Illuminating Massive Black Holes With White Dwarfs: Orbital Dynamics and High Energy Transients from Tidal Interactions

White dwarfs (WDs) can be tidally disrupted only by massive black holes (MBHs) with masses less than $\sim10^5 M_\odot$. These tidal interactions feed material to the MBH well above its Eddington limit, with the potential to launch a relativistic jet. The corresponding beamed emission is a promising signpost to an otherwise quiescent MBH of relatively low mass. We show that the mass transfer history, and thus the lightcurve, are quite different when the disruptive orbit is parabolic, eccentric, or circular. The mass lost each orbit exponentiates in the eccentric-orbit case leading to the destruction of the WD after several tens of orbits. We examine the stellar dynamics of clusters surrounding MBHs to show that single-passage WD disruptions are substantially more common than repeating encounters. The $10^{49}$ erg s$^{-1}$ peak luminosity of these events makes them visible to cosmological distances. They may be detectible at rates of as many as tens per year by instruments like Swift. In fact, WD-disruption transients significantly outshine their main-sequence star counterparts, and are the most likely tidal interaction to be detected arising from MBHs with masses less than $10^5 M_\odot$. The detection or non-detection of such WD-disruption transients by Swift is, therefore, a powerful tool to constrain lower end of the MBH mass function. The emerging class of ultra-long gamma ray bursts all have peak luminosities and durations reminiscent of WD disruptions, offering a hint that WD-disruption transients may already be present in existing datasets.Comment: Revised following response from refere

Diagnostic effectiveness of high-sensitivity troponins

Background: Acute myocardial infarctions (AMI) are a leading cause of death in the United States. The key to increasing survivability is early recognition to expedite the proper treatment modalities. In conjunction with the clinical presentation and electrocardiograms, the use of cardiac biomarkers is exponentially important in not only recognizing a cardiac event but also determining the extent of injury. Advancement in laboratory technology has led to the development of high-sensitive troponin (hs-troponin) assays which can detect smaller cardiac troponin serum levels compared to conventional troponin assays. This implies that the use of hs-troponin assays is more effective in the early detection and extent of tissue ischemia, increasing the chances of AMI survival. Objective: The purpose of this review is to determine whether the use of hs-troponin assays have a superior diagnostic value compared to conventional troponin assays in earlier identification or ruling-out AMI in patients who present with chest pain or other AMI symptoms. Methods: A PubMed search was conducted using the following search terms and filters: high-sensitive troponin, cardiac biomarkers, hs-troponin vs. conventional troponin, articles in the last 10 years, English language, randomized control trials, meta-analysis reviews. Articles were excluded if direct comparison between hs-troponin and conventional was not observed, no full text of the article was available, and low participant numbers. Conclusion: While their use is not fully adopted in the United States, hs-troponin assays can detect lower concentrations of serum troponin levels at the time of presentation compared to conventional assays, which increases their sensitivity but comes with a reduction in specificity. This is promising in early recognition of tissue ischemia and can lead to earlier detection of an AMI and expedite proper treatment pathways but raises the concern of an increase in AMI over diagnosis that may be factitious. When collected as serial markers, the hs-sensitivity troponins were equal with conventional assays in their sensitivity/specificity, which leads to the determination that they are no more effective in cardiac monitoring compared to conventional testing

Methods for Inactivating PEDV in Hog Trailers

Porcine epidemic diarrhea (PED) was first described in England in 1971 in growing pigs and the causative agent, porcine epidemic diarrhea virus (PEDV), was identified in 1978. The virus spread to the rest of Europe where it caused outbreaks of diarrhea and significant losses throughout the 1970s and 1980s. PEDV is considered endemic to Europe today, but does not cause widespread significant disease. In parts of Asia outbreaks were recognized first in 1982 and have continued to occur since. In May of 2013 PEDV was identified in swine for the first time in the United States. The virus has caused severe diarrhea in sows and piglets, with near 100% mortality in piglets across a wide geographical area of the United States. Genetic analysis of PEDV isolates from affected farms in the US found the virus to be 99% genetically similar to isolates from China, but efforts to determine the source of entry to the United States have been unsuccessful

