Effect of strontium and cooling rate upon eutectic temperatures of A319 aluminum alloy

DTA analysis was used to investigate the solidification reactions of alloy A319 with either 12 or 136 ppm of Sr added. Strontium does not affect primary solidification of (Al) dendrites but modifies the kinetics of the (Al)–Si eutectic. The effects of Sr level and of cooling rate on the characteristic temperatures for the (Al)–Si and other eutectic reactions are described

Mechanisms of Spontaneous and Amplified Spontaneous Emission in CH3 NH3 Pb I3 Perovskite Thin Films Integrated in an Optical Waveguide

In this paper, the physical mechanisms responsible for optical gain in CH3NH3PbI3 (MAPI) polycrystalline thin films are investigated experimentally and theoretically. Waveguide structures composed by a MAPI film embedded in between PMMA and silica layers are used as an efficient geometry to confine emitted light in MAPI films and minimize the energy threshold for amplified spontaneous emission (ASE). We show that photogenerated exciton density at the ASE threshold is as low as (2.4-12)×1016cm-3, which is below the Mott transition density reported for this material and the threshold transparency condition deduced with the free-carrier model. Such a low threshold indicates that the formation of excitons plays an important role in the generation of optical gain in MAPI films. The rate-equation model including gain is incorporated into a beam-propagation algorithm to describe waveguided spontaneous emission and ASE in MAPI films, while using the optical parameters experimentally determined in this work. This model is a useful tool to design active photonic devices based on MAPI and other metal-halide semiconductors

Prevalence of Resistant Strains of Rhipicephalus microplus to Acaricides in Cattle Ranch in the Tropical Region of Tecpan of Galeana, Guerrero, Mexico

Tick and tick borne diseases cause many problems to the cattle industry worldwide. The prevalence of resistant strains of Rhipicephalus microplus to different acaricides on cattle farms in the tropical region of Tecpan of Galeana, Guerrero, Mexico, and risk factors related to prevalence of resistant strains of R. microplus. Sixty one ranches infested were sampled; in each ranch were collected 30-50 fully-engorged female R. microplus ticks, of 10 cattle randomly selected, and evaluated in their progeny resistance to acaricides, using the larval packet test. The prevalence of resistant strains was total pyrethroids and amitraz. In organophosphorus 31.1, 48.3 and 82.2% of strains were resistant to clorpyriphos, coumaphos and diazinon, respectively. Risk factors favored (P<0.05) the development of resistant strains of acaricides. We concluded that the resistance of R. microplus to acaricides used to control a problem, and risk factors (livestock management) have accelerated the development of resistance

Asistencia farmacéutica a la prescripción para aproximar la práctica clínica a la evidencia científica

ObjetivoEl objetivo del presente estudio es valorar la utilidad de un programa de asistencia farmacéutica a la prescripción (AFP) en cuanto a la detección de problemas relacionados con los medicamentos.DiseñoRealizamos un estudio descriptivo de los hallazgos de este programa al cabo de 6 meses de rodaje.EmplazamientoEl trabajo fue realizado en 5 centros del Distrito Bahía-Cádiz de Atención Primaria.PacientesSe estudian todos los pacientes (499) incluidos a petición y criterio de su médico, que solicita asesoramiento sobre su farmacoterapia.IntervenciónImplantamos el programa de AFP en pacientes crónicos con dos finalidades básicas:1. Asistencial: detectar problemas relacionados con medicamentos y proponer soluciones individualizadas.2. Docente: aproximar los conocimientos en farmacoterapia aplicados en la práctica clínica a la evidencia científica disponible.Mediciones y resultadosNos centramos en la detección de aquellos problemas relacionados con medicamentos más frecuentes, con incidencia directa y relevante sobre la morbimortalidad. Detectamos 236 casos (47%) de posible mejora terapéutica con implicaciones importantes sobre morbilidad asociada, de los cuales 114 (23%) tenían también implicaciones sobre mortalidad. Un 56% de los pacientes recibía más de 4 medicamentos, polimedicación que podía reducirse fácilmente en un 43,5% de ellos, evitando la utilización de medicamentos de valor intrínseco no elevado.ConclusionesLa utilidad del programa resulta muy elevada al detectar numerosos problemas de gran relevancia clínica y aportar información que puede ser útil al médico para aproximar la farmacoterapia a la evidencia científica disponible.ObjectiveThe objective of this study is to assess the usefulness of a programme of attention to pharmaceutical prescriptions (APP) so as to detect medicine-related problems.DesignA descriptive study of the findings after six months operation of this programme.SettingFive primary care centres in the Bahía-Cádiz Area.PatientsAll the patients (499) who requested advice on their drug therapy and were included at the request and on the criterion of their doctor were studied.InterventionWe introduced the APP programme for chronic patients, with two basic aims:1. Care: to detect medicine-related problems and propose individual solutions.2. Teaching: to bring drug-therapy skills used in clinical practice into line with the scientific evidence available.Measurements and resultsWe focused on the detection of problems related to the most common medicines, with direct and relevant incidence on morbidity and mortality. We detected 236 cases (47%) of possible therapeutic improvement that had important implications for associated morbidity, of which 114 (23%) also had implications for mortality. 56% of the patients took more than 4 medicines, multiple medication that could easily be reduced in 43.5% of cases, so avoiding the use of medicines of low intrinsic value.ConclusionsThe programme was very useful, as numerous very clinically relevant problems were detected and information was gained that the doctor can use to bring drug therapy into line with the available scientific evidence

