Scaling laws of quiet-Sun coronal loops

We study a series of relations between physical parameters in coronal loops of the quiet Sun reconstructed by combining tomographic techniques and modeling of the coronal magnetic field. We use differential emission measure tomography (DEMT) to determine the three-dimensional distribution of the electron density and temperature in the corona, and we model the magnetic field with a potential-field source-surface (PFSS) extrapolation of a synoptic magnetogram. By tracing the DEMT products along the extrapolated magnetic field lines, we obtain loop-averaged electron density and temperature. Also, loop-integrated energy-related quantities are computed for each closed magnetic field line. We apply the procedure to Carrington rotation 2082, during the activity minimum between Solar Cycles 23 and 24, using data from the Extreme Ultraviolet Imager on board the Solar Terrestrial Relations Observatory (STEREO) spacecraft. We find a scaling law between the loop-average density N and loop length L,Nm∼L-0.35, but we do not find a significant relation between loop-average temperature and loop length. We confirm though the previously found result that loop-average temperatures at the equatorial latitudes are lower than at higher latitudes. We associate this behavior with the presence at the equatorial latitudes of loops with decreasing temperatures along their length (“down” loops), which are in general colder than loops with increasing temperatures (“up” loops). We also discuss the role of “down” loops in the obtained scaling laws of heating flux versus loop length for different heliographic latitudes. We find that the obtained scalings for quiet-Sun loops do not generally agree with those found in the case of AR loops from previous observational and theoretical studies. We suggest that to better understand the relations found, it is necessary to forward model the reconstructed loops using hydrodynamic codes working under the physical conditions of the quiet-Sun corona.Fil: Mac Cormack, Cecilia. Universidad Nacional de Tres de Febrero; Argentina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Lopez Fuentes, Marcelo Claudio. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Mandrini, Cristina Hemilse. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Lloveras, Diego Gustavo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Poisson, Mariano. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina. Universidad Nacional de Tres de Febrero; ArgentinaFil: Vasquez, Alberto Marcos. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina. Universidad Nacional de Tres de Febrero; Argentin

Targeting of arenavirus RNA synthesis by a carboxamide-derivatized aromatic disulfide with virucidal activity.

Several arenaviruses can cause severe hemorrhagic fever (HF) in humans, representing a public health threat in endemic areas of Africa and South America. The present study characterizes the potent virucidal activity of the carboxamide-derivatized aromatic disulfide NSC4492, an antiretroviral zinc finger-reactive compound, against Junín virus (JUNV), the causative agent of Argentine HF. The compound was able to inactivate JUNV in a time and temperature-dependent manner, producing more than 99 % reduction in virus titer upon incubation with virions at 37 °C for 90 min. The ability of NSC4492-treated JUNV to go through different steps of the multiplication cycle was then evaluated. Inactivated virions were able to bind and enter into the host cell with similar efficiency as control infectious particles. In contrast, treatment with NSC4492 impaired the capacity of JUNV to drive viral RNA synthesis, as measured by quantitative RT-PCR, and blocked viral protein expression, as determined by indirect immunofluorescence. These results suggest that the disulfide NSC4492 targets on the arenavirus replication complex leading to impairment in viral RNA synthesis. Additionally, analysis of VLP produced in NSC4492-treated cells expressing JUNV matrix Z protein revealed that the compound may interact with Z resulting in an altered aggregation behavior of this protein, but without affecting its intrinsic self-budding properties. The potential perspectives of NSC4492 as an inactivating vaccinal compound for pathogenic arenaviruses are discussed.Fil: Sepúlveda, Claudia Soledad. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Quimica Biologica;Fil: Garcia, Cybele. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Quimica Biologica;Fil: Levingston Mac Leod, Jesica Mariana. Consejo Nacional de Invest.cientif.y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Cs. y Tecnologia "dr. Cesar Milstein";Fil: Lopez, Nora Mabel. Consejo Nacional de Invest.cientif.y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Cs. y Tecnologia "dr. Cesar Milstein";Fil: Damonte, Elsa Beatriz. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Quimica Biologica

