1,926 research outputs found

    An Analysis of the Efficacy of Wayside Hot-Box Detector Data

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    Wayside hot-box detectors (HBDs) are devices that are currently used to monitor bearing, axle, and brake temperatures as a way of assessing railcar component health and to indicate any possible overheating or abnormal operating conditions. Conventional hot-box detectors are set to alarm whenever a bearing is operating at a temperature that is 94.4°C (170°F) above ambient, or when there is a 52.8°C (95°F) temperature difference between two bearings that share an axle. These detectors are placed adjacent to the railway and utilize an infrared sensor in order to obtain temperature measurements. Bearings that trigger HBDs or display temperature trending behavior are removed from service for disassembly and inspection. Upon teardown, bearings that do not exhibit any discernible defects are labeled as “non-verified”. The latter may be due to the many factors that can affect the measurement of HBDs such as location of the infrared sensor and the class of the bearing among other environmental factors. A field test was performed along a route that is more than 483 km (300 mi) of track containing 21 wayside hot-box detectors. Two freight cars, one fully-loaded and one empty, and one instrumentation car pulled by a locomotive were used in this field test. A total of 16 bearings (14 Class F and 2 Class K) were instrumented with K-type bayonet thermocouples to provide continuous temperature measurement. The data collected from this field test were used to perform a systematic study in which the HBD IR sensor data were compared directly to the onboard thermocouple data. The analyses determined that, in general, HBDs tend to overestimate Class K bearing temperatures more frequently than Class F bearing temperatures. Additionally, the temperatures of some bearings were underestimated by as much as 47°C (85°F). Furthermore, the HBD data exhibited some false trending events that were not seen in temperature histories recorded by the bayonet thermocouples. The findings from the field test suggest that HBDs may inaccurately report bearing temperatures, which may contribute to the increased percentage of non-verified bearing removals. To further investigate the accuracy of the wayside detection systems, a dynamic test rig was designed and fabricated by the University Transportation Center for Railway Safety (UTCRS) research team at the University of Texas Rio Grande Valley (UTRGV). A mobile infrared sensor was developed and installed on the dynamic tester in order to mimic the measurement behavior of a HBD. The infrared temperature measurements were compared to contact thermocouple and bayonet temperature measurements taken on the bearing cup surface. The laboratory-acquired data were compared to actual field test data, and the analysis reveals that the trends are in close agreement. The large majority of temperature measurements taken using the IR sensor have been underestimated with a similar distribution to that of the data collected by the HBDs in field service

    Determination of the angular momentum of the Kerr black hole from equatorial geodesic motion

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    We present a method to determine the angular momentum of a black hole, based on observations of the trajectories of the bodies in the Kerr space-time. We use the Hamilton equations to describe the dynamics of a particle and present results for equatorial trajectories, obtaining an algebraic equation for the magnitude of the black hole's angular momentum. We tailor a numerical code to solve the dynamical equations and use it to generate synthetic data. We apply the method in some representative examples, obtaining the parameters of the trajectories as well as the black hole's angular momentum in good agreement with the input data.Comment: 24 page

    Formación E-learning para el profesorado de la Educación Secundaria Obligatoria de España para utilizar las Infraestructura de Datos Espaciales como un recurso educativo TIC.

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    Los avances en las nuevas Tecnologías de la Información y las Comunicaciones (TIC), evidentes en materias técnicas y científicas, influyen directa o indirectamente en el ámbito educativo. Sin embargo, contribuir desde los distintos niveles educativos a que los alumnos adquieran una preparación en el campo de las TIC requiere una formación previa del profesorado. Tanto desde el punto de vista teórico como práctico, el profesor tiene que conocer los nuevos recursos educativos TIC y las posibilidades de aplicación en aula a través de propuestas didácticas concretas y viables. En este contexto, se propone la utilización de las Infraestructuras de Datos Espaciales (IDE) como un recurso educativo TIC en aquellas materias de la Educación Secundaria Obligatoria que abordan contenidos directa o indirectamente relacionados con la Información Geográfica y las TIC. Para dar respuesta a la formación del profesorado en materia de IDE, tanto desde el punto de vista teórico como práctico, se ha desarrollado el proyecto basado en el Modelo de Diseño Instruccional ADDIE: “Formación e-learning para el profesorado de la Educación Secundaria Obligatoria para utilizar las IDE como recurso educativo”, a través de un Convenio de Colaboración entre el Instituto Geográfico Nacional de España y la Universidad Politécnica de Madrid

