855 resultados para Voltammetric behaviors
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Objective Substance-related expectancies are associated with substance use and post-substance use thoughts, feelings and behaviours. The expectancies held by specific cultural or sub-cultural groups have rarely been investigated. This research maps expectancies specific to gay and other men who have sex with men (MSM) and their relationship with substance patterns and behaviours following use, including sexual practices (e.g., unprotected anal intercourse). This study describes the development of a measure of such beliefs for cannabis, the Cannabis Expectancy Questionnaire for Men who have Sex with Men (CEQ-MSM). Method Items selected through a focus group and interviews were piloted on 180 self-identified gay or other MSM via an online questionnaire. Results Factor analysis revealed six distinct substance reinforcement domains (“Enhanced sexual experience”, “Sexual negotiation”, “Cognitive impairment”, “Social and emotional facilitation”, “Enhanced sexual desire”, and “Sexual inhibition”). The scale was associated with consumption patterns of cannabis, and in a crucial test of discriminant validity not with the consumption of alcohol or stimulants. Conclusions The CEQ-MSM represents a reliable and valid measure of outcome expectancies, related to cannabis among MSM. Future applications of the CEQ-MSM in health promotion, clinical settings and research may contribute to reducing harm associated with substance use among MSM, including HIV transmission.
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Negative mood regulation (NMR) expectancies, stress, anxiety, depression and affect intensity were examined by means of self-report questionnaires in 158 volunteers, including 99 clients enrolled in addiction treatment programs. As expected, addicts reported significantly higher levels of stress, anxiety, depression and affect intensity and lower levels of NMR compared to non-addict controls. NMR was negatively correlated with stress, anxiety, depression and affect intensity. The findings indicate that mood self-regulation is impaired in addicts. Low NMR and high affect intensity may predispose to substance abuse and addiction, or alternatively may reflect chronic drug-induced affective dysregulation.
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Attachment, fear of intimacy and differentiation of self were examined by means of self-report questionnaires in 158 volunteers, including 99 clients enrolled in addiction treatment programs. As expected, clients (who were undergoing treatment for alcoholism, heroin addiction, amphetamine/cocaine addiction or cannabis abuse) reported higher levels of insecure attachment and fear of intimacy, and lower levels of secure attachment and differentiation of self, compared to controls. Insecure attachment, high fear of intimacy and low self-differentiation appear to characterize clients enrolled in addiction treatment programs. Such characteristics may reflect a predisposition to substance problems, an effect of chronic substance problems, or conceivably both.
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Business practices vary from one company to another and business practices often need to be changed due to changes of business environments. To satisfy different business practices, enterprise systems need to be customized. To keep up with ongoing business practice changes, enterprise systems need to be adapted. Because of rigidity and complexity, the customization and adaption of enterprise systems often takes excessive time with potential failures and budget shortfall. Moreover, enterprise systems often drag business behind because they cannot be rapidly adapted to support business practice changes. Extensive literature has addressed this issue by identifying success or failure factors, implementation approaches, and project management strategies. Those efforts were aimed at learning lessons from post implementation experiences to help future projects. This research looks into this issue from a different angle. It attempts to address this issue by delivering a systematic method for developing flexible enterprise systems which can be easily tailored for different business practices or rapidly adapted when business practices change. First, this research examines the role of system models in the context of enterprise system development; and the relationship of system models with software programs in the contexts of computer aided software engineering (CASE), model driven architecture (MDA) and workflow management system (WfMS). Then, by applying the analogical reasoning method, this research initiates a concept of model driven enterprise systems. The novelty of model driven enterprise systems is that it extracts system models from software programs and makes system models able to stay independent of software programs. In the paradigm of model driven enterprise systems, system models act as instructors to guide and control the behavior of software programs. Software programs function by interpreting instructions in system models. This mechanism exposes the opportunity to tailor such a system by changing system models. To make this true, system models should be represented in a language which can be easily understood by human beings and can also be effectively interpreted by computers. In this research, various semantic representations are investigated to support model driven enterprise systems. The significance of this research is 1) the transplantation of the successful structure for flexibility in modern machines and WfMS to enterprise systems; and 2) the advancement of MDA by extending the role of system models from guiding system development to controlling system behaviors. This research contributes to the area relevant to enterprise systems from three perspectives: 1) a new paradigm of enterprise systems, in which enterprise systems consist of two essential elements: system models and software programs. These two elements are loosely coupled and can exist independently; 2) semantic representations, which can effectively represent business entities, entity relationships, business logic and information processing logic in a semantic manner. Semantic representations are the key enabling techniques of model driven enterprise systems; and 3) a brand new role of system models; traditionally the role of system models is to guide developers to write system source code. This research promotes the role of system models to control the behaviors of enterprise.
