203 research outputs found

    Potential natural vegetation and pre-anthropic pollen records on the Azores Islands in a Macaronesian context

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    This paper discusses the concept of potential natural vegetation (PNV) in the light of the pollen records available to date for the Macaronesian biogeographical region, with emphasis on the Azores Islands. The classical debate on the convenience or not of the PNV concept has been recently revived in the Canary Islands, where pollen records of pre-anthropic vegetation seemed to strongly disagree with the existing PNV reconstructions. Contrastingly, more recent PNV model outputs from the Azores Islands show outstanding parallelisms with pre-anthropic pollen records, at least in qualitative terms. We suggest the development of more detailed quantitative studies to compare these methodologies as an opportunity for improving the performance of both. PNV modelling may benefit by incorporating empirical data on past vegetation useful for calibration and validation purposes, whereas palynology may improve past reconstructions by minimizing interpretative biases linked to differential pollen production, dispersal and preservation.Spanish Ministry of Economy and Competititvity, project PaleoNAO [CGL2010-15767]Spanish Ministry of Economy and Competititvity, project RapidNAO [CGL2013-40608-R]Spanish Ministry of Economy and Competititvity, project PaleoMODES [CGL2016-75281-C2-1-R]info:eu-repo/semantics/publishedVersio

    Leptin and its Association with Obesity among Mexican Adolescents

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    Purpose: To investigate the association between leptin concentrations and nutritional status among a Mexican adolescent population. Methods: Cross-sectional study with 448 adolescents attending five schools in Durango, Mexico. Serum leptin concentrations were measured by ELISA. Other measurements included height, weight, and waist and hip circumference. Body fat of participants was assessed with bio-electrical impedance using a body composition analyzer InBody-720. Sociodemographic information was also collected. Results: Based on IOTF BMI cut-off points, 34.1% of adolescents were overweight and obese and prevalence rates were higher among females (37.1%) than males (29.5%). In agreement with waist circumference, 22.5% of participants were overweight and had abdominal obesity; and based on waist-to-hip ratio 35.5% had truncal obesity. Leptin concentration levels among females (19.33 ng/dL) were two times higher than among males (40.07 ng/dL) with a statistical significant difference (p=0.000). Leptin levels among obese females (69.92 ng/dL) were three times higher than among underweight females (17.70 ng/dL). Conversely, leptin levels among males (43.52 ng/dL) were four times higher than among their underweight counterparts (10.08 ng/dL). Mean leptin levels among women with body fat greater than 28% (46.44 ng/dL) were statistically different and 1.7 times higher than those with lower body fat (25.96 ng/dL) (p=0.000). Mean leptin levels among males with body fat greater than 20% (30.17 ng/dL) were statistically different (p=0.000) and 2.4 times higher than among males with lower body fat (12.35 ng/dL). Among both females and males, leptin concentration levels were positively and significantly associated with visceral body fat (R2=0.344 females; R2=0.373 males; p=0.000). Conclusions: Significant correlations between leptin and BMI, body fat percentage, and visceral adipose tissue area indicate that this hormone can be used as a biomarker for obesity among adolescents

    Relationship between Dyslipidemia and Physical Activity in Mexican Children

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    Purpose: The purpose of this research was to determine the relationship between physical activity and lipid levels in children 10 to 13 years of age living in Durango, Mexico. Method: Cross-sectional study performed in 823 children (n=428, 52% boys; n=395, 48% girls) enrolled in nine elementary schools. Physical activity was monitored in two ways: a) a questionnaire was used to obtain information about physical activity done in the previous week, and b) steps were counted for 24 hours with a Yamax SW-200 pedometer. A subsample of 425 children provided serum samples to determine total-cholesterol (TC), HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C) and triglycerides (TG). Results: Over half (52.9%) participated in a sports team inside or outside of school; most (90.9%) reported one sport, with few (9.1%) reporting 2-3 sports. The most commonly reported vigorous PA was: soccer (33%), basketball (24%), jogging (8-12 km/h) (23%), volleyball (17%) and others (3%). Those who participated in a sports team had higher levels of HDL-C and lower TG. Participation in 2 or 3 sports reduced TG levels just over 20%. Boys who reported 30 minutes or more per day of vigorous activity had lower triglyceride levels than those who reported less (p = 0.020). Boys accumulated significantly more steps per day (m=17,030 ± 6444) than girls (m=12,991± 5316; p \u3c 0.001). The prevalence of lipid abnormalities was higher in children with fewer steps. Hypercholesterolemia was lower in boys with the highest number of steps (p = 0.044), in girls the differences were not statistically significant. Hypertriglyceridemia in both sexes was lower in the group with the highest number of steps (

