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Iraq and Afghanistan Veterans with posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI) history have high rates of performance validity test (PVT) failure. The study aimed to determine whether those with scores in the invalid versus valid range on PVTs show similar benefit from psychotherapy and if psychotherapy improves PVT performance.
Veterans (N = 100) with PTSD, mild-to-moderate TBI history, and cognitive complaints underwent neuropsychological testing at baseline, post-treatment, and 3-month post-treatment. Veterans were randomly assigned to cognitive processing therapy (CPT) or a novel hybrid intervention integrating CPT with TBI psychoeducation and cognitive rehabilitation strategies from Cognitive Symptom Management and Rehabilitation Therapy (CogSMART). Performance below standard cutoffs on any PVT trial across three different PVT measures was considered invalid (PVT-Fail), whereas performance above cutoffs on all measures was considered valid (PVT-Pass).
Although both PVT groups exhibited clinically significant improvement in PTSD symptoms, the PVT-Pass group demonstrated greater symptom reduction than the PVT-Fail group. Measures of post-concussive and depressive symptoms improved to a similar degree across groups. Treatment condition did not moderate these results. Rate of valid test performance increased from baseline to follow-up across conditions, with a stronger effect in the SMART-CPT compared to CPT condition.
Both PVT groups experienced improved psychological symptoms following treatment. Veterans who failed PVTs at baseline demonstrated better test engagement following treatment, resulting in higher rates of valid PVTs at follow-up. Veterans with invalid PVTs should be enrolled in trauma-focused treatment and may benefit from neuropsychological assessment after, rather than before, treatment.
Attention impairment is an under-investigated feature and diagnostic criterion of Major Depressive Disorder (MDD) that is associated with poorer outcomes. Despite increasing knowledge regarding mechanisms of attention in healthy adults, we lack a detailed characterization of attention impairments and their neural signatures in MDD.
Here, we focus on selective attention and advance a deep multi-modal characterization of these impairments in MDD, using data acquired from n = 1008 patients and n = 336 age- and sex-matched healthy controls. Selective attention impairments were operationalized and anchored in a behavioral performance measure, assessed within a battery of cognitive tests. We sought to establish the accompanying neural signature using independent measures of functional magnetic resonance imaging (15% of the sample) and electroencephalographic recordings of oscillatory neural activity.
Greater impairment on the behavioral measure of selective attention was associated with intrinsic hypo-connectivity of the fronto-parietal attention network. Not only was this relationship specific to the fronto-parietal network unlike other large-scale networks; this hypo-connectivity was also specific to selective attention performance unlike other measures of cognition. Selective attention impairment was also associated with lower posterior alpha (8–13 Hz) power at rest and was related to more severe negative bias (frequent misidentifications of neutral faces as sad and lingering attention on sad faces), relevant to clinical features of negative attributions and brooding. Selective attention impairments were independent of overall depression severity and of worrying or sleep problems.
These results provide a foundation for the clinical translational development of objective markers and targeted therapeutics for attention impairment in MDD.
The intensities of x-rays scattered by amorphous Fe80P13C7 and Fe40Ni40P14B6 samples have been measured as a function of photon energies E at fixed scattering angles 2θi using a Li-drifted Si detector and polychromatic x-rays generated by a 50KV full-wave rectified generator. The coherently scattered intensity per atom was calculated for free-standing samples as well as samples contained in a Be or pyrolytic graphite cell, after the evaluation of the energy dependence of the primary beam spectrum by an iterative process. The interference functions were then calculated from the data obtained in transmission and reflection, and compared with those measured with the conventional variable 2θ technique. Good agreement between energy-dispersive diffraction (also called variable wavelength technique) and variable 2θ diffraction was observed in all cases.
