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A fundamental problem in neuroscience is how neurons select for their many inputs. A common assumption is that a neuron's selectivity is largely explained by differences in excitatory synaptic input weightings. Here we describe another solution to this important problem. We show that within the first order visual thalamus, the type of inhibition provided by thalamic interneurons has the potential to alter the input selectivity of thalamocortical neurons. To do this, we developed conductance injection protocols to compare how different types of synchronous and asynchronous GABA release influence thalamocortical excitability in response to realistic patterns of retinal ganglion cell input. We show that the asynchronous GABA release associated with tonic inhibition is particularly efficient at maintaining information content, ensuring that thalamocortical neurons can distinguish between their inputs. We propose a model where alterations in GABA release properties results in rapid changes in input selectivity without requiring structural changes in the network.
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Coccidioidomycosis is a fungal disease in arid regions of the United States that is predicted to expand with climate change. Cases in military personnel and military working dogs (MWDs) impact personnel readiness and result in healthcare costs. To examine Coccidioides exposure among MWDs, 276 banked serum samples were retrieved from dogs housed in California, Texas, Arizona, New Mexico, Nevada, and Utah. Using gel immunodiffusion, six (2.1%) specimens were IgG-positive and three (1.1%) were equivocally IgM-positive. The IgG-positive samples were from Arizona (2 [prevalence 8.0%]) and California (4 [3.7%]). These data will guide future efforts to study MWDs as sentinels for human coccidioidomycosis.
This study aimed to determine the prevalence of exposure to coccidioidomycosis, the cause of Valley Fever in both humans and animals, among military working dogs (MWDs)located in endemic regions of the United States. The data will be used to guide efforts to study MWDs as sentinels for human disease.
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Coccidioides , Coccidioidomicosis , Estados Unidos/epidemiología , Humanos , Animales , Perros , Coccidioidomicosis/epidemiología , Coccidioidomicosis/veterinaria , Coccidioidomicosis/microbiología , Perros de Trabajo , Arizona/epidemiología , Inmunoglobulina GRESUMEN
INTRODUCTION: U.S. Army Veterinary Corps provides highly skilled and adaptive veterinary professionals to protect and improve the health of people and animals while enhancing readiness throughout the DOD. Army veterinarians must be trained and credentialed for critical tasks within the animal health and food protection missions across all components. The Veterinary Metrics Division in the U.S. Army Public Health Center's Veterinary Services and Public Health Sanitation Directorate is responsible for tracking readiness metrics of Army veterinarians and maintains a robust online Readiness Metrics Platform. Readiness targets were developed based on trends in readiness platform data, input of senior veterinary subject matter experts, and feedback from the field. To date, no data have been published describing the cases presented to DOD-owned Veterinary Treatment Facilities (VTFs). Without capturing and codifying the types of cases that present to the VTF and comparing to cases typically encountered during deployments, it is difficult to determine whether the VTF serves as an adequate readiness platform. In this study, we compare a representative random sample of non-wellness VTF patient encounters in garrison to cases reported from two different combat zones to determine if the VTF is a suitable clinical readiness platform. MATERIALS AND METHODS: Multiple data sources, including pre-existing published data and new data extracted from multiple sources, were used. The Iraq 2009-2010 dataset includes data collected from a Medical Detachment, Veterinary Service Support (MDVSS) deployed to Iraq from January 5, 2009 through August 23, 2010. The Iraq 2003-2007 dataset originated from a retrospective cross-sectional survey that included database and medical record abstraction. The Afghanistan 2014-2015 dataset includes data collected from the MDVSS deployed to Afghanistan from June 2014 to March 2015. Working dog veterinary encounter data were manually extracted from monthly and daily clinical reports. Data for the Garrison 2016-2018 dataset were extracted from the Remote Online Veterinary Record. A random representative sample of government-owned animal (GOA) and privately owned animal (POA) encounters seen across all DOD-owned VTFs from June 2016 to May 2018 were selected. RESULTS: We found that animals present to the VTF for a wide variety of illnesses. Overall, the top 10 encounter categories (90.3%) align with 84.2%, 92.4%, and 85.9% of all the encounter types seen in the three combat zone datasets. Comparing these datasets identifies potential gaps in readiness training relying solely on the VTF, especially in the areas of traumatic and combat-related injuries. CONCLUSIONS: Ultimately, the success of the DOD Veterinary Services Animal Health mission depends on both the competence and confidence of the individual Army veterinarian. As the MHS transitions and DOD Veterinary Services continues to transform emphasizing readiness through a public health and prevention-based Army medicine approach, Army veterinarians must strike a delicate balance to continue to provide comprehensive health care to GOAs and POAs in the VTFs. Leaders at all levels must recognize the roles VTFs play in overall public health readiness and disease prevention through the proper appropriation and allocation of resources while fostering the development, confidence, and competence of Army veterinarians training within these readiness platforms.
