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Sample records for factors limiting endurance

  1. Factors limiting endurance of armor, artillery, and infantry units under simulated NBC conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, T.M.; Tharion, W.J.; Banderet, L.E.; Lussier, A.R.

    1986-03-13

    The war of the future will require 72-hour operations in environments contaminated with nuclear/biological/chemical (NBC) agents. The 1985 P2NBC2 (Physiological and Psychological Effects of NBC and Extended Operations on Combined Arms Crews) Program assessed soldier endurance and performance under simulated NBC conditions. A total of 175 soldiers were observed during four tests differing in design, site, climatic conditions, and performance demands. In all but one of the iterations where the full chemical-protective ensemble (MOPP 4) was used without cooling, soldier endurance fell far short of the projected requirement. Psychological data were analyzed to determine which factors were associated with the incidence of casualties. The findings showed that perceived intensity of symptoms resembling the hyperventilation syndrome was significantly greater in soldiers classified as Casualties. Five of these symptoms (painful breathing, difficulty breathing, shortness of breath, headache, and nausea) showed Casualty-Survivor differences in all tests. Symptom intensity was attributed to two factors. (1) External conditions. Thermal stress exacerbated the five basic symptoms, induced others (tetany and paresthesia), and decreased endurance. Periodic relief from respirator use attenuated these symptoms and enhanced endurance. (2) Individual differences. Significant Casualty-Survivor differences in anxiety, depression, and cognitive strategy scores indicated that perception of hyperventilation symptoms and endurance were related to personality variables. Hyperventilation symptoms could incapacitate the soldier or induce removal of the protective mask under actual chemical attack.

  2. The limits of human endurance: what is the greatest endurance performance of all time? Which factors regulate performance at extreme altitude?

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    Noakes, Timothy David

    2007-01-01

    Humans evolved as an athletic species able to run in the midday heat, to throw with exquisite accuracy and to strike powerfully despite relatively weak upper arms compared to those of the great apes. The true extent to which humans could run long distances was first tested in a unique series of 6-day foot races contested between 1874 and 1888 by professional athletes from England and the United States. These athletes typically would have expended approximately 60,000 kcal (24.12 MJ) of energy during these races. The discovery of the bicycle soon caused the replacement of these races by 6-day cycling races which, in turn, led to the modern day Tour de France, the cycling race across America (RaAM) and two running races across the width of the United States in 1928 and 1929. The total energy expenditures during these different events can be estimated at approximately 168,000, 180,000 and 340,000 kcal respectively. But, in terms of the total energy expenditure, all these performances pale somewhat when compared to that of Robert Falcon Scott's Polar party during the 1911/12 British Antarctic Expedition. For most of 159 consecutive days, Scott's team man-hauled for 10 hours a day to the South Pole and back covering a distance of 2500 km. Their predicted total energy expenditure per individual would have been about 1 million kcal, making theirs, by some margin, the greatest sustained endurance athletic performance of all time. Interestingly, the dogs that provided the pulling power for Norwegian Roald Amundsen's team that was the first to reach the South Pole, 35 days before Scott's party, would have expended about 500,000 kcal in their 97 day trip, making theirs the greatest animal "sporting" performance on record. By contrast, mountain climbers expend only approximately 4000 kcal/day when climbing at extreme altitudes (above 4000 m). This relatively low rate of energy expenditure results from the low exercise intensities that can be sustained at extreme altitude. Here

  3. Master athletes are extending the limits of human endurance

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    Romuald Lepers

    2016-12-01

    Full Text Available The increased participation of master athletes (i.e. > 40 years old in endurance and ultra-endurance events (> 6h duration over the past few decades has been accompanied by an improvement in their performances at a much faster rate than their younger counterparts. Ageing does however result in a decrease in overall endurance performance. Such age-related declines in performance depend upon the modes of locomotion, event duration and gender of the participant. For example, smaller age-related declines in cycling performance than in running and swimming have been documented. The relative stability of gender differences observed across the ages suggests that the age-related declines in physiological function did not differ between males and females. Among the main physiological determinants of endurance performance, the maximal oxygen consumption (VO2max appears to be the parameter that is most altered by age. Exercise economy and the exercise intensity at which a high fraction of VO2max can be sustained (i.e. lactate threshold, seem to decline to a lesser extent with advancing age. The ability to maintain a high exercise-training stimulus with advancing age is emerging as the single most important means of limiting the rate of decline in endurance performance. By constantly extending the limits of (ultra-endurance, master athletes therefore represent an important insight into the ability of humans to maintain physical performance and physiological function with advancing age.

  4. Endurance Factors Improve Hippocampal Neurogenesis and Spatial Memory in Mice

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    Kobilo, Tali; Yuan, Chunyan; van Praag, Henriette

    2011-01-01

    Physical activity improves learning and hippocampal neurogenesis. It is unknown whether compounds that increase endurance in muscle also enhance cognition. We investigated the effects of endurance factors, peroxisome proliferator-activated receptor [delta] agonist GW501516 and AICAR, activator of AMP-activated protein kinase on memory and…

  5. Work criteria for stress conditions using heat-resistant materials having limited endurance

    Energy Technology Data Exchange (ETDEWEB)

    Kheyn, Ye.A.

    1980-01-01

    The effect of stress concentrations and material properties on endurance limits. The parameter properties are theoretically founded and define the comparative sensitivity of materials to stress concentration over prolonged statistical breakdowns.

  6. Limitations of Reliability for Long-Endurance Human Spaceflight

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    Owens, Andrew C.; de Weck, Olivier L.

    2016-01-01

    Long-endurance human spaceflight - such as missions to Mars or its moons - will present a never-before-seen maintenance logistics challenge. Crews will be in space for longer and be farther way from Earth than ever before. Resupply and abort options will be heavily constrained, and will have timescales much longer than current and past experience. Spare parts and/or redundant systems will have to be included to reduce risk. However, the high cost of transportation means that this risk reduction must be achieved while also minimizing mass. The concept of increasing system and component reliability is commonly discussed as a means to reduce risk and mass by reducing the probability that components will fail during a mission. While increased reliability can reduce maintenance logistics mass requirements, the rate of mass reduction decreases over time. In addition, reliability growth requires increased test time and cost. This paper assesses trends in test time requirements, cost, and maintenance logistics mass savings as a function of increase in Mean Time Between Failures (MTBF) for some or all of the components in a system. In general, reliability growth results in superlinear growth in test time requirements, exponential growth in cost, and sublinear benefits (in terms of logistics mass saved). These trends indicate that it is unlikely that reliability growth alone will be a cost-effective approach to maintenance logistics mass reduction and risk mitigation for long-endurance missions. This paper discusses these trends as well as other options to reduce logistics mass such as direct reduction of part mass, commonality, or In-Space Manufacturing (ISM). Overall, it is likely that some combination of all available options - including reliability growth - will be required to reduce mass and mitigate risk for future deep space missions.

  7. Limitations in intense exercise performance of athletes - effect of speed endurance training on ion handling and fatigue development

    DEFF Research Database (Denmark)

    Hostrup, Morten; Bangsbo, Jens

    2016-01-01

    Mechanisms underlying fatigue development and limitations for performance during intense exercise have been intensively studied during the past couple of decades. Fatigue development may involve several interacting factors and depends on type of exercise undertaken and training level...... and power output during intense exercise. Regular speed endurance training (SET), i.e. exercise performed at intensities above that corresponding to maximum oxygen consumption (VO2max ), enhances intense exercise performance. However, most of the studies that have provided mechanistic insight...

  8. Endurance sport practice as a risk factor for atrial fibrillation and atrial flutter.

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    Mont, Lluís; Elosua, Roberto; Brugada, Josep

    2009-01-01

    Although the benefits of regular exercise in controlling cardiovascular risk factors have been extensively proven, little is known about the long-term cardiovascular effects of regular and extreme endurance sport practice, such as jogging, cycling, rowing, swimming, etc. Recent data from a small series suggest a relationship between regular, long-term endurance sport practice and atrial fibrillation (AF) and flutter. Reported case control studies included less than 300 athletes, with mean age between 40 and 50. Most series recruited only male patients, or more than 70% males, who had been involved in intense training for many years. Endurance sport practice increases between 2 and 10 times the probability of suffering AF, after adjusting for other risk factors. The possible mechanisms explaining the association remain speculative. Atrial ectopic beats, inflammatory changes, and atrial size have been suggested. Some of the published studies found that atrial size was larger in athletes than in controls, and this was a predictor for AF. It has also been shown that the left atrium may be enlarged in as many as 20% of competitive athletes. Other proposed mechanisms are increased vagal tone and bradycardia, affecting the atrial refractory period; however, this may facilitate rather than cause the arrhythmia. In summary, recent data suggest an association between endurance sport practice and atrial fibrillation and flutter. The underlying mechanism explaining this association is unclear, although structural atrial changes (dilatation and fibrosis) are probably present. Larger longitudinal studies and mechanistic studies are needed to further characterize the association to clarify whether a threshold limit for the intensity and duration of physical activity may prevent AF, without limiting the cardiovascular benefits of exercise.

  9. Physiological and biomechanical factors associated with elite endurance cycling performance.

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    Coyle, E F; Feltner, M E; Kautz, S A; Hamilton, M T; Montain, S J; Baylor, A M; Abraham, L D; Petrek, G W

    1991-01-01

    In this study we evaluated the physiological and biomechanical responses of "elite-national class" (i.e., group 1; N = 9) and "good-state class" (i.e., group 2; N = 6) cyclists while they simulated a 40 km time-trial in the laboratory by cycling on an ergometer for 1 h at their highest power output. Actual road racing 40 km time-trial performance was highly correlated with average absolute power during the 1 h laboratory performance test (r = -0.88; P less than 0.001). In turn, 1 h power output was related to each cyclists' VO2 at the blood lactate threshold (r = 0.93; P less than 0.001). Group 1 was not different from group 2 regarding VO2max (approximately 70 ml.kg-1.min-1 and 5.01 l.min-1) or lean body weight. However, group 1 bicycled 40 km on the road 10% faster than group 2 (P less than 0.05; 54 vs 60 min). Additionally, group 1 was able to generate 11% more power during the 1 h performance test than group 2 (P less than 0.05), and they averaged 90 +/- 1% VO2max compared with 86 +/- 2% VO2max in group 2 (P = 0.06). The higher performance power output of group 1 was produced primarily by generating higher peak torques about the center of the crank by applying larger vertical forces to the crank arm during the cycling downstroke. Compared with group 2, group 1 also produced higher peak torques and vertical forces during the downstroke even when cycling at the same absolute work rate as group 2. Factors possibly contributing to the ability of group 1 to produce higher "downstroke power" are a greater percentage of Type I muscle fibers (P less than 0.05) and a 23% greater (P less than 0.05) muscle capillary density compared with group 2. We have also observed a strong relationship between years of endurance training and percent Type I muscle fibers (r = 0.75; P less than 0.001). It appears that "elite-national class" cyclists have the ability to generate higher "downstroke power", possibly as a result of muscular adaptations stimulated by more years of endurance

  10. Laser Cut Nitinol Tubing Fatigue Coupon: Design, Testing, and Endurance Limit

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    Forcucci, Stephen J.

    2014-07-01

    Nitinol medical device implants made from a laser cut tubing process (i.e., stents, valve structures, etc.) frequently require a fatigue durability assessment, which necessitates determining the material fatigue properties. Towards the goal of determining the strain-based endurance limit of medical grade superelastic Nitinol tubing, a coupon was designed and evaluated via FEA using Abaqus software, produced via laser cutting, shape setting, and electro-polishing processes, and then fatigue tested to 10 million cycles. FEA was used to determine the strain versus alternating displacement amplitude for the coupon. Error due to dimensional tolerances was determined. The coupons were then fatigue tested in a 37 °C temperature deionized water bath at alternating strain levels ranging from 0.75 to 4.0% at zero mean strain. Sample replication was greater than 90%, and the median alternating strain fatigue limit was determined via two methods. Confidence and reliability with maximum likelihood statistics are used to present a strain-based endurance limit for the material. The results seem to differ from previous published values.

  11. Eccentric endurance exercise economically improves metabolic and inflammatory risk factors.

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    Zeppetzauer, Markus; Drexel, Heinz; Vonbank, Alexander; Rein, Philipp; Aczel, Stefan; Saely, Christoph H

    2013-08-01

    Exercise is a cornerstone of cardiovascular prevention. Because many individuals are not willing or not able to perform regular exercise, new methods of exercise (like eccentric exercise) are necessary. Eccentric endurance exercise is supposed to be less strenuous than concentric exercise but its effects on glucose and lipid metabolism in relation to energy expenditure are unclear. We randomly allocated 45 healthy sedentary individuals to one of two groups, each hiking upwards or downwards for 2 months, with a crossover for a further 2 months; for the opposite way, a cable car was used. The difference in altitude was 540 metres; the distance was covered between three and five times a week. Energy expenditure was assessed for each hiking period. Both eccentric and concentric endurance exercise improved glucose tolerance vs. baseline (by 4.1%, p = 0.136; 6.2%, p = 0.023, respectively). Of note, adjustment for energy expenditure per exercise unit (127 ± 22 kcal/unit with eccentric and 442 ± 78 kcal/unit with concentric exercise) revealed a significantly greater improvement of glucose tolerance per kilocalorie spent by eccentric than by concentric exercise (4-times more economical; 0.1123 mg h/dl/kcal vs. 0.0245 mg h/dl/kcal; p = 0.038). Also the decrease of low-density lipoprotein (LDL) cholesterol per kilocalorie spent was significantly stronger with eccentric exercise (0.0982 mg/dl/kcal vs. 0.0346 mg/dl/kcal, p = 0.014). Serum levels of C-reactive protein and creatine kinase activity were reduced in both groups. Eccentric endurance exercise economically improves glucose tolerance and LDL cholesterol. It therefore is a promising new exercise modality for individuals who are not able to participate in more strenuous exercise regimens.

  12. Endurance Exercise Reduces Hepatic Fat Content and Serum Fibroblast Growth Factor 21 Levels in Elderly Men.

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    Taniguchi, Hirokazu; Tanisawa, Kumpei; Sun, Xiaomin; Kubo, Takafumi; Higuchi, Mitsuru

    2016-01-01

    Age-related hepatic fat accumulation increases the risk of cardiometabolic diseases, and the fibroblast growth factor (FGF) 21-resistant state caused by fatty liver underlies the pathogenesis of these diseases. Previous studies suggested that a higher level of cardiorespiratory fitness was associated with both lower hepatic fat content and serum FGF21 levels; however, the effect of endurance exercise on hepatic fat content and serum FGF21 concentration has not been studied. Therefore, we aimed to elucidate whether endurance exercise reduced hepatic fat content and serum FGF21 levels. This is a randomized crossover trial. The study setting was an institutional practice. Thirty-three elderly Japanese men participated in the study. The intervention was a 5-week endurance exercise program comprising three cycle ergometer sessions per week. Hepatic fat content was assessed by proton magnetic resonance spectroscopy, and serum FGF21 level was determined by ELISA. A 5-week endurance exercise program decreased the hepatic fat content and serum FGF21 levels without weight loss, and the changes were higher in the exercise period than in the control period (P = .021 and P = .026, respectively). Correlation analysis demonstrated that only the change in hepatic fat content was significantly and positively correlated with change in serum FGF21 levels (r = 0.366, P = .006). A 5-week endurance exercise program decreased hepatic fat content and serum FGF21 levels without weight loss in elderly men, and exercise-induced hepatic fat reduction mediated the reduction in serum FGF21 levels. These findings suggest that endurance exercise modulates hepatic fat content and FGF21 resistance, regardless of obesity status.

  13. Oxidative stress in endurance flight: an unconsidered factor in bird migration.

    Directory of Open Access Journals (Sweden)

    Susanne Jenni-Eiermann

    Full Text Available Migrating birds perform extraordinary endurance flights, up to 200 h non-stop, at a very high metabolic rate and while fasting. Such an intense and prolonged physical activity is normally associated with an increased production of reactive oxygen and nitrogen species (RONS and thus increased risk of oxidative stress. However, up to now it was unknown whether endurance flight evokes oxidative stress. We measured a marker of oxidative damage (protein carbonyls, PCs and a marker of enzymatic antioxidant capacity (glutathione peroxidase, GPx in the European robin (Erithacus rubecula, a nocturnal migrant, on its way to the non-breeding grounds. Both markers were significantly higher in European robins caught out of their nocturnal flight than in conspecifics caught during the day while resting. Independently of time of day, both markers showed higher concentrations in individuals with reduced flight muscles. Adults had higher GPx concentrations than first-year birds on their first migration. These results show for the first time that free-flying migrants experience oxidative stress during endurance flight and up-regulate one component of antioxidant capacity. We discuss that avoiding oxidative stress may be an overlooked factor shaping bird migration strategies, e.g. by disfavouring long non-stop flights and an extensive catabolism of the flight muscles.

  14. Landscape genetics and limiting factors

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    Samuel A. Cushman; Andrew J. Shirk; Erin L. Landguth

    2013-01-01

    Population connectivity is mediated by the movement of organisms or propagules through landscapes. However, little is known about how variation in the pattern of landscape mosaics affects the detectability of landscape genetic relationships. The goal of this paper is to explore the impacts of limiting factors on landscape genetic processes using simulation...

  15. Postdeployment driving stress and related occupational limitations among veterans of Operation Iraqi Freedom and Operation Enduring Freedom.

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    Hwang, Eric J; Peyton, Claudia G; Kim, David K; Nakama-Sato, Kristine K; Noble, Amy E

    2014-01-01

    Difficulty in driving after deployment has emerged as an impediment for servicemembers returning from Operation Iraqi Freedom and Operation Enduring Freedom (OIF-OEF). This study explored postdeployment driving stress and related occupational limitations using two self-report instruments: the Driver's Stress Profile and the Driving and Occupational Limitations questionnaire. Data gathered from 103 OIF-OEF returnees confirmed that driving and related occupational issues occur postdeployment. Significant low to moderate correlations were found between postdeployment driving stress and limitations in community mobility, leisure, and social participation. The returnees who drove off base more frequently during deployment showed significantly higher levels of postdeployment driving stress than the returnees who drove off base less frequently. Moreover, the returnees who demonstrated higher levels of driving stress and occupational limitations required more time to resume normal driving postdeployment. Findings raise awareness about the need to design effective driver rehabilitation and community reintegration programs for this population.

  16. Respiratory muscle endurance is limited by lower ventilatory efficiency in post-myocardial infarction patients

    Directory of Open Access Journals (Sweden)

    Laura M. T. Neves

    2014-03-01

    Full Text Available Background: Reduced respiratory muscle endurance (RME contributes to increased dyspnea upon exertion in patients with cardiovascular disease. Objective: The objective was to characterize ventilatory and metabolic responses during RME tests in post-myocardial infarction patients without respiratory muscle weakness. Method: Twenty-nine subjects were allocated into three groups: recent myocardial infarction group (RG, n=9, less-recent myocardial infarction group (LRG, n=10, and control group (CG, n=10. They underwent two RME tests (incremental and constant pressure with ventilatory and metabolic analyses. One-way ANOVA and repeated measures one-way ANOVA, both with Tukey post-hoc, were used between groups and within subjects, respectively. Results: Patients from the RG and LRG presented lower metabolic equivalent and ventilatory efficiency than the CG on the second (50± 06, 50± 5 vs. 42± 4 and third part (50± 11, 51± 10 vs. 43± 3 of the constant pressure RME test and lower metabolic equivalent during the incremental pressure RME test. Additionally, at the peak of the incremental RME test, RG patients had lower oxygen uptake than the CG. Conclusions : Post-myocardial infarction patients present lower ventilatory efficiency during respiratory muscle endurance tests, which appears to explain their inferior performance in these tests even in the presence of lower pressure overload and lower metabolic equivalent.

  17. Descriptive epidemiology and risk factors for eliminations from Fédération Equestre Internationale endurance rides due to lameness and metabolic reasons (2008-2011).

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    Nagy, A; Murray, J K; Dyson, S J

    2014-01-01

    There is limited information on international endurance rides and on risk factors for eliminations. To describe and compare the frequency of occurrence of elimination due to lameness and metabolic reasons from Fédération Equestre Internationale (FEI) endurance rides (≥100 km) during 2008-2011 in all countries and to assess risk factors for elimination due to lameness and metabolic reasons. Retrospective unmatched case-control study. Data collected from the FEI website included the following: the country where the ride was held; the year; the result for each horse-rider combination; the number of entries in each class; whether the class was restricted to young riders; and the winning speed. Descriptive data were summarised, and univariable and multivariable logistic regression analyses were performed to assess risk factors for eliminations due to lameness and metabolic reasons. Between 2008 and 2011, there were 30,741 horse starts at FEI endurance rides of 100-160 km distance in 47 countries. Of all started horses, 30% were eliminated for lameness. Eliminations for metabolic reasons were recorded for 8.7% of all started horses. There was a large range of winning speeds amongst countries (10.2-29.5 km/h). Multivariable analysis revealed that the risk of elimination due to lameness was significantly associated with the country where the ride was held, the year, the distance of the ride and the number of entries. Elimination for metabolic reasons was significantly associated with the country where the ride was held, the year and the number of entries. Differences existed among elimination rates at FEI endurance rides in different countries (2008-2011). Lameness was the most common reason for elimination globally. These results provide objective global data on endurance riding that can replace anecdotal information, which has been the base of opinions, decisions and regulations. The Summary is available in Chinese - see Supporting information. © 2013 EVJ Ltd.

  18. Limiting factors of starch hydrolysis.

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    Colonna, P; Leloup, V; Buléon, A

    1992-10-01

    Foods appear as complex structures, in which starch may be present in different forms. These, including the molecular characteristics and the crystalline organization, depend on processing conditions and compositions of ingredients. The main changes in starch macro- and microstructures are the increase of surface area to volume ratio in the solid phase, the modification of the crystallinity as affected by gelatinization and gelation, and the depolymerization of amylose and amylopectin. Starch modification may be estimated by different methodologies, which should be selected according to the level of structure considered. When amylose and amylopectin are in solution, rapid and total hydrolysis leads to the formation of a mixture of linear oligosaccharides and branched alpha-limit dextrins. However, starch usually occurs in foods as solid structures. Structural factors of starchy materials influence their enzymic hydrolysis. A better understanding of the enzymatic process enables the identification of the structural factors limiting hydrolysis: diffusion of enzyme molecules, porosity of solid substrates, adsorption of enzymes onto solid substrates, and the catalytic event. A mechanistic modelling should be possible in the future.

  19. 'The engine just started coughing!' - Limits of physical performance, aging and career continuity in elite endurance sports.

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    Ronkainen, Noora J; Ryba, Tatiana V; Nesti, Mark S

    2013-12-01

    This research examines male endurance athletes' experience of aging and/or reaching the perceived limits of physical performance. More specifically, the current study aimed to explore how existential meanings attached to these experiences are connected with athletes' decision-making concerning career continuity and retirement. Life story interviews were conducted with 10 Finnish runners and/or orienteers aged between 25 and 62 and the data was analyzed with an existential-narrative framework. Four major storylines related to aging were identified: The end of an era, putting things in perspective, the attitude has to change and winning was never the only motive. Our results suggest that endurance athletes possess diverse ways of bringing meaning to the experience of aging, both confirming and resisting the dominant cultural narrative of decline. While three athletes' stories confirmed the normativity of retirement when unable to improve their results anymore, other athletes demonstrated career continuity and positive aspects in the late career years, such as lack of competitive anxiety, finding perspective and increased enjoyment in running. We suggest that through awareness of alternative narratives, sport psychology consultants may be able to help their clients to explore new meanings in the potentially challenging and beneficial experiences of aging and athletic retirement. © 2013.