    Production Response and Digestive Enzymatic Activity of the Pacific White Shrimp Litopenaeus vannamei (Boone, 1931) Intensively Pregrown in Microbial Heterotrophic and Autotrophic-Based Systems

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    Shrimp postlarvae were reared into different microcosm systems without water exchange; a traditional system based on simple fertilization to improve microalgae concentration (control), an autotrophic system (AS) based on the promotion of biofloc and biofilm by the addition of fertilizer and artificial substrates and a heterotrophic system (HS) based on the promotion of heterotrophic bacteria by the addition of nitrogenous and carbonaceous sources and artificial substrates. Better growth performance and survival were registered in shrimp from the AS and HS compared to the control. Feed conversion ratios were below 0.7 for all treatments, but AS and HS were significantly lower than the control. Regarding digestive performance, no significant differences were observed for trypsin, amylase and lipase activities among AS and control shrimp; however, shrimp from HS showed a higher trypsin and amylase activities, suggesting a higher digestive activity caused by the presence of microbial bioflocs. The presence of biofilm and bioflocs composed by either autotrophic or heterotrophic organisms in combination with formulated feed improved the growth performance and survival of shrimp. Apparently, such combination fits the nutritional requirements of shrimp

    Relationship Between Dyslipidemia and Obesity in Children

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    Purpose: Dyslipidemia is a general term that refers to abnormal levels of lipids. The purpose of this research was to determine the relationship among the nutritional state and the percentage of body fat with the levels of lipids in 10 to 13 year old children living in the city of Durango, Mexico. Method: The study was carried out with 823 elementary school children. The selection was done at random. The biochemical studies were done in a subpopulation of 425 children. Each child underwent the following studies: sociodemographic, anthropometric and corporal composition. After fasting overnight, a venous blood sample was obtained. lipid profile including cholesterol, LDL-C, HDL-C and triglycerides were determined in serum. In order to classify lipid levels we used the reference values suggested by the National Cholesterol Education Program (NCEP). The desirable values were: TC \u3c170 mg\u3e/dl, HDL -C \u3e45 mg/dl, LDL -C \u3c110 mg\u3e/dl and TG \u3c100 mg\u3e/dl. The nutritional state was calculated according the age and sex specific BMI values developed by the CDC. Fat mass content was determined using a bioelectrical impedance analyzer (Tanita TBF-215). Statistical analyses were performed using SPSS14. Results: This study included 428 (52%) boys and 395 (48%) girls. Mean age was 11.5 years. The prevalence of overweight and obesity was 36.7. In the population studied we found abnormal levels of lipids in: cholesterol (41.8%), HDL-C (55.8%), LDL-C (32.3%) and TG (38.5%). The girls showed lower levels of HDL-C than the boys (p \u3c 0.05), the other lipoproteins were not statistical different ( p \u3e 0.05). The lipids levels (TC, LDL-C and TG) were higher in those with a BMI greater than 85 th percentile of BMI, and DHL-C was lower. In those with a body fat greater than 20%, all the lipids levels resulted abnormal. Conclusions: A high risk of dislypidemia was associated with gender, BMI and body fat

    Proyecto para el estadio municipal César Angulo de la ciudad de El Tránsito, departamento de San Miguel

