The role of gas infall in the evolution of disc galaxies

Spiral galaxies are thought to acquire their gas through a protracted infall phase resulting in the inside-out growth of their associated discs. For field spirals, this infall occurs in the lower density environments of the cosmic web. The overall infall rate, as well as the galactocentric radius at which this infall is incorporated into the star-forming disc, plays a pivotal role in shaping the characteristics observed today. Indeed, characterising the functional form of this spatio-temporal infall in-situ is exceedingly difficult, and one is forced to constrain these forms using the present day state of galaxies with model or simulation predictions. We present the infall rates used as input to a grid of chemical evolution models spanning the mass spectrum of discs observed today. We provide a systematic comparison with alternate analytical infall schemes in the literature, including a first comparison with cosmological simulations. Identifying the degeneracies associated with the adopted infall rate prescriptions in galaxy models is an important step in the development of a consistent picture of disc galaxy formation and evolution.Comment: 12 pages, 12 figures, MNRAS, accepte

Propuesta de mediación comunitaria para la integración social desde la perspectiva de la Planeación Territorial: Caso de la Colonia Santa Teresa, Huehuetoca, Estado de México.

En México se cuenta con una base legal relativa a la mediación, sin embargo, dichas leyes aún no se implementan de la manera adecuada, ya que deja a un lado alternativas de solución para las problemáticas que se presentan en las zonas urbanas, en donde día con día las sociedades enfrentan controversias que no son atendidas de manera pertinente y por expertos. Por tanto, cuando surgen conflictos solo se implementan soluciones momentáneas al no estar constituida la mediación como una solución efectiva y de control, la causa del conflicto no se atiende, solo se remedia de manera parcial, situaciones que experimenta el municipio de Huehuetoca, Estado de México.El derecho a vivir en una ciudad segura es un principio básico de las sociedades urbanas. Actualmente se observa de manera significativa la aparición de conjuntos habitacionales propiciando con ello la llegada de migrantes, donde las distintas culturas y formas de convivencia han generado espacios inseguros y de conflicto social. La vulnerabilidad de estas zonas por una parte y por otra, la existencia de focos de violencia, donde la delincuencia hacia las personas y bienes en el espacio público se han vuelto cotidiano; demanda de las sociedades territorios de convivencia pacífica

The role of gas infall in the evolution of disc galaxies

Spiral galaxies are thought to acquire their gas through a protracted infall phase resulting in the inside-out growth of their associated discs. For field spirals, this infall occurs in the lower density environments of the cosmic web. The overall infall rate, as well as the galactocentric radius at which this infall is incorporated into the star-forming disc, plays a pivotal role in shaping the characteristics observed today. Indeed, characterising the functional form of this spatio-temporal infall in-situ is exceedingly difficult, and one is forced to constrain these forms using the present day state of galaxies with model or simulation predictions. We present the infall rates used as input to a grid of chemical evolution models spanning the mass spectrum of discs observed today. We provide a systematic comparison with alternate analytical infall schemes in the literature, including a first comparison with cosmological simulations. Identifying the degeneracies associated with the adopted infall rate prescriptions in galaxy models is an important step in the development of a consistent picture of disc galaxy formation and evolution

Lockdown due to COVID-19 in Spanish Children Up to 6 Years: Consequences on Diet, Lifestyle, Screen Viewing, and Sleep

Objectives: To record how the habits of children under 6 years of age in Cadiz have changed during lockdown, in order to identify those that could be a handicap for the problem of overweight and obesity.Methods: We developed a new questionnaire to analyse family living habits. The questionnaire was administered online to parents of children aged zero-six years. Eating habits, sedentary lifestyles, screen viewing, and sleep changes were evaluated.Results: Changes were found in family living habits, as shown by the results of McNemar's tests (p-value < 0.01 in all pairs except one, p-value = 0.097). A worsening of habits was also found to be more accentuated in families with low income, low educational level or small size of home. Some positive aspects associated with family meals and parental involvement were found.Conclusions: The lockdown has showed a significant break in the main routines of the children that could affect their health and may add to the worsening of the already poor childhood obesity situation. The positive aspects found can be instrumental in improving the situation in future similar situations

Densidad de los residuos sólidos de tres instituciones educativas de la ciudad de Chachapoyas, departamento de Amazonas - 2017