  20. Self-regulatory strength depletion and muscle-endurance performance: a test of the limited-strength model in older adults.

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    Bray, Steven R; Martin Ginis, Kathleen A; Woodgate, Jennifer

    2011-07-01

    Self-regulation consumes a form of strength or energy. The authors investigated aftereffects of self-regulation depletion on muscle-endurance performance in older adults. Participants (N = 61, mean age = 71) were randomized to a self-regulation-depletion or control group and completed 2 muscle-endurance performance tasks involving isometric handgrip squeezing that were separated by a cognitive-depletion task. The depletion group showed greater deterioration of muscle-endurance performance than controls, F(1, 59) = 7.31, p = .009. Results are comparable to those of younger adults in a similar study and support Baumeister et al.'s limited-strength model. Self-regulation may contribute to central-nervous-system fatigue; however, biological processes may allow aging muscle to offset depletion of self-regulatory resources affecting muscle-endurance performance.

  1. Metabolic factors limiting performance in marathon runners.

    Directory of Open Access Journals (Sweden)

    Benjamin I Rapoport

    Full Text Available Each year in the past three decades has seen hundreds of thousands of runners register to run a major marathon. Of those who attempt to race over the marathon distance of 26 miles and 385 yards (42.195 kilometers, more than two-fifths experience severe and performance-limiting depletion of physiologic carbohydrate reserves (a phenomenon known as 'hitting the wall', and thousands drop out before reaching the finish lines (approximately 1-2% of those who start. Analyses of endurance physiology have often either used coarse approximations to suggest that human glycogen reserves are insufficient to fuel a marathon (making 'hitting the wall' seem inevitable, or implied that maximal glycogen loading is required in order to complete a marathon without 'hitting the wall.' The present computational study demonstrates that the energetic constraints on endurance runners are more subtle, and depend on several physiologic variables including the muscle mass distribution, liver and muscle glycogen densities, and running speed (exercise intensity as a fraction of aerobic capacity of individual runners, in personalized but nevertheless quantifiable and predictable ways. The analytic approach presented here is used to estimate the distance at which runners will exhaust their glycogen stores as a function of running intensity. In so doing it also provides a basis for guidelines ensuring the safety and optimizing the performance of endurance runners, both by setting personally appropriate paces and by prescribing midrace fueling requirements for avoiding 'the wall.' The present analysis also sheds physiologically principled light on important standards in marathon running that until now have remained empirically defined: The qualifying times for the Boston Marathon.

  2. The influence of selected factors and sport results of endurance horses on their saliva cortisol concentration.

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    Janczarek, I; Bereznowski, A; Strzelec, K

    2013-01-01

    The aim of the study was to define the influence of the selected factors (gender, age, transportation time, riding distance and air temperature during the ride) on the cortisol secretion and finding a correlation between the hormone level and the horses' sport results (veterinary parameters and the ride route parameters). The research was performed on 38 Arabian pure breed horses taking part in the endurance rides. The cortisol level was measured with enzyme-immunological method in saliva samples, taken four times from each horse. In order to verify the differences between the mean results the repeated measures design was applied. The significance of the differences between the mean values was determined by the Tukey test. To evaluate the interrelations between the analysed attributes Pearson's correlation analysis was applied. The cortisol level at rest was not affected by any of the analysed factors. In case of other results, the most significant influence (P cortisol level was noted in mares, horses running the longest distances and at the highest temperatures. A significant increase in the cortisol level was noted when the ride distance was longer. There were no clear correlation between the adrenal cortex activity and the veterinary parameters at different riding speed. High cortisol concentration can negatively affect the heart rate (HR) by increasing it, but it can simultaneously stimulate the body to fight dehydration.

  3. Nutritional Supplements for Endurance Athletes

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    Rasmussen, Christopher J.

    Athletes engaged in heavy endurance training often seek additional nutritional strategies to help maximize performance. Specific nutritional supplements exist to combat certain factors that limit performance beginning with a sound everyday diet. Research has further demonstrated that safe, effective, legal supplements are in fact available for today's endurance athletes. Several of these supplements are marketed not only to aid performance but also to combat the immunosuppressive effects of intense endurance training. It is imperative for each athlete to research the legality of certain supplements for their specific sport or event. Once the legality has been established, it is often up to each individual athlete to decipher the ethics involved with ingesting nutritional supplements with the sole intent of improving performance.

  4. ‘The engine just started coughing!’ — Limits of physical performance, aging and career continuity in elite endurance sports

    DEFF Research Database (Denmark)

    Ronkainen, Noora; Ryba, Tatiana; Nesti, Mark

    2013-01-01

    This research examines male endurance athletes' experience of aging and/or reaching the perceived limits of physical performance. More specifically, the current study aimed to explore how existential meanings attached to these experiences are connected with athletes' decision-making concerning ca...

  5. Limited Effects of Endurance or Interval Training on Visceral Adipose Tissue and Systemic Inflammation in Sedentary Middle-Aged Men

    Science.gov (United States)

    Cooper, Joshua H. F.; Collins, Blake E. G.; Adams, David R.; Robergs, Robert A.

    2016-01-01

    Purpose. Limited data exists for the effects of sprint-interval training (SIT) and endurance training (ET) on total body composition, abdominal visceral adipose tissue, and plasma inflammation. Moreover, whether “active” or “passive” recovery in SIT provides a differential effect on these measures remains uncertain. Methods. Sedentary middle-aged men (n = 62; 49.5 ± 5.8 y; 29.7 ± 3.7 kg·m2) underwent abdominal computed tomography, dual-energy X-ray absorptiometry, venepuncture, and exercise testing before and after the interventions, which included the following: 12 wks 3 d·wk−1 ET (n = 15; 50–60 min cycling; 80% HRmax), SIT (4–10 × 30 s sprint efforts) with passive (P-SIT; n = 15) or active recovery (A-SIT; n = 15); or nonexercise control condition (CON; n = 14). Changes in cardiorespiratory fitness, whole-body and visceral fat mass, and plasma systemic inflammation were examined. Results. Compared to CON, significant increases in interpolated power output (P-SIT, P 90% exercise compliance, there was no change in whole-body or visceral fat mass or plasma inflammation (P > 0.05). Conclusion. In sedentary middle-aged men, SIT was a time-effective alternative to ET in facilitating conditioning responses yet was ineffective in altering body composition and plasma inflammation, and compared to passive recovery, evidenced diminished conditioning responses when employing active recovery. PMID:27777795

  6. Management of Endurance Risk Factors: A Guide for Deep Draft Vessels

    Science.gov (United States)

    2001-02-01

    of 1990 (OPA 90) or Standards of Training, Certification and Watchkeeping for Seafarers ( STCW ) regarding hours of work and rest. The fundamental...should use this information along with the guidelines xiv provided in OPA 90 and STCW to minimize risks associated with crew endurance, to ensure crew

  7. Limiting factors in caribou population ecology

    Directory of Open Access Journals (Sweden)

    David R. Klein

    1991-10-01

    Full Text Available Caribou and wild reindeer populations fluctuate over time. On this fact there is general agreement. Factors responsible for population limitation and subsequent declines have been examined within the framework of animal population theory. There is, however, little agreement when factors limiting specific populations are generalized to Rangifer populations over broad geographic regions. Comparative examinations of wild Rangifer populations worldwide discloses that factors that have regulated those populations are highly variable between populations, apparently as a reflection of the differences in environmental variables unique to each population. Examples exist of populations where major regulating factors have been climatic extremes, predation, hunting mortality, food limitation, insects, parasites, disease, interspecific competition, and human developmental impacts or combinations of these factors. This diversity of limiting factors affecting caribou and wild reindeer populations is a reflection of the ecologial complexity of the species, a concept that has often been ignored in past efforts to reach management decisions by extrapolation from the limited localized knowledge available on the species.

  8. Role of thermal factors on aerobic capacity improvements with endurance training.

    Science.gov (United States)

    Young, A J; Sawka, M N; Quigley, M D; Cadarette, B S; Neufer, P D; Dennis, R C; Valeri, C R

    1993-07-01

    This investigation studied the importance of the rise in body temperature during exercise for aerobic capacity adaptations produced by endurance training. The approach used was to compare training effects produced by subjects exercising in hot (35 degrees C) water vs. cold (20 degrees C) water. Hot water was used to potentiate, and cold water to blunt, the rise in body temperature during exercise. Eighteen young men trained by cycle-ergometer exercise at 60% of maximal oxygen uptake (VO2max) while immersed to the neck in either hot (HWT, n = 9) or cold (CWT, n = 9) water for 60 min, 5 days/wk, for 8 wk. Before and after training, VO2max, erythrocyte volume, plasma volume, and vastus lateralis citrate synthase activity were measured. Training increased (P < 0.01) VO2max by 13%, with no difference between HWT and CWT in the magnitude of the effect. Erythrocyte volume increased 4% (P < 0.01) with training, with no difference between HWT and CWT in the magnitude of the effect. Plasma volume remained unchanged by training in both the HWT and CWT groups. Last, vastus lateralis citrate synthase activity increased by 38% with training, but there was no difference between HWT and CWT in the training effect. Thus, exercise-induced body temperature elevations are not an important stimulus for the aerobic adaptations to moderate-intensity endurance training.

  9. Fatigue induced by physical and mental exertion increases perception of effort and impairs subsequent endurance performance

    Directory of Open Access Journals (Sweden)

    Benjamin Pageaux

    2016-11-01

    Full Text Available Endurance performance involves the prolonged maintenance of constant or self-regulated power/velocity or torque/force. While the impact of numerous determinants of endurance performance has been previously reviewed, the impact of fatigue on subsequent endurance performance still needs to be documented. This review aims to present the impact of fatigue induced by physical or mental exertion on subsequent endurance performance. For the purpose of this review, endurance performance refers to performance during whole-body or single-joint endurance exercise soliciting mainly the aerobic energy system. First, the impact of physical and mental exertion on force production capacity is presented, with specific emphasize on the fact that solely physical exertion and not mental exertion induces a decrease in force production capacity of the working muscles. Then, the negative impact of fatigue induced by physical exertion and mental exertion on subsequent endurance performance is highlighted based on experimental data. Perception of effort being identified as the variable altered by both prior physical exertion and mental exertion, future studies should investigate the underlying mechanisms increasing perception of effort overtime and in presence of fatigue during endurance exercise. Perception of effort should be considered not only as marker of exercise intensity, but also as a factor limiting endurance performance. Therefore, using a psychophysiological approach to explain the regulation of endurance performance would allow a better understanding of the interaction between physiological and psychological phenomena known to impact endurance performance.

  10. Evaluation of Factors Limiting Corneal Donation.

    Science.gov (United States)

    Röck, Daniel; Wude, Johanna; Yoeruek, Efdal; Bartz-Schmidt, Karl Ulrich; Röck, Tobias

    2016-11-15

    BACKGROUND This study aimed to investigate factors limiting corneal donation at the University Hospital Tübingen. MATERIAL AND METHODS We retrospectively studied all hospital deaths from January 2012 to December 2015, considering each deceased patient as a potential corneal donor. During this period an ophthalmic resident managed corneal donor procurement on a full-time basis. Various factors limiting corneal donation were examined. RESULTS Among the 3412 deaths, 2937 (86.1%) displayed nonfulfillment of corneal donation. Consent for corneal donation was obtained in 475 cases (13.9%). The mean annual corneal donation rate was 13.9 donors per 100 deaths (range: 11.2-17.8). The leading causes of nonfulfillment of corneal donations were refusal to donate (49.8%, 1698 cases) and medical contraindications (23.6%, 805 cases). After next-of-kin interview of 2173 potential donors (109 potential donors were excluded because of logistical problems), willingness to participate in corneal donation was present in 475 cases (21.9%), whereas in 1698 cases (78.1%) corneal donation was refused. CONCLUSIONS Our study showed refusal to donate is the most important factor limiting corneal donation. It seems that increasing the knowledge of people about corneal donation through public education and media are necessary to address the corneal shortage.

  11. Experimental Investigation and Discussion on the Mechanical Endurance Limit of Nafion Membrane Used in Proton Exchange Membrane Fuel Cell

    Directory of Open Access Journals (Sweden)

    Yang Xiao

    2014-10-01

    Full Text Available As a solution of high efficiency and clean energy, fuel cell technologies, especially proton exchange membrane fuel cell (PEMFC, have caught extensive attention. However, after decades of development, the performances of PEMFCs are far from achieving the target from the Department of Energy (DOE. Thus, further understanding of the degradation mechanism is needed to overcome this obstacle. Due to the importance of proton exchange membrane in a PEMFC, the degradation of the membrane, such as hygrothermal aging effect on its properties, are particularly necessary. In this work, a thick membrane (Nafion N117, which is always used as an ionic polymer for the PEMFCs, has been analyzed. Experimental investigation is performed for understanding the mechanical endurance of the bare membranes under different loading conditions. Tensile tests are conducted to compare the mechanical property evolution of two kinds of bare-membrane specimens including the dog-bone and the deeply double edge notched (DDEN types. Both dog-bone and DDEN specimens were subjected to a series of degradation tests with different cycling times and wide humidity ranges. The tensile tests are repeated for both kinds of specimens to assess the strain-stress relations. Furthermore, Fourier transform infrared spectroscopy (FT-IR, X-ray diffraction (XRD and Scanning electron microscope (SEM observation and water absorption measurement were conducted to speculate the cause of this variation. The initial cracks along with the increasing of bound water content were speculated as the primary cause.

  12. The Psychological Attributes of Ultramarathon Runners and Factors Which Limit Endurance

    Science.gov (United States)

    1987-04-30

    consisted of a 20 item test measuring trait anxiety (Spielberger, Gorsuch & Lushene, 1970). 5 Procedure All registered runners in the Massanutten...30 22. Spielberger CD, Gorsuch RL, Lushene RE: STAI manual. Palo Alto, 1970, Consulting Psychologists Press Inc. 23. Thompson WR, Nequin ND, Lesmes

  13. Effects of resistance training on muscle strength, endurance, and motor unit according to ciliary neurotrophic factor polymorphism in male college students.

    Science.gov (United States)

    Hong, Ae-Rim; Hong, Sang-Min; Shin, Yun-A

    2014-09-01

    Changes in muscle mass and strength across the adult age span are variable and related to the ciliary neurotrophic factor (CNTF) genotype. In particular, a single CNTF haplotype (1357 G→A) is important for neuronal and muscular developments and may be associated with muscle strength response to resistance training. We examined whether CNTF genotype differentially influences the effect of resistance training on neuromuscular improvement in male college students. Resistance training of the upper extremities comprised 3 sets at 75%-85% intensity per 1 repetition maximum, 3 times a week, for a total of 8 weeks. We measured isokinetic muscle function of the elbow joint with regard to strength (60°/s) and endurance (180°/s) by using an isokinetic dynamometer. The biceps brachii (BB) and brachioradialis muscles were studied using surface electromyography with spike-triggered averaging to assess surface-detected motor unit potential (SMUP) area. After resistance training, the SMUP of the BB increased significantly at 60°/s (p muscle strength and endurance may have resulted directly from resistance training rather than from genetic factors related to nerves in muscle tissue. Key PointsResistance training improves muscle strength and endurance in young men.This improvement in muscular strength and endurance is irrespective of CNTF genotypes.

  14. Effects of Endurance and Resistance Training on Plasma Levels of Chemerin and Factors Related to Obesity in Overweight and Obese Females

    Directory of Open Access Journals (Sweden)

    Mehri Jafari

    2015-07-01

    Full Text Available Background & aim: Obesity is accompanied with a lot of metabolic disorders such as changing Adipokines like Chemerin. The present study evaluated the effects of endurance and resistance training on Plasma levels of chemerin and Factors related to obesity in overweight and obese females. Methods: In this study 34 overweight and obese females with an average of age (22.29±2.49 years, body mass index (BMI (30.19±2.79 kg/m2, weight (77.23±10 kg participated voluntarily and were randomly assigned into two experimental groups (n=12 and one control group (n=10. Endurance and resistance training groups trained for 8 weeks (4 days a week, respectively with intensity of 65 to 80% maximum heart rate (HRmax and 65 to 80% one repetition maximum (1RM. In two steps of pre-test and post-test, after 12 hours of fasting, the blood samples were collected in the same conditions and ELIZA method was used to assess Plasma levels of Chemerin. Kolmogorov-Smirnove test was used to evaluate the normal distribution of data, the variation within groups using paired t-test and variation between groups analysis of variance (ANOVA and LSD were used in significant level (P<0.05. Results: Plasma Chemerin decreased significantly after 8 weeks of training in endurance group (P0.05. Also In the experimental groups, factors related to obesity (weight, fat mass, WHR and BMI were significantly decreased while the maximum oxygen consumption were significantly increased (P<0.05. Conclusions: Both endurance and resistance training, improved Factors related to Obesity and maximum oxygen consumption, but endurance training with a significant reduction in plasma chemerin, has a more effective role in health and reducing inflammation in overweight and obese females.

  15. Muscle force and endurance in untreated and human growth hormone or insulin-like growth factor-I-treated patients with growth hormone deficiency or Laron syndrome.

    Science.gov (United States)

    Brat, O; Ziv, I; Klinger, B; Avraham, M; Laron, Z

    1997-01-01

    Muscle force and endurance of four muscle groups (biceps, triceps, hamstrings and quadriceps) were measured by a computerized device in three groups: (A) 4 boys with isolated growth hormone deficiencies (IGHD) examined before at 10 and 24 months of hGH treatment; (B) 5 children (2 F, 3 M) with Laron syndrome were examined 3.5-4 years after initiation of insulin-like growth factor-I (IGF-I) treatment, and (C) comprised 8 untreated adults (5 F, 3 M) with Laron syndrome. For each patient, 2 matched controls, by age, sex, physical activity and height below the 50th percentile, were examined. GH- or IGF-I-deficient patients before treatment revealed reduced muscle force and endurance. GH treatment (0.6 U/kg/week) restored muscle force and endurance, progressively, mainly in the boys with puberty. Three to 4 years of IGF-I treatment (150 micrograms/kg/day) in patients with Laron syndrome proved to have a weaker effect than GH in restoring muscle force. The difference in effectiveness between hGH and IGF-I in restoring muscle force may be due to either the more marked muscle underdevelopment in Laron syndrome patients than in patients with IGHD or a difference in action potential between the two hormones.

  16. Talking yourself out of exhaustion : The effects of self-talk on endurance performance

    NARCIS (Netherlands)

    Blanchfield, A.W.; Hardy, J.; de Morree, H.M.; Staiano, W.; Marcora, S.M.

    2014-01-01

    Purpose: The psychobiological model of endurance performance proposes that the perception of effort is the ultimate determinant of endurance performance. Therefore, any physiological or psychological factor affecting the perception of effort will affect endurance performance. Accordingly, this novel

  17. Quantifying environmental limiting factors on tree cover using geospatial data.

    Directory of Open Access Journals (Sweden)

    Jonathan A Greenberg

    Full Text Available Environmental limiting factors (ELFs are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1 Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2 How are the ELFs distributed spatially? 3 To what extent are unmeasured environmental factors limiting tree cover? ELFs are difficult to quantify as they require significant sample sizes. We addressed this by using geospatial data over a relatively large spatial extent, where the wall-to-wall sampling ensures the inclusion of rare data points which define the minimum or maximum response to environmental factors. We tested mean temperature, minimum temperature, potential evapotranspiration (PET and PET minus precipitation (PET-P as potential limiting factors on percent tree cover. We found that the study area showed system-wide limitations on tree cover, and each of the factors showed evidence of being limiting on tree cover. However, only 1.2% of the total area appeared to be limited by the four (4 environmental factors, suggesting other unmeasured factors are limiting much of the tree cover in the study area. Where sites were near their theoretical maximum, non-forest sites (tree cover < 25% were primarily limited by cold mean temperatures, open-canopy forest sites (tree cover between 25% and 60% were primarily limited by evaporative demand, and closed-canopy forests were not limited by any particular environmental factor. The detection of ELFs is necessary in order to fully understand the width of limitations that species experience within their geographic range.

  18. 13 Factors Limiting Women's Involvement in Development: Lesson ...

    African Journals Online (AJOL)

    Nekky Umera

    the persistent and increasing burdens of poverty, malnutrition, poor health ... This paper investigates factors limiting an active involvement of rural women in .... and children, but decisions on economic and political issues are solely undertaken ...

  19. Critical Success Factors for Limited Service Hotels in Malaysia

    OpenAIRE

    Wong, Chee Keng

    2015-01-01

    Critical success factors were used originally in Information technology areas when it was first introduced but has since been applied generically in other industries. This study explores the critical success factors for limited service hotels in Malaysia from both customer and hotel operator/ business owners’ perspective. The literature presents information from tourism in general and in Malaysia, definition of limited service hotels and its relevance to the hospitality industry in Malaysia, ...

  20. LIMITING FACTORS FOR THE DEVELOPMENT OF THE SERBIAN HOSPITALITY INDUSTRY

    OpenAIRE

    Nikolina Kosar; Sasa Masic; Lidija Barjaktarovic; Mihaela Lazovic

    2016-01-01

    Heterogeneity and complexity determine multidisciplinary approach to the hospitality research. Identification and analysis of limited hospitality development factors imply very complex scientific approach. Case study methodology is applied on Republic of Serbia, which is transition country and candidate for EU accession. Research results identified key factors which had impact on lag, stagnation and contemporary level of hospitality development. Firstly, way of executed privatizat...

  1. Effects of an endurance cycling competition on resting serum insulin-like growth factor I (IGF-I) and its binding proteins IGFBP-1 and IGFBP-3

    Science.gov (United States)

    Chicharro, J; Lopez-Calderon, A; Hoyos, J; Martin-Velasco, A; Villa, G; Villanua, M; Lucia, A

    2001-01-01

    Objectives—To determine whether consecutive bouts of intense endurance exercise over a three week period alters serum concentrations of insulin-like growth factor I (IGF-I) and/or its binding proteins. Methods—Seventeen professional cyclists (mean (SEM) VO2MAX, 74.7 (2.1) ml/kg/min; age, 27 (1) years) competing in a three week tour race were selected as subjects. Blood samples were collected at each of the following time points: t0 (control, before the start of competition), t1 (end of first week), and t3 (end of third week). Serum levels of both total and free IGF-I and IGF binding proteins 1 and 3 (IGFBP-1 and IGFBP-3) were measured in each of the samples. Cortisol levels were measured in nine subjects. Results—A significant (p<0.01) increase was found in total IGF-I and IGFBP-1 at both t1 and t3 compared with to (IGF-I: 110.9 (17.7), 186.8 (12.0), 196.9 (14.7) ng/ml at t0, t1, and t3 respectively; IGFBP-1: 54.6 (6.6), 80.6 (8.0), and 89.2 (7.9) ng/ml at t0, t1, and t3 respectively). A significant (p<0.01) decrease was noted in free IGF-I at t3 compared with both to and t1 (t0: 0.9 (0.1) ng/ml; t1: 0.9 (0.1) ng/ml; t3: 0.7 (0.1) ng/ml); in contrast, IGFBP-3 levels remained stable throughout the race. Conclusions—It would appear that the increase in circulating levels of both IGF-I and its binding protein IGFBP-1 is a short term (one week) endocrine adaptation to endurance exercise. After three weeks of training, total IGF-I and IGFBP-1 remained stable, whereas free IGF-I fell below starting levels. Key Words: cycling; insulin-like growth factor; exercise; endurance; binding proteins PMID:11579061

  2. Effects of Resistance Training on Muscle Strength, Endurance, and Motor Unit According to Ciliary Neurotrophic Factor Polymorphism in Male College Students

    Directory of Open Access Journals (Sweden)

    Ae-Rim Hong, Sang-Min Hong, Yun-A Shin

    2014-09-01

    Full Text Available Changes in muscle mass and strength across the adult age span are variable and related to the ciliary neurotrophic factor (CNTF genotype. In particular, a single CNTF haplotype (1357 G→A is important for neuronal and muscular developments and may be associated with muscle strength response to resistance training. We examined whether CNTF genotype differentially influences the effect of resistance training on neuromuscular improvement in male college students. Resistance training of the upper extremities comprised 3 sets at 75%–85% intensity per 1 repetition maximum, 3 times a week, for a total of 8 weeks. We measured isokinetic muscle function of the elbow joint with regard to strength (60°/s and endurance (180°/s by using an isokinetic dynamometer. The biceps brachii (BB and brachioradialis muscles were studied using surface electromyography with spike-triggered averaging to assess surface-detected motor unit potential (SMUP area. After resistance training, the SMUP of the BB increased significantly at 60°/s (p < 0.05, but no difference in the CNTF genotype was observed. The SMUP of the BB at 180°/s increased significantly in the GG/AA genotype group compared with that in the GA genotype group (p < 0.05. The average power of the elbow flexor at 180°/s increased significantly after resistance training (p < 0.05, but again, no difference in the CNTF genotype was observed. Thus, improvements in muscle strength and endurance may have resulted directly from resistance training rather than from genetic factors related to nerves in muscle tissue.

