Estudio de la cristalización de ZrO2 en el sistema sol-gel: ZrO2-SiO2

Los polvos en el sistema ZrO2-SiO2, obtenidos por el método sol-gel, se produjeron utilizando alcóxido de silicio (TEOS) y propóxido de zirconio. Después de la gelación, se investigó la cristalización del ZrO2 por difracción de rayos X (DRX), análisis térmico (ATD/ATG), y microscopía electrónica de barrido (MEB). Los geles frescos eran amorfos. Se llevaron a cabo tratamientos térmicos de 100 hasta 1400°C, manteniéndolos por períodos de tiempo de hasta182h. La primera fase en cristalizar fue la zirconia tetragonal Z(t), entre 300 y 500°C. La temperatura de cristalización para las composiciones ricas en zirconia fue menor y aumentó a medida que el contenido de sílice aumentaba. El análisis térmico diferencial (ATD) mostró que la cristalización de Z(t) ocurría en dos pasos. La transformación de zirconia tetragonal a monoclínica ocurría a 1000°C y era claramente observada sólo en composiciones ricas en zirconia (>80%). La sílice permanecía amorfa hasta 1200°C, cuando se formaba la fase ZrSiO4. Se propuso un diagrama de fases sol-gel metaestable para mostrar el proceso de cristalización en el intervalo de temperatura de 100 a 1400°C

Caracterización nutritiva de centrosema macrocarpum, stylosanthes guianensis "tardío", stylosanthes macrocephala y zornia brasiliensis

Para el ensayo de alimentación se utilizó un diseño completamente al azar con cuatro tratamientos y cuatro repeticiones. Las unidades experimentales fueron carneros "africanos" con pesos metabólicos de 1118 ± 0_8 kgO.75. Se detectaron grandes diferencias en la calidad de las leguminosas. C. macrocarpum5065 tiene alto valor nutritivo, medido tanto en términos de concentración de proteínas como en consumo de nutrientes digestibles. S. macrocephala 1643 tiene alto potencial de consumo, a pesar de su baja proporción de hojas en relación a tallo en estado maduro, siendo compensada por la proporción de inflorescencia de un valor nutritivo y consumo altos. El consumo voluntario de S.guianensis "tardío"1283 es bajo, a pesar de su relativa buena proporción de hojas con relación a tallos en estado maduro. El consumo de Z. brasiliensis 7485 fue extremadamente bajo, lo cual se asocia con trastornos digestivos producidos por alcaloides.The objectives of this study were to determine the nutritive value of four promising tropical forage legumes from CIAT germplasm bank. A randomized complete block design with four treatments and four replications was used for the feeding trial, totalling 16 African sheep (11.28 ± 0_8 kgO.75) as experimental units. C. macrocarpum 5065 was found to have a very high nutritive value, measured both in terms of protein concentration and digestible nutrient intake. S_ macrocephala 1643 had high intake potential, despite its low leaf: stem ration when mature as a result of the considerable proportion of inflorescences with a high nutritive value and intake. S. guianensis 'tardío" had a low voluntary intake despite its relatively good leaf: stern ratio when mature Z. brasiliensis 7485 had an extremely low intake, which is associated with digestive disorders caused by alkaloids

Tuberculosis in pregnancy and adverse neonatal outcomes in two peruvian hospitals

Background: According to the World Health Organization, tuberculosis (TB) ranks among the top 10 causes of death worldwide. The significance of TB during pregnancy lies in its symptoms, which can be mistaken for physiological changes associated with pregnancy. This confusion can lead to maternal-perinatal complications. Objective: To evaluate the association between pulmonary TB in pregnancy and adverse neonatal outcomes in two Peruvian hospitals. Methods: This is a retrospective cohort study. The target population consisted of pregnant women with and without pulmonary TB whose deliveries were attended at two public hospitals, located in Lima, Peru. The adverse neonatal outcomes were prematurity, low birth weight (LBW), and being small for gestational age (SGA). Crude and adjusted relative risks (RRa) were calculated with their respective 95% confidence intervals (95%CI). Results: Information from 212 patients was analyzed; 48.1% had TB during pregnancy, and 23.1% had adverse neonatal outcomes (8%, 11.3%, and 12.3% for LBW, prematurity, and SGA, respectively). In the adjusted model, pregnant women with pulmonary TB had a 3.52 times higher risk of having a newborn with at least one of the adverse outcomes than those who were not exposed (aRR, 3.52; 95%CI: 1.93–6.68). Conclusion: Pulmonary TB in pregnancy was jointly and independently associated with adverse neonatal outcomes, including LBW, prematurity, and being SGA

Effect of polyunsaturated fatty acid deficiency on dipole relaxation in the membrane interface of rat liver microsomes

