Muscle Fatigue at the End of a Maximal Oxygen Consumption Test

Fatigue is a task dependent multifactorial phenomenon, and the most common tool to analyze it is the VO2max test. The purpose of this study was to investigate if muscle is exhaustively taxed at the end of a VO2max test. This was based on data from sEMG, heart rate, and force applied to the pedals during and immediately after a VO2max test compared to an intense anaerobic test. Methods. 12 male participants (mean ± SD age = 28.09 ± 6.55 years, height = 176.7 ± 2.97 cm, weight = 73.31 ± 8.44 kg, and VO2max = 60.93 ± 9.75 mL/kg/min) were recruited for the study to perform a VO2max test and an intense anaerobic test (the control), to compare the level of muscle fatigue at the end of the VO2max test. Following a load determining VO2max cycling trial, exercise trials were performed in a randomized order separated by at least seven days. For the VO2max tests, the participants performed a graded exercise protocol at 60 rpm on a mechanically braked cycle ergometer; the power output was set according to each subjects fitness level to complete the test in 8 to 10 minutes. The intense anaerobic test consisted of cycling on the same ergometer at 60 rpm and 100% of the initial Wattspeak. In both tests, the participants were encouraged to pedal constantly until reaching volitional exhaustion. The root mean square (RMS), mean power frequency (MPF), and median frequency (MF) were extracted and normalized using the maximal voluntary contraction (MVC) from the selected sEMG samples. MATLAB was used in order to observe the tendencies over time for the left and right rectus femoris, vastus medialis and vastus lateralis. Force production applied to the pedals was measured using four flexiforce load sensors (Teskan, Inc. Boston, MA. USA) installed within each pedal. Heart rate (HR) was monitored during the tests via a commercial clinical electrocardiogram (GE Medical Systems, Milwaukee, WI, USA). Bilateral MVCs were measured before and immediately after each test with the knee positioned at 60 degrees of flexion prior to the MVCs. A paired t-test was used to compare means from sEMG, heart rate and force production pre-test and post-test between both group trials with significance set at p\u3c0.05. Results. The percentage change in mean sEMG from baseline MVC values was significantly larger for the intense anaerobic tests at the end compared to the VO2max test for two of the six muscles monitored. For the left rectus femoris the remaining percentage of baseline MVC was 84.53 ± 15.01% and 89.9 ± 16.74, respectively, for the intense anaerobic and the VO2max trial; F(1,5)= 8.124, p = 0.036. Also, a significantly lower remaining percentage of baseline MVC was found for the anaerobic intense trial compared to the VO2max test for right vastus lateralis, 81.92 ± 8.0% and 93.12 ± 4.21% respectively; F(1,6)= 11.47, p = 0.015. There was a significant remaining difference in the median sEMG frequency for three of the six muscles monitored. A lower remaining percentage was found for the intense anaerobic test for the right vastus lateralis than for the VO2max test (80.54 ± 13.1% and 93.46 ± 8.78% respectively; F(1,6)= 7.58, p = 0.03. respectively). Similarly, the right rectus femoris showed a smaller remaining percentage for the anaerobic test than for the VO2max (82.5 ± 10.51% and 92.9 ± 8.85%; F(1,5)= 12.60, p = 0.016). The only muscle that showed a smaller remaining percentage for the VO2max compared to the intense anaerobic test was the left vastus medialis (79.39 ± 11.26% and 88.28 ± 9.6%, respectively; F(1,6)= 8.51, p = 0.027). No statistically significant differences were found for the post-test heart rate, force production and MVC. Conclusion. Mean and median frequency sEMG data provided the best way to analyze muscle fatigue at the end of a maximal test. From these signals muscle fatigue at the end of a VO2max test seems not to be maximal; there is a reserve of muscle fiber recruitment mainly from the slow-twitch fiber type.\u2

Pixel design and evaluation in CMOS image sensor technology

A chip designed in a 0.18 μm CMOS Image Sensor Technology (CIS) is presented which incorporates different pixel design alternatives for Active Pixel Sensor (APS). CIS technology improves characteristics such as sensitivity, dark current and noise, that are strongly layout dependent. This chip includes a set of pixel architectures where different parameters have been modified: layout of active diffusion, threshold voltage of the source follower transistor and the use of microlenses. Besides, structures to study the influence of crosstalk between pixels have been incorporated

Live demonstration: Real-time high dynamic range video acquisition using in-pixel adaptive content-aware tone mapping compression

