Three generalizability studies of the components of perceived coach support

addresses: Sport and Health Sciences, University of Exeter, Exeter, U.K.types: Journal Article© 2012 Human Kinetics, IncCoaches are important providers of social support, but what influences us to perceive our coaches as supportive or unsupportive? We investigated the extent to which perceptions of coach support reflect characteristics of athletes and coaches, as well as relational components. In three studies, athletes judged the actual or hypothetical supportiveness of various coaches. The methods of generalizability theory permitted us to conclude that perceptions of coach support primarily reflected relational components, with characteristics both of athletes and coaches also independently playing (lesser) roles. These findings suggest that athletes may systematically disagree on the supportiveness of their coaches

Collective Antenna Effects in the Terahertz and Infrared Response of Highly Aligned Carbon Nanotube Arrays

We study macroscopically-aligned single-wall carbon nanotube arrays with uniform lengths via polarization-dependent terahertz and infrared transmission spectroscopy. Polarization anisotropy is extreme at frequencies less than $\sim$3 THz with no sign of attenuation when the polarization is perpendicular to the alignment direction. The attenuation for both parallel and perpendicular polarizations increases with increasing frequency, exhibiting a pronounced and broad peak around 10 THz in the parallel case. We model the electromagnetic response of the sample by taking into account both radiative scattering and absorption losses. We show that our sample acts as an effective antenna due to the high degree of alignment, exhibiting much larger radiative scattering than absorption in the mid/far-infrared range. Our calculated attenuation spectrum clearly shows a non-Drude peak at $\sim$10 THz in agreement with the experiment.Comment: 5 pages, 5 figure

Ambient temperature versus ambient acceleration in the circular motion Unruh effect

It is well known that the experience of a linearly accelerated observer with acceleration a, interacting with a massless scalar field in its vacuum state in 3+1 Minkowski spacetime, is identical to that of a static observer interacting with a massless scalar field in a thermal state of temperature a/2π in 3+1 Minkowski spacetime. We study the robustness of this duality by comparing an observer undergoing circular motion in a thermal bath with an observer that undergoes circular motion around a linearly accelerated trajectory. We find that in most regimes, observers in these two cases experience the field in different ways, and are generally able to tell the difference between the two cases by measuring observables localized along their trajectories

Projected sea level rise and changes in extreme storm surge and wave events during the 21st century in the region of Singapore

Singapore is an island state with considerable population, industries, commerce and transport located in coastal areas at elevations less than 2 m making it vulnerable to sea-level rise. Mitigation against future inundation events requires a quantitative assessment of risk. To address this need, regional projections of changes in (i) long-term mean sea level and (ii) the frequency of extreme storm surge and wave events have been combined to explore potential changes to coastal flood risk over the 21st century. Local changes in time mean sea level were evaluated using the process-based climate model data and methods presented in the IPCC AR5. Regional surge and wave solutions extending from 1980 to 2100 were generated using ~ 12 km resolution surge (Nucleus for European Modelling of the Ocean – NEMO) and wave (WaveWatchIII) models. Ocean simulations were forced by output from a selection of four downscaled (~ 12 km resolution) atmospheric models, forced at the lateral boundaries by global climate model simulations generated for the IPCC AR5. Long-term trends in skew surge and significant wave height were then assessed using a generalised extreme value model, fit to the largest modelled events each year. An additional atmospheric solution downscaled from the ERA-Interim global reanalysis was used to force historical ocean model simulations extending from 1980–2010, enabling a quantitative assessment of model skill. Simulated historical sea surface height and significant wave height time series were compared to tide gauge data and satellite altimetry data respectively. Central estimates of the long-term mean sea level rise at Singapore by 2100 were projected to be 0.52 m (0.74 m) under the RCP 4.5 (8.5) scenarios respectively. Trends in surge and significant wave height 2 year return levels were found to be statistically insignificant and/or physically very small under the more severe RCP8.5 scenario. We conclude that changes to long-term mean sea level constitute the dominant signal of change to the projected inundation risk for Singapore during the 21st century. We note that the largest recorded surge residual in the Singapore Strait of ~ 84 cm lies between the central and upper estimates of sea level rise by 2100, highlighting the vulnerability of the region

Gene Expression Changes in the Prefrontal Cortex, Anterior Cingulate Cortex and Nucleus Accumbens of Mood Disorders Subjects That Committed Suicide