  3. Dynamics of competitive systems with a single common limiting factor.

    Science.gov (United States)

    Kon, Ryusuke

    2015-02-01

    The concept of limiting factors (or regulating factors) succeeded in formulating the well-known principle of competitive exclusion. This paper shows that the concept of limiting factors is helpful not only to formulate the competitive exclusion principle, but also to obtain other ecological insights. To this end, by focusing on a specific community structure, we study the dynamics of Kolmogorov equations and show that it is possible to derive an ecologically insightful result only from the information about interactions between species and limiting factors. Furthermore, we find that the derived result is a generalization of the preceding work by Shigesada, Kawasaki, and Teramoto (1984), who examined a certain Lotka-Volterra equation in a different context.

  4. [Endurance sports and arythmias].

    Science.gov (United States)

    Burgan, H; Burri, H

    2013-03-01

    Endurance sports can predispose to the occurrence of certain arrhythmias, making them more frequent in athletes than in the general population. Endurance athletes often exhibit electrocardiographic modifications that are difficult to interpret without specific knowledge of the athlete's ECG. Some of these ECG modifications and arrhythmias are benign, however others can be potentially life threatening.

  5. Corn Response to Competition: Growth Alteration vs. Yield Limiting Factors

    Science.gov (United States)

    Understanding competition mechanisms among adjacent plants can improve site-specific management recommendations. This 2-yr study compared two hypotheses, yield limiting factors vs. behavior modification, to explain plant interactions. Corn was grown under different levels of stress by varying light ...

  6. Quantifying Environmental Limiting Factors on Tree Cover Using Geospatial Data

    NARCIS (Netherlands)

    Greenberg, Jonathan; Ferreira Dos Santos, Maria Joao; Dobrowski, Solomon; Vanderbilt, Vern; Ustin, Susan

    2015-01-01

    Environmental limiting factors (ELFs) are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1) Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2) Ho

  7. Factors limiting heterotrophic bacterial production in the southern Pacific Ocean

    Directory of Open Access Journals (Sweden)

    F. Van Wambeke

    2007-10-01

    Full Text Available The role of potential factors limiting bacterial growth was investigated along vertical and longitudinal gradients across the South Eastern Pacific Gyre. The effects of glucose, nitrate, ammonium and phosphate additions on heterotrophic bacterial production (using leucine technique were studied in parallel in unfiltered seawater samples incubated under natural daily irradiance. Longitudinally, the enrichments realized on the subsurface showed three types of responses. From the Marquesas plateau (8° W to approx 125° W, bacteria were not bottom-up controlled, as confirmed by the huge potential of growth in non-enriched seawater (43±24 times in 24 h. Within the Gyre (125° W–95° W, nitrogen alone stimulated leucine incorporation rates by a factor of 5.6±3.6, but rapidly labile carbon (glucose became a second limiting factor (enhancement factor 49±32 when the two elements were added. Finally from the border of the gyre to the Chilean upwelling (95° W–73° W, labile carbon was the only factor stimulating heterotrophic bacterial production. Interaction between phytoplankton and heterotrophic bacterial communities and the direct versus indirect effect of iron and macronutrients on bacterial production were also investigated in four selected sites: two sites on the vicinity of the Marquesas plateau, the centre of the gyre and the Eastern border of the gyre. Both phytoplankton and heterotrophic bacteria were limited by availability of nitrogen within the gyre, but not by iron. While iron limited phytoplankton at Marquesas plateau and at the eastern border of the gyre, heterotrophic bacteria were only limited by availability of labile DOC in those environments.

  8. Dehydration and endurance performance in competitive athletes.

    Science.gov (United States)

    Goulet, Eric D B

    2012-11-01

    The field of research examining the link between dehydration and endurance performance is at the dawn of a new era. This article reviews the latest findings describing the relationship between exercise-induced dehydration and endurance performance and provides the knowledge necessary for competitive, endurance-trained athletes to develop a winning hydration strategy. Acute, pre-exercise body weight loss at or above 3% may decrease subsequent endurance performance. Therefore, endurance athletes should strive to start exercise well hydrated, which can be achieved by keeping thirst sensation low and urine color pale and drinking approximately 5-10 mL/kg body weight of water 2 h before exercise. During exercise lasting 1 h or less, dehydration does not decrease endurance performance, but athletes are encouraged to mouth-rinse with sports drinks. During exercise lasting longer than 1 h, in which fluid is readily available, drinking according to the dictates of thirst maximizes endurance performance. In athletes whose thirst sensation is untrustworthy or when external factors such as psychological stress or repeated food intake may blunt thirst sensation, it is recommended to program fluid intake to maintain exercise-induced body weight loss around 2% to 3%.

  9. Massive three-loop form factor in the planar limit

    CERN Document Server

    Henn, Johannes; Smirnov, Vladimir A; Steinhauser, Matthias

    2016-01-01

    We compute the three-loop QCD corrections to the massive quark-anti-quark-photon form factors $F_1$ and $F_2$ in the large-$N_c$ limit. The analytic results are expressed in terms of Goncharov polylogarithms. This allows for a straightforward numerical evaluation. We also derive series expansions, including power suppressed terms, for three kinematic regions corresponding to small and large invariant masses of the photon momentum, and small velocities of the heavy quarks.

  10. Limiting factors for reforestation of mine spoils from Galicia (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Vega, F.A.; Covelo, E.F.; Andrade, M.L. [University of Vigo, Vigo (Spain)

    2005-02-01

    Mined areas are a continuing source of heavy metals and acidity that move off site in response to erosion. Revegetation of the mine tailings could limit the spread of these heavy metals and acidity. This study was conducted to evaluate, at four tailings on opencast mines of Galicia (Touro: copper mine; and Meirama: lignite mine, NW Spain), the chemical and physical soil quality indicators and limiting edaphic factors concerning forest production. Selected zones were: (1) The tailings formed by the waste materials from the depleted Touro mine; (2) the decantation site of deposited sludge coming from the copper extraction in the flotation stage; (3) and (4) tailings of 3 and 10 years old of the Meirama lignite mine. The main physical limitations of the mine soils are the low effective depth ({lt} 50cm), high stoniness ({gt} 30 percent) and high porosity ({gt} 60 percent); which make them vulnerable to soil erosion and seriously interferes with the forest production. Soils coming from the decantation site of copper mine do not have physical limitations. The main chemical limitations of mine soils are their acidity (pH from 3.62 to 5.71), and aluminium saturation ({gt} 60 per cent in copper mine soils, and {gt} 20 per cent in lignite mine soils), low CECe (from 5.34 to 9.47 cmol{sub +}) kg{sup -1}), organic carbon (from 0.47 to 7.52 mg kg{sup -1}) and Ca{sup 2+} and Mg{sup 2+} contents, and imbalance between exchange bases. Lime and organic amendments are the most important factors in providing a suitable medium for plant growth.

  11. Glial cell line-derived neurotrophic factor (GDNF) expression and NMJ plasticity in skeletal muscle following endurance exercise.

    Science.gov (United States)

    Gyorkos, A M; McCullough, M J; Spitsbergen, J M

    2014-01-17

    Glial cell line-derived neurotrophic factor (GDNF) supports and maintains the neuromuscular system during development and through adulthood by promoting neuroplasticity. The aim of this study was to determine if different modes of exercise can promote changes in GDNF expression and neuromuscular junction (NMJ) morphology in slow- and fast-twitch muscles. Rats were randomly assigned to a run training (run group), swim training (swim group), or sedentary control group. GDNF protein content was determined by enzyme-linked immunosorbant assay. GDNF protein content increased significantly in soleus (SOL) following both training protocols (PGDNF content and total end plate area were positively correlated. End plate area decreased in EDL of the run group and increased in SOL of the swim group. The results indicate that GDNF expression and NMJ morphological changes are activity dependent and that different changes may be observed by varying the exercise intensity in slow- and fast-twitch fibers.

  12. LIMITING FACTORS FOR THE DEVELOPMENT OF THE SERBIAN HOSPITALITY INDUSTRY

    Directory of Open Access Journals (Sweden)

    Nikolina Kosar

    2016-12-01

    Full Text Available Heterogeneity and complexity determine multidisciplinary approach to the hospitality research. Identification and analysis of limited hospitality development factors imply very complex scientific approach. Case study methodology is applied on Republic of Serbia, which is transition country and candidate for EU accession. Research results identified key factors which had impact on lag, stagnation and contemporary level of hospitality development. Firstly, way of executed privatization process of hospitality companies in Serbia i.e. only ownership transformation, as part of business transformation, was done (organizational, management, technological, financial and human resources parts of business transformation didn’t implement. Secondly, non-acceptable terms and conditions of credit lines for financing privatization and future business of privatized hospitality companies. Furthermore, buyers of privatized hospitality companies didn’t prepared adequate projections of cash flow and sources of financing (owned and borrowed. Finally, technological development and human resources were result of the first mentioned limited factor. In order to improve business in hospitality industry in transition economies, all stakeholders should be involved. State should improve business environment. Educational institutions should create applicable programs on market. Investors should be ready to invest in technological and human resource development. Banks should implement the best financing practice from headquarters in EU.

  13. Radiation Pressure Acceleration: the factors limiting maximum attainable ion energy

    CERN Document Server

    Bulanov, S S; Schroeder, C B; Bulanov, S V; Esirkepov, T Zh; Kando, M; Pegoraro, F; Leemans, W P

    2016-01-01

    Radiation pressure acceleration (RPA) is a highly efficient mechanism of laser-driven ion acceleration, with with near complete transfer of the laser energy to the ions in the relativistic regime. However, there is a fundamental limit on the maximum attainable ion energy, which is determined by the group velocity of the laser. The tightly focused laser pulses have group velocities smaller than the vacuum light speed, and, since they offer the high intensity needed for the RPA regime, it is plausible that group velocity effects would manifest themselves in the experiments involving tightly focused pulses and thin foils. However, in this case, finite spot size effects are important, and another limiting factor, the transverse expansion of the target, may dominate over the group velocity effect. As the laser pulse diffracts after passing the focus, the target expands accordingly due to the transverse intensity profile of the laser. Due to this expansion, the areal density of the target decreases, making it trans...

  14. The combined impact of metabolic gene polymorphisms on elite endurance athlete status and related phenotypes.

    Science.gov (United States)

    Ahmetov, Ildus I; Williams, Alun G; Popov, Daniil V; Lyubaeva, Ekaterina V; Hakimullina, Albina M; Fedotovskaya, Olga N; Mozhayskaya, Irina A; Vinogradova, Olga L; Astratenkova, Irina V; Montgomery, Hugh E; Rogozkin, Viktor A

    2009-12-01

    Endurance performance is a complex phenotype subject to the influence of both environmental and genetic factors. Although the last decade has seen a variety of specific genetic factors proposed, many in metabolic pathways, each is likely to make a limited contribution to an 'elite' phenotype: it seems more likely that such status depends on the simultaneous presence of multiple such variants. The aim of the study was to investigate individually and in combination the association of common metabolic gene polymorphisms with endurance athlete status, the proportion of slow-twitch muscle fibers and maximal oxygen consumption. A total of 1,423 Russian athletes and 1,132 controls were genotyped for 15 gene polymorphisms, of which most were previously reported to be associated with athlete status or related intermediate phenotypes. Muscle fiber composition of m. vastus lateralis in 45 healthy men was determined by immunohistochemistry. Maximal oxygen consumption of 50 male rowers of national competitive standard was determined during an incremental test to exhaustion on a rowing ergometer. Ten 'endurance alleles' (NFATC4 Gly160, PPARA rs4253778 G, PPARD rs2016520 C, PPARGC1A Gly482, PPARGC1B 203Pro, PPP3R1 promoter 5I, TFAM 12Thr, UCP2 55Val, UCP3 rs1800849 T and VEGFA rs2010963 C) were first identified showing discrete associations with elite endurance athlete status. Next, to assess the combined impact of all 10 gene polymorphisms, all athletes were classified according to the number of 'endurance' alleles they possessed. The proportion of subjects with a high (≥9) number of 'endurance' alleles was greater in the best endurance athletes compared with controls (85.7 vs. 37.8%, P = 7.6 × 10(-6)). The number of 'endurance' alleles was shown to be positively correlated (r = 0.50; P = 4.0 × 10(-4)) with the proportion of fatigue-resistant slow-twitch fibers, and with maximal oxygen consumption (r = 0.46; P = 7.0 × 10(-4)). These data suggest that the likelihood of

  15. Success factors and limitations of efficient internal communication

    Directory of Open Access Journals (Sweden)

    Dariusz Tworzydło

    2015-03-01

    Full Text Available The article covers the key issues of internal communication within an organization. It highlights the benefits of implementation of transparent communication principles for a company. It identifies objectives and presents selected communication tools. In the article, also guidelines for carrying out research in the context of development of an internal communication strategy can be found. Selected research areas of the process of planning and implementation of strategic assumptions have been presented. Factors limiting effective implementation of an internal communication strategy have been discussed.

  16. Enduring, Handling-Evoked Enhancement of Hippocampal Memory Function and Glucocorticoid Receptor Expression Involves Activation of the Corticotropin-Releasing Factor Type 1 Receptor

    Science.gov (United States)

    Fenoglio, Kristina A.; Brunson, Kristen L.; Avishai-Eliner, Sarit; Stone, Blake A.; Kapadia, Bhumika J.; Baram, Tallie Z.

    2011-01-01

    Early-life experience, including maternal care, influences hippocampus-dependent learning and memory throughout life. Handling of pups during postnatal d 2–9 (P2–9) stimulates maternal care and leads to improved memory function and stress-coping. The underlying molecular mechanisms may involve early (by P9) and enduring reduction of hypothalamic corticotropin-releasing factor (CRF) expression and subsequent (by P45) increase in hippocampal glucocorticoid receptor (GR) expression. However, whether hypothalamic CRF levels influence changes in hippocampal GR expression (and memory function), via reduced CRF receptor activation and consequent lower plasma glucocorticoid levels, is unclear. In this study we administered selective antagonist for the type 1 CRF receptor, NBI 30775, to nonhandled rats post hoc from P10–17 and examined hippocampus-dependent learning and memory later (on P50–70), using two independent paradigms, compared with naive and vehicle-treated nonhandled, and naive and antagonist-treated handled rats. Hippocampal GR and hypothalamic CRF mRNA levels and stress-induced plasma corticosterone levels were also examined. Transient, partial selective blockade of CRF1 in nonhandled rats improved memory functions on both the Morris watermaze and object recognition tests to levels significantly better than in naive and vehicle-treated controls and were indistinguishable from those in handled (naive, vehicle-treated, and antagonist-treated) rats. GR mRNA expression was increased in hippocampal CA1 and the dentate gyrus of CRF1-antagonist treated nonhandled rats to levels commensurate with those in handled cohorts. Thus, the extent of CRF1 activation, probably involving changes in hypothalamic CRF levels and release, contributes to the changes in hippocampal GR expression and learning and memory functions. PMID:15932935

  17. Altitude and endurance training.

    Science.gov (United States)

    Rusko, Heikki K; Tikkanen, Heikki O; Peltonen, Juha E

    2004-10-01

    The benefits of living and training at altitude (HiHi) for an improved altitude performance of athletes are clear, but controlled studies for an improved sea-level performance are controversial. The reasons for not having a positive effect of HiHi include: (1) the acclimatization effect may have been insufficient for elite athletes to stimulate an increase in red cell mass/haemoglobin mass because of too low an altitude (stress with possible overtraining symptoms and an increased frequency of infections. Moreover, the effects of hypoxia in the brain may influence both training intensity and physiological responses during training at altitude. Thus, interrupting hypoxic exposure by training in normoxia may be a key factor in avoiding or minimizing the noxious effects that are known to occur in chronic hypoxia. When comparing HiHi and HiLo (living high and training low), it is obvious that both can induce a positive acclimatization effect and increase the oxygen transport capacity of blood, at least in 'responders', if certain prerequisites are met. The minimum dose to attain a haematological acclimatization effect is > 12 h a day for at least 3 weeks at an altitude or simulated altitude of 2100-2500 m. Exposure to hypoxia appears to have some positive transfer effects on subsequent training in normoxia during and after HiLo. The increased oxygen transport capacity of blood allows training at higher intensity during and after HiLo in subsequent normoxia, thereby increasing the potential to improve some neuromuscular and cardiovascular determinants of endurance performance. The effects of hypoxic training and intermittent short-term severe hypoxia at rest are not yet clear and they require further study.

  18. ANTHROPOLOGY DIMENSIONS AS INDEPENDENT AEROBIC ENDURANCE

    Directory of Open Access Journals (Sweden)

    Ratko Pavlović

    2009-11-01

    Full Text Available Endurance as human capability is treated in two ways. Some authors define it as mobility capability, while others deny this theory. The denying of this theory lies in attitude that endurance is saturated with psychological factors (motivation and cardio- vascular factors as well and is often identified with aero power, typical dimension of fun- ctional diagnostics. Having that in mind this research enabled the obtaining of necessary informations which could contribute to the clearing up of these uncoordinated opinions. The research included 110 student of the III year Phisical Education in East Sarajevo, male gender. Nine (9 predictors has been applied (4 variables for mobility space estima- te, 5 variables for morphology and functional space estimate and variable used for the estimate of endurance race 1500m. Obtained results confirmed statistical significance of two functional capability variable of Harvard step test, Margarija test and mobility variable race 4x15 meters with the race results.

  19. Measured by the oxygen uptake in the field, the work of refuse collectors is particularly hard work: Are the limit values for physical endurance workload too low?

    Science.gov (United States)

    Preisser, Alexandra M; Zhou, Linfei; Velasco Garrido, Marcial; Harth, Volker

    2016-02-01

    Collecting waste is regarded as a benchmark for "particularly heavy" work. This study aims to determine and compare the workload of refuse workers in the field. We examined heart rate (HR) and oxygen uptake as parameters of workload during their daily work. Sixty-five refuse collectors from three task-specific groups (residual and organic waste collection, and street sweeping) of the municipal sanitation department in Hamburg, Germany, were included. Performance was determined by cardiopulmonary exercise testing (CPX) under laboratory conditions. Additionally, the oxygen uptake (VO2) and HR under field conditions (1-h morning shift) were recorded with a portable spiroergometry system and a pulse belt. There was a substantial correlation of both absolute HR and VO2 during CPX [HR/VO2 R 0.89 (SD 0.07)] as well as during field measurement [R 0.78 (0.19)]. Compared to reference limits for heavy work, 44% of the total sample had shift values above 30% heart rate reserve (HRR); 34% of the individuals had mean HR during work (HRsh) values that were above the HR corresponding to 30% of individual maximum oxygen uptake (VO2,max). All individuals had a mean oxygen uptake (VO2,1h) above 30% of VO2,max. HR as well as the measurement of VO2 can be valuable tools for investigating physiological workload, not only under laboratory conditions but also under normal working conditions in the field. Both in terms of absolute and relative HR and oxygen consumption, employment as a refuse collector should be classified in the upper range of defined heavy work. The limit of heavy work at about 33% of the individual maximum load at continuous work should be reviewed.

  20. An Important Factor in Improvement of the 400 m Run-speed Endurance%提高400 m跑成绩的重要因素--速度耐力

    Institute of Scientific and Technical Information of China (English)

    徐福生

    2014-01-01

    提高短跑运动员的成绩,从训练的指导思想而言,一是速度能力,二是发展速度耐力.400 m作为短跑项目,除了积极发辉他们的速度之外,还须重视速度耐力的训练.依据运动生理学研究成果及实践经验,阐述决定400 m成绩的重要因素---速度耐力.%Raising the grade of the sprinters,from the guiding ideology of training,one is speed abili-ty,the other is the development speed endurance.400m as a sprinter project,in addition to actively send their speed,must also attaches great importance to the speed endurance training.On the basis of exercise physiology research results and practical experience,the paper expounds important factor of 400 m -speed endurance.

  1. Is iron a limiting factor of Nodularia spumigena blooms?

    Directory of Open Access Journals (Sweden)

    Lidia Paczuska

    2003-12-01

    Full Text Available It is well known that a deficiency of iron, a trace element essential to every living organism, limits the growth of algae and cyanobacteria. Nodularia spumigena Mertens is a blue-green algae species inhabiting the Baltic region that often forms toxic blooms.     The aim of the study was to assess the growth of the toxic cyanobacteria with respect to iron bioavailability. The measured growth parameters were the numbers of cells (optical density, chlorophyll a and pheopigment a concentrations. The iron concentrations used ranged from 10-7 to 10-4 mol dm-3. Under iron stress conditions (<5 × 10-7 mol dm-3, growth inhibition, gradual pigment decay and cell mortality were observed. However, enriching the medium with complexing factors like citric acid and EDTA significantly stimulated the growth rate and chlorophyll a production. The citric acid - EDTA - Fe (5 × 10-7 mol dm-3 complex was demonstrably effective in stimulating the rate of cell division. Starting with 10-6 mol dm-3, the higher the iron(III concentration used in the media, the more intensive the growth of the cyanobacteria populations. This was most rapid in the presence of high iron concentrations (10-4 mol dm-3, regardless of the presence of complexing agents.     It appears that the growth of toxic cyanobacteria N. spumigena, and thus also its ability to form blooms, may well depend on iron availability in the environment.

  2. Endurance bounds of aerial systems

    Science.gov (United States)

    Harrington, Aaron M.; Kroninger, Christopher M.

    2014-06-01

    Within the past few years micro aerial vehicles (MAVs) have received much more attention and are starting to proliferate into military as well as civilian roles. However, one of the major drawbacks for this technology currently, has been their poor endurance, usually below 10 minutes. This is a direct result of the inefficiencies inherent in their design. Often times, designers do not consider the various components in the vehicle design and match their performance to the desired mission for the vehicle. These vehicles lack a prescribed set of design guidelines or empirically derived design equations which often limits their design to selection of commercial off-the-shelf components without proper consideration of their affect on vehicle performance. In the current study, the design space for different vehicle configurations has been examined including insect flapping, avian flapping, rotary wing, and fixed wing, and their performance bounds are established. The propulsion system typical of a rotary wing vehicle is analyzed to establish current baselines for efficiency of vehicles at this scale. The power draw from communications is analyzed to determine its impact on vehicle performance. Finally, a representative fixed wing MAV is examined and the effects of adaptive structures as a means for increasing vehicle endurance and range are examined. This paper seeks to establish the performance bounds for micro air vehicles and establish a path forward for future designs so that efficiency may be maximized.

