85 research outputs found

    Electrical Properties and Electromagnetic Interference Shielding Effectiveness of Interlayered Systems Composed by Carbon Nanotube Filled Carbon Nanofiber Mats and Polymer Composites

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    The demand for multifunctional requirements in aerospace, military, automobile, sports, and energy applications has encouraged the investigation of new composite materials. This study focuses on the development of multiwall carbon nanotube (MWCNT) filled polypropylene composites and carbon nanofiber composite mats. The developed systems were then used to prepare interlayered composites that exhibited improved electrical conductivity and electromagnetic interference (EMI) shielding efficiency. MWCNT-carbon nanofiber composite mats were developed by centrifugally spinning mixtures of MWCNT suspended in aqueous poly(vinyl alcohol) solutions. The developed nanofibers were then dehydrated under sulfuric acid vapors and then heat treated. Interlayered samples were fabricated using a nanoreinforced polypropylene composite as a matrix and then filled with carbon fiber composite mats. The in-plane and through-plane electrical conductivity of an eight-layered flexible carbon composite (0.65 mm thick) were shown to be 6.1 and 3.0 × 10−2 S·cm−1, respectively. The EMI shielding effectiveness at 900 MHz increased from 17 dB for the one-layered composite to 52 dB for the eight-layered composite. It was found that the reflection of the electromagnetic waves was the dominating mechanism for EMI shielding in the developed materials. This study opens up new opportunities for the fabrication of novel lightweight materials that are to be used in communication systems

    ¿Son el bajo nivel de condición física y la obesidad dos características del adolescente con síndrome de Down?

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    Introduction: “Obesity” is considered a feature of youth with DS but whether “low physical fitness” is also a feature is unknown. Objective: The aim of this case-control study was to compare the levels of fatness and fitness in adolescents with and without DS. Methods: Participants included 17 (5 girls) adolescents with DS aged 12-18 years and a control group of 94 (45 girls) adolescents without DS aged 12-16 years. The ALPHA health-related fitness test battery for children and adolescents was selected to assess fatness and fitness in both groups. Results: There were no differences in levels of fatness between groups (all P > 0.27). Adolescents with DS had lower levels of fitness in all the tests than adolescents without DS (all P < 0.001). Conclusion: Adolescents with DS have similar levels of fatness and lower levels of fitness than their peers without DSIntroducción: La obesidad es considerada una característica de los jóvenes con SD, sin embargo se desconoce si la “baja condición física” también lo es. Objetivo: Comparar los niveles de obesidad y condición física en adolescentes con y sin SD. Métodos: Participaron 17 adolescentes (5 niñas) con SD de 12 a 18 años y un grupo control de 94 (45 niñas) adolescentes sin SD de 12-16 años de edad. La batería de condición física ALPHA relacionada con la salud para niños y adolescentes fue seleccionada para evaluar la obesidad y la condición física en ambos grupos. Resultados: No se encontraron diferencias en los niveles de obesidad entre grupos (P > 0,27). Los adolescentes con SD tuvieron niveles más bajos de condición física en todos los test en comparación con los adolescentes sin SD (P < 0,001). Conclusión: Los adolescentes con SD tienen niveles similares de obesidad y menores de condición física que sus compañeros sin SD.The UP&DOWN study was supported by the Spanish Ministry of Economy and Competitiveness (DEP 2010-21662-C04). JRR was supported by a contract from the Spanish Ministry of Science and Innovation (RYC-2010-05957

    Bottom-up control of common octopus Octopus vulgaris in the Galician upwelling system, northeast Atlantic Ocean

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    This paper investigates the possible underlying causes of the wide interannual fluctuations in catch of the common octopus Octopus vulgaris Cuvier, 1797 in one of the main small-scale fisheries off the coast of Galicia (northwest Spain). Galicia is at the northern boundary of the Iberian–Canary current upwelling system in the northeast Atlantic Ocean, where local winds induce seasonal upwelling, largely driving the annual cycles of primary and secondary production. We hypothesize that such dynamics are also fundamental for the survival of the planktonic stages of octopus and set the year class strength. We address this hypothesis by investigating the influence of upwelling on time-series of octopus fishery data. Wind stress structure during the spring–summer (prior to the hatching peak) and autumn–winter (during the planktonic stage) was found to affect the early life phase of this species, and explains up to 85% of the total variance of the year-to-year variability of the adult catch. Despite this bottom-up modulation via environmental conditions, our results also provide evidence for a between-cohort density-dependent interaction, probably caused by cannibalism and competition for habitat.Postprin

    Fisheries and Oceanography off Galicia, NW Spain: Mesoscale Spatial and Temporal Changes in Physical Processes and Resultant Patterns of Biological Productivity

