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The DOI for the article “Can High-Intensity Exercise Be More Pleasant? Attentional Dissociation Using Music and Video,” by Leighton Jones, Costas I. Karageorghis, and Panteleimon Ekkekakis, in the Journal of Sport and Exercise Psychology 36(5), was incorrectly printed. The correct DOI for this article is http://dx.doi.org/10.1123/jsep.2013-0251 . The online version of this article has been corrected.

Concepts: Attention, The Journal, Surnames, University of Edinburgh, People from Swansea

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The chemical composition of PM2.5 and cellular effects from exposure to fine aerosol extracts were studied for samples collected in Beijing, Tianjin, Shijiazhuang, and Hengshui, China in winter 2015. Effects of priority polycyclic aromatic hydrocarbons (PAHs) and their oxygenated derivatives (OPAHs) in PM2.5 on cell cultures were a major focus of the study. Total quantified PAHs and OPAHs at Shijiazhuang and Hengshui were higher than at Beijing and Tianjin, and benz(a)anthracene, chrysene and 1,8-naphthalic anhydride were the most abundant species. Exposure to PM2.5 extracts caused a concentration-dependent decline in cell viability and a dose-dependent increase in nitric oxide production. Two cytokines, tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6), also increased when A549 test cells were exposed to PM2.5 extracts. PAHs and OPAHs in PM2.5 can potentially cause cell damage and induce cytotoxicity and pro-inflammatory responses: benzo(a)anthracene-7,12-dione was highly correlated with NO production, dibenz(a,h)anthracene and 1,4-chrysenequinone were correlated with TNF-α production, and 1-naphthaldehyde was significantly correlated with IL-6 production. The study provides a new approach for evaluating relationships between air-quality and cell toxicity with respect to specific chemicals.

Concepts: Cell biology, Cytokines, Polycyclic aromatic hydrocarbon, Nitric oxide, Tumor necrosis factor-alpha, Aromaticity, Naphthalene, Hebei

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The effects of fine particles (PM2.5) on asthma have been widely confirmed by epidemiological research studies. However, a limited number of studies have investigated the relationship between exposure to different PM2.5 components and asthma. We characterized the PM2.5 components in a suburban site of central Taiwan and conducted a time-stratified case-crossover study to elaborate the effects of daily concentration of each PM2.5 component on asthma outpatient visits. We retrieved asthma outpatient claims for individuals less than 20 years old with a residential address in the Shalu district, Taiwan, from the National Health Insurance Research Database during 2000-2010. Multiple linear regression models were used to back extrapolate the historic concentration of individual components of PM2.5 from 2000 through to 2010, including black carbon (BC) and eight ions, namely, sulfate, nitrate (NO3(-)), ammonium, chloride, potassium (K(+)), magnesium, calcium, sodium. The odds ratio (OR) with a 95% confidence interval (CI) of individual PM2.5 components on asthma was estimated by conditional logistic regression. A total of 887 asthma outpatient visits with individuals who have an average age of 7.96±3.88 years were selected. After adjusting for confounders, we found an interquartile range (IQR) increase in BC level, an IQR increase in NO3(-) level, and an IQR increase in K(+) level that were all associated with the increased risk of asthma outpatient visits from the current day (OR = 1.18, 95% CI: 1.05-1.34; OR = 1.11, 95% CI: 1.01-1.21; and OR = 1.16, 95% CI: 1.04-1.30, respectively). The effects of these components on asthma were stronger in the cold season than in the warm season. However, we did not find any lagging effects. The results suggest that exposure to NO3(-), BC, and K(+) derived from industry-related combustion or motor vehicles emission sources may increase the risk of asthma outpatient visits, particularly during the cold season.

Concepts: Regression analysis, Logistic regression, Linear regression, Epidemiology, Econometrics, Ion, Generalized linear model, Statistical inference

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Various bone abnormalities, including osteoporosis, have been associated with chronic arsenic and cadmium exposure in experimental animal models, but information regarding the bone pathology of wild population of small mammals breeding in contaminated environment is limited. This present study was conducted to comparatively assess the prevalence and pattern of skeletal abnormalities in free ranging snowshoe hares inhabiting an area heavily contaminated by arsenic and other trace metals, near the vicinity of the abandoned Giant mine, and in a reference location approximately 20km from the city of Yellowknife, Northwest Territories, Canada. The femur and vertebrae of snowshoe hares from the mine area and reference location were subjected to bone densitometry examination and biomechanical testing using dual energy X-ray absorptiometry (DXA) and 3-point bending test. t-test results indicated that femoral densitometry parameters such as bone mineral density (BMD) (p=0.5), bone mineral content (BMC) (p=0.675), bone area (BA) (p=0.978) and tissue area (TA) (p=0.549) were not significantly different between locations. All densitometry parameters of the vertebrae (BMD, BA and TA) differed between locations (p<0.05), except for BMC (p=0.951) which showed no significant difference between the two locations. Vertebrae from the mine area also showed relatively lower BA and TA compared to the reference location. A constellation of skeletal abnormalities were also observed along the axial and appendicular bones respectively. Specifically, growth defects, osteoporosis, cortical fractures, sclerosis, and cyst like changes were commonly observed in the femurs and vertebrae of hares from both locations. With respect to biomechanical properties, only bone stiffness and peak load tended to be relatively reduced in specimens from the mine area, whereas work to failure was notably increased in specimens from the reference site compared to those from the mine area. Taken together, the results of this preliminary study suggest that chronic concomitant exposure to arsenic and cadmium may be involved in the etiology of various bone abnormalities, including osteoporosis in wild population of snowshoe hares from the Yellowknife area. The result presented in this study represent the first evaluation of osteological effects in free-ranging furbearers (snowshoe hares) diagnosed with arsenicosis, and concomitantly exposed to environmental levels of cadmium.

