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To date, several exoplanets have been found to orbit within the habitable zone of main sequence M stars (M dwarfs). These stars exhibit different levels of chromospheric activity that produces ultraviolet (UV) radiation. UV may be harmful to life, but it can also trigger reactions of prebiotic importance on the surface of a potentially habitable planet (PHP). We created a code to obtain the adenine yield for a known adenine synthesis route from diaminomaleonitrile (DAMN). We used computational methods to calculate the reaction coefficient rates (photolysis rate J and rate constant K) for the intermediate molecules DAMN, diaminofumaronitrile (DAFN), and 4-aminoimidazole-5-carbonitrile (AICN) of the adenine synthesis route. We used stellar UV sources and a mercury lamp to compare the theoretical results with experiments performed with lamps. The surface UV flux of planets in the habitable zone of two active M dwarfs (Proxima Centauri and AD Leonis) and the prebiotic Earth was calculated using the photochemical model ATMOS, considering a CO2-N2-H2O atmosphere. We obtained UV absorption coefficients for DAMN and DAFN and thermodynamic parameters that are useful for prebiotic chemistry studies. According to our results, experiments using UV lamps may underestimate the photolysis production of molecules of prebiotic importance. Our results indicate that photolysis reactions are fast with a yield of 50% of AICN in 10 s for the young Sun and ∼1 h for Proxima Centauri b. Planets around active M dwarfs may provide the most favorable environment for UV-mediated production of compounds relevant to the origins of life. The kinetic reaction AICN + HCN  adenine is the bottleneck of the pathway with reaction rates <10-22 L/(mol·s).

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Microbial communities have been explored in various terrestrial subsurface ecosystems, showing metabolic potentials that could generate noteworthy morphological and molecular biosignatures. Recent advancements in bioinformatic tools have allowed for descriptions of novel and yet-to-be cultivated microbial lineages in different ecosystems due to the genome reconstruction approach from metagenomic data. Using shotgun metagenomic data, we obtained metagenome-assembled genomes related to cultivated and yet-to-be cultivated prokaryotic lineages from a silica and iron-rich cave (Monte Cristo) in Minas Gerais State, Brazil. The Monte Cristo Cave has been shown to possess a high diversity of genes involved with different biogeochemical cycles, including reductive and oxidative pathways related to carbon, sulfur, nitrogen, and iron. Three genomes were selected for pangenomic analysis, assigned as Truepera sp., Ca. Methylomirabilis sp., and Ca. Koribacter sp. based on their lifestyles (radiation resistance, anaerobic methane oxidation, and potential iron oxidation). These bacteria exhibit genes involved with multiple DNA repair strategies, starvation, and stress response. Because these groups have few reference genomes deposited in databases, our study adds important genomic information about these lineages. The combination of techniques applied in this study allowed us to unveil the potential relationships between microbial genomes and their ecological processes with the cave mineralogy and highlight the lineages involved with anaerobic methane oxidation, iron oxidation, and radiation resistance as functional models for the search for extant life-forms outside our planet in silica- and iron-rich environments and potentially on Mars.

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Following the 2020 confinement due to the COVID-19 pandemic, housing has become the only safe place and this has exposed inequity in habitability. This research on the reality of confined households and the perception of their homes in the Mexican republic is based on a mixed participatory study, combining quantitative and qualitative approaches. The online questionnaire consisted of 58 questions in the quantitative approximation. The qualitative part required the provision of an image of the workspace, with testimonies and personal reflections. During the lockdown, all participants saw an increase in overall energy consumption; more than half reported not being in thermal comfort; and a third declared deficiencies in noise insulation. Regarding the perception of the telework/tele-study space, we found the following categories: bedrooms, living/dining rooms, studies and others. In addition, respondents had often adapted the workspace for both individual and shared use. In general, the households were satisfied with the size of their houses but would like landscaped spaces or better views outside. Confinement made housing the protective element against the pandemic. The consequences will have an effect globally, so new architectural design paradigms need to be rethought.

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Kepler-96 is an active solar-type star harboring a Super-Earth planet in close orbit. Its age of 2.3 gigayears is the same as the Sun when there was a considerable increase of oxygen in Earth's atmosphere due to micro-organisms living in the ocean. We present the analysis of superflares seen on the transit light curves of Kepler-96b. The model used here simulates the planetary transit in a flaring star. By fitting the observational data with this model, it is possible to infer the physical properties of the flares, such as their duration and the energy released. We found three flares within the energy range of superflares, where the biggest superflare observed was found to have an energy of 1.81 × 1029 J (1.81 × 1035 ergs). The goal is to analyze the biological impact of these superflares on a hypothetical Earth in the habitable zone of Kepler-96, assuming this planet has protection through different scenarios: an Archean and present-day atmospheres. Also, we compute the attenuation of the flare ultraviolet (UV) radiation through an Archean ocean. The conclusion is that considering the increase in the UV flux by the strongest superflare emission, Escherichia coli and Deinococcus radiodurans could survive on the surface of the planet only if there was an ozone layer present on the planet atmosphere. However, they could escape from the hazardous UV effects at a depth of 28 and 12 m below the ocean surface, respectively. For smaller superflares contribution, D. radiodurans could survive in the surface even in an Archean atmosphere with no ozone.

