The health from the humanist perspective of Blas Álvarez de Miraval

A pesar de que existen diferentes estudios en las Ciencias de la Actividad Física y del Deporte sobre autores humanistas, el objetivo del presente trabajo es poner en valor la obra de una de las figuras más importantes del humanismo español, Blas Álvarez de Miraval, insigne médico y teólogo, a través del análisis pormenorizado de su obra cumbre, titulada De la conservación de la salud del cuerpo y el alma, cuyos resultados arrojan una visión única y diferente de lo que ha de ser la conservación de la salud desde una perspectiva integral por parte del individuoIn spite of the fact that there are different studies in the Sciences of the Sport on humanist authors, the aim of the present work is to put of relevancy the work of one of the most important figures of the Spanish humanism, Blas Álvarez de Miraval, celebrated doctor and theologian, with regard to the Sciences of the Physical Activity and of the Sport by means of the study detailed of his greatest work, "Of the conservation of the health of the body and the soul", which results throw an only and different vision from what has to be the conservation of the health from the integral care of the individua

A model for high-mass microquasar jets under the influence of a strong stellar wind

Context. High-mass microquasars (HMMQs) are systems from which relativistic jets are launched. At the scales of several times the binary system size, the jets are expected to follow a helical path caused by the interaction with a strong stellar wind and orbital motion.Such a trajectory has its influence on the non-thermal emission of the jets, which also depends strongly on the observing angle due to Doppler boosting effects. Aims. We explore how the expected non-thermal emission of HMMQ jets at small scales is affected by the impact of the stellar wind and the orbital motion on the jet propagation. Methods. We studied the broadband non-thermal emission, from radio to gamma rays, produced in HMMQ jets up to a distance of several orbital separations, taking into account a realistic jet trajectory, different model parameters, and orbital modulation. The jet trajectory is computed by considering momentum transfer with the stellar wind. Electrons are injected at the position where a recollimation shock in the jets is expected due to the wind impact. Their distribution along the jet path is obtained assuming local acceleration at the recollimation shock, and cooling via adiabatic, synchrotron, and inverse Compton processes. The synchrotron and inverse Compton emission is calculated taking into account synchrotron self-absorption within the jet, free-free absorption with the stellar wind, and absorption by stellar photons via pair production. Results. The spectrum is totally dominated by the jet over the counter-jet due to Doppler boosting. Broadband emission from microwaves to gamma rays is predicted, with radio emission being totally absorbed. This emission is rather concentrated in the regions close to the binary system and features strong orbital modulation at high energies. Asymmetric light curves are obtained owing to the helical trajectory of the jets. Conclusions. The presence of helical shaped jets could be inferred from asymmetries in the light curves, which become noticeable only for large jet Lorentz factors and low magnetic fields. Model parameters could be constrained if accurate phase-resolved lightcurves from GeV to TeV energies were available. The predictions for the synchrotron and the inverse Compton radiation are quite sensitive of the parameters determining the wind-jet interaction structure

Gamma rays from jets interacting with BLR clouds in blazars

Context. The innermost parts of powerful jets in active galactic nuclei are surrounded by dense, high-velocity clouds from the broad-line region, which may penetrate into the jet and lead to the formation of a strong shock. Such jet-cloud interactions are expected to have measurable effects on the γ-ray emission from blazars. Aims. We characterise the dynamics of a typical cloud-jet interaction scenario, and the evolution of its radiative output in the 0.1-30 GeV energy range, to assess to what extent these interactions can contribute to the γ-ray emission in blazars. Methods. We use semi-analytical descriptions of the jet-cloud dynamics, taking into account the expansion of the cloud inside the jet and its acceleration. Assuming that electrons are accelerated in the interaction and making use of the hydrodynamical information, we then compute the high-energy radiation from the cloud, including the absorption of γ-rays in the ambient photon field through pair creation. Results. Jet-cloud interactions can lead to significant γ-ray fluxes in blazars with a broad-line region (BLR), in particular when the cloud expansion and acceleration inside the jet are taken into account. This is caused by 1) the increased shocked area in the jet, which leads to an increase in the energy budget for the non-thermal emission; 2) a more efficient inverse Compton cooling with the boosted photon field of the BLR; and 3) an increased observer luminosity due to Doppler boosting effects. Conclusions. For typical broad-line region parameters, either (i) jet-cloud interactions contribute significantly to the persistent γ-ray emission from blazars or (ii) the BLR is far from spherical or the fraction of energy deposited in non-thermal electrons is smal