Concepts: Osteoporosis, Bone, Dual energy X-ray absorptiometry, Osteopenia, Hare, Leporidae, Snowshoe Hare, Yellowknife

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Despite advancements in alternative transport networks, road transport remains the dominant mode in many modern and developing countries. The ground-borne motions produced by the passage of a heavy vehicle over a geometric obstacle (e.g. speed hump, train tracks) pose a fundamental problem in transport annoyance in urban areas. In order to predict the ground vibrations generated by the passage of a heavy vehicle over a geometric obstacle, a two-step numerical model is developed. The first step involves simulating the dynamic loads generated by the heavy vehicle using a multibody approach, which includes the tyre-obstacle-ground interaction. The second step involves the simulation of the ground wave propagation using a three dimensional finite element model. The simulation is able to be decoupled due to the large difference in stiffness between the vehicle’s tyres and the road. First, the two-step model is validated using an experimental case study available in the literature. A sensitivity analysis is then presented, examining the influence of various factors on the generated ground vibrations. Factors investigated include obstacle shape, obstacle dimensions, vehicle speed, and tyre stiffness. The developed model can be used as a tool in the early planning stages to predict the ground vibrations generated by the passage of a heavy vehicle over an obstacle in urban areas.

Concepts: Mathematics, Dimension, Transport, Computer simulation, Walking, Road transport, Automobile, Internal combustion engine

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A single low-dose ketamine infusion exhibited a rapid antidepressant effect within 1h. Despite its short biological half-life (approximately 3h), the antidepressant effect of ketamine has been demonstrated to persist for several days. However, changes in brain function responsible for the persistent antidepressant effect of a single low-dose ketamine infusion remain unclear METHODS: Twenty-four patients with treatment-resistant depression (TRD) were randomized into three groups according to the treatment received: 0.5mg/kg ketamine, 0.2mg/kg ketamine, and normal saline infusion. Standardized uptake values (SUVs) of glucose metabolism measured through (18)F-FDG positron-emission-tomography before infusion and 1day after a 40-min ketamine or normal saline infusion were used for subsequent whole-brain voxel-wise analysis and were correlated with depressive symptoms, as defined using the Hamilton Depression Rating Scale-17 (HDRS-17) score RESULTS: The voxel-wise analysis revealed that patients with TRD receiving the 0.5mg/kg ketamine infusion had significantly higher SUVs (corrected for family-wise errors, P = 0.014) in the supplementary motor area (SMA) and dorsal anterior cingulate cortex (dACC) than did those receiving the 0.2mg/kg ketamine infusion. The increase in the SUV in the dACC was negatively correlated with depressive symptoms at 1day after ketamine infusion DISCUSSION: The persistent antidepressant effect of a 0.5mg/kg ketamine infusion may be mediated by increased activation in the SMA and dACC. The higher increase in dACC activation was related to the reduction in depressive symptoms after ketamine infusion. A 0.5mg/kg ketamine infusion facilitated the glutamatergic neurotransmission in the SMA and dACC, which may be responsible for the persistent antidepressant effect of ketamine much beyond its half-life.

Concepts: Neuroanatomy, Cerebral cortex, Cerebrum, Major depressive disorder, Brodmann area 24, Anterior cingulate cortex, Cingulate cortex, Ketamine

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Borderline personality disorder (BPD) has a pervasive pattern of instability in interpersonal relationships, self-image, and emotions. BPD may be linked to an abnormal brain anatomy, but little is known about possible impairments of the white matter microstructure in BPD or their relationship with impulsivity or risky behaviors. The aims of the present study were to explore the relationship between BPD and diffusion tensor imaging (DTI) parameters and psychological tests.

Concepts: Psychology, Personality psychology, Interpersonal relationship, Abnormal psychology, Borderline personality disorder, Personality disorder, Antisocial personality disorder, Histrionic personality disorder

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The DSM-5 mixed features specifier for mood disorders encourages renewed interest in mixed states and led us to pool research findings regarding prevalence of mixed features in episodes of major depressive (MDD) and bipolar disorders (BD).

Concepts: Schizophrenia, Bipolar disorder, Major depressive disorder, Mood disorder, Dysthymia, Mania, Creativity, Mood

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The majority of internationally adopted children, before adoption, might have experienced malnutrition, exposure to infectious diseases, environmental deprivation and neglect; they could also develop medical problems such as vitamin D deficiency. Scantly data are available about vitamin D status in internationally adopted children and, to our knowledge, no report exists on Italian adoptees.

Concepts: Vitamin D, Infectious disease, Family law, Adoption, Philosophy of science, Knowledge, Adoptees, Plato

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We explored the correlation between the TGFBR2 gene that is mediated by NF-kb signaling pathways and the pathogenesis of Kawasaki disease in children.

Concepts: Gene, Gene expression, Transcription