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Various spatial modelling methods and tools have been used in ecology and biogeography. The application of these options serves a dual function: first, they offer information about the potential distribution of species to understand the richness and diversity of unassessed areas. Second, spatial modelling methods employ these predictions to select relevant sites to determine natural conservation areas. In this study, we compared three methods for modelling the spatial distribution of Egg-cone Pine (Pinus oocarpa Schiede), an important non-timber pine in Mexico. The final goal is to estimate suitable areas for the conservation and reproduction of superior individuals (plus trees) of P. oocarpa as a conservation strategy outside the known distribution since this species possesses a high ecological and economic value. The model used were a generalised linear model (GLM) as a parametric regression method, random forest (RF) as a machine-learning method, and the MaxEnt model, a standard procedure, implemented using the Kuenm R package. The results suggest that the models used performed well since the AUROC was between 0.95 and 0.98 in all cases. MaxEnt and random forest approaches provided more conservative predictions for the distribution of suitable areas of plus trees of P. oocarpa than the generalised linear model, but the random forest algorithm achieved the best performance. The results of the study allowed the determination of ex situ conservation areas for P. oocarpa plus trees outside of their known distribution.

Context. Protostellar jets are an important agent of star formation feedback, tightly connected with the mass-accretion process. The history of jet formation and mass ejection provides constraints on the mass accretion history and on the nature of the driving source. Aims. We characterize the time-variability of the mass-ejection phenomena at work in the class 0 protostellar phase in order to better understand the dynamics of the outflowing gas and bring more constraints on the origin of the jet chemical composition and the mass accretion history. Methods. Using the NOrthern Extended Millimeter Array (NOEMA) interferometer, we have observed the emission of the CO 2–1 and SO NJ = 54–43 rotational transitions at an angular resolution of 1.0 00 (820 au) and 0.400 (330 au), respectively, toward the intermediate mass class 0 protostellar system Cep E. Results. The CO high-velocity jet emission reveals a central component of ≤400 au diameter associated with high-velocity molecular knots that is also detected in SO, surrounded by a collimated layer of entrained gas. The gas layer appears to be accelerated along the main axis over a length scale δ0 ∼ 700 au, while its diameter gradually increases up to several 1000 au at 2000 au from the protostar. The jet is fragmented into 18 knots of mass ∼10−3 M, unevenly distributed between the northern and southern lobes, with velocity variations up to 15 km s−1 close to the protostar. This is well below the jet terminal velocities in the northern (+65 km s−1) and southern (-125 km s-1)lobes. The knot interval distribution is approximately bimodal on a timescale of ∼50–80 yr, which is close to the jet driving protostar Cep E-A and ∼150−20 yr at larger distances >1200. The mass-loss rates derived from knot masses are steady overall, with values of 2.7 x 10−5 M yr−1 and 8.9 x 10−6 M yr−1 in the northern and southern lobe, respectively. Conclusions. The interaction of the ambient protostellar material with high-velocity knots drives the formation of a molecular layer around the jet. This accounts for the higher mass-loss rate in the northern lobe. The jet dynamics are well accounted for by a simple precession model with a period of 2000 yr and a mass-ejection period of 55 yr. © Authors 2022 741002; National Science Foundation, NSF: AST-2102405; Horizon 2020 Framework Programme, H2020; H2020 Marie Skłodowska-Curie Actions, MSCA: 811312; European Research Council, ERC; Ministry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2020-0038; Centre National de la Recherche Scientifique, CNRS; Ural Federal University, UrFU interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). AS, BL, PR-RO, acknowledge support from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 811312 for the project “Astro-Chemical Origins” (ACO) and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program for the Project “The Dawn of Organic Chemistry” (DOC) grant agreement No 741002. DSC is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-2102405. A.V. and A.P. are the members of the Max Planck Partner Group at the Ural Federal University. A.P. and A.V. acknowledge the support of the Russian Ministry of Science and Education via the State Assignment Contract no. FEUZ-2020-0038. Based on observations carried out with the IRAM NOEMA interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). AS, BL, PR-RO, acknowledge support from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 811312 for the project "Astro-Chemical Origins" (ACO) and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program for the Project "The Dawn of Organic Chemistry" (DOC) grant agreement No 741002. DSC is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-2102405. A.V. and A.P. are the members of the Max Planck Partner Group at the Ural Federal University. A.P. and A.V. acknowledge the support of the Russian Ministry of Science and Education via the State Assignment Contract no. FEUZ-2020-0038.