  3. Myasthenia gravis and endurance exercise.

    Science.gov (United States)

    Scheer, Bernd Volker; Valero-Burgos, Encarna; Costa, Ricardo

    2012-08-01

    This is the first report of a runner with myasthenia gravis who completed an ultra endurance event. Myasthenia gravis, a neuromuscular disease that usually results in skeletal muscle weakness, which worsens with exercise and strenuous aerobic exercise, is generally contraindicated. Our runner completed a 220-km, 5-day ultramarathon and presented with various symptoms including muscular skeletal weakness, cramps, generalized fatigue, unintelligible speech, involuntary eye and mouth movements, problems swallowing, food lodging in his throat, and problems breathing. Risk factors identified for exacerbations are running in extreme temperatures, prolonged runs (especially a distance of 30 km or more), running uphill, lack of sleep, and stress. The medical team was in the novel situation to look after a runner with myasthenia gravis and needed to be aware of the patient's condition, symptoms, and risk factors to safely care for him.

  4. Rapid method of determining factors limiting bacterial growth in soil

    OpenAIRE

    Aldén Demoling, Louise; Demoling, Fredrik; Bååth, Erland

    2001-01-01

    A technique to determine which nutrients limit bacterial growth in soil was developed. The method was based on measuring the thymidine incorporation rate of bacteria after the addition of C, N, and P in different combinations to soil samples. First, the thymidine incorporation method was tested in two different soils: an agricultural soil and a forest humus soil. Carbon (as glucose) was found to be the limiting substance for bacterial growth in both of these soils. The effect of adding differ...

  5. Limiter

    Science.gov (United States)

    Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.

    1984-10-19

    A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.

  6. Limiting factors of exercise performance 1 year after lung transplantation

    NARCIS (Netherlands)

    Reinsma, G. D.; ten Hacken, N. H. T.; Grevink, R. G.; van der Bij, W.; Koer, G. H.; van Weert, E.

    2006-01-01

    Background: After lung transplantation (LTx). exercise capacity frequently remains limited, despite significantly improved pulmonary function. The aim of this study was to evaluate maximal exercise capacity and peripheral muscle force before and 1 year after LTx, and to determine whether peripheral

  7. [Endurance training and cardial adaptation (athlete's heart)].

    Science.gov (United States)

    Dickhuth, Hans-Hermann; Röcker, Kai; Mayer, Frank; König, Daniel; Korsten-Reck, Ulrike

    2004-06-01

    One essential function of the cardiovascular system is to provide an adequate blood supply to all organs, including the skeletal muscles at rest and during exercise. Adaptation to chronic exercise proceeds mainly via the autonomic nervous system. On the one hand, peripheral muscles influence the autonomic reactions through "feedback" control via ergoreceptors, in particular, mechano- and chemoreceptors. On the other hand, there is central control in the sense of a "feed forward" regulation, e. g., the reaction of an athlete before competition. Along with other influential factors, such as circulatory presso-, chemo-, and volume receptors, the incoming impulses are processed in vegetative centers.A cardiovascular reaction, then, is the result of nerval and humoral sympathetic and parasympathetic activity. At rest, the parasympathetic tone dominates. It reduces heart frequency and conduction velocity. The high vagal tone is initially reduced with increasing physical exertion and switches at higher intensity to increasingly sympathetic activation. This mechanism of reaction to exercise is supported by inverse central and peripheral transmissions.Chronic endurance training leads to an improved local aerobic capacity of the exercised musculature. At rest, it augments parasympathetic activity when the muscle mass is sufficiently large, i. e., 20-30% of the skeletal musculature. The extent of the adaptation depends on individual factors, such as scope, intensity of training, and type of muscle fiber. A higher vagal tone delays the increase in the sympathetic tone during physical exertion. The regulatory range of heart rate, contractility, diastolic function, and blood pressure is increased. In addition, adaptation results in functional and structural changes in the vascular system. Cardiocirculatory work is economized, and maximum performance and oxygen uptake are improved. Endurance training exceeding an individual limit causes harmonic enlargement and hypertrophy of the

  8. Passion and Pacing in Endurance Performance

    Science.gov (United States)

    Schiphof-Godart, Lieke; Hettinga, Florentina J.

    2017-01-01

    Endurance sports are booming, with sports passionates of varying skills and expertise battering city streets and back roads on their weekly or daily exercise rounds. The investments required for performing in endurance exercise are nevertheless considerable, and passion for their sport might explain the efforts endurance athletes are willing to make. Passion may be defined as a strong motivational force and as such might be related to the neurophysiological basis underlying the drive to exercise. A complex relationship between the brain and other systems is responsible for athletes' exercise behavior and thus performance in sports. We anticipate important consequences of athletes' short term choices, for example concerning risk taking actions, on long term outcomes, such as injuries, overtraining and burnout. We propose to consider athletes' type of passion, in combination with neurophysiological parameters, as an explanatory factor inunderstanding the apparent disparity in the regulation of exercise intensity during endurance sports. Previous research has demonstrated that athletes can be passionate toward their sport in either a harmonious or an obsessive way. Although both lead to considerable investments and therefore often to successful performances, obsessive passion may affect athlete well-being and performance on the long run, due to the corresponding inflexible exercise behavior. In this perspective we will thus examine the influence of passion in sport on athletes' short term and long term decision-making and exercise behavior, in particular related to the regulation of exercise intensity, and discuss the expected long term effects of both types of passion for sport. PMID:28265245

  9. Six Sigma: Problems, Limitations, Critical Success Factors and Future Prospects

    Directory of Open Access Journals (Sweden)

    Paulo Mazieiro Pohlmann

    2015-12-01

    Full Text Available Six Sigma is a business strategy based on objective decision making and problem solving in order to achieve, maintain and maximize business success through understanding and meeting the needs of customers. The visualization of this methodology as a powerful tool in reducing variability and improving quality led to the interest in performing this bibliographical study, whose purpose was to assess the critical success factors and future prospects of this managerial system. A survey was conducted in order to discover the main critical success factors of the implementation of the methodology in organizations, among which stood out the proper selection of projects, connecting the project with the business strategy, customer focus, financial, human and infrastructure resources, the involvement of senior management, professional training, and cultural change.

  10. Explanatory factors of female entrepreneurship and limiting elements

    Directory of Open Access Journals (Sweden)

    Carmina Pérez-Pérez

    2016-06-01

    Full Text Available Researches on entrepreneurship from a gender perspective reveal significant differences not only between the levels of participation of men and women in business, but also between the orientations, motives and business opportunities for both. Based on this fact, the following investigation is performed, whose objective is twofold: firstly, to know what are the aspects that influence the entrepreneurship of women and secondly, to identify what factors determine and/or difficult the creation and development of business that they undertake. To achieve both, it is reviewed, first, the literature on this subject and, second, are exposed the main results of the qualitative analysis with Atlas.ti from interviews with a group of Spanish entrepreneurs.

  11. Phosphorus as a limiting factor on sustainable greywater irrigation.

    Science.gov (United States)

    Turner, Ryan D R; Will, Geoffrey D; Dawes, Les A; Gardner, Edward A; Lyons, David J

    2013-07-01

    Water reuse through greywater irrigation has been adopted worldwide and has been proposed as a potential sustainable solution to increased water demands. Despite widespread adoption, there is limited domestic knowledge of greywater reuse. There is no pressure to produce low-level phosphorus products and current guidelines and legislation, such as those in Australia, may be inadequate due to the lack of long-term data to provide a sound scientific basis. Research has clearly identified phosphorus as a potential environmental risk to waterways from many forms of irrigation. To assess the sustainability of greywater irrigation, this study compared four residential lots that had been irrigated with greywater for four years and adjacent non-irrigated lots that acted as controls. Each lot was monitored for the volume of greywater applied and selected physic-chemical water quality parameters and soil chemistry profiles were analysed. The non-irrigated soil profiles showed low levels of phosphorus and were used as controls. The Mechlich3 Phosphorus ratio (M3PSR) and Phosphate Environmental Risk Index (PERI) were used to determine the environmental risk of phosphorus leaching from the irrigated soils. Soil phosphorus concentrations were compared to theoretical greywater irrigation loadings. The measured phosphorus soil concentrations and the estimated greywater loadings were of similar magnitude. Sustainable greywater reuse is possible; however incorrect use and/or lack of understanding of how household products affect greywater can result in phosphorus posing a significant risk to the environment.

  12. Efficiency limit factor analysis for the Francis-99 hydraulic turbine

    Science.gov (United States)

    Zeng, Y.; Zhang, L. X.; Guo, J. P.; Guo, Y. K.; Pan, Q. L.; Qian, J.

    2017-01-01

    The energy loss in hydraulic turbine is the most direct factor that affects the efficiency of the hydraulic turbine. Based on the analysis theory of inner energy loss of hydraulic turbine, combining the measurement data of the Francis-99, this paper calculates characteristic parameters of inner energy loss of the hydraulic turbine, and establishes the calculation model of the hydraulic turbine power. Taken the start-up test conditions given by Francis-99 as case, characteristics of the inner energy of the hydraulic turbine in transient and transformation law are researched. Further, analyzing mechanical friction in hydraulic turbine, we think that main ingredients of mechanical friction loss is the rotation friction loss between rotating runner and water body, and defined as the inner mechanical friction loss. The calculation method of the inner mechanical friction loss is given roughly. Our purpose is that explore and research the method and way increasing transformation efficiency of water flow by means of analysis energy losses in hydraulic turbine.

  13. Socio-demographic factors related to functional limitations and care dependency among older Egyptians

    NARCIS (Netherlands)

    Boggatz, Thomas; Farid, Tamer; Mohammedin, Ahmed; Dijkstra, Ate; Lohrmann, Christa; Dassen, Theo

    P>Title. Socio-demographic factors related to functional limitations and care dependency among older Egyptians. Aim. This paper is a report of a study determining the relationship of socio-demographic factors to functional limitations and care dependency among older care recipients and non-care

  14. Socio-demographic factors related to functional limitations and care dependency among older Egyptians

    NARCIS (Netherlands)

    Boggatz, Thomas; Farid, Tamer; Mohammedin, Ahmed; Dijkstra, Ate; Lohrmann, Christa; Dassen, Theo

    2010-01-01

    P>Title. Socio-demographic factors related to functional limitations and care dependency among older Egyptians. Aim. This paper is a report of a study determining the relationship of socio-demographic factors to functional limitations and care dependency among older care recipients and non-care reci

  15. Development of management quality system for metallurgical enterprise based on Balanced Scorecard with limiting factors

    Directory of Open Access Journals (Sweden)

    Galina Ledneva

    2009-12-01

    Full Text Available The article considers inefficiency of the existing quality management systems (QMS based on standards ISO series 9000. The authors offer integrated QMS with limiting factors on Balanced Scorecard. The Balanced Scorecard with limiting factors helps to efficiently direct process of continuous improvement and achieve top-priority criteria in quality management domain.

  16. Arctigenin efficiently enhanced sedentary mice treadmill endurance.

    Science.gov (United States)

    Tang, Xuan; Zhuang, Jingjing; Chen, Jing; Yu, Liang; Hu, Lihong; Jiang, Hualiang; Shen, Xu

    2011-01-01

    Physical inactivity is considered as one of the potential risk factors for the development of type 2 diabetes and other metabolic diseases, while endurance exercise training could enhance fat oxidation that is associated with insulin sensitivity improvement in obesity. AMP-activated protein kinase (AMPK) as an energy sensor plays pivotal roles in the regulation of energy homeostasis, and its activation could improve glucose uptake, promote mitochondrial biogenesis and increase glycolysis. Recent research has even suggested that AMPK activation contributed to endurance enhancement without exercise. Here we report that the natural product arctigenin from the traditional herb Arctium lappa L. (Compositae) strongly increased AMPK phosphorylation and subsequently up-regulated its downstream pathway in both H9C2 and C2C12 cells. It was discovered that arctigenin phosphorylated AMPK via calmodulin-dependent protein kinase kinase (CaMKK) and serine/threonine kinase 11(LKB1)-dependent pathways. Mice treadmill based in vivo assay further indicated that administration of arctigenin improved efficiently mice endurance as reflected by the increased fatigue time and distance, and potently enhanced mitochondrial biogenesis and fatty acid oxidation (FAO) related genes expression in muscle tissues. Our results thus suggested that arctigenin might be used as a potential lead compound for the discovery of the agents with mimic exercise training effects to treat metabolic diseases.

  17. Arctigenin Efficiently Enhanced Sedentary Mice Treadmill Endurance

    Science.gov (United States)

    Chen, Jing; Yu, Liang; Hu, Lihong; Jiang, Hualiang; Shen, Xu

    2011-01-01

    Physical inactivity is considered as one of the potential risk factors for the development of type 2 diabetes and other metabolic diseases, while endurance exercise training could enhance fat oxidation that is associated with insulin sensitivity improvement in obesity. AMP-activated protein kinase (AMPK) as an energy sensor plays pivotal roles in the regulation of energy homeostasis, and its activation could improve glucose uptake, promote mitochondrial biogenesis and increase glycolysis. Recent research has even suggested that AMPK activation contributed to endurance enhancement without exercise. Here we report that the natural product arctigenin from the traditional herb Arctium lappa L. (Compositae) strongly increased AMPK phosphorylation and subsequently up-regulated its downstream pathway in both H9C2 and C2C12 cells. It was discovered that arctigenin phosphorylated AMPK via calmodulin-dependent protein kinase kinase (CaMKK) and serine/threonine kinase 11(LKB1)-dependent pathways. Mice treadmill based in vivo assay further indicated that administration of arctigenin improved efficiently mice endurance as reflected by the increased fatigue time and distance, and potently enhanced mitochondrial biogenesis and fatty acid oxidation (FAO) related genes expression in muscle tissues. Our results thus suggested that arctigenin might be used as a potential lead compound for the discovery of the agents with mimic exercise training effects to treat metabolic diseases. PMID:21887385

  18. Arctigenin efficiently enhanced sedentary mice treadmill endurance.

    Directory of Open Access Journals (Sweden)

    Xuan Tang

    Full Text Available Physical inactivity is considered as one of the potential risk factors for the development of type 2 diabetes and other metabolic diseases, while endurance exercise training could enhance fat oxidation that is associated with insulin sensitivity improvement in obesity. AMP-activated protein kinase (AMPK as an energy sensor plays pivotal roles in the regulation of energy homeostasis, and its activation could improve glucose uptake, promote mitochondrial biogenesis and increase glycolysis. Recent research has even suggested that AMPK activation contributed to endurance enhancement without exercise. Here we report that the natural product arctigenin from the traditional herb Arctium lappa L. (Compositae strongly increased AMPK phosphorylation and subsequently up-regulated its downstream pathway in both H9C2 and C2C12 cells. It was discovered that arctigenin phosphorylated AMPK via calmodulin-dependent protein kinase kinase (CaMKK and serine/threonine kinase 11(LKB1-dependent pathways. Mice treadmill based in vivo assay further indicated that administration of arctigenin improved efficiently mice endurance as reflected by the increased fatigue time and distance, and potently enhanced mitochondrial biogenesis and fatty acid oxidation (FAO related genes expression in muscle tissues. Our results thus suggested that arctigenin might be used as a potential lead compound for the discovery of the agents with mimic exercise training effects to treat metabolic diseases.

  19. Nutrition for endurance sports: marathon, triathlon, and road cycling.

    Science.gov (United States)

    Jeukendrup, Asker E

    2011-01-01

    Endurance sports are increasing in popularity and athletes at all levels are looking for ways to optimize their performance by training and nutrition. For endurance exercise lasting 30 min or more, the most likely contributors to fatigue are dehydration and carbohydrate depletion, whereas gastrointestinal problems, hyperthermia, and hyponatraemia can reduce endurance exercise performance and are potentially health threatening, especially in longer events (>4 h). Although high muscle glycogen concentrations at the start may be beneficial for endurance exercise, this does not necessarily have to be achieved by the traditional supercompensation protocol. An individualized nutritional strategy can be developed that aims to deliver carbohydrate to the working muscle at a rate that is dependent on the absolute exercise intensity as well as the duration of the event. Endurance athletes should attempt to minimize dehydration and limit body mass losses through sweating to 2-3% of body mass. Gastrointestinal problems occur frequently, especially in long-distance races. Problems seem to be highly individual and perhaps genetically determined but may also be related to the intake of highly concentrated carbohydrate solutions, hyperosmotic drinks, as well as the intake of fibre, fat, and protein. Hyponatraemia has occasionally been reported, especially among slower competitors with very high intakes of water or other low sodium drinks. Here I provide a comprehensive overview of recent research findings and suggest several new guidelines for the endurance athlete on the basis of this. These guidelines are more detailed and allow a more individualized approach.

  20. Endurance capacity and neuromuscular fatigue following high- vs moderate-intensity endurance training: A randomized trial.

    Science.gov (United States)

    O'Leary, T J; Collett, J; Howells, K; Morris, M G

    2017-02-16

    High-intensity exercise induces significant central and peripheral fatigue; however, the effect of endurance training on these mechanisms of fatigue is poorly understood. We compared the effect of cycling endurance training of disparate intensities on high-intensity exercise endurance capacity and the associated limiting central and peripheral fatigue mechanisms. Twenty adults were randomly assigned to 6 weeks of either high-intensity interval training (HIIT, 6-8×5 minutes at halfway between lactate threshold and maximal oxygen uptake [50%Δ]) or volume-matched moderate-intensity continuous training (CONT, ~60-80 minutes at 90% lactate threshold). Two time to exhaustion (TTE) trials at 50%Δ were completed pre- and post-training to assess endurance capacity; the two post-training trials were completed at the pretraining 50%Δ (same absolute intensity) and the "new" post-training 50%Δ (same relative intensity). Pre- and post-exercise responses to femoral nerve and motor cortex stimulation were examined to determine peripheral and central fatigue, respectively. HIIT resulted in greater increases in TTE at the same absolute and relative intensities as pre-training (148% and 43%, respectively) compared with CONT (38% and -4%, respectively) (P≤.019). Compared with pre-training, HIIT increased the level of potentiated quadriceps twitch reduction (-34% vs -43%, respectively, P=.023) and attenuated the level of voluntary activation reduction (-7% vs -3%, respectively, P=.047) following the TTE trial at the same relative intensity. There were no other training effects on neuromuscular fatigue development. This suggests that central fatigue resistance contributes to enhanced high-intensity exercise endurance capacity after HIIT by allowing greater performance to be extruded from the muscle. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Iron and the endurance athlete.

    Science.gov (United States)

    Hinton, Pamela S

    2014-09-01

    Iron is a trace mineral that is highly significant to endurance athletes. Iron is critical to optimal athletic performance because of its role in energy metabolism, oxygen transport, and acid-base balance. Endurance athletes are at increased risk for suboptimal iron status, with potential negative consequences on performance, because of the combination of increased iron needs and inadequate dietary intake. This review paper summarizes the role of iron in maximal and submaximal exercise and describes the effects of iron deficiency on exercise performance. Mechanisms that explain the increased risk of iron deficiency in endurance athletes, including exercise-associated inflammation and hepcidin release on iron sequestration, are described. Information on screening athletes for iron deficiency is presented, and suggestions to increase iron intake through diet modification or supplemental iron are provided.

  2. Demographics and limiting factors of tundra nesting birds at the Canning River products

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Products resulting from the Arctic NWR project "Demographics and limiting factors of tundra nesting birds at the Canning River" (PRIMR survey FF07RARC00-010).

  3. Enduring Issues In Educational Assessment

    Science.gov (United States)

    Della-Piana, Gabriel M.

    2008-01-01

    Assessments were an important tool recommended by "A Nation at Risk;" however, a generation after that report, many of the problems with student assessment still remain. This article offers brief reflections on three somewhat overlapping but enduring issues in educational assessment: validity, construct underrepresentation in outcome measures in…

  4. Soccer Endurance Development in Professionals

    NARCIS (Netherlands)

    Roescher, C. R.; Elferink-Gemser, M. T.; Huijgen, B. C. H.; Visscher, C.

    2010-01-01

    The development of intermittent endurance capacity, its underlying mechanisms and role in reaching professional level in soccer was investigated. The sample included 130 talented youth soccer players aged 14-18, who became professional (n = 53) or non-professional (n = 77) players in adulthood. In t

  5. Soccer Endurance Development in Professionals

    NARCIS (Netherlands)

    Roescher, C. R.; Elferink-Gemser, M. T.; Huijgen, B. C. H.; Visscher, C.

    The development of intermittent endurance capacity, its underlying mechanisms and role in reaching professional level in soccer was investigated. The sample included 130 talented youth soccer players aged 14-18, who became professional (n = 53) or non-professional (n = 77) players in adulthood. In

  6. Food selection for endurance sports.

    Science.gov (United States)

    Houtkooper, L

    1992-09-01

    1) The body requires at least 40 nutrients that are classified into six groups: protein, carbohydrate, fat, vitamin, mineral, and water. These nutrients cannot be made in the body and so they must be supplied from solid or liquid foods. 2) Fat, carbohydrate, and protein contain energy that is measured in units called kilocalories. Alcohol also contains kilocalories, but is not a recommended energy source for endurance exercise. 3) Foods in endurance sports training programs should provide adequate fluids to prevent dehydration; energy intake that is high in carbohydrate, low in fat, adequate in protein, and that maintains desirable body weight and desirable proportions of fat and lean weight; and sufficient amounts of vitamins and minerals. 4) Six categories of food types form the fundamentals of good diets for endurance exercise training and include: fruits, vegetables, grains-legumes, lean meats, low-fat milk products, and fats-sweets. Vegetarian diets include all food type categories except meat and/or milk products. 5) Fat and carbohydrate content of foods in each food type category varies greatly because of how foods are prepared. 6) The Food Pyramid and Sports Food Swap are guides for selecting foods that provide recommended amounts of essential nutrients for endurance exercise. 7) Before, during, and after endurance exercise, food intake should include adequate amounts of easily digestible, high carbohydrate foods that are familiar and psychologically satisfying. 8) Easily digestible high carbohydrate liquid or solid foods should be eaten soon after exercise is stopped to maximize rates of glycogen replacement. 9) Dehydration can be prevented by adequate fluid intake before, during, and after exercise. 10) Any food plan should be tested before a competition to find out how well that plan works for an athlete.

  7. Effects of Resistance Training on Muscle Strength, Endurance, and Motor Unit According to Ciliary Neurotrophic Factor Polymorphism in Male College Students

    OpenAIRE

    Ae-Rim Hong, Sang-Min Hong, Yun-A Shin

    2014-01-01

    Changes in muscle mass and strength across the adult age span are variable and related to the ciliary neurotrophic factor (CNTF) genotype. In particular, a single CNTF haplotype (1357 G→A) is important for neuronal and muscular developments and may be associated with muscle strength response to resistance training. We examined whether CNTF genotype differentially influences the effect of resistance training on neuromuscular improvement in male college students. Resistance training of the uppe...

  8. 14 CFR 35.39 - Endurance test.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Endurance test. 35.39 Section 35.39... STANDARDS: PROPELLERS Tests and Inspections § 35.39 Endurance test. Endurance tests on the propeller system... propellers must be subjected to one of the following tests: (1) A 50-hour flight test in level flight or...

  9. 14 CFR 33.49 - Endurance test.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Endurance test. 33.49 Section 33.49... STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.49 Endurance test. (a) General. Each engine must be subjected to an endurance test that includes a total of 150 hours of...

  10. 14 CFR 33.87 - Endurance test.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Endurance test. 33.87 Section 33.87... STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.87 Endurance test. (a) General. Each engine must be subjected to an endurance test that includes a total of at least 150 hours of...