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A partir de una revisión bibliográfica exhaustiva sobre el tema de Mejoramiento Barrial y Urbano (MBU), se presenta a continuación una sinopsis crítica del panorama situacional de este modelo de intervención comunitaria en Costa Rica. Se realizó una recolección de información de fuentes documentales secundarias en bases de datos a nivel internacional sobre los temas de Mejoramiento Barrial y Urbano (MBU) y métodos de intervención participativos para el aprovechamiento de espacios públicos en zonas urbanas. Después de establecer y valorar los criterios de inclusión y exclusión, se seleccionaron seis de las publicaciones científicas recuperadas, relacionadas con el tema de interés, y se elaboraron informes analíticos críticos de cada una de ellas y en conjunto, para lo cual se utilizó una matriz cualitativa de entrada de datos. Los hallazgos sirven de precedente para inferir que la Salud Ambiental constituye el mejor indicador de la habitabilidad de los asentamientos humanos y, considerando que aún no se evalúan los beneficios a la salud de la implementación de procesos de Mejoramiento Barrial y Urbano en Costa Rica, constituye un reto y una oportunidad para la disciplina el involucramiento en el abordaje integral de este proceso en el país para contribuir a la reconstrucción social y participativa de la salud comunitaria.

From an exhaustive literature review on the subject of Neighborhood and Urban Improvement (MBU, by the Spanish acronym), a critical overview of the situational outlook of this model of community intervention in Costa Rica is presented below. A collection of information was carried out from secondary documentary sources internationally on issues of Neighborhood and Urban Improvement programs (MBU) and participatory intervention methods for the use of public spaces in urban areas. After establishing and evaluating the criteria for inclusion and exclusion, six of all the scientific publications recovered related to these topics were selected and subjected to critical analysis separately and altogether, for which a qualitative input data matrix was used. The findings serve as a precedent to infer that the Environmental Health is the best indicator of the livability of human settlements and, considering that the health benefits of implementing Neighborhood and Urban Improvement processes in Costa Rica are yet to be evaluated, it is a challenge and an opportunity for the discipline to get involved in a comprehensive approach to this process in the country to contribute to the social and participatory reconstruction of community health.

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The direct detection of reflected light from exoplanets is an excellent probe for the characterization of their atmospheres. The greatest challenge for this task is the low planet-to-star flux ratio, which even in the most favourable case is of the order of 10-4 in the optical. This ratio decreases even more for planets in their host's habitable zone, typically lower than 10-7. To reach the signal-to-noise level required for such detections, we propose to unleash the power of the Cross Correlation Function in combination with the collecting power of next generation observing facilities. The technique we propose has already yielded positive results by detecting the reflected spectral signature of 51 Pegasi b (see Martins et al. 2015). In this work, we attempted to infer the number of hours required for the detection of several planets in their host's habitable zone using the aforementioned technique from theoretical EELT observations. Our results show that for 5 of the selected planets it should be possible to directly recover their reflected spectral signature.

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Este trabalho apresenta a percepção de Qualidade de Vida no Trabalho (QVT) dos empreendedores de Incubadoras Tecnológicas de São Paulo. Para os empreendedores, abrir o próprio negócio está relacionado à busca de prazer no trabalho. A opção por empreender faz que aumente sua carga horária de trabalho e, dessa forma, descuide da saúde e das atividades de lazer. A pesquisa foi exploratória-descritiva, quali-quanti com aplicação de questionário BPSO-96 e quatro grupos focais. Conclui-se que os empreendedores estão satisfeitos com sua QVT, principalmente em sua dimensão organizacional e psicológica; atribuem à QVT um significado de realização pessoal por estarem desenvolvendo sua empresa com sucesso. Foi identificada uma nova categoria a habitabilidade para a QVT, relacionada ao contexto no qual a empresa é instalada.

This paper reflects on the perception of the Quality of Work Life (QWL) of entrepreneurs working with technological incubation projects in São Paulo State. For entrepreneurs, starting up their own business relates to the pursuit of pleasure at work. The choice of becoming an entrepreneur leads to an increase their working hours and neglect their health and leisure needs. For this exploratory-descriptive, qualitative and quantitative research the BPSO-96 questionnaire was applied with four focus groups. According to its findings, entrepreneurs were satisfied with the organizational and psychological aspects of their QWL and they attribute to QWL a sense of personal fulfillment due to developing their own business successfully. A new category of habitability was identified in relation to QWL, which is linked to the setting where the company is being set up.