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    Elaborar una propuesta arquitectónica del Estadio César Angulo en la ciudad de El Tránsito departamento de San Miguel, que cuente con la infraestructura adecuada, que cumpla con las necesidades físico espacial, idóneo para el espectador y el deportista. En el proceso de la investigación se tomarán diferentes métodos los cuales nos llevarán a realizarla de una forma objetiva y sistemática, dando inicio en los aspectos generales hasta llegar a los aspectos específicos. proyecto para el estadio municipal César Angulo de la ciudad de El Transito, departamento de San Miguel. Se dividirá en cinco fases, para luego obtener el diseño arquitectónico final. Las fases son las siguientes: FASE I. Conceptualización del problema FASE II. Marco Referencial, FASE III. Diagnóstico, FASE IV. Pronóstico, FASE V. Propuesta de diseño. Es necesario brindarle a la juventud y a la población en general instalaciones para la práctica de actividades deportivas y recreativas que contribuyan a mejorar su salud física y mental. La investigación se realizó utilizando una metodología sistemática; el cual se desarrolló en las siguientes fases: conceptualización o generalidades, marco referencial, diagnóstico, pronóstico, obteniendo como resultado la propuesta de diseño arquitectónico más idónea. Se estableció una solución arquitectónica para las instalaciones del estadio municipal en la que se puede integrar al lugar, generando espacios funcionales y formalmente adaptados a las necesidades del proyecto, aplicando conceptos y teorías de diseños

    TRPV4 Channels Promote Pathological, but Not Physiological, Cardiac Remodeling through the Activation of Calcineurin/NFAT and TRPC6

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    TRPV4 channels, which respond to mechanical activation by permeating Ca2+ into the cell, may play a pivotal role in cardiac remodeling during cardiac overload. Our study aimed to investigate TRPV4 involvement in pathological and physiological remodeling through Ca2+-dependent signaling. TRPV4 expression was assessed in heart failure (HF) models, induced by isoproterenol infusion or transverse aortic constriction, and in exercise-induced adaptive remodeling models. The impact of genetic TRPV4 inhibition on HF was studied by echocardiography, histology, gene and protein analysis, arrhythmia inducibility, Ca2+ dynamics, calcineurin (CN) activity, and NFAT nuclear translocation. TRPV4 expression exclusively increased in HF models, strongly correlating with fibrosis. Isoproterenol-administered transgenic TRPV4-/- mice did not exhibit HF features. Cardiac fibroblasts (CFb) from TRPV4+/+ animals, compared to TRPV4-/-, displayed significant TRPV4 overexpression, elevated Ca2+ influx, and enhanced CN/NFATc3 pathway activation. TRPC6 expression paralleled that of TRPV4 in all models, with no increase in TRPV4-/- mice. In cultured CFb, the activation of TRPV4 by GSK1016790A increased TRPC6 expression, which led to enhanced CN/NFATc3 activation through synergistic action of both channels. In conclusion, TRPV4 channels contribute to pathological remodeling by promoting fibrosis and inducing TRPC6 upregulation through the activation of Ca2+-dependent CN/NFATc3 signaling. These results pose TRPV4 as a primary mediator of the pathological response

    Dise?o de un plan de negocios para una empresa de servicios de estancia y club de d?a para adultos mayores en los NSE B y C en Lima Metropolitana

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    En el presente trabajo, se busca determinar la viabilidad comercial, operativa y econ?mica, as? como las estrategias para la implementaci?n del servicio de Estancia y Club de D?a para adultos mayores en los NSE B y C. El Servicio del Club operar? en un local de 1,600mts, su infraestructura estar? dise?ada seg?n las condiciones f?sicas de los adultos mayores; en donde se realizar?n diversas actividades f?sicas, l?dicas y mentales, en un ambiente divertido a fin de mantener al m?ximo sus facultades durante el proceso de envejecimiento. Pensando en aquellos adultos mayores que requieren de asistencia en sus actividades diarias, pero deseoso de socializar, se ha pensado en el servicio de ?Estancia? que adem?s de los anteriormente descritos se brindar? el servicio de cuidado no medico asistido por enfermeras
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