Impulse control disorders in Parkinson's disease: decreased striatal dopamine transporter levels

Objective Impulse control disorders are commonly associated with dopaminergic therapy in Parkinson's disease (PD). PD patients with impulse control disorders demonstrate enhanced dopamine release to conditioned cues and a gambling task on [11C]raclopride positron emission tomography (PET) imaging and enhanced ventral striatal activity to reward on functional MRI. We compared PD patients with impulse control disorders and age-matched and gender-matched controls without impulse control disorders using [123I]FP-CIT (2β-carbomethoxy-3β-(4-iodophenyl)tropane) single photon emission computed tomography (SPECT), to assess striatal dopamine transporter (DAT) density. Methods The [123I]FP-CIT binding data in the striatum were compared between 15 PD patients with and 15 without impulse control disorders using independent t tests. Results Those with impulse control disorders showed significantly lower DAT binding in the right striatum with a trend in the left (right: F(1,24)=5.93, p=0.02; left: F(1,24)=3.75, p=0.07) compared to controls. Conclusions Our findings suggest that greater dopaminergic striatal activity in PD patients with impulse control disorders may be partly related to decreased uptake and clearance of dopamine from the synaptic cleft. Whether these findings are related to state or trait effects is not known. These findings dovetail with reports of lower DAT levels secondary to the effects of methamphetamine and alcohol. Although any regulation of DAT by antiparkinsonian medication appears to be modest, PD patients with impulse control disorders may be differentially sensitive to regulatory mechanisms of DAT expression by dopaminergic medications

Phonon-assisted relaxation between hole states in quantum dot molecules

We study theoretically phonon-assisted relaxation and inelastic tunneling of holes in a double quantum dot. We derive hole states and relaxation rates from kp Hamiltonians and show that there is a finite distance between the dots where lifetimes of hole states are very long which is related to vanishing tunnel coupling. We show also that the light hole admixture to hole states can considerably affect the hole relaxation rates even though its magnitude is very small

COMPARATIVE STUDIES ON KEY INDICATORS USED IN PERFORMANCE MEASUREMENT SYSTEM OF POLYTECHNICS’ ACADEMIC STAFF

Polytechnic Transformation Plan is launched to reinforce the role of polytechnics and technical education in Malaysia. The third thrust of the Plan puts forth the need to equip polytechnics’ teaching personnel and support staff with high skills and competency (MoHE, 2009). As a result, performance of teaching personnel needs to be evaluated to ensure the efficiency and effectiveness of teaching personnel in polytechnics and thus, it is crucial to assert the key indicators used. Based on the literature review, the tentative key indicators identified include, teaching and supervision, research and innovation, administrative tasks, professional activities and services to community. These key indicators are tested in polytechnic context on comparative basis between Northern and Central Region in Malaysia. Researchers employed hybrid/mixed method as the research approach for this study because the method elaborate or develop analysis by providing richer details, and initiate new line of thinking through attention to surprise and provide fresh sight. Amongst the six strategies introduced by Creswell (2003), concurrent embedded strategy is implemented to empirically test the research objective. The purpose of this strategy is to use quantitative data and results to assist in the interpretation of qualitative findings through triangulation. Researchers interviewed the Directors and/or Deputy Directors/Heads of Department of the polytechnic on face-to-face semi-structured basis. In addition, questionnaires developed are distributed to academic staff of the polytechnics to gather their perspective on the key indicators of academic Performance Measurement System. The data collected via interviews are transcribed and translated into English for data analysis process using thematic coding. Besides that, quantitative data are described and analysed using Statistical Package for the Social Science (SPSS) as a toolAcademic Staff, Performance Measurement System, Polytechnic, Key Indicators

Models of Impulsivity with a Focus on Waiting Impulsivity: Translational Potential for Neuropsychiatric Disorders.

