Desarrollo de un Sistema de Cría Artificial para Anastrepha fraterculus (Wied.) (Diptera: Tephritidae)

A methodological process is described here to solve two bottle necks that render the establishment of fruit flies under artificial conditions for mass production difficult. The first was the selection of an oviposition system and the second the adaptation to the artificial diet used for larval development. Females preferred to oviposit on yellow spheres, and on white organza cloth flat panels covered with transparent silicon. A larval diet used to rear A.ludens, allowed the highest larval development, survival from egg to larva was 26.9%, larval weight 19.6mg, pupation at 24 h 97.7%, pupal weight 16.7mg and adult emergence 83.3%. Survival curves (nx, 1x) and life expectancy (ex) indicated at least 50% of the adults survive ~40 days. Life expectancy was of 34.74 days. The reproductive rate was 345.38 daughters/mother/generation; the intrinsic rate of population growth was 0.35days-1; while the median generation time and the time of duplication were 16.82 and 20.2 days, respectively. Moreover, we discuss results based on quality control parameters of insects after of 16 generations in mass-rearing under artificial conditions. Se describe el proceso metodológico para solucionar dos cuellos de botella que dificultan el establecimiento de la cría artificial de Anastrepha fraterculus a gran escala. Primero, la selección del sistema de oviposición y segundo la adaptación a la dieta artificial utilizada para el desarrollo larvario. Las hembras tuvieron una mayor preferencia para ovipositar en esferas de color amarillo y en paneles planos elaborados con tela tipo organza de color blanco cubiertos con una película de silicón transparente. Después de evaluar las dietas para el desarrollo larvario de cinco especies de moscas de la fruta, la dieta con la que se obtuvieron los rendimientos más altos correspondió a la dieta ALU (Anastrephaludens), con la cual la supervivencia de huevo a larva fue del 26.9%, peso de larva de 19.6 mg, porcentaje de pupación a las 24 h 97.7%, peso de pupa 16.7 mg y emergencia de adultos de 83.3%. El análisis de las curvas de supervivencia (nx, lx) y la estimación de la expectativa de vida (ex) indicaron que al menos el 50% de los individuos vivieron ~40 días. La expectativa de vida del adulto al momento de la emergencia fue de 38.74 días. La tasa neta de reproducción fue de 345.38 hijas/madre/generación, la tasa intrínseca de crecimiento poblacional fue de 0.35 días-1; mientras que el tiempo medio de generación y el tiempo de duplicación de la población fue de 16.82 y de 20.2 días, respectivamente. Asimismo, se discuten valores de los parámetros de calidad registrados en los insectos luego de 16 generaciones bajocondiciones de cría artificial.

Weight-loss practices among university students in Mexico

To evaluate the prevalence of weight-loss practices among university students from Tlaxcala, Mexico. A cross-sectional study of 2,651 university students was conducted. Logistic regression tests were used to estimate the probability of students trying to lose weight and successfully achieving weight loss. Nearly 40% of students attempted to lose weight, though only about 7% lost more than 10% of their body weight and maintained this weight loss during the time of the study. The methods used most were exercise and dieting, and those who dieted were more successful at losing weight. The high prevalence of weight-loss attempts and the poor outcomes with these weight-loss methods among this sample of university students is a public health concern. Universities should provide students with healthy weight-control approaches, which include offering information about healthier lifestyles, access to healthy food and opportunities to be physically active

The correlation between cognitive styles and written corrective feedback preferences among Iranian and Turkish EFL learners

This study aimed at finding the correlation between Iranian and Turkish EFL learners’ cognitive styles and their preferences for different WCF types. Sixty out of seventy-five EFL students at the intermediate level in two contexts (Iran and Turkey) were selected through the Oxford Placement Test. There were two instruments in this research: The Learning Styles Questionnaire, and CF questionnaire. The researcher gave detailed instructions on how to complete the surveys. The findings demonstrated that there was a correlation between EFL students’ cognitive styles and their WCF preferences in both Iran and Turkey contexts. The second research question results indicated that there was a relationship between learners’ cognitive styles and their preferences for different types of errors to be corrected. The results of the third research question showed that the correlation between Iranian students’ cognitive styles and their preferences for different CF frequencies was not significant. The last research question results showed that the correlation between Turkish students’ cognitive styles and their preferences for different CF frequencies was not significant

