5,742 research outputs found

    Effects of different post-activation potentiation warm-ups on repeated sprint ability in soccer players from different competitive levels

    Get PDF
    This study aimed to compare the effects of a traditional warm-up with two post-activation potentiation (PAP) warm-up strategies on the repeated sprint ability (RSA) of soccer players from national (NL) and regional (RL) competitive levels. Sixteen young players (NL, n = 8, age = 20.7 +/- 1.4 y, body mass = 68.5 +/- 7.0 kg, body height = 177.4 +/- 5.2 cm; RL, n = 8, age = 20.8 +/- 1.0 y, body mass = 68.7 +/- 4.0 kg, body height = 176.6 +/- 5.6 cm) were recruited to complete a traditional warm-up (CONTROL), a PAP warm-up incorporating squats with a load (similar to 60% 1RM) that allowed a high speed (1 m/s) of movement and a high number of repetitions (PAP-1), and a PAP warm-up with a load (similar to 90% 1RM) that allowed a moderate speed (0.5 m/s) of movement and a reduced number of repetitions (PAP-0.5). A RSA test (six 20-m sprints with 20 s of recovery) was performed 5 min after the PAP warm-up to assess the effects of the different protocols on the fastest sprint (RSAb) and the mean time of all sprints (RSAm). A meaningful improvement of RSA performance was observed with PAP-0.5, attaining a large effect on NL (RSAb, ES = -1.5; RSAm, ES = -1.3) and only a small effect on RL athletes (RSAb and RSAm, ES = -0.2). Moreover, when each RSA sprint performance was compared between NL and RL players, after PAP-0.5 greater performance for all sprints was observed in the NL players. Therefore, adding a heavy strength-based conditioning exercise during the warm-up prior to a RSA test may induce significant performance improvements in NL, but only small effects in RL players

    Human case of swine influenza A (H1N1), Aragon, Spain, November 2008

    Get PDF
    A human case of swine influenza A (H1N1) in a 50-year-old woman from a village near Teruel (Aragon, in the north-east of Spain), with a population of about 200 inhabitants, has been reported in November 2008.S

    RNA-SEQ of fv-induced erythroleukemia cells suggests a role of wasp.

    Get PDF
    The goal of research is analyze the molecular function of was in progenitors of the erythoid linage and its role in reprogramming celular differentiation in erythroleukemia cells.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

    Associations between overall, healthful, and unhealthful low-fat dietary patterns and breast cancer risk in a Mediterranean cohort: The SUN project

    Get PDF
    Objectives: Dietary patterns may have a greater influence on human health than individual foods or nutrients, and they are also of substantial interest in the field of breast cancer prevention. Beyond the adequate balance of macronutrients, evidence indicates that the quality of macronutrient sources may play an important role in health outcomes. We sought to examine the relationship between healthful and unhealthful low-fat dietary patterns in relation to breast cancer. Methods: We used observational data from a Mediterranean cohort study (the Seguimiento Universidad de Navarra project). We prospectively followed 10 930 middle-aged women initially free of breast cancer during a median follow-up of 12.1 y. We calculated an overall, an unhealthful, and a healthful low-fat diet score, based on a previously validated 136-item food frequency questionnaire and grouped participants into ter- tiles. Incident breast cancer—overall and stratified by menopausal status—was the primary outcome. It was self-reported by participants and confirmed based on medical reports or consultation of the National Death Index. We used multivariable Cox regression models adjusted for potential confounders. Results: During 123 297 person-years of follow-up, 150 cases of incident breast cancer were confirmed. No signifi- cant associations were observed for overall or premenopausal breast cancer. For postmenopausal women, we observed a significant association for moderate adherence to the unhealthful low-fat dietary score and postmeno- pausal breast cancer (comparing tertile 2 to tertile 1; hazard ratio = 2.18; 95% confidence interval, 1.15 4.13). Conclusions: In conclusion, no clear associations were observed, although more research is needed to address the association between an unhealthful dietary pattern and postmenopausal breast cancer risk

    Tidal Energy Round Robin Tests: A Comparison of Flow Measurements and Turbine Loading

    Get PDF
    A Round Robin Tests program is being undertaken within the EC MaRINET2 initiative. This programme studies the used facility influence can have on the performance evaluation of a horizontal axis tidal turbine prototype when it is operated under wave and current conditions. In this paper, we present the design of experiments that is used throughout the work programme and the results related to the flow characterisation obtained at the Ifremer wave and current circulating tank, the Cnr-Inm wave towing tank and the ocean research facility FloWave. These facilities have been identified to provide adequate geometric conditions to accommodate a 0.724 m diameter turbine operating at flow velocities of 0.8 and 1.0 m/s. The set-up is replicated in each of the facilities with exemption of the amount of flow measuring instruments. Intrinsic differences in creating wave and currents between facilities are found. Flow velocities are up to 10% higher than the nominal values and wave amplitudes higher than the target values by up to a factor of 2. These discrepancies are related to the flow and wave generation methods used at each facility. When the flow velocity is measured besides the rotor, the velocity presents an increase of 8% compared to the upstream measurements