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Abstract Background: The current obesity epidemic is thought to be partly driven by over-consumption of sugar-sweetened diets and soft drinks. Loss-of-control over eating and addiction to drugs of abuse share overlapping brain mechanisms including changes in motivational drive, such that stimuli that are often no longer ‘liked’ are still intensely ‘wanted’ [7,8]. The neurokinin 1 (NK1) receptor system has been implicated in both learned appetitive behaviors and addiction to alcohol and opioids; however, its role in natural reward seeking remains unknown. Methodology/Principal Findings: We sought to determine whether the NK1-receptor system plays a role in the reinforcing properties of sucrose using a novel selective and clinically safe NK1-receptor antagonist, ezlopitant (CJ-11,974), in three animal models of sucrose consumption and seeking. Furthermore, we compared the effect of ezlopitant on ethanol consumption and seeking in rodents. The NK1-receptor antagonist, ezlopitant decreased appetitive responding for sucrose more potently than for ethanol using an operant self-administration protocol without affecting general locomotor activity. To further evaluate the selectivity of the NK1-receptor antagonist in decreasing consumption of sweetened solutions, we compared the effects of ezlopitant on water, saccharin-, and sodium chloride (NaCl) solution consumption. Ezlopitant decreased intake of saccharin but had no effect on water or salty solution consumption. Conclusions/Significance: The present study indicates that the NK1-receptor may be a part of a common pathway regulating the self-administration, motivational and reinforcing aspects of sweetened solutions, regardless of caloric value, and those of substances of abuse. Additionally, these results indicate that the NK1-receptor system may serve as a therapeutic target for obesity induced by over-consumption of natural reinforcers.
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Alcohol use disorders (AUDs) are complex and developing effective treatments will require the combination of novel medications and cognitive behavioral therapy approaches. Epidemiological studies have shown there is a high correlation between alcohol consumption and tobacco use, and the prevalence of smoking in alcoholics is as high as 80% compared to about 30% for the general population. Both preclinical and clinical data provide evidence that nicotine administration increases alcohol intake and nonspecific nicotinic receptor antagonists reduce alcohol-mediated behaviors. As nicotine interacts specifically with the neuronal nicotinic acetylcholine receptor (nAChR) system, this suggests that nAChRs play an important role in the behavioral effects of alcohol. In this review, we discuss the importance of nAChRs for the treatment of AUDs and argue that the use of FDA approved nAChR ligands, such as varenicline and mecamylamine, approved as smoking cessation aids may prove to be valuable treatments for AUDs. We also address the importance of combining effective medications with behavioral therapy for the treatment of alcohol dependent individuals.
