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Abstract Wildlife conservation in Andean countries is a global priority because of the high levels of biodiversity and endemism. Historically, these countries have had limited resources to monitor wildlife (e.g., through genetic tools) and establish conservation programs. Focusing on the study and emblematic use of a few charismatic species has been a strategic approach to direct efforts for conservation and development planning. Consequently, the Andean bear is a flagship and umbrella species for highly biodiverse Andean countries like Ecuador. The few studies exploring the population genetics of this species have concluded that it has low genetic diversity and few units for conservation as populations appear to be well connected. However, these results might be attributed to ascertainment bias as studies have been performed with heterologous molecular markers. Here, using both mtDNA sequences and species-specific microsatellite markers, we show that Andean bears in Ecuador have population structure. Additionally, we found through the study of three Ecuadorian populations that the species might have a higher genetic diversity than we previously thought. These results could support the revision of research priorities, conservation, and planning strategies to improve connectivity for this species which occurs in crucial biodiversity hotspots.

The increase in the overall global temperature and its subsequent impact on extreme weather events are the most critical consequences of human activity. In this scenario, transportation plays a significant role in greenhouse gas (GHG) emissions, which are the main drivers of climate change. The decline of non-renewable energy sources, coupled with the aim of reducing GHG emissions from fossil fuels, has forced a shift towards a net-zero emissions economy. As an example of this transition, the European Union has set 2050 as the target for achieving carbon neutrality. Hydrogen (H2) is gaining increasing relevance as one of the most promising carbon-free energy vectors. If produced from renewable sources, it facilitates the integration of various alternative energy sources for achieving a carbon-neutral economy. Recently, interest in its application to the transportation sector has grown, including different power plant concepts, such as fuel cells or internal combustion engines. Despite exhibiting significant drawbacks, such as low density, combustion instabilities, and incompatibilities with certain materials, hydrogen is destined to become one of the future fuels. In this publication, experimental activities are reported that were conducted on a spark-ignition engine fueled with hydrogen at different operating points. The primary objective of this research is to gain a better understanding of the thermodynamic processes that control combustion and their effects on engine performance and pollutant emissions. The results show the emission levels, performance, and combustion characteristics under different conditions of dilution, load, and injection strategy and timing.

Stress is known to be associated with adverse health outcomes. The COVID-19 pandemic and its associated lockdowns are examples of chronic stressors. Lockdown measures inadvertently caused significant psychological distress and became a powerful source of anxiety/stress, sleep disturbances, nutritional changes and weight gain. Stress is known to impact women's health specifically, through hypothalamic-pituitary-gonadal (HPG) axis dysfunction and resultant ovulatory dysfunction. Such dysfunction may manifest in menstrual irregularities and/or infertility due to hypothalamic hypogonadism. Here, we review the key physiological mediators of stress and associated ovulatory dysfunction. The kisspeptinergic system is comprised of sets of neurons located in the hypothalamus, the rostral periventricular region of the third ventricle (RP3V) and the arcuate nucleus (ARC). This system links nutrition, reproductive signals and stress. It plays a key role in the function of the HPG axis. During chronic stress, the kisspeptinergic system affects the HPG axis, GnRH pulsatility, and, therefore, ovulation. Leptin, insulin and corticotrophin-releasing hormone (CRH) are thought to be additional key modulators in the behavioral responses to chronic stress and may contribute to stress-related ovulatory dysfunction. This mini-review also summarizes and appraises the available evidence on the negative impact of chronic stress as a result of the COVID-19 pandemic lockdowns. It proposes physiological mechanisms to explain the observed effects on women's reproductive health and well-being. The review suggests areas for future research.

Currently, the use of photovoltaic solar energy has increased considerably due to the development of new materials and the ease to produce them, which has significantly reduced its acquisition costs. Most commercial photovoltaic modules have a flat geometry and are manufactured using metal reinforcement plates and glass sheets, which limits their use in irregular surfaces such as roofs and facades (BIPV) and the transportation sector (VIPV). The purpose of this study is to analyze the design implications of curved photovoltaic surfaces using composite materials. Considering operation and maintenance requirements, the most suitable reinforcement and encapsulation materials are selected based on references and experimental tests. It was found that the maximum radius of curvature that a polycrystalline silicon cell with the dimensions of a SunPower C60 model can achieve is 6.51 m for a failure probability lower than 5 %, which allows us to define the maximum curvature that this photovoltaic surface can reach. Additionally, an analytical model of the reinforcement was implemented using macromechanical models in Matlab™, which was validated by the finite element method employing the composite materials module in Ansys®. Therefore, this paper presents a detailed analysis of the shear stresses between the layers and of the deformations generated in the curved solar panel reinforcement. Finally, under the operating conditions assumed here, carbon fiber presents the best structural behavior in the reinforcement material, while epoxy resin exhibits a better performance in the encapsulation material. These results can facilitate the manufacturing of curved photovoltaic surfaces.

