2,953 research outputs found
Fitness and health-related quality of life dimensions in community-dwelling middle aged and older adults
<p>Abstract</p> <p>Background</p> <p>The aim of the present study was to identify the physical fitness (PF) tests of a multi-component battery more related to the perception of problems in each dimension of the health-related quality of life (HRQoL) assessed by the EuroQol 5 dimensions 3 level questionnaire (EQ-5D-3L) in community-dwelling middle-aged and older adults</p> <p>Methods</p> <p>A cross-sectional study was conducted with 7104 participants (6243 females and 861 males aged 50-99 years) who were recruited in the framework of the Exercise Looks After You Program, which is a public health program designed to promote physical activity (PA) in community-dwelling middle-aged and older adults. Participants were assessed by the EQ-5D-3L questionnaire and a battery of fitness tests. The responses to each EQ-5D-3L dimension were collapsed into a two-tier variable consisting of «perceive problems» and «do not perceive problems». Correlation coefficients for the relationships between the HRQoL variables, between the PF variables, and between the HRQoL and PF variables were obtained. Two logistic regression models, one adjusted and one unadjusted, were developed for each EQ-5D-3L dimension.</p> <p>Results</p> <p>There were significant correlations between all variables except anxiety/depression and the back scratch test. The PF tests that correlated best with the HRQoL dimensions were the Timed Up-and-Go Test (TUG) and the 6-min walk; pain/discomfort and anxiety/depression correlated less well. All PF tests correlated, especially the TUG and 6-min walk tests. Unadjusted logistic models showed significant goodness of fit for the mobility and pain/discomfort dimensions only. Adjusted logistic models showed significant goodness of fit for all dimensions when the following potential confounding variables were included: age, gender, weekly level of PA, smoking and alcohol habits, body mass index, and educational level. For all dimensions, the highest odds ratios for the association with PF tests were with the TUG; this was observed with both the unadjusted and adjusted models.</p> <p>Conclusions</p> <p>The perception of problems, as measured by the EQ-5D-3L dimensions, was associated with a lower level of fitness, particularly for those dimensions that relate more closely to physical components. The PF tests that associated most closely with the perception of problems in the HRQoL dimensions were the TUG and the 6-min walk. This information will aid the design and assessment of PA programs that aim to improve HRQoL.</p
Anatomy of corpus callosum in prenatally malnourished rats
Indexación: Web of Science; ScieloThe effect of prenatal malnutrition on the anatomy of the corpus callosum was assessed in adult rats (45-52 days old). In the prenatally malnourished animals we observed a significant reduction of the corpus callosum total area, partial areas, and perimeter, as compared with normal animals. In addition, the splenium of corpus callosum (posterior fifth) showed a significant decrease of fiber diameters in the myelinated fibers without changing density. There was also a significant decrease in diameter and a significant increase in density of unmyelinated fibers. Measurements of perimeter's fractal dimensions from sagittal sections of the brain and corpus callosum did not show significant differences between malnourished and control animals. These findings indicate that cortico-cortical connections are vulnerable to the prenatal malnutrition, and suggest this may affect interhemispheric conduction velocity, particulary in visual connections (splenium).http://ref.scielo.org/nph4s
Producción de materia seca y componentes morfológicos de cuatro cultivares de Brachiaria en el trópico
El objetivo fue evaluar bajo condiciones de temporal la adaptación de cuatro cultivares de Brachiaria, con base en su comportamiento agronómico a diferentes edades de corte. Las variables medidas fueron: altura, producción de hojas, tallos, total, material vivo y muerto. Los datos se analizaron en diseño de bloques al azar con arreglo en parcelas divididas y prueba de Tukey, P<0.05, para diferencia múltiple de medias. La altura fue mayor (P<0.001) en los cultivares B. brizantha (Mg4) e Híbrido Mulato, con 42 y 41 cm, respectivamente, con relación a B. brizantha. La producción de hoja y material vivo fue mayor en el Híbrido Mulato, con 688 kg ms ha-1 (P<0.006) y 1,104 ms ha-1; P<0.001), respectivamente, comparada con B. decumbens. La producción de tallos (457 kg ms ha-1; P=0.05) y materia seca total (1,125 ms ha-1; P=0.05), tuvo tendencia a ser mayor en Híbrido Mulato. Se concluye que los cultivares con mejor desempeño agronómico fueron Brachiaria ruziziensis X B. brizantha (Híbrido Mulato) y Mg4, sin diferencia en la producción de materia seca entre cultivares
Ranking de las aptitudes emocionales de los ingenieros comerciales requeridas por las empresas medianas y grandes del sector manufacturero de la ciudad de Talca.