  11. [Improved performance in endurance sports through acupuncture].

    Science.gov (United States)

    Benner, Stefan; Benner, K

    2010-09-01

    In many years of experience in treating athletes with acupuncture, I often had the impression that athletes in endurance sports showed improved performances after such treatments. In order to scientifically verify these impressions, I performed a field test with three groups of runners of different performance levels preparing for a marathon. The first group was given acupuncture, the second a placebo, with the third being the control group. After their maximum pulse rates were recorded, the runners were asked to run 5000m four times in 4 weeks at 75 % of their maximum pulse rate. Their pulse rates were measured for each runner at the finish of the run, and subsequently, one, two and five minutes after the run. Based on these data, the complexity factor (running time multiplied by the respective pulse rate) was calculated for all four recorded pulse rates for each run and each runner. All groups showed statistically significant enhancements in their running times and their complexity factors, but in the case of the runners treated with acupuncture, the improvements were highly significant. Therefore, the field test proves that acupuncture has a significant impact on the performance of the athletes in endurance sports.

  12. Crew Endurance Management Practices: A Guide for Maritime Operations

    Science.gov (United States)

    2003-01-01

    Watchkeeping for Seafarers ( STCW ) regarding hours of work and rest. The fundamental purpose of this guide is to provide managers, captains, department...should use this information, along with the guidelines provided in OPA 90 and STCW : • To identify risk factors affecting crew endurance in specific

  13. Natural SUSY endures

    Energy Technology Data Exchange (ETDEWEB)

    Papucci, Michele; Ruderman, Joshua T. [Lawrence Berkeley National Laboratory, CA (United States). Theoretical Physics Group; California Univ., Berkeley, CA (United States). Dept. of Physics; Weiler, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); European Organization for Nuclear Research, Geneva (Switzerland). Theoretical Physics Div.

    2011-10-31

    The first 1 fb{sup -1} of LHC searches have set impressive limits on new colored particles decaying to missing energy. We address the implication of these searches for naturalness in supersymmetry (SUSY). General bottom-up considerations of natural electroweak symmetry breaking show that higgsinos, stops, and the gluino should not be too far above the weak scale. The rest of the spectrum, including the squarks of the first two generations, can be heavier and beyond the current LHC reach. We have used collider simulations to determine the limits that all of the 1 fb{sup -1} searches pose on higgsinos, stops, and the gluino. We find that stops and the left-handed sbottom are starting to be constrained and must be heavier than about 200-300 GeV when decaying to higgsinos. The gluino must be heavier than about 600-800 GeV when it decays to stops and sbottoms. While these findings point toward scenarios with a lighter third generation split from the other squarks, we do find that moderately-tuned regions remain, where the gluino is just above 1 TeV and all the squarks are degenerate and light. Among all the searches, jets plus missing energy and same-sign dileptons often provide the most powerful probes of natural SUSY. Overall, our results indicate that natural SUSY has survived the first 1 fb{sup -1} of data. The LHC is now on the brink of exploring the most interesting region of SUSY parameter space. (orig.)

  14. Hodgkin's Lymphoma in an elite endurance athlete.

    Science.gov (United States)

    Schumacher, Yorck Olaf; Muser, Klaus; Hirschberger, Barbara; Roecker, Kai; Dickhuth, Hans Herrmann; Pottgiesser, Torben

    2008-03-01

    Cancer is a life-threatening condition. We describe the case of a 22-yr-old world-class endurance athlete who presented with mild local lymphadenopathy but without any systemic complaints or impaired performance. He was subsequently diagnosed with stage III A (S) Hodgkin's lymphoma. A complete physiological workup before the diagnosis revealed high aerobic capacity. Immediately after six courses of escalated BEACOPP chemotherapy in an identical test setting, aerobic capacity was markedly reduced (-42%), mainly because of a decrease in total hemoglobin mass (-37%), despite maintaining a certain amount of endurance training. Other potentially performance-limiting systems such as heart, lung, or aerobic metabolism did not show any signs of impairment. Two months after chemotherapy, the athlete had recovered his hemoglobin mass, and his aerobic performance was almost back to pretherapy levels. This case illustrates that advanced malignancies can be present in elite athletes without affecting performance, and that aerobic capacity can be regained within a short time after systemic chemotherapy.

  15. Effects of endurance and endurance-strength exercise on biochemical parameters of liver function in women with abdominal obesity.

    Science.gov (United States)

    Skrypnik, Damian; Ratajczak, Marzena; Karolkiewicz, Joanna; Mądry, Edyta; Pupek-Musialik, Danuta; Hansdorfer-Korzon, Rita; Walkowiak, Jarosław; Jakubowski, Hieronim; Bogdański, Paweł

    2016-05-01

    Obesity is a risk factor of nonalcoholic fatty liver disease. Although the standard therapy for obesity involves physical exercise, well-planned studies of the changes in liver function in response to different exercise intensities in obese subjects are scarce. The aim of the present study was to examine a question of how does exercise mode affect the liver function. 44 women with abdominal obesity were randomized into two exercise groups: endurance (group A) and endurance-strength (group B). Women in each group exercised for 60min 3 times/week for a 3-month period. Markers of liver function: serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltranspeptidase (GGT), alkaline phosphatase (ALP) activities, and bilirubin levels were quantified. We found significant differences in ALT (pexercise. Blood ALT and AST tended to decrease in group B, increase in group A. Significant reduction in serum GGT level after exercise in both groups was observed (pexercise led to changes in serum ALP activity and total or direct bilirubin level. However, endurance-strength training resulted in significant decreases in serum indirect bilirubin (pexercise (group B). The mode of exercise does matter: endurance-strength exercise led to a greater improvement, compared to endurance exercise, in the liver function in women with abdominal obesity. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  16. Understanding early contextual and parental risk factors for the development of limited prosocial emotions

    OpenAIRE

    Waller, Rebecca; Shaw, Daniel S.; Forbes, Erika E.; Hyde, Luke W.

    2015-01-01

    A growing body of evidence suggests that parenting influences the development of youth callous unemotional (CU) behavior. However, less is known about the effects of parenting or contextual risk factors on ‘limited prosocial emotions’ (LPE), a recent conceptualization of CU behavior added to the DSM-5. We focused on LPE at ages 10–12 and age 20 among low income, urban males (N = 310), and examined potential developmental precursors, including contextual risk factors assessed during infancy an...

  17. Functional limitation and associated factors in outpatients with ankylosing spondylitis in Southwest China.

    Science.gov (United States)

    Song, Yuqing; Wang, Chen; Chen, Hong

    2017-04-01

    Functional limitation is often complained by patients with ankylosing spondylitis (AS). With a rising number of patients suffering from AS, there are a limited number of reports focusing on functional limitation of AS in Chinese patients. This study was conducted to investigate the level of functional limitation and explore its associations with demographic, disease-related factors. A total of 303 AS outpatients were recruited in this cross-sectional study from a tertiary general hospital in Southwest China. Functional limitation was measured by the Bath Ankylosing Spondylitis Functional Index (BASFI). Other data were collected by the following questionnaires: the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the Bath Ankylosing Spondylitis Patient Global Score (BAS-G), and the Pittsburgh Sleep Quality Index Questionnaire (PSQI). Finally, 295 outpatients with AS completed this survey. The median BASFI was 0.80. Worse function limitation was found in outpatients with extra-spinal manifestation, older age, lower household income, more back pain, higher disease activity and morning stiffness, poorer sleep, and worse patient's well-being (all P < 0.05). Multivariate regression analysis indicated that patient's well-being (P < 0.001), disease activity (P < 0.001), and disease duration (P < 0.05) were the positive predictors of functional limitation. AS outpatients in Southwest China had a mild level of functional limitation. The factors associated with functional limitation included disease duration, disease activity, and patients' well-being, which should be taken into consideration when assessing functional limitation of AS outpatients. Besides, more comprehensive and targeted interventions should be conducted for AS patients as early as possible, which will be effective to improve functional outcome.

  18. Common problems in endurance athletes.

    Science.gov (United States)

    Cosca, David D; Navazio, Franco

    2007-07-15

    Endurance athletes alternate periods of intensive physical training with periods of rest and recovery to improve performance. An imbalance caused by overly intensive training and inadequate recovery leads to a breakdown in tissue reparative mechanisms and eventually to overuse injuries. Tendon overuse injury is degenerative rather than inflammatory. Tendinopathy is often slow to resolve and responds inconsistently to anti-inflammatory agents. Common overuse injuries in runners and other endurance athletes include patellofemoral pain syndrome, iliotibial band friction syndrome, medial tibial stress syndrome, Achilles tendinopathy, plantar fasciitis, and lower extremity stress fractures. These injuries are treated with relative rest, usually accompanied by a rehabilitative exercise program. Cyclists may benefit from evaluation on their bicycles and subsequent adjustment of seat height, cycling position, or pedal system. Endurance athletes also are susceptible to exercise-associated medical conditions, including exercise-induced asthma, exercise-associated collapse, and overtraining syndrome. These conditions are treatable or preventable with appropriate medical intervention. Dilutional hyponatremia is increasingly encountered in athletes participating in marathons and triathlons. This condition is related to overhydration with hypotonic fluids and may be preventable with guidance on appropriate fluid intake during competition.

  19. Pion Form Factor in Chiral Limit of Hard-Wall AdS/QCD Model

    Energy Technology Data Exchange (ETDEWEB)

    Anatoly Radyushkin; Hovhannes Grigoryan

    2007-12-01

    We develop a formalism to calculate form factor and charge density distribution of pion in the chiral limit using the holographic dual model of QCD with hard-wall cutoff. We introduce two conjugate pion wave functions and present analytic expressions for these functions and for the pion form factor. They allow to relate such observables as the pion decay constant and the pion charge electric radius to the values of chiral condensate and hard-wall cutoff scale. The evolution of the pion form factor to large values of the momentum transfer is discussed, and results are compared to existing experimental data.

  20. Colorado Plateau Rapid Ecoregion Assessment Conservation Elements - Terrestrial Species: Greater Sage-Grouse Limiting Factors

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — This map presents limiting factors for Greater Sage-grouse for an area in the northern part of the ecoregion. This was used for the sage-grouse insert in the final...

  1. Factors that Limit and Enable Preschool-Aged Children's Physical Activity on Child Care Centre Playgrounds

    Science.gov (United States)

    Coleman, Bianca; Dyment, Janet E.

    2013-01-01

    The incidence of childhood obesity amongst preschool-aged children has increased dramatically in recent years and can be attributed, in part, to a lack of physical activity amongst children in this age group. This study explores the social factors that stand to limit and/or enable children's physical activity opportunities in outdoor settings in…

  2. What is the most prominent factor limiting photosynthesis in different layers of a greenhouse cucumber canopy?

    NARCIS (Netherlands)

    Chen, T.W.; Henke, M.; Visser, de P.H.B.; Buck-Sorlin, G.H.; Wiechers, D.; Kahlen, K.; Stützel, H.

    2014-01-01

    Background and Aims Maximizing photosynthesis at the canopy level is important for enhancing crop yield, and this requires insights into the limiting factors of photosynthesis. Using greenhouse cucumber (Cucumis sativus) as an example, this study provides a novel approach to quantify different compo

  3. The Nutraceutical Bioavailability Classification Scheme: Classifying Nutraceuticals According to Factors Limiting their Oral Bioavailability.

    Science.gov (United States)

    McClements, David Julian; Li, Fang; Xiao, Hang

    2015-01-01

    The oral bioavailability of a health-promoting dietary component (nutraceutical) may be limited by various physicochemical and physiological phenomena: liberation from food matrices, solubility in gastrointestinal fluids, interaction with gastrointestinal components, chemical degradation or metabolism, and epithelium cell permeability. Nutraceutical bioavailability can therefore be improved by designing food matrices that control their bioaccessibility (B*), absorption (A*), and transformation (T*) within the gastrointestinal tract (GIT). This article reviews the major factors influencing the gastrointestinal fate of nutraceuticals, and then uses this information to develop a new scheme to classify the major factors limiting nutraceutical bioavailability: the nutraceutical bioavailability classification scheme (NuBACS). This new scheme is analogous to the biopharmaceutical classification scheme (BCS) used by the pharmaceutical industry to classify drug bioavailability, but it contains additional factors important for understanding nutraceutical bioavailability in foods. The article also highlights potential strategies for increasing the oral bioavailability of nutraceuticals based on their NuBACS designation (B*A*T*).

  4. Relationship of changes in maximal and submaximal aerobic fitness to changes in cardiovascular disease and non-insulin-dependent diabetes mellitus risk factors with endurance training: the HERITAGE Family Study.

    Science.gov (United States)

    Wilmore, J H; Green, J S; Stanforth, P R; Gagnon, J; Rankinen, T; Leon, A S; Rao, D C; Skinner, J S; Bouchard, C

    2001-11-01

    The purpose of this study was to determine the relationship between changes in maximal oxygen uptake (VO2 max) and submaximal markers of aerobic fitness and changes in risk factors for cardiovascular disease (CVD) and non-insulin-dependent diabetes mellitus (NIDDM) consequent to a 20-week endurance training program. The 502 participants in this study were healthy and previously sedentary men (n = 250) and women (n = 252) of varying age (17 to 65 years) and race (blacks n = 142; whites n = 360) who had completed the HERITAGE Family Study testing and training protocol. Following baseline measurements, participants trained on cycle ergometers 3 days/week for a total of 60 exercise sessions starting at the heart rate (HR) associated with 55% of VO2 max for 30 minutes/session. This was progressively increased to the HR associated with 75% of VO2 max for 50 minutes/session, which was maintained during the last 6 weeks. VO2 max, heart rate at 50 W, power output at 60% of VO2 max, lipids and lipoproteins, resting blood pressure, body composition including abdominal fat (computed tomography [CT] scan), and blood glucose and insulin at rest and at peak following an intravenous glucose tolerance test (IVGTT) were determined both before and after training. Following training, there were significant increases in VO2 max (16%) and the power output at 60% of VO2 max and a significant decrease in HR at 50 W. These changes in markers of aerobic fitness were significantly correlated only to the changes in the body composition variables and the lipids and lipoproteins. Further, there was considerable individual variation in response for all variables studied. Finally, when risk factor data were analyzed by quartile of change in VO2 max, there were few significant relationships. It is concluded that there is a significant relationship between changes in markers of aerobic fitness and changes in several risk factors for CVD and NIDDM. However, the magnitude of these relationships is

  5. Factors limiting the establishment of canopy-forming algae on artificial structures

    Science.gov (United States)

    Cacabelos, Eva; Martins, Gustavo M.; Thompson, Richard; Prestes, Afonso C. L.; Azevedo, José Manuel N.; Neto, Ana I.

    2016-11-01

    Macroalgal canopies are important ecosystem engineers, contributing to coastal productivity and supporting a rich assemblage of associated flora and fauna. However, they are often absent from infrastructures such as coastal defences and there has been a worldwide decline in their distribution in urbanised coastal areas. The macroalga Fucus spiralis is the only high-shore canopy forming species present in the Azores. It is widely distributed in the archipelago but is never found on coastal infrastructures. Here we evaluate factors that may potentially limit its establishment on artificial structures. A number of observational and manipulative experiments were used to test the hypotheses that: (i) limited-dispersal ability limits the colonisation of new plants onto artificial structures, (ii) vertical substratum slope negatively influences the survivorship of recruits, and (iii) vertical substratum slope also negatively influences the survivorship and fitness of adults. Results showed that the limited dispersal from adult plants may be a more important factor than slope in limiting the species ability to colonise coastal infrastructures, since the vertical substratum slope does not affect its fitness or survivorship.

  6. Psychosocial factors at work and the development of mobility limitations among adults in Denmark

    DEFF Research Database (Denmark)

    Hansen, Åse Marie; Darsø, Lilie; Manty, Minna

    2014-01-01

    : This study is based on data from 2952 middle-aged men and women without mobility limitations in 2000. Results: We found increased risk of incident mobility limitations during 6-year follow up among men who often perceived high work pace (OR 5.45, 95% CI 1.21-24.52) vs. never, who only sometimes or....../never perceived the work to be meaningful (OR 6.54, 95% CI 1.55-27.55) vs. always, and who sometimes perceived high emotional demands at work (OR 7.85, 95% CI 1.78-34.65) vs. never. Among women, lower risk of incident mobility limitations was observed among those who in 2000 perceived high work pace sometimes (OR......Aim: Psychosocial factors in the working environment have been shown to be associated with mobility limitations, but this has not yet been confirmed in a Danish population. We aimed to examine how psychosocial factors at work are related to developing mobility limitations in Denmark. Methods...

  7. New Precision Limit on the Strange Vector Form Factors of the Proton

    CERN Document Server

    Ahmed, Z; Aniol, K A; Armstrong, D S; Arrington, J; Baturin, P; Bellini, V; Benesch, J; Beminiwattha, R; Benmokhtar, F; Canan, M; Camsonne, A; Cates, G D; Chen, J -P; Chudakov, E; Cisbani, E; Dalton, M M; de Jager, C W; De Leo, R; Deconinck, W; Decowski, P; Deng, X; Deur, A; Dutta, C; Franklin, G B; Friend, M; Frullani, S; Garibaldi, F; Giusa, A; Glamazdin, A; Golge, S; Grimm, K; Hansen, O; Higinbotham, D W; Holmes, R; Holmstrom, T; Huang, J; Huang, M; Hyde, C E; Jen, C M; Jin, G; Jones, D; Kang, H; King, P; Kowalski, S; Kumar, K S; Lee, J H; LeRose, J J; Liyanage, N; Long, E; McNulty, D; Margaziotis, D; Meddi, F; Meekins, D G; Mercado, L; Meziani, Z -E; Michaels, R; Munoz-Camacho, C; Mihovilovic, M; Muangma, N; Myers, K E; Nanda, S; Narayan, A; Nelyubin, V; Nuruzzaman,; Oh, Y; Pan, K; Parno, D; Paschke, K D; Phillips, S K; Qian, X; Qiang, Y; Quinn, B; Rakhman, A; Reimer, P E; Rider, K; Riordan, S; Roche, J; Rubin, J; Russo, G; Saenboonruang, K; Saha, A; Sawatzky, B; Silwal, R; Sirca, S; Souder, P A; Sperduto, M; Subedi, R; Suleiman, R; Sulkosky, V; Sutera, C M; Tobias, W A; Urciuoli, G M; Waidyawansa, B; Wang, D; Wexler, J; Wilson, R; Wojtsekhowski, B; Zhan, X; Yan, X; Yao, H; Ye, L; Zhao, B; Zheng, X

    2011-01-01

    The parity-violating cross-section asymmetry in the elastic scattering of polarized electrons from unpolarized protons has been measured at a four-momentum transfer squared Q2 = 0.624 GeV and beam energy E =3.48 GeV to be A_PV = -23.80 +/- 0.78 (stat) +/- 0.36 (syst) parts per million. This result is consistent with zero contribution of strange quarks to the combination of electric and magnetic form factors G_E^s + 0.517 G_M^s = 0.003 +/- 0.010 (stat) +/- 0.004 (syst) +/- 0.009 (ff), where the third error is due to the limits of precision on the electromagnetic form factors and radiative corrections. With this measurement, the world data on strange contributions to nucleon form factors are seen to be consistent with zero and not more than a few percent of the proton form factors.

  8. The adiabatic limit of the exact factorization of the electron-nuclear wave function

    CERN Document Server

    Eich, Florian G

    2016-01-01

    We propose a procedure to analyze the relation between the exact factorization of the electron-nuclear wave function and the Born-Oppenheimer approximation. We define the adiabatic limit as the limit of infinite nuclear mass. To this end, we introduce a unit system that singles out the dependence on the electron-nuclear mass ratio of each term appearing in the equations of the exact factorization. We observe how non-adiabatic effects induced by the coupling to the nuclear motion affect electronic properties and we analyze the leading term, connecting it to the classical nuclear momentum. Its dependence on the mass ratio is tested numerically on a model proton- coupled electron transfer in different non-adiabatic regimes.

  9. Limiting factors for development of ambulatory breast surgery in the French hospital network.

    Science.gov (United States)

    Dravet, F; Peuvrel, P; Robard, S; Labbe, D; Michy, T; François, T; Théard, J-L; Classe, J-M

    2011-04-01

    Ambulatory breast surgery is not well developed in France. This is especially true for oncologic procedures, Between January 2005 and June 2006, we performed a retrospective evaluation of the factors thought to limit the development of this type of hospitalization. The principal limiting factors were distance restrictions (respect of the 100 km perimeter), the complexity of patient management for small breast tumors (several practitioners involved) and last, the non-motivating reimbursement policy. By changing to the Anglo-American ("one day surgery", i.e. hospital stay less than 24 hours) or hybrid system (less than 12 hours+1 day surgery), ambulatory surgery could easily be offered to patients excluded by the current system (ambulatory department open less than 12 hours). Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  10. Impact of selected risk factors on expected lifetime without long-standing, limiting illness in Denmark

    DEFF Research Database (Denmark)

    Brønnum-Hansen, Henrik; Juel, Knud; Davidsen, Michael

    2007-01-01

    OBJECTIVE: To estimate the impacts of tobacco smoking, high alcohol consumption, physical inactivity and overweight on expected lifetime with and without long-standing, limiting illness. METHODS: Life tables for each level of exposure to the risk factors were constructed, mainly on the basis......-olds was 9-10 years shorter for heavy smokers than for those who never smoke, and all the lifetime lost would have been without long-standing, limiting illness. Similarly, all 5 years of expected lifetime lost by men with high alcohol consumption would have been without illness. The expected lifetime without...... long-standing, limiting illness was 8-10 years shorter among sedentary than physically active people. Obesity shortened lifetime without illness by 5 years for men and ten years for women. CONCLUSION: The results of this study could be used in health policy-making, as the potential gains in public...