This demonstration targets the acquisition of realtime video sequences involving High Dynamic Range (HDR) scenes. Adaptation to different illumination conditions while preserving contrast is achieved by using a sensor chip, which implements an adaptive content-aware tone mapping compression algorithm by using in-pixel circuitry. Its response gets adapted to changing illumination conditions by using at each frame a statistical estimation of the light distribution, which is derived from the HDR histogram calculated at the previous frame. This method allows adaptive HDR video, while capable to capture very large DR scenes including moving objects.Office of Naval Research (USA) N000141410355Ministerio de Economía y Competitividad IPT-2011-1625-430000Junta de Andalucía TIC 2338-201

3D tissue formation : the kinetics of human mesenchymal stem cells

The main thesis in this book proposes that physical phenomena underlies the formation of three-dimensional (3D) tissue. In this thesis, tissue regeneration with mesenchymal stem cells was studied through the law of conservation of mass. MSCs proliferation and 3D tissue formation were explored from 2D to 3D conditions. The kinetics of proliferation was the unifying principle to compare and analyze the behavior of human MSCs (hMSCs) through the quantification of the movement or conversion of mass during proliferation. This thesis focuses on the kinetics of proliferation of hMSCs under two physical phenomena (Diffusive mass transport and shear stress). hMSCs were shown to have different kinetics when cultured at different seeding densities (Chapter 1). On the other hand, a kinetic pattern was maintained under both diffusive mass transport and shear stress (Chapter 2). The importance of these two chapters lies in identifying the metabolic processes during hMSCs proliferation that are in/dependent of physical parameters. The shear stress characterization of 3D scaffolds provided Darcian permeability constants to include in the design and analysis of 3D scaffolds. Based on the findings of chapters 1- 3, the main purpose of chapter 4 was to explore 3D tissue formation with hMSCs under diffusive mass transport (static) and shear stress (bioreactor). These results showed that 3D tissue formation correlates with concentration gradients that were estimated through computational fluid dynamics. The kinetics of proliferation of hMSCs under both 2D and 3D showed that hMSCs proliferate slower in 3D than in 2D, but achieve a higher degree of organization in 3D. The practical application of 3D tissue formation by hMSCs was further explored in chapter 5 towards the development of an in vivo high throughput screening (HTS) system. This HTS system offers the possibility to screen multiple conditions in animal models, thereby significantly decreasing the costs and lives sacrificed in animal experiments

Direccionamiento estratégico a la asociación de paneleros de Belén de Umbría. (ASOPABel)

El trabajo de grado consta en diseño de una propuesta de mejoramiento administrativo a la asociación de paneleros del municipio de Belén de Umbría Risaralda (Asopabel). Para lograr esto, se tomó como base un “direccionamiento estratégico”. Fue necesario la utilización de herramientas de análisis como la matriz de oportunidades y amenazas del medio (poam) , un censo, entrevistas, visitas y de herramientas de administración. para hacer una evaluación general de dicho direccionamiento estratégico en esta asociación que permitiera generar estrategias encaminadas a potenciar una estructura organizacional . Es importante hacer claridad que para esto se tuvo como pilar fundamental la construcción teórica que se tiene dentro del trabajo de grado

Portal WEB para la gestión de laboratorios

Investigación TecnológicaPartiendo de una visión innovadora en la cual se pretende renovar el sistema actual que tiene la universidad Católica de Colombia sobre el control de los instrumentos de laboratorio, se presenta un prototipo de software donde todos los usuarios (en este caso Auxiliares de laboratorio), se puedan conectar y tener acceso a la base de datos tanto de los instrumentos como de los estudiantes, de esta forma gestionar el despacho de instrumentos a los estudiantes, así optimizando recursos y tiempo, además de dar un toque de vanguardia tecnológica a los laboratorios de ingeniería, con la implementación de software y lectores de código de barras. La propuesta de software a implementar, es un portal web donde los usuarios de laboratorio pueden ingresar por medio de un nombre de usuario y una contraseña, para realizar los despachos de instrumentos a los estudiantes, y con la ayuda de un lector de código de barras se obtiene el código del alumno como el de los instrumentos involucrados.PregradoIngeniero Electrónic

Missed opportunities for HIV diagnosis among incarcerated people in the Federal District, Brasilia, Brazil