El presente artículo procura, a partir de una descripción del modelo social y su recepción convencional, establecer reglas prácticas para superar los obstáculos existentes y asegurar el respeto del derecho a la accesibilidad universal para las personas con discapacidad. El objetivo central consiste en desmembrar la accesibilidad de modo tal que se permita entender sus alcances. Este entendimiento tendrá como importancia detectar las barreras y enfatizar la necesidad de una debida participación universal. La metodología será cualitativa, a cuyo fin se partirá de las bases generales para ir desentrañando en forma deductiva el concepto de la accesibilidad. La posible contribución está dirigida a determinar reglas prácticas que hagan factible un control más adecuado de la accesibilidad.

Las empresas periodísticas han comenzado a desarrollar nuevos modelos de negocio con el propósito de continuar haciendo del periodismo una industria rentable. Una de estas medidas, con un largo recorrido ya en el periodismo anglosajón, es el muro de pago o límite de visitas gratuitas en las ediciones digitales. El objetivo de esta investigación consiste en explorar, a través de un análisis de todos los tuits dirigidos a diario Sur durante la semana previa y primera semana desde la puesta en marcha de su muro de pago, la incidencia y reacción que generó esta medida entre sus lectores. Los resultados revelan que este asunto tuvo una incidencia moderada respecto a la interacción total, aunque la mayoría de los lectores muestran un rechazo (casi) unánime a la implantación del muro de pago. Este estudio invita a la reflexión sobre las demandas de los lectores, quienes usan las redes sociales como una vía para interactuar con los medios.

The achievement of a carbon-free emissions economy is one of the main goals to reduce climate change and its negative effects. Scientists and technological improvements have followed this trend, improving efficiency, and reducing carbon and other compounds that foment climate change. Since the main contributor of these emissions is transportation, detaching this sector from fossil fuels is a necessary step towards an environmentally friendly future. Therefore, an evaluation of alternative fuels will be needed to find a suitable replacement for traditional fossil-based fuels. In this scenario, hydrogen appears as a possible solution. However, the existence of the drawbacks associated with the application of H2-ICE redirects the solution to dual-fuel strategies, which consist of mixing different fuels, to reduce negative aspects of their separate use while enhancing the benefits. In this work, a new combustion modelling approach based on machine learning (ML) modeling is proposed for predicting the burning rate of different mixtures of methane (CH4) and hydrogen (H2). Laminar flame speed calculations have been performed to train the ML model, finding a faster way to obtain good results in comparison with actual models applied to SI engines in the virtual engine model framework.

In this note, we propose a new construction of cyclotomic p-adic L-functions that are attached to classical modular cuspidal eigenforms. This allows for us to cover most known cases to date and provides a method which is amenable to generalizations to automorphic forms on arbitrary groups. In the classical setting of GL2 over Q, this allows for us to construct the p-adic L-function in the so far uncovered extremal case, which arises under the unlikely hypothesis that p-th Hecke polynomial has a double root. Although Tate’s conjecture implies that this case should never take place for GL2/Q, the obvious generalization does exist in nature for Hilbert cusp forms over totally real number fields of even degree, and this article proposes a method that should adapt to this setting. We further study the admissibility and the interpolation properties of these extremal p-adic L-functionsLpext(f,s), and relate Lpext(f,s) to the two-variable p-adic L-function interpolating cyclotomic p-adic L-functions along a Coleman family.

Sex hormones significantly impact women's lives. Throughout the different stages of life, from menarche to menopause and all stages in between, women experience dramatic fluctuations in the levels of progesterone and estradiol, among other hormones. These fluctuations affect the body as a whole, including the central nervous system (CNS). In the CNS, sex hormones act via steroid receptors. They also have an effect on different neurotransmitters such as GABA, serotonin, dopamine, and glutamate. Additionally, studies show that sex hormones and their metabolites influence brain areas that regulate mood, behavior, and cognitive abilities. This review emphasizes the benefits a proper hormonal balance during the different stages of life has in the CNS. To achieve this goal, it is essential that hormone levels are evaluated considering a woman's age and ovulatory status, so that a correct diagnosis and treatment can be made. Knowledge of steroid hormone activity in the brain will give women and health providers an important tool for improving their health and well-being.

