434 research outputs found

    HNX/SuperTIGER Silicon Strip Detector Response to Nuclei in Lead Primary and Fragmented Test Beams

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    The response to 150 GeV/nuc primary lead (^(208)Pb) and fragmented (A/Z=2.4, 2.2, 2.0) beams measured a silicon strip detector, designed for use in the Heavy Nuclei eXplorer (HNX) and an upgrade of the Super Trans-Iron Galactic Element Recorder (SuperTIGER) balloon experiment, was evaluated in a CERN test beam (H8A) during Nov - Dec 2018. The 500 μm thick, single-sided silicon detectors have 32 DC-coupled strips with 3 mm pitch on the junction side with 9.6×9.6 cm^2 active area. Discrete charge-preamplifiers and shaping amplifiers were used to read out the ohmic and junction side signals simultaneously using the SuperTIGER DAQ system. We report on the response in a configuration where all 32 strips were joined and read out together. The strip detector-under-test was situated between planar silicon detectors, which provided the charge selection as well as a comparison of the measured response of each detector. The combined data set shows excellent charge resolution and finely resolved elemental peaks from helium (Z=2) through lead (Z=82). In this paper, we provide a description of the test beam experiment and the results of the charge resolution analysis

    STEREO Observations of Energetic Neutral Hydrogen Atoms During the 2006 December 5 Solar Flare

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    We report the discovery of energetic neutral hydrogen atoms (ENAs) emitted during the X9 solar event of 2006 December 5. Beginning ~1 hr following the onset of this E79 flare, the Low Energy Telescopes (LETs) on both the STEREO A and B spacecraft observed a sudden burst of 1.6-15 MeV protons beginning hours before the onset of the main solar energetic particle event at Earth. More than 70% of these particles arrived from a longitude within ±10° of the Sun, consistent with the measurement resolution. The derived emission profile at the Sun had onset and peak times remarkably similar to the GOES soft X-ray profile and continued for more than an hour. The observed arrival directions and energy spectrum argue strongly that the particle events < 5 MeV were due to ENAs. To our knowledge, this is the first reported observation of ENA emission from a solar flare/coronal mass ejection. Possible origins for the production of ENAs in a large solar event are considered. We conclude that the observed ENAs were most likely produced in the high corona and that charge-transfer reactions between accelerated protons and partially stripped coronal ions are an important source of ENAs in solar events

    Observations and Interpretations of Energetic Neutral Hydrogen Atoms from the December 5, 2006 Solar Event

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    We discuss recently reported observations of energetic neutral hydrogen atoms (ENAs) from an X9 solar flare/coronal mass ejection event on 5 December 2006, located at E79. The observations were made by the Low Energy Telescopes (LETs) on STEREO A and B. Prior to the arrival of the main solar energetic particle (SEP) event at Earth, both LETs observed a sudden burst of 1.6 to 15 MeV energetic neutral hydrogen atoms produced by either flare or shock-accelerated protons. RHESSI measurements of the 2.2-MeV γ-ray line provide an estimate of the number of interacting flare-accelerated protons in this event, which leads to an improved estimate of ENA production by flare-accelerated protons. Taking into account ENA losses, we find that the observed ENAs must have been produced in the high corona at heliocentric distances ≥ 2 solar radii. Although there are no CME images from this event, it is shown that CME-shock-accelerated protons can, in principle, produce a time-history consistent with the observations

    HNX/SuperTIGER Silicon Strip Detector Response to Nuclei in Lead Primary and Fragmented Test Beams

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    The response to 150 GeV/nuc primary lead (^(208)Pb) and fragmented (A/Z=2.4, 2.2, 2.0) beams measured a silicon strip detector, designed for use in the Heavy Nuclei eXplorer (HNX) and an upgrade of the Super Trans-Iron Galactic Element Recorder (SuperTIGER) balloon experiment, was evaluated in a CERN test beam (H8A) during Nov - Dec 2018. The 500 μm thick, single-sided silicon detectors have 32 DC-coupled strips with 3 mm pitch on the junction side with 9.6×9.6 cm^2 active area. Discrete charge-preamplifiers and shaping amplifiers were used to read out the ohmic and junction side signals simultaneously using the SuperTIGER DAQ system. We report on the response in a configuration where all 32 strips were joined and read out together. The strip detector-under-test was situated between planar silicon detectors, which provided the charge selection as well as a comparison of the measured response of each detector. The combined data set shows excellent charge resolution and finely resolved elemental peaks from helium (Z=2) through lead (Z=82). In this paper, we provide a description of the test beam experiment and the results of the charge resolution analysis

    Capacity for LDL (Low-Density Lipoprotein) Retention Predicts the Course of Atherogenesis in the Murine Aortic Arch.

