916 resultados para Anaerobic fitness


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Sie wollen fitter werden, etwas für Ihre Gesundheit tun? Dieser Beobachter-Ratgeber unterstützt Sie dabei, Freude am Sport zu entwickeln. Die Autorinnen – zwei begeisterte Sportlerinnen – zeigen Ihnen, wie Sie von der Idee zum Tun gelangen. Wie Sie Ihren Willen stärken, sich klare Ziele setzen und diese auch erreichen. Mithilfe von Fragebogen und Aufgabenboxen setzen Sie die Ratschläge konkret um und finden Ihren persönlichen Zugang zu mehr Bewegung. Besonders hilfreich sind die Beschreibungen unterschiedlicher Indoor- und Outdoorsportarten. So finden Sie den Weg zu einem aktiven Lebensstil. Denn das ist die wichtigste Botschaft dieses Buches: Sport und Bewegung tun gut und können richtig Spass machen.

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Positive-stranded viruses synthesize their RNA in membrane-bound organelles, but it is not clear how this benefits the virus or the host. For coronaviruses, these organelles take the form of double-membrane vesicles (DMVs) interconnected by a convoluted membrane network. We used electron microscopy to identify murine coronaviruses with mutations in nsp3 and nsp14 that replicated normally while producing only half the normal amount of DMVs under low-temperature growth conditions. Viruses with mutations in nsp5 and nsp16 produced small DMVs but also replicated normally. Quantitative reverse transcriptase PCR (RT-PCR) confirmed that the most strongly affected of these, the nsp3 mutant, produced more viral RNA than wild-type virus. Competitive growth assays were carried out in both continuous and primary cells to better understand the contribution of DMVs to viral fitness. Surprisingly, several viruses that produced fewer or smaller DMVs showed a higher fitness than wild-type virus at the reduced temperature, suggesting that larger and more numerous DMVs do not necessarily confer a competitive advantage in primary or continuous cell culture. For the first time, this directly demonstrates that replication and organelle formation may be, at least in part, studied separately during infection with positive-stranded RNA virus. IMPORTANCE The viruses that cause severe acute respiratory syndrome (SARS), poliomyelitis, and hepatitis C all replicate in double-membrane vesicles (DMVs). The big question about DMVs is why they exist in the first place. In this study, we looked at thousands of infected cells and identified two coronavirus mutants that made half as many organelles as normal and two others that made typical numbers but smaller organelles. Despite differences in DMV size and number, all four mutants replicated as efficiently as wild-type virus. To better understand the relative importance of replicative organelles, we carried out competitive fitness experiments. None of these viruses was found to be significantly less fit than wild-type, and two were actually fitter in tests in two kinds of cells. This suggests that viruses have evolved to have tremendous plasticity in the ability to form membrane-associated replication complexes and that large and numerous DMVs are not exclusively associated with efficient coronavirus replication.

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Two highly efficient (K2CO3/sludge carbon and ZnCl2/sludge carbon) solids were prepared by chemical addition following carbonization at 800 °C and were tested for anaerobic reduction of tartrazine dye in a continuous upflow packed-bed biological reactor, and their performance was compared to that of commercial activated carbon (CAC). The chemical and structural information of the solids was subjected to various characterizations in order to understand the mechanism for anaerobic decolorization, and efficiency for SBCZN800 and SBCPC800 materials was 87% and 74%, respectively, at a short space time (τ) of 2.0 min. A first-order kinetic model fitted the experimental points and kinetic constants of 0.40, 0.92 and 1.46 min(-1) were obtained for SBCZN800, SBCPC800 and CAC, respectively. The experimental results revealed that performance of solids in the anaerobic reduction of tartrazine dye can depend on several factors including chemical agents, carbonization, microbial population, chemical groups and surface chemistry. The Langmuir and Freundlich models are successfully described in the batch adsorption data. Based on these observations, a cost-effective sludge-based catalyst can be produced from harmful sewage sludge for the treatment of industrial effluents.