Environmental factors such as sunshine hours, temperature and UV radiation (UVR) are known to influence seasonal fluctuations in vitamin D concentrations. However, currently there is poor understanding regarding the environmental factors or individual characteristics that best predict neonatal 25-hydroxyvitamin D (25(OH)D) concentrations. The aims of this study were to (1) identify environmental and individual determinants of 25(OH)D concentrations in newborns and (2) investigate whether environmental factors and individual characteristics could be used as proxy measures for neonatal 25(OH)D concentrations. 25-Hydroxyvitamin D3 (25(OH)D3) was measured from neonatal dried blood spots (DBS) of 1182 individuals born between 1993 and 2002. Monthly aggregated data on daily number of sunshine hours, temperature and UVR, available from 1993, were retrieved from the Danish Meteorological Institute. The individual predictors were obtained from the Danish National Birth register, and Statistics Denmark. The optimal model to predict 25(OH)D3 concentrations from neonatal DBS was the one including the following variables: UVR, temperature, maternal education, maternal smoking during pregnancy, gestational age at birth and parity. This model explained 30 % of the variation of 25(OH)D3 in the neonatal DBS. Ambient UVR in the month before the birth month was the best single-item predictor of neonatal 25(OH)D3, accounting for 24 % of its variance. Although this prediction model cannot substitute for actual blood measurements, it might prove useful in cohort studies ranking individuals in groups according to 25(OH)D3 status.
Studies have suggested that vitamin D status at birth may be associated with a range of neonatal outcomes. The aim of this study was to assess the association between neonatal 25-hydroxyvitamin D3 (25(OH)D3) concentration and gestational age, birth weight, Ponderal Index and size for gestational age. Neonatal capillary blood stored as dried blood spots was used to assess 25(OH)D3 concentrations among 2686 subjects selected from a random population sub-sample of individuals, born in Denmark from 1 May 1981 to 31 December 2002. There was an inverse association between 25(OH)D3 concentration and gestational age at birth of −0·006 (95 % CI −0·009, −0·003, P<0·001) weeks of gestation per 1 nmol/l increase in 25(OH)D3 concentration. An inverted U-shaped association between 25(OH)D3 and birth weight and Ponderal Index (P=0·04) was found, but no association with size for gestational age was shown. This study suggests that neonatal 25(OH)D3 concentration is associated with anthropometric measures at birth known to be correlated with many subsequent health outcomes such as obesity and type 2 diabetes.
The abundances of Ni, Fe, Cr, Mn, P, Cu, K, Na, Ga, Ge, Se, Zn, S, Br, and C were measured in interplanetary dust particles (IDPs) collected from the Earth's stratosphere. All elements with nebular condensation temperatures lower than Mn, except S, were enriched relative to the most volatile-rich type of meteorite while the refractory elements Cr and Ni were present at chondritic abundances. This element abundance pattern is consistent with nebular condensation, suggesting the IDPs condensed at either a different location or time in the evolving solar nebula than do the meteorites. The enrichments of the major elements C, Na, P, and K exclude the possibility that the volatile enrichment in IDPs results from a minor amount of contamination.
Over 100 individual and cluster interplanetary dust particles (IDPs) have been analyzed for bulk abundances of 15 elements (C, O, Na, Mg, Al, Si, P, S, K, Ca, Ti, Cr, Mn, Fe, Ni). In general, IDPs have chondritic major element abundances, within a factor of 2 of the CI chondrites, and have carbon contents which average ~2-3 times higher than that of the most primitive, carbon-rich, carbonaceous meteorites (CI). The C-rich material is largely amorphous and is distributed throughout the particle as a matrix surrounding individual grains. The carbonaceous material has either smooth or vesicular texture; the latter texture suggests that volatiles could have been lost by particle heating which occurs during entry through the Earth's atmosphere.
All extraterrestrial particles are heated during their passage through the Earth's atmosphere. The mineral assemblages that form during entry heating can be used to constrain the maximum temperature attained which, in turn, places limits on their entry velocity Entry velocity can be used to discriminate typical cometary IDPs from asteroidal particles.
A common feature of heated IDPs is the presence of magnetite (Mt) rims on the particle surface. These rims range from thin, discontinuous Mt layers on lobes or on small constituent grains within lightly heated IDPs, to thick, continuous, polycrystalline rims that completely surround many strongly heated particles. Petrographic evidence indicates that Mt rims form directly from individual phases in IDPs via oxidation of Fe from the host phases. Our data indicate that the temperature of magnetite formation can range from a minimum of ~600°C (by decarbonation of Fe-bearing carbonates and the breakdown of phyllosilicates) to T > 850°C (decomposition of laihunite). In extreme cases, μm-sized Mt plates armor the surface of partly melted chondritic IDPs. Magnetite rims are more well-developed on hydrated IDPs than on anhydrous particles. The development of magnetite rims correlates with other independent indicators of heating including loss of volatile trace elements and sulfur depletions.