AbstractThe influence of a fat-free diet on the lipid dynamics of rat liver microsomes and liposomes of microsomal lipids was studied by using different fluorescence methods. Lifetime distribution and rotational diffusion of probes with different localization in the lipid bilayer were measured using multifrequency fluorometry. Lateral mobility was studied by measuring excimer formation of pyrenedodecanoic acid. Dipolar relaxation in the interfacial region was studied using 2-dimethylamino-6-lauroylnaphthalene (Laurdan). In spite of large changes in the fatty acid composition of microsomal lipids, polyunsaturated fatty acid deficiency showed no effect on the lifetime distribution and rotational mobility of 1,6-diphenyl-1,3,5-hexatriene (DPH), 1-(4-(trimethylamino)phenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH), 2-, 7- and 12-(9-anthroiloxy)stearic acids. The treatment did not change the lateral diffusion of pyrenedodecanoic acid, either. However, generalized polarization of Laurdan fluorescence was higher in polyunsaturated fatty acid deficient microsomes as compared to the polyunsaturated fatty acid sufficient ones. This effect was also observed in liposomes of the total microsomal lipids, indicating that the changes in fatty acid composition resulting from polyunsaturated fatty acid deficiency produced a small but significant decrease in the rate of dipolar relaxation in the region of the lipid polar groups of the bilayer. The absence of lipid gel phase domains in rat liver microsomes was also indicated by Laurdan fluorescence features

Rendimiento Productivo e Integridad Ósea de Pollos de Carne en Respuesta a Suplementación Dietaria con Cuatro Fuentes de Fitasa Comercial

The aim of this study was to determine the effects of four sources of commercial phytases on the performance and bone integrity of broilers from 1 to 28 days of age. Three hundred 1-day old Cobb 500 male chickens were distributed in 30 pens (10 birds per pen) and fed with the experimental diets for 28 days. The treatments were: T1, diet with adequate phosphorus (PAD); T2, phosphorus deficient diet (PDD); T3, PDD + phytase A (100 g/t); T4, PDD + phytase B (100 g/t); T5, PDD + phytase C (50 g/t) and T6, PDD + phytase D (50 g/t). Feeds and water were provided ad libitum. Body weight, body weight gain, feed consumption, feed conversion, and mortality were recorded weekly. At 28 days of age, 20 chicks per treatment were slaughtered to determine carcass and leg yield and tibia weight, plus bone moisture and ash content in the tibia. The results showed that the productive performance of broilers fed diets with normal levels of phosphorus (T1) were significantly higher (p<0.05) than chicks in the other treatments. Similarly, treatments T3 and T5 and treatments T4 and T6 presented similar responses, while T2 (deficient level of phosphorus) showed lower yields. Bone ash in all treatments, except for T2 (p<0.05), showed adequate levels. It was concluded that the productive responses of the birds that received diets deficient in phosphorus with the addition of phytase were lower than the level of response of the birds fed the diet with adequate level of phosphorus.El objetivo del presente ensayo fue determinar el efecto de cuatro fuentes de fitasas comerciales sobre el rendimiento productivo y la integridad ósea de pollos de carne de 1 a 28 días de edad. Se utilizaron 300 pollos BB machos de la Línea Cobb 500 distribuidos al azar en 30 corrales en piso (10 aves por corral), alimentados durante 28 días con uno de los siguientes tratamientos: T1, Dieta normal en fósforo (DNP); T2, Dieta deficiente en fósforo (DDP); T3, DDP + Fitasa A (100 g/t); T4, DDP + Fitasa B (100 g/t); T5, DDP + Fitasa C (50 g/t) y T6, DDP + Fitasa D (50 g/t). El suministro de alimento y agua fue ad libitum. El peso vivo, ganancia de peso, consumo de alimento, conversión alimentaria y mortalidad se registraron semanalmente. A los 28 días de edad, 20 aves por tratamiento fueron sacrificados para determinar el rendimiento de carcasa, rendimiento de piernas, peso de tibias y, posteriormente, contenidos de humedad y ceniza en tibias. Los resultados mostraron que el comportamiento productivo de los pollos de carne alimentados con niveles normales de fósforo (T1) fueron significativamente superiores (p<0.05) al resto de tratamientos; asimismo, los tratamientos T3 y T5 y los tratamientos T4 y T6 presentaron respuestas similares, mientras que T2 (nivel deficiente de fósforo), mostró rendimientos menores. Las tibias de las aves de los tratamientos, con excepción del T2 (p<0.05), mostraron niveles adecuados de cenizas. Se concluye que las respuestas productivas de las aves que recibieron la dieta deficiente en fósforo con la adición de fitasas fueron menores que el nivel de respuesta de las aves alimentadas con la dieta normal en fósforo

Pulmonary embolism response teams: Changing the paradigm in the care for acute pulmonary embolism

Pulmonary embolism response teams (PERTs) have emerged as a multidisciplinary, multispecialty team of experts in the care of highly complex symptomatic acute pulmonary embolism (PE), with a centralized unique activation process, providing rapid multimodality assessment and risk stratification, formulating the best individualized diagnostic and therapeutic approach, streamlining the care in challenging clinical case scenarios (e.g., intermediate-high risk and high-risk PE), and facilitating the implementation of the recommended therapeutic strategies on time. PERTs are currently changing how complex acute PE cases are approached. The structure, organization, and function of a given PERT may vary from hospital to hospital, depending on local expertise, specific resources, and infrastructure for a given academic hospital center. Current emerging data demonstrate the value of PERTs in improving time to PE diagnosis; shorter time to initiation of anticoagulation reducing hospital length of stay; increasing use of advanced therapies without an increase in bleeding; and in some reports, decreasing mortality. Importantly, PERTs are positively impacting outcomes by changing the paradigm of care for acute PE through global adoption by the health-care community