116 p."El capital humano es el recurso mas importante en una empresa exitosa", pero no lo veamos como una frase hecha, sino seamos consecuentes con ella. La correcta aplicación de este discurso ayudara a los ejecutivos a contratar a las mejores personas para sus empresas. En este estudio se determinaron las aptitudes que proponen los autores citados en forma pertinente, siendo todas estas de carácter nacional, como son, nombradas en forma general: Conocer y manejar los propios estados internos; Comprender las tendencias que nos guían o facilitan la obtención de las metas; Captar sentimientos, necesidades e intereses ajenos e; Inducir en otros las repuestas deseadas. Todas estas aptitudes hoy en día son esenciales para ser contratado en una empresa cualquiera, con esto queremos decir que la pericia técnica o el titulo profesional se da por hecho, pero lo que es poseer algunas de estas aptitudes emocionales es un requisito que cada vez mas necesario para permanecer en un trabajo interesante y que nos satisfaga. Por ende la importancia de poseer personal dotado de inteligencia emocional para el futuro de las organizaciones,)independiente del rubro estudiado, es fundamental dado lo competitivo y globalizado de los mercados, pues ya no solo se compite con productos de calidad sino con el buen use de la gente. Según estas aptitudes, el estudio determine cuales eran los requerimientos de las empresas manufactureras de la ciudad de Talca (grandes y medianas) en los ingenieros comerciales y estas organizaciones, a través de una encuesta pudieron establecer el orden de importancia para ellos a la hora de contratarlos. Finalmente se pudo lograr el objetivo final y general del estudio, que fue poder establecer un ranking con respecto a las aptitudes emocionales relevantes para los encargados de contratar al personal y establecer el primer estudio que trata de darle importancia al tema, con el fin de generar análisis posteriores a otros sectores de la economía, además de crear conciencia de la relevancia que esta teniendo esta teoría
IDENTIFICACIÓN, USOS Y MEDICIÓN DE LEGUMINOSAS ARBÓREAS FORRAJERAS EN RANCHOS GANADEROS DEL SUR DEL ESTADO DE MÉXICO
El objetivo del trabajo fue identificar las especies arbóreas leguminosas, usos, densidad, frecuencia, abundancia y medidas dasométricas en ranchos ganaderos del sur del Estado de México; así como evaluar la producción de follaje (kg materia seca árbol-1ha-1) de Pithecellobium dulce, Haematoxylum brasiletto y Gliricidia sepium -preferidas por los ganaderos como fuente de forraje y con mayor densidad-; y evaluar la producción de fruto (kg materia seca árbol-1ha-1) de Acacia cochliacantha y P. dulce. La información de usos se obtuvo mediante entrevistas semiestructuradas aplicadas a 69 ganaderos, cantidad que representó 83% de la población. Las mediciones de los árboles se realizaron en seis ranchos mediante trabajo de campo. La información se analizó usando estadísticas descriptivas. Se identificaron 12 especies arbóreas (Acacia cochliacantha, Lysiloma divaricata, Pithecellobium dulce, Haematoxylum brasiletto y Gliricidia sepium), las cuales presentaron mayor densidad, frecuencia y abundancia. De 46.6% de las arbóreas, su follaje y fruto es consumido por rumiantes; de 20%, es consumido follaje, fruto y flor. Se proporcionan de cinco a ocho usos en 80% de las especies, además del forrajero, como leña, poste, sombra, cerca viva, medicinal, consumo humano, artesanal y maderable. Las arbóreas con mayor fuste fueron: Caesalpinia coriaria, Pithecellobium dulce, Enterolobium cyclocarpum y Leucaena esculenta, con diámetro basal (DB) de 47.11 a 57.2 cm, diámetro a la altura del pecho (DAP) de 49.34 a 50.3 cm y altura (A) de 7.4 a 14.5 m, los cuales son preferidos para sombra. La producción de follaje de Pithecellobium dulce, Haematoxylum brasiletto y Gliricidia sepium fue de 44.5, 8.8 y 8.4 kg MS arbol-1, respectivamente. La producción de fruto de Pithecellobium dulce y Acacia cochliacantha fue 63.9 y 21.7 kg MS árbol-1, respectivamente. Las 12 leguminosas arbóreas identificadas en la zona son reconocidas por los productores como arbóreas multipropósito, cuyo follaje es fuente de alimento para el ganado en lluvias y el fruto en secas, por lo que es importante su conservación y manejo en los ranchos ganaderos
Heterogeneous oxygen availability affects the titer and topology but not the fidelity of plasmid DNA produced by Escherichia coli
Jaen KE, Sigala J-C, Olivares-Hernandez R, Niehaus K, Lara AR. Heterogeneous oxygen availability affects the titer and topology but not the fidelity of plasmid DNA produced by Escherichia coli. BMC BIOTECHNOLOGY. 