Este trabajo presenta la percepción de Calidad de Vida en el Trabajo (CVT) de los emprendedores de Incubadoras Tecnológicas de São Paulo. Para los emprendedores, la apertura de su propia empresa está relacionada a la busca del placer en el trabajo. La decisión de emprender es aumentar sus horas de trabajo y el abandono de las actividades del ocio y de la salud. La investigación fue exploratoria y descriptiva, cualitativa y cuantitativa con la aplicación de cuestionario BPSO-96 y cuatro grupos focales. Se concluye que los emprendedores están satisfechos con su CVT en su dimensión organizacional y psicológica; atribuyen a CVT un significado de realización personal porque están desarrollando su negocio con éxito. Fue identificada una nueva categoría la habitabilidad para CVT, relacionada con el contexto donde está instalada la empresa.

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In the late eighties, Mercado and González (1991) developed the concept of Habitability, defined as the suitability of the built environment for its residents, focused on residential environments. The evidence suggests that housing habitability is an important aspect of social sustainability, as it affects family's quality of life, social climate and health. In this paper we sought to describe several studies that are supported by the Habitability Model which is considered a way of evaluating residential environments, related to a set of design variables and consequences for the inhabitants. The Model was first developed using Multidimensional Scaling, and later confirmed through Path Analysis. The Model shows a central global measure of habitability and three groups of variables surround it: emotional, symbolic and behavioral. The model seems to explain relationships between architectonic design and residential environmental evaluation through habitability, and family's social processes that are linked to sustainability. Practical and theoretical implications of the results are discussed.

A finales de los años ochenta, Mercado y González (1991) desarrollaron el concepto de habitabilidad, entendida ésta como la adecuación de un entorno construido para sus residentes, centrado en los entornos residenciales. La evidencia sugiere que la habitabilidad de una vivienda es un aspecto importante de la sostenibilidad social, puesto que afecta la calidad de vida de las familias, así como el clima social y la salud. En el presente trabajo nos dimos a la tarea de describir varios estudios que son compatibles con el modelo de habitabilidad; dicho modelo se considera una forma de evaluar los entornos residenciales en relación con un conjunto de variables de diseño y sus consecuencias para los habitantes. Se desarrolló el modelo por primera vez utilizando el escalamiento multidimensional, y luego se confirmó a través de Análisis de Ruta. El modelo muestra una medida global central de habitabilidad, así como tres grupos de variables que le rodean: las emocionales, las simbólicas, y las comportamentales. El modelo parece explicar las relaciones entre el diseño arquitectónico y la evaluación del entorno residencial a través de la habitabilidad y de los procesos sociales de la familia que están vinculados a la sostenibilidad. Se discuten las implicaciones prácticas y teóricas de los resultados.

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La formulación de bases conceptuales para una gestión integral del riesgo, parte de la identificación de las dinámicas de los desastres socio-naturales en los países en vía de desarrollo, de la definición de los elementos estructurales y su espacialización en el territorio de Pamplona, además de la formulación y aplicación de una metodología de recolección y análisis de información en el contexto específico diversos sitios de Pamplona evidenciados con una mayor amenaza y vulnerabilidad, a eventos de remoción en masa. Los lineamientos propuestos están soportados en la representación del sentido colectivo y de los intereses de los actores sociales del desarrollo, se fundamentan en la adaptabilidad, la habitabilidad y la incertidumbre, y son esenciales para la determinación de acciones de intervención en diferentes escalas de aproximación al territorio, las cuales, deben ser llevadas a una negociación de intereses en niveles de ejecución real y posible.

The formulation of conceptual bases for a comprehensive risk management, starts from the identification of the dynamics of social-natural disasters in developing countries, from the definition of structural elements and its spatialization in the territory of Pamplona, and from the formulation and implementation of a collecting and analyzing information methodology in the specific context in a variety of areas in Pamplona evidenced with more threat and vulnerability to landslide events. The proposed guidelines are supported on the representation of collective consciousness and the interests of social actors of development, based on the adaptability, habitability and uncertainty, and are the essence for the determination of intervention actions at different scales of approximation to the territory, which must be brought to a negotiation of interests in levels of real and possible performance.

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Este artículo tiene como objetivo enmarcar el tema del desarrollo humano y la calidad de vida dentro de la problemática urbana en una ciudad como Barranquilla (Colombia) y la urgente necesidad que existe en ésta por cumplir unos criterios de habitabilidad y convivencia social en un marco de desarrollo sostenible. Para esto se describen los problemas de la salud y su relación con el espacio urbano en la ciudad, luego se presenta el concepto de Desarrollo Humano y Calidad de Vida, así como de Habitabilidad. Se termina sugiriendo una perspectiva de análisis que integre todo lo anterior coherentemente al concepto de sostenibilidad, como una alternativa de generar una mayor calidad de vida, mayor desarrollo humano y mayor habitabilidad en la ciudad...

This article intends to place the topic of human development and quality of life within the urban problematic in Barranquilla, Colombia, and the urgent necessity to meet some habitability and convivential criteria, within a sustainable development framework. In order to accomplish this, health problems and their relationship with the urban space in the city are described, next the concept of Human Development and Quality of Life, and habitability in Barranquilla are presented. It finishes suggesting a new perspective of analysis which coherently integrates all the afore said to the sustainability concept, as an alternative to generate better quality of life, higher human development and higher habitability in the city...

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