Resumen: Introducción y objetivo: La obesidad se asocia con el hígado graso no alcohólico (HGNA) en niños. El objetivo fue explorar la asociación de factores dietéticos y sociodemográficos con el HGNA en niños y adolescentes obesos. Material y métodos: Treinta y tres pacientes obesos entre seis a 16 años fueron incluidos en este estudio transversal analítico. El diagnóstico de obesidad se realizó con puntuación z del índice de masa corporal > 2 DE. El HGNA se estimó con ultrasonido hepático, aminotransferasas séricas y elastografía. Las variables sociodemográficas se evaluaron con cuestionarios validados. La dieta se estimó mediante dos encuestas dietéticas por recordatorio de 24 horas enfocadas a la cantidad de energía, azúcares simples, ácidos grasos poliinsaturados (PUFAs) y antioxidantes. Resultados: En 13 pacientes (39.4%), se identificó esteatosis hepática por ultrasonido abdominal; 54.2% tuvieron una concentración sérica de alanina aminotransferasa por arriba de la referencia. El nivel educativo superior de ambos padres, el mayor gasto familiar mensual en alimentos y el mayor nivel socioeconómico se asociaron con HGNA. En el grupo total, el consumo de azúcares simples y grasas saturadas fue excesivo y el consumo de vitamina E y PUFAS estuvo por debajo del parámetro. Conclusiones: Se identificó HGNA en un tercio de los casos. Se demostró asociación entre HGNA y variables sociodemográficas. Ambos grupos tuvieron una ingesta aumentada de azúcares simples y disminuida de PUFAs. La ocurrencia selectiva de HGNA se podría relacionar con predisposición genética demostrada en población mexicana. Abstract: Introduction: Obesity is associated with nonalcoholic fatty liver disease (NAFLD) in children. Our aim was to analyze the association of dietary and sociodemographic factors with NAFLD in obese children and adolescents. Materials and methods: Thirty-three obese patients from 6-16 years of age were included in the present analytic cross-sectional study. Obesity was diagnosed with a body mass index z-score > 2 SD. NAFLD was estimated by liver ultrasound, serum amino transferases, and elastography. The sociodemographic variables were evaluated using validated questionnaires. Diet was estimated through two 24-hour recall dietary surveys focused on the quantity of food energy, simple sugars, polyunsaturated fatty acids (PUFAs), and antioxidants. Results: Hepatic steatosis was identified by abdominal ultrasound in 13 patients (39.4%) and the serum alanine aminotransferase level was above the upper reference value in 54.2%. A higher educational level in both parents, greater monthly food expenditure, and a higher socioeconomic level were associated with NAFLD. Overall, simple sugar and saturated fat consumption was above the recommended daily intake, whereas vitamin E and PUFA consumption was below those parameters. Conclusions: NAFLD was identified in one-third of the cases. There was an association between NAFLD and sociodemographic variables. Both groups had an increased intake of simple sugars and a reduced intake of PUFAs. The selective occurrence of NAFLD could be related to a genetic predisposition that has been demonstrated in a Mexican population.

