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Predicting suicides after outpatient mental health visits in the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS).
The 2013 US Veterans Administration/Department of Defense Clinical Practice Guidelines (VA/DoD CPG) require comprehensive suicide risk assessments for VA/DoD patients with mental disorders but provide minimal guidance on how to carry out these assessments. Given that clinician-based assessments are not known to be strong predictors of suicide, we investigated whether a precision medicine model using administrative data after outpatient mental health specialty visits could be developed to predict suicides among outpatients. We focused on male nondeployed Regular US Army soldiers because they account for the vast majority of such suicides. Four machine learning classifiers (naive Bayes, random forests, support vector regression and elastic net penalized regression) were explored. Of the Army suicides in 2004-2009, 41.5% occurred among 12.0% of soldiers seen as outpatient by mental health specialists, with risk especially high within 26 weeks of visits. An elastic net classifier with 10-14 predictors optimized sensitivity (45.6% of suicide deaths occurring after the 15% of visits with highest predicted risk). Good model stability was found for a model using 2004-2007 data to predict 2008-2009 suicides, although stability decreased in a model using 2008-2009 data to predict 2010-2012 suicides. The 5% of visits with highest risk included only 0.1% of soldiers (1047.1 suicides/100â000 person-years in the 5 weeks after the visit). This is a high enough concentration of risk to have implications for targeting preventive interventions. An even better model might be developed in the future by including the enriched information on clinician-evaluated suicide risk mandated by the VA/DoD CPG to be recorded
Hepatitis C virus infection in Brazilian long-distance truck drivers
Hepatitis C virus (HCV) infection is a global public health problem. Long-distance truck drivers live apart from their family for long periods of time, a lifestyle that favors at-risk behaviors such as unprotected sex with multiple partners and illicit drug use. As data concerning HCV infection in this population are still rare, this paper aims to investigate the prevalence, genotypes/subtypes, and the factors associated with HCV infection in long-distance truck drivers in Brazil. A cross-sectional survey was carried out with 641 Brazilian long-truck drivers who were recruited at a major truck stop located at kilometer 1,296 of the BR-153 highway, which is considered to be one of the longest roads in Brazil. All individuals were interviewed, and their serum samples were tested for the presence of antibodies to HCV (anti-HCV) by ELISA and immunoblot. Anti-HCV positive samples were tested for HCV RNA by PCR amplification of the 5' NC and NS5B regions and were genotyped using the LiPA assay and nucleotide sequencing, respectively. Factors associated with HCV infection were identified with logistic regression. The prevalence of HCV infection was 1.4% (95% CI: 0.7-2.8). History of blood transfusion, sharing of personal hygiene tools, illicit drug use and HBV status were factors independently associated with HCV infection in the study population. HCV RNA was detected in 8/9 anti-HCV positive samples, in which genotypes 1 (n = 3), 2 (n = 2), and 3 (n = 3) were determined by LiPA. Using phylogenetic tree analysis of the NS5B region, subtypes 1a (n = 1), 1b (n = 2), 2b (n = 2) and 3a (n = 3) were identified. These data show that the prevalence of HCV infection among Brazilian truck drivers was similar to that observed for the general population. History of blood transfusion, sharing of personal hygiene tools, illicit drug use and HBV status were predictors of HCV infection. The HCV genotypes/subtypes identified in the study population are consistent with those circulating in Brazil
Pressure effects on the structural and superconducting transitions in LaâCoâSnââ
La3Co4Sn13 is a superconducting material with transition temperature at Tc = 2.70 K, which
presents a superlattice structural transition at T
â â 150 K, a common feature for this class of
compounds. However, for this material, it is not clear that at T
â
the lattice distortions arise from
a charge density wave (CDW) or from a distinct microscopic origin. Interestingly, it has been
suggested in isostructural non-magnetic intermetallic compounds that T
â
can be suppressed to zero
temperature, by combining chemical and external pressure, and a quantum critical point is argued
to be observed near these critical doping/pressure. Our study shows that application of pressure
on single-crystalline La3Co4Sn13 enhances Tc and decreases T
â
. We observe thermal hysteresis
loops for cooling/heating cycles around T
â
for P & 0.6 GPa, in electrical resistivity measurements,
which are not seen in x-ray diffraction data. The hysteresis in electrical measurements may be due
to the pinning of the CDW phase to impurities/defects, while the superlattice structural transition
maintains its ambient pressure second-order transition nature under pressure. From our experiments
we estimate that T
â
vanishes at around 5.5 GPa, though no quantum critical behavior is observed
up to 2.53 GPa
Geogenetic patterns in mouse lemurs (genus Microcebus) reveal the ghosts of Madagascar's forests past.
