Numerical Simulation of Warm-air Drying of Mexican Softwood (Pinus pseudostrobus): An Empirical and Mechanistic Approach

In this work, the numerical simulation of Mexican softwood (Pinus pseudostrobus) drying is presented by solving a phenomenological model. The model was developed by considering the heat and mass balance in the representative elementary volume, which involves the solid, liquid and gas phases. We solved a system of partial differential equations by numerical factorization in COMSOL multiphysics 3.5a©. Three primary variables were solved: the moisture content, the temperature, and the dry-air mass. The numerical results were compared against both experimental data and a semi-empirical model (Characteristic Drying Curve) previously published. The warm-air drying of Mexican softwood was simulated on a one-dimensional basis by considering two experimental conditions: air flow temperature at 60 and 80 ºC. Relative humidity was not controlled in the tunnel dryer. Simulated drying kinetics showed good agreement with the experimental data

Association of cooking patterns with inflammatory and cardio-metabolic risk biomarkers

Diet has been clearly associated with cardiovascular disease, but few studies focus on the influence of cooking and food preservation methods on health. The aim of this study was to describe cooking and food preservation patterns, as well as to examine their association with inflammatory and cardio-metabolic biomarkers in the Spanish adult population. A cross-sectional study of 10, 010 individuals, representative of the Spanish population, aged 18 years or over was performed using data from the ENRICA study. Food consumption data were collected through a face-to-face dietary history. Cooking and food preservation patterns were identified by factor analysis with varimax rotation. Linear regression models adjusted for main confounders were built. Four cooking and food preservation patterns were identified. The Spanish traditional pattern (positively correlated with boiling and sautéing, brining, and light frying) tends to be cardio-metabolically beneficial (with a reduction in C-reactive protein (-7.69%)), except for high density lipoprotein cholesterol (HDL-c), insulin levels, and anthropometrics. The health-conscious pattern (negatively correlated with battering, frying, and stewing) tends to improve renal function (with a reduction in urine albumin (-9.60%) and the urine albumin/creatinine ratio (-4.82%)). The youth-style pattern (positively correlated with soft drinks and distilled alcoholic drinks and negatively with raw food consumption) tends to be associated with good cardio-metabolic health except, for lower HDL-c (-6.12%), higher insulin (+6.35%), and higher urine albumin (+27.8%) levels. The social business pattern (positively correlated with the consumption of fermented alcoholic drinks, food cured with salt or smoke, and cured cheese) tends to be detrimental for the lipid profile (except HDL-c), renal function (urine albumin +8.04%), diastolic blood pressure (+2.48%), and anthropometrics. Cooking and food preservation patterns showed a relationship with inflammatory and cardio-metabolic health biomarkers. The Spanish traditional pattern and the health-conscious pattern were associated with beneficial effects on health and should be promoted. The youth-style pattern calls attention to some concerns, and the social business pattern was the most detrimental one. These findings support the influence of cooking and preservation patterns on health

Zoogeografía de los gastrópodos terrestres del sur de Nuevo León, México

The terrestrial gastropods of the southern region of the state of Nuevo León were surveyed (december, 2001 – december, 2004). Samples were obtained from 35 localities, in differents vegetational types. The primary zoogeographical relationships are characterized by the presence of the endemics (34 species or subspecies: 40.48%, high value in northeastern México), those of neotropical and neartic affinities (27 species: 32.14%) and those exhibiting panamerican distributions (13 species: 15.48%). The three families with the largest number of endemic species (or subspecies) are the Spiraxidae and Urocoptidae (both with eight species), and the Humboldtianidae (five species). The vegetational types with the greatest biogeographical values are the gallery forest and pine forest. The highest values of malacofaunal similarities are between the submountain shrubs and savannah cultivation and also between the oak-pine forest and gallery forest.Se estudiaron (diciembre de 2001 a diciembre de 2004) los gastrópodos terrestres de la región sur del estado Nuevo León. Las muestras fueron obtenidas en 35 localidades, en diferentes tipos de vegetación. Las principales afinidades zoogeográficas son el endemismo de 34 especies o subespecies (40.48% de la malacofauna, valor alto en el noreste de México), la neotropical principalmente y neártica de 27 especies (32.14%) y la distribución panamericana de 13 especies (15.48%). Las familias con mayor número de especies o subespecies endémicas son Spiraxidae y Urocoptidae, ambas con ocho, y Humboldtianidae con cinco. Los mayores valores biogeográficos de la malacofauna terrestre se presentaron en la vegetación de galería y en el bosque de pino. Las mayores similitudes malacofaunísticas se observan entre el matorral submontano y el pastizal cultivado y entre el bosque de pino-encino y la vegetación de galería