  11. Evidence from neuroimaging to explore brain plasticity in humans during an ultra-endurance burden

    Directory of Open Access Journals (Sweden)

    Perrey Stéphane

    2012-12-01

    Full Text Available Abstract Physical activity, likely through induction of neuroplasticity, is a promising intervention to promote brain health. In athletes it is clear that training can and does, by physiological adaptations, extend the frontiers of performance capacity. The limits of our endurance capacity lie deeply in the human brain, determined by various personal factors yet to be explored. The human brain, with its vast neural connections and its potential for seemingly endless behaviors, constitutes one of the final frontiers of medicine. In a recent study published in BMC Medicine, the TransEurope FootRace Project followed 10 ultra-endurance runners over around 4,500 km across Europe and recorded a large data collection of brain imaging scans. This study indicates that the cerebral atrophy amounting to a reduction of approximately 6% throughout the two months of the race is reversed upon follow-up. While this study will contribute to advances in the limits of human performance on the neurophysiological processes in sports scientists, it will also bring important understanding to clinicians about cerebral atrophy in people who are vulnerable to physical and psychological stress long term. See related research article http://www.biomedcentral.com/1741-7015/10/170

  12. What is the most prominent factor limiting photosynthesis in different layers of a greenhouse cucumber canopy?

    Science.gov (United States)

    Chen, Tsu-Wei; Henke, Michael; de Visser, Pieter H B; Buck-Sorlin, Gerhard; Wiechers, Dirk; Kahlen, Katrin; Stützel, Hartmut

    2014-09-01

    Maximizing photosynthesis at the canopy level is important for enhancing crop yield, and this requires insights into the limiting factors of photosynthesis. Using greenhouse cucumber (Cucumis sativus) as an example, this study provides a novel approach to quantify different components of photosynthetic limitations at the leaf level and to upscale these limitations to different canopy layers and the whole plant. A static virtual three-dimensional canopy structure was constructed using digitized plant data in GroIMP. Light interception of the leaves was simulated by a ray-tracer and used to compute leaf photosynthesis. Different components of photosynthetic limitations, namely stomatal (S(L)), mesophyll (M(L)), biochemical (B(L)) and light (L(L)) limitations, were calculated by a quantitative limitation analysis of photosynthesis under different light regimes. In the virtual cucumber canopy, B(L) and L(L) were the most prominent factors limiting whole-plant photosynthesis. Diffusional limitations (S(L) + M(L)) contributed Photosynthesis in the lower canopy was more limited by the biochemical capacity, and the upper canopy was more sensitive to light than other canopy parts. Although leaves in the upper canopy received more light, their photosynthesis was more light restricted than in the leaves of the lower canopy, especially when the light condition above the canopy was poor. An increase in whole-plant photosynthesis under diffuse light did not result from an improvement of light use efficiency but from an increase in light interception. Diffuse light increased the photosynthesis of leaves that were directly shaded by other leaves in the canopy by up to 55%. Based on the results, maintaining biochemical capacity of the middle-lower canopy and increasing the leaf area of the upper canopy would be promising strategies to improve canopy photosynthesis in a high-wire cucumber cropping system. Further analyses using the approach described in this study can be expected to

  13. Thermodynamic limit of particle-hole form factors in the massless XXZ Heisenberg chain

    Energy Technology Data Exchange (ETDEWEB)

    Kitanine, N. [Univ. de Bourgogne (France). IMB, UMR 5584 du CNRS; Kozlowski, K.K. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Maillet, J.M.; Terras, V. [ENS Lyon (France). UMR 5672 du CNRS, Lab. de Physique; Slavnov, N.A. [Steklov Mathematical Inst., Moscow (Russian Federation)

    2011-03-15

    We study the thermodynamic limit of the particle-hole form factors of the XXZ Heisenberg chain in the massless regime. We show that, in this limit, such form factors decrease as an explicitly computed power-law in the system size. Moreover, the corresponding amplitudes can be obtained as a product of a ''smooth'' and a ''discrete'' part: the former depends continuously on the rapidities of the particles and holes, whereas the latter has an additional explicit dependence on the set of integer numbers that label each excited state in the associated logarithmic Bethe equations. We also show that special form factors corresponding to zero-energy excitations lying on the Fermi surface decrease as a power-law in the system size with the same critical exponents as in the longdistance asymptotic behavior of the related two-point correlation functions. The methods we develop in this article are rather general and can be applied to other massless integrable models associated to the six-vertex R-matrix and having determinant representations for their form factors. (orig.)

  14. Reaching the theoretical resonance quality factor limit in coaxial plasmonic nanoresonators fabricated by helium ion lithography.

    Science.gov (United States)

    Melli, M; Polyakov, A; Gargas, D; Huynh, C; Scipioni, L; Bao, W; Ogletree, D F; Schuck, P J; Cabrini, S; Weber-Bargioni, A

    2013-06-12

    Optical antenna structures have revolutionized the field of nano-optics by confining light to deep subwavelength dimensions for spectroscopy and sensing. In this work, we fabricated coaxial optical antennae with sub-10-nanometer critical dimensions using helium ion lithography (HIL). Wavelength dependent transmission measurements were used to determine the wavelength-dependent optical response. The quality factor of 11 achieved with our HIL fabricated structures matched the theoretically predicted quality factor for the idealized flawless gold resonators calculated by finite-difference time-domain (FDTD). For comparison, coaxial antennae with 30 nm critical dimensions were fabricated using both HIL and the more common Ga focus ion beam lithography (Ga-FIB). The quality factor of the Ga-FIB resonators was 60% of the ideal HIL results for the same design geometry due to limitations in the Ga-FIB fabrication process.

  15. Functional Factor Analysis In Sesame Under Water - Limiting Stress: New Concept On An Old Method

    Directory of Open Access Journals (Sweden)

    Mansouri Sadollah

    2014-12-01

    Full Text Available Multivariate statistical analysis, through their ability to extract hidden relationship between various traits, has a wide application in breeding programs. Having physiological concept on the multivariate analysis, factor analysis was used to extract differential relationships between different components involving in assimilate partitioning in sesame under regular irrigation regime and limited irrigation. The analysis revealed that under regular irrigation regime, the stored and/or currently produced assimilates are allocated to the filling seeds. However, incidence of water shortage in the beginning of flowering time make shifts in assimilate partitioning from formation of new seeds or capsules to the not-matured pre-formed seeds, which results in seeds with more nutrient storage. This indicates the requirement for change in breeding strategies under sub-optimal condition. The possible common language between factor concept in multivariate analysis, QTLs in genetics, and transcription factors in molecular biology is indicated.

  16. Comparing the demographic factors of patient with limited and diffuse type of alopecia areata

    Directory of Open Access Journals (Sweden)

    Mina Daliri

    2010-09-01

    Full Text Available Background: Alopecia areata is a chronic inflammatory disease that involves the hair follicle. Clinically, patients with alopecia areata may have patchy or confluent hair loss on the scalp or body so we conduct a study to compare the demographic aspects of patient with limited and diffuse type of alopecia areata.Materials and Method: We conducted a descriptive-analyzing study in which 306 patient were chosen. The patients were divided into two groups of diffuse and limited Alopecia. Demographic factors including age, gender, disease onset were compared in two groups. Results: Out of 306 patients, 58.8 % were male and 41.2 % were female. 247 patients (80.7% suffered from limited type and 59 patients (19.2% suffered from diffuse type. The mean age of the onset of involvement in limited group was 21.9±12 yr and 15.8±12 yr in diffuse group. The mean duration of involvement in limited group was 18.7 months and 71 months in diffuse group. Conclusion: Diffuse type alopecia areata starts at lower age and has longer duration. Our study results were similar to the others. Like other studies, thyroid disorders and atopic dermatitis are positively correlative to the severity of disease

  17. Upregulation of circulating IL-15 by treadmill running in healthy individuals: is IL-15 an endocrine mediator of the beneficial effects of endurance exercise?

    Science.gov (United States)

    Tamura, Yoshiaki; Watanabe, Keiichi; Kantani, Tomomi; Hayashi, Junichi; Ishida, Nobuhiko; Kaneki, Masao

    2011-01-01

    The beneficial effects of endurance exercise include insulin-sensitization and reduction of fat mass. Limited knowledge is available about the mechanisms by which endurance exercise exerts the salutary effects. Myokines, cytokines secreted by skeletal muscle, have been recognized as a potential mediator. Recently, a role of skeletal muscle-derived interleukin-15 (IL-15) in improvement of fat-lean body mass composition and insulin sensitivity has been proposed. Yet, previous studies have reported that endurance training does not increase production or secretion of IL-15 in skeletal muscle. Here, we show that in opposition to previous findings, 30-min treadmill running at 70% of age-predicted maximum heart rate resulted in a significant increase in circulating IL-15 level in untrained healthy young men. These findings suggest that IL-15 might play a role in the systemic anti-obesogenic and insulin-sensitizing effects of endurance exercise, not only as a paracrine and autocrine but also as an endocrine factor.

  18. The limits of human athletic performance.

    Science.gov (United States)

    Maughan, R J

    2005-01-01

    For each individual, there is a limit to the capacity to perform exercise. The limitation, however, depends on the nature of the task and is also influenced by a number of other factors. Muscle strength is determined largely by muscle mass, specifically muscle cross-sectional area, but is also influenced by neural drive and biomechanical factors. Endurance performance depends on both cardiovascular capacity and the metabolic characteristics of the skeletal muscles. These factors are determined in part by genetic endowment: the elite sprinter has a high proportion of Type 2 muscle fibres while the leg muscles of the successful marathon runner are composes mainly of Type 1 fibres. Whatever the genetic potential, expression of this depends on the intensity, duration and frequency of the applied training stimulus, diet and other factors. The limitation may also depend on environmental factors, such as altitude and temperature.

  19. Factors Limiting Adoption of Technologies by Farmers in Catabola Municipality, Angola

    Directory of Open Access Journals (Sweden)

    Rušarová K.

    2016-06-01

    Full Text Available The objective of the paper is to define the factors influencing the adoption of animal traction and/or mechanical-power technology in the conditions of Catabola municipality where hand-tool technology is being used on 99.7% of the area cultivated by small farmers. Primary data collection was conducted in the period July–August 2011; semi-structured questionnaires and focus group discussions were the most frequent methods used. In total, 151 small-scale farmers from 9 villages participated in the survey. Ten factors influencing the dependent variable – level of technology used by farmers in combination with hiring of labour – were defined. The factors were statistically analyzed by ANOVA. The area of cultivated land and the educational level of both parents and children were found to be the factors limiting the process of animal traction or mechanical power adoption by small farmers in the Catabola municipality. In addition, a relatively high rate of child labour was observed. With the exclusion of childless families, 62.7% of small farmer families regularly use children aged 0–14 years for field operations. The results confirm that the factor of hiring extra labour is irrelevant in determining the development in technology use by small farmers in the Catabola municipality.

  20. Fruitful factors: what limits seed production of flowering plants in the alpine?

    Science.gov (United States)

    Straka, Jason R; Starzomski, Brian M

    2015-05-01

    Predicting demographic consequences of climate change for plant communities requires understanding which factors influence seed set, and how climate change may alter those factors. To determine the effects of pollen availability, temperature, and pollinators on seed production in the alpine, we combined pollen-manipulation experiments with measurements of variation in temperature, and abundance and diversity of potential pollinators along a 400-m elevation gradient. We did this for seven dominant species of flowering plants in the Coast Range Mountains, British Columbia, Canada. The number of viable seeds set by plants was influenced by pollen limitation (quantity of pollen received), mate limitation (quality of pollen), temperature, abundance of potential pollinators, seed predation, and combinations of these factors. Early flowering species (n = 3) had higher seed set at high elevation and late-flowering species (n = 4) had higher seed set at low elevation. Degree-days >15 °C were good predictors of seed set, particularly in bee-pollinated species, but had inconsistent effects among species. Seed production in one species, Arnica latifolia, was negatively affected by seed-predators (Tephritidae) at mid elevation, where there were fewer frost-hours during the flowering season. Anemone occidentalis, a fly-pollinated, self-compatible species had high seed set at all elevations, likely due to abundant potential pollinators. Simultaneously measuring multiple factors affecting reproductive success of flowering plants helped identify which factors were most important, providing focus for future studies. Our work suggests that responses of plant communities to climate change may be mediated by flowering time, pollination syndrome, and susceptibility to seed predators.

  1. Factors associated with functional limitations in the daily living activities of Japanese hip osteoarthritis patients.

    Science.gov (United States)

    Kondo, Kyoko; Jingushi, Seiya; Ohfuji, Satoko; Sofue, Muroto; Itoman, Moritoshi; Matsumoto, Tadami; Hamada, Yoshiki; Shindo, Hiroyuki; Takatori, Yoshio; Yamada, Harumoto; Yasunaga, Yuji; Ito, Hiroshi; Mori, Satoshi; Owan, Ichiro; Fujii, Genji; Ohashi, Hirotsugu; Fukushima, Wakaba; Maeda, Akiko; Inui, Miki; Takahashi, Shinji; Hirota, Yoshio

    2016-12-10

    As society ages, there is a vast number of elderly people with locomotive syndrome. In this study, the factors associated with functional limitations in daily living activities evaluated by female hip osteoarthritis (OA) patients were investigated. This study was a cross-sectional study. The subjects were 353 female patients who were newly diagnosed with hip OA at an orthopedic clinic with no history of hip joint surgery. Outcome indices were functional limitations in two daily living activities obtained from a questionnaire completed by the patients: (i) standing up (standing from a crouched position) and (ii) stair-climbing (climbing and/or descending stairs). The odds ratios (ORs) and 95% confidence intervals (CIs) were computed for explanatory variables using the proportional odds model in logistic regression to evaluate their associations with functional limitations. Functional limitations in standing up were associated with heavy weight (third tertile vs. first tertile: 1.91, 1.11-3.27), participation in sports at school (0.62, 0.40-0.98), parity (vs. nullipara: 1.96, 1.08-3.56), old age and OA stage. Associations with functional limitations in stair-climbing were seen with short height (weight, parity, shorter height and bilateral OA were associated with functional limitations in standing up and/or stair-climbing, whereas participation in sports such as club activities in school maintained standing up. © 2016 The Authors. International Journal of Rheumatic Diseases published by Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

  2. Power equations in endurance sports.

    Science.gov (United States)

    van Ingen Schenau, G J; Cavanagh, P R

    1990-01-01

    This paper attempts to clarify the formulation of power equations applicable to a variety of endurance activities. An accurate accounting of the relationship between the metabolic power input and the mechanical power output is still elusive, due to such issues as storage and recovery of strain energy and the differing energy costs of concentric and eccentric muscle actions. Nevertheless, an instantaneous approach is presented which is based upon the application of conventional Newtonian mechanics to a rigid segment model of the body, and does not contain assumptions regarding the exact nature of segmental interactions--such as energy transfer, etc. The application of the equation to running, cycling, speed skating, swimming and rowing is discussed and definitions of power, efficiency, and economy are presented.

  3. Limits on the Fill Factor in Organic Photovoltaics: Distinguishing Nongeminate and Geminate Recombination Mechanisms.

    Science.gov (United States)

    Dibb, George F A; Jamieson, Fiona C; Maurano, Andrea; Nelson, Jenny; Durrant, James R

    2013-03-07

    In this Letter, we present transient optoelectronic experimental studies of the recombination processes limiting the fill factor (FF) in three conjugated polymer:fullerene systems, poly(3-hexylthiophene) (P3HT) and two lower-band-gap polymers that exhibit lower FFs poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']dithiophene)-alt-4,7-(2,1,3-benzothiadiazole) (PCPDTBT) and poly(2,7-(9,9-dioctylfluorene)-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)) (APFO-3). Using transient absorption spectroscopy, charge extraction, and transient photovoltage experiments, we show that the lower FF observed for the PCPDTBT-based device results from enhanced nongeminate recombination even at short circuit, In contrast, we show that for APFO-3 devices, the FF is primarily limited by a voltage-dependent free charge generation, which we assign to a geminate recombination process.

  4. Risk factors for treatment-limiting toxicities in patients starting nevirapine-containing antiretroviral therapy

    DEFF Research Database (Denmark)

    Kesselring, Anouk M; Wit, Ferdinand W; Sabin, Caroline A;

    2009-01-01

    BACKGROUND: This collaboration of seven observational clinical cohorts investigated risk factors for treatment-limiting toxicities in both antiretroviral-naive and experienced patients starting nevirapine-based combination antiretroviral therapy (NVPc). METHODS: Patients starting NVPc after 1...... to treatment-limiting toxicities and/or patient/physician choice (TOXPC, n = 10,186). Patients were classified according to prior antiretroviral treatment experience and CD4 cell count/viral load at start NVPc. Models were stratified by cohort and adjusted for age, sex, nadir CD4 cell count, calendar year...... of starting NVPc and mode of transmission. RESULTS: Median time from starting NVPc to TOXPC and HSR were 162 days [interquartile range (IQR) 31-737] and 30 days (IQR 17-60), respectively. In adjusted Cox analyses, compared to naive patients with a low CD4 cell count, treatment-experienced patients with high...

  5. Cooling During Exercise: An Overlooked Strategy for Enhancing Endurance Performance in the Heat.

    Science.gov (United States)

    Stevens, Christopher J; Taylor, Lee; Dascombe, Ben J

    2017-05-01

    It is well established that endurance performance is negatively affected by environmental heat stress due to a complex interaction of physical, physiological and psychological alterations. Numerous scientific investigations have attempted to improve performance in the heat with pre-cooling (cooling prior to an exercise test), and as such this has become a well-established ergogenic practice for endurance athletes. However, the use of mid-cooling (cooling during an exercise test) has received considerably less research attention in comparison, despite recent evidence to suggest that the advantage gained from mid-cooling may outweigh that of pre-cooling. A range of mid-cooling strategies are beneficial for endurance performance in the heat, including the ingestion of cold fluids and ice slurry, both with and without menthol, as well as cooling of the neck and face region via a cooling collar or water poured on the head and face. The combination of pre-cooling and mid-cooling has also been effective, but few comparisons exist between the timing and type of such interventions. Therefore, athletes should experiment with a range of suitable mid-cooling strategies for their event during mock competition scenarios, with the aim to determine their individual tolerable limits and performance benefits. Based on current evidence, the effect of mid-cooling on core temperature appears largely irrelevant to any subsequent performance improvements, while cardiovascular, skin temperature, central nervous system function and psychophysiological factors are likely involved. Research is lacking on elite athletes, and as such it is currently unclear how this population may benefit from mid-cooling.

  6. Hannelore Wass: Death Education--An Enduring Legacy.

    Science.gov (United States)

    Doka, Kenneth J

    2015-01-01

    Hannelore Wass's enduring contribution to the field of thanatology focused on death education In addition to developing a journal initially focused on that topic, Wass also created one of the first text books in the field. This article explores the factors that caused death education to emerge in the late 1960s as well as issues that death education still faces as it continues to evolve.

  7. Energy Availability and Reproductive Function in Female Endurance Athletes

    DEFF Research Database (Denmark)

    Melin, Anna Katarina

    The overall aim of this PhD project was to study the prevalence and potential dietary risk factors and consequences of current low EA and oligomenorrhea/functionel hypothalamic amenorrhea (FHA) in a group of female elite endurance athletes. The results indicated that athletes with current low and......-reported screening tool to complement existing validated disordered eating screening instruments for the identification of female athletes at risk for the Triad....

  8. Factors Limiting Centralized Land Circulation in China from the Perspective of Farmers’ Property Right

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    At present,there are many factors limiting large area centralized,rapid development,and moderately large-scale land operation in China.These factors include(i) the existing land utilization system is still at adaptation stage,and it lacks universal agreement of people on large-scale land operation;(ii) farmers’ dependence on land is great;(iii) it is difficult to transfer surplus labor;(iv) there is no positive connection between promotion of moderately large-scale land operation and realization of increase of farmers’ income;(v) it remains to be proved whether large-scale operation can become a stable rural occupation and whether big farming households can grow to professional farmers;(vi) large-scale land operation in rural areas may lead to waste of resources;(vii) the promotion of large-scale land operation may cause other social contradictions.

  9. ESTIMATING VITICULTURAL FAVORABILITY OF COTNARI VINEYARD AREA AND IDENTIFYING LIMITING FACTORS

    Directory of Open Access Journals (Sweden)

    Cristina Chiriac

    2012-12-01

    Full Text Available For estimating the favorability of agricultural lands for vine in Cotnari vineyard area, we used 16 indicators provided in the Methodology of Soil Survey (Second part and third part - 1986. To determine the average coefficient of evaluation, respectively the class of favorability for the vine in Cotnari Vineyard, we calculated the notes of evaluation for 10 administrative units from Cotnari Vineyard: Flămânzi, Frumuşica, Deleni, Hârlău, Scobinţi, Cepleniţa, Cotnari, Cucuteni, Todireşti, Târgu Frumos. For each administrative unit were selected the territorial units of soil (U.S. within Cotnari Vineyard, from which we extracted only the ecological homogeneous territories (TEO's that are planted with vine. Among the limiting factors identified in Cotnari Vineyard we mention the geomorphologic factor (slope, landslides, the pedological factor (gleying, stagnogleying,salinization/alkalization, texture, reaction, humus content, edaphic volume and the hydrological factor (groundwater depth, excess moisture in surface, flooding by overflow.

  10. Genome-wide association study identifies three novel genetic markers associated with elite endurance performance

    DEFF Research Database (Denmark)

    Ahmetov, Ii; Kulemin, Na; Popov, Dv

    2015-01-01

    in elite endurance athletes (95.5%) in comparison with non-elite endurance athletes (89.8%, P = 0.0257), Russian (88.8%, P = 0.007) and European (90.6%, P = 0.0197) controls and power athletes (86.2%, P = 0.0005). The rs1572312 SNP is located on the nuclear factor I A antisense RNA 2 (NFIA-AS2) gene which...

  11. Endurance test on IR rig for RI production

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Heung June; Youn, Y. J.; Han, H. S.; Hong, S. B.; Cho, Y. G.; Ryu, J. S

    2000-12-01

    This report presents the pressure drop, vibration and endurance test results for IR rig for RI production which were desigened and fabricated by KAERI. From the pressure drop test results, it is noted that the flow rate through the IR rig corresponding to the pressure drop of 200 kPa is measured to be about 3.12 kg/sec. Vibration frequency for the IR rig ranges from 13 to 17 Hz. RMS(Root Mean Square) displacement for the IR rig is less than 30 {mu}m, and the maximum displacement is less than 110{mu}m. These experimental results show that the design criteria of IR rig meet the HANARO limit conditions. Endurance test results show that the appreciable fretting wear for the IR rig does not occur, however tiny trace of wear between contact points is observed.

  12. Factors limiting deceased organ donation: focus groups' perspective from culturally diverse community.

    Science.gov (United States)

    Wong, L P

    2010-06-01

    In-depth understanding of cultural and religious factors limiting organ donation of three ethnic populations (Malay, Chinese, and Indian) in Southeast Asia is lacking. Identification of factors limiting organ donation among these three ethnic groups will provide insights into culturally appropriate strategies to promote acceptance of organ donation in a multiethnic Asian community. A total of 17 focus group discussions (105 participants) were conducted between September and December 2008. Participants were members of the general public aged 18 to 60 years, recruited through convenient sampling around the Klang Valley area of Malaysia. Although the majority had favorable attitudes toward deceased organ donation and transplantation, a diversity of myths and misinformation were unearthed from the discussions across the ethnic groups. These include perceived religious prohibition, cultural myths and misperceptions, fear of disfigurement, fear of surgery, distrust of the medical system, and family disapproval. Culture and religious beliefs played important prohibitive roles among those opposed to organ donations. There were distinctive ethnic differences in cultural and religious concerns regarding organ donation. Less-educated and rural groups appeared to have more misconceptions than the well-educated and the urban groups. Our findings may assist organ donation and transplantation organizations to reach diverse sociodemographic and ethnic communities with culture-specific information about organ donation. The involvement of community and religious leaders is critical in organ donation requests.

  13. The natural conditions as a limiting factor for the development of Serbian-Macedonian border area

    Directory of Open Access Journals (Sweden)

    Dragićević Slavoljub

    2010-01-01

    Full Text Available Natural conditions of certain area imply to the complex influence of various elements of the environment (surface, relief, climate, water, vegetation type and man, and knowledge of their recent state represents basis of an integrated approach in the land use planning. Analysis of natural conditions and processes in the Serbian-Macedonian border area is usually done through the valorization of natural potentials, but aspect of their limiting influence on the development of this territory - natural hazards assessment has remained unresolved. Degree of natural hazards vulnerability of a certain territory is an important factor in land use planning, because it represents a threat to the undisturbed development of a certain teritory. The basic idea of this paper is to provide multi-hazard assessment and the integral map of areas vulnerable to various types of natural hazards in Serbian-Macedonian border area. In this way seclusion of areas where natural conditions can represent the limiting factor for the development of the analyzed territory shall be performed.

