1,241 research outputs found

    Efectividad de los ejercicios nórdicos sobre la incidencia de lesiones de isquiotibiales en futbolistas profesionales y amateur masculinos entre los 15 y 41 años. Revisión sistemática

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    Introduction: muscular injuries are the most common among soccer players, being hamstring injury the most frequent. Objective: The aim of this study was to analyze the existing evidence on the effects of Nordic exercises on the incidence of hamstring injuries in professional and amateur male soccer players between 15 and 41 years of age. Methods: A systematic review was carried out following the PRISMA guidelines recommendations, a search was carried out for articles in PubMed, BVS, Cochrane, Web OF Science and SCOPUS, in addition Google Scholar was consulted. The search was performed based on the PICO strategy with the following terms: hamstring muscles, exercise, rehabilitation, therapy, athletic injuries, soccer. Results: a total of 257 articles resulted from the search, 5 of which were included in this study. All studies showed positive effects of Nordic exercises for athletes. Conclusions: Nordic exercises reduced the incidence of hamstring injury in 4 of the studies analyzed, the percentage of compliance with the intervention sessions conditioned the quality of the effects while the moment of application of the intervention (pre- or post-training) had no influence.Introducción: Las lesiones musculares son comunes en futbolistas, siendo la lesión de isquiotibiales la más frecuente. Objetivo: Analizar la evidencia existente sobre los efectos de los ejercicios nórdicos en la incidencia de lesiones de isquiotibiales en jugadores de fútbol profesional y amateur masculinos entre los 15 y 41 años. Materiales y métodos: Se llevó a cabo una revisión sistemática siguiendo las recomendaciones de la declaración PRISMA, realizando la búsqueda de artículos en PubMed, BVS, Cochrane, Web OF Science y SCOPUS, además de consultar Google Scholar. La búsqueda se realizó basada en la estrategia PICO con los siguientes términos: hamstring muscles, exercise, rehabilitation, therapy, athletic injuries, soccer. Resultados: un total de 257 artículos resultaron de la búsqueda, siendo 5 los artículos incluidos en este estudio. Todos los estudios evidenciaron efectos positivos de los ejercicios nórdicos para los deportistas. Conclusiones: los ejercicios nórdicos redujeron la incidencia de lesión de isquiotibiales en 4 de los estudios analizados, el porcentaje de cumplimiento de las sesiones de intervención condicionaron la calidad de los efectos mientras que el momento de aplicación de la intervención (pre- o post-entreno) no influy

    Aharonov-Bohm interferences from local deformations in graphene

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    One of the most interesting aspects of graphene is the tied relation between structural and electronic properties. The observation of ripples in the graphene samples both free standing and on a substrate has given rise to a very active investigation around the membrane-like properties of graphene and the origin of the ripples remains as one of the most interesting open problems in the system. The interplay of structural and electronic properties is successfully described by the modelling of curvature and elastic deformations by fictitious gauge fields that have become an ex- perimental reality after the suggestion that Landau levels can form associated to strain in graphene and the subsequent experimental confirmation. Here we propose a device to detect microstresses in graphene based on a scanning-tunneling-microscopy setup able to measure Aharonov-Bohm inter- ferences at the nanometer scale. The interferences to be observed in the local density of states are created by the fictitious magnetic field associated to elastic deformations of the sample.Comment: Some bugs fixe

    Standardization for oncologic head and neck surgery

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    The inherent variability in performing specific surgical procedures for head and neck cancer remains a barrier for accurately assessing treatment outcomes, particularly in clinical trials. While non-surgical modalities for cancer therapeutics have evolved to become far more uniform, there remains the challenge to standardize surgery. The purpose of this review is to identify the barriers in achieving uniformity and to highlight efforts by surgical groups to standardize selected operations and nomenclature. While further improvements in standardization will remain a challenge, we must encourage surgical groups to focus on strategies that provide such a level.Peer reviewe

    Assessment of Hyperbolic Heat Transfer Equation in Theoretical Modeling for Radiofrequency Heating Techniques