    Dental anomaly detection using intraoral photos via deep learning

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    Children with orofacial clefting (OFC) present with a wide range of dental anomalies. Identifying these anomalies is vital to understand their etiology and to discern the complex phenotypic spectrum of OFC. Such anomalies are currently identified using intra-oral exams by dentists, a costly and time-consuming process. We claim that automating the process of anomaly detection using deep neural networks (DNNs) could increase efficiency and provide reliable anomaly detection while potentially increasing the speed of research discovery. This study characterizes the use of` DNNs to identify dental anomalies by training a DNN model using intraoral photographs from the largest international cohort to date of children with nonsyndromic OFC and controls (OFC1). In this project, the intraoral images were submitted to a Convolutional Neural Network model to perform multi-label multi-class classification of 10 dental anomalies. The network predicts whether an individual exhibits any of the 10 anomalies and can do so significantly faster than a human rater can. For all but three anomalies, F1 scores suggest that our model performs competitively at anomaly detection when compared to a dentist with 8 years of clinical experience. In addition, we use saliency maps to provide a post-hoc interpretation for our model’s predictions. This enables dentists to examine and verify our model’s predictions.Fil: Ragodos, Ronilo. University of Iowa; Estados UnidosFil: Wang, Tong. University of Iowa; Estados UnidosFil: Padilla, Carmencita. University of the Philippines; FilipinasFil: Hecht, Jacqueline T.. University of Texas Health Science Center at Houston; Estados UnidosFil: Poletta, Fernando Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Orioli, Ieda Maria. Universidade Federal do Rio de Janeiro; BrasilFil: Buxó, Carmen J.. Universidad de Puerto Rico; Puerto RicoFil: Butali, Azeez. University of Iowa; Estados UnidosFil: Valencia Ramirez, Consuelo. Fundación Clínica Noel; ColombiaFil: Restrepo Muñeton, Claudia. Fundación Clínica Noel; ColombiaFil: Wehby, George. University of Iowa; Estados UnidosFil: Weinberg, Seth M.. University of Pittsburgh; Estados Unidos. University of Pittsburgh at Johnstown; Estados UnidosFil: Marazita, Mary L.. University of Pittsburgh at Johnstown; Estados Unidos. University of Pittsburgh; Estados UnidosFil: Moreno Uribe, Lina M.. University of Iowa; Estados UnidosFil: Howe, Brian J.. University of Iowa; Estados Unido

    PICALM modulates autophagy activity and tau accumulation.

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    Genome-wide association studies have identified several loci associated with Alzheimer's disease (AD), including proteins involved in endocytic trafficking such as PICALM/CALM (phosphatidylinositol binding clathrin assembly protein). It is unclear how these loci may contribute to AD pathology. Here we show that CALM modulates autophagy and alters clearance of tau, a protein which is a known autophagy substrate and which is causatively linked to AD, both in vitro and in vivo. Furthermore, altered CALM expression exacerbates tau-mediated toxicity in zebrafish transgenic models. CALM influences autophagy by regulating the endocytosis of SNAREs, such as VAMP2, VAMP3 and VAMP8, which have diverse effects on different stages of the autophagy pathway, from autophagosome formation to autophagosome degradation. This study suggests that the AD genetic risk factor CALM modulates autophagy, and this may affect disease in a number of ways including modulation of tau turnover.We are grateful for funding from a Wellcome Trust Principal Research Fellowship (D.C.R.), a Wellcome Trust/MRC Strategic Grant on Neurodegeneration (D.C.R., C.J.O’.K.), a Wellcome Trust Strategic Award to Cambridge Institute for Medical Research, Wellcome Trust Studentship (E.Z.), the Alzheimer’s disease Biomedical Research Unit and Addenbrooke’s Hospital, the Tau Consortium, a fellowship from University of Granada (A.L.R.), a V Foundation/Applebee’s Research Grant (D.S.W.) and NCI R01 CA 109281 (D.S.W.).This is the final published version. It is also available from Nature Publishing at http://www.nature.com/ncomms/2014/140922/ncomms5998/full/ncomms5998.html