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This work presents the preliminary study of new carbonaceous materials (CMs) obtained from exhausted sludge, their use in the heterogeneous anaerobic process of biodecolorization of azo dyes and the comparison of their performance with one commercial active carbon. The preparation of carbonaceous materials was conducted through chemical activation and carbonization. Chemical activation was carried out through impregnation of sludge-exhausted materials with ZnCl2 and the activation by means of carbonization at different temperatures (400, 600 and 800°C). Their physicochemical and surface characteristics were also investigated. Sludge based carbonaceous (SBC) materials SBC400, SBC600 and SBC800 present values of 13.0, 111.3 and 202.0m(2)/g of surface area. Biodecolorization levels of 76% were achieved for SBC600 and 86% for SBC800 at space time (τ) of 1.0min, similar to that obtained with commercial activated carbons in the continuous anaerobic up-flow packed bed reactor (UPBR). The experimental data fit well to the first order kinetic model and equilibrium data are well represented by the Langmuir isotherm model. Carbonaceous materials show high level of biodecolorization even at very short space times. Results indicate that carbonaceous materials prepared from sludge-exhausted materials have outstanding textural properties and significant degradation capacity for treating textile effluents.

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Metazoans have evolved ways to engage only the most appropriate cells for long-term tissue development and homeostasis. In many cases, competitive interactions have been shown to guide such cell selection events. In Drosophila, a process termed cell competition eliminates slow proliferating cells from growing epithelia. Recent studies show that cell competition is conserved in mammals with crucial functions like the elimination of suboptimal stem cells from the early embryo and the replacement of old T-cell progenitors in the thymus to prevent tumor formation. Moreover, new data in Drosophila has revealed that fitness indicator proteins, required for cell competition, are also involved in the culling of retinal neurons suggesting that 'fitness fingerprints' may play a general role in cell selection.

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In this study, we tested whether a standardized epigallocatechin-3-gallate (EGCG) rich green tea extract (comprising > 90% EGCG) affects fitness and lifespan as well as parameters of glucose metabolism and energy homeostasis in the fruit fly, Drosophila melanogaster. Following the application of the green tea extract a significant increase in the mean lifespan (+ 3.3 days) and the 50% survival (+ 4.3 days) as well as improved fitness was detected. These effects went along an increased expression of Spargel, the homolog of mammalian PGC1α, which has been reported to affect lifespan in flies. Intriguingly, in flies, treatment with the green tea extract decreased glucose concentrations, which were accompanied by an inhibition of α-amylase and α-glucosidase activity. Computational docking analysis proved the potential of EGCG to dock into the substrate binding pocket of α-amylase and to a greater extent into α-glucosidase. Furthermore, we demonstrate that EGCG downregulates insulin-like peptide 5 and phosphoenolpyruvate carboxykinase, major regulators of glucose metabolism, as well as the Drosophila homolog of leptin, unpaired 2. We propose that a decrease in glucose metabolism in connection with an upregulated expression of Spargel contribute to the better fitness and the extended lifespan in EGCG-treated flies.

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Plants produce large amounts of secondary metabolites in their shoots and roots and store them in specialized secretory structures. Although secondary metabolites and their secretory structures are commonly assumed to have a defensive function, evidence that they benefit plant fitness under herbivore attack is scarce, especially below ground. Here, we tested whether latex secondary metabolites produced by the common dandelion (Taraxacum officinale agg.) decrease the performance of its major native insect root herbivore, the larvae of the common cockchafer (Melolontha melolontha), and benefit plant vegetative and reproductive fitness under M. melolontha attack. Across 17 T. officinale genotypes screened by gas and liquid chromatography, latex concentrations of the sesquiterpene lactone taraxinic acid β-D-glucopyranosyl ester (TA-G) were negatively associated with M. melolontha larval growth. Adding purified TA-G to artificial diet at ecologically relevant concentrations reduced larval feeding. Silencing the germacrene A synthase ToGAS1, an enzyme that was identified to catalyze the first committed step of TA-G biosynthesis, resulted in a 90% reduction of TA-G levels and a pronounced increase in M. melolontha feeding. Transgenic, TA-G-deficient lines were preferred by M. melolontha and suffered three times more root biomass reduction than control lines. In a common garden experiment involving over 2,000 T. officinale individuals belonging to 17 different genotypes, high TA-G concentrations were associated with the maintenance of high vegetative and reproductive fitness under M. melolontha attack. Taken together, our study demonstrates that a latex secondary metabolite benefits plants under herbivore attack, a result that provides a mechanistic framework for root herbivore driven natural selection and evolution of plant defenses below ground.