Introduction: Obesity is associated with nonalcoholic fatty liver disease (NAFLD) in children. Our aim was to analyze the association of dietary and sociodemographic factors with NAFLD in obese children and adolescents. Materials and methods: Thirty-three obese patients from 6-16 years of age were included in the present analytic cross-sectional study. Obesity was diagnosed with a body mass index z-score > 2 SD. NAFLD was estimated by liver ultrasound, serum amino transferases, and elastography. The sociodemographic variables were evaluated using validated questionnaires. Diet was estimated through two 24-h recall dietary surveys focused on the quantity of food energy, simple sugars, polyunsaturated fatty acids (PUFAs), and antioxidants. Results: Hepatic steatosis was identified by abdominal ultrasound in 13 patients (39.4%) and the serum alanine aminotransferase level was above the upper reference value in 54.2%. A higher educational level in both parents, greater monthly food expenditure, and a higher socioeconomic level were associated with NAFLD. Overall, simple sugar and saturated fat consumption was above the recommended daily intake, whereas vitamin E and PUFA consumption was below those parameters. Conclusions: NAFLD was identified in one-third of the cases. There was an association between NAFLD and sociodemographic variables. Both groups had an increased intake of simple sugars and a reduced intake of PUFAs. The selective occurrence of NAFLD could be related to a genetic predisposition that has been demonstrated in a Mexican population. Resumen: Introducción y objetivo: La obesidad se asocia con el hígado graso no alcohólico (HGNA) en niños. El objetivo fue explorar la asociación de factores dietéticos y sociodemográficos con el HGNA en niños y adolescentes obesos. Material y métodos: Treinta y tres pacientes obesos de 6-16 años fueron incluidos en este estudio transversal analítico. El diagnóstico de obesidad se realizó con puntuación z del índice de masa corporal > 2 DE. El HGNA se estimó con ultrasonido hepático, aminotransferasas séricas y elastografía. Las variables sociodemográficas se evaluaron con cuestionarios validados. La dieta se estimó mediante dos encuestas dietéticas por recordatorio de 24 horas enfocadas a la cantidad de energía, azúcares simples, ácidos grasos poliinsaturados (PUFAS) y antioxidantes. Resultados: En 13 pacientes (39.4%) se identificó esteatosis hepática por ultrasonido abdominal; 54.2% tuvieron una concentración sérica de alanina aminotransferasa por arriba de la referencia. El nivel educativo superior de ambos padres, el mayor gasto familiar mensual en alimentos y el mayor nivel socioeconómico se asociaron con HGNA. En el grupo total, el consumo de azúcares simples y grasas saturadas fue excesivo y el consumo de vitamina E y PUFAS estuvo por debajo del parámetro. Conclusiones: Se identificó HGNA en un tercio de los casos. Se demostró asociación entre HGNA y variables sociodemográficas. Ambos grupos tuvieron una ingesta aumentada de azúcares simples y disminuida de PUFAs. La ocurrencia selectiva de HGNA se podría relacionar a predisposición genética demostrada en población mexicana.

Electrification has been a key component of technological progress and economic development since the industrial revolution. It has improved living conditions, spurred innovation, and increased efficiency across all sectors of our economy and all aspects of our lives. During the coming decades, electrification is expected to reach further and deeper into the transportation, building, and industry sectors, mainly motivated by the energy transition to a zero-carbonemission-based economy to mitigate climate change.

El artículo de datos presenta resultados preliminares de la encuesta Estilo de Vida en el contexto de la contingencia por COVID-19 en adultos-jóvenes veracruzanos, realizada en el mes de junio de 2020 como parte de la batería de instrumentos utilizada en el estudio “Ansiedad, depresión, estilos de vida y bienestar en el contexto sociocultural actual”. Los resultados de las variables presentadas dan cuenta de los estilos de vida reportados en de seis dimensiones: alimentación, actividad física, estado emocional, relaciones sociales, consumo de alcohol, tabaco y otras drogas, y cuidado en la salud, partiendo del supuesto de que el confinamiento social que se vive derivado de la contingencia por COVD-19 repercute de manera distinta ente los hombres y las mujeres. Se encontró que, de los 301 casos que respondieron la totalidad de la encuesta, 76% fueron mujeres y 24% hombres. Las mujeres reportaron un estilo de vida más saldable en su alimentación (consumo de futas y verduras diariamente, pocas bebidas con alto contenido de azúcar, por ejemplo), actividad física (practicar algún deporte, de bajo riesgo, menor frecuencia en el uso de redes sociales, televisión o videojuegos), un mejor estado emocional (control de sentimientos, confianza en el futuro y reconocimiento social), mejores relaciones sociales (apoyo familiar, relaciones favorables con amigos, compañeros), mayor interés por el cuidado de su salud física (chequeos médicos, medidas preventivas ante enfermedades), y mayor cuidado en la salud sexual y reproductiva (uso de métodos anticonceptivos, por ejemplo). Los varones por su parte, mostraron un estilo de vida más precario al reconocer mayor ingesta de alimentos “chatarra”, altamente azucarados, práctica de deportes más riesgosos (patineta, parkour -Trepar y saltar por muros haciendo acrobacias-, por ejemplo), mayor tiempo de exposición en redes sociales, televisión o videojuegos, percibir menor apoyo familiar y reconocimiento social, reportar mayor consumo de alcohol, tabaco y otras drogas (mariguana, cocaína, etc.); y estar expuestos ciertos riesgos de transmisión sexual o embarazos al tener más de una pareja sexual. Como puede apreciarse, si bien se parte del supuesto de que la calidad de vida se ha trastocado por el confinamiento ante la pandemia por COVID-19, se observan una serie de prácticas de cuidado de la salud en las mujeres en comparación con los varones, dejando entrever una serie de roles tradicionales de género, lo que lleva a la necesidad de analizar en estas características a mayor profundidad.

