Probing dissipation mechanisms in BL Lac jets through X-ray polarimetry

The dissipation of energy flux in blazar jets plays a key role in the acceleration of relativistic particles. Two possibilities are commonly considered for the dissipation processes, magnetic reconnection -- possibly triggered by instabilities in magnetically-dominated jets -- , or shocks -- for weakly magnetized flows. We consider the polarimetric features expected for the two scenarios analyzing the results of state-of-the-art simulations. For the magnetic reconnection scenario we conclude, using results from global relativistic MHD simulations, that the emission likely occurs in turbulent regions with unstructured magnetic fields, although the simulations do not allow us to draw firm conclusions. On the other hand, with local particle-in-cell simulations we show that, for shocks with a magnetic field geometry suitable for particle acceleration, the self-generated magnetic field at the shock front is predominantly orthogonal to the shock normal and becomes quasi-parallel downstream. Based on this result we develop a simplified model to calculate the frequency-dependent degree of polarization, assuming that high-energy particles are injected at the shock and cool downstream. We apply our results to HBLs, blazars with the maximum of their synchrotron output at UV-soft X-ray energies. While in the optical band the predicted degree of polarization is low, in the X-ray emission it can ideally reach 50\%, especially during active/flaring states. The comparison between measurements in the optical and in the X-ray band made during active states (feasible with the planned {\it IXPE} satellite) are expected to provide valuable constraints on the dissipation and acceleration processes.Comment: 9 pages, 6 figures, accepted for publication by MNRA

Improving Bowen-ratio estimates of evaporation using a rejection criterion and multiple-point statistics

The application of the Bowen ratio method to estimate evaporation is heavily affected by uncertainties on the measured quantities. Time series collected with a hydro-meteorological monitoring station often contain measurements for which a reliable estimate of evaporation cannot be computed. Such measurements can be identified with standard error propagation methods. However, simply discarding some values might introduce a bias in the cumulative evaporation for long time intervals, also depending on the threshold of acceptance. In this paper, we propose the use of multiple-point statistics simulation to integrate the time series of reliable evaporation estimates. A test conducted on a two-year-long time series of data collected with a hydro-meteorological station in the Po plain (Italy) shows that the usage of a rejection criteria in conjunction with multiple-point statistics simulation is a promising and useful tool for the reconstruction of reliable evaporation time series. In particular, it is shown that if the rejected values are not replaced by simulation, then the cumulative evaporation curves are estimated with a bias comparable with estimates of cumulative annual evaporation. Moreover, the test gives some insights for the selection of the best rejection threshold

Pharmacokinetics of erythromycin after intravenous, intramuscular and oral administration to cats

The aim of this study was to characterise the pharmacokinetic properties of different formulations of erythromycin in cats. Erythromycin was administered as lactobionate (4 mg/kg, intravenously (IV)), base (10 mg/kg, intramuscularly (IM)) and ethylsuccinate tablets or suspension (15 mg/kg, orally (PO)). After IV administration, the major pharmacokinetic parameters were (mean ± SD): area under the curve (AUC)(0-∞) 2.61 ± 1.52 µg.h/mL; volume of distribution (Vz) 2.34±1.76 L/kg; total body clearance (Clt) 2.10±1.37 L/h.kg; elimination half-life (t½λ) 0.75±0.09 h and mean residence time (MRT) 0.88±0.13 h. After intramuscular administration, the principal pharmacokinetic parameters were (mean ± DS): peak concentration (Cmax), 3.54±2.16 µg/mL; time of peak (Tmax), 1.22±0.67 h; t½λ, 1.94±0.21 h and MRT, 3.50±0.82 h. The administration of erythromycin ethylsuccinate (tablets and suspension) did not produce measurable serum concentrations. After IM and IV administrations, erythromycin serum concentrations were above minimum inhibitory concentration (MIC)90=0.5 µg/mL for 7 and 1.5 h, respectively. However, these results should be cautiously interpreted since tissue erythromycin concentrations have not been measured and, it is recognised that they can reach much higher concentrations than in blood, correlating better with clinical efficacy.Fil: Albarellos, G. A.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Montoya, L.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Landoni, Maria Fabiana. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Probing shock acceleration in BL Lac jets through X-ray polarimetry: the time-dependent view