Impacto de la intervención farmacéutica en la adherencia al tratamiento antirretroviral en pacientes de un hospital de Lima (Perú)

Introducción: La atención farmacéutica mejora la adherencia del paciente al tratamiento, por lo que es necesario que el farmacéutico cuente con instrumentos para evaluarla y mejorarla mediante su intervención en el seguimiento farmacoterapéutico (SFT). Objetivos: Evaluar el impacto de la intervención farmacéutica en la mejora de la adherencia de los pacientes con virus de la inmunodeficiencia humana (VIH) y sida, e identificar los factores que influyen en ella y que pueden ser modificados por la intervención farmacéutica en el SFT. Métodos: Se realizó SFT durante 23 meses a 52 pacientes mayores de 18 años de edad, con tratamiento antirretroviral durante más de 3 meses, que dieron su consentimiento informado. La adherencia se evaluó con el CEAT-VIH (cuestionario para evaluar la adhesión al tratamiento antirretroviral) al inicio y al final de 6 meses de SFT. Resultados: La puntuación total del CEAT-VIH (p <0,05; intervalo de confianza del 95%), el cumplimiento del tratamiento (p <0,001) y la percepción del paciente respecto a su enfermedad y tratamiento antirretroviral (p <0,001) incrementaron significativamente su valor. La educación al paciente para incrementar la adherencia al tratamiento (46%) fue la intervención farmacéutica más frecuente. Conclusiones: Se demuestra que la intervención del farmacéutico, mediante el SFT, mejora la adherencia al tratamiento antirretroviral. El farmacéutico mejoró los aspectos de cumplimiento y percepción del paciente sobre su tratamiento y enfermedad. Los farmacéuticos pueden utilizar el CEAT-VIH como instrumento para evaluar la adherencia en la práctica del SFT

Impacto de la intervención farmacéutica en la adherencia al tratamiento antirretroviral en pacientes de un hospital de Lima (Perú)

Introducción: La atención farmacéutica mejora la adherencia del paciente al tratamiento, por lo que es necesario que el farmacéutico cuente con instrumentos para evaluarla y mejorarla mediante su intervención en el seguimiento farmacoterapéutico (SFT). Objetivos: Evaluar el impacto de la intervención farmacéutica en la mejora de la adherencia de los pacientes con virus de la inmunodeficiencia humana (VIH) y sida, e identificar los factores que influyen en ella y que pueden ser modificados por la intervención farmacéutica en el SFT. Métodos: Se realizó SFT durante 23 meses a 52 pacientes mayores de 18 años de edad, con tratamiento antirretroviral durante más de 3 meses, que dieron su consentimiento informado. La adherencia se evaluó con el CEAT-VIH (cuestionario para evaluar la adhesión al tratamiento antirretroviral) al inicio y al final de 6 meses de SFT. Resultados: La puntuación total del CEAT-VIH (p <0,05; intervalo de confianza del 95%), el cumplimiento del tratamiento (p <0,001) y la percepción del paciente respecto a su enfermedad y tratamiento antirretroviral (p <0,001) incrementaron significativamente su valor. La educación al paciente para incrementar la adherencia al tratamiento (46%) fue la intervención farmacéutica más frecuente. Conclusiones: Se demuestra que la intervención del farmacéutico, mediante el SFT, mejora la adherencia al tratamiento antirretroviral. El farmacéutico mejoró los aspectos de cumplimiento y percepción del paciente sobre su tratamiento y enfermedad. Los farmacéuticos pueden utilizar el CEAT-VIH como instrumento para evaluar la adherencia en la práctica del SFT