Analysis of press around the frame rate sociopolitical hydric

El encuadre sociopolítico ha sido un instrumento de análisis en torno a la influencia de los medios de comunicación sobre la opinión pública. La difusión del tandeo y los subsidios asociados a la gestión desregulada del Estado, es analizada en el presente estudio para esclarecer la influencia de los medios impresos en la salud pública y el Desarrollo Local. Se realizó un estudio retrospectivo de corte cualitativo con la técnica de análisis de contenido en la que se llevó a cabo una selección no probabilística de 103 notas de prensa considerando el periodo que va de enero del año 2000 a diciembre del año 2012. Los resultados muestran que el encuadre socioeconómico es superior al encuadre sociopolítico identificado como preponderante en la literatura. En referencia a los estudios del estado del conocimiento, las implicaciones de ambos encuadres para la democratización de la administración de los servicios hídricos, la percepción de salud pública ambiental y el Desarrollo Local Sustentable fueron discutidas.The sociopolitical setting has been an instrument of analysis on the influence of media on public opinion. The spread of tandem and subsidies associated with deregulated state management is analyzed in the present study to clarify the influence of print media in public health and local development. A retrospective study with qualitative content analysis technique in which conducted a nonrandom selection of 103 press releases considering the period from January 2000 to December 2012 cut was made. Results show that socioeconomic and sociopolitical frame exceeds the frame identified as predominant in the literature. Referring to the studies of the state of knowledge, the implications of both frames for the democratization of the management of water services, the perception of environmental public health and Local Sustainable Development were discussed

Anchoring of urban renewal: Urban complex Paseo Molino in the Historic Center of the city of Toluca, Mexico

Currently in the historical centers of the Mexican cities converge modernizing tendencies expressed in their physical form, commercial activities and social tensions. The article analyzes the anchoring of urban renewal in the historic center of the city of Toluca, through the Paseo Molino complex, which marks a milestone in the production of vertical housing, shops and services in a sector that does not know similar backgrounds. Through semi-structured interviews and exploratory tours, the urban environment of the project, the agents and mechanisms of the appropriation of urban land and the prospective of the expected impacts are characterized. The urban anchor expresses levels of intervention and degrees of public and private decision that configure a different mode of urban management through the intensification of urban use and mechanisms that establish the trust to guarantee profitability. It concludes in the importance of the rearrangement of government and private sector relations to face the continuity of the past that goes back almost two centuries, and which will henceforth constitute a factor that could curb the multiplication of modern urban interventions in the historic center of the city of Toluca.Actualmente en los centros históricos de las ciudades mexicanas convergen tendencias modernizantes expresadas en su forma física, actividades comerciales y tensiones sociales. El artículo analiza el anclaje de la renovación urbana en el centro histórico de la ciudad de Toluca, a través del conjunto Paseo Molino, el cual marca un hito en la producción de vivienda vertical, comercios y servicios en un sector que desconoce antecedentes semejantes. Por medio de entrevistas semiestructuradas y recorridos exploratorios, se caracteriza el entorno urbano del proyecto, los agentes y mecanismos de la apropiación del suelo urbano y la prospectiva de los impactos esperados. El anclaje urbano expresa niveles de intervención y grados de decisión pública y privada que configuran un modo distinto de gestión urbana a través de la intensificación del uso urbano y mecanismos que instituyen el fideicomiso para garantizar la rentabilidad. Se concluye en la importancia del reacomodo de las relaciones gobierno y sector privado para enfrentar la continuidad del pasado que se remonta a casi dos siglos, y que en lo sucesivo constituirá un factor que podría frenar la multiplicación de modernas intervenciones urbanísticas en el centro histórico de la ciudad de Toluca.Universidad Autónoma del Estado de México Consejo Nacional de Ciencia y Tecnologí

Factorial design for preparing chitosan nanoparticles and its use for loading and controlled release of indole-3-acetic acid with effect on hydroponic lettuce crops

The excessive use of agrochemicals generates damage to the environment, so their controlled release from biodegradable nanoparticles represents a good solution. In this study, chitosan nanoparticles (CNPs) were prepared by ionic gelation with sodium tripolyphosphate (TPP), according to a 24 factorial design to evaluate the effect of different factors (chitosan amount, TPP amount, agitation speed, and agitation time) influencing the nanoparticle size (NPS) and the polydispersity index (PDI). Once established the proper conditions by the factorial design, CNPs were prepared and loaded with indole-3-acetic acid (CNP-IAA). The nanoparticles loaded with chitosan:IAA mass ratio equal to 1:0.25, showed the higher loading capacity, thus were then used for the release tests and hydroponic lettuces crops. The analysis by dynamic light scattering (DLS) reveals a mean diameter for CNPs and CNP-IAA of ~149 and ~183 nm, respectively. Moreover, further characterization by thermogravimetric analysis, Fourier transform infrared spectroscopy and scanning electron microscopy, indicates that nanoparticles were effectively loaded with IAA. In addition, the release assays results were adjusted to the Korsmeyers-Peppas mathematical model, showing that 100% of the hormone is released in about 48 h. Also, the model fitting suggests that the release process is carried out in two steps: the first of releasing by diffusion followed by a second of sustained-release. Accordingly, our results prove that CNPs-IAA applied to the hydroponic crop of the Crocantela variety crisp lettuce (Latuca sativa L.), have a beneficial effect on the plant growth producing an increase of 30.9% in the number of lettuce leaves