Three-Dimensional Reconstruction and Thermal Modeling of Observed Loops

Due to their characteristic temperature and density, loop structures in active regions (ARs) can be seen bright in extreme ultraviolet (EUV) and soft X-ray images. The semiempirical determination of the three-dimensional (3D) distribution of basic physical parameters (electronic density and temperature, and magnetic field) is a key constraint for coronal heating models. In this work we develop a technique for the study of EUV bright loops based on differential emission measure (DEM) analysis and we first apply it to AR structures observed by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). The 3D structure and intensity of the magnetic field of the observed EUV loops are modeled using force-free field extrapolations based on magnetograms taken by the Helioseismic and Magnetic Imager (HMI) on board SDO. In this work we report the results obtained for several bright loops identified in different ARs. Our analysis indicates that the mean and width of the temperature distributions are nearly invariant along the loop lengths. For a particular loop we study its temporal evolution and find that these characteristics remain approximately constant for most of its life time. The appearance and disappearance of this loop occurs at time-scales much shorter than its life time of ≈ 2.5 hours. The results of this analysis are compared with numerical simulations using the zero-dimensional (0D) hydrodynamic model, Enthalpy-Based Thermal Evolution of Loops (EBTEL). We study two alternative heating scenarios: first, we apply a constant heating rate assuming loops in quasi-static equilibrium, and second, we heat the loops using impulsive events or nanoflares. We find that all the observed loops are overdense with respect to a quasi-static equilibrium solution and that the nanoflare heating better reproduces the observed densities and temperatures.Fil: Nuevo, Federico Alberto. Universidad de Buenos Aires. Ciclo Básico Común; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Mac Cormack, Cecilia. Universidad Nacional de Tres de Febrero. Departamento de Ciencia y Tecnologia.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Lopez Fuentes, Marcelo Claudio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Vasquez, Alberto Marcos. Universidad Nacional de Tres de Febrero. Departamento de Ciencia y Tecnologia.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Mandrini, Cristina Hemilse. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentin

Gestión administrativa en las Municipalidades de Mazamari, San Martín de Pangoa y Río Negro de la Provincia de Satipo, 2021

En 2021 se realizó un estudio titulado Gestión Administrativa en las Municipalidades Mazamari, San Martín de Pangoa y Río Negro de la provincia de Satipo, 2021”. El objetivo fue identificar la diferencia que existe en las gestiones administrativas de los municipios de Mazamari, San Martín de Pangoa y Río Negro de la provincia de Satipo, 2021. El método utilizado en la presente investigación fue el científico y en lo especifico se empleó el método hipotético deductivo siendo el tipo de investigación básica de nivel descriptivo, así también su diseño utilizado fue el descriptivo comparativo cuyo tamaño de población fue de 384 personas y como muestra se seleccionó a 90 usuarios que comprende a las municipalidades de Mazamari, San Martín de Pangoa y Satipo. Los usuarios de las Municipalidades de Mazamari, San Martín de Pangoa y Río Negro respondieron en un 28%, 16% y 18% respectivamente la primera variable de nombre gestión administrativa dando así un acierto a la hipótesis que existe ciertas diferencias de significativas en la gestión administrativa entre las municipalidades de Mazamari, San Martín de Pangoa y Río Negro de la provincia de Satipo, 2021. De acuerdo con los resultados, se llega a la conclusión de que hay notables diferencias en la forma en que se lleva a cabo la gestión administrativa entre las municipalidades de Mazamari, San Martín de Pangoa y Río Negro de la provincia de Satipo, 2021. Además, se recomienda a la municipalidad de Mazamari seguir trabajando en la mejora ya que siempre se encuentra en algo que mejorar, en caso de las municipalidades de San Martín de Pango y Río Negro para su mejora deberán tomar como referencia la gestión de la municipalidad de Mazamari

Radial imbibition in paper under temperature differences

Spontaneous radial imbibition into thin circular samples of porous material when they have been subjected to radial temperature differences was analyzed theoretically and experimentally. The use of the Darcy equation allows us to take into account temperature variations in the dynamic viscosity and surface tension in order to found the one-dimensional equation for the imbibition fronts. Experiments in blotting paper show the good fit between the experimental data to theoretical profiles.Fil: Lopez Villa, Abel. Instituto Politécnico Nacional. Centro de Investigación y de Estudios Avanzados. Departamento de Investigaciones Educativas.; MéxicoFil: Medina, Abraham. Instituto Politécnico Nacional. Centro de Investigación y de Estudios Avanzados. Departamento de Investigaciones Educativas.; MéxicoFil: Higuera, F. J.. No especifíca;Fil: Mac Intyre, Jonatan Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Física Arroyo Seco; ArgentinaFil: Perazzo, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; ArgentinaFil: Gomba, Juan Manuel. Universidad Favaloro; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Tandil. Centro de Investigaciones En Fisica E Ingenieria del Centro de la Provincia de Buenos Aires. Sede Olavarria del Centro de Investifaciones En Fisica E Ingenieria del Centro de la Provincia de Buenos Aires | Universidad Nacional del Centro de la Pcia.de Bs.as.. Centro de Investigaciones En Fisica E Ingenieria del Centro de la Provincia de Buenos Aires. Sede Olavarria del Centro de Investifaciones En Fisica E Ingenieria del Centro de la Provincia de Buenos Aires.; Argentin

