46 research outputs found
Estimating the geographical distribution of the prevalence of the metabolic syndrome in young Mexicans
The geographical distribution of the metabolic syndrome (MetS) prevalence in young Mexicans (aged 17-24 years)
was estimated stepwise starting from its prevalence based on the body mass index (BMI) in a study of 3,176 undergraduate
students of this age group from Mexico City. To estimate the number of people with MetS by state, we multiplied its prevalence derived from the BMI range found in the Mexico City sample by the BMI proportions (range and state) obtained from the Mexico 2006 national survey on health and nutrition. Finally, to estimate the total number of young people with MetS in Mexico, its prevalence by state was multiplied by the share of young population in each state according to the National Population and Housing Census 2010. Based on these figures, we estimated the national prevalence of MetS at 15.8%, the average BMI at 24.1 (standard deviation = 4.2), and the prevalence of overweight people (BMI ≥25) of that age group at 39.0%. These results imply that 2,588,414 young Mexicans suffered from MetS in 2010. The Yucatan peninsula in the south and the Sonora state in the north showed the highest rates of MetS prevalence. The calculation of the MetS prevalence by
BMI range in a sample of the population, and extrapolating it using the BMI proportions by range of the total population, was found to be a useful approach. We conclude that the BMI is a valuable public health tool to estimate MetS prevalence in the whole country, including its geographical distribution
Broadening the antibacterial spectrum of histidine kinase autophosphorylation inhibitors via the use of epsilon-poly-L-lysine capped mesoporous silica-based nanoparticles
[EN] Two-component systems (TCS) regulate diverse processes such as virulence, stress responses, metabolism and antibiotic resistance in bacteria but are absent in humans, making them promising targets for novel antibacterials. By incorporating recently described TCS histidine kinase autophosphorylation inhibitors (HKAIs) into epsilon-poly-L-lysine capped nanoparticles (NPs) we could overcome the Gram negative (Gr(-)) permeability barrier for the HKAIs. The observed bactericidal activity against Gr(-) bacteria was shown to be due to the enhanced delivery and internalization of the HKAIs and not an inhibitory or synergistic effect of the NPs. The NPs had no adverse effects on mammalian cell viability or the immune function of macrophages in vitro and showed no signs of toxicity to zebrafish larvae in vivo. These results show that HKAIs are promising antibacterials for both Gr(-) and Gr + pathogens and that NPs are a safe drug delivery technology that can enhance the selectivity and efficacy of HKAIs against bacteria. (C) 2016 Elsevier Inc. All rights reserved.This work was funded by FP7 ITN STARS-Scientific Training in Antimicrobial Research Strategies (Contract No. PITN-GA-2009-238490, J.M.W., A.M.), H2020 MSCA IF (AND-659121, N.V.), grant BIO2013-42619-P from the Ministerio de Economia y Competitividad (A.M.), grant from the Spanish Government (Project MAT2015-64139-C4-1-R,N. M., J.R.M, R.M.M.), and a grant from Generalitat Valenciana (Project PROMETEOII/2014/047, N.M.). and Prometeo II/2014/029, A.M.).Velikova, N.; Mas Font, N.; Miguel-Romero, L.; Polo, L.; Stolte, E.; Zaccaria, E.; Cao, R.... (2017). Broadening the antibacterial spectrum of histidine kinase autophosphorylation inhibitors via the use of epsilon-poly-L-lysine capped mesoporous silica-based nanoparticles. Nanomedicine Nanotechnology Biology and Medicine. 13(2):569-581. https://doi.org/10.1016/j.nano.2016.09.011S56958113
Recent Chicano poetry = Neueste Chicano-Lyrik. - Zweisprachig: Englisch / Deutsch
Die legalen und illegalen Einwanderer aus Mexiko haben in den USA in Malerei, Musik, Film und Literatur eine eigene Kultur entwickelt, die im Spannungsfeld zwischen mexikanischen Traditionen und der politisch-sozialen Realität in den Vereinigten Staaten angesiedelt ist. Im vorliegenden Band werden die verschiedenen lyrischen Tendenzen innerhalb dieser wahrhaft inter-amerikanischen Bewegung dokumentiert
Una nueva estrategia para la enseñanza de cursos avanzados de fĂsica experimental: modelo rotativo
A novel strategy for teaching advanced experimental Physics is presented. The strategy is based on a “rotating” model that take advantage of the different facilities, the equipment, as well as the human resources available for teaching the courses. The model strengthens the collaboration between teachers and researches, and also allows a bigger number of