Interplanetary dust particles (IDPs), ∼ 10μm particles from comets and asteroids, have been collected by NASA from the Earth's stratosphere. We compared carbon X-ray Absorption Near-Edge Structure (XANES) and Fourier Transform Infra-Red (FTIR) spectra of anhydrous and hydrated interplanetary dust particles and found that anhydrous and hydrated IDPs have similar types and abundances of organic carbon. This is different from results on meteorites, which show that hydrated carbonaceous meteorites contain abundant organic matter, while anhydrous carbonaceous meteorites contain less carbon mostly in elemental form. But all anhydrous carbonaceous meteorites are depleted in moderately volatile and volatile elements in a pattern that suggested they experienced temperatures in excess of 1200°C, a temperature sufficient to destroy any organic matter they originally contained, while many anhydrous IDPs show no evidence of severe heating. These IDP results indicate that the bulk of the pre-biotic organic matter in extraterrestrial materials formed before aqueous processing, possibly by irradiation of C-bearing ices or by a Fisher-Tropsch type process operating in the gas phase of the nebula or in the interstellar medium.
The North Greenland Icecore Project (NorthGRIP) deep drilling site (75˚05’47’’N, 42˚19’42’’ W) is located at the north-northwest ridge of the Greenland ice sheet, 320 km from Summit. A strain net has been established around the NorthGRIP site and surveyed with global positioning system. Our results show that ice flows with a horizontal surface velocity of 1.329 ±0.015ma–1 along the ridge. Estimated principal surface strain rates at NorthGRIP are and in the directions along and transverse to the north-northwest ridge, respectively, i.e. ice is compressed along the ridge but stretched transverse to the ridge. Possible implications of the observed flow pattern for the stratigraphy are discussed. the average thickening rate in the strain-net area is found to be ∂H/∂t = 0.00 ±0.04ma– 1, in agreement with previous estimates of mass balance in high-elevation areas of Greenland.
Surface strain rates around the southeastern dome of Hans Tausen Iskappe in Peary Land, North Greenland (82.5° N, 27.5° W), are determined from global positioning system surveys of a strain net. Average longitudinal surface strain rate increases towards the dome, from (1.4 ± 0.2) × 10−4 a−1 at 5–10 ice thicknesses from the divide to (2.4 ± 1.0) × 10−4 a−1 within 1 ice thickness from the divide. Analysis of the data shows that the ice cap is presently building up within the strain net with an average rate of 〈∂H/∂t〉 = + 0.04 ± 0.02 m a−1. Assuming a uniform thickening, the shape factor of the horizontal velocity (the ratio between the vertically averaged horizontal velocity and the horizontal surface velocity) decreases towards the dome, from 0.9 at a distance of 10 ice thicknesses from the dome to 0.5 at the dome based on application of the continuity equation. Our results indicate that a region with anomalous flow is formed around the dome, supporting recent indications reported by Vaughan and others (1999). It is not possible from our data to constrain parameters of the flow law, because there is no independent estimate of the significant present thickening of the central part of the ice cap and its pattern around the dome.
To assess hospital surgical-site infection (SSI) identification and reporting following colon surgery and abdominal hysterectomy via a statewide external validation
Infection preventionists (IPs) from the California Department of Public Health (CDPH) performed on-site SSI validation for surgical procedures performed in hospitals that voluntarily participated. Validation involved chart review of SSI cases previously reported by hospitals plus review of patient records flagged for review by claims codes suggestive of SSI. We assessed the sensitivity of traditional surveillance and the added benefit of claims-based surveillance. We also evaluated the positive predictive value of claims-based surveillance (ie, workload efficiency).
Upon validation review, CDPH IPs identified 239 SSIs following colon surgery at 42 hospitals and 76 SSIs following abdominal hysterectomy at 34 hospitals. For colon surgery, traditional surveillance had a sensitivity of 50% (47% for deep incisional or organ/space [DI/OS] SSI), compared to 84% (88% for DI/OS SSI) for claims-based surveillance. For abdominal hysterectomy, traditional surveillance had a sensitivity of 68% (67% for DI/OS SSI) compared to 74% (78% for DI/OS SSI) for claims-based surveillance. Claims-based surveillance was also efficient, with 1 SSI identified for every 2 patients flagged for review who had undergone abdominal hysterectomy and for every 2.6 patients flagged for review who had undergone colon surgery. Overall, CDPH identified previously unreported SSIs in 74% of validation hospitals performing colon surgery and 35% of validation hospitals performing abdominal hysterectomy.