  14. Limiting factors for nomadic pastoralism in Mongolian steppe: A hydrologic perspective

    Science.gov (United States)

    Sugita, Michiaki; Yoshizawa, Shintaroh; Byambakhuu, Ishgaldan

    2015-05-01

    In this study, limiting factors for continuing nomadic pastoralism in steppe areas were studied based on a hydrologic perspective. Two small watersheds in central Mongolia were selected for an assessment of water balance and hydrologic processes. We determined that the majority of annual precipitation, ∼88-96 mm, was lost by evaporation (82%) while only a small proportion went to groundwater discharge, surface runoff, and groundwater consumption by nomadic activities. The soil column was found to absorb large fluctuations in precipitation although its connection to groundwater was very weak. Groundwater recharge was, therefore, very small and occurred only rarely during heavy rainfall events in valley bottoms. However, current water storage in shallow groundwater was determined to be quite sufficient for continuing nomadic pastoralism when compared to the drinking water requirements of livestock. The main limiting factors identified were a temporal lack of feed to animals due to a loss of aboveground biomass resulting from soil moisture shortages during drought conditions, and a decline in the number and maintenance level of the traditional well network that, due to access to shallow groundwater, has allowed herders to migrate to areas with better conditions in remote Mongolian steppe.

  15. Investigating Limiting Factors in Stretchable All-Carbon Transistors for Reliable Stretchable Electronics.

    Science.gov (United States)

    Chortos, Alex; Zhu, Chenxin; Oh, Jin Young; Yan, Xuzhou; Pochorovski, Igor; To, John W-F; Liu, Nan; Kraft, Ulrike; Murmann, Boris; Bao, Zhenan

    2017-08-22

    Stretchable form factors enable electronic devices to conform to irregular 3D structures, including soft and moving entities. Intrinsically stretchable devices have potential advantages of high surface coverage of active devices, improved durability, and reduced processing costs. This work describes intrinsically stretchable transistors composed of single-walled carbon nanotube (SWNT) electrodes and semiconductors and a dielectric that consists of a nonpolar elastomer. The use of a nonpolar elastomer dielectric enabled hysteresis-free device characteristics. Compared to devices on SiO2 dielectrics, stretchable devices with nonpolar dielectrics showed lower mobility in ambient conditions because of the absence of doping from water. The effect of a SWNT band gap on device characteristics was investigated by using different SWNT sources as the semiconductor. Large-band-gap SWNTs exhibited trap-limited behavior caused by the low capacitance of the dielectric. In contrast, high-current devices based on SWNTs with smaller band gaps were more limited by contact resistance. Of the tested SWNT sources, SWNTs with a maximum diameter of 1.5 nm performed the best, with a mobility of 15.4 cm(2)/Vs and an on/off ratio >10(3) for stretchable transistors. Large-band-gap devices showed increased sensitivity to strain because of a pronounced dependence on the dielectric thickness, whereas contact-limited devices showed substantially less strain dependence.

  16. Rate limiting factors in trichloroethylene co-metabolic degradation by phenol-grown aerobic granules.

    Science.gov (United States)

    Zhang, Yi; Tay, Joo Hwa

    2014-04-01

    The potential of aerobic granular sludge in co-metabolic removal of recalcitrant substances was evaluated using trichloroethylene (TCE) as the model compound. Aerobic granules cultivated in a sequencing batch reactor with phenol as the growth substrate exhibited TCE and phenol degradation activities lower than previously reported values. Depletion of reducing energy and diffusion limitation within the granules were investigated as the possible rate limiting factors. Sodium formate and citrate were supplied to the granules in batch studies as external electron sources. No significant enhancing effect was observed on the instant TCE transformation rates, but 10 mM formate could improve the ultimate transformation capacity by 26 %. Possible diffusion barrier was studied by sieving the biomass into five size fractions, and determining their specific TCE and phenol degradation rates and capacities. Biomass in the larger size fractions generally showed lower activities. Large granules of >700 μm diameter exhibited only 22 % of the flocs' TCE transformation capacity and 35 % of its phenol dependent SOUR, indicating the possible occurrence of diffusion limitation in larger biomass. However, the highest specific TCE transformation rate was observed with the fraction that mostly consisted of small granules (150-300 μm), suggesting an optimal size range while applying aerobic granules in TCE co-metabolic removal.

  17. Food as a limiting factor for Aedes aegypti in water-storage containers.

    Science.gov (United States)

    Arrivillaga, Jazzmin; Barrera, Roberto

    2004-06-01

    An understanding of the ecological factors that regulate natural populations of Aedes aegypti mosquitoes can improve control and reduce the incidence of dengue (DF) and dengue hemorrhagic fever (DHF) in tropical areas. We investigated whether immature Ae. aegypti in water-storage containers from an urban area were under food limitation. We used starvation resistance (number of days alive without food) as an indicator of the feeding history in third-instar Ae. aegypti larvae. Resistance to starvation and other measures of immature success, such as development time, survival, and adult mass, were investigated across a wide range of feeding conditions in the laboratory. Resistance to starvation of third-instar larvae and body mass of adults emerging from pupae collected in water-storage containers in an urban area were compared with the laboratory results. If resistance to starvation and adult mass of field-collected Ae. aegypti corresponded with the lower levels of feeding in the laboratory, then food limitation could be inferred in field-collected larvae. Results showed that resistance to starvation was well correlated with previous feeding levels and with the other measures of immature success. Both resistance to starvation and adult body mass of field-collected specimens corresponded with the lower levels of feeding in the laboratory. Therefore, it was concluded that food limitation or competition is likely to be a regulatory factor in water-storage containers in the urban area. It is recommended that any control measure applied to immature Ae. aegypti in water-storage containers should eliminate all or most of the individuals, otherwise unintended, undesirable results might occur, such as the production of more and larger adults.

  18. Trait mindfulness as a limiting factor for residual depressive symptoms: an explorative study using quantile regression.

    Directory of Open Access Journals (Sweden)

    Sholto Radford

    Full Text Available Mindfulness has been suggested to be an important protective factor for emotional health. However, this effect might vary with regard to context. This study applied a novel statistical approach, quantile regression, in order to investigate the relation between trait mindfulness and residual depressive symptoms in individuals with a history of recurrent depression, while taking into account symptom severity and number of episodes as contextual factors. Rather than fitting to a single indicator of central tendency, quantile regression allows exploration of relations across the entire range of the response variable. Analysis of self-report data from 274 participants with a history of three or more previous episodes of depression showed that relatively higher levels of mindfulness were associated with relatively lower levels of residual depressive symptoms. This relationship was most pronounced near the upper end of the response distribution and moderated by the number of previous episodes of depression at the higher quantiles. The findings suggest that with lower levels of mindfulness, residual symptoms are less constrained and more likely to be influenced by other factors. Further, the limiting effect of mindfulness on residual symptoms is most salient in those with higher numbers of episodes.

  19. Trait Mindfulness as a Limiting Factor for Residual Depressive Symptoms: An Explorative Study Using Quantile Regression

    Science.gov (United States)

    Radford, Sholto; Eames, Catrin; Brennan, Kate; Lambert, Gwladys; Crane, Catherine; Williams, J. Mark G.; Duggan, Danielle S.; Barnhofer, Thorsten

    2014-01-01

    Mindfulness has been suggested to be an important protective factor for emotional health. However, this effect might vary with regard to context. This study applied a novel statistical approach, quantile regression, in order to investigate the relation between trait mindfulness and residual depressive symptoms in individuals with a history of recurrent depression, while taking into account symptom severity and number of episodes as contextual factors. Rather than fitting to a single indicator of central tendency, quantile regression allows exploration of relations across the entire range of the response variable. Analysis of self-report data from 274 participants with a history of three or more previous episodes of depression showed that relatively higher levels of mindfulness were associated with relatively lower levels of residual depressive symptoms. This relationship was most pronounced near the upper end of the response distribution and moderated by the number of previous episodes of depression at the higher quantiles. The findings suggest that with lower levels of mindfulness, residual symptoms are less constrained and more likely to be influenced by other factors. Further, the limiting effect of mindfulness on residual symptoms is most salient in those with higher numbers of episodes. PMID:24988072

  20. Iodine distribution in the environment as a limiting factor for roe deer antler development.

    Science.gov (United States)

    Lehoczki, Róbert; Erdélyi, Károly; Sonkoly, Krisztina; Szemethy, László; Csányi, Sándor

    2011-02-01

    The iodine-containing hormones produced by the thyroid gland play a role in the complex neuro-hormonal regulation of antler development. The proper function of the thyroid depends on the adequate iodine supply of the organism, which is directly related to the iodine content of food and drinking water. The purpose of this study was to explore the connection between the iodine content of the water base, which has a strong correlation with the iodine concentration of environmental components available to animals, and the antler weight of roe deer (Capreolus capreolus) shot in Hungarian hunting areas. Using a general linear model, controlling for the collective effects of other environmental factors (deer population density, harvest rate, land use, and soil fertility information), the iodine content of the water base explained 51.4% of the total variance of antler weights. The results suggest that antler weights increase with increasing iodine concentration regardless of other factors; thus, the environmental iodine distribution can be a limiting factor suppressing roe deer performance assessed here as antler weight. Further experimental studies of controlled iodine uptake are needed to define the exact physiological iodine requirements of roe deer bucks.

  1. Endurance training enhances BDNF release from the human brain

    DEFF Research Database (Denmark)

    Seifert, Thomas; Brassard, Patrice; Wissenberg, Mads

    2010-01-01

    the human brain as detected from arterial and internal jugular venous blood samples. In a randomized controlled study, 12 healthy sedentary males carried out 3 mo of endurance training (n = 7) or served as controls (n = 5). Before and after the intervention, blood samples were obtained at rest and during...... in the hippocampus (4.5 + or - 1.6 vs. 1.4 + or - 1.1 mRNA/ssDNA; P human brain following training suggest......The circulating level of brain-derived neurotrophic factor (BDNF) is reduced in patients with major depression and type-2 diabetes. Because acute exercise increases BDNF production in the hippocampus and cerebral cortex, we hypothesized that endurance training would enhance the release of BDNF from...

  2. Survival of the Fittest: Why Terrorist Groups Endure

    Directory of Open Access Journals (Sweden)

    Joseph K. Young

    2014-04-01

    Full Text Available Why do terrorist groups endure? This question is relevant to scholars and policy makers alike. In the past, this issue was not been addressed in a systematic fashion. Recent work investigates this question using data on transnational groups and finds that factors associated with the home country can influence the duration the group endures. Applying the theory of outbidding to terrorist group survival, we argue that strategic competition among groups predicts group duration. Using the Global Terrorism Database, we develop a dataset using the terrorist group as the unit of analysis to model the duration of group activity and thus include the largest sample of groups yet. Controlling for previous explanations of both group duration and terrorism, we find a robust effect for the impact that group competition has on terrorist group survival.

  3. Risk factors for mortality during antiretroviral therapy in older populations in resource-limited settings

    Directory of Open Access Journals (Sweden)

    Daniel O’Brien

    2016-01-01

    Full Text Available Introduction: An increasing proportion of adult patients initiating antiretroviral therapy (ART in resource-limited settings are aged >50 years. Older populations on ART appear to have heightened risk of death, but little is known about factors influencing mortality in this population. Methods: We performed a retrospective observational multisite cohort study including all adult patients (≥15 years initiating ART between 2003 and 2013 in programmes supported by Médecins Sans Frontières across 12 countries in Asia, Africa and Europe. Patients were stratified into two age groups, >50 years and 15 to 50 years. A Cox proportional hazards model was used to explore factors associated with mortality. Results: The study included 41,088 patients: 2591 (6.3% were aged >50 years and 38,497 (93.7% were aged 15 to 50 years. The mortality rate was significantly higher in the age group >50 years [367 (14.2% deaths; mortality rate 7.67 deaths per 100 person-years (95% confidence interval, CI: 6.93 to 8.50] compared to the age group 15 to 50 years [3788 (9.8% deaths; mortality rate 4.18 deaths per 100 person-years (95% CI: 4.05 to 4.31], p50 age group. WHO Stage 4 conditions were more strongly associated with increased mortality rates in the 15 to 50 age group compared to populations >50 years. WHO Stage 3 conditions were associated with an increased mortality rate in the 15 to 50 age group but not in the >50 age group. Programme region did not affect mortality rates in the >50 age group; however being in an Asian programme was associated with a 36% reduced mortality rate in populations aged 15 to 50 years compared to being in an African programme. There was a higher overall incidence of Stage 3 WHO conditions in people >50 years (12.8/100 person-years compared to those 15 to 50 years (8.1/100 person-years (p50 age groups. Conclusions: Older patients on ART in resource-limited settings have increased mortality rates, but compared to younger populations this

  4. Long endurance underwater power system

    Science.gov (United States)

    1989-01-01

    The development and design of deep sea power sources for long endurances (more than 1 year) and moderate power (more than 1 KW) are unique. The best primary battery (Li-thionyl chloride) would involve huge space and weight and the cost of such a system would be prohibitive. Fuel cells with stored gases need a pressure vessel and also quite a large volume and weight. Aquanautics is engaged in developing a power source to a very demanding design. The design would involve a completely open system eliminating the need for a pressure vessel. Aquanautics will capture oxygen from the seawater to be delivered to a fuel cell. The hydrogen generated in this design is envisioned to be from a reaction between aluminum and seawater. Such a completely open system is already available from Alupower, Inc. This provides for a much safer and more compact design than cryogenic hydrogen. Lithium or magnesium can also be used. Both are expensive and lithium is known to be potentially hazardous. Since the last report, there has been major improvement of the technological issue of carrier longevity. The previous carrier had an operational life of 3 days. At present, Aquanautics has discovered a carrier called 23SuzyP which has stable electrochemical performance for over a month.

  5. Growth hormone enhances effects of endurance training on oxidative muscle metabolism in elderly women

    DEFF Research Database (Denmark)

    Lange, K H; Isaksson, F; Juul, A

    2000-01-01

    The present study investigated whether recombinant human (rh) growth hormone (GH) combined with endurance training would have a larger effect on oxidative capacity, metabolism, and body fat than endurance training alone. Sixteen healthy, elderly women, aged 75 yr, performed closely monitored...... endurance training on a cycle ergometer over 12 wk. rhGH was given in a randomized, double-blinded, placebo-controlled design in addition to the training program. GH administration resulted in a doubling of serum insulin-like growth factor I levels. With endurance training, peak oxygen uptake increased...... by approximately 18% in both groups, whereas the marked increase in muscle citrate synthase activity was 50% larger in the GH group compared with the placebo group. In addition, only the GH group revealed an increase in muscle L-3-hydroxyacyl-CoA dehydrogenase activity. Body weight remained unchanged in both...

  6. Long Endurance Flight Schemes for UAVs Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A system for autonomous detection and exploitation of weather phenomena for endurance or range enhancement for loitering unmanned air vehicles is presented. The...

  7. Long Endurance Flight Schemes for UAVs Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A method for providing endurance enhancement for unmanned aerial vehicles based on atmospheric phenomena is presented. The proposed method allows the UAV to sense...

  8. Study of speed endurance middle distance runners

    Directory of Open Access Journals (Sweden)

    Golovaschenko R.V.

    2013-12-01

    Full Text Available Purpose : To investigate the boost performance speed endurance runners who specialize in middle-distance running . Material and methods : The study involved team members Vinnytsia region in an amount of 44 people, whose average age was 20,2 ± 2,1 years. Classes are held during the 21-day mesocycle, 5 times a week, twice a day. Things were aimed at enhancing the development of indicators of special speed endurance. Results : The dynamics of the running speed of the model segments that characterize speed endurance athletes. Proved that the improved running 400 meter intervals helps reduce travel time competitive distance of 1500 meters. Conclusion : The use of the program contributes to higher speed endurance, which determines the result in the women's 1,500 meters.

  9. The search for life on Europa: limiting environmental factors, potential habitats, and Earth analogues.

    Science.gov (United States)

    Marion, Giles M; Fritsen, Christian H; Eicken, Hajo; Payne, Meredith C

    2003-01-01

    The putative ocean of Europa has focused considerable attention on the potential habitats for life on Europa. By generally clement Earth standards, these Europan habitats are likely to be extreme environments. The objectives of this paper were to examine: (1) the limits for biological activity on Earth with respect to temperature, salinity, acidity, desiccation, radiation, pressure, and time; (2) potential habitats for life on Europa; and (3) Earth analogues and their limitations for Europa. Based on empirical evidence, the limits for biological activity on Earth are: (1) the temperature range is from 253 to 394 K; (2) the salinity range is a(H2O) = 0.6-1.0; (3) the desiccation range is from 60% to 100% relative humidity; (4) the acidity range is from pH 0 to 13; (5) microbes such as Deinococcus are roughly 4,000 times more resistant to ionizing radiation than humans; (6) the range for hydrostatic pressure is from 0 to 1,100 bars; and (7) the maximum time for organisms to survive in the dormant state may be as long as 250 million years. The potential habitats for life on Europa are the ice layer, the brine ocean, and the seafloor environment. The dual stresses of lethal radiation and low temperatures on or near the icy surface of Europa preclude the possibility of biological activity anywhere near the surface. Only at the base of the ice layer could one expect to find the suitable temperatures and liquid water that are necessary for life. An ice layer turnover time of 10 million years is probably rapid enough for preserving in the surface ice layers dormant life forms originating from the ocean. Model simulations demonstrate that hypothetical oceans could exist on Europa that are too cold for biological activity (T salinities are high, which would restrict life to extreme halophiles. An acidic ocean (if present) could also potentially limit life. Pressure, per se, is unlikely to directly limit life on Europa. But indirectly, pressure plays an important role in

  10. Endurance exercise diverts the balance between Th17 cells and regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Chava Perry

    Full Text Available Endurance, marathon-type exertion is known to induce adverse changes in the immune system. Increased airway hyper-responsiveness and airway inflammation are well documented in endurance athletes and endurance exercise is considered a major risk factor for asthma in elite athletes. Yet, the mechanisms underlying this phenomenon are still to be deduced. We studied the effect of strenuous endurance exercise (marathon and half-ironman triathlon on CD4+ lymphocyte sub-populations and on the balance between effector and regulatory CD4+ lymphocytes in the peripheral blood of trained athletes, Endurance exercise induced a significant increase in Th17 cells and a sustained decrease in peripheral blood regulatory T cells (Tregs. While interleukin (IL-2 levels remained undetectable, post-race serum IL-6 and transforming growth factor (TGF β levels were significantly elevated. Treg levels in sedentary controls' decreased in vitro after incubation with athletes' post-exercise serum, an effect that was attenuated by supplements of IL-2 or anti IL-6 neutralizing antibodies. Our data suggest that exercise-induced changes in serum cytokine levels promote alterations in Tregs and Th17 cell populations, which may divert the subtle balance in the immune system towards inflammation. This may explain allergic and autoimmune phenomena previously reported in endurance athletes and contribute to our understanding of exercise-related asthma.

  11. Factors Limiting Formation of Community Forestry Enterprises in the Southern Mixteca Region of Oaxaca, Mexico

    Science.gov (United States)

    Hernández-Aguilar, José Antonio; Cortina-Villar, Héctor Sergio; García-Barrios, Luis Enrique; Castillo-Santiago, Miguel Ángel

    2017-03-01

    Many studies have considered community-based forestry enterprises to be the best option for development of rural Mexican communities with forests. While some of Mexico's rural communities with forests receive significant economic and social benefits from having a community forestry enterprise, the majority have not formed such enterprises. The purpose of this article is to identify and describe factors limiting the formation of community forestry enterprise in rural communities with temperate forests in the Southern Mixteca region of Oaxaca, Mexico. The study involved fieldwork, surveys applied to Community Board members, and maps developed from satellite images in order to calculate the forested surface area. It was found that the majority of Southern Mixteca communities lack the natural and social conditions necessary for developing community forestry enterprise; in this region, commercial forestry is limited due to insufficient precipitation, scarcity of land or timber species, community members' wariness of commercial timber extraction projects, ineffective local governance, lack of capital, and certain cultural beliefs. Only three of the 25 communities surveyed have a community forestry enterprise; however, several communities have developed other ways of profiting from their forests, including pine resin extraction, payment for environmental services (PES), sale of spring water, and ecotourism. We conclude that community forestry enterprise are not the only option for rural communities to generate income from their forests; in recent years a variety of forest-related economic opportunities have arisen which are less demanding of communities' physical and social resources.

  12. Searching out the hydrogen absorption/desorption limiting reaction factors: Strategies allowing to increase kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Zeaiter, Ali, E-mail: ali.zeaiter@femto-st.fr; Chapelle, David; Nardin, Philippe

    2015-10-05

    Highlights: • A macro scale thermodynamic model that simulates the response of a FeTi-X hydride tank is performed, and validated experimentally. • A sensibility study to identify the most influent input variables that can changes very largely the reaction rate. - Abstract: Hydrogen gas has become one of the most promising energy carriers. Main breakthrough concerns hydrogen solid storage, specially based on intermetallic material use. Regarding the raw material abundance and cost, the AB type alloy FeTi is an auspicious candidate to store hydrogen. Its absorption/desorption kinetics is a basic hindrance to common use, compared with more usual hydrides. First, discussions based on literature help us identifying the successive steps leading to metal hydriding, and allow to introduce the physical parameters which drive or limit the reaction. This analysis leads us to suggest strategies in order to increase absorption/desorption kinetics. Attention is then paid to a thermofluidodynamic model, allowing to describe a macroscopic solid storage reactor. Thus, we can achieve a simulation which describes the overall reaction inside the hydrogen reactor and, by varying the sub-mentioned parameters (thermal conductivity, the powder granularity, environment heat exchange…), we attempt to hierarchy the reaction limiting factors. These simulations are correlated to absorption/desorption experiments for which pressure, temperature and hydrogen flow are recorded.