Caracterización clínico-patológica, genotipificación viral y heterogeneidad genética como determinantes de riesgo en COVID-19: Diseño del estudio y hallazgos iniciales: Clinical-pathological characterization, viral genotipification and genetic heterogeneity as risk determinants in COVID-19: Study design and initial findings

Introduction: The objective of the study is to describe the clinical, pathological, virological and genetic characteristics ofthe immune response of patients diagnosed with SARS-CoV-2 infection and its relationship with the unfavorable courseof the disease. Methods: Descriptive, relational, longitudinal and retrospective study based on the review of medicalrecords, taking post-mortem tru-cut biopsies of the lung and liver, taking blood samples and naso-oropharyngeal swabor endotracheal tube aspirate. In the first phase, the biopsies will be processed and studied with conventional andimmunohistochemical histology in the Pathological Anatomy service of the Carlos Seguín Escobedo National Hospitalin Arequipa, Peru. Results: Advanced mean age, male sex, and the presence of comorbidities were predominant indeceased patients. Lung biopsies showed predominantly the exudative and partially proliferative phases of diffuseand focal alveolar damage, associated primarily with intraalveolar macrophage hyperplasia with accumulation withinthe alveolar space-resembling desquamative pneumonia, as well as atypical binucleated intraalveolar pneumocytes,with eosinophilic nucleoli (similar to virocytes) in some cases. In the vast majority of cases, intravascular fibrin depositsassociated with the accumulation of inflammatory cells composed of neutrophils and monocytes, representingmicrothrombosis, were observed. Liver biopsies showed predominantly macrovesicular steatosis and in twocases microvesicular steatosis was observed. Additionally, varying degrees of necrosis and mild portal and lobularinflammation were observed. Conclusion: The clinical and pathological findings in this first report are consistent withprevious publications and confirm the pattern of diffuse alveolar damage associated with aggregates of intraalveolarmacrophages and microthrombosis; confirms in addition, macro and microvesicular hepatocytic steatosis, togetherwith variable degrees of necrosis.Introducción: El objetivo del estudio es describir las características clínicas, patológicas, virológicas y genéticas de larespuesta inmune de los pacientes diagnosticados con infección por SARS-CoV-2 y su relación con el curso desfavorablede la enfermedad. Métodos: Estudio descriptivo, relacional, longitudinal y retrospectivo basado en la revisión dehistorias clínicas, toma de biopsias tru-cut post-mortem de pulmón e hígado, toma de muestras de sangre e hisopadonaso-orofaríngeo o de aspirado del tubo endotraqueal. En la primera fase las biopsias serán procesadas y estudiadascon histología convencional e inmunohistoquímica en el servicio de Anatomía Patológica del hospital NacionalCarlos Seguín Escobedo de Arequipa, Perú. Resultados: La edad media avanzada, el sexo masculino y la presencia decomorbilidades fue predominante en los pacientes fallecidos. Las biopsias pulmonares mostraron predominantementelas fases exudativa y parcialmente proliferativa del daño alveolar difuso y focal, asociada principalmente a unahiperplasia de macrófagos intraalveolares con acumulación dentro del espacio alveolar, semejando una neumoníadescamativa, así como neumocitos intraalveolares binucleados y atípicos, con nucléolos eosinofílicos (semejante avirocitos) en algunos casos. En la gran mayoría de casos se observaron depósitos de fibrina intravascular asociadaal acúmulo de células inflamatorias compuestas por neutrófilos y monocitos, representando microtrombosis. Lasbiopsias de hígado mostraron esteatosis predominantemente macrovesicular y en dos casos se observó esteatosismicrovesicular. Adicionalmente, se observaron diversos grados de necrosis e inflamación portal y lobular. Conclusión:Los hallazgos clínicos y patológicos en este primer reporte son consistentes con publicaciones previas y confirmanel patrón de daño alveolar difuso asociado a agregados de macrofagos intraalveolares y microtrombosis; ademasesteatosis macro y microvesicular hepatocitica, junto a grados variables de necrosis

Effects of lean interventions supported by digital technologies on healthcare services: a systematic review

Despite the increasing utilization of lean practices and digital technologies (DTs) related to Industry 4.0, the impact of such dual interventions on healthcare services remains unclear. This study aims to assess the effects of those interventions and provide a comprehensive understanding of their dynamics in healthcare settings. The methodology comprised a systematic review following the PRISMA guidelines, searching for lean interventions supported by DTs. Previous studies reporting outcomes related to patient health, patient flow, quality of care, and efficiency were included. Results show that most of the improvement interventions relied on lean methodology followed by lean combined with Six Sigma. The main supporting technologies were simulation and automation, while emergency departments and laboratories were the main settings. Most interventions focus on patient flow outcomes, reporting positive effects on outcomes related to access to service and utilization of services, including reductions in turnaround time, length of stay, waiting time, and turnover time. Notably, we found scarce outcomes regarding patient health, staff wellbeing, resource use, and savings. This paper, the first to investigate the dual intervention of DTs with lean or lean−Six Sigma in healthcare, summarizes the technical and organizational challenges associated with similar interventions, encourages further research, and promotes practical applications

The Nature and Origin of Low-Redshift O VI Absorbers

The O VI ion observed in quasar absorption line spectra is the most accessible tracer of the cosmic metal distribution in the low redshift (z<0.5) intergalactic medium (IGM). We explore the nature and origin of O VI absorbers using cosmological hydrodynamic simulations including galactic outflows. We consider the effects of ionization background variations, non-equilibrium ionization and cooling, uniform metallicity, and small-scale (sub-resolution) turbulence. Our main results are 1) IGM O VI is predominantly photo-ionized with T= 10^(4.2+/-0.2) K. A key reason for this is that O VI absorbers preferentially trace over-enriched regions of the IGM at a given density, which enhances metal-line cooling such that absorbers can cool within a Hubble time. As such, O VI is not a good tracer of the WHIM. 2) The predicted O VI properties fit observables only if sub-resolution turbulence is added. The required turbulence increases with O VI absorber strength such that stronger absorbers arise from more recent outflows with turbulence dissipating on the order of a Hubble time. The amount of turbulence is consistent with other examples of turbulence observed in the IGM and galactic halos. 3) Metals traced by O VI and H I do not trace exactly the same baryons, but reside in the same large-scale structure. Observed alignment statistics are reproduced in our simulations. 4) Photo-ionized O VI traces gas in a variety of environments, and is not directly associated with the nearest galaxy, though is typically nearest to ~0.1L* galaxies. Weaker O VI components trace some of the oldest cosmic metals. 5) Very strong absorbers are more likely to be collisionally ionized, tracing more recent enrichment (<2 Gyr) within or near galactic halos.Comment: 33 pages, 18 figures, accepted to MNRAS. Two new figures adde

C IV absorption in damped and sub-damped Lyman-alpha systems: correlations with metallicity and implications for galactic winds at z~2-3

We present a study of C IV absorption in a sample of 63 damped Lyman-alpha (DLA) systems and 11 sub-DLAs in the redshift range 1.75<z_abs<3.61, using a dataset of high-resolution (6.6 km/s FWHM), high signal-to-noise VLT/UVES spectra. Narrow and broad C IV absorption line components indicate the presence of both warm, photoionized and hot, collisionally ionized gas. We report new correlations between the metallicity (measured in the neutral-phase) and each of the C IV column density, the C IV total line width, and the maximum C IV velocity. We explore the effect on these correlations of the sub-DLAs, the proximate DLAs (defined as those within 5 000 km/s of the quasar), the saturated absorbers, and the metal line used to measure the metallicity, and we find the correlations to be robust. There is no evidence for any difference between the measured properties of DLA C IV and sub-DLA C IV. In 25 DLAs and 4 sub-DLAs, covering 2.5 dex in [Z/H], we directly observe C IV moving above the escape speed, where v_esc is derived from the total line width of the neutral gas profiles. These high-velocity C IV clouds, unbound from the central potential well, can be interpreted as highly ionized outflowing winds, which are predicted by numerical simulations of galaxy feedback. The distribution of C IV column density in DLAs and sub-DLAs is similar to the distribution in Lyman Break galaxies, where winds are directly observed, supporting the idea that supernova feedback creates the ionized gas in DLAs. The unbound C IV absorbers show a median mass flow rate of ~22(r/40 kpc) solar masses per year, where r is the characteristic C IV radius. Their kinetic energy fluxes are large enough that a star formation rate (SFR) of ~2 solar masses per year is required to power them.Comment: 21 pages, accepted to A&A, Fig 1 downgraded, v2 with proof corrections made and improved Fig 1

Before the first supernova: combined effects of H II regions and winds on molecular clouds

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. © 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.We model the combined effects of photoionization and momentum-driven winds from O-stars on molecular clouds spanning a parameter space of initial conditions. The dynamical effects of the winds are very modest. However, in the lower mass clouds, they influence the morphologies of the H II regions by creating 10-pc-scale central cavities. The inhomogeneous structures of the model giant molecular clouds (GMCs) make them highly permeable to photons, ionized gas and supernova ejecta, and the leaking of ionized gas in particular strongly affects their evolution, reducing the effectiveness of feedback. Nevertheless, feedback is able to expel large fractions of the mass of the lower escape velocity clouds. Its impact on star formation is more modest, decreasing final star formation efficiencies by 10–20 per cent, and the rate of change of the star formation efficiency per freefall time by about one third. However, the clouds still form stars substantially faster than observed GMCs.Peer reviewe