students attending in each group of the courses. Because of its structure, the model is transferable to other experimental disciplines and even, to other educational level. It has been implemented since two years ago in the School of Sciences of the National Autonomous University of Mexico for the 4th year courses of “Laboratory of Contemporary Physics I” and “Laboratory of Contemporary Physics II” of the Physics undergraduate program. The model is presented, as well as the results obtained since its implementation.Se presenta una estrategia colaborativa para la enseñanza de cursos avanzados de fĂsica experimental a travĂ©s de la implementaciĂłn de un modelo de carácter “rotativo” que fortalece la enseñanza de este tipo de cursos. El modelo se basa en el aprovechamiento de la infraestructura existente en los diferentes centros e institutos de investigaciĂłn
involucrados con la licenciatura de FĂsica. Entre otras ventajas, el modelo permite el incremento del nĂşmero de estudiantes que pueden atender a estos cursos, además de incentivar y consolidar la colaboraciĂłn entre acadĂ©micos e investigadores docentes participantes. Por su estructura, resulta transferible a otras disciplinas de carácter experimental e incluso, a otros niveles educativos. Se presentan los avances y resultados obtenidos durante dos años de implementaciĂłn de esta estrategia de enseñanza en las asignaturas de “Laboratorio de FĂsica Contemporánea I” y “Laboratorio de FĂsica Contemporánea II” del octavo y noveno semestre, respectivamente, del plan de estudios de la Licenciatura en FĂsica de la Universidad Nacional AutĂłnoma de MĂ©xico
Characterization of trophic links in an agrosystem : weed seed predation by carabid beetles
L’agroécologie offre de nouvelles perspectives à l’agriculture et ainsi une voie vers une gestion alternative des adventices à travers différents mécanismes écosystémiques de régulation. La prédation des graines est l’un d’entre eux et son étude fait depuis peu l’objet de recherches visant à approfondir les connaissances relatives à ce processus. Ce travail de thèse cherche (i) à caractériser la prédation des graines d’adventices, les principaux prédateurs Carabidæ et la ressource en graines disponible à l’échelle locale dans une culture courante (blé d’hiver); (ii) à étudier précisément les profils de prédation des principaux prédateurs et les interactions entre les composantes biologiques impliquées; (iii) à introduire des éléments de réponse relatifs au potentiel de régulation des communautés d’adventices via la prédation des graines par les Carabidæ. Des approches complémentaires ont été utilisées afin de répondre à ces problématiques : un suivi à long terme de terrain, des tests de préférences en laboratoire, une simulation des taux de prédation à long terme à partir des données ponctuelles ainsi qu’une étude à grande échelle des prédateurs et du stock de graines.L’étude des variations spatio-temporelles de la prédation via un dispositif de terrain durant la période d’activité des prédateurs a mis en évidence trois pics de prédation dont un seul correspond au pic de prédateurs (avant la moisson). La ressource en graines disponible au sol est quant à elle présente majoritairement lors du premier et du dernier pic de prédation, et aucune augmentation de ressource n’a été observée après moisson. Ces dynamiques semblent stables, restant valables indépendamment de l’échelle spatiale (intra ou interchamp) et des espèces carabiques et adventices étudiées.Toutes les espèces adventices ne font pas l’objet de la même intensité de prédation, et de manière générale, les graines de petites tailles ont été préférentiellement prédatées, au champ comme en test de cafétéria au laboratoire. Cependant, les espèces carabiques semblent avoir des profils de prédation différents entre guildes trophiques, ainsi qu’au sein d’une même guilde. De ce fait, la prise en compte des préférences de consommation dans l’étude des relations prédation-prédateurs tout comme la combinaison des données prédateurs et graines disponibles permet parfois d’améliorer les corrélations, notamment pour les espèces les plus prédatées.Une simulation de la prédation annuelle suggère des pertes en graines dues à la prédation non négligeables, pouvant atteindre pour l’espèce la plus prédatée, ici Viola arvensis, jusqu’à près de 80% des graines disponibles. En parallèle, une étude à grande échelle de l’évolution du stock de graines montre une corrélation négative entre prédateurs et évolution de la banque de graines, suggérant une régulation de la banque de graines via les prédateurs carabiques.L’ensemble de ces résultats suggère que prendre en compte la diversité fonctionnelle des communautés de prédateurs et d’adventices est un point important dans la compréhension de la prédation compte tenu des préférences de consommation des prédateurs et des dynamiques temporelles des différents acteurs.Agroecology gives evidence of new perspectives in agriculture, and open doors for alternative weed management approaches through different regulation mechanisms. Seed predation is one of them, and the interest is growing to deepen knowledge, relative to this process. This Phd work aims (i) to describe weed seed predation, the dominant carabid predators and the available resource at a local scale in a common crop (winter wheat); (ii) to study predation profiles of main predators, and