La presente investigación tuvo como objetivo determinar la densidad de los residuos sólidos generados en las instituciones educativas San Juan de la Libertad, Virgen Asunta y Seminario Jesús María de la ciudad de Chachapoyas. La metodología consistió en recolectar los residuos sólidos por espacio de cinco días consecutivos en los niveles educativos primario y secundario, el pesaje y segregación se realizó en el centro de acopio, a partir de ello se determinó los siguientes parámetros, densidad, generación per cápita, composición física y humedad de los residuos sólidos. Aplicándose una encuesta para identificar hábitos de consumo en los grupos humanos estudiados (docentes, estudiantes y personal administrativo), para determinar el número de muestras se utilizó la fórmula de muestreo estratificado por afijación proporcional ya que la densidad de los residuos sólidos está relacionada con los estilos de vida y costumbres de las personas. Como resultado del estudio de los residuos sólidos se obtuvo que en la I.E. San Juan de la Libertad la densidad es 57.395 kg/m3, generación per cápita 0.030 kg y humedad 82.2% mientras que en la I.E. Virgen Asunta la densidad es 52.141 kg/ m3, generación per cápita 0.037 kg/ hab./día y humedad 78.72% y en la I.E. Seminario Jesús María la densidad es 54.243 kg/m3, la generación per cápita 0.049 kg/hab./día y humedad 75.06%. El tipo de residuos sólidos que más generan en las tres I.E. son residuos orgánicos. Los resultados de la encuesta nos dan a conocer que el 63.1% de la I.E. San Juan de la Libertad traen alimentos desde sus casas a la I.E., el tipo de alimentos que más traen son frutas con un 50.2% y lo que más compran dentro de su I.E. son galletas con un 34.4%, en la I.E. Virgen Asunta el 78.4% traen alimentos desde sus casas a la I.E., el tipo de alimentos que más traen son frutas con 56.1% y lo que más compran en su I.E. es comida con un 49.6%. Asimismo, en la I.E. Seminario Jesús María el 39.5% traen alimentos desde su casa a la I.E., el tipo de alimentos que traen son frutas con un 39.5% y lo que más compran en la I.E. son comida con un 64%

Effects of food-related health concerns and risk perception on the consumption frequency of fresh vegetables

Consuming fresh vegetables certainly brings health benefits; however, these types of products may also contain biological, chemical and technological elements that can affect people´s health due to lack of food safety. We developed a conceptual model to explain the main relationships between food-related health concerns (FHCs) and risk perceptions (RPs) on consumption frequency of fresh vegetables (CFFV) from a food safety point of view. We applied a structured questionnaire to 1028 consumers in the Central and South Central zones of Chile, where the main agricultural production of the country is concentrated. Through a structural equation model, we determined the moderator effect of RP on the relationship between FHC and CFFV. As a result, CFFV is less if RP is present in the minds of the consumer, impacting the direct effect of FHC on CFFV. Finally, our results suggest that reducing risks associated with the production and commercialization of fresh vegetables can improve health concerns related to food and the consumption of fresh vegetables. Therefore, the state must improve surveillance systems of fresh vegetables commercialized in local markets.Consuming fresh vegetables certainly brings health benefits; however, these types of products may also contain biological, chemical and technological elements that can affect people´s health due to lack of food safety. We developed a conceptual model to explain the main relationships between food-related health concerns (FHCs) and risk perceptions (RPs) on consumption frequency of fresh vegetables (CFFV) from a food safety point of view. We applied a structured questionnaire to 1028 consumers in the Central and South Central zones of Chile, where the main agricultural production of the country is concentrated. Through a structural equation model, we determined the moderator effect of RP on the relationship between FHC and CFFV. As a result, CFFV is less if RP is present in the minds of the consumer, impacting the direct effect of FHC on CFFV. Finally, our results suggest that reducing risks associated with the production and commercialization of fresh vegetables can improve health concerns related to food and the consumption of fresh vegetables. Therefore, the state must improve surveillance systems of fresh vegetables commercialized in local markets

El rol del género sobre el efecto moderador de una etiqueta de inocuidad alimentaria entre la calidad y riesgo percibido en vegetales frescos