Introduction Our research was based on the BUS model, which provides guidelines for developing mobile applications for health. This model is supported by theories of behavior change, user-centered design, and social marketing. This study aimed to determine secondary school students' perceptions of a mobile application design for smoking prevention. Methods In 2018, qualitative research was conducted in three secondary schools located in the central part of the state of Veracruz, Mexico. Focus groups were established to explore beliefs about smoking and mobile phone use. The sketch technique was used to identify the characteristics for the mobile application. Results The students' perception of smoking allowed us to determine behaviors that can be changed: 1) associating cigarettes with a distraction from problems can be prevented; 2) peer and family pressure as a trigger to starting smoking can be avoided; and 3) tobacco use can be disassociated from being popular. Regarding the design of the mobile application prototype, an entertaining game with levels to help teenagers stay active was proposed. Conclusions Games for health can help modify user behavior and even positively influence their values. The final product was the prototype for the 'No le entres' (don't jump in) application. An important finding was that adolescents living in both urban and rural settings use mobile phones similarly.

Microgrids/nanogrids of prosumers must be able to adapt to new business opportunities related to energy trading. Therefore, highly accepted hierarchical control strategies should be modified to allow deliberate energy interchange among prosumers, even when the microgrid they are integrated in, operates islanded. This is the main contribution of this paper, as energy exchange between prosumers is rarely addressed when they are islanded from the main grid. This work proposes a comprehensive hierarchical control strategy for a multibus nanogrid of prosumers, each of them having photovoltaic generation, battery energy storage systems and loads, in such a way that different voltage and power setpoints for each prosumer allow such energy interchange. Power flow inside the nanogrid is controlled to guarantee the technical feasibility of the obtained setpoints. The proposed control strategy is defined and experimentally validated in both islanded and grid-connected modes, by means of a laboratory-scale prototype. In addition, a smooth transition between the two modes is demonstrated. An adequate capability of the power converters to follow setpoints is proved, with acceptable transient behavior.

Although there is a growing interest in developing fast charging methods to enhance the Electric Vehicles’ appeal, the main energy supply is still the single-phase outlet. While single-phase charging may be simpler than three-phase, there are challenges in the integration of the propulsion and charging systems without adding inductive grid filters. Such integration would bring benefits like the simplification and reduction of components, costs, volume or weight. This can be achieved by using the windings of the propulsion machine as grid filters, but the use of the electric motor as a grid inductive filter leads to the generation of pulsating torque during the charging state. This translates into vibration, noise and eventually, damage to the motor and other components of the system. In this work, the authors propose a control strategy that considerably reduces the peaks of pulsating torque generated in any rotor position while using the machine wingdings as filter. Simulation tests have been carried out to validate the control strategy, taking into account the system efficiency. Finally, experiments are conducted to prove that the reduction of the torque pulsation is achieved.

