second and indicate ways to achieve scalability through parallel packet processing. Tomorrow's switch fabrics, which will provide node-internal connectivity between the input and output ports of a router or switch, will have to sustain terabit-per-second throughput. After reviewing fundamental switching concepts, we discuss architectural and design issues that must be addressed to allow the evolution of packet switch fabrics to terabit-per-second throughput performance  相似文献   
9.
10.
Urges to use substances is an important construct in understanding the maintenance of substance use as well as relapse. There is a need to evaluate single instruments measuring global urges to use substances (including alcohol). The Obsessive Compulsive Drinking Scale (OCDS; R. F. Anton, D. H. Moak, & P. Latham, 1995) was revised and tested as a single measure of urges to use substances. Participants were 252 adults entering outpatient substance abuse treatment. Results suggest that the revised scale (OCDS-R) primarily assesses 1 global factor for urges to use substances. In addition, strong support was found for the reliability and concurrent validity of the OCDS-R, although results for its predictive validity were mixed. The OCDS-R is a brief, psychometrically sound self-report instrument that has applicability within clinical and research settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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