Therapists\u27 Comfort Level in Providing Psychotherapy in Home-Based Therapy Settings

Home-based psychotherapy has expanded in the mental health community; however, little was known about the therapists\u27 comfort level in a home-based venue. The purpose of this quantitative study was to assess therapists\u27 comfort level (TCL) in providing psychotherapy in a home-based setting and how therapeutic competency (TC), therapeutic relationship (TR), and advanced therapeutic training (ATT) related to the comfort level. The social-ecological systems theory and the theory of comfort served as the theoretical frameworks. The present study used the Therapist Comfort Scale, Counseling Competencies Scale-Revised, the Scale to Assess Therapeutic Relationship in Community Mental Health Care-Clinician, and a demographic questionnaire. A multiple linear regression and correlational analysis were conducted to assess the predictive relationships among the variables. The participants were 76 therapists who provided psychotherapy in a home-based setting. The results revealed a statistically significant positive relationship between TCL and TR. This finding indicated that as the TR score increased, TCL also increased. There was a statistically significant positive relationship between TCL and TC, which indicated that as the TC score increased, TCL also increased. There was a statistically significant positive relationship between TCL and ATT, which indicated that as the ATT score increased, TCL also increased. It was hoped that this study\u27s findings can serve to inform and guide the home-based psychotherapists to improve their therapeutic relationship. Once the therapeutic relationship is formed, the therapists will obtain a high level of comfort in discussing concerns openly with the patients, and parents/caregivers. In addition, when therapists reach a high level of comfort, it could make a positive difference in the patients\u27 treatment outcomes. Thus, the findings of this study initiated positive social change at the level of the individual home-based therapist as well as to the vulnerable population that they serve

Estilo de liderazgo y su relación con el desempeño laboral de los colaboradores de una empresa contratista minera en Cajamarca 2019

RESUMEN El presente estudio tuvo como objetivo determinar la relación entre los estilos de liderazgo y el desempeño laboral de los colaboradores de una empresa contratista minera en Cajamarca 2019. La presente investigación tiene un estudio de tipo cualitativo y correlacional. La hipótesis planteada es el estilo de liderazgo de los gerentes se relaciona significativamente con el desempeño laboral del personal en una empresa contratista minera en Cajamarca. Para contrastar la hipótesis de investigación se utilizó el diseño no experimental con prueba estadística de Sperman, que nos sirve para determinar la relación entre dos variables que han sido clasificadas por orden y como métodos: inductivo-deductivo y en técnicas e instrumentos, se elaboró 2 encuestas dirigidas al personal de la empresa, las cuales fueron debidamente validadas y luego aplicadas en la empresa en estudio. La población es de: 10 colaboradores, a quiénes se les aplicó Test de Liderazgo de Kurt y Lewin y otra de desempeño. Del resultado de los datos, se concluye que el estilo de liderazgo de los gerentes se relaciona en el desempeño laboral del personal en una empresa contratista minera de la ciudad de Cajamarca. Se puede precisar, entonces, que el estilo de liderazgo de los gerentes se relaciona significativamente con el desempeño laboral del personal en una empresa contratista minera en Cajamarca; es decir, un buen estilo de liderazgo de los gerentes se obtienen valores altos en el nivel de desempeño del personal. La propuesta que se aplica para mejorar el desempeño laboral del personal es un estilo de liderazgo democrático. PALABRAS CLAVE: colaboradores, estilos de liderazgo, desempeño laboral, dimensión y relación.Abstract The objective of this study was to determine the relationship between leadership styles and the job performance of workers of a mining contractor company in Cajamarca 2019. The present investigation has a qualitative and correlational study. The proposed hypothesis is the leadership style of the managers is significantly related to the work performance of the personnel in a mining contractor company in Cajamarca. To test the research hypothesis, the non-experimental design with Sperman's statistical test was used, which helps us to determine the relationship between two variables that have been classified by order and as methods: inductive-deductive and in techniques and instruments, it was elaborated 2 surveys directed to the company's personnel, which were duly validated and then applied in the company under study. The population is of: 10 workers, to whom Kurt and Lewin's Leadership Test was applied and another of performance. From the result of the data, it is concluded that the leadership style of the managers is related to the work performance of the personnel in a mining contractor company in the city of Cajamarca. It can be pointed out, then, that the leadership style of the managers is significantly related to the work performance of the personnel in a mining contractor company in Cajamarca; that is, a good leadership style of the managers, high values are obtained in the level of staff performance. The proposal that is applied to improve the work performance of the personnel is a democratic leadership style

