Thru-reflect-line calibration for substrate integrated waveguide devices with tapered microstrip transitions

One of the main problems when exciting or measuring substrate integrated waveguide (SIW) devices lies in the need of a good interconnection with planar structures. In this reported work, the negative effects produced by the connectors and the tapered microstrip-to-SIW transitions are de-embedded from the measurements of the SIW structure by a thru-reflect-line calibration with an adequate and cheap SIW calibration kit.Díaz Caballero, E.; Belenguer Martínez, Á.; Esteban González, H.; Boria Esbert, VE. (2013). Thru-reflect-line calibration for substrate integrated waveguide devices with tapered microstrip transitions. Electronics Letters. 49(2):132-133. doi:10.1049/el.2012.3027S132133492Deslandes, D., & Wu, K. (2001). Integrated microstrip and rectangular waveguide in planar form. IEEE Microwave and Wireless Components Letters, 11(2), 68-70. doi:10.1109/7260.914305Henry, M., Free, C. E., Izqueirdo, B. S., Batchelor, J., & Young, P. (2009). Millimeter Wave Substrate Integrated Waveguide Antennas: Design and Fabrication Analysis. IEEE Transactions on Advanced Packaging, 32(1), 93-100. doi:10.1109/tadvp.2008.2011284Chen, X.-P., Wu, K., & Li, Z.-L. (2007). Dual-Band and Triple-Band Substrate Integrated Waveguide Filters With Chebyshev and Quasi-Elliptic Responses. IEEE Transactions on Microwave Theory and Techniques, 55(12), 2569-2578. doi:10.1109/tmtt.2007.909603Deslandes, D., & Ke Wu. (2005). Analysis and design of current probe transition from grounded coplanar to substrate integrated rectangular waveguides. IEEE Transactions on Microwave Theory and Techniques, 53(8), 2487-2494. doi:10.1109/tmtt.2005.852778Engen, G. F., & Hoer, C. A. (1979). Thru-Reflect-Line: An Improved Technique for Calibrating the Dual Six-Port Automatic Network Analyzer. IEEE Transactions on Microwave Theory and Techniques, 27(12), 987-993. doi:10.1109/tmtt.1979.1129778Chih-Jung Chen, & Tah-Hsiung Chu. (2009). Measurement of Noncoaxial Multiport Devices Up to the Intrinsic Ports. IEEE Transactions on Microwave Theory and Techniques, 57(5), 1230-1236. doi:10.1109/tmtt.2009.201735

Rhesus TRIM5α disrupts the HIV-1 capsid at the inter-hexamer interfaces

TRIM proteins play important roles in the innate immune defense against retroviral infection, including human immunodeficiency virus type-1 (HIV-1). Rhesus macaque TRIM5α (TRIM5αrh) targets the HIV-1 capsid and blocks infection at an early post-entry stage, prior to reverse transcription. Studies have shown that binding of TRIM5α to the assembled capsid is essential for restriction and requires the coiled-coil and B30.2/SPRY domains, but the molecular mechanism of restriction is not fully understood. In this study, we investigated, by cryoEM combined with mutagenesis and chemical cross-linking, the direct interactions between HIV-1 capsid protein (CA) assemblies and purified TRIM5αrh containing coiled-coil and SPRY domains (CC-SPRYrh). Concentration-dependent binding of CC-SPRYrh to CA assemblies was observed, while under equivalent conditions the human protein did not bind. Importantly, CC-SPRYrh, but not its human counterpart, disrupted CA tubes in a non-random fashion, releasing fragments of protofilaments consisting of CA hexamers without dissociation into monomers. Furthermore, such structural destruction was prevented by inter-hexamer crosslinking using P207C/T216C mutant CA with disulfide bonds at the CTD-CTD trimer interface of capsid assemblies, but not by intra-hexamer crosslinking via A14C/E45C at the NTD-NTD interface. The same disruption effect by TRIM5αrh on the inter-hexamer interfaces also occurred with purified intact HIV-1 cores. These results provide insights concerning how TRIM5α disrupts the virion core and demonstrate that structural damage of the viral capsid by TRIM5α is likely one of the important components of the mechanism of TRIM5α-mediated HIV-1 restriction. © 2011 Zhao et al