Objective. Evaluate the pattern of contact with the healthcare system, including prison health facilities, and HIV testing. Method. This was a quantitative case-control study of HIV infected and uninfected incarcerated people serving time in 2019 in the Federal District, matched by age. Results. There was no difference in the pattern of contact with the healthcare system or the pattern of testing between HIV-infected and uninfected incarcerated people. Most of the infected patients were diagnosed in the prison environment and had early infections, demonstrating the effectiveness of screening in this scenario. Conclusion: The pattern of contact with the healthcare system among the individuals in this study probably reflects that of young men in general, i.e., less contact with primary care outpatient services and trauma as the main reason for contact in emergency departments. Objetivo. Evaluar el patrón de contacto con el sistema sanitario, incluidos los centros sanitarios penitenciarios, y las pruebas del VIH. Método. Estudio cuantitativo de casos y controles de personas infectadas y no infectadas por el VIH que cumplían condena en 2019 en el Distrito Federal, emparejadas por edad. Resultados. No hubo diferencias en el patrón de contacto con el sistema de salud ni en el patrón de realización de pruebas entre personas encarceladas infectadas y no infectadas por VIH. La mayoría de los pacientes infectados fueron diagnosticados en el medio penitenciario y presentaron infecciones precoces, lo que demuestra la eficacia del cribado en este escenario. Conclusiones. El patrón de contacto con el sistema sanitario entre los individuos de este estudio probablemente refleja el de los hombres jóvenes en general, es decir, menor contacto con los servicios ambulatorios de atención primaria y traumatismos como principal motivo de contacto en los servicios de urgencias. Objetivo. O estudo avaliou o padrão de contato com o sistema de saúde e de testagem para HIV, incluindo as unidades de saúde prisionais.  Métodos. Trata-se de estudo quantitativo de caso-controle em detentos que cumpriam pena em 2019 no Distrito Federal, pareados por idade. Resultados. Não houve diferença no padrão de contato com o sistema de saúde e padrão de oferta de testagem entre detentos infectados ou não com HIV. A maior parte dos infectados teve o diagnóstico realizado no ambiente prisional e de maneira precoce, evidenciando efetividade do rastreamento nesse cenário. Conclusão. O padrão de contato com o sistema de saúde dos indivíduos neste estudo reflete provavelmente o de homens jovens como um todo: pouco contato com serviços ambulatoriais de atenção primária e trauma como principal motivo de contato, em prontos-socorros. 

Épica en el arte : el caso de la canción de autor

Existe el concepto de épica que todo el mundo conoce más o menos: las hazañas heroicas de una persona individual. Pero debajo de él subyacen otras concepciones, como es la lucha cotidiana de héroes anónimos que se enfrentan cada día a su existencia, y que en cuanto dichas luchas tienen rasgos comunes entre personas parecidas, se convierte en una epopeya; también es concebible como la lucha histórica de un grupo marinado por el reconocimiento de sus derechos y su supervivencia. El arte se ha ocupado de estas otras nociones, especialmentea partir del siglo XIX, con el surgimiento de lo social en él, tratando de dotar a esas personas de dignidad histórica. En estas páginas, examinaremos el caso especial de la canción de autor surgida entre los años 60 y 70. There is the concept of epic known by the most: the heroic feats of one individual person. But under that, other conceptions underlies, as the dailyfight of anonymous heroes who face to their existence every day, and, as those struggles have some common characteristics between similar people, itturns into epos; also is conceivable as the historic struggle of emarginated group for the recognition of their rights and survivor. Art has looked after these notions, specially after XIX century, with the rising of the social matter on it, trying to give historical dignity to those people. Along these pages, we shall examine the special case of the Spanish protest song, rising between the 60s and the 70s

Early-onset neonatal sepsis and the implementation of group B streptococcus prophylaxis in a Brazilian maternity hospital : a descriptive study

Objectives: to describe early-onset neonatal sepsis (EOS) epidemiology in a public maternity hospital in Brasilia, Brazil. Methods: we defined EOS as a positive blood culture result obtained from infants aged ≤72 hours of life plus treatment with antibiotic therapy for ≥5 days. Incidence was calculated based on the number of cases and total live births (LB). This is a descriptive study comparing the period of 2012–2013 with the period of 2014–September 2015, before and after implementation of antibiotic prophylaxis during labor for group B streptococcus (GBS) prevention, respectively. Results: overall, 36 infants developed EOS among 21,219 LB (1.7 cases per 1000 LB) and 16 died (case fatality rate of 44%). From 2014, 305 vaginal-rectal swabs were collected from high-risk women and 74 (24%) turned out positive for GBS. After implementation of GBS prevention guidelines, no new cases of GBS were detected, and the EOS incidence was reduced from 1.9 (95% CI 1.3–2.8) to 1.3 (95% CI 0.7–2.3) cases per 1000 LB from 2012–2013 to 2014–September 2015 (p = 0.32). Conclusions: although the reduction of EOS incidence was not significant, GBS colonization among pregnant women was high, no cases of neonatal GBS have occurred after implementation of prevention guidelines

El CFMA “formación en la minería bien hecha”

El CFMA posee alianzas y convenios con las principales empresas mineras de la región y el país, desarrollando programas de formación y proyectos de investigación, innovación y desarrollo de la mano de: Grupo Mineros S.A., Operadora Minera S.A.S., EMIJOM S.A.S., EMINCUT S.A.S., Red Eagle Mining de Colombia S.A. y Anglo-Gold Ashanti Colombia S.A.