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    Theoretical modeling is a technique widely used to study the electrical-thermal performance of different surgical procedures based on tissue heating by use of radiofrequency (RF) currents. Most models employ a parabolic heat transfer equation (PHTE) based on Fourier’s theory, which assumes an infinite propagation speed of thermal energy. We recently proposed a one-dimensional model in which the electrical-thermal coupled problem was analytically solved by using a hyperbolic heat transfer equation (HHTE), i.e. by considering a non zero thermal relaxation time. In this study, we particularized this solution to three typical examples of RF heating of biological tissues: heating of the cornea for refractive surgery, cardiac ablation for eliminating arrhythmias, and hepatic ablation for destroying tumors. A comparison was made of the PHTE and HHTE solutions. The differences between their temperature profiles were found to be higher for lower times and shorter distances from the electrode surface. Our results therefore suggest that HHTE should be considered for RF heating of the cornea (which requires very small electrodes and a heating time of 0.6 s), and for rapid ablations in cardiac tissue (less than 30 s)

    Extended Y chromosome haplotypes resolve multiple and unique lineages of the Jewish priesthood

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    It has been known for over a decade that a majority of men who self report as members of the Jewish priesthood (Cohanim) carry a characteristic Y chromosome haplotype termed the Cohen Modal Haplotype (CMH). The CMH has since been used to trace putative Jewish ancestral origins of various populations. However, the limited number of binary and STR Y chromosome markers used previously did not provide the phylogenetic resolution needed to infer the number of independent paternal lineages that are encompassed within the Cohanim or their coalescence times. Accordingly, we have genotyped 75 binary markers and 12 Y-STRs in a sample of 215 Cohanim from diverse Jewish communities, 1,575 Jewish men from across the range of the Jewish Diaspora, and 2,099 non-Jewish men from the Near East, Europe, Central Asia, and India. While Cohanim from diverse backgrounds carry a total of 21 Y chromosome haplogroups, 5 haplogroups account for 79.5% of Cohanim Y chromosomes. The most frequent Cohanim lineage (46.1%) is marked by the recently reported P58 T->C mutation, which is prevalent in the Near East. Based on genotypes at 12 Y-STRs, we identify an extended CMH on the J-P58* background that predominates in both Ashkenazi and non-Ashkenazi Cohanim and is remarkably absent in non-Jews. The estimated divergence time of this lineage based on 17 STRs is 3,190 ± 1,090 years. Notably, the second most frequent Cohanim lineage (J-M410*, 14.4%) contains an extended modal haplotype that is also limited to Ashkenazi and non-Ashkenazi Cohanim and is estimated to be 4.2 ± 1.3 ky old. These results support the hypothesis of a common origin of the CMH in the Near East well before the dispersion of the Jewish people into separate communities, and indicate that the majority of contemporary Jewish priests descend from a limited number of paternal lineages

    Prevalence of transfusion-transmitted Chagas disease among multitransfused patients in Brazil

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    <p>Abstract</p> <p>Background</p> <p>Blood transfusion has always been an important route for Chagas Disease (CD) transmission. The high prevalence of CD in Latin America and its lifelong asymptomatic clinical picture pose a threat for the safety of the blood supply. The outcome of measures designed to improve transfusion safety can be assessed by evaluating the prevalence of CD among multitransfused patients</p> <p>Methods</p> <p>In order to assess the impact of CD control measures on the safety of the blood supply, an observational cross-sectional study was designed to determine the prevalence of CD in 351 highly transfused patients, in which vectorial transmission was excluded. This study compared patients that received transfusion products before (n = 230) and after (n = 121) 1997, when measures to control transfusion-transmitted CD were fully implemented in Brazil.</p> <p>Results</p> <p>The study group consisted of 351 patients exposed to high numbers of blood products during their lifetime (median number of units transfused = 51, range 10–2086). A higher prevalence of transfusion-transmitted CD (1.30%) was observed among multitransfused patients that received their first transfusion before 1997, compared with no cases of transfusion-transmitted CD among multitransfused patients transfused after that year. The magnitude of the exposure to blood products was similar among both groups (mean number of units transfused per year of exposure = 25.00 ± 26.46 and 23.99 ± 30.58 respectively; P = 0.75, Mann-Whitney test).</p> <p>Conclusion</p> <p>Multiple initiatives aimed to control vector and parental transmission of CD can significantly decrease transfusion-transmitted CD in Brazil. Our data suggest that mandatory donor screening for CD represents the most important measure to interrupt transmission of CD by blood transfusions.</p