Capacidad de dos especies vegetativas en la acumulación de metales pesados

Habitat fragmentation allows for vegetative species to be used as indicators of environmental pollution by heavy metals. Considering the distribution of Prosopis laevigata (mesquite) and Schinus molle (pepper tree) heavy metal concentrations were determined as potential indicators of environmental impact assessment for agricultural and livestock, rural settlement, commercial and service, urban settlement and mining land uses. A total of 30 sampling points were established during summer, autumn, winter and spring, based on the presence of the two species. Applying the technique of ICP-MS, concentrations of Al, As, Co, Cu, Cd, Pb, Ti, V and Zn were determined. With a statistic model the interactions between species, type of land use and season with respect to the concentration of these minerals in the leaf material were determined. Results indicated that the presence of heavy metals is determined by the effect of the species, land use and season, and the possible association between these. The specie of mesquite was the most efficient for bioaccumulation of Pb, Co and Al. In the same way, the pepper tree was more efficient with respect to Ti. On one hand, trees located in the mining land use showed the highest concentrations of Cu, Zn, Cd, Pb, Co and As. On the other hand, the spring season presented the highest concentration of Cu, Zn, Co, Ti and V. With that, it could be demonstrated that As, Co, Cd, Pb, Ti and Zn concentrations were above the normal limit. Therefore, the dynamics and functionality, environmental factors and physiological differences to develop physicalchemical processes in the absorption and transport of these elements towards the leaves are a determining factor of vegetative species placed under conditions of fragmentation, are good elements for surveying on pollution and environmental impact.La fragmentación del hábitat permite aprovechar especies vegetativas como indicadoras de contaminación ambiental por metales pesados. Considerando la distribución de Prosopis laevigata (mezquite) y Schinus molle (pirul) se determinaron las concentraciones de metales pesados en material foliar para evaluar el impacto ambiental de los usos de suelo agropecuario, residencial rural, comercial y servicio, residencial urbano y minero. Fueron establecidos 30 puntos de muestro durante las estaciones de verano, otoño, invierno y primavera, basados en la presencia de las dos especies. Aplicando la Técnica ICP-MS fueron determinadas las concentraciones de Al, As, Co, Cu, Cd, Pb, Ti, V y Zn. Con un ANOVA se probaron las interacciones entre especie, tipo de uso de suelo y estación con respecto a la concentración de estos minerales en material foliar. Los resultados indicaron que la presencia de metales pesados está condicionada por el efecto de la especie, uso de suelo y la estación, así como la posible asociación entre estos. El mezquite resultó ser más eficiente en la bioacumulación de Pb, Co y Al. En el caso del pirul solo fue más eficiente con respecto al Ti. Los árboles ubicados en el uso de suelo minero obtuvieron las mayores concentraciones de Cu, Zn, Cd, Pb, Co y As. Por otra parte, la estación de primavera incidió en la mayor concentración de Cu, Co, Ti y V. Con esto se pudo demostrar que As, Co, Cd, Pb Ti y Zn presentaron concentraciones arriba del límite normal en material foliar. Por lo tanto, la dinámica y funcionalidad, factores ambientales y diferencias fisiológicas para desarrollar procesos físico-químicos en la absorción y transporte de estos elementos hacia las hojas son un factor determinante de las especies vegetativas situadas bajo condición de fragmentación, lo que contribuye ser un buen elemento de estudio de la contaminación y evaluación del impacto ambiental.Fil: Alcalá Jáuregui, Jorge. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Rodríguez Ortíz, Juan C.. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Hernández Montoya, Alejandra. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Filippini, María Flavia. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Martínez Carretero, Eduardo. Instituto Argentino de Investigaciones de las Zonas Áridas Fil: Diaz Flores, Paola Elizabeth. Universidad Autónoma de San Luis Potosí. Facultad de Agronomí

Bromatological composition of arboreal-shrub plants consumed in one season by goats in the Mixteca Poblana, Mexico

The tree-shrub vegetation consumed by goats was studied in three family-operated units of caprine production in the municipality of Piaxtla of the Mixteca Poblana in Mexico, during the rainy season (June to November 2004). The natural mountainous foraging land in question is composed of low, thorny deciduous forest, xerophytic vegetation, secondary tree-shrub vegetation, and small areas of oak trees and grassland. The climate is warm sub-humid with rain in summer (350 to 800 mm annual total) and semi-arid and hot in the dry season (23ºC annual mean temperature). Animal preference for the different plants and their parts was determined by observing the number of bites/h received and nutritional value by chemical analysis of vegetative material sampled between 8:30 and 12.00 h. Forty tree-shrub type plants were identified of which the following six species were the most consumed: Haemotoxylum brasiletto, Acacia bilimerkii var., A. pennatula, Pithecellobium acatlense, P. dulce, and Amelanchir denticulada. The percentage distribution of the plant parts consumed was: leaf, flower and fruit, 35; leaf, flower and pod, 23; flower and pod, 14; leaf and pod, 10; pod and bark, 8; bark, 5; and flower, 5. In percentage chemical composition the most favorable were P. dulce (leaf and pod) and A. dnticulada (leaf) with contents of PB, NDF and ADF of 18.3. 35.3, and 25.1; 13.1, 30.9, and 17.7, respectively, while A. bilimekii var. (leaf) was poorest with corresponding values of 14.4, 50.3, and 39.6