The Sensitivity of HAWC to High-Mass Dark Matter Annihilations

The High Altitude Water Cherenkov (HAWC) observatory is a wide field-of-view detector sensitive to gamma rays of 100 GeV to a few hundred TeV. Located in central Mexico at 19 degrees North latitude and 4100 m above sea level, HAWC will observe gamma rays and cosmic rays with an array of water Cherenkov detectors. The full HAWC array is scheduled to be operational in Spring 2015. In this paper, we study the HAWC sensitivity to the gamma-ray signatures of high-mass (multi- TeV) dark matter annihilation. The HAWC observatory will be sensitive to diverse searches for dark matter annihilation, including annihilation from extended dark matter sources, the diffuse gamma-ray emission from dark matter annihilation, and gamma-ray emission from non-luminous dark matter subhalos. Here we consider the HAWC sensitivity to a subset of these sources, including dwarf galaxies, the M31 galaxy, the Virgo cluster, and the Galactic center. We simulate the HAWC response to gamma rays from these sources in several well-motivated dark matter annihilation channels. If no gamma-ray excess is observed, we show the limits HAWC can place on the dark matter cross-section from these sources. In particular, in the case of dark matter annihilation into gauge bosons, HAWC will be able to detect a narrow range of dark matter masses to cross-sections below thermal. HAWC should also be sensitive to non-thermal cross-sections for masses up to nearly 1000 TeV. The constraints placed by HAWC on the dark matter cross-section from known sources should be competitive with current limits in the mass range where HAWC has similar sensitivity. HAWC can additionally explore higher dark matter masses than are currently constrained.Comment: 15 pages, 4 figures, version to be published in PR

Cirugía mínimamente invasiva de la hernia inguinal

El abordaje mínimamente invasivo de la hernia inguinal presenta ventajas respecto a los abordajes convencionales anteriores en las hernias inguinales bilaterales y recurrentes, si bien los resultados iniciales fueron malos, se sumaron nuevos problemas derivados del abordaje laparoscópico. El objetivo de este artículo es describir la técnica quirúrgica y analizar los resultados preliminares de nuestra serie de 600 hernioplastias totalmente extraperitoneales realizadas en la Clínica Universitaria de Navarra. La complicación intraoperatoria más frecuente (25,7%) fue la apertura accidental del peritoneo. No hubo complicaciones intrabdominales asociadas. En el seguimiento hubo 9 (1,5%) recidivas y 13 reintervenciones. Once (1,8%) pacientes desarrollaron dolor neuropático transitorio en el territorio del fémoro-cutáneo. En nuestra experiencia el abordaje totalmente extraperitoneal es una técnica especialmente indicada en hernias recidivadas y bilaterales. Las ventajas presentes en cuanto a dolor y disconfort postoperatorio, recuperación de la actividad física y laboral, y los buenos resultados en cuanto a recidivas y dolor neuropático nos animan a indicarla no sólo en las hernias inguinales recidivadas o bilaterales sino en las primarias

Calidad de vida y estrés en estudiantes de medicina en Cajamarca-Perú-2023

Objectives: Determine the influence of quality of life on the stress of medical students at a university in Cajamarca during 2023. Identify the level of quality of life and the degree of stress, and establish the dimensions of quality of life and others. factors that influence stress. Materials and methods: The present study was basic with a quantitative approach, cross-sectional with a correlational method. The student population was 175 students, and the sample was 106 students. The SISCO SV-21 questionnaire with Cronbach's alpha of 0.85 and the WHOQOL-BREF 26 questionnaire with Cronbach's alpha of 0.89 were used. For the treatment of the collected information, descriptive and inferential statistics were used with a level of significance p<0.05 using the Excel statistical package and the Epi Info system. Results: We found 71.70% high levels of stress and 96 % of a low quality of life. A value of p = 0.317 was found with respect to the relationship of the two variables. Regarding the dimensions of the quality of life that predisposes to have high stress, it was found significant to psychological health (p = 0.0025) and PR of 2.88; and social relationships (p= 0.036). Finally, in relation to gender and presentation of stress (significant p of =0.0084) with PR of 1.37. Conclusion: There is no significant correlation between stress and the quality of life of medical students. There are high levels of stress and a feeling of poor quality of life among students. The female sex, mental health and social relationships are significantly related to high levels of stress.Objetivos: Determinar la influencia de la calidad de vida en el estrés de los estudiantes de medicina de una universidad de Cajamarca durante el 2023. Identificar el nivel de calidad de vida y el grado de estrés, y establecer las dimensiones de calidad de vida y otros factores que influyen en el estrés. Materiales y métodos: El presente estudio fue tipo básico con enfoque cuantitativo, de tipo transversal con método correlacional. La población de estudiantes fue de 175 estudiantes, y la muestra fue de 106 estudiantes. Se usó el cuestionario SISCO SV-21 con alfa de Cronbach del 0.85 y el cuestionario WHOQOL-BREF 26 con alfa de Cronbach del 0.89. Para el tratamiento de la información recolectada, se usó la estadística descriptiva e inferencial con un nivel de significancia p<0.05 usando para ello el paquete estadístico Excel y el sistema Epi Info. Resultados: Encontramos un 71,70% altos niveles de estrés y 96% de una calidad de vida baja. Se halló un valor de p = 0.317 con respecto a la relación de las dos variables. Con respecto a las dimensiones de la calidad de vida que predispone a tener estrés alto, se encontró significativo a la salud psicológica (p = 0.0025) y RP de 2.88; y las relaciones sociales (p= 0.036). Finalmente, en relación a sexo y presentación de estrés (p significativo de =0,0084) con RP de 1.37. Conclusión: No existe correlación significativa entre el estrés y la calidad de vida de los estudiantes de medicina, Existen elevados niveles de estrés y de sensación de mala calidad de vida entre los estudiantes. El sexo femenino, la salud mental y las relaciones sociales se relacionan significativamente con elevados de estrés