    Analysis of the effects of control strategies and wave climates on the loading and performance of a laboratory scale horizontal axis tidal turbine

    Get PDF
    To understand the influence of complex hydrodynamic loads on tidal turbines, laboratory testing is necessary as a first approach. Previous laboratory work undertaken gave an indication that the use of speed control strategies may disguise the associated loading range that a turbine may be subjected to when this is operated with a variable speed control strategy. However, the preceding work was undertaken in a highly controlled environment without the influence of turbulent flows. The focus of this paper is directed towards the study of wave-induced loads on tidal turbines when these are controlled using two strategies and the impact that these parameters have on the turbine's performance when this is operated in a recirculating flume. Laboratory tests were undertaken with a 0.9 m diameter horizontal axis tidal turbine subjected to combined wave and current conditions with both regular and irregular waves. Constant speed and constant torque control strategies have been considered, for which rotor thrust, torque and blade root bending moment have been measured. Results show that similar to previous studies, average loads and power capture values remain unchanged between control strategies and the superposition of waves to the current. However, signal fluctuations are 2 to 3 times higher for torque control than for constant speed control strategy. A phase difference between the periodic signals of the turbine thrust and the incoming waves was also identified, in this case, the phase variation was lower when using torque than speed control. This work thus demonstrates the implication of studying strategies to control a marine converter from early stages of development

    Animal Models of Rheumatoid Arthritis

    Get PDF
    Autoimmunity is a condition in which the host organizes an immune response against its own antigens. Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology, characterized by the presence of chronic inflammatory infiltrates, the development of destructive arthropathy, bone erosion, and degradation of the articular cartilage and subchondral bone. There is currently no treatment that resolves the disease, only the use of palliatives, and not all patients respond to pharmacologic therapy. According to RA multifactorial origin, several in vivo models have been used to evaluate its pathophysiology as well as to identify the usefulness of biomarkers to predict, to diagnose, or to evaluate the prognosis of the disease. This chapter focuses on the most common in vivo models used for the study of RA, including those related with genetic, immunological, hormonal, and environmental interactions. Similarly, the potential of these models to understand RA pathogenesis and to test preventive and therapeutic strategies of autoimmune disorder is also highlighted. In conclusion, of all the animal models discussed, the CIA model could be considered the most successful by generating arthritis using type II collagen and adjuvants and evaluating therapeutic compounds both intra-articularly and systemically

    Biological Activity and Implications of the Metalloproteinases in Diabetic Foot Ulcers

    Get PDF
    Inadequate metabolic control predisposes diabetic patient to a series of complications on account of diabetes mellitus (DM). Among the most common complications of DM is neuropathy, which causes microvascular damage by hyperglycemia in the lower extremities which arrives characterized by a delayed closing. The global prevalence of diabetic neuropathy (DN) was 66% of people with diabetes in 2015, representing the principal cause of total or partial lower extremities amputation, with 22.6% of the patients with DN. Matrix metalloproteinases (MMPs) are involved in healing. The function that these mainly play is the degradation during inflammation that has as consequence the elimination of the extracellular matrix (ECM), the disintegration of the capillary membrane to give way to angiogenesis and cellular migration for the remodeling of damaged tissue. The imbalance in MMPs may increase the chronicity of a wound, what leads to chronic foot ulcers and amputation. This chapter focuses on the role of MMPs in diabetic wound healing

    Performance analysis of model-scale tidal stream turbines situated in different array configurations

    Get PDF
    Tidal stream technology is a promising source of renewable energy which is expected to contribute to the global energy mix by 2050. The technology is currently still in its infancy and the road to commercialisation relies on extensive research and development that will improve the operability of tidal devices and increase the efficiency of power generation. This report presents the results of an experimental study into the performance of scale model horizontal axis tidal stream turbines placed in different array configurations.Optimising an array configuration can maximise power extraction which is essential in driving reductions in the levelised cost of energy associated with tidal power. In the experimental investigation presented, three scale model turbines were placed in four different configurations. The flow data and turbine performance data were analysed to determine which array generated the most favourable results. The four array layouts were all setup with two upstream devices with a single downstream device. These devices were set in a delta shape with tests repeated with differing lateral separation between upstream devices and longitudinal separation between the front row and the single downstream device. A single array configuration with the downstream device 7.8D downstream of the front row of turbines was tested along with three compact array cases with the downstream device was set at 3.2D downstream of the front row of devices. All three devices were operated at a constant rotational speed for a given test and array configuration as facilitated by the permanent magnet synchronous machine operating under servo control. To achieve a range of operating conditions for each array configuration, a range of experiments were undertaken at each layout with the downstream device operating at differing rotational velocities
    corecore