Influencia de los parámetros biomecánicos en el rendimiento y la economía de corredores de fondo aficionados

Los objetivos de este estudio son analizar la relación entre las variables biomecánicas, la economía de carrera y el rendimiento en corredores de fondo aficionados. Además, determinar si existe algún cambio en los parámetros biomecánicos coincidente con el umbral anaeróbico ventilatorio. Participaron 10 corredores de fondo aficionados realizando: Antropometría, batería de saltos verticales, prueba de economía de carrera y prueba de consumo máximo de oxígeno. Estas últimas realizadas en tapiz rodante, registrándose parámetros fisiológicos (ventilatorios y frecuencia cardiaca) y biomecánicos (tiempos de contacto y de vuelo, frecuencia y amplitud de zancada, “duty factor”). Por primera vez, se ha observado una relación entre parámetros biomecánicos espacio-temporales de la carrera (frecuencia y amplitud de zancada), el rendimiento y la economía de carrera. Además, se ha comprobado que la aparición del umbral anaeróbico ventilatorio se encuentra relacionada con cambios en la biomecánica de la carrera (fundamentalmente “duty factor” y amplitud de zancada). Las relaciones encontradas entre las variables antropométricas y de salto, economía de carrera y rendimiento están en consonancia con las mencionadas en estudios previos, así como que la relación entre la economía de carrera y el rendimiento. Futuros trabajos deberían realizarse en corredores de mayor nivel para contrastar estos hallazgos.The aim of this study is to analyze the relationship between running biomechanics, running economy and performance in recreational long distance runners. Additionally, determine if there is any change in running biomechanical parameters that coincides with the anaerobic threshold. Ten recreational runners performed an anthropometric evaluation, a battery of vertical jumps, a running economy test and a maximal incremental test. Both running tests were performed in a treadmill, registering simultaneously physiological (ventilation and heart rate) and biomechanical (contact and flight times, stride length and rate, “duty factor”) parameters. A relationship between running biomechanics (step length and rate), running economy and performance was obtained. Furthermore, the appearance of the ventilatory anaerobic threshold was related with changes in running biomechanics (mainly with “duty factor” and step length). The relationships between anthropometry and vertical jumps’ parameters, running economy and performance still consistent with those identified in previous studies, as well as the relationship between running economy and performance. Future studies should be done with a higher level sample to contrast these findings.Peer Reviewe

Propuesta de plan de manejo ambiental a partir de los indicadores de "GreenMetric ranking" para la Universidad Católica de Colombia

Trabajo de InvestigaciónEn la primera parte de esta investigación, se muestra como en los últimos años la gestión ambiental dentro de las diferentes organizaciones ha adquirido una mayor relevancia; es así como la presente propuesta tuvo como fin estudiar los indicadores desarrollados por el reconocido programa GreenMetric ranking, creado por la Universidad de Indonesia en el año 2010, aplicándolos a un plan de manejo ambiental en la Universidad Católica de Colombia. Teniendo como guía y basados en este programa se pudo diagnosticar, evaluar y crear la propuesta de manejo ambiental dirigida a la Universidad detectando las falencias y debilidades encontradas a lo largo de esta investigación, estudiando los indicadores y criterios de evaluación usados por GreenMetric, que cubren aspectos como infraestructura, energía y cambio climático, agua, residuos, transporte y educación. Se entenderá la importancia que tiene cada uno de estos indicadores especialmente diseñados para evaluar Instituciones de educación superior, y cómo el estar desalineado con ellos implica que la Universidad Católica de Colombia no sea ambientalmente amigable.INTRODUCCIÓN 1. GENERALIDADES 2. DIAGNOSTICO UNIVERSIDAD CATÓLICA DE COLOMBIA 3. EVALUACIÓN GREENMETRIC 4. PROPUESTA PLAN DE MANEJO AMBIENTAL 5. CONCLUSIONES 6. RECOMENDACIONES BIBLIOGRAFÍA ANEXOSPregradoIngeniero Civi

The first Hochschild cohomology group of a schurian cluster-tilted algebra

Given a cluster-tilted algebra B we study its first Hochschild cohomology group HH1(B) with coefficients in the B-B-bimodule B. We find several consequences when B is representation-finite, and also in the case where B is cluster-tilted of type Ã.Fil: Assem, Ibrahim. University of Sherbrooke; CanadáFil: Redondo, Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Matemática Bahía Blanca. Universidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática Bahía Blanca; Argentin

Clinical and epidemiological characterization of a lymphogranuloma venereum outbreak in Madrid, Spain: co-circulation of two variants