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    The Galician shelf off NW Spain (43N degrees 9W degrees) exhibits mesoscale spatial and temporal changes in biological productivity associated with upwelling. Spatial heterogeneity results from local geomorphic and land-sea interactions superimposed on the large scale atmospheric processes that produce upwelling. Wind-induced upwelling events, commonly of short (i.e., week) duration, are more common in the summer than in the winter. A Series of cruises, including some time series sampling, and satellite imagery analysis showed that surface upwelling was more common and persistent on the northern coast compared with the western coast off the coastal embayments, the Rias Bajas. Nearshore off the rias, coastal runoff, which is greater in the rainy winter/spring versus the dry summer, affected upwelling. In early summer, upwelling less often reaches the surface because of increased water column stratification associated with lower surface salinities and thus upwelling is not detected by satellite imagery. Conversely, in late summer, upwelling more often reaches the surface because coastal runoff is reduced during the dry summer months and the water column tends to be less stratified. Plankton biomass and rate processes along the Galician shelf reflected both ambient hydrographic conditions as well as prior history of upwelling or downwelling. Phytoplankton and bacterioplankton were in greatest abundance during upwelling conditions (June through August); in contrast, both zooplankton and fish larvae exhibited highest abundances in March, when there were upwelling conditions prior to our cruise. Spatial differences in the duration and frequency of upwelling events, in combination with advection of water masses, are critical to the patterns of water column productivity and sardine fisheries production off the Galician coast. More persistent upwelling at this NW corner of the Iberian peninsula Supports large sardine fisheries because zooplankton and larval fish populations have time to respond to the higher primary production. Farther down the western Galician coast, the episodic upwelling and resultant intermittent primary production does not support a stable food supply needed to support fisheries. Times series sampling revealed mean response times of bacteria, phytoplankton, and zooplankton to be on the order of a day, days, and weeks, respectively. Sardines showed no spawning response in the relatively short time series sampling. The observed distributional patterns of fish eggs and larvae showed some offshore transport of fish larvae that were spawned inshore during upwelling periods and aggregation of larvae in a convergence zone northwest of Cabo Villano

    Eficàcia i seguretat d’un tractament oral a base de mucopolisacàrids, col·lagen tipus I i vitamina C en pacients amb tendinopaties

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    Introducció i objectius La tendinopatia és una lesió freqüent durant la pràctica esportiva que es manifesta amb una alteració estructural del tendó. L’objectiu d’aquest estudi fou avaluar l’eficàcia i la seguretat d’un complement alimentari a base de mucopolisacàrids, col·lagen tipus i i vitamina C (Tendoactive®) sobre l’evolució clínica i estructural de les tendinopaties del tendó d’Aquil·les, del rotular i de l’epicòndil lateral del colze. Material i mètodes Es realitzà un estudi multicèntric prospectiu, de tipus exploratori en fase iv, obert i no comparatiu. S’inclogueren un total de 98 pacients amb tendinopaties (32 d’Aquil·les, 32 de rotular i 34 de l’epicòndil lateral) que reberen una dosi diària de 435 mg de mucopolisacàrids, 75 mg de col·lagen tipus i i 60 mg de vitamina C (equivalent a 3 càpsules al dia de Tendoactive®) durant 90 dies consecutius. Mensualment s’avaluà el dolor en repòs i en activitat mitjançant una escala visual analògica (EVA), la funció articular mitjançant els qüestionaris VISA-A, VISA-P i PRTEE, i el tendó afectat es caracteritzà ecogràficament. Resultats En els 3 tipus de tendinopatia es registrà una reducció significativa del dolor, tant en repòs com en activitat, des de la primera visita de control (dia 30) fins al final de l’estudi (dia 90). Així mateix, el dia 90 es detectà una millora del 38% en VISA-A, del 46% en VISA-P i del 77% en PRTEE (p < 0,001). Simultàniament es registrà una reducció del 12% en el gruix del tendó d’Aquil·les, del 10% en el rotular i del 20% en el tendó de l’epicòndil lateral (p < 0,05). Conclusions Els resultats de l’estudi indiquen que l’administració de Tendoactive® és segura i eficaç per millorar els símptomes clínics i l’evolució estructural de les tendinopaties del tendó d’Aquil·les, del tendó rotular i del tendó de l’epicòndil lateral

    The efficacy and safety of oral mucopolysaccharide, type I collagen and vitamin C treatment in tendinopathy patients