The role of food safety label in fresh vegetables has received little attention in developing economies and less attention from the perspective of gender. In this context, a conceptual model was developed to explain the effect of food safety label as a moderator variable of risk perception and quality perceived for fresh vegetables from the perspective of gender. A structural equation model was developed in central and south central Chile, using a convenience sample (n = 1114) of vegetables buyers. The main finding of the study was that for females, the food safety label moderated the effect of risk perception on perceived quality; while for males this effect was not significant. However, given that females are primarily responsible for purchasing food, food safety labels are a tool for consumers to recognize unsafe vegetables; at the same time, it can influence the purchase decision of those consumers worried by certain risks associated with fresh vegetables.El rol de la etiqueta de inocuidad alimentaria en hortalizas frescas ha recibido poca atención en economías en desarrollo y menos atención desde la perspectiva del género. En este contexto, se desarrolló un modelo conceptual para explicar el efecto de la etiqueta de inocuidad alimentaria como una variable moderadora de la percepción de riesgo y la calidad percibida para hortalizas frescas desde la perspectiva del género. Se desarrolló un modelo de ecuaciones estructurales en el centro y sur de Chile central, utilizando una muestra por conveniencia (n = 1114) de compradores de hortalizas. El principal hallazgo del estudio fue que para las mujeres la etiqueta de inocuidad alimentaria moderó el efecto de la percepción de riesgo sobre la calidad percibida; mientras que para los hombres este efecto no fue significativo. Sin embargo, dado que las mujeres son las principales responsables de la compra de alimentos, las etiquetas de inocuidad alimentaria son una herramienta para que estos consumidores reconozcan las hortalizas riesgosas; al mismo tiempo, puede influir en la decisión de compra de aquellos consumidores preocupados por ciertos riesgos asociados con las hortalizas frescas.Fil: Adasme-Berríos, Cristian. Universidad Católica del Maule (Talca, Chile)Fil: Sánchez, Mercedes. Universidad Pública de Navarra (Pamplona, España)Fil: Mora, Marcos. Universidad de Chile. Facultad de Ciencias Agronómicas.Fil: Díaz, José. Universidad de TalcaFil: Schnettler, Berta. Universidad de La Frontera (Chile)Fil: Lobos, Germán. Universidad de Talc

The gender role on moderator effect of food safety label between perceived quality and risk on fresh vegetables

The role of food safety label in fresh vegetables has received little attention in developing economies and less attention from the perspective of gender. In this context, a conceptual model was developed to explain the effect of food safety label as a moderator variable of risk perception and quality perceived for fresh vegetables from the perspective of gender. A structural equation model was developed in central and south central Chile, using a convenience sample (n = 1114) of vegetables buyers. The main finding of the study was that for females, the food safety label moderated the effect of risk perception on perceived quality; while for males this effect was not significant. However, given that females are primarily responsible for purchasing food, food safety labels are a tool for consumers to recognize unsafe vegetables; at the same time, it can influence the purchase decision of those consumers worried by certain risks associated with fresh vegetables.The role of food safety label in fresh vegetables has received little attention in developing economies and less attention from the perspective of gender. In this context, a conceptual model was developed to explain the effect of food safety label as a moderator variable of risk perception and quality perceived for fresh vegetables from the perspective of gender. A structural equation model was developed in central and south central Chile, using a convenience sample (n = 1114) of vegetables buyers. The main finding of the study was that for females, the food safety label moderated the effect of risk perception on perceived quality; while for males this effect was not significant. However, given that females are primarily responsible for purchasing food, food safety labels are a tool for consumers to recognize unsafe vegetables; at the same time, it can influence the purchase decision of those consumers worried by certain risks associated with fresh vegetables

Motivación laboral en trabajadores Part time y Full time de un supermercado de Chimbote, 2020

El presente estudio tuvo como objetivo determinar los niveles de Motivación laboral en trabajadores part time y full time de un supermercado de Chimbote, 2020, correspondió a una investigación de tipo básica, observacional, de nivel descriptivo y diseño no experimental. La muestra estuvo conformada por 132 trabajadores, que laboran en la modalidad de tiempo completo y tiempo parcial de un supermercado; así mismo, para la recolección de datos se utilizó la encuesta y como instrumento la escala de motivación de Steers y Braunstein (1976), adaptada al Perú por Palma (2000) y Ventura (2018); consta de 3 factores, que son motivación de logro, poder y afiliación. Dentro de los resultados se observa, según la prueba U de Mann-Whitney, un p-valor de 0,044 menor que 0,05; aceptándose la hipótesis alternativa, estableciéndose que existe diferencias en la motivación laboral, entre los trabajadores full time y part time; siendo los trabajadores full time quienes presentan un mejor rango promedio de motivación; asimismo, se encontraron resultados similares en las dimensiones de motivación de poder, logro y afiliación en los trabajadores de un supermercado de Chimbote