Suicidal behaviors are frequent in mood disorders patients but only a subset of them ever complete suicide. Understanding predisposing factors for suicidal behaviors in high risk populations is of major importance for the prevention and treatment of suicidal behaviors. The objective of this project was to investigate gene expression changes associated with suicide in brains of mood disorder patients by microarrays (Affymetrix HG-U133 Plus2.0) in the dorsolateral prefrontal cortex (DLPFC: 6 Non-suicides, 15 suicides), the anterior cingulate cortex (ACC: 6NS, 9S) and the nucleus accumbens (NAcc: 8NS, 13S). ANCOVA was used to control for age, gender, pH and RNA degradation, with P≤0.01 and fold change±1.25 as criteria for significance. Pathway analysis revealed serotonergic signaling alterations in the DLPFC and glucocorticoid signaling alterations in the ACC and NAcc. The gene with the lowest p-value in the DLPFC was the 5-HT2A gene, previously associated both with suicide and mood disorders. In the ACC 6 metallothionein genes were down-regulated in suicide (MT1E, MT1F, MT1G, MT1H, MT1X, MT2A) and three were down-regulated in the NAcc (MT1F, MT1G, MT1H). Differential expression of selected genes was confirmed by qPCR, we confirmed the 5-HT2A alterations and the global down-regulation of members of the metallothionein subfamilies MT 1 and 2 in suicide completers. MTs 1 and 2 are neuro-protective following stress and glucocorticoid stimulations, suggesting that in suicide victims neuroprotective response to stress and cortisol may be diminished. Our results thus suggest that suicide-specific expression changes in mood disorders involve both glucocorticoids regulated metallothioneins and serotonergic signaling in different regions of the brain

Reduction in Phencyclidine Induced Sensorimotor Gating Deficits in the Rat Following Increased System Xc − Activity in the Medial Prefrontal Cortex

Rationale: Aspects of schizophrenia, including deficits in sensorimotor gating, have been linked to glutamate dysfunction and/or oxidative stress in the prefrontal cortex. System xc −, a cystine–glutamate antiporter, is a poorly understood mechanism that contributes to both cellular antioxidant capacity and glutamate homeostasis. Objectives: Our goal was to determine whether increased system xc − activity within the prefrontal cortex would normalize a rodent measure of sensorimotor gating. Methods: In situ hybridization was used to map messenger RNA (mRNA) expression of xCT, the active subunit of system xc −, in the prefrontal cortex. Prepulse inhibition was used to measure sensorimotor gating; deficits in prepulse inhibition were produced using phencyclidine (0.3–3 mg/kg, sc). N-Acetylcysteine (10–100 μM) and the system xc − inhibitor (S)-4-carboxyphenylglycine (CPG, 0.5 μM) were used to increase and decrease system xc − activity, respectively. The uptake of 14C-cystine into tissue punches obtained from the prefrontal cortex was used to assay system xc − activity. Results: The expression of xCT mRNA in the prefrontal cortex was most prominent in a lateral band spanning primarily the prelimbic cortex. Although phencyclidine did not alter the uptake of 14C-cystine in prefrontal cortical tissue punches, intraprefrontal cortical infusion of N-acetylcysteine (10–100 μM) significantly reduced phencyclidine- (1.5 mg/kg, sc) induced deficits in prepulse inhibition. N-Acetylcysteine was without effect when coinfused with CPG (0.5 μM), indicating an involvement of system xc −. Conclusions: These results indicate that phencyclidine disrupts sensorimotor gating through system xc − independent mechanisms, but that increasing cystine–glutamate exchange in the prefrontal cortex is sufficient to reduce behavioral deficits produced by phencyclidine

Social Isolation-Induced Aggression Potentiates Anxiety and Depressive-Like Behavior in Male Mice Subjected to Unpredictable Chronic Mild Stress