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The ubiquitous presence of inhibitory interneurons in the thalamus of primates contrasts with the sparsity of interneurons reported in mice. Here, we identify a larger than expected complexity and distribution of interneurons across the mouse thalamus, where all thalamic interneurons can be traced back to two developmental programmes: one specified in the midbrain and the other in the forebrain. Interneurons migrate to functionally distinct thalamocortical nuclei depending on their origin: the abundant, midbrain-derived class populates the first and higher order sensory thalamus while the rarer, forebrain-generated class is restricted to some higher order associative regions. We also observe that markers for the midbrain-born class are abundantly expressed throughout the thalamus of the New World monkey marmoset. These data therefore reveal that, despite the broad variability in interneuron density across mammalian species, the blueprint of the ontogenetic organisation of thalamic interneurons of larger-brained mammals exists and can be studied in mice.
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Linaje de la Célula , Interneuronas , Tálamo/crecimiento & desarrollo , Animales , Callithrix , Movimiento Celular , Femenino , Neuronas GABAérgicas , Regulación del Desarrollo de la Expresión Génica , Hibridación in Situ , Masculino , Mesencéfalo/crecimiento & desarrollo , Ratones , Ratones Transgénicos , Prosencéfalo/crecimiento & desarrollo , Tálamo/citologíaRESUMEN
This case of sarcoidosis mimicking metastatic breast cancer serves as a reminder of the need to consider differential diagnoses even when the clinical scenario and imaging findings are highly suggestive of metastases.
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BACKGROUND: Despite a paucity of evidence to support a multitude of educational innovations, curricular leaders are pressured to find innovative solutions to better prepare medical students for an evolving twenty-first century health care system. As part of this effort, this study directly compared student-rated effectiveness scores of six different learning modalities. METHODS: Study participants included 286 medical students enrolled in the second-year rheumatology core at a single academic medical center between 2013 and 2017. Students were surveyed at the end of the core with a 15-item questionnaire, and student perceived effectiveness of six different learning modalities were compared. RESULTS: The modality that outperformed all others was Live Patient Encounters (LPE), with significantly higher student-rated effectiveness scores when compared to the referent modality of Problem-Based Learning (PBL). Using a 5-point Likert scale with responses ranging from "not effective" to "highly effective," LPE received a mean effectiveness score of 4.77 followed by Augenblick (4.21), PBL (4.11), Gout Racer video game (3.49), Rheumatology Remedy e-module (3.49), and simulation knee injection (3.09). CONCLUSIONS: Technologically advanced novel learning strategies were outperformed in this study by the more traditional active learning modality of LPE. This finding highlights the importance of testing innovative learning strategies at the level of the learner. Three additional conclusions can be drawn from this result. First, conflation of technology with innovation may lead to a myopic view of educational reform. Second, human factors seem to be responsible for the success of LPE and may have far-reaching educational rewards. Third, further applications of LPE should be tested in non-rheumatologic curricula. The relevance of this study is innately tied to the humanities-based application. While a formal qualitative analysis was not performed in this study, preliminary results suggest that live, structured patient interactions in the pre-clinical years of medical education may not only promote the learning of important educational objectives but also foster professional development, empathy, reflection, leadership, agency, and interpersonal skills. This "win-win" scenario (if true) would stand out as a rarity among strategic educational initiatives.
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Educación de Pregrado en Medicina/organización & administración , Aprendizaje Basado en Problemas/organización & administración , Reumatología/educación , Humanos , Encuestas y CuestionariosRESUMEN
Temperature variability is a major driver of ecological pattern, with recent changes in average and extreme temperatures having significant impacts on populations, communities and ecosystems. In the marine realm, very few experiments have manipulated temperature in situ, and current understanding of temperature effects on community dynamics is limited. We developed new technology for precise seawater temperature control to examine warming effects on communities of bacteria, microbial eukaryotes (protists) and metazoans. Despite highly contrasting phylogenies, size spectra and diversity levels, the three community types responded similarly to seawater warming treatments of +3°C and +5°C, highlighting the critical and overarching importance of temperature in structuring communities. Temperature effects were detectable at coarse taxonomic resolutions and many taxa responded positively to warming, leading to increased abundances at the community-level. Novel field-based experimental approaches are essential to improve mechanistic understanding of how ocean warming will alter the structure and functioning of diverse marine communities.