PRODUCTIVIDAD DE DOS CULTIVARES DE PASTO Brachiaria brizantha (LA LIBERTAD Y MULATO), HACIENDA LAS MERCEDES, UNA, MANAGUA, NICARAGUA

Con el objeto de contribuir a un mejor uso y manejo de dos cultivares del pasto Brachiaria brizantha (La Libertad y Mulato), durante el periodo lluvioso del año 2005, se llevo a cabo un estudio en la finca las Mercedes propiedad de la UNA. La finca las Mercedes, se ubica en las coordenadas 12°09’28’’ latitud norte y 86°10’16’’ longitud oeste. Para el estudio se utilizaron áreas de pasto de Brachiaria, 2.8 ha con el cultivar la libertad y 2.1 ha con el cultivar Mulato. Se realizaron cortes cada 15 días, en un área de 0.35 ha para cada cultivar, en la cual se determinó la producción de biomasa total fresca y seca, así como la producción de la fracción de la planta (hoja y tallo), y la relación entre estos. Se realizó además análisis de calidad (nitrógeno proteico). En la toma de datos de campo, se empleo el método de doble muestreo. Para la determinación de la composición botánica se utilizó el método de rango de peso seco o comparativo. Finalmente se realizó un análisis sobre el uso de la pastura Brachiaria y la proyección de su uso futuro, encontrándose que el cv Mulato presentó mejor producción de biomasa seca (635 kg / ms /ha / corte) y producción de hojas (5156 kg/ ms /ha /corte), relación hoja tallo de 1.2, así como contenido de nitrógeno proteico (4.2). Según el estudio de composición botánica, la mayor (Plt;0.05) cobertura correspondió al pasto brachiaria con rangos mayores al 95%. Le siguen algunas algunas especies leguminosas como Mimosa púdica (dormilona) y arvenses como Sida spp (escoba lisa). El análisis de uso permitió determinar que las pasto Brachiaria brizantha cvs La Libertad y Mulato han sido subutilizado, manteniéndose cargas que pueden ser duplicadas.  Además de que la producción de estos cultivares podrían mejorar si se les proporciona una mejor fertilización. Abreviaturas  UNA: Universidad Nacional Agraria; Cv: cultivar;CIAT: Centro Internacional de Agricultura Tropical; INETER: Instituto Nacional de Estudios Territoriales

Could Physical Fitness Be Considered as a Protective Social Factor Associated with Bridging the Cognitive Gap Related to School Vulnerability in Adolescents? The Cogni-Action Project

Carlos Cristi-Montero received funding for the Cogni-Action Project from the National Commission for Scientific and Technological Research CONICYT/FONDECYT INICIACION 2016 grant No. 11160703 (Chile), and the National Research and Development Agency (ANID) from Chile-2019, Postdoctoral Grant No. 74200071.The first aim was to compare differences between school vulnerability groups, fitness levels, and their combination in adolescent cognitive performance. The second aim was to determine the mediation role of fitness in the association between school vulnerability and cognitive performance. A total of 912 Chilean adolescents aged 10–14 years participated in this study. The school vulnerability index (SVI) assigned by the Chilean Government was categorized into high-, mid-, or low-SVI. Adolescents were classified as fit or unfit according to their global fitness z-score computed from their cardiorespiratory (CRF), muscular (MF), and speed/agility fitness (SAF) adjusted for age and sex. A global cognitive scorewas estimated through eight tasks based on a neurocognitive battery. Covariance and mediation analyses were performed, adjusted for sex, schools, body mass index, and peak high velocity. Independent analyses showed that the higher SVI, the lower the cognitive performance (F(6,905) = 18.5; p < 0.001). Conversely, fit adolescents presented a higher cognitive performance than their unfit peers (F(5,906) = 8.93; p < 0.001). The combined analysis found cognitive differences between fit and unfit adolescents in both the high- and mid-SVI levels (Cohen’s d = 0.32). No differences were found between fit participants belonging to higher SVI groups and unfit participants belonging to lower SVI groups. Mediation percentages of 9.0%, 5.6%, 7.1%, and 2.8% were observed for the global fitness score, CRF, MF, and SAF, respectively. The mediation effect was significant between lowwith mid-high-SVI levels but not between mid- and high-SVI levels. These findings suggest that an adequate physical fitness level should be deemed a protective social factor associated with bridging the cognitive gap linked to school vulnerability in adolescents. This favourable influence seems to be most significant in adolescents belonging to a more adverse social background.National Commission for Scientific and Technological Research CONICYT/FONDECYT INICIACION (Chile) 11160703National Research and Development Agency (ANID) from Chile 7420007