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Firefighting is widely known to be one of the most physically demanding civilian occupations. A subset of this is Industrial Firefighting, which places similarly high physical demands on Industrial Firefighters. Although there are some studies on community firefighters, literature is scant on Industrial Firefighters and their physical fitness. ^ A cross-sectional study of Industrial Firefighters in Petrochemical companies in Texas was carried out in 1996–98 to assess their physical fitness and to develop a set of physical agility criteria useful in their selection and ongoing fitness for duty evaluations. ^ A physical agility criteria and a fitness scorecard was developed based on seven parameters (resting heart rate, diastolic blood pressure, aerobic capacity, muscle strength, muscle endurance, trunk flexibility and total body fat) of musculoskeletal and cardiorespiratory fitness. Each indicator received a minimum of 0 to a maximum of 20 points, based on individual performance. Therefore a minimum and maximum achievable score for the entire battery of tests was 0 and 140 respectively. Of the 111 study subjects, 5 (4.5%) were far above average, 31 (28%) above average, 46 (41.5 %) average, 29 (26%) below average and 0 (0%) far below average as deemed by the physical fitness scorecard. The mean score was 77 (±23) with a minimum and maximum score of 35 and 135 respectively. ^ Following univariate analysis an exploratory factor analysis to group variables and to assess the overall role of constituent variables in total fitness of a firefighter was developed. This was followed by a stepwise linear regression analysis using aerobic capacity as a dependent variable. ^ Finally, a graded implementation strategy was devised, such that all existing Industrial Firefighters would have an opportunity to improve or maintain their physical fitness at or above average level as deemed by the fitness scorecard. ^

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Numerous genes expressed in placenta or testis localize to the X-chromosome. Both tissues undergo specialized X-chromosome inactivation (imprinted paternal inactivation in placenta and MSCI in testicular germ cells). When the X-chromosome is duplicated or improperly inactivated, defects in placentation, growth and spermatogenesis are noted, suggesting tight control of X-chromosome gene dosage is important for reproduction. ^ Esx1 is a mouse homeobox gene on the X-chromosome with expression limited to extraembryonic tissues and testicular germ cells. Here, we examine the effects of increased and decreased Esx1 dosage on placental and testicular development, the role of genetic background on Esx1 function and characterize the human orthologue of Esx1. ^ Previously, by targeted deletion, Esx1 was shown to be an X-chromosome imprinted regulator of placental development and fetal growth. We show C57Bl6-congenic Esx1 mutants display a more severe phenotype with decreased viability and that the 129 genetic background contains dominant modifier genes that enhance Esx1 mutant survival. ^ Varying Esx1 dosage impacts testicular germ cell development. Esx1 hemizygous null mice are fertile, but we show their testes are two-thirds normal size. To examine the effect of increased Esx1 dosage, Esx1 BAC transgenic mice were generated. Increased Esx1 dosage results in dramatic deficits in testicular germ cell development, leading to sterility and testes one-fourth normal size. We show germ cell loss occurs through apoptosis, begins between postnatal day 6 and 10, and that no spermatocytes complete meiosis. Interestingly, increased Esx1 dosage in testes mimics germ cell loss seen in Klinefelter's (XXY) mice and humans and may represent a molecular mechanism for the infertility characteristic of this syndrome. ^ Esx1 dosage impacts reproductive fitness when maternally transmitted. Three transgenic founder females were unable to transmit the transgene to live offspring, but did produce transgenic pups at earlier stages. Additionally, one line of Esx1 BAC transgenic mice demonstrated decreased embryo size and fitness when the transgene is inherited compared to wild type littermates. ^ It is possible that Esx1 plays a role in human disorders of pregnancy, growth and spermatogenesis. Therefore, we cloned and characterized ESX1L (human Esx1), and show it is expressed in human testis and placenta. ^

