238 research outputs found

    The ultracool dwarf DENIS-P J104814.7-395606. Chromospheres and coronae at the low-mass end of the main-sequence

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    We have obtained an XMM-Newton observation and a broad-band spectrum from the ultraviolet to the near infrared with X-Shooter for one of the nearest M9 dwarfs, DENIS-P J1048-3956 (4pc). We integrate these data by a compilation of activity parameters for ultracool dwarfs from the literature with the aim to advance our understanding of these objects by comparing them to early-M type dwarf stars and the Sun. Our deep XMM-Newton observation has led to the first X-ray detection of DENIS-P J1048-3956 (log Lx = 25.1) as well as the first measurement of its V band brightness (V = 17.35mag). Flux-flux relations between X-ray and chromospheric activity indicators are here for the first time extended into the regime of the ultracool dwarfs. The approximate agreement of DENIS-P J1048-3956 and other ultracool dwarfs with flux-flux relations for early-M dwarfs suggests that the same heating mechanisms work in the atmospheres of ultracool dwarfs, albeit weaker as judged from their lower fluxes. The observed Balmer decrements of DENIS-P J1048-3956 are compatible with optically thick plasma in LTE at low, nearly photospheric temperature or optically thin LTE plasma at 20000K. Describing the decrements with CaseB recombination requires different emitting regions for Halpha and the higher Balmer lines. The high observed Halpha/Hbeta flux ratio is also poorly fitted by the optically thin models. We derive a similarly high value for the Halpha/Hbeta ratio of vB10 and LHS2065 and conclude that this may be a characteristic of ultracool dwarfs. We add DENIS-P J1048-3956 to the list of ultracool dwarfs detected in both the radio and the X-ray band. The Benz-Guedel relation between radio and X-ray luminosity of late-type stars is well-known to be violated by ultracool dwarfs. We speculate on the presence of two types of ultracool dwarfs with distinct radio and X-ray behavior.Comment: accepted for publication in Astronomy & Astrophysic

    TRY plant trait database - enhanced coverage and open access

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    Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Regional prediction of landslide hazard using probability analysis of intense rainfall in the Hoa Binh province, Vietnam.

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    The main objective of this study is to assess regional landslide hazards in the Hoa Binh province of Vietnam. A landslide inventory map was constructed from various sources with data mainly for a period of 21 years from 1990 to 2010. The historic inventory of these failures shows that rainfall is the main triggering factor in this region. The probability of the occurrence of episodes of rainfall and the rainfall threshold were deduced from records of rainfall for the aforementioned period. The rainfall threshold model was generated based on daily and cumulative values of antecedent rainfall of the landslide events. The result shows that 15-day antecedent rainfall gives the best fit for the existing landslides in the inventory. The rainfall threshold model was validated using the rainfall and landslide events that occurred in 2010 that were not considered in building the threshold model. The result was used for estimating temporal probability of a landslide to occur using a Poisson probability model. Prior to this work, five landslide susceptibility maps were constructed for the study area using support vector machines, logistic regression, evidential belief functions, Bayesian-regularized neural networks, and neuro-fuzzy models. These susceptibility maps provide information on the spatial prediction probability of landslide occurrence in the area. Finally, landslide hazard maps were generated by integrating the spatial and the temporal probability of landslide. A total of 15 specific landslide hazard maps were generated considering three time periods of 1, 3, and 5 years

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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    Excess degassing drives long-term volcanic unrest at Nevado del Ruiz

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    This study combines volcanic gas compositions, SO2 flux and satellite thermal data collected at Nevado del Ruiz between 2018 and 2021. We find the Nevado del Ruiz plume to have exhibited relatively steady, high CO2 compositions (avg. CO2/ST ratios of 5.4 ± 1.9) throughout. Our degassing models support that the CO2/ST ratio variability derives from volatile exsolution from andesitic magma stored in the 1–4 km depth range. Separate ascent of CO2-rich gas bubbles through shallow (< 1 km depth), viscous, conduit resident magma causes the observed excess degassing. We infer that degassing of ~ 974 mm3 of shallow (1–4 km) stored magma has sourced the elevated SO2 degassing recorded during 2018–2021 (average flux ~ 1548 t/d). Of this, only < 1 mm3 of magma have been erupted through dome extrusion, highlighting a large imbalance between erupted and degassed magma. Escalating deep CO2 gas flushing, combined with the disruption of passive degassing, through sudden accumulation and pressurization of bubbles due to lithostatic pressure, may accelerate volcanic unrest and eventually lead to a major eruption

    Surveillance for Invasive Meningococcal Disease in Children, US–Mexico Border, 2005–20081

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    We reviewed confirmed cases of pediatric invasive meningococcal disease in Tijuana, Mexico, and San Diego County, California, USA, during 2005–2008. The overall incidence and fatality rate observed in Tijuana were similar to those found in the US, and serogroup distribution suggests that most cases in Tijuana are vaccine preventable