Urban foresters require methodologies that help to select tree species for urban environments, mainly in places where there is a large number of potential species such as the Valley of Mexico. We applied the Analytic Hierarchy Process (AHP) to select suitable native tree species that are under-represented or non-existent in Mexico City trees. Through bibliographic research, the selection criteria and the list of trees to be evaluated were selected; later, a group of specialists in urban forestry and arboriculture determined by pair-wise comparison matrices the specific weight of each selection criterion, while a set of taxonomists evaluated the rating of each attribute for each species. Finally, for practical purposes, the synthesis of both evaluations resulted in a ranking of 15 tree species according to their degree of aptitude suggested for Mexico City. According to results, Buddleja cordata, Quercus glaucoides and Litsea glaucescens obtained the highest degree of suitability as a large, medium and small-size species, respectively. The AHP proved to be an appropriate methodology to solve a complex problem through multiple criteria evaluation by diverse specialists in the subject. The implementation of the results contributes to the selection process of suitable tree species for urban environments.

En la actualidad, resulta cada vez más relevante estudiar el concepto de Bienestar desde una perspectiva multidimensional, que considere no sólo variables macrosociales, sino también aquellas inherentes a los individuos, como es el bienestar subjetivo. Desde el Observatorio de Calidad de Vida y Salud Social (OCVS), se ha aplicado una encuesta en línea con el objetivo de describir los niveles de bienestar subjetivo en población adulta del Estado de Veracruz en el contexto de la contingencia actual por COVID-19, con la finalidad de identificar las áreas de atención prioritarias para su intervención a corto y mediano plazo. Se realizó un estudio no experimental, ex post facto, con un muestreo por conveniencia, en el que se utilizó la escala Bienestar Subjetivo y Condiciones de Vida (BISCOV), participaron 485 personas, mayores de 18 años, radicadas en el estado de Veracruz, México. Se identificó una disminución en los niveles de bienestar subjetivo y las áreas que afectan dichas valoraciones, en comparación con lo observado en mediciones previas. Esto permite sentar una base empírica de las repercusiones que está permeando la pandemia por el COVID-19 en la vida cotidiana de los participantes en el estudio.

El objetivo del estudio fue comparar, entre estudiantes de bachillerato de Veracruz y Tamaulipas usuarios y no usuarios de drogas ilícitas, posibles diferencias en cuanto a la presencia de síntomas de ansiedad, control de impulsos, sintomatología depresiva, ideación e intento suicida. Se realizó un estudio no experimental, transversal, ex post facto, en el que participaron 806 estudiantes de preparatoria, 511 de Veracruz y 295 de Tamaulipas. Se conformaron cuatro grupos: los No usuarios 73.5% de Veracruz y 88.4% de Tamaulipas, y los grupos de Usuarios de drogas, 26.5% de Veracruz y 11.6% de Tamaulipas. Un porcentaje significativamente mayor de los Usuarios de drogas de ambos estados trabajan y estudian, presentan mayor impulsividad, más síntomas de depresión, ideación e intento suicida. Se puede concluir que los usuarios de drogas presentan mayor deterioro emocional, lo que permite contribuir al desarrollo de propuestas orientadas a incidir en los diferentes niveles de salud.

In cold and dense regions of the interstellar medium, such as molecular clouds, more than 200 gas-phase molecular species have been observed by means of infra-red and rotational spectroscopy techniques alongside solid sub-micrometer sized particles called dust grains. These grains are of uttermost importance because their surfaces serve as meeting points for chemical species that adsorb from the gas phase, diffuse and possibly react to form more complex molecules. These grains consist of a silicate or carbonaceous cores covered in layers of water dominated ices that contain other small volatile molecules such as CO, CO2, NH3, CH3OH. Most of the ice components originate from the adsorption and reaction of bare atoms, e.g., H, C, N and O, on the grain surfaces. An important challenge in Astrochemistry is to characterize the thermodynamics and kinetics of the main reaction steps of the bare atoms forming the ice components on the grain surfaces. As a first step previous to the reaction of these atomic species, in this paper we present results based on quantum chemistry methods on the adsorption of atomic carbon, nitrogen and oxygen on a crystalline water ice surface model mimicking the icy grain surfaces.