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The U.S. Air Force, as with the other branches of military services, has physical fitness standards imposed on their personnel. These standards ensure a healthy and fit combat force. To meet these standards, Airmen have to maintain a certain level of physical activity in their lifestyle. Objective. This was a cross sectional (prevalence) study to evaluate the association of Airmen's self-reported physical activity and their performance in the Air Force Physical Fitness Assessment in 2007. Methods. The self-reported physical activity data were obtained from the Air Force Web Health Assessment (AF WEB HA), a web-based health questionnaire completed by the Airmen during their annual Preventive Health Assessment. The physical activity levels were categorized as having met or not having met the Centers for Disease Control and Prevention (CDC) and the American College of Sports Medicine (ACSM) physical activity recommendations. Physical Fitness scores were collected from the Air Force Fitness Management System (AFFMS), a repository of physical fitness test data. Results. There were 49,029 Airmen who answered the AF WEB HA in 2007 and also took their physical fitness test. 94.4% (n = 46,304) of Airmen met the recommended physical activity guidelines and 79.9% (n = 39,178) passed the fitness test. Total Airmen who both met the physical activity recommendations and passed the fitness test was 75.6% (n = 37,088). Airmen who did not meet the activity recommendations and also failed the fitness test totaled 635 or 1.3% of the study group. The Mantel-Haenszel Chi-Square analysis of the data on the activity levels and the physical fitness test relationship was the following χ2 = 18.52, df 1, and p = <0.0001. The Odds Ratio (OR) was 1.22 (95% CI 1.12, 1.34). Conclusion. The study determined that there was a positive association between Airmen's self-reported physical activity and their performance in the physical fitness assessment.^

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Background. Public schools are a key forum in the fight for child health because of the opportunities they present for physical activity and fitness surveillance. However, because schools are evaluated and funded on the basis of standardized academic performance rather than physical activity, empirical research evaluating the connections between fitness and academic performance is needed to justify curriculum allocations to physical activity. ^ Methods. Analyses were based on a convenience sample of 315,092 individually-matched standardized academic (TAKS™) and fitness (FITNESSGRAM®) test records collected by 13 Texas school districts under state mandates. We categorized each fitness result in quintiles by age and gender and used a mixed effects regression model to compare the academic performance of the top and bottom fitness groups for each fitness test and grade level combination. ^ Results. All fitness variables except BMI showed significant, positive associations with academic performance after sociodemographic covariate adjustments, with effect sizes ranging from 0.07 (95% CI: 0.05,0.08) in girls trunklift-TAKS reading to 0.34 (0.32,0.35) in boys cardiovascular-TAKS math. Cardiovascular fitness showed the largest inter-quintile difference in TAKS score (32-75 points), followed by curl-ups. After an additional adjustment for BMI and curl-ups, cardiovascular associations peaked in 8th-9 th grades (maximum inter-quintile difference 142 TAKS points; effect size 0.75 (0.69,0.82) for 8th grade girls math) and showed dose-response characteristics across quintiles (p<0.001 for both genders and outcomes). BMI analysis demonstrated limited, non-linear association with academic performance after adjustment for sociodemographic, cardiovascular fitness and curl-up variables. Low-BMI Hispanic high school boys showed significantly lower TAKS scores than the moderate (but not high) BMI group. High-BMI non-Hispanic white high school girls showed significantly lower scores than the moderate (but not low) BMI group. ^ Conclusions. In this study, fitness was strongly and significantly related to academic performance. Cardiovascular fitness showed a distinct dose-response association with academic performance independent of other sociodemographic and fitness variables. The association peaked in late middle to early high school. The independent association of BMI to academic performance was only found in two sub-groups and was non-linear, with both low and high BMI posing risk relative to moderate BMI but not to each other. In light of our findings, we recommend that policymakers consider PE mandates in middle-high school and require linkage of academic and fitness records to facilitate longitudinal surveillance. School administrators should consider increasing PE time in pursuit of higher academic test scores, and PE practitioners should emphasize cardiovascular fitness over BMI reduction.^