    Evaluating SKI as a candidate gene for non-syndromic cleft lip with or without cleft palate

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    Non-syndromic cleft lip with or without cleft palate (NSCL/P) is one of the most common of all congenital malformations and has a multifactorial etiology. Findings in mice suggest that the v-ski sarcoma viral oncogene homolog (SKI) gene is a candidate gene for orofacial clefting. In humans, a significant association between rs2843159 within SKI and NSCL/P has been reported in patients from the Philippines and South America. In the South American patients, the association was driven by the subgroup of patients with non-syndromic cleft lip only (NSCLO). Here we investigated the association with rs2843159 in a Mayan Mesoamerican population (172 NSCL/P patients and 366 controls). In addition, we analyzed the phenotypic subgroups NSCLO and non-syndromic cleft of lip and palate (NSCLP). A trend towards association between rs2843159 and NSCL/P was observed in the Mayan cohort (P = 0.097), and we found a stronger association in the NSCLP subgroup (P = 0.072) despite a limited sample size. To investigate whether other common variants within the SKI gene contribute to NSCL/P susceptibility in European and Asian populations, we also analyzed genotypic data from two recent genome-wide association studies using set-based statistical approaches. These analyses detected a trend toward association in the European population. Our data provide limited support for the hypothesis that common SKI variants are susceptibility factors for NSCL/P

    Integrated microbiota–host–metabolome approaches reveal adaptive ruminal changes to prolonged high-grain feeding and phytogenic supplementation in cattle

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    Diets rich in readily fermentable carbohydrates primarily impact microbial composition and activity, but can also impair the ruminal epithelium barrier function. By combining microbiota, metabolome, and gene expression analysis, we evaluated the impact of feeding a 65% concentrate diet for 4 weeks, with or without a phytogenic feed additive (PFA), on the rumen ecosystem of cattle. The breaking point for rumen health seemed to be the second week of high grain (HG) diet, with a dysbiosis characterized by reduced alpha diversity. While we did not find changes in histological evaluations, genes related with epithelial proliferation (IGF-1, IGF-1R, EGFR, and TBP) and ZO-1 were affected by the HG feeding. Integrative analyses allowed us to define the main drivers of difference for the rumen ecosystem in response to a HG diet, identified as ZO-1, MyD88, and genus Prevotella 1. PFA supplementation reduced the concentration of potentially harmful compounds in the rumen (e.g. dopamine and 5-aminovaleric acid) and increased the tolerance of the epithelium toward the microbiota by altering the expression of TLR-2, IL-6, and IL-10. The particle-associated rumen liquid microbiota showed a quicker adaptation potential to prolonged HG feeding compared to the other microenvironments investigated, especially by the end of the experiment

    Electronic health records and patient registries in medical oncology departments in Spain

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    We aimed to evaluate the current situation of electronic health records (EHRs) and patient registries in the oncology departments of hospitals in Spain. This was a cross-sectional study conducted from December 2018 to September 2019. The survey was designed ad hoc by the Outcomes Evaluation and Clinical Practice Section of the Spanish Society of Medical Oncology (SEOM) and was distributed to all head of medical oncology department members of SEOM. We invited 148 heads of oncology departments, and 81 (54.7%) questionnaires were completed, with representation from all 17 Spanish autonomous communities. Seventy-seven (95%) of the respondents had EHRs implemented at their hospitals; of them, over 80% considered EHRs to have a positive impact on work organization and clinical practice, and 73% considered that EHRs improve the quality of patient care. In contrast, 27 (35.1%) of these respondents felt that EHRs worsened the physician-patient relationship and conveyed an additional workload (n = 29; 37.6%). Several drawbacks in the implementation of EHRs were identified, including the limited inclusion of information on both outpatients and inpatients, information recorded in free text data fields, and the availability of specific informed consent. Forty-six (56.7%) respondents had patient registries where they recorded information from all patients seen in the department. Our study indicates that EHRs are almost universally implemented in the hospitals surveyed and are considered to have a positive impact on work organization and clinical practice. However, EHRs currently have several drawbacks that limit their use for investigational purposes. Not applicable The online version contains supplementary material available at 10.1007/s12094-021-02614-9

    The nearest young moving groups

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    The latest results in the research of forming planetary systems have led several authors to compile a sample of candidates for searching for planets in the vicinity of the sun. Young stellar associations are indeed excellent laboratories for this study, but some of them are not close enough to allow the detection of planets through adaptive optics techniques. However, the existence of very close young moving groups can solve this problem. Here we have compiled the members of the nearest young moving groups, as well as a list of new candidates from our catalogue of late-type stars possible members of young stellar kinematic groups, studying their membership through spectroscopic and photometric criteria.Comment: Latex file with 16 pages, 4 figures. Available at http://www.ucm.es/info/Astrof/invest/actividad/skg/skg_sag.html Accepted for publication in: The Astrophysical Journal (ApJ
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