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    BACKGROUND To cause atherosclerosis, LDLs (low-density lipoproteins) must first pass through the endothelium and then become retained in the arterial matrix. Which of these two processes is rate-limiting and predicts the topography of plaque formation remains controversial. To investigate this issue, we performed high-resolution mapping of LDL entry and retention in murine aortic arches before and during atherosclerosis development. METHODS Maps of LDL entry and retention were created by injecting fluorescently labeled LDL followed by near-infrared scanning and whole-mount confocal microscopy after 1 hour (entry) and 18 hours (retention). By comparing arches between normal mice and mice with short-term hypercholesterolemia, we analyzed changes in LDL entry and retention during the LDL accumulation phase that precedes plaque formation. Experiments were designed to secure equal plasma clearance of labeled LDL in both conditions. RESULTS We found that LDL retention is the overall limiting factor for LDL accumulation but that the capacity for LDL retention varied substantially over surprisingly short distances. The inner curvature region, previously considered a homogenous atherosclerosis-prone region, consisted of dorsal and ventral zones with high capacity and a central zone with low capacity for continued LDL retention. These features predicted the temporal pattern of atherosclerosis, which first appeared in the border zones and later in the central zone. The limit to LDL retention in the central zone was intrinsic to the arterial wall, possibly caused by saturation of the binding mechanism, and was lost upon conversion to atherosclerotic lesions. CONCLUSIONS Capacity for continued LDL retention varies over short distances and predicts where and when atherosclerosis develops in the mouse aortic arch.This study was supported by grants from the Ministerio de Economía, Industria y Competitividad (MEIC) with cofunding from the European Regional Development Fund (SAF2016-75580-R and PID2019-108568RB-I00), the Novo Nordisk Foundation (NNF17OC0030688) and the La Caixa Health Research Programme (HR20-00075, AtheroConvergence). V. Labrador-Cantarero is supported by FEDER “Una manera de hacer Europa” for the project In Vivo Advanced Nanoscopy at the ICTS–ReDib–TRIMA–CNIC. CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia e Innovación, and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015-0505).S

    La disfunción familiar como predisponente de la enfermedad mental. ¿Existe tal asociación?

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    ObjetivosEl objetivo principal es conocer la relación entre la disfunción familiar y la presencia de trastorno mental. El objetivo secundario es conocer la prevalencia y la distribución de los principales tipos de patología mental en la población atendida en atención primaria.Diseño y emplazamientoEstudio descriptivo y transversal realizado en 6 consultas de medicina de familia de un área básica de salud semiurbana.MétodoSe seleccionaron 280 sujetos mediante muestreo aleatorio sistemático de los que acudieron espontáneamente a la consulta. Mediante entrevista se recogieron las variables de estudio: dinámica familiar (medida mediante el test de APGAR familiar), estructura familiar, variables sociodemográficas y presencia de trastorno mental detectado mediante la Mini International Neuropsyquiatric Interview (MINI-DSM IV).ResultadosAceptaron participar 264 sujetos. Un 64,4% era mujer y la media de edad fue de 45,6 años (DE, 16,7). Se detectó patología mental en 87 participantes (33%), siendo la patología más frecuente trastorno de ansiedad generalizada, distimia y depresión mayor. Se encontró alteración de la dinámica familiar en 32 personas (12,3%). No se observaron diferencias significativas en la frecuencia de presentación de patología mental entre el grupo con disfunción familiar y el resto.ConclusionesLos trastornos de salud mental son frecuentes entre los pacientes que acuden a las consultas de atención primaria. No encontramos asociación entre las alteraciones de la dinámica familiar y los trastornos de salud mental, lo que podría deberse a la dificultad para detectar disfunción familiar con el test de APGAR.ObjectivesThe main purpose is to describe the relationship between family disfunction and mental disorder. The secondary objective is to know the prevalence and distribution of mental disorders in primary care attended population.DesignA cross-sectional study was conducted in a primary care setting.Patients and methodsRandom sample was selected over 280 subjects from consultant population. The variables (family function, family structure, social and economic conditions and mental disorders) were collected through interview. APGAR test and Mini International Neuropsychiatric Interview test were performed.Results264 patients were finally included (64% women). Mean age was 45,6 years (SD 16,7). Mental disorders were detected in 87 patients (33%). The most prevalent disorders were generalized anxiety disorder, dysthymia and major depression. family disfunction was found in 32 patients (12,3%). Prevalence of mental disorders wasn't statistically different in the group with family disfunction.ConclusionMental disorders are a common problem between primary care attended population. There wasn't any association between family disfunction and mental disorders, because of the limitations in the APGAR test in detecting family disfunction