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Objective. The purpose of this study was to examine the association of perceived stress and passing the fitness test in a cohort of Department of Defense active duty members. Reports of this association have been suggested in numerous articles. Methods. The 2005 DoD Survey of Health Related Behaviors Among Active Duty Military Personnel was used to examine the association between the participants’ perceived levels of stress from family and/or work related sources and the respondents’ last required fitness test taking into account potential confounder of the association. Measures of association were obtained from logistic regression models. Results. Participants who experienced “some” or “a lot” of stress either from work sources (OR 0.69, 95% CI: 0.58-0.87) or from personal/family sources (OR 0.70, 95% CI: 0.57-0.86) were less likely to pass the fitness test when compared to their counterparts who experienced “none” or “a little” stress. Additionally, those who reported “some” or “a lot” of stress either from work sources (OR 0.54, 95% CI: 0.41-0.70) or from personal/family sources (OR 0.54, 95% CI: 0.44-0.67) that interfered with their military duties were also less likely to pass the fitness test. The multivariate adjustment only slightly reduced the unadjusted association. Conclusions . An association exists between perceived stress levels and outcome of fitness testing. The higher the level of stress perceived, the less likely the person will be to pass the fitness test. Stress-related intervention might be useful to help the military members to achieve the level of fitness needed to perform their duties.^

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Context. Alzheimer’s disease is a major source of morbidity and mortality in aging societies. Preventive measures, such as increasing cardiorespiratory fitness, to reduce the risk of Alzheimer’s disease mortality have not been sufficiently examined.^ Objective. To examine the association between levels of cardiorespiratory fitness and Alzheimer’s disease mortality.^ Design, Setting, and Patients. A prospective cohort study of 53,911 men and 18,876 women (mean age, 51.4 [SD, 10.0] years; range 20-88) enrolled in the Cooper Center Longitudinal Study who completed a baseline health examination during 1970-2006. The primary exposure, cardiorespiratory fitness, was assessed via a maximal exercise test. Fitness was categorized according to age- and sex-specific tertiles based on the participants’ distribution of maximal treadmill exercise test duration, in metabolic equivalent tasks (METs). The main outcome measure was Alzheimer’s disease mortality, defined as the underlying or contributing cause of death using the National Death Index and death certificates through December 31, 2006.^ Results. There were 175 Alzheimer’s disease deaths during a mean follow up of 37 years and 1,309,170 person-years of exposure. Women in the high fitness category had a 70% reduction in risk of Alzheimer’s mortality compared to women in the low fitness category (HR=0.3; 95% CI, 0.1-0.8; P=.02), while adjusting for potential confounders. Similarly, women in the moderate fitness category had a 70% reduction in risk for AD mortality compared to women in the low fit category (HR=0.3; 95% CI, 0.1-0.7; P=.005). Among men, the relationship between fitness level and AD mortality risk was examined but none were of statistical significance. The adjusted comparison of men in the high fitness category to low fit men yielded an HR of 0.9 (95% CI, 0.6-1.5; P=.79), while moderately fit men compared to low fit men yielded an HR of 1.3 (95% CI, 0.9-1.9; P=.21).^ Conclusions. Higher levels of cardiorespiratory fitness were associated with decreased risk of AD mortality, in women. No statistically significant association was found among men. Physical fitness may be an important protective factor against Alzheimer’s disease death in women, further supporting its clinical and public health values.^