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    Introduction and objectives Tendinopathy, which is accompanied by structural changes to the tendon, is a common sporting injury. The aim of this study was to evaluate the efficacy and safety of a nutritional supplement containing mucopolysaccharides, type I collagen and vitamin C (TendoactiveTM) on the clinical and structural evolution of tendinopathies of the Achilles tendon, patellar tendon and lateral epicondyle tendon in the elbow. Materials and methods A multicenter, open-label, non-comparative, prospective, exploratory phase iv study was performed. A total of 98 tendinopathy patients (32 Achilles, 32 patellar and 34 lateral epicondylar), who received a daily dose of 435 mg mucopolysaccharides, 75 mg type i collagen and 60 mg vitamin C (equivalent to three capsules of TendoactiveTM per day) for 90 consecutive days, were included. Every month, pain at rest and when active was assessed using a visual analogue scale (VAS), joint function was assessed using the VISA-A, VISA-P and PRTEE questionnaires, and the tendon affected was characterized by ultrasound. Results A significant reduction in pain both at rest and when active was observed between the first control visit (day 30) and the end of the study (day 90) for all three types of tendinopathy. Thus, a 38% improvement in VISA-A, 46% in VISA-P and 77% in PRTEE was observed on day 90 (P < .001). Similarly, a 12% decrease in the thickness of the Achilles tendon, a 10% decrease in the patellar tendon and a 20% decrease in the lateral epicondyle tendon was observed (P < .05). Conclusions The results of this study show that the administration of TendoactiveTM is safe and effective for improving the clinical symptoms and structural evolution of tendinopathies of the Achilles, patella and lateral epicondyle tendons

    Eficacia y seguridad de un tratamiento oral a base de mucopolisacáridos, colágeno tipo i y vitamina C en pacientes con tendinopatías

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    Introducción y objetivos La tendinopatía es una lesión frecuente durante la práctica deportiva que cursa con una alteración estructural del tendón. El objetivo de este estudio fue evaluar la eficacia y la seguridad de un complemento alimentario a base de mucopolisacáridos, colágeno tipo i y vitamina C (Tendoactive®) sobre la evolución clínica y estructural de las tendinopatías del tendón de Aquiles, rotuliano y del epicóndilo lateral del codo. Material y métodos Se realizó un estudio multicéntrico prospectivo, de tipo exploratorio en fase iv , abierto y no comparativo. Se incluyeron un total de 98 pacientes con tendinopatías (32 de Aquiles, 32 de rotuliano y 34 del epicóndilo lateral) que recibieron una dosis diaria de 435 mg de mucopolisacáridos, 75 mg de colágeno tipo i y 60 mg de vitamina C (equivalente a 3 cápsulas al día de Tendoactive®) durante 90 días consecutivos. Mensualmente se evaluó el dolor en reposo y en actividad mediante una escala visual analógica (EVA), la función articular mediante los cuestionarios VISA-A, VISA-P y PRTEE, y se caracterizó ecográficamente el tendón afectado. Resultados En los 3 tipos de tendinopatía se registró una reducción significativa del dolor tanto en reposo como en actividad desde la primera visita de control (día 30) hasta el final del estudio (día 90). Asimismo el día 90 se detectó una mejora del 38% en VISA-A, del 46% en VISA-P y del 77% en PRTEE (p < 0,001). Simultáneamente se registró una reducción del 12% en el grosor del tendón de Aquiles, del 10% en el rotuliano y del 20% en el tendón del epicóndilo lateral (p < 0,05). Conclusiones Los resultados del estudio indican que la administración de Tendoactive® es segura y eficaz para mejorar los síntomas clínicos y la evolución estructural de las tendinopatías del tendón de Aquiles, tendón rotuliano y tendón del epicóndilo lateral

    Explorando la celula de origen y los programas transcripcionales patologicos en mieloma multiple (MM) y amiloidosis de cadena ligera (AL) mediante la diseccion del desarrollo de la celula plasmatica (CP) normal

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    CO-009 MM y AL son las dos gammapatias monoclonales malignas más comunes. Los intentos para identificar las diferencias genéticas entre ambas han tenido poco éxito. Además, se desconoce si MM y AL emergen del mismo compartimento de CPs normales. Nos proponemos definir el atlas trancripcional del desarrollo de la CP normal en sangre periférica (SP) y medula ósea (MO), y compararlo con el programa transcripcional de las CPs clonales de MM y AL. Se estudiaron 93 individuos, en 7 donantes sanos (DS), se aislaron CP de SP según su isotipo de cadena pesada (IgG, IgA and IgM). Adicionalmente, se obtuvieron 5 subpoblaciones de CP de MO basadas en la expresión de CD19, CD39, CD81 y CD56. Las CPs clonales de pacientes con MM (n=38) y AL (n=41) se separaron mediante FACS por fenotipo aberrante especifico de paciente. Para estudiar poblaciones de CP con un reducido numero de células aisladas, empleamos un método de RNAseq de alta sensibilidad (MARS-seq). Se realizaron todas las comparaciones pareadas posibles de expresión diferencial (Deseq2). Se generaron datos de expresión mediante single-cell RNAseq (scRNAseq, 10xGenomics) de un total de 35, 910 PCs de 3 HA, 2 MM and 2 AL, que fueron analizados de manera integrada con el paquete Seurat en R. ..

    International Lower Limb Collaborative Paediatric subpopulation analysis (INTELLECT-P) study: multicentre, international, retrospective audit of paediatric open fractures

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    Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

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    Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe
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