    Smarcad1 mediates microbiota-induced inflammation in mouse and coordinates gene expression in the intestinal epithelium

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    Background How intestinal epithelial cells interact with the microbiota and how this is regulated at the gene expression level are critical questions. Smarcad1 is a conserved chromatin remodeling factor with a poorly understood tissue function. As this factor is highly expressed in the stem and proliferative zones of the intestinal epithelium, we explore its role in this tissue. Results Specific deletion of Smarcad1 in the mouse intestinal epithelium leads to colitis resistance and substantial changes in gene expression, including a striking increase of expression of several genes linked to innate immunity. Absence of Smarcad1 leads to changes in chromatin accessibility and significant changes in histone H3K9me3 over many sites, including genes that are differentially regulated upon Smarcad1 deletion. We identify candidate members of the gut microbiome that elicit a Smarcad1-dependent colitis response, including members of the poorly understood TM7 phylum. Conclusions Our study sheds light onto the role of the chromatin remodeling machinery in intestinal epithelial cells in the colitis response and shows how a highly conserved chromatin remodeling factor has a distinct role in anti-microbial defense. This work highlights the importance of the intestinal epithelium in the colitis response and the potential of microbial species as pharmacological and probiotic targets in the context of inflammatory diseases

    Whole Genome Sequence Analysis of Burkholderia contaminans FFH2055 Strain Reveals the Presence of Putative β-Lactamases

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    Burkholderia contaminans is a member of the Burkholderia cepacia complex (Bcc), a pathogen with increasing prevalence among cystic fibrosis (CF) patients and the cause of numerous outbreaks due to the use of contaminated commercial products. The antibiotic resistance determinants, particularly β-lactamases, have been poorly studied in this species. In this work, we explored the whole genome sequence (WGS) of a B. contaminans isolate (FFH 2055) and detected four putative β-lactamase-encoding genes. In general, these genes have more than 93% identity with β-lactamase genes found in other Bcc species. Two β-lactamases, a class A (Pen-like, suggested name PenO) and a class D (OXA-like), were further analyzed and characterized. Amino acid sequence comparison showed that Pen-like has 82% and 67% identity with B. multivorans PenA and B. pseudomallei PenI, respectively, while OXA-like displayed strong homology with class D enzymes within the Bcc, but only 22–44% identity with available structures from the OXA family. PCR reactions designed to study the presence of these two genes revealed a heterogeneous distribution among clinical and industrial B. contaminans isolates. Lastly, bla PenO gene was cloned and expressed into E. coli to investigate the antibiotic resistance profile and confers an extended-spectrum β-lactamase (ESBL) phenotype. These results provide insight into the presence of β-lactamases in B. contaminans, suggesting they play a role in antibiotic resistance of these bacteria.Fil: Degrossi, José J.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Merino, Cindy. University Fullerton; Estados UnidosFil: Isasmendi, Adela M.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Ibarra, Lorena M.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Collins, Chelsea. University Fullerton; Estados UnidosFil: Bo, Nicolás E.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Papalia, Mariana Andrea. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Fernandez, Jennifer S.. University Fullerton; Estados UnidosFil: Hernandez, Claudia M.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Papp Wallace, Krisztina M.. Case Western Reserve University; Estados UnidosFil: Bonomo, Robert A.. Case Western Reserve University; Estados UnidosFil: Vazquez, Miryam S.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Power, Pablo. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Ramirez, María S.. University Fullerton; Estados Unido

    SALL1 enforces microglia-specific DNA binding and function of SMADs to establish microglia identity