    A measurement of cosmic ray deuterium from 0.5–2.9 GeV/nucleon

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    The rare isotopes ^(2)H and ^(3)He in cosmic rays are believed to originate mainly from the interaction of high energy protons and helium with the galactic interstellar medium. The unique propagation history of these rare isotopes provides important constraints on galactic cosmic ray source spectra and on models for their propagation within the Galaxy. Hydrogen and helium isotopes were measured with the balloon-borne experiment, IMAX, which flew from Lynn Lake, Manitoba in 1992. The energy spectrum of deuterium between 0.5 and 3.2 GeV/nucleon measured by the IMAX experiment as well as previously published results of ^(3)He from the same instrument will be compared with predictions of cosmic ray galactic propagation models. The observed composition of the light isotopes is found to be generally consistent with the predictions of the standard Leaky Box Model derived to fit observations of heavier nucle

    Observations and Interpretations of Energetic Neutral Hydrogen Atoms from the December 5, 2006 Solar Event

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    We discuss recently reported observations of energetic neutral hydrogen atoms (ENAs) from an X9 solar flare/coronal mass ejection event on 5 December 2006, located at E79. The observations were made by the Low Energy Telescopes (LETs) on STEREO A and B. Prior to the arrival of the main solar energetic particle (SEP) event at Earth, both LETs observed a sudden burst of 1.6 to 15 MeV energetic neutral hydrogen atoms produced by either flare or shock-accelerated protons. RHESSI measurements of the 2.2-MeV gamma-ray line provide an estimate of the number of interacting flare-accelerated protons in this event, which leads to an improved estimate of ENA production by flare-accelerated protons. Taking into account ENA losses, we find that the observed ENAs must have been produced in the high corona at heliocentric distances > or equal to 2 solar radii. Although there are no CME images from this event, it is shown that CME-shock-accelerated protons can, in principle, produce a time-history consistent with the observations

    SuperTIGER-2 2018 Flight Payload Recovery and Preliminary Instrument Assessment

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    The SuperTIGER (Trans-Iron Galactic Element Recorder) experiment was launched for the second time from the Long Duration Balloon (LDB) site near McMurdo Station, Antarctica on December 20, 2018 at 1:36 AM NZDT. The balloon reached a peak altitude of ∼79,300 ft before it began to descend, and the flight had to be terminated after just over six hours aloft. The payload landed at 8:17 AM NZDT approximately 150 miles from McMurdo Station at 75.80 S and 161.68 E. Satellite imagery of the site revealed that it was in a crevasse field, but a Twin Otter reconnaissance flight showed none in the immediate vicinity. A subsequent site survey by a team flown in by helicopter with ground penetrating radar was able to flag a safe zone including helicopter landing sites. The SuperTIGER-2 payload was recovered in two days with two Bell 212 helicopters followed by one day with a Basler, which involved transferring the payload to a safe fixed wing landing site roughly two miles away in three helicopter sling loads. After return to the LDB site the instrument modules were reassembled, rewired and tested prior to their being shipped north. The instrument was found to be in overall good condition, with all testable electronics channels working, and minimal mechanical damage. SuperTIGER-2 could be refurbished to fly again as early as this next Antarctic season
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