ANÁLISIS ECOLÓGICO BÁSICO DE LOS GASTRÓPODOS TERRESTRES DE LA REGIÓN ORIENTAL DE SAN LUIS POTOSÍ, MÉXICO

Of 77 species of terrestrial gastropods found in the eastern region of the state of San Luis Potosí, the ecological conditions supporting the largest number of species of mollusks are as follows: oak forest (44 species), leaf litter and humus (66), soils which are humid throughout the year (53), 3000- 3500 mm annual rainfall (41) and 801-900 m altitude (43). Thysanophora hornii exhibits the greatest distribution with regard to vegetational types, humidity conditions, rainfall, soil types, and altitudinal ranges. The greatest values of diversity and evenness were obtained in the cloud forest (0.6895) and oak forest (0.3512) respectively. The chaparral exhibits the greatest dominance (0.9958) and habitat ecological width (0.3741). Mollusks communities were ecologically ranked lower than the tropical decidouos-subdeciduous forest. The highest qualitative similarity was observed between tropical deciduous-subdeciduous forest and savannah-cultivation (0.7462). The greatest quantitative similarity (0.3646) was observed between thorn forest and savannah-cultivation.En este estudio se caracterizaron las condiciones ecológicas en las que se presentaron 77 especies de gastrópodos terrestres en la región oriental de San Luis Potosí, existiendo más especies de moluscos en bosque de encino (44 especies), hojarasca y humus (66), suelos húmedos todo el año (53), precipitaciones de 3000-3500 mm anuales (41) y altitudes de 801-900 m (43). Thysanophora hornii es la de mas amplia distribución en función de los tipos de vegetación, condiciones de humedad, precipitación, tipos de suelo y rango de altitud. Los valores más grandes de diversidad y equitatividad se observaron en el bosque mesófilo de montaña (0.6895) y bosque de encino (0.3512). El mayor valor de dominancia (0.9958) y amplitud ecológica del hábitat (0.3471) se presentó en el matorral xerófilo. Las comunidades de gastrópodos terrestres se encontraron subordinadas ecológicamente a las del bosque tropical caducifolio – subcaducifolio, y a su vez ésta se halla subordinada a la del bosque de encino. El valor de similitud cualitativa más alto se observó entre el bosque tropical caducifolio-subcaducifolio y pastizal-cultivos (0.7462). Entre el bosque espinoso y pastizalcultivos se obtuvo el mayor valor de similitud cuantitativa (0.3646)

Parallel evolution of vgsc mutations at domains IS6, IIS6 and IIIS6 in pyrethroid resistant Aedes aegypti from Mexico