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    Spalt-like transcription factor 1 (SALL1) is a critical regulator of organogenesis and microglia identity. Here we demonstrate that disruption of a conserved microglia-specific super-enhancer interacting with the Sall1 promoter results in complete and specific loss of Sall1 expression in microglia. By determining the genomic binding sites of SALL1 and leveraging Sall1 enhancer knockout mice, we provide evidence for functional interactions between SALL1 and SMAD4 required for microglia-specific gene expression. SMAD4 binds directly to the Sall1 super-enhancer and is required for Sall1 expression, consistent with an evolutionarily conserved requirement of the TGFβ and SMAD homologs Dpp and Mad for cell-specific expression of Spalt in the Drosophila wing. Unexpectedly, SALL1 in turn promotes binding and function of SMAD4 at microglia-specific enhancers while simultaneously suppressing binding of SMAD4 to enhancers of genes that become inappropriately activated in enhancer knockout microglia, thereby enforcing microglia-specific functions of the TGFβ–SMAD signaling axis.</p

    Primer implante coclear exitoso en América Latina después de ototoxicidad severa inducida por aminoglucósidos en un paciente peruano curado de una tuberculosis extremadamente resistente.

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    Introduction: Multidrug-resistant tuberculosis is a significant public health problem for which drugs are used with many adverse effects. Among the devastating consequences of these diseases, there is a wide variation in the incidence of ototoxicity and hearing loss in patients with multidrug-resistant and extremely resistant tuberculosis. Cochlear implants may be indicated in patients with unilateral/severe bilateral hearing loss with no benefit from conventional hearing aids, but their use in patients with tuberculosis is rare. Case report: We present the first case of a right unilateral cochlear implant performed on a 34-year-old Peruvian patient who presented profound sensorineural hearing loss of cochlear origin. Conclusion: Cochlear implant surgery is an essential milestone in the treatment of patients with auditory sequelae of tuberculosis treatment. Close monitoring of possible complications of tuberculosis treatment should be strengthened in countries with a high incidence of multidrug-resistant and extremely resistant tuberculosis.Introducción: La tuberculosis multidrogorresistente es un importante problema de salud pública para el que se utilizan fármacos con múltiples efectos adversos. Entre las devastadoras consecuencias de estas enfermedades, existe una amplia variación en la incidencia de ototoxicidad y pérdida auditiva en pacientes con tuberculosis multirresistente y extremadamente resistente. Los implantes cocleares pueden estar indicados en pacientes con pérdida auditiva unilateral/bilateral severa sin beneficio de los audífonos convencionales, pero su uso en pacientes con tuberculosis es raro. Reporte de un caso: Presentamos el primer caso de implante coclear unilateral derecho realizado a un paciente peruano de 34 años que presentaba hipoacusia neurosensorial profunda de origen coclear. Conclusión: La cirugía de implante coclear es un hito fundamental en el tratamiento de los pacientes con secuelas auditivas del tratamiento de la tuberculosis. Se debe fortalecer la vigilancia estrecha de las posibles complicaciones del tratamiento de la tuberculosis en los países con una alta incidencia de tuberculosis multirresistente y extremadamente resistente

    XUE. Molecular inventory in the inner region of an extremely irradiated Protoplanetary Disk

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    We present the first results of the eXtreme UV Environments (XUE) James Webb Space Telescope (JWST) program, that focuses on the characterization of planet forming disks in massive star forming regions. These regions are likely representative of the environment in which most planetary systems formed. Understanding the impact of environment on planet formation is critical in order to gain insights into the diversity of the observed exoplanet populations. XUE targets 15 disks in three areas of NGC 6357, which hosts numerous massive OB stars, among which some of the most massive stars in our Galaxy. Thanks to JWST we can, for the first time, study the effect of external irradiation on the inner (<10< 10 au), terrestrial-planet forming regions of proto-planetary disks. In this study, we report on the detection of abundant water, CO, CO2_2, HCN and C2_2H2_2 in the inner few au of XUE 1, a highly irradiated disk in NGC 6357. In addition, small, partially crystalline silicate dust is present at the disk surface. The derived column densities, the oxygen-dominated gas-phase chemistry, and the presence of silicate dust are surprisingly similar to those found in inner disks located in nearby, relatively isolated low-mass star-forming regions. Our findings imply that the inner regions of highly irradiated disks can retain similar physical and chemical conditions as disks in low-mass star-forming regions, thus broadening the range of environments with similar conditions for inner disk rocky planet formation to the most extreme star-forming regions in our Galaxy.Comment: Accepted for publication in ApJ Letters. 20 pages, 7 figure
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