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Biota , Ecosistema , Agua de Mar , Temperatura , Animales , Bacterias/clasificación , Filogenia , Microbiología del AguaRESUMEN
Beam combining of phase-modulated kilowatt fiber amplifiers has generated considerable interest recently. We describe in the time domain how stimulated Brillouin scattering (SBS) is generated in an optical fiber under phase-modulated laser conditions, and we analyze different phase modulation techniques. The temporal and spatial evolutions of the acoustic phonon, laser, and Stokes fields are determined by solving the coupled three-wave interaction system. Numerical accuracy is verified through agreement with the analytical solution for the un-modulated case and through the standard photon conservation relation for counter-propagating optical fields. As a test for a modulated laser, a sinusoidal phase modulation is examined for a broad range of modulation amplitudes and frequencies. We show that, at high modulation frequencies, our simulations agree with the analytical results obtained from decomposing the optical power into its frequency components. At low modulation frequencies, there is a significant departure due to the appreciable cross talk among the laser and Stokes sidebands. We also examine SBS suppression for a white noise source and show significant departures for short fibers from analytically derived formulas. Finally, SBS suppression through the application of pseudo-random bit sequence modulation is examined for various patterns. It is shown that for a fiber length of 9 m the patterns at or near n=7 provide the best mitigation of SBS with suppression factors approaching 17 dB at a modulation frequency of 5 GHz.
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INTRODUCTION: The National Institutes of Health provided grants to the Oregon Health & Science University (OHSU) and 14 other allopathic academic health centers for the development of curricula in complementary and alternative medicine (CAM). A key component of the curriculum evaluation for OHSU was provided by a survey assessing attitudes toward CAM and selected personality characteristics of entering students in chiropractic, naturopathic, Oriental, and allopathic medicine in the Pacific Northwest and Upper Midwest. METHODS: A survey containing a variety of assessments of attitudes toward CAM and the personality traits of adventurousness and tolerance to ambiguity was administered to students entering four Portland, Oregon doctoral-level health professional schools and an allopathic medical school in the Upper Midwest (University of Nebraska College of Medicine) during the 2004-2005 academic year. RESULTS: Students of naturopathy (n = 63) and Oriental Medicine (n = 71) were the most "CAM positive," adventurous and tolerant of ambiguity, and Midwestern allopathic medical students (n = 58) the least. In general, chiropractic students (n = 89) and allopathic medical students from the Pacific Northwest (n = 95) were intermediate in CAM attitudes between these two groups (all p < 0.05). Female students were more "CAM positive" in all schools compared to male students. CONCLUSIONS: Students have high levels of interest in CAM upon entrance to their schools. Health professional discipline, geographic location, personality qualities, and gender appear to influence CAM attitudes in entering students.
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Competencia Clínica , Terapias Complementarias/educación , Educación Médica/organización & administración , Estudiantes de Medicina/estadística & datos numéricos , Centros Médicos Académicos/organización & administración , Adulto , Análisis de Varianza , Actitud del Personal de Salud , Terapias Complementarias/estadística & datos numéricos , Curriculum , Medicina Basada en la Evidencia/educación , Femenino , Humanos , Persona de Mediana Edad , Oregon , Innovación Organizacional , Evaluación de Programas y Proyectos de SaludRESUMEN
A semianalytical approach to the problem of determining inherent optical properties from satellite and in situ ocean color data is presented. The model uses empirically derived spectral slopes between neighboring wavebands in combination with radiative transfer modeling to determine the spectral absorption (alpha) and backscatter (b(b)); these values are then further decomposed into absorption due to phytoplankton, detrital, and colored dissolved organic matter components. When compared with over 400 in situ data points the model makes good retrievals of the total absorption and backscatter across the entire spectrum, with regression slopes close to unity, little or no bias, high percentage of variance explained, and low rms errors.
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Color , Colorimetría/métodos , Modelos Químicos , Modelos Moleculares , Agua de Mar/química , Análisis Espectral/métodos , Simulación por Computador , Océanos y Mares , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Field determinations of the remote sensing reflectance signal are necessary to validate ocean color satellite sensors. The measurement of the above-water downwelling irradiance signal Ed(0+) is commonly made with a reference plaque of a known reflectance. The radiance reflected by the plaque (L(dspec)) can be used to determine Ed(0+) if the plaque is assumed to be near Lambertian. To test this assumption, basic experiments were conducted on a boat under changing sky conditions (clear, cloudy, covered) and with different configurations for simultaneous measurements of L(dspec) and Ed(0+). For all measurement configurations, results were satisfactory under a clear sky. Under cloudy or covered skies, shadow effects on the plaque induced errors up to 100% in the determination of Ed(0+). An appropriate measurement configuration was defined, which enabled Ed(0+) to be determined with an accuracy of better than +/- 15% regardless of the sky conditions.