The purpose of this article is to analyse the initial training ofthe Primary Teacher in Special Education. Only the compulsory curriculum for all country in Special Education is studied. At the same time, a critical review of such situation ·is made, Finally, some prospectives remarks are made.

La importancia de determinar el sexo en especies monomórficas que viven en cautiverio conlleva a estrategias de apareamiento a fin de poder incentivar la reproducción. Existen métodos no moleculares de reconocimiento pero son factibles en edad adulta y mucho más difícil cuando son polluelos. Mediante la técnica molecular de PCR, se amplificó el gen de la Cromo Helicasa de Unión al ADN empleando los cebadores, 2550F/2718R. Por este método molecular se consiguió determinar el sexo en 19 de 23 especies de las cuales 3 son ejemplares de: Amazona aestiva, 1 de Pipile grayi, 1 de Bubo virginianus, 4 de Ara chloropterus, 6 de Crax fasciolata, 2 de Caracara plancus, 3 de Chauna torquata, 1 de Cariama cristata y 2 de Cairina moschata del Centro de Investigación de Animales Silvestres de ITAIPU binacional, del lado paraguayo. Nuestros resultados sugieren que el par de cebadores 2550F/2718R podría ser de utilidad para determinar el sexo en las especies estudiadas en el país.

En este artículo se presentan los resultados de un estudio empírico sobre las representaciones mentales del profesorado en relación con el fracaso escolar, llevado a cabo en Dublín, París y Zaragoza. Previamente se ofrecen una serie de reflexiones sobre el concepto de representaciones mentales y sobre la significación del fracaso escolar, las cuales tienen como misión encuadrar teóricamente los resultados de dicho estudio.

Los datos sobre los que vamos a apoyar nuestra crítica y posterior alternativa a nivel de modelos para la modificación de ciertas conductas docentes en el interior del aula y a lo largo de sus estrategias didácticas forman parte de una modesta investigación sobre el fracaso escolar en la E.G.B., en la que estamos trabajando desde hace varios años.

RESUMEN: El acto didáctico es un proceso comunicativo con una finalidad muy concreta. Obviamente, como todo acto comunicativo, requiere el uso del lenguaje. En este artículo se toma como punto de partida el papel del texto formulado por el profesor Rodríguez Diéguez y se complementa con una perspectiva neuropsicológica basada en el papel del lenguaje como regulador del pensamiento.ABSTRACT: The didactic action is a communicative process with a specific purpose. Obviously, as all communicative action, it requires the mediation of language. In this paper the role of the text, such as it was formulated by the professor Rodriguez Diéguez, is taken as starting point. Such point of view is complemented with a neuropsychological perspective based on the role of language as an important mediator of thinking.RÉSUMÉ: L'acte didactique est Lin procès comiminicatif avec Line finalité très concrète. Certainement, comme tout acte communicatif, il a besoin de l'usage dLi langage. Le contenu de cet article prends comme point de partie le rôle du texte fornuilé par le professeur RodrígLiez Diéguez, complementé avec Line perspective neuropsychologique appLiiée dans le rôle du langage comme régulateur de la pensée.

Background: Positive symptoms of schizophrenia are associated with significant difficulties in daily functioning, and these difficulties have been associated with impaired executive functions (EEFF). However, specific cognitive and socio-emotional executive deficits have not been fully established. Objective: The present study has several objectives. First, we aimed to examine the specific deficits in cognitive and socio-emotional EEFF in a group of patients with schizophrenia with a predominance of positive symptoms, as well as to determine if these patients present clinically significant scores in any of the three fronto-subcortical behavioral syndromes: Dorsolateral, Orbitofrontal, or Anterior Cingulate. Method: The sample consisted of 54 patients, 27 with a predominance of positive symptoms, and 27 healthy controls matched for gender, age, and education. The two groups completed four cognitive and three socio-emotional EEFF tasks. In the group of patients, positive symptoms were evaluated using the scale for the Evaluation of Positive Symptoms (SANS), while the behavioral alterations associated with the three fronto-subcortical syndromes were evaluated using the Frontal System Behavior Scale (FrSBe). Results: The patients, in comparison with a control group, presented specific deficits in cognitive and socio-emotional EEFF. In addition, a high percentage of patients presented clinically significant scores on the three fronto-subcortical syndromes. Conclusion: The affectation that these patients present, in terms of both cognitive and emotional components, highlights the importance of developing a neuropsychological EEFF intervention that promotes the recovery of the affected cognitive capacities and improves the social and emotional functioning of the affected patients.