Waiting impulsivity, also known as premature or anticipatory responding, is well established in preclinical studies through the 5-Choice Serial Reaction Time (5-CSRT) task. Waiting impulsivity is important in disorders of addiction. Preclinical studies suggest a role both as a predictor, and as a consequence, in disorders of addiction. Here we discuss the relationship between the preclinical 5-CSRT and translational fidelity in newly developed translational tasks. Preclinical and clinical literature relevant to premature responding and disorders of addiction are reviewed. Understanding which processes are critical to premature responding is important in understanding the nature of premature responding. Premature responding may also have overlaps with motivational processes, proactive response inhibition, tonic inhibitory processes, and delay discounting.Dr. Voon is a Wellcome Trust Fellow and supported by the Wellcome Trust (093705/Z/10/Z).This is the final published version. It first appeared at http://link.springer.com/article/10.1007%2Fs40429-014-0036-5

Cognitive biases in binge eating disorder: the hijacking of decision making.

Binge eating disorder (BED) is the most common of eating disorders and is characterized by excessive, out-of-control, rapid food intake. This review focuses on cognitive impairments in BED, which represent an endophenotype that mediates brain function and behavior. Here we focus on reviewing impulsivity, compulsivity, attentional biases to food cues, and executive function. Behavioral regulation in BED appears to be influenced by the context of motivationally salient food cues and the degree of obesity. Deficits in delay discounting and risk taking under ambiguity are impaired in obesity irrespective of BED status. However, in BED subjects with milder obesity, greater risk seeking under explicit probabilistic risk is observed to monetary rewards, whereas this shifts to risk aversion and enhanced delay discounting in more severe obesity. Relative to non-BED obese subjects, BED is characterized by enhanced behavioral inflexibility or compulsivity across multiple domains, with subjects selecting the same choices despite change in relevance (set shifting), being no longer rewarding (habit formation), or irrespective of outcome (perseveration). The context of food cues was associated with multiple attentional and early and late inhibitory impairments and enhanced memory bias, although BED patients also have generalized cognitive interference in working memory. These findings may help explain the phenotype of binge eating. Motivationally salient food cues provoke attentional and memory biases along with impairing response inhibitory processes. Those with BED are also more susceptible to cognitive interference and have impaired decisional impulsivity, with the tendency to inflexibly stick with the same choices irrespective of changes in context. These findings suggest critical cognitive domains that may guide therapeutic interventions.Dr. Voon is funded by the Wellcome Trust (093705/Z/10/Z)This is the final version of the article. It was first available from Oxford University Press via http://dx.doi.org/10.1017/S109285291500068

INVESTIGATING CRITICAL CHALLENGES FACED BY POLYTECHNICS: A COMPARATIVE STUDY

Mustapha (2001) advocated that Malaysia is short of skilled workers to meet the demands of economic growth (as cited in Jailani, Rashid, Wahid & Noraini; 2009). Thus, there is a need for vocational and technical education, particularly at post-secondary technician levels (Jailani et. al.; 2009) to meet the shortage. Despite the need, there are many challenges faced by polytechnics. This study intends to investigate the critical challenges faced by polytechnics in the Northern and Central Region of Malaysia on case study basis and to put forth recommendations for practical implementations. Based on the literature review, the tentative key critical challenges has been identified which are the employability of polytechnic graduates, collaboration of industry with practical knowledge, competent academic staff, adequate infrastructure/funding and resources, reputation and perception of institution, design and development of curriculum. Researchers used the concurrent embedded strategy in mixed research approach, where directors and/or deputy directors and/or head or department have been interviewed while academic staffs are surveyed using convenience sampling method. Questionnaires are distributed to triangulate the data from qualitative method. After that, researchers analyses the qualitative data using Nvivo as a tool based on thematic coding and quantitative data using Excel and SPSS software as analysis tools to perform descriptive analysisCritical Challenges, Polytechnic, Northern and Central

Factors stimulating corporate crime in Malaysia

Building on the perception of both existing and potential investors in Kuching, Sarawak, this study aims to identify the factors that appear to stimulate corporate crime activity in organizations. A survey was carried out by distributing questionnaires to both types of investors selected on randomly basis. The findings reveal that corporate crime activities are mostly due to inadequate cash security practices, inadequate supervision as well as a lack of internal auditing. To minimize the effects of corporate crime on investors and organizations, managers should pay extra attention to these factors. On the other hand, future research within the context of corporate crime may consider the extent to which organizational crime can affect the shareholder value creation of organizations.Corporate Crime; Internal Control