Aedes aegypti is the primary urban mosquito vector of viruses causing dengue, Zika and chikungunya fevers –for which vaccines and efective pharmaceuticals are still lacking. Current strategies to suppress arbovirus outbreaks include removal of larval-breeding sites and insecticide treatment of larval and adult populations. Insecticidal control of Ae. aegypti is challenging, due to a recent rapid global increase in knockdown-resistance (kdr) to pyrethroid insecticides. Widespread, heavy use of pyrethroid spacesprays has created an immense selection pressure for kdr, which is primarily under the control of the voltage-gated sodium channel gene (vgsc). To date, eleven replacements in vgsc have been discovered, published and shown to be associated with pyrethroid resistance to varying degrees. In Mexico, F1,534C and V1,016I have co-evolved in the last 16 years across Ae. aegypti populations. Recently, a novel replacement V410L was identifed in Brazil and its efect on vgsc was confrmed by electrophysiology. Herein, we screened V410L in 25 Ae. aegypti historical collections from Mexico, the frst heterozygote appeared in 2002 and frequencies have increased in the last 16 years alongside V1,016I and F1,534C. Knowledge of the specifc vgsc replacements and their interaction to confer resistance is essential to predict and to develop strategies for resistance management

Catalytic conversion of 5-hydroxymethylfurfural (5-HMF) over Pd-Ru/FAU zeolite catalysts.

We present this study on FAU-type zeolites were prepared varying the Si/Al ratio (4, 5 and 6) and crystallization time (4, 6 and 8 h) to produce a highly pure and homogeneous material with enhanced surface area values. Bimetallic Pd-Ru and Pt-Ru (0.5 wt.% of each metal) were impregnated onto the zeolites matrix by the incipient wetness impregnation method. The materials were characterized by X-ray diffraction (XRD), nitrogen physisorption, Fourier Transform Infrared spectroscopy (FT-IR), Scattering Electronic Microscopy (SEM), Scattering and Transmission Microscopy (STEM), temperature-programmed desorption (TPD), temperature-programmed desorption (TPR) and Inductively Couples Plasma- Mass Spectrometer (ICP-MS). Results indicated that using lower Si/Al ratios favored the catalytic activity. Also, the longest crystallization time had a positive effect on surface area, homogeneous particle size distribution and crystallinity. The catalytic performance in the esterification of 5-hydroxymethylfurfural (5-HMF) to produce 5-acetoxymethylfurfural (AcMF) was investigated. The maximum 5-HMF conversion of 87.28 % was achieved using pure zeolite with relation Si/Al = 5, and 8 h of crystallization. Pd-Ru supported onto same zeolite showed a conversion of 84.22 %. The highest selectivity towards AcMF of 71.29 % with pure zeolite Si/Al = 5 and 8 h of crystallization was achieved, followed by Pd-Ru/FAU with Si/Al = 5 and 8 h of crystallization, achieving 60.42 %. Finally, results shown that the interaction between the properties of zeolitic support and the metallic species, specifically Pd, had a positive effect in the catalytic process the pristine zeolite showed improved catalytic characteristics related to its acid strength

Confianza y redes sociales en productores de hortalizas en San Luis Potosí, México

In this study, there were two objectives: a) analyzing the social networks of vegetable producers in the middle zone of San Luis Potosí, México, in order to determine their organization; and b) establishing the importance that trust has for business relations such as loaning money, asking for money or setting up a society. Surveys were applied to 35 producers, who referenced 170 names that were later concentrated into 39 producers. With the field information, symmetrical matrices were built to schematize the network structure, and three logistic regression models were formulated to establish the probability of intention for action based on trust. The results show the importance that proximity between actors has. It is concluded that different levels of trust explain the disposition to lending money, setting up a society and, to a lesser degree, asking for money on loan.En la presente investigación se tuvieron dos objetivos: a) analizar las redes sociales de los productores de hortalizas de la zona media de San Luis Potosí, México, a fin de determinar su organización; y b) establecer la importancia que tiene la confianza para las relaciones de negocios como prestar dinero, pedir dinero o hacer una sociedad. Se encuestó a 35 productores, que referenciaron 170 nombres que posteriormente se concentraron en 39 productores. Con la información de campo se construyeron matrices simétricas para esquematizar la estructura de la red y se formularon tres modelos de regresión logística para establecer la probabilidad de la intención de acción basada en la confianza. Los resultados muestran la importancia que tiene la proximidad entre actores. Se concluye que diferentes niveles de confianza explican la disposición a prestar dinero, hacer una sociedad y, en menor medida, a pedir dinero prestado