Muon counting using silicon photomultipliers in the AMIGA detector of the Pierre Auger observatory

AMIGA (Auger Muons and Infill for the Ground Array) is an upgrade of the Pierre Auger Observatory designed to extend its energy range of detection and to directly measure the muon content of the cosmic ray primary particle showers. The array will be formed by an infill of surface water-Cherenkov detectors associated with buried scintillation counters employed for muon counting. Each counter is composed of three scintillation modules, with a 10m(2) detection area per module. In this paper, a new generation of detectors, replacing the current multi-pixel photomultiplier tube (PMT) with silicon photo sensors (aka. SiPMs), is proposed. The selection of the new device and its front-end electronics is explained. A method to calibrate the counting system that ensures the performance of the detector is detailed. This method has the advantage of being able to be carried out in a remote place such as the one where the detectors are deployed. High efficiency results, i.e. 98% efficiency for the highest tested overvoltage, combined with a low probability of accidental counting (similar to 2 %), show a promising performance for this new system

Effect of dried distillers grains (DDGS) on diet digestibility, growth performance, and carcass characteristics in Creole wool lambs fed finishing diets

Dried corn distillers grains with solubles (DDGS) can partially replace grains and forages in diets for ruminants. The objective of this research was to evaluate the effect of replacing grains and soybean meal with DDGS (0%, 15%, 30% and 45%) in the diet of lambs. Thirty-two native lambs were used (initial bodyweight = 28.6 ± 2.19 kg) in a completely randomized design. Initial body weight was a co-variable, and the means were compared with the Tukey test. The dry matter intake was significantly higher in DDGS containing diet than in the control treatment. The daily weight gain was higher in the diets with 15% of DDGS compared with the control. Dry matter digestibility was lower by 7% with 45% of DDGS. The hot and cold carcass weights were significantly higher by 8% in DDGS treatments compared to the control. The inclusion of increasing levels of DDGS in the diet of fattening lambs increased their dry matter intake, improved carcass weight, and did not adversely affect carcass characteristics.Keywords: Carcass, by-products, animal production, ruminant nutritio

IMPRESS: Improving Engagement in Software Engineering Courses through Gamification

Software Engineering courses play an important role for preparing students with the right knowledge and attitude for software development in practice. The implication is far reaching, as the quality of the software that we use ultimately depends on the quality of the people that make them. Educating Software Engineering, however, is quite challenging, as the subject is not considered as most exciting by students, while teachers often have to deal with exploding number of students. The EU project IMPRESS seeks to explore the use of gamification in educating software engineering at the university level to improve students' engagement and hence their appreciation for the taught subjects. This paper presents the project, its objectives, and its current progress

Abrupt Convergence and Escape Behavior for Birth and Death Chains

We link two phenomena concerning the asymptotical behavior of stochastic processes: (i) abrupt convergence or cut-off phenomenon, and (ii) the escape behavior usually associated to exit from metastability. The former is characterized by convergence at asymptotically deterministic times, while the convergence times for the latter are exponentially distributed. We compare and study both phenomena for discrete-time birth-and-death chains on Z with drift towards zero. In particular, this includes energy-driven evolutions with energy functions in the form of a single well. Under suitable drift hypotheses, we show that there is both an abrupt convergence towards zero and escape behavior in the other direction. Furthermore, as the evolutions are reversible, the law of the final escape trajectory coincides with the time reverse of the law of cut-off paths. Thus, for evolutions defined by one-dimensional energy wells with sufficiently steep walls, cut-off and escape behavior are related by time inversion.Comment: 2 figure