  13. EFFECTIVENESS OF LAND BASED ENDURANCE TRAINING VERSUS AQUATIC BASED ENDURANCE TRAINING ON IMPROVING ENDURANCE IN NORMAL INDIVIDUALS

    Directory of Open Access Journals (Sweden)

    Sabitha Eunice Regima

    2015-06-01

    Full Text Available Background: Recently the exercises and fitness professionals have adopted water as an alternative medium for delivering programs to improve fitness and health. When exercise on dry land our skeletal muscular, cardiovascular, respiratory and other body systems are greatly affected by the forces of gravity. When exercise in water, the effects created by the gravitational pull on the body are attenuated. Therefore the aim of this study was to determine the effectiveness of land based endurance training and aquatic based endurance training for enhancing endurance in normal individuals. Methods: An experimental study design with 30 subjects healthy individuals between 20-30 years of both sexes currently were divided equally into 2 groups. Group A underwent land based exercises while Group B underwent aquatic based exercises. The outcome measures consist of RPP (rate pressure product, REC HR (recovery heart rate, RHR (resting heart rate and 6MWD (6 minute walking distance was measured before (pre-training and after four weeks of endurance training. Results: In this study, the mean improvement between the 2 groups of land and aquatic based endurance exercises were tested for significance using a dependent t test. The calculated t value were 43.550, 4.583, 16, 5.870 for RPP, REC HR, RHR, 6MWD for group A respectively. For group B 25.922, 12.762, 27.495,19.236 for RPP, REC HR, RHR, 6MWD for group A respectively with p<0.05. This clearly indicated that both land based exercises and aquatic based exercises will improve cardiovascular endurance significantly and there is no significant difference between land based exercises and aquatic based exercises for enhancing endurance in normal individuals. Conclusion: It is concluded that both land based and aquatic based endurance exercises methods produce equivalent, if not same effect on the enhancement of aerobic endurance. There was no significant difference between these two exercising mediums. Nonetheless

  14. Genome-wide association study identifies three novel genetic markers associated with elite endurance performance

    Science.gov (United States)

    Kulemin, NA; Popov, DV; Naumov, VA; Akimov, EB; Bravy, YR; Egorova, ES; Galeeva, AA; Generozov, EV; Kostryukova, ES; Larin, AK; Mustafina, LJ; Ospanova, EA; Pavlenko, AV; Starnes, LM; Żmijewski, P; Alexeev, DG; Vinogradova, OL; Govorun, VM

    2014-01-01

    To investigate the association between multiple single-nucleotide polymorphisms (SNPs), aerobic performance and elite endurance athlete status in Russians. By using GWAS approach, we examined the association between 1,140,419 SNPs and relative maximal oxygen consumption rate (V.O2max) in 80 international-level Russian endurance athletes (46 males and 34 females). To validate obtained results, we further performed case-control studies by comparing the frequencies of the most significant SNPs (with P < 10−5-10−8) between 218 endurance athletes and opposite cohorts (192 Russian controls, 1367 European controls, and 230 Russian power athletes). Initially, six ‘endurance alleles’ were identified showing discrete associations with V.O2max both in males and females. Next, case-control studies resulted in remaining three SNPs (NFIA-AS2 rs1572312, TSHR rs7144481, RBFOX1 rs7191721) associated with endurance athlete status. The C allele of the most significant SNP, rs1572312, was associated with high values of V.O2max (males: P = 0.0051; females: P = 0.0005). Furthermore, the frequency of the rs1572312 C allele was significantly higher in elite endurance athletes (95.5%) in comparison with non-elite endurance athletes (89.8%, P = 0.0257), Russian (88.8%, P = 0.007) and European (90.6%, P = 0.0197) controls and power athletes (86.2%, P = 0.0005). The rs1572312 SNP is located on the nuclear factor I A antisense RNA 2 (NFIA-AS2) gene which is supposed to regulate the expression of the NFIA gene (encodes transcription factor involved in activation of erythropoiesis and repression of the granulopoiesis). Our data show that the NFIA-AS2 rs1572312, TSHR rs7144481 and RBFOX1 rs7191721 polymorphisms are associated with aerobic performance and elite endurance athlete status. PMID:25729143

  15. Understanding Early Contextual and Parental Risk Factors for the Development of Limited Prosocial Emotions.

    Science.gov (United States)

    Waller, Rebecca; Shaw, Daniel S; Forbes, Erika E; Hyde, Luke W

    2015-08-01

    A growing body of evidence suggests that parenting influences the development of youth callous unemotional (CU) behavior. However, less is known about the effects of parenting or contextual risk factors on 'limited prosocial emotions' (LPE), a recent conceptualization of CU behavior added to the DSM-5. We focused on LPE at ages 10-12 and age 20 among low income, urban males (N = 310), and examined potential developmental precursors, including contextual risk factors assessed during infancy and observed maternal warmth during the toddler period. We found unique direct associations between maternal warmth, maternal aggression, and low empathetic awareness on LPE at ages 10-12, controlling for concurrent self-reported antisocial behavior. Further, there were indirect effects of maternal aggression, low empathetic awareness, and difficult infant temperament assessed in infancy on LPE at ages 10-12 via their influence on maternal warmth at age 2. Finally, there were lasting indirect effects of parental warmth on LPE at age 20, via LPE at ages 10-12. We discuss the implications of these findings for ecological models of antisocial behavior and LPE development, and preventative interventions that target the broader early parenting environment.

  16. Understanding early contextual and parental risk factors for the development of limited prosocial emotions

    Science.gov (United States)

    Waller, Rebecca; Shaw, Daniel S.; Forbes, Erika E.; Hyde, Luke W.

    2014-01-01

    A growing body of evidence suggests that parenting influences the development of youth callous unemotional (CU) behavior. However, less is known about the effects of parenting or contextual risk factors on ‘limited prosocial emotions’ (LPE), a recent conceptualization of CU behavior added to the DSM-5. We focused on LPE at ages 10–12 and age 20 among low income, urban males (N = 310), and examined potential developmental precursors, including contextual risk factors assessed during infancy and observed maternal warmth during the toddler period. We found unique direct associations between maternal warmth, maternal aggression, and low empathetic awareness on LPE at ages 10–12, controlling for concurrent self-reported antisocial behavior. Further, there were indirect effects of maternal aggression, low empathetic awareness, and difficult infant temperament assessed in infancy on LPE at ages 10–12 via their influence on maternal warmth at age 2. Finally, there were lasting indirect effects of parental warmth on LPE at age 20, via LPE at ages 10–12. We discuss the implications of these findings for ecological models of antisocial behavior and LPE development, and preventative interventions that target the broader early parenting environment. PMID:25510355

  17. Soil development as limiting factor for shrub expansion in southwestern Greenland

    Science.gov (United States)

    Caviezel, Chatrina; Hunziker, Matthias; Zoller, Oliver; Wüthrich, Christoph; Kuhn, Nikolaus J.

    2014-05-01

    Southern Greenland currently experiences an increase in summer temperatures and a prolonged growing season (Masson-Delmotte et al. 2012), resulting in an increased shrub cover at the boreal - tundra border ecotone (Normand et al. 2013). These findings suggest the beginning of a greener Greenland in which tundra vegetation is transformed to a boreal woody flora. However, vegetation at borderline ecotones is influenced by further ecologic factors than just temperature. In this study, the ecologic conditions at a selection of sites along an elevation gradient near Igaliku in southern Greenland were examined to identify potential factors limiting the expansion of woody vegetation apart from temperature. The sites differ in elevation, topography, shrub density and soil parent material. The three study sites comprise i) well established birch shrubs growing between 50 and 180 m a.s.l., where the parent material origins from the Julianehab granite (Brooks 2012); ii) extended shrub patches at about 250 m a.s.l., where the parent material consists of Gardar Sandstones and Lavas (Brooks 2012) and iii) restricted shrub patches at an elevation of 250 m a.s.l., where the soil parent material originates from the Gardar intrusions (Brooks 2012). The extent of the shrub areas, topography and soil moisture were mapped, additionally soil samples were analyzed for C-and N-content, texture including coarse fraction and pH and used as soil development indicators. Our results show that the topographic setting regulates the existence or absence of soil while the soil parent material is an important limiting factor for soil moisture. According to these findings, we suggest that a high proportion of areas where temperature increase would allow the increase of shrub cover is not suitable for a woody flora. Brooks, Kent. 2012. "A Tale of Two Intrusions—where Familiar Rock Names No Longer Suffice." Geology Today 28 (1): 13-19. doi:10.1111/j.1365-2451.2012.00815.x. Masson-Delmotte, V., D

  18. Limiting Factors for Agricultural Production and Differentiation of Soil Management in Romania

    Science.gov (United States)

    Ioana Moraru, Paula; Rusu, Teodor; Bogdan, Ileana; Ioan Pop, Adrian; Pop, Horia

    2017-04-01

    Romania's land area is 23,839,100 ha; 0.16% of the world's surface. Worldwide, Romania is ranked #83 for areal extent, and it consitutes 4.81% of the Europe's surface (ranked #12). Romania has 14,856,800 ha of agricultural land which represents 62.3% of the total surface; 0.65 ha per capita. At the national level, 72.5% and 27.5% of soils in Romania can be broadly classed as very poor and good/very good, respectively, based on intrinsic soil characteristics, climate, topography, and ground water. Romania has a specific geographical situation, namely: i) Romanian territory is located in the southeast portion of Central Europe at the cross roads of several high and low pressure centers that form regularly at the borders. The influence of these air masses is altered by the presence in the central regions of the Carpathian mountain chain resulting in a diverse climate with average annual rain fall amounts between 350 to 1,400 mm and average annual temperatures between 2 and 11.5°C. ii) At the national level, almost all soils in the international classification system are present in Romania; each soil type having specific properties and characteristics. iii) On approximately 12.5 million ha (7.5 million ha arable), soil fertility is adversely affected by erosion, acidity, low humus content, extreme texture (clay, sand), excessive moisture, chemical pollution etc. These natural and anthropogenic factors dramatically influence agricultural production. Furthermore, soil, climate, topography, etc. vary widely not only across the country, but also on smaller scales, even across fields within the same farm. In Steppe zone limitative climatic factors, which require differentiation towards soil management use, include: long periods of drought, high temperatures, high frequency winds (wind erosion in area of sands), low relative air humidity, and harsh frosts during winter. Negative phenomena most commonly encountered in this area are salinization, excess water, temporary

  19. Effects of endurance exercise training on the motor and non-motor features of Parkinson's disease: a review.

    Science.gov (United States)

    Lamotte, Guillaume; Rafferty, Miriam R; Prodoehl, Janey; Kohrt, Wendy M; Comella, Cynthia L; Simuni, Tanya; Corcos, Daniel M

    2015-01-01

    Despite the benefits of medications and surgical interventions for Parkinson's disease (PD), these treatments are not without complications and neuroprotective strategies are still lacking. Therefore, there is a need for effective alternative approaches to treat motor and non-motor symptoms in PD. During the last decade, several studies have investigated endurance exercise training as a potential treatment for individuals with PD. This paper reviews the therapeutically beneficial effects of endurance exercise training on motor and non-motor symptoms in PD. First, we performed a systematic review of the literature on the effects of endurance exercise training on motor and non-motor signs of parkinsonism, functional outcomes including gait, balance and mobility, depression and fatigue, quality of life and perceived patient improvement, cardiorespiratory function, neurophysiological measures, and motor control measures in PD. Second we performed a meta-analysis on the motor section of the UPDRS. Then, we focused on several important factors to consider when prescribing endurance exercise training in PD such as intensity, duration, frequency, specificity and type of exercise. In addition, we identified current knowledge gaps regarding endurance exercise training in PD and made suggestions for future research. A total of eight randomized controlled trials met the inclusion criteria and were reviewed. This systematic review synthesizes evidence that endurance exercise training at a sufficiently high level enhances cardiorespiratory capacity and endurance by improving VO2 max and gait in moderately to mildly affected individuals with PD. However, there is not yet a proven effect of endurance exercise training on specific features of PD such as motor signs of parkinsonism. Endurance exercise training improves physical conditioning in PD patients; however, to date, there is insufficient evidence to include endurance exercise training as a specific treatment for PD. There is

  20. Range and Endurance Tradeoffs on Personal Rotorcraft Design

    Science.gov (United States)

    Snyder, Christopher A.

    2016-01-01

    Rotorcraft design has always been a challenging tradeoff among overall size, capabilities, complexity, and other factors based on available technology and customer requirements. Advancements in propulsion, energy systems and other technologies have enabled new vehicles and missions; complementary advances in analysis methods and tools enable exploration of these enhanced vehicles and the evolving mission design space. A system study was performed to better understand the interdependency between vehicle design and propulsion system capabilities versus hover loiter requirements and range capability. Three representative vertical lift vehicles were developed to explore the tradeoff in capability between hover efficiency versus range and endurance capability. The vehicles were a single-main rotor helicopter, a tilt rotor, and a vertical take-off and landing (VTOL) aircraft. Vehicle capability was limited to two or three people (including pilot or crew) and maximum range within one hour of flight (100-200 miles, depending on vehicle). Two types of propulsion and energy storage systems were used in this study. First was traditional hydrocarbon-fueled cycles (such as Otto, diesel or gas turbine cycles). Second was an all-electric system using electric motors, power management and distribution, assuming batteries for energy storage, with the possibility of hydrocarbon-fueled range extenders. The high power requirements for hover significantly reduced mission radius capability. Loiter was less power intensive, resulting in about 12 the equivalent mission radius penalty. With so many design variables, the VTOL aircraft has the potential to perform well for a variety of missions. This vehicle is a good candidate for additional study; component model development is also required to adequately assess performance over the design space of interest.

  1. Is static hyperinflation a limiting factor during exercise in adolescents with cystic fibrosis?

    Science.gov (United States)

    Werkman, M S; Hulzebos, H J; Arets, H G M; van der Net, J; Helders, P J M; Takken, T

    2011-02-01

    Increased work of breathing is considered to be a limiting factor in patients with cystic fibrosis (CF) performing aerobic exercise. We hypothesized that adolescents with CF and with static hyperinflation are more prone to a ventilatorily limited exercise capacity than non-static hyperinflated adolescents with CF. Exercise data of 119 adolescents with CF [range 12-18 years], stratified for static hyperinflation, defined as ratio of residual volume to total lung capacity (RV/TLC) > 30%, were obtained during a progressive bicycle ergometer test with gas analysis and analyzed for ventilatory limitation. Static hyperinflation showed a significant, though weak association (Φ 0.38; P 0.70; FEV(1)  hyperinflation showed an increase to Φ 0.49 (P  50%. In adolescents with static hyperinflation, peak work rate (W(peak) ; 3.1 ± 0.7 W/kg (75.1 ± 17.3% of predicted), peak oxygen uptake (VO(2peak) /kg (ml/min/kg); 39.2 ± 9.2 ml/min/kg (91.0 ± 20.3% of predicted), peak heart rate (HR(peak) ; 176 ± 19 beats/min) were significantly (P hyperinflated adolescents (W(peak) 3.5 ± 0.5 W/kg (81.4 ± 10.0% of predicted)); VO(2peak) /kg (ml/min/kg); 43.1 ± 7.5 ml/min/kg (98.0 ± 15.1% of predicted); and HR(peak) 185 ± 14 beats/min). Additionally, no difference was found in the degree of association of FEV(1) (%) and RV/TLC (%) with VO(2peak) /kg(pred) and W(peak) /kg(Pred) , but we found the RV/TLC (%) to be a slightly stronger predictor of VO(2peak) /kg(pred) and W(peak) /kg(Pred) than FEV(1) (%). These results indicate that the presence of static hyperinflation in adolescents with CF by itself does not strongly influence ventilatory constraints during exercise and that static hyperinflation is only a slightly stronger predictor of W(peak) /kg(Pred) and VO(2peak) /kg(Pred) than airflow obstruction (FEV(1) (%)).

  2. Anatomy of a bottleneck: diagnosing factors limiting population growth in the Puerto Rican parrot

    Science.gov (United States)

    Beissenger, S.R.; Wunderle, J.M.; Meyers, J.M.; Saether, B.-E.; Engen, S.

    2008-01-01

    captive young into wild nests), diminishing the importance of nest failure as a limiting factor. Annual survival has been periodically reduced by catastrophes (hurricanes), which have greatly constrained population growth, but survival rates were high under non-catastrophic conditions. Although the importance of factors maintaining the Puerto Rican Parrot bottleneck varied throughout the 30-year period of study, we determined their long-term influence using LSA simulations to correlate variation in demographic rates with variation in population growth (k). The bottleneck appears to have been maintained primarily by periodic catastrophes (hurricanes) that reduced adult survival, and secondarily by environmental and/or behavioral factors that resulted in a failure of many adults to nest. The influence of inbreeding through reduced hatching success played a much less significant role, even when additional effects of inbreeding on the production and mortality of young were incorporated into the LSA. Management actions needed to speed recovery include (1) continued nest guarding to minimize the effects of nest failure due to nongenetic causes; (2) creating a second population at another location on the island --a process that was recently initiated--to reduce the chance that hurricane strikes will cause extinction; and (3) determining the causes of the low percentage of breeders in the population and ameliorating them, which would have a large impact on population growth.

  3. Performance and Endocrine Responses to Differing Ratios of Concurrent Strength and Endurance Training.

    Science.gov (United States)

    Jones, Thomas W; Howatson, Glyn; Russell, Mark; French, Duncan N

    2016-03-01

    The present study examined functional strength and endocrine responses to varying ratios of strength and endurance training in a concurrent training regimen. Thirty resistance trained men completed 6 weeks of 3 d·wk of (a) strength training (ST), (b) concurrent strength and endurance training ratio 3:1 (CT3), (c) concurrent strength and endurance training ratio 1:1 (CT1), or (d) no training (CON). Strength training was conducted using whole-body multijoint exercises, whereas endurance training consisted of treadmill running. Assessments of maximal strength, lower-body power, and endocrine factors were conducted pretraining and after 3 and 6 weeks. After the intervention, ST and CT3 elicited similar increases in lower-body strength; furthermore, ST resulted in greater increases than CT1 and CON (all p ≤ 0.05). All training conditions resulted in similar increases in upper-body strength after training. The ST group observed greater increases in lower-body power than all other conditions (all p ≤ 0.05). After the final training session, CT1 elicited greater increases in cortisol than ST (p = 0.008). When implemented as part of a concurrent training regimen, higher volumes of endurance training result in the inhibition of lower-body strength, whereas low volumes do not. Lower-body power was attenuated by high and low frequencies of endurance training. Higher frequencies of endurance training resulted in increased cortisol responses to training. These data suggest that if strength development is the primary focus of a training intervention, frequency of endurance training should remain low.

  4. Effects of strength training on endurance capacity in top-level endurance athletes

    DEFF Research Database (Denmark)

    Aagaard, P; Andersen, J L

    2010-01-01

    The effect of concurrent strength (S) and endurance (E) training on adaptive changes in aerobic capacity, endurance performance, maximal muscle strength and muscle morphology is equivocal. Some data suggest an attenuated cardiovascular and musculoskeletal response to combined E and S training......-term endurance performance in endurance-trained subjects, ranging from moderately trained individuals to elite top-level athletes. It is concluded that strength training can lead to enhanced long-term (>30 min) and short-term (......, while other data show unimpaired or even superior adaptation compared with either training regime alone. However, the effect of concurrent S and E training only rarely has been examined in top-level endurance athletes. This review describes the effect of concurrent SE training on short-term and long...

  5. Effects of strength training on endurance capacity in top-level endurance athletes

    DEFF Research Database (Denmark)

    Aagaard, P; Andersen, J L

    2010-01-01

    , while other data show unimpaired or even superior adaptation compared with either training regime alone. However, the effect of concurrent S and E training only rarely has been examined in top-level endurance athletes. This review describes the effect of concurrent SE training on short-term and long......The effect of concurrent strength (S) and endurance (E) training on adaptive changes in aerobic capacity, endurance performance, maximal muscle strength and muscle morphology is equivocal. Some data suggest an attenuated cardiovascular and musculoskeletal response to combined E and S training......-term endurance performance in endurance-trained subjects, ranging from moderately trained individuals to elite top-level athletes. It is concluded that strength training can lead to enhanced long-term (>30 min) and short-term (...

  6. Transport and homeostasis of potassium and phosphate: limiting factors for sustainable crop production.

    Science.gov (United States)

    Luan, Mingda; Tang, Ren-Jie; Tang, Yumei; Tian, Wang; Hou, Congong; Zhao, Fugeng; Lan, Wenzhi; Luan, Sheng

    2017-06-01

    Potassium (K) and phosphate (Pi) are both macronutrients essential for plant growth and crop production, but the unrenewable resources of phosphorus rock and potash have become limiting factors for food security. One critical measure to help solve this problem is to improve nutrient use efficiency (NUE) in plants by understanding and engineering genetic networks for ion uptake, translocation, and storage. Plants have evolved multiple systems to adapt to various nutrient conditions for growth and production. Within the NUE networks, transport proteins and their regulators are the primary players for maintaining nutrient homeostasis and could be utilized to engineer high NUE traits in crop plants. A large number of publications have detailed K+ and Pi transport proteins in plants over the past three decades. Meanwhile, the discovery and validation of their regulatory mechanisms are fast-track topics for research. Here, we provide an overview of K+ and Pi transport proteins and their regulatory mechanisms, which participate in the uptake, translocation, storage, and recycling of these nutrients in plants. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  7. Embracing the emerging precision agriculture technologies for site-specific management of yield-limiting factors.

    Science.gov (United States)

    Melakeberhan, H

    2002-09-01

    Precision agriculture (PA) is providing an information revolution using Global Positioning (GPS) and Geographic Information (GIS) systems and Remote Sensing (RS). These technologies allow better decision making in the management of crop yield-limiting biotic and abiotic factors and their interactions on a site-specific (SSM) basis in a wide range of production systems. Characterizing the nature of the problem(s) and public education are among the challenges that scientists, producers, and industry face when adapting PA technologies. To apply SSM, spatio-temporal characteristics of the problem(s) need to be determined and variations within a field demonstrated. Spatio-temporal characteristics of a given pathogen or pest problem may be known but may not be the only or primary cause of the problem. Hence, exact cause-and-effect relationships need to be established by incorporating GIS, GPS, and RS-generated data as well as possible interactions. Exploiting the potential of PA technologies in sustainable ways depends on whether or not we first ask ''Are we doing the right thing?'' (strategic) as opposed to ''Are we doing it right?'' (tactical).

  8. Factors responsible for the emergence of arboviruses; strategies, challenges and limitations for their control.

    Science.gov (United States)

    Liang, Guodong; Gao, Xiaoyan; Gould, Ernest A

    2015-03-01

    Slave trading of Africans to the Americas, during the 16th to the 19th century was responsible for the first recorded emergence in the New World of two arthropod-borne viruses (arboviruses), yellow fever virus and dengue virus. Many other arboviruses have since emerged from their sylvatic reservoirs and dispersed globally due to evolving factors that include anthropological behaviour, commercial transportation and land-remediation. Here, we outline some characteristics of these highly divergent arboviruses, including the variety of life cycles they have developed and the mechanisms by which they have adapted to evolving changes in habitat and host availability. We cite recent examples of virus emergence that exemplify how arboviruses have exploited the consequences of the modern human lifestyle. Using our current understanding of these viruses, we also attempt to demonstrate some of the limitations encountered in developing control strategies to reduce the impact of future emerging arbovirus diseases. Finally, we present recommendations for development by an international panel of experts reporting directly to World Health Organization, with the intention of providing internationally acceptable guidelines for improving emerging arbovirus disease control strategies. Success in these aims should alleviate the suffering and costs encountered during recent decades when arboviruses have emerged from their sylvatic environment.

  9. Theory of factors limiting high gradient operation of warm accelerating structures

    Energy Technology Data Exchange (ETDEWEB)

    Nusinovich, Gregory S. [University of Maryland; Antonsen, Thomas M. [University of Maryland; Kishek, Rami [University of Maryland

    2014-07-25

    This final report summarizes the research performed during the time period from 8/1/2010 to 7/31/2013. It consists of two parts describing our studies in two directions: (a) analysis of factors limiting operation of dielectric-loaded accelerating (DLA) structures where the main problem is the occurrence of multipactor on dielectric surfaces, and (b) studies of effects associated with either RF magnetic or RF electric fields which may cause the RF breakdown in high-gradient metallic accelerating structures. In the studies of DLA structures, at least, two accomplishments should be mentioned: the development of a 3D non-stationary, self-consistent code describing the multipactor phenomena and yielding very good agreement with some experimental data obtained in joint ANL/NRL experiments. In the metallic structures, such phenomena as the heating and melting of micro-particles (metallic dust) by RF electric and magnetic fields in single-shot and rep-rate regimes is analyzed. Also, such processes in micro-protrusions on the structure surfaces as heating and melting due to the field emitted current and the Nottingham effect are thoroughly investigated with the account for space charge of emitted current on the field emission from the tip.

  10. The effect of food limitation on immunity factors and disease resistance in the western tent caterpillar.

    Science.gov (United States)

    Myers, Judith H; Cory, Jenny S; Ericsson, Jerry D; Tseng, Michelle L

    2011-11-01

    Epizootics of nucleopolyhedrovirus characterize declines of cyclic populations of western tent caterpillars, Malacosoma pluviale californicum. In field populations, infection can be apparently lacking in one generation and high in the next. This may suggest an increase in the susceptibility to infection of larvae at peak density or the triggering of a vertically transmitted virus. Here, we test the hypothesis that reduced food availability, as may occur during population outbreaks of tent caterpillars, influences the immunocompetence of larvae and increases their susceptibility to viral infection. We compared immunity factors, hemolymph phenoloxidase and hemocyte numbers, and the susceptibility to nucleopolyhedroviral infection of fifth instar larvae that were fully or partially fed as fourth instars. To determine if maternal or transgenerational influences occurred, we also determined the susceptibility of the offspring of the treated parents to viral infection. Food limitation significantly reduced larval survival, development rate, larval and pupal mass, moth fecundity and levