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981.
982.
983.
Developing brief measures of motivation to abstain from substance use that reliably predict treatment retention and outcome is a high priority in the addiction field. This study examined the psychometric properties of a contemplation ladder designed to assess readiness to abstain from alcohol and drug use respectively, on the basis of the contemplation ladder for smoking cessation developed by Biener and Abrams (1991). Participants were 394 substance-using male and female welfare recipients referred for treatment. The combined alcohol and other drug (AOD) ladder showed discriminant validity with demographic and health characteristics, convergent validity with conceptually related treatment motivation variables, concurrent validity with baseline AOD treatment and substance use variables, and predictive validity for participation in treatment services up to 1 month later and abstinence outcomes up to 1 year later. The AOD ladder showed predictive validity for those in drug-free treatment and no treatment at baseline but not for those in methadone maintenance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
984.
This preliminary study examined the effects of tobacco-free snuff (intervention, n = 52) compared with no snuff (control, n = 54) for reducing tobacco use among smokeless tobacco (ST) users not interested in quitting. Both groups received behavioral instructions, and intervention subjects received tobacco-free snuff for 8 weeks. Participants were required to reduce their intake by 50% during the first 4 weeks and by 75% during the subsequent 4 weeks. Follow-up occurred at 12 weeks. Significant reductions were observed from baseline to week 8 (end of treatment) for both treatment groups in the amount of ST use (tins/week and dips/day, p<.001); mean urinary cotinine (p<.001); and mean urinary total NNAL, a carcinogen biomarker (p<.001). At week 8 the intervention resulted in a lower mean total NNAL (p = .048). Compared with the control condition, the intervention resulted in a higher percentage of subjects achieving at least a 50% reduction in cotinine (p = .046) and total NNAL (p = .002) at the end of treatment, more quit attempts (p = .030), and a longer mean duration of abstinence (p = .013) through follow-up. An ST reduction intervention incorporating tobacco-free snuff could potentially reduce risk for ST-related disease beyond that achieved with no snuff by increasing the number of patients who achieve significant reductions in carcinogen exposure and, more important, by facilitating tobacco abstinence by increasing quit attempts and abstinence duration.  相似文献   
985.
986.
Rates of smoking among individuals with psychiatric conditions are much greater than those seen in the general population, yet little is known about the psychometric properties of commonly used instruments that assess smoking-related variables among smokers with psychiatric conditions. The present study examined the factor structure and psychometric characteristics of the Smoking Consequences Questionnaire-Adult (SCQ-A; Copeland, Brandon, & Quinn, 1995, Psychological Assessment, 7, 484-494) among smokers with psychiatric conditions. A confirmatory factor analysis of the instrument indicated that the factor structure derived by the instrument's authors provided an adequate fit to the data. In addition, many of the 10 subscales of the SCQ-A demonstrated adequate internal consistency as assessed by Cronbach's alpha as well as adequate test-retest reliability over the course of 1 week. Based on the data derived from this sample, the SCQ-A has adequate psychometric properties for applications involving smokers with psychiatric conditions.  相似文献   
987.
In a packet-switched network, the service provider can charge users a state-dependent price, which depends on the extent to which the network is congested. Alternatively, one can charge users a long-term average price, which is set based on expected demand and capacity availability, but independent of instantaneous network conditions. In this paper, we compare the benefits of different pricing schemes from the service provider, society, and consumer perspectives. Our results suggest that adopting state-dependent pricing improves both profit and total benefits to the society, but may be detrimental to consumer benefits.  相似文献   
988.
Parameters associated with an observed variation in CDM ESD waveforms are shown to be pogo pin diameter, pogo pin length, distance between ground plane (GP) and charge plate, verification module disk diameter, dielectric area, and GP size. The effects on resulting discharge waveforms and solutions for improvement of existing CDM standards will be discussed.  相似文献   
989.
The authors report a series of 6 experiments investigating crossmodal links between vision and touch in covert endogenous spatial attention. When participants were informed that visual and tactile targets were more likely on one side than the other, speeded discrimination responses (continuous vs. pulsed, Experiments 1 and 2; or up vs. down, Experiment 3) for targets in both modalities were significantly faster on the expected side, even though target modality was entirely unpredictable. When participants expected a target on a particular side in just one modality, corresponding shifts of covert attention also took place in the other modality, as evidenced by faster elevation judgments on that side (Experiment 4). Larger attentional effects were found when directing visual and tactile attention to the same position rather than to different positions (Experiment 5). A final study with crossed hands revealed that these visuotactile links in spatial attention apply to common positions in external space. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
990.
Safety-relevant parameters are hypothesized to be important to the maintenance of pathological anxiety. The authors examined the effects of safety information and safety cues on anxious responding to a repeated 35% CO? challenge in 31 patients with panic disorder. Patients were randomly assigned to one of three conditions: (a) safety information, (b) safety information plus a safety cue, or (c) no safety information. In the safety information group, patients received accurate information regarding the benign effects of the CO? challenge. In the combined group, patients also received a safety cue that is salient for many patients with panic disorder (i.e., access to an anxiolytic pill during the challenge). The experimental manipulations did not differentially affect anxious responding following an initial challenge. However, after access to the anxiolytic was removed and the challenge procedure was repeated, those in the safety information alone condition showed lower subjective anxiety compared to those in the combined safety information/safety cue group. Findings suggest that safety information facilitates extinction of anxiety but only in the absence of safety cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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