the pair-wise correlations between the biological components of the system; (iii) to bring new insights regarding potential regulation of weed communities, through seed predation by carabid beetles. Complementary approaches have been used to tackle these aspects: a long-term field study, some cafeteria tests, a simulation of annual predation rates from point-to-point estimates, as well as a large-scale field study of predators and seed resource. Study of spatio-temporal variations of predation, via field experiment during the main activity period of carabids, has shown a three-peak pattern, one of them corresponding to predators’ peak, just before harvest. Weed resource available on soil surface is high in the first and last peaks of predation, and no increase of resource has been observed after harvest. These dynamics are independent of the spatial scale (intra or inter-field) and carabid species. The different weed species do not show the same levels of predation, and, as a whole, small-seeded species are more eaten, in both lab and field conditions. However, carabids have different preferences among trophic guilds, but also within a same guild. Therefore, in order to study predation, it is essential to combine predators and seed data, as well as considering preferences of predators. A simulation of annual seed predation shows important rates of seed loss, reaching up to 80% for the most predated species, V.arvensis. A large scale study of seed bank shows a negative correlation between predators’ activity density and seed bank change, assuming that there is a seed bank regulation by carabid predators. All together, these results show that functional diversity of predators’ and weeds’ communities is a key factor in understanding predation
Ecuaciones antropométricas para el cálculo de grasa corporal en adultos jóvenes
Dado que para la población Latinoamericana se cuenta con escasas ecuaciones antropométricas validadas para determinar porcentaje de masa grasa (% MG), se diseñaron ecuaciones antropométricas prácticas para calcular el % MG en adultos jóvenes. Se realizaron mediciones antropométricas por técnicas validadas, y se calculó el % MG por densitometría (BodPod) y biompedancia. Se reclutaron 284 voluntarios (18-35 años), de uno y otro sexo. Las ecuaciones se diseñaron por regresión lineal múltiple por el método de todas las regresiones posibles y se validaron por su grado de bondad de ajuste (R2), error estándar de estimación (EEE) y por validación cruzada. En hombres: % MG por densitométría R2 = 0.78, EEE = 3.64 %, p < 0.001; % MG por bioimpedancia R2 = 0.76, EEE = 2.48 %, p < 0.001. En mujeres: % MG por densitométría R2 = 0.98, EEE = 4.02%, p < 0.001; % MG por bioimpedancia R2= 0.99, EEE = 2.37 %, p < 0.001. Las ecuaciones aquí diseñadas presentan sencillez, alta validez y confiabilidad, siendo útiles en la clínica y campo deportivo.Given that in Latin America we have few validated anthropometric equations to determine percentage of fat mass (% MG), practical anthropometric equations were designed to calculate the % MG in young adults. Anthropometric measurements were made by validated techniques, and % MG was calculated by densitometry (BodPod) and bioimpedance. We recruited 284 volunteers (18-35 years), men and women. The equations were designed by multiple linear regression by the method of all possible regressions, and validated by their degree of goodness of fit (R2), standard error of estimation (SES), and cross-validation. In men: % MG by densitometry R2 = 0.78, SES = 3.64%, p <0.001; % MG by bioimpedance R2 = 0.76, SES = 2.48%, p <0.001. In women: % MG by densitometry R2 = 0.98, SES = 4.02 %, p <0.001; % MG by bioimpedance R2 = 0.99, SES = 2.37 %, p <0.001. The equations here designed have simplicity, high validity, and reliability, being useful in the clinic and sports field
Una aplicaciĂłn de la transformada de Laplace en el estudio de la calidad del agua
<p>En el contexto acadĂ©mico, la transformada de Laplace es un mĂ©todo propio de un curso de ecuaciones diferenciales que puede ser utilizado dentro del ámbito ambiental para calcular el comportamiento de la concentraciĂłn de oxĂgeno disuelto (OD) en un rĂo, en rĂ©gimen estacionario, tomando en consideraciĂłn la respiraciĂłn microbiana (DBO) y la reaireaciĂłn. La finalidad real de este trabajo es que sirva como herramienta en los cursos de calidad del agua. La problemática a tratar fue observada bajo el principio de conservaciĂłn de la materia, por medio del cual se obtuvo una ecuaciĂłn diferencial parcial que modelo el OD, dicha ecuaciĂłn fue resuelta al aplicar el mĂ©todo de la transformada de Laplace. Los resultados demuestran el clásico comportamiento del OD y su demanda biolĂłgica en sistemas naturales. Se identificaron una zona de descomposiciĂłn, una zona sĂ©ptica (con la más baja concentraciĂłn de OD) y una zona de recuperaciĂłn. Podemos concluir que la transformada de Laplace es un mĂ©todo sencillo y eficaz en el estudio de la calidad del agua en efluentes naturales.</p>