Claims-based surveillance is a standardized approach that hospitals can use to augment traditional surveillance methods and health departments can use for external validation.
Time series spectra of the F5IV star Procyon (α CMi) were obtained at the Kitt Peak National Observatory during a 35-night observing run in January-February 1997. The observations were obtained as part of an international collaboration to detect and study acoustic p-mode oscillations in solar-type stars. Spectra covered the wavelength range from 4000 to 5300 Å, with a resolving power of approximately 3500 (1.3 Å resolution). The sampling rate was one observation per minute, and the typical S/N ratio per pixel after averaging along columns is in excess of 1000. We obtained 12,888 spectra. A sample spectrum is shown in Figure 1
A new deep ice-core drilling site has been identified in north Greenland at 75.12° N, 42.30° W, 316 km north-northwest (NNW) of the GRIР drill site on the summit of the ice sheet. The ice thickness here is 3085 m; the surface elevation is 2919 m.The North GRIP (NGRIP) site is identified so that ice of Eemian age (115–130 ka BP,calendar years before present) is located as far above bedrock as possible and so the thickness of the Eemian layer is as great as possible. An ice-flow model, similar to the one used to date the GRIP ice core, is used to simulate the flow along the NNW-trending ice ridge. Surface and bedrock elevations, surface accumulation-rate distribution and radio-echo sounding along the ridge have been used as model input.The surface accumulation rate drops from 0.23 m fee equivalent year−1 at GRIP to 0.19 m ice equivalent year−1 50 km from GRIP. Over the following 300km the accumulation is relatively constant, before it starts decreasing again further north. Ice thicknesses up to 3250 m bring the temperature of the basal ice up to the pressure-melting point 100–250 km from GRIP. The NGRIP site islocated 316 km from GRIP in a region where the bedrock is smooth and the accumulation rate is 0.19 m ice equivalent year−1. The modeled basal ice here has always been a few degrees below the pressure-melting point. Internal radio-echo sounding horizons can be traced between the GRIP and NGRIP sites, allowing us to date the ice down to 2300 m depth (52 ka BP). An ice-flow model predicts that the Eemian-age ice will be located in the depth range 2710–2800 m, which is 285 m above the bedrock. This is 120 m further above the bedrock, and the thickness of the Eemian layer of ice is 20 m thicker, than at the GRIP ice-core site.
Endophenotypes are laboratory-based measures hypothesized to lie in the causal chain between genes and clinical disorder, and to serve as a more powerful way to identify genes associated with the disorder. One promise of endophenotypes is that they may assist in elucidating the neurobehavioral mechanisms by which an associated genetic polymorphism affects disorder risk in complex traits. We evaluated this promise by testing the extent to which variants discovered to be associated with schizophrenia through large-scale meta-analysis show associations with psychophysiological endophenotypes.
We genome-wide genotyped and imputed 4905 individuals. Of these, 1837 were whole-genome-sequenced at 11× depth. In a community-based sample, we conducted targeted tests of variants within schizophrenia-associated loci, as well as genome-wide polygenic tests of association, with 17 psychophysiological endophenotypes including acoustic startle response and affective startle modulation, antisaccade, multiple frequencies of resting electroencephalogram (EEG), electrodermal activity and P300 event-related potential.
Using single variant tests and gene-based tests we found suggestive evidence for an association between contactin 4 (CNTN4) and antisaccade and P300. We were unable to find any other variant or gene within the 108 schizophrenia loci significantly associated with any of our 17 endophenotypes. Polygenic risk scores indexing genetic vulnerability to schizophrenia were not related to any of the psychophysiological endophenotypes after correction for multiple testing.
The results indicate significant difficulty in using psychophysiological endophenotypes to characterize the genetically influenced neurobehavioral mechanisms by which risk loci identified in genome-wide association studies affect disorder risk.
We present new UV, visual and Hα photometry obtained with the WFPC2 of NGC 330, NGC 1818, NGC 2004 and NGC 2100, four young populous clusters in the MCs. We present observational evidence for a degree of convective core overshoot in excess of that currently applied in standard models.
The Commission is intended to study the origin of the solar wind, the heliosphere, i.e., the region dominated by the supersonic solar wind, and the heliospheric interface with the interstellar medium. The activities of the Commission cover both theoretical and observational aspects of these three regions.