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1.
Neurogenetic models predict neuropsychological weaknesses in the relatives of children with attention-deficit/ hyperactivity disorder (ADHD). The authors examined executive and regulatory measures in 386 relatives (307 parents, 79 siblings) of children with ADHD combined type, ADHD inattentive type, and controls. Predicted deficits were seen on trailmaking (relatives of ADHD combined type only), stop-signal reaction times (relatives of girls only), and response variability (mothers only) but not on naming or output speed. Effects generally held, even with relatives' ADHD status controlled. A neuropsychologically impaired subgroup of children with ADHD had relatives with clear neuropsychological weaknesses. The authors conclude that a neurogenetic model of ADHD etiology is supportable only for a subset of executive functions and that neuropsychological heterogeneity warrants more examination in ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
We have found a new stable spin state in the A-like phase of superfluid 3He confined to intrinsically anisotropic aerogel. The state can be formed by radiofrequency excitation applied while cooling through the superfluid transition temperature and its NMR properties are different from the standard A-like phase obtained in the limit of very small excitation. It is possible that this new state is formed by textural domain walls pinned by aerogel.   相似文献   
3.
(1) Objective: Considering that current knowledge of mechanisms involved in the molecular pathogenesis of Social Anxiety Disorder (SAD) is limited, we conducted a systematic review to evaluate cumulative data obtained by Proton Magnetic Resonance Spectroscopic (1H MRS) studies. (2) Methods: A computer-based literature search of Medline, EMBASE, PsycInfo, and ProQuest was performed. Only cross-sectional studies using 1H MRS techniques in participants with SAD and healthy controls (HCs) were selected. (3) Results: The search generated eight studies. The results indicated regional abnormalities in the ‘fear neurocircuitry’ in patients with SAD. The implicated regions included the anterior cingulate cortex (ACC), dorsomedial prefrontal cortex (dmPFC), dorsolateral prefrontal cortex (dlPFC), insula, occipital cortex (OC), as well as the subcortical regions, including the thalamus, caudate, and the putamen. (4) Conclusions: The evidence derived from eight studies suggests that possible pathophysiological mechanisms of SAD include impairments in the integrity and function of neurons and glial cells, including disturbances in energy metabolism, maintenance of phospholipid membranes, dysregulations of second messenger systems, and excitatory/inhibitory neurocircuitry. Conducting more cross-sectional studies with larger sample sizes is warranted given the limited evidence in this area of research.  相似文献   
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5.
There is growing evidence that social media addiction is an evolving problem, particularly among adolescents. However, the absence of an instrument measuring social media addiction hinders further development of the research field. The present study, therefore, aimed to test the reliability and validity of a short and easy to administer Social Media Disorder (SMD) Scale that contains a clear diagnostic cut-off point to distinguish between disordered (i.e. addicted) and high-engaging non-disordered social media users.Three online surveys were conducted among a total of 2198 Dutch adolescents aged 10 to 17. The 9-item scale showed solid structural validity, appropriate internal consistency, good convergent and criterion validity, sufficient test-retest reliability, and satisfactory sensitivity and specificity. In sum, this study generated evidence that the short 9-item scale is a psychometrically sound and valid instruments to measure SMD.  相似文献   
6.
The introduction of Computerized Numeric Control (CNC) technology in manufacturing industries revolutionized the production process a few decades back. There are some health and safety problems associated with these machine operations, however. The main objectives of the present work is to study the health and safety issues associated with the CNC machines with respect to control and display, specifically to determine the frequency, intensity of discomfort, and its interference in operating different CNC machines as reported by the workers operating them. The postural discomfort associated with CNC machines was studied, and the frequency, intensity of discomfort, and interference of the level of discomfort with the participants' ability to work were recorded and analyzed. The study revealed that 20.5% of the operators reported discomfort 1 or 2 times, 25.4% experienced discomfort 3 to 4 times in a week, 37.7% had discomfort daily, and 16.4% reported discomfort several times a day. Discomfort was reported in all the body parts involved (lower back, neck, upper back, shoulder, and leg), but the highest discomfort scores were associated with the shoulder and arm region. Workers reporting discomfort several times a day also reported high mean discomfort scores. The study established that the frequency and intensity of the discomfort in all body parts is related to the position of the control panel and display. © 2012 Wiley Periodicals, Inc.  相似文献   
7.
Within Australian cities, social and economic inequalities manifest themselves spatially. Perceived neighbourhood disorder and neighbourhood reputation are relevant to considering the ways in which social and economic inequalities translate into place-based inequalities. This article explores the ways in which residents of two socio-economically contrasting urban areas describe and explain neighbourhood disorder and neighbourhood reputation. It draws upon qualitative data from 40 in-depth interviews, in addition to quantitative data from a postal survey. The qualitative findings highlighted how issues of neighbourhood disorder and reputation were intertwined. In both areas, participants sought to portray themselves and their neighbourhoods in positive ways, by attributing responsibility for neighbourhood disorder to people who were unlike themselves, and by highlighting places that were perceived to have worse reputations and higher levels of disorder. The findings are considered in light of Bourdieu's theory of capitals. This article indicates that both neighbourhood disorder and reputation are pathways through which social, economic and health inequities are maintained in urban areas.  相似文献   
8.
Although several measures of obsessive-compulsive (OC) symptoms exist, most are limited in that they are not consistent with the most recent empirical findings on the nature and dimensional structure of obsessions and compulsions. In the present research, the authors developed and evaluated a measure called the Dimensional Obsessive-Compulsive Scale (DOCS) to address limitations of existing OC symptom measures. The DOCS is a 20-item measure that assesses the four dimensions of OC symptoms most reliably replicated in previous structural research. Factorial validity of the DOCS was supported by exploratory and confirmatory factor analyses of 3 samples, including individuals with OC disorder, those with other anxiety disorders, and nonclinical individuals. Scores on the DOCS displayed good performance on indices of reliability and validity, as well as sensitivity to treatment and diagnostic sensitivity, and hold promise as a measure of OC symptoms in clinical and research settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Internet addiction is “an individual’s inability to control their Internet use, which in turn leads to feelings of distress and functional impairment of daily activities” [Shapira, N., Lessig, M., Goldsmith, T., Szabo, S., Lazoritz, M., Gold, M. et al. (2003). Problematic Internet use: Proposed classification and diagnostic criteria. Depression and Anxiety, 17(4), 207–216]. Previous research in this field has offered inconclusive data on whether Internet addiction can be classified as a disorder. This study provides an in-depth and comprehensive analysis of internet addiction through a meta-synthesis of qualitative studies on excessive Internet use published during the period of 1996–2006. Several constructs pertaining to the domain of Internet addiction have been identified and a theoretical model of Internet addiction has been proposed.  相似文献   
10.
The anisotropic effect of a hcp 4He solid matrix on cesium atoms has been proposed as a tool to reveal the parity violating anapole moment of its nucleus. It should also result in splitting the D2 optical excitation line in a way depending on the light polarization. An experimental investigation has been set up using oriented hcp helium crystals in which cesium metal grains are embedded. Atoms are created by laser sputtering from this grains. Optical absorption spectra of the D2 line have been recorded in the temperature range of 1.0 to 1.4 K at liquid/solid coexistence pressure by monitoring the fluorescence on the D2 line at 950 nm. No significant effect of the light polarization has been found, suggesting a statistically isotropic disordered solid environment for the cesium atoms.   相似文献   
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