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BACKGROUND: There has been some difficulty getting standard laboratory rats to voluntarily consume large amounts of ethanol without the use of initiation procedures. It has previously been shown that standard laboratory rats will voluntarily consume high levels of ethanol if given intermittent-access to 20% ethanol in a 2-bottle-choice setting [Wise, Psychopharmacologia 29 (1973), 203]. In this study, we have further characterized this drinking model. METHODS: Ethanol-naïve Long-Evans rats were given intermittent-access to 20% ethanol (three 24-hour sessions per week). No sucrose fading was needed and water was always available ad libitum. Ethanol consumption, preference, and long-term drinking behaviors were investigated. Furthermore, to pharmacologically validate the intermittent-access 20% ethanol drinking paradigm, the efficacy of acamprosate and naltrexone in decreasing ethanol consumption were compared with those of groups given continuous-access to 10 or 20% ethanol, respectively. Additionally, ethanol consumption was investigated in Wistar and out-bred alcohol preferring (P) rats following intermittent-access to 20% ethanol. RESULTS: The intermittent-access 20% ethanol 2-bottle-choice drinking paradigm led standard laboratory rats to escalate their ethanol intake over the first 5 to 6 drinking sessions, reaching stable baseline consumption of high amounts of ethanol (Long-Evans: 5.1 +/- 0.6; Wistar: 5.8 +/- 0.8 g/kg/24 h, respectively). Furthermore, the cycles of excessive drinking and abstinence led to an increase in ethanol preference and increased efficacy of both acamprosate and naltrexone in Long-Evans rats. P-rats initiate drinking at a higher level than both Long-Evans and Wistar rats using the intermittent-access 20% ethanol paradigm and showed a trend toward a further escalation in ethanol intake over time (mean ethanol intake: 6.3 +/- 0.8 g/kg/24 h). CONCLUSION: Standard laboratory rats will voluntarily consume ethanol using the intermittent-access 20% ethanol drinking paradigm without the use of any initiation procedures. This model promises to be a valuable tool in the alcohol research field.
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Alcohol use disorders (AUDs) impact millions of individuals and there remain few effective treatment strategies. Despite evidence that neuronal nicotinic acetylcholine receptors (nAChRs) have a role in AUDs, it has not been established which subtypes of the nAChR are involved. Recent human genetic association studies have implicated the gene cluster CHRNA3-CHRNA5-CHRNB4 encoding the α3, α5, and β4 subunits of the nAChR in susceptibility to develop nicotine and alcohol dependence; however, their role in ethanol-mediated behaviors is unknown due to the lack of suitable and selective research tools. To determine the role of the α3, and β4 subunits of the nAChR in ethanol self-administration, we developed and characterized high-affinity partial agonists at α3β4 nAChRs, CP-601932, and PF-4575180. Both CP-601932 and PF-4575180 selectively decrease ethanol but not sucrose consumption and operant self-administration following long-term exposure. We show that the functional potencies of CP-601932 and PF-4575180 at α3β4 nAChRs correlate with their unbound rat brain concentrations, suggesting that the effects on ethanol self-administration are mediated via interaction with α3β4 nAChRs. Also varenicline, an approved smoking cessation aid previously shown to decrease ethanol consumption and seeking in rats and mice, reduces ethanol intake at unbound brain concentrations that allow functional interactions with α3β4 nAChRs. Furthermore, the selective α4β2(*) nAChR antagonist, DHβE, did not reduce ethanol intake. Together, these data provide further support for the human genetic association studies, implicating CHRNA3 and CHRNB4 genes in ethanol-mediated behaviors. CP-601932 has been shown to be safe in humans and may represent a potential novel treatment for AUDs.
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Abstract Alcohol dependence is a disease that impacts millions of individuals worldwide. There has been some progress with pharmacotherapy for alcohol-dependent individuals; however, there remains a critical need for the development of novel and additional therapeutic approaches. Alcohol and nicotine are commonly abused together, and there is evidence that neuronal nicotinic acetylcholine receptors (nAChRs) play a role in both alcohol and nicotine dependence. Varenicline, a partial agonist at the alpha4beta2 nAChRs, reduces nicotine intake and was recently approved as a smoking cessation aid. We have investigated the role of varenicline in the modulation of ethanol consumption and seeking using three different animal models of drinking. We show that acute administration of varenicline, in doses reported to reduce nicotine reward, selectively reduced ethanol but not sucrose seeking using an operant self-administration drinking paradigm and also decreased voluntary ethanol but not water consumption in animals chronically exposed to ethanol for 2 months before varenicline treatment. Furthermore, chronic varenicline administration decreased ethanol consumption, which did not result in a rebound increase in ethanol intake when the varenicline was no longer administered. The data suggest that the alpha4beta2 nAChRs may play a role in ethanol-seeking behaviors in animals chronically exposed to ethanol. The selectivity of varenicline in decreasing ethanol consumption combined with its reported safety profile and mild side effects in humans suggest that varenicline may prove to be a treatment for alcohol dependence.