Phylogeographic analysis can be described as the study of the geological and climatological processes that have produced contemporary geographic distributions of populations and species. Here, we attempt to understand how the dynamic process of landscape change on Madagascar has shaped the distribution of a targeted clade of mouse lemurs (genus Microcebus) and, conversely, how phylogenetic and population genetic patterns in these small primates can reciprocally advance our understanding of Madagascar's prehuman environment. The degree to which human activity has impacted the natural plant communities of Madagascar is of critical and enduring interest. Today, the eastern rainforests are separated from the dry deciduous forests of the west by a large expanse of presumed anthropogenic grassland savanna, dominated by the Family Poaceae, that blankets most of the Central Highlands. Although there is firm consensus that anthropogenic activities have transformed the original vegetation through agricultural and pastoral practices, the degree to which closed-canopy forest extended from the east to the west remains debated. Phylogenetic and population genetic patterns in a five-species clade of mouse lemurs suggest that longitudinal dispersal across the island was readily achieved throughout the Pleistocene, apparently ending at âŒ55 ka. By examining patterns of both inter- and intraspecific genetic diversity in mouse lemur species found in the eastern, western, and Central Highland zones, we conclude that the natural environment of the Central Highlands would have been mosaic, consisting of a matrix of wooded savanna that formed a transitional zone between the extremes of humid eastern and dry western forest types
Wind-pattern circulation as a palaeogeographic indicator: case study of the 1.5-1.6 Ga Mangabeira Formation, SĂŁo Francisco Craton, Northeast Brazil
The preserved deposits of dune-scale aeolian bedforms provide valuable palaeoenvironmental indicators of atmospheric circulation patterns and the latitudinal position and distribution of land masses. However, no attempts to use palaeowind directions and palaeogeographic reconstructions of ancient land mass distribution have been published to model Precambrian atmospheric circulation. The Mangabeira Formation is a large Mesoproterozoic aeolian erg succession (1.6 to 1.5 Ga) composed of two aeolian units that accumulated in the São Francisco Craton, Brazil. The Lower Unit records multiple drying-upward depositional cycles, each of which represents an episode of erg expansion and contraction driven by climate changes. The Upper Unit is composed dominantly of stacked aeolian dune strata that lack intervening interdune deposits and which record extreme aridity. Palaeowind directions recorded from cross-strata of transverse, crescentic aeolian dunes of the Lower and Upper Units record dune migration under the influence of two dominant winds that blew to the southeast and northwest. Analysis of these palaeowind data in relation to assessment of regional palaeogeographic reconstructions for the period 1.6 to 1.5 Ga reveals a correlation between atmospheric circulation and land mass distribution. At this time the São Francisco Craton was located between the mid-latitudes and the equatorial zone. The wind regime determined from analysis of dip azimuths of cross-strata of the Lower Unit (1.6 to 1.54 Ga) are consistent with a palaeogeographic position between 25° to 35° S. Analysis of cross-strata dip azimuths of the Upper Unit indicate northwest-directed palaeowinds and a dominant monsoonal wind pattern from 1.54 to 1.5 Ga. During this time the large land mass of the São-Francisco-Congo and Siberian cratons drifted northwards through the equatorial zone from palaeolatitude 30° S to 30°N
Next-generation analysis of trypanosomatid genome stability and instability
No abstract available
Surface modification of starch based biomaterials by oxygen plasma or UV-irradiation
Radiation is widely used in biomaterials science for surface modification and sterilization. Herein, we describe the use of plasma and UV-irradiation to improve the biocompatibility of different starch-based blends in terms of cell adhesion and proliferation. Physical and chemical changes, introduced by the used methods, were evaluated by complementary techniques for surface analysis such as scanning electron microscopy, atomic force microscopy, contact angle analysis and X-ray photoelectron spectroscopy. The effect of the changed surface properties on the adhesion of osteoblast-like cells was studied by a direct contact assay. Generally, both treatments resulted in higher number of cells adhered to the modified surfaces. The importance of the improved biocompatibility resulting from the irradiation methods is further supported by the knowledge that both UV and plasma treatments can be used as cost-effective methods for sterilization of biomedical materials and devices.I. P. thanks the FCT for providing her a postdoctoral scholarship (SFRH/BPD/8491/2002). This work was partially supported by FCT, through funds from the POCTI and/or FEDER programs, The European Union funded STREP Project HIPPOCRATES (NNM-3-CT-2003-505758) and the European NoE EXPERTISSUES (NMP3-CT-2004-500283)
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