2017;17(1): 60.Background: Dissolved oxygen tension (DOT) is hardly constant and homogenously distributed in a bioreactor, which can have a negative impact in the metabolism and product synthesis. However, the effects of DOT on plasmid DNA (pDNA) production and quality have not been thoroughly investigated. In the present study, the effects of aerobic (DOT >= 30% air sat.), microaerobic (constant DOT = 3% air sat.) and oscillatory DOT (from 0 to 100% air sat.) conditions on pDNA production, quality and host performance were characterized. Results: Microaerobic conditions had little effect on pDNA production, supercoiled fraction and sequence fidelity. By contrast, oscillatory DOT caused a 22% decrease in pDNA production compared with aerobic cultures. Although in aerobic cultures the pDNA supercoiled fraction was 98%, it decreased to 80% under heterogeneous DOT conditions. The different oxygen availabilities had no effect on the fidelity of the produced pDNA. The estimated metabolic fluxes indicated substantial differences at the level of the pentose phosphate pathway and TCA cycle under different conditions. Cyclic changes in fermentative pathway fluxes, as well as fast shifts in the fluxes through cytochromes, were also estimated. Model-based genetic modifications that can potentially improve the process performance are suggested. Conclusions: DOT heterogeneities strongly affected cell performance, pDNA production and topology. This should be considered when operating or scaling-up a bioreactor with deficient mixing. Constant microaerobic conditions affected the bacterial metabolism but not the amount or quality of pDNA. Therefore, pDNA production in microaerobic cultures may be an alternative for bioreactor operation at higher oxygen transfer rates
StringENT test suite: ENT battery revisited for efficient P value computation
Random numbers play a key role in a wide variety of applications, ranging from mathematical simulation to cryptography. Generating random or pseudo-random numbers is not an easy task, especially when hardware, time and energy constraints are considered. In order to assess whether generators behave in a random fashion, there are several statistical test batteries. ENT is one of the simplest and most popular, at least in part due to its efficacy and speed. Nonetheless, only one of the tests of this suite provides a p value, which is the most useful and standard way to determine whether the randomness hypothesis holds, for a certain significance level. As a consequence of this, rather arbitrary and at times misleading bounds are set in order to decide which intervals are acceptable for its results. This paper introduces an extension of the battery, named StringENT, which, while sticking to the fast speed that makes ENT popular and useful, still succeeds in providing p values with which sound decisions can be made about the randomness of a sequence. It also highlights a flagrant randomness flaw that the classical ENT battery is not capable of detecting but the new StringENT notices, and introduces two additional tests.Depto. de Estadística e Investigación OperativaFac. de Ciencias MatemáticasTRUEpu
Supercritical extraction of lyophilized strawberry anthocyanins with pulsed electric fields pretreatment
Anthocyanins from LSB and with a PEF pretreatment were extracted with ethanol + SCCO2. The extraction at 200 bar, 333.15, 3.3% wt. of ethanol as cosolvent and using LSB with a PEF pretreatment of 1 kV/cm, produced an extraction yield of 0.284 % and a TAC of 0.231 (g/100 g of ethanol + SCCO2). The individual effect of 1.0 kV/cm of PEF pretreatment increases the %EY by 25 % and the TAC by 29 %. The individual effect of the cosolvent increases the %EY by 32% and that of TAC by 36.4%. However, the combined effect of 1.0 kV cm-1 and 3.3 % ethanol, produced an increase of 78.2 % and 85.3% in the %EY and TAC, respectively. Therefore, these results suggest that there is a synergistic effect, which means that both the electroporation caused by PEF in the LSB and the increase in polarity due to the addition of ethanol produce a substantial improvement over %ET and TAC. Furthermore, the process of extracting anthocyanins from LSB using a mixture of ethanol + supercritical carbon dioxide can be satisfactorily described by a solubility-based model such as the Kumar and Johnston model.The lyophilized strawberry anthocyanins were extracted using a supercritical extraction (SE) process. The effect of pulsed electric fields (PEF) as pretreatment and the influence of the addition of ethanol as a cosolvent on the percentage of extraction yield (EY) and the total anthocyanin concentration (TAC) were analyzed. The effect of PEF was evaluated at 0.5 and 1.0 kV/cm, while the effect of the cosolvent was studied in mixtures of supercritical carbon dioxide - ethanol (SCCO2 + ethanol) at 1.6 and 3.3% by weight. The best results (% EY = 0.506, TAC = 0.428 g /100 g of lyophilized strawberry) were obtained with a PEF pretreatment of 1.0 kV cm-1, 3.3%wt. ethanol at 200 bar and 333.15 K. The experimental results of solubility were suitably adjusted with the Kumar and Johnston model. The maximum solubility (0.114 g/100 g of solvent mixture) was obtained at 300 bar and 313.15 K.The authors would like to thank the National Council of Science and Technology of Mexico (CONACyT) for the scholarship granted to the master’s student in chemical sciences Marco A. Ávila-Hernández
Productive response of lambs fed Crescentia alata and Guazuma ulmifolia fruits in a tropical region of Mexico
polyethylene glycol (PEG) of the fruits of Crescentia alata and Guazuma ulmifolia was evaluated, the degradation kinetics of lamb diets with added fruit of the tree was determined, and the ration intake and growth rate of lambs fed these diets were measured. Twenty-five entire male lambs of 23.5± 0.44 kg body weight were used and distributed in treatments: T0 (control without fruit); T1 and T2, 15 and 30 % of the fruit of C. alata; and T3 and T4, 15 and 30 % of the fruit of G. ulmifoli
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