Lignocellulosic Crops in Europe: Integrating Crop Yield Potentials with Land Potentials

Given the ambitious EU targets to further decarbonise the economy, it can be expected that the demand for lignocellulosic biomass will continue to grow. Provisioning of part of this biomass by dedicated biomass crops becomes an option. This study presents integrated approach for crop allocation based on land availability and crop requirements. The model analysis to investigate the potential extension of unused land and its suitability for lignocellulosic crops was carried out in 37 European countries at the NUTS3 level. The CAPRI model predicts future land use changes and was used as a basic input to assess the agricultural biomass potentials in Europe. It was then identified the total land resource with a post-modeling assessment for three different potentials to the year 2020 and 2030, according to sustainability criteria formulated in the Renewable Energy directive (RED). Furthermore, crop-specific suitability maps were generated for each crop based on the variability of biophysical factors such as climate, soil properties and topographical aspects. The yields and cost levels that can be reached in Europe with different perennial crops in different climatic, soil and management situations. The AquaCrop model developed by FAO was used and fed with phenological parameters per crop and detailed weather data to simulate the crop growth in all European Nuts 3 regions. Yield levels were simulated for a maximum and a water-limited yield situation and further converted to match with low, medium and high input management systems. The costs production was assessed with an Activity Based Costing (ABC) model, developed to assess the roadside Net Present Value (NPV) cost of biomass. The yield, crop suitability and cost simulation results were then combined to identify the best performing crop-management mix per region

Spectrophotometric determination of the formation constants of calcium(II) complexes with 2,2'-bipyridyl and 1,10-phenanthroline in acetonitrile

The oxygen-evolving complex (OEC), which consists of a calcium-manganese cluster, is the reaction center of the Photosystem II. At this catalytic site, the water-splitting reaction in dioxygen and hydronium ions occurs. In order to partially reproduce the water splitting process, several studies have reported the synthesis of functional model complexes. Nevertheless, there is a small amount of reports, concerning the spectral behavior of calcium complexes or the calcium role in the cluster. In this work, in order to explore the absorption spectrum of calcium species in acetonitrile, an equilibrium study of the calcium complexes with 2,2'-bipyridyl or 1,10-phenanthroline, was carried out. The formation constants and the calculated electronic spectrum of each complex was obtained by a modified method of continuous variations consisting in a correlation of the experimental spectrophotometric data with the HypSpec software. The values of the formation constants for the calcium(II) complexes with 2,2'-bipyridyl and 1,10-phenanthroline, are Log β110 = 4.39 ± 0.02 and Log β110 = 5.94 ± 0.05, respectively

Mexican Medicinal Plants as an Alternative for the Development of New Compounds Against Protozoan Parasites