The Mass-Metallicity relation explored with CALIFA: I. Is there a dependence on the star formation rate?

We present the results on the study of the global and local M-Z relation based on the first data available from the CALIFA survey (150 galaxies). This survey provides integral field spectroscopy of the complete optical extent of each galaxy (up to 2-3 effective radii), with enough resolution to separate individual HII regions and/or aggregations. Nearly $\sim$3000 individual HII regions have been detected. The spectra cover the wavelength range between [OII]3727 and [SII]6731, with a sufficient signal-to-noise to derive the oxygen abundance and star-formation rate associated with each region. In addition, we have computed the integrated and spatially resolved stellar masses (and surface densities), based on SDSS photometric data. We explore the relations between the stellar mass, oxygen abundance and star-formation rate using this dataset. We derive a tight relation between the integrated stellar mass and the gas-phase abundance, with a dispersion smaller than the one already reported in the literature ($\sigma_{\Delta{\rm log(O/H)}}=$0.07 dex). Indeed, this dispersion is only slightly larger than the typical error derived for our oxygen abundances. However, we do not find any secondary relation with the star-formation rate, other than the one induced due to the primary relation of this quantity with the stellar mass. We confirm the result using the $\sim$3000 individual HII regions, for the corresponding local relations. Our results agree with the scenario in which gas recycling in galaxies, both locally and globally, is much faster than other typical timescales, like that of gas accretion by inflow and/or metal loss due to outflows. In essence, late-type/disk dominated galaxies seem to be in a quasi-steady situation, with a behavior similar to the one expected from an instantaneous recycling/closed-box model.Comment: 19 Pages, 8 figures, Accepted for Publishing in Astronomy and Astrophysics (A&A

Extreme Starbursts in the Local Universe

The "Extreme starbursts in the local universe" workshop was held at the Insituto de Astrofisica de Andalucia in Granada, Spain on 21-25 June 2010. Bearing in mind the advent of a new generation of facilities such as JWST, Herschel, ALMA, eVLA and eMerlin, the aim of the workshop was to bring together observers and theorists to review the latest results. The purpose of the workshop was to address the following issues: what are the main modes of triggering extreme starbursts in the local Universe? How efficiently are stars formed in extreme starbursts? What are the star formation histories of local starburst galaxies? How well do the theoretical simulations model the observations? What can we learn about starbursts in the distant Universe through studies of their local counterparts? How important is the role of extreme starbursts in the hierarchical assembly of galaxies? How are extreme starbursts related to the triggering of AGN in the nuclei of galaxies? Overall, 41 talks and 4 posters with their corresponding 10 minutes short talks were presented during the workshop. In addition, the workshop was designed with emphasis on discussions, and therefore, there were 6 discussion sessions of up to one hour during the workshop. Here is presented a summary of the purposes of the workshop as well as a compilation of the abstracts corresponding to each of the presentations. The summary and conclusions of the workshop along with a description of the future prospects by Sylvain Veilleux can be found in the last section of this document. A photo of the assistants is included.Comment: worksho

VAMOS: a Pathfinder for the HAWC Gamma-Ray Observatory

VAMOS was a prototype detector built in 2011 at an altitude of 4100m a.s.l. in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design, construction techniques and data acquisition system of the HAWC observatory. HAWC is an air-shower array currently under construction at the same site of VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water Cherenkov detectors and two different data acquisition systems. It was in operation between October 2011 and May 2012 with an average live time of 30%. Besides the scientific verification purposes, the eight months of data were used to obtain the results presented in this paper: the detector response to the Forbush decrease of March 2012, and the analysis of possible emission, at energies above 30 GeV, for long gamma-ray bursts GRB111016B and GRB120328B.Comment: Accepted for pubblication in Astroparticle Physics Journal (20 pages, 10 figures). Corresponding authors: A.Marinelli and D.Zaboro