    No Benefit from Chronic Lithium Dosing in a Sibling-Matched, Gender Balanced, Investigator-Blinded Trial Using a Standard Mouse Model of Familial ALS

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    Background: In any animal model of human disease a positive control therapy that demonstrates efficacy in both the animal model and the human disease can validate the application of that animal model to the discovery of new therapeutics. Such a therapy has recently been reported by Fornai et al. using chronic lithium carbonate treatment and showing therapeutic efficacy in both the high-copy SOD1G93A mouse model of familial amyotrophic lateral sclerosis (ALS), and in human ALS patients. Methodology/Principal Findings: Seeking to verify this positive control therapy, we tested chronic lithium dosing in a sibling-matched, gender balanced, investigator-blinded trial using the high-copy (average 23 copies) SOD1G93A mouse (n = 27–28/group). Lithium-treated mice received single daily 36.9 mg/kg i.p. injections from 50 days of age through death. This dose delivered 1 mEq/kg (6.94 mg/kg/day lithium ions). Neurological disease severity score and body weight were determined daily during the dosing period. Age at onset of definitive disease and survival duration were recorded. Summary measures from individual body weight changes and neurological score progression, age at disease onset, and age at death were compared using Kaplan-Meier and Cox proportional hazards analysis. Our study did not show lithium efficacy by any measure. Conclusions/Significance: Rigorous survival study design that includes sibling matching, gender balancing, investigato

    Characterisation of thermo-hygrometric conditions of an archaeological site affected by unlike boundary weather conditions

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    This paper applies statistical techniques to analyse microclimatic data (temperature and relative humidity) recorded at the archaeological site of Plaza de l'Almoina (Valencia, Spain). This study has allowed us to quantify the effect of certain measures that were adopted for preventive conservation. The first monitoring campaign took place in 2010 at this archaeological site, showing harmful effects on the conservation state of the remains due to the presence of a skylight that partly covers the remains and causes a greenhouse effect. This skylight was covered with a water layer to prevent overheating of this archaeological site. However, this layer was removed in 2013 due to water leaks, and the indoor conditions changed. Over the summer, a temporary canvas was installed over the skylight to avoid heating of the archaeological site below by preventing the incidence of direct sunlight. The main importance of this work was to characterise the effect of unlike boundary weather conditions of different years in the indoor microclimate of the archaeological site, and to study the effect of the new boundary situation. This paper shows that the removal of water from the skylight caused a temperature increase inside the museum; meanwhile, the subsequent installation of the canvas cover allows appropriate daily cycles of temperature and relative humidity, especially in areas under the skylight. This work also shows that the replacement of a water ditch near the archaeological site by a PVC pipe was also detected by the sensors due to the difference in water vapour pressure.This work was partially supported by the Spanish Government (Ministerio de Ciencia e Innovacion) with grants numbers HAR2010-21944-C02-01 and HAR2010-21944-C02-02. The authors thank the personal collaboration of the archaeologist Albert Ribera and Carmen Perez.Merello Gimenez, P.; Fernández Navajas, A.; Curiel Esparza, J.; Zarzo Castelló, M.; García Diego, FJ. (2014). Characterisation of thermo-hygrometric conditions of an archaeological site affected by unlike boundary weather conditions. Building and Environment. 76:125-133. doi:10.1016/j.buildenv.2014.03.009S1251337
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