The protozoan parasites Plasmodium, Leishmania, Trypanosoma, Entamoeba histolytica, Giardia lamblia, and Trichomonas vaginalis, cause high morbidity and mortality in developed and developing countries. P. falciparum is responsible for malaria, one of the most severe infectious diseases in Africa. Hundreds of million people are affected by Trypanosoma and Leishmania that cause African and South American trypanosomiasis, and leishmaniasis. E. histolytica and G. lamblia contribute to the enormous burden of diarrheal diseases worldwide; trichomoniasis is the most common nonviral sexually transmitted disease in the world. Because of the important side effects of current treatments and the decrease in drug susceptibility, there is a renewed interest for the search of therapeutic alternatives against these pathogens. Natural products obtained from medicinal plants and their derivatives have been recognized for many years as a source of therapeutic agents. There are numerous reports about medicinal plants that are used by indigenous communities to treat gastrointestinal complaints. Importantly, phytochemical studies have allowed the identification of several secondary metabolites with anti-parasite activity. Our review revealed that Mexican medicinal plants have a great potential for the identification of new molecules with activity against protozoan parasites of medical importance worldwide and their potential use as new therapeutic compounds

Gobernanza educativa desde la política pública hasta el aula de clase en una perspectiva crítica y emancipatoria

En este articulo son discutidos sentidos atribuidos a la finalidad educativa del estudio en la escuela, entendiendo que su especificidad hace parte de una compleja red de relaciones en la cual las políticas públicas y los procesos de gobernanza educacional hacen parte.   Se trata de un estudio de carácter analítico descriptivo, organizado como un ensayo teórico sobre el tema de gobernanza en el ámbito de la educación, con atención orientada para una perspectiva crítica y emancipatoria. Es asumido un concepto de gobernanza educativa que articula la relación de interfase entre el escenario general de las redes de políticas públicas y el contexto local de cada escuela, vinculado con realidades problemáticas de vulnerabilidad social a ser resignificadas en las prácticas en el aula, en medio de la actual reforma curricular en Brasil. Resultados señalan la importancia de avanzar en el estudio y construcción de una gobernanza educativa critica, reflexiva y libertadora, contextualizada tanto en las redes de políticas públicas, como en las prácticas en condiciones pedagógicas reales, que contribuya en la consecución de una educación propulsora de la integralidad del desarrollo social civilizatorio, esencia y finalidad en la escuela humanizadora de la vida en sociedad.This article discusses meanings attributed to the educational purpose of studying at school, and it considers that its specificity is part of a complex network of relations of which the public policies and educational governance processes are part. It is a study of descriptive analytical character, organized as a theoretical essay on the theme of governance in the field of education, with attention turned to a critical and emancipatory perspective. The concept of educational governance adopted considers that it articulates the interface relationship between the general scenario of public policy networks and the local context of each school, linked with problematic realities of social vulnerability to be resignified in classroom practices, in the midst of the current curriculum reform happening in Brazil. Results signal the importance of moving forward in the study and construction of a critical, reflective, and liberating educational governance, contextualized both in the public policy networks and in the practices in real teaching conditions, and which contributes to the achievement of an education that promotes the integrality of the civilizing social development, essence and goal of the humanizing school of life in society.São aqui discutidos sentidos atribuídos à finalidade educativa do estudo na escola, entendendo que sua especificidade faz parte de uma complexa rede de relações na qual as políticas públicas e os processos de governança educacional fazem parte. Trata-se de um estudo de caráter analítico descritivo, organizado como um ensaio teórico sobre o tema da governança no âmbito da educação, com atenção voltada para uma perspectiva crítica e emancipatória. É assumido um conceito de governança educativa que articula a relação de interface entre o cenário geral das redes de políticas públicas e o contexto local de cada escola, vinculado com realidades problemáticas de vulnerabilidade social a serem ressignificadas nas práticas em sala de aula, em meio da atual reforma curricular no Brasil. Resultados sinalizam a importância de avançar no estudo e construção de uma governança educativa crítica, reflexiva e libertadora, contextualizada tanto nas redes de políticas públicas, quanto nas práticas em condições pedagógicas reais, que contribua na consecução de uma educação propulsora da integralidade do desenvolvimento social civilizatório, essência e finalidade na escola humanizadora da vida em sociedade.&nbsp