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We show an experimental proof of concept for a nonresonant recirculation method to increase the conversion efficiency of second-harmonic generation (SHG) with type II phase matching. As much as a factor-of-4 efficiency increase compared with that of single-pass SHG is possible, provided that the recirculation length is within the coherence length of the pump laser. Nonresonant recirculating SHG may be valuable in systems in which intracavity doubling is not practicable, such as high-power cw bulk solid-state or fiber lasers.
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A 20-W all-solid-state continuous-wave single-frequency source tuned to the sodium D2a line at 589.159 nm has been developed for adaptive optical systems. This source is based on sum-frequency mixing two injection-locked Nd:YAG lasers in lithium triborate in a doubly resonant external cavity. Injection locking the Nd:YAG lasers not only ensures single-frequency operation but also allows the use of a single rf local oscillator for Pound-Drever-Hall locking both the injection-slave and the sum-frequency cavities. We observe power-conversion efficiencies in excess of 55% and a linearly polarized diffraction-limited output tunable across the sodium D2 line (589.156 to 589.160 nm) with no change in output power and with high amplitude and pointing stability.
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A configuration of N coated mirrors or mirror pairs is described that has the potential to coherently combine 2N single-frequency phase-locked diffraction-limited polarized optical beams to form a single diffraction-limited beam. The application to beam combination of fiber amplifiers is discussed.
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OBJECTIVE: To compare the efficacy of combination therapy with methotrexate (MTX) and hydroxychloroquine (HCQ), MTX and sulfasalazine (SSZ), and MTX, HCQ, and SSZ in patients with rheumatoid arthritis (RA). METHODS: RA patients (n = 171) who had not previously been treated with combinations of the study medications were randomized to receive 1 of the 3 treatment combinations in this 2-year, double-blind, placebo-controlled protocol. HCQ was given at a dosage of 200 mg twice a day. The dosage of MTX was accelerated from 7.5 mg/week to 17.5 mg/week in all patients who were not in remission. Similarly, the dosage of SSZ was escalated from 500 mg twice a day to 1 gm twice a day in patients who were not in remission. The primary end point of the study was the percentage of patients who had a 20% response to therapy according to the American College of Rheumatology (ACR) criteria at 2 years. RESULTS: Intent-to-treat analysis revealed that patients receiving the triple combination responded best, with 78% achieving an ACR 20% response at 2 years, compared with 60% of those treated with MTX and HCQ (P = 0.05) and 49% of those treated with MTX and SSZ (P = 0.002). Similar trends were seen for the ACR 50% response, with 55%, 40%, and 29% of patients in the 3 treatment groups, respectively, achieving these results at 2 years (P = 0.005 for the triple combination group versus the MTX and SSZ group). All combination treatments were well-tolerated. Fourteen patients (evenly distributed among the 3 groups) withdrew from the protocol because of symptoms that were potentially related to the study medication. CONCLUSION: The triple combination of MTX, SSZ, and HCQ is well-tolerated, and its efficacy is superior to that of the double combination of MTX and SSZ and is marginally superior to that of the double combination of MTX and HCQ.
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Antirreumáticos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , Hidroxicloroquina/administración & dosificación , Metotrexato/administración & dosificación , Sulfasalazina/administración & dosificación , Adulto , Anciano , Antirreumáticos/efectos adversos , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Hidroxicloroquina/efectos adversos , Masculino , Metotrexato/efectos adversos , Persona de Mediana Edad , Sulfasalazina/efectos adversos , Resultado del TratamientoRESUMEN
Blooms of the phytoplankton coccolithophorid Emiliania huxleyi can cause significant changes to both the inherent and the apparent optical properties within an oceanic column. Measurements made within such a bloom off the southwestern coast of England during July 1999 are reported. The multiple scattering properties of the bloom prevented accurate retrieval of absorption (a) and attenuation (c) coefficients with a WETLabs ac-9. Upwelling radiance measurements were similarly affected by the bloom, which caused the sensors to saturate. An optical model has been developed that gives close agreement with the in situ optics when it is used as input to the Hydrolight radiative-transfer model.