AbstractThe lymphogranuloma venereum (LGV) outbreak described in the Netherlands in 2003, increased the interest in the genotyping of Chlamydia trachomatis. Although international surveillance programmes were implemented, these studies slowly decreased in the following years. Now data have revealed a new accumulation of LGV cases in those European countries with extended surveillance programmes. Between March 2009 and November 2011, a study was carried out to detect LGV cases in Madrid. The study was based on screening of C. trachomatis using commercial kits, followed by real-time pmpH-PCR discriminating LGV strains, and finally ompA gene was sequenced for phylogenetic reconstruction. Ninety-four LGV infections were identified. The number of cases increased from 10 to 30 and then to 54 during 2009–2011. Incidence of LGV was strongly associated with men who have sex with men; but in 2011, LGV cases were described in women and heterosexual men. Sixty-nine patients were also human immunodeficiency virus (HIV) positive, with detectable viral loads at the moment of LGV diagnosis, suggesting a high-risk of co-transmission. In fact, in four patients the diagnosis of HIV was simultaneous with LGV infection. The conventional treatment with doxycycline was prescribed in 75 patients, although in three patients the treatment failed. The sequencing of the ompA gene permitted identification of two independent transmission nodes. One constituted by 25 sequences identical to the L2b variant, and a second node including 37 sequences identical to L2. This epidemiological situation characterized by the co-circulation of two LGV variants has not been previously described, reinforcing the need for screening and genotyping of LGV strains

Magnetic ground state of the one-dimensional ferromagnetic chain compounds M(NCS)2(thiourea)2 (M=Ni,Co)

The magnetic properties of the two isostructural molecule-based magnets—Ni(NCS)2(thiourea)2, S = 1 [thiourea = SC(NH2 )2] and Co(NCS)2 (thiourea)2, S = 3/2—are characterized using several techniques in order to rationalize their relationship with structural parameters and to ascertain magnetic changes caused by substitution of the spin. Zero-field heat capacity and muon-spin relaxation measurements reveal low-temperature long-range ordering in both compounds, in addition to Ising-like (D < 0) single-ion anisotropy (DCo ∼ −100 K, DNi ∼ −10 K). Crystal and electronic structure, combined with dc-field magnetometry, affirm highly quasi-onedimensional behavior, with ferromagnetic intrachain exchange interactions JCo ≈ +4 K and JNi ∼ +100 K and weak antiferromagnetic interchain exchange, on the order of J ∼ −0.1 K. Electron charge- and spin-density mapping reveals through-space exchange as a mechanism to explain the large discrepancy in J-values despite, from a structural perspective, the highly similar exchange pathways in both materials. Both species can be compared to the similar compounds MCl2(thiourea)4, M = Ni(II) (DTN) and Co(II) (DTC), where DTN is known to harbor two magnetic-field-induced quantum critical points. Direct comparison of DTN and DTC with the compounds studied here shows that substituting the halide Cl− ion for the NCS− ion results in a dramatic change in both the structural and magnetic properties

Planck-LFI: Design and Performance of the 4 Kelvin Reference Load Unit

The LFI radiometers use a pseudo-correlation design where the signal from the sky is continuously compared with a stable reference signal, provided by a cryogenic reference load system. The reference unit is composed by small pyramidal horns, one for each radiometer, 22 in total, facing small absorbing targets, made of a commercial resin ECCOSORB CR (TM), cooled to approximately 4.5 K. Horns and targets are separated by a small gap to allow thermal decoupling. Target and horn design is optimized for each of the LFI bands, centered at 70, 44 and 30 GHz. Pyramidal horns are either machined inside the radiometer 20K module or connected via external electro-formed bended waveguides. The requirement of high stability of the reference signal imposed a careful design for the radiometric and thermal properties of the loads. Materials used for the manufacturing have been characterized for thermal, RF and mechanical properties. We describe in this paper the design and the performance of the reference system.Comment: This is an author-created, un-copyedited version of an article accepted for publication in JINST. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The definitive publisher authenticated version is available online at [10.1088/1748-0221/4/12/T12006]. 14 pages, 34 figure

Gibbs distribution analysis of temporal correlations structure in retina ganglion cells

We present a method to estimate Gibbs distributions with \textit{spatio-temporal} constraints on spike trains statistics. We apply this method to spike trains recorded from ganglion cells of the salamander retina, in response to natural movies. Our analysis, restricted to a few neurons, performs more accurately than pairwise synchronization models (Ising) or the 1-time step Markov models (\cite{marre-boustani-etal:09}) to describe the statistics of spatio-temporal spike patterns and emphasizes the role of higher order spatio-temporal interactions.Comment: To appear in J. Physiol. Pari

Boxy/peanut/X bulges, barlenses and the thick part of galactic bars: What are they and how did they form?

Bars have a complex three-dimensional shape. In particular their inner part is vertically much thicker than the parts further out. Viewed edge-on, the thick part of the bar is what is commonly known as a boxy-, peanut- or X- bulge and viewed face-on it is referred to as a barlens. These components are due to disc and bar instabilities and are composed of disc material. I review here their formation, evolution and dynamics, using simulations, orbital structure theory and comparisons to observations.Comment: 21 pages, 7 figures, invited review to appear in "Galactic Bulges", E. Laurikainen, R. Peletier, D. Gadotti, (eds.), Springe

The natural capital accounting opportunity: Let s really do the numbers

This work was conducted as a part of the “Accounting for U.S. Ecosystem Services at National and Subnational Scales” working group supported by the National Socio-Environmental Synthesis Center under funding received from the National Science Foundation (grant no. DBI-1052875) and the US Geological Survey John Wesley Powell Center for Analysis and Synthesis (grant no. GX16EW00ECSV00)