Accumulating epidemiological evidence shows that life event stressors are major vulnerability factors for psychiatric diseases such as major depression. It is also well known that social isolation in male mice results in aggressive behavior. However, it is not known how social isolation-induced aggression affects anxiety and depressive-like behavior in isolated male mice subjected to unpredictable chronic mild stress (CMS), an animal model of depression.C57/B6 male mice were divided into 3 groups; non-stressed controls, in Group I; isolated mice subjected to the CMS protocol in Group II and aggression by physical contact in socially isolated mice subjected to the CMS protocol in Group III. In the sucrose intake test, ingestion of a 1% sucrose solution by mice in Groups II and III was significantly lower than in Group I. Furthermore, intake of this solution in Group III mice was significantly lower than in Group II mice. In the open field test, mice in Group III, showed reduced locomotor activity and reduced entry and retention time in the central zone, compared to Groups I and II mice. Moreover, the distances moved in 1 hour by Group III mice did not differ between night and morning. In the light/black box test, Groups II and III animals spent significantly less time in the light box compared to Group I animals. In the tail suspension test (TST) and forced swimming test (FST), the immobility times of Group II and Group III mice were significantly longer than in Group I mice. In addition, immobility times in the FST were significantly longer in Group III than in Group II mice.These findings show that social isolation-induced aggression could potentiate anxiety and depressive-like behaviors in isolated male mice subjected to CMS

CSF biochemical correlates of mixed affective states

To evaluate the question of whether “mixed” bipolar disorder is a distinct entity, we compared selected cerebrospinal fluid (CSF) biochemical parameters from patients with bipolar disorder, mixed, to those with mania and major depression. Fourteen patients in each category (DSM-III) were studied with regard to CSF HVA, 5HIAA, sodium, potassium, calcium, and magnesium levels under carefully controlled conditions. CSF HVA, 5HIAA, and sodium were found to be significantly higher in manics than in major depressives. Discriminant analysis of the biochemical variables of the mixed affective group identified two biochemically distinct and clinically different subgroups of seven patients each, one resembling the manic group and the other the major depressive group. These findings suggest that mixed affective states do not exist as a separate entity, but are compsed of two subgroups obtained from the manic and major depressive categories.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66203/1/j.1600-0447.1988.tb06339.x.pd

Identification of 14-3-3γ as a Mieap-interacting protein and its role in mitochondrial quality control

Mieap, a p53-inducible protein, controls mitochondrial integrity by inducing the accumulation of lysosomal proteins within mitochondria. This phenomenon is designated MALM, for Mieap-induced accumulation of lysosome-like organelles within mitochondria. To identify this novel Mieap-interacting protein(s), we performed a two-dimensional image-converted analysis of liquid chromatography and mass spectrometry (2DICAL) on the proteins immunoprecipitated by an anti-Mieap antibody. We indentified 14-3-3γ as one of the proteins that was included in the Mieap-binding protein complex when MALM was induced. The interaction between Mieap and 14-3-3γ was confirmed on the exogenous and endogenous proteins. Interestingly, 14-3-3γ was localized within mitochondria when MALM occurred. A 14-3-3γ deficiency did not affect the accumulation of Mieap and lysosomal proteins within mitochondria, but dramatically inhibited the elimination of oxidized mitochondrial proteins. These results suggest that 14-3-3γ plays a critical role in eliminating oxidized mitochondrial proteins during the MALM process by interacting with Mieap within mitochondria

Pramipexole effects on startle gating in rats and normal men

Dopamine D3 receptors regulate sensorimotor gating in rats, as evidenced by changes in prepulse inhibition (PPI) of startle after acute administration of D3 agonists and antagonists. In this study, we tested the effects of the D3-preferential agonist, pramipexole, on PPI in normal men and Sprague–Dawley rats. Acoustic startle and PPI were tested in clinically normal men, comparing the effects of placebo vs. 0.125 mg (n = 20) or placebo vs. 0.1875 mg (n = 20) pramipexole, in double blind, crossover designs. These measures were also tested in male Sprague–Dawley rats using a parallel design [vehicle vs. 0.1 mg/kg (n = 8), vehicle vs. 0.3 mg/kg (n = 8) or vehicle vs. 1.0 mg/kg pramipexole (n = 8)]. Autonomic and subjective measures of pramipexole effects and several personality instruments were also measured in humans. Pramipexole increased drowsiness and significantly increased PPI at 120-ms intervals in humans; the latter effect was not moderated by baseline PPI or personality scale scores. In rats, pramipexole causes a dose-dependent reduction in long-interval (120 ms) PPI, while low doses actually increased short-interval (10–20 ms) PPI. Effects of pramipexole on PPI in rats were independent of baseline PPI and changes in startle magnitude. The preferential D3 agonist pramipexole modifies PPI in humans and rats. Unlike indirect DA agonists and mixed D2/D3 agonists, pramipexole increases long-interval PPI in humans, in a manner that is independent of baseline PPI and personality measures. These findings are consistent with preclinical evidence for differences in the D2- and D3-mediated regulation of sensorimotor gating