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Abstract RATIONALE: Previous studies have shown that orexin-1/hypocretin-1 receptors play a role in self-administration and cue-induced reinstatement of food, drug, and ethanol seeking. In the current study, we examined the role of orexin-1/hypocretin-1 receptors in operant self-administration of ethanol and sucrose and in yohimbine-induced reinstatement of ethanol and sucrose seeking. MATERIALS AND METHODS: Rats were trained to self-administer either 10% ethanol or 5% sucrose (30 min/day). The orexin-1 receptor antagonist SB334867 (0, 5, 10, 15, 20 mg/kg, i.p.) was administered 30 min before the operant self-administration sessions. After these experiments, the operant self-administration behaviors were extinguished in both the ethanol and sucrose-trained rats. Upon reaching extinction criteria, SB334867 (0, 5, 10 mg/kg, i.p.) was administered 30 min before yohimbine (0 or 2 mg/kg, i.p.). In a separate experiment, the effect of SB334867 (0, 15, or 20 mg/kg, i.p.) on general locomotor activity was determined using the open-field test. RESULTS: The orexin-1 receptor antagonist, SB334867 (10, 15 and 20 mg/kg) decreased operant self-administration of 10% ethanol but not 5% sucrose self-administration. Furthermore, SB334867 (5 and 10 mg/kg) significantly decreased yohimbine-induced reinstatement of both ethanol and sucrose seeking. SB334867 did not significantly affect locomotor activity measured using the open-field test. CONCLUSIONS: The results suggest that inhibition of OX-1/Hcrt-1 receptors modulates operant ethanol self-administration and also plays a significant role in yohimbine-induced reinstatement of both ethanol and sucrose seeking in rats.
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Evidence suggests that both start-up and young firms (henceforth: new firms) – despite typically being resource-constrained – are sometimes able to innovate (Katila & Shane 2005). Such firms are seldom able to invest in expensive innovation processes, which suggests that they may rely on other pathways to innovation. In this paper, we test arguments that “bricolage,” defined as making do by applying combinations of the resources at hand to new problems and opportunities, provides a pathway to innovation for new firms. Our results suggest that variations in bricolage behaviors can provide an explanation of innovation under resource constraints by new firms.
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The importance of innovation to the long-term survival and growth of an organization has been well recognized and acknowledged, and HRM practitioners face a critical challenge to design and implement practices that ensure the behaviors and attitudes necessary for sustained innovation. In this paper, we present the findings from an exploratory study that establish initial indications of links between work design, training and dcvelopment, employee engagement, and innovative work behaviors, setting the agenda for lurther investigation of how spccific HR practices of work design and training and development can supp0l1 employee engagement, and facilitate sustained innovation.
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Objective Harassment from motorists is a major constraint on cycling that has been under-researched. We examined incidence and correlates of harassment of cyclists. Methods Cyclists in Queensland, Australia were surveyed in 2009 about their experiences of harassment while cycling, from motor vehicle occupants. Respondents also indicated the forms of harassment they experienced. Logistic regression modeling was used to examine gender and other correlates of harassment. Results Of 1830 respondents, 76% of men and 72% of women reported harassment in the previous 12 months. The most reported forms of harassment were driving too close (66%), shouting abuse (63%), and making obscene gestures/sexual harassment (45%). Older age, overweight/obesity, less cycling experience (< 2 years) and less frequent cycling (< 3 days/week) were associated with less likelihood of harassment, while living in highly advantaged areas (SEIFA deciles 8 or 9), cycling for recreation, and cycling for competition were associated with increased likelihood of harassment. Gender was not associated with reports of harassment. Conclusions Efforts to decrease harassment should include a closer examination of the circumstances that give rise to harassment, as well as fostering road environments and driver attitudes and behaviors that recognize that cyclists are legitimate road users.