Oxidative Damage in Lymphocytes of Copper Smelter Workers Correlated to Higher Levels of Excreted Arsenic

Arsenic has been associated with multiple harmful effects at the cellular level. Indirectly these defects could be related to impairment of the integrity of the immune system, in particular in lymphoid population. To characterize the effect of Arsenic on redox status on this population, copper smelter workers and arsenic unexposed donors were recruited for this study. We analyzed urine samples and lymphocyte enriched fractions from donors to determinate arsenic levels and lymphocyte proliferation. Moreover, we studied the presence of oxidative markers MDA, vitamin E and SOD activity in donor plasma. Here we demonstrated that in human beings exposed to high arsenic concentrations, lymphocyte MDA and arsenic urinary levels showed a positive correlation with SOD activity, and a negative correlation with vitamin E serum levels. Strikingly, lymphocytes from the arsenic exposed population respond to a polyclonal stimulator, phytohemaglutinin, with higher rates of thymidine incorporation than lymphocytes of a control population. As well, similar in vitro responses to arsenic were observed using a T cell line. Our results suggest that chronic human exposure to arsenic induces oxidative damage in lymphocytes and could be considered more relevant than evaluation of T cell surveillance

The Vertical Reference System in the Argentine Republic

This paper is a summary of the tasks that have been developed and the ones that are under development in the Argentine Republic by means of joint activities, agreements and cooperation among institutions, together with national and international scientific and educational agencies, related to: -Completion, calculation, unification and link to planialtimetric networks. -Gravity activities and procedures used for heights correction. -Linking to neighboring countries networks. -Initial leveling experiences by means of GPS technology, and results obtained. -Regional and national geoid modeling. -Determination of vertical crustal movements, evaluation of sea technology, variations of the mean sea level and its influence over the zero of the argentine height system.Facultad de Ciencias Astronómicas y Geofísica

Active commuting to and from university, obesity and metabolic syndrome among Colombian university students

Background: There is limited evidence concerning how active commuting (AC) is associated with health benefits in young. The aim of the study was to analyze the relationship between AC to and from campus (walking) and obesity and metabolic syndrome (MetS) in a sample of Colombian university students. Methods: A total of 784 university students (78.6% women, mean age = 20.1 ± 2.6 years old) participated in the study. The exposure variable was categorized into AC (active walker to campus) and non-AC (non/infrequent active walker to campus: car, motorcycle, or bus) to and from the university on a typical day. MetS was defined in accordance with the updated harmonized criteria of the International Diabetes Federation criteria. Results: The overall prevalence of MetS was 8.7%, and it was higher in non-AC than AC to campus. The percentage of AC was 65.3%. The commuting distances in this AC from/to university were 83.1%, 13.4% and 3.5% for < 2 km, 2- 5 km and > 5 km, respectively. Multiple logistic regressions for predicting unhealthy profile showed that male walking commuters had a lower probability of having obesity [OR = 0.45 (CI 95% 0.25–0.93)], high blood pressure [OR = 0.26 (CI 95% 0.13–0.55)] and low HDL cholesterol [OR = 0.29 (CI 95% 0.14–0.59)] than did passive commuters. Conclusions: Our results suggest that in young adulthood, a key life-stage for the development of obesity and MetS, AC could be associated with and increasing of daily physical activity levels, thereby promoting better cardiometabolic health.This study was part of the project entitled “Body Adiposity Index and Biomarkers of Endothelial and Cardiovascular Health in Adults”, which was funded by Centre for Studies on Measurement of Physical Activity, School of Medicine and Health Sciences, Universidad del Rosario (Code N° FIUR DNBG001) and Universidad de Boyacá (Code N° RECT 60)