Polarimetric measurements, especially if extended at high energy, are expected to provide important insights into the mechanisms underlying the acceleration of relativistic particles in jets. In a previous work we have shown that the polarization of the synchrotron X-ray emission produced by highly energetic electrons accelerated by a mildly relativistic shock carries essential imprints of the geometry and the structure of the magnetic fields in the downstream region. Here we present the extension of our analysis to the non-stationary case, especially suitable to model the highly variable emission of high-energy emitting BL Lacs. We anticipate a large ($\Pi \approx 40\%$), almost time-independent degree of polarization in the hard/medium X-ray band, a prediction soon testable with the upcoming mission {\it IXPE}. The situation in other bands, in particular in the optical, is more complex. A monotonic decrease of the optical degree of polarization is observed during the development of a flare. At later stages $\Pi$ reaches zero and then it starts to increase, recovering large values at late times. The instant at which $\Pi=0$ is marked by a rotation of the polarization angle by $90$ degrees. However, at optical frequencies it is likely that more than one region contributes to the observed emission, potentially making it difficult to detect the predicted behavior.Comment: 11 pages, 9 figures, accepted for publication by MNRA

Money management and entrepreneurial training in microfinance: impact on beneficiaries and institutions

This study uses a randomized control trial to evaluate the outcome of integrating money management and entrepreneurial training into a microcredit program in India. We find positive and significant effects on clients\u2019 financial management skills and entrepreneurship abilities, particularly for clients with higher human capital, or more diligent, or having an entrepreneurial idea, and an increase in initiative and self-confidence. Effects appear stronger for clients obliged to attend the training course or more interested in attending it. By considering missed or delayed repayments reduction we assess the benefits of the training provided and of extending it for the institution

Fostering savings by commitment: Evidence from a quasi-natural experiment at The Small Enterprise Foundation in South Africa

We studied the effects of a pilot project that strengthened savings incentive mechanisms. The project was established by The Small Enterprise Foundation (SEF), a leading microfinance institution based in South Africa. The program introduced a savings stimulus in the form of a Goal Card: clients subscribing to this (non-coercive) tool were required to identify a savings goal and to commit to regular payments to reach it. The experiment had a quasi-natural approach as it was implemented by SEF in non-randomly selected locations. Difference-in-differences estimates show improved savings habits among those of the foundation's customers who were involved in the program, compared to the counterfactual that are identified using propensity score matching. The effect of the program manifested in its second semester, suggesting a persistent change of habits but a slow accumulation of savings. We conclude that asking microcredit customers to identify a savings goal and commit to a regular savings amount to achieve it is a promising savings incentive mechanism

Caracterización fisicoquímica y estabilidad oxidativa de aceites comestibles de semillas de sacha inchi microencapsulados y secados por aspersión

The aim of this work was to obtain sacha inchi oil (SIO) microcapsules from two different species, Plukenetia volubilis L. (SIVO) and Plukenetia huayllabambana L. (SIHO), using different biopolymers as wall materials and spray drying technology. The physicochemical characteristics such as encapsulation efficiency, particle size, morphology and oxidative stability were analyzed in order to select the best formulation that could potentially be used as an ingredient in the development of functional food. Bulk SIO and four formulations were tested for each oil ecotype, using different encapsulating agents: maltodextrin (MD), Arabic gum (AG), whey protein concentrate (WPC) and modified starch HI-CAP®-100 (H). Microcapsules made of H presented the highest oxidative stability and encapsulation efficiency compared to AG, AG:MD or AG:MD:WPC formulations.El objetivo de este trabajo fue obtener microcápsulas de dos especies de aceite de sacha inchi (SIO), Plukenetia volubilis L. (SIVO) y Plukenetia huayllabambana L. (SIHO), utilizando diferentes biopolímeros como materiales de pared y la tecnología de secado por aspersión. Se analizaron tanto las características fisicoquímicas como la eficiencia de encapsulación, el tamaño de partícula, la morfología y la estabilidad oxidativa para seleccionar la mejor formulación que podría utilizarse como ingrediente en el desarrollo de alimentos funcionales. Se analizaron los aceites y cuatro formulaciones para cada ecotipo, usando diferentes agentes encapsulantes: maltodextrina (MD), goma Arábiga (AG), concentrado proteico de lactosuero (WPC) y almidón modificado HI-CAP®-100 (H). Las microcápsulas hechas con H presentaron la mayor estabilidad oxidativa y eficiencia de encapsulación en comparación con las formulaciones: AG; AG:MD o AG:MD:WPC

Ethical issues associated with in-hospital emergency from the medical emergency team's perspective: a national survey

Medical Emergency Teams (METs) are frequently involved in ethical issues associated to in-hospital emergencies, like decisions about end-of-life care and intensive care unit (ICU) admission. MET involvement offers both advantages and disadvantages, especially when an immediate decision must be made. We performed a survey among Italian intensivists/anesthesiologists evaluating MET's perspective on the most relevant ethical aspects faced in daily practice