Gamma-ray emission from interactions between jets and BLR clouds

Blazars -active galactic nuclei with a jet pointing towards the observer- are the most numerous γ-ray sources detected until date. In this work we show preliminary results of a model in which broad-line region (BLR) clouds penetrate in the jet, producing shocks capable of accelerating relativistic electrons; these electrons emit γ-rays when they interact with the photons coming from the BLR clouds. We calculate semi-analytically the dynamical evolution of a typical cloud inside the jet, the energy distribution of the locally accelerated electrons, and the high-energy emission the latter produce, taking into account relativistic effects. We estimate the dutycycle of these interactions in order to find whether they occur as discrete events or almost continuous. We compare the observed γ-ray fluxes with the ones predicted by our model and discuss the implications in terms of particle acceleration efficiency and mass-loading in the blazar jets

Non-thermal emission from star-forming galaxies detected in gamma rays

Star-forming galaxies (SFGs) emit non-thermal radiation from radio to gamma-rays. We aim to investigate the main mechanisms of global CR transport and cooling in SFGs. The way they contribute in shaping the relations between non-thermal luminosities and SFR could shed light onto their nature. We develop a model to compute the CR populations of SFGs, taking into account their production, transport, and cooling. The model is parameterised only through global galaxy properties, and describes the non-thermal emission in both radio and gamma-rays. We focus on the role of diffusive and advective transport by galactic winds, either driven by turbulent or thermal instabilities. We compare model predictions to observations, for which we compile a homogeneous set of luminosities in these radio bands, and update those available in gamma-rays. Our model reproduces reasonably well the observed relations between the gamma-ray or 1.4 GHz radio luminosities and the SFR, assuming a single power-law scaling of the magnetic field with the latter with index beta=0.3, and winds blowing either at Alfvenic speeds or typical starburst wind velocities. Escape of CR is negligible for > 30 Mo/yr. A constant ionisation fraction of the interstellar medium fails to reproduce the 150 MHz radio luminosity throughout the whole SFR range. Our results reinforce the idea that galaxies with high SFR are CR calorimeters, and that the main mechanism driving proton escape is diffusion, whereas electron escape also proceeds via wind advection. They also suggest that these winds should be CR or thermally-driven at low and intermediate SFR, respectively. Our results globally support that magnetohydrodynamic turbulence is responsible for the dependence of the magnetic field strength on the SFR and that the ionisation fraction is strongly disfavoured to be constant throughout the whole SFR range.Comment: Submitted to Astronomy & Astrophysics (on 12/05/2021

Multi-zone non-thermal radiative model for stellar bowshocks

Context. Runaway stars produce bowshocks that are usually observed at infrared (IR) wavelengths. Non-thermal radio emission has been detected so far only from the bowshock of BD+43°3654, whereas the detection of non-thermal radiation from these bowshocks at high energies remains elusive. Aims. We aim at characterising in detail the radio, X-ray, and γ-ray emission from stellar bowshocks accounting for the structure of the region of interaction between the stellar wind and its environment. Methods. We develop a broadband-radiative, multi-zone model for stellar bowshocks that takes into account the spatial structure of the emitting region and the observational constraints. The model predicts the evolution and the emission of the relativistic particles accelerated and streaming together with the shocked flow. Results. We present broadband non-thermal spectral energy distributions for different scenarios, synthetic radio-cm synchrotron maps that reproduce the morphology of BD+43°3654, and updated predictions in X-ray and γ-ray energy ranges. We also compare the results of the multi-zone model applied in this work with those of a refined one-zone model. Conclusions. A multi-zone model provides better constraints than a one-zone model on the relevant parameters, namely the magnetic field intensity and the amount of energy deposited in non-thermal particles. However, one-zone models can be improved by carefully characterising the intensity of the IR dust photon field and the escape rate of the plasma from the shocked region. Finally, comparing observed radio maps with those obtained from a multi-zone model enables constraints to be obtained on the direction of stellar motion with respect to the observer

Synchrotron radiation and absence of linear polarization in the colliding wind binary WR 146

Context. Several massive early-type binaries exhibit non-thermal emission which has been attributed to synchrotron radiation from particles accelerated by diffusive shock acceleration (DSA) in the wind-collision region (WCR). If the magnetic field in the strong shocks is ordered, its component parallel to the shock front should be enhanced, and the resultant synchrotron radiation would be polarized. However, such polarization has never been measured. Aims. We aim to determine the percentage of linearly polarized emission from the well-known non-thermal radio emitter WR 146, a WC6+O8 system. Methods. We performed spatially-unresolved radio continuum observations of WR 146 at 5 cm and 20 cm with the Karl G. Jansky Very Large Array. We constructed a numerical model to investigate a scenario where particles are accelerated by turbulent magnetic reconnection (MR), and we performed a quantitative analysis of possible depolarization effects. Results. No linearly polarized radio emission was detected. The data constrain the fractional linear polarization to less than 0.6% between 1 to 8 GHz. This is compatible with a high level of turbulence and a dominant random component in the magnetic field. In this case the relativistic particles could be produced by turbulent magnetic reconnection. In order for this scenario to satisfy the required non-thermal energy budget, the strength of the magnetic field in the WCR must be as high as ∼ 150 mG. However, if the magnetic field is ordered and DSA is ongoing, then a combination of internal and external Faraday rotation could equally account for the depolarization of the emission. Conclusions. The absence of polarization could be caused by a highly turbulent magnetic field, other depolarization mechanisms such as Faraday rotation in the stellar wind, or a combination of these processes. It is not clear whether it is possible to develop the high level of turbulence and strong magnetic fields required for efficient MR in a long-period binary such as WR 146. This scenario might also have trouble explaining the low-frequency cutoff in the spectrum. We therefore favor a scenario where particles are accelerated through DSA and the depolarization is produced by mechanisms other than a large ratio between random to regular magnetic fields.Facultad de Ciencias Astronómicas y GeofísicasInstituto Argentino de Radioastronomí

Evidence for non-thermal X-ray emission from the double Wolf-Rayet colliding-wind binary Apep

Context. Massive colliding-wind binaries (CWBs) can be non-thermal sources. The emission produced in their wind-collision region (WCR) encodes information of both the shock properties and the relativistic electrons accelerated in them. The recently discovered system Apep, a unique massive system hosting two Wolf-Rayet stars, is the most powerful synchrotron radio emitter among the known CWBs. It is an exciting candidate in which to investigate the non-thermal processes associated with stellar wind shocks. Aims. We intend to break the degeneracy between the relativistic particle population and the magnetic field strength in the WCR of Apep by probing its hard X-ray spectrum, where inverse-Compton (IC) emission is expected to dominate. Methods. We observed Apep with NuSTAR for 60 ks and combined this with a reanalysis of a deep archival XMM-Newton observation to better constrain the X-ray spectrum. We used a non-thermal emission model to derive physical parameters from the results. Results. We detect hard X-ray emission consistent with a power-law component from Apep. This is compatible with IC emission produced in the WCR for a magnetic field of ≈105–190 mG, corresponding to a magnetic-to-thermal pressure ratio in the shocks of ≈0.007–0.021, and a fraction of ∼1.5 × 10−4 of the total wind kinetic power being transferred to relativistic electrons. Conclusions. The non-thermal emission from a CWB is detected for the first time in radio and at high energies. This allows us to derive the most robust constraints so far for the particle acceleration efficiency and magnetic field intensity in a CWB, reducing the typical uncertainty of a few orders of magnitude to just within a factor of a few. This constitutes an important step forward in our characterisation of the physical properties of CWBs

Secondary hyperparathyroidism in HIV-infected patients: relationship with bone remodeling and response to vitamin D supplementation

Purpose of the study: Secondary hyperparathyroidism (SH) is frequent in HIV-infected patients. However, the causes and consequences are not well established. The aim of our study was to determine the relationship between parathyroid hormone (PTH), vitamin D and bone mineral density (BMD) in HIV-infected patients, and the effect of vitamin D replacement on PTH levels. Methods: Prospective study of 506 patients with at least two sequential serum determinations of PTH and 25-hydroxyvitamin D levels. In all cases, a bone dual X-ray absorptiometry (DEXA) was performed at inclusion. Hyperparathyroidism was defined as a PTH level above 65 pg/ml. Summary of results: Mean age was 44 yrs (24–78), and 75% were male. Mean BMI was 23.7 (17.97–33.11), and only 3% were of black race. Median nadir CD4+ was 200 cells/µL (9–499), and median time of HIV infection was 15.3 yrs (1.7–25.2). At inclusion, 488 patients (86%) were on HAART (31% TDF+PI, 44% TDF+NNRTI, 25% non-TDF based regimen) for a median of 929.5 days (154–1969), and 40% were HCV-coinfected. Median eGFR was 97.9 ml/min (62.14–134.08). Overall, mean serum PTH was 56.3 pg/mL (27.2–95.07). SH was observed in 27% of cases, with a marked influence of seasonality (from 44% in January to 10% in August). Mean levels of vitamin D were 17.45 ng/mL (7.6–40.78), with 16% below 10 ng/ml, 59%<20 ng/ml (deficiency), 85%<30 ng/ml (insufficiency). SH was related to vitamin D deficiency (relative risk, RR, 2.44), age (RR 1.04 per year), and a higher decrease in eGFR (RR 1.03 per ml/min), after adjustment by season, antiretroviral therapy, GFR at baseline, and HCV coinfection. DEXA scan showed 18% osteoporosis and 54% osteopenia, and there was an inverse correlation between PTH levels and T and Z score in femoral neck (r=−0.14, p<0.01), higher in those patients below 40 yrs. Vitamin D supplementation in 181 patients produced a significant decrease in serum PTH (57.2 if not treated vs 50.5 pg/ml, p=0.02, 23% continues with SH) and the only factor associated with lack of response was persistent vitamin D deficiency. Conclusion: SH is relatively frequent in HIV patients, in close relation with vitamin D deficiency. It is associated with bone resorption, especially in the femoral neck. The use of vitamin D supplementation improves SH when levels above 20 ng/ml are achieved

Odonata from Iberá Wetland System (Corrientes, Argentina) Are Regional Biogeographic Schemes Useful to Assess Odonata Biodiversity and Its Conservation?

Regionalization schemes reflect different macroscale distribution patterns and show large areas characterized by a common natural history, resulting in similar associations of biotic and abiotic features. Freshwater biota and terrestrial biota do not respond in the same way to environmental variables. The Iberá Depression, one of the largest wetlands in South America, is recognized in many schemes either as a functional unit or as an area with an ecotonal character. We used the distributional data of 128 species of Odonata, from a total of 103 collection sites from Corrientes and Misiones provinces, to test if Iberá functions as an ecological and functional unit, based on the Odonata distribution patterns. In addition, we tested if their distribution patterns fit into the most widespread regionalization schemes (hydrological basins, biogeographical provinces and ecoregions) used in Argentina. The Iberá Depression was not recovered as a functional unit; its sub-basins are more related to external basins than to each other. Neither the ecoregion nor the biogeographical schemes are suitable to explain the distribution patterns of the Odonata. The Odonata seem to respond to the availability of particular wetlands (e.g., ponds, streams, rivers, swamps, etc.), or to specific physical characteristics, such as the type of sediment, the availability of oxygen, etc., instead of to biogeographical or ecoregional schemes.Fil: del Palacio, Alejandro. Laboratorio de Biodiversidad y Genetica Ambiental (biogea) ; Departamento de Ambiente y Turismo ; Universidad Nacional de Avellaneda; . Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lozano, Federico. Laboratorio de Biodiversidad y Genetica Ambiental (biogea) ; Departamento de Ambiente y Turismo ; Universidad Nacional de Avellaneda; . Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ramos, Lia S.. Laboratorio de Biodiversidad y Genetica Ambiental (biogea) ; Departamento de Ambiente y Turismo ; Universidad Nacional de Avellaneda;Fil: Navarro, María de Las Mercedes. Laboratorio de Biodiversidad y Genetica Ambiental (biogea) ; Departamento de Ambiente y Turismo ; Universidad Nacional de Avellaneda;Fil: Muzon, Javier. Laboratorio de Biodiversidad y Genetica Ambiental (biogea) ; Departamento de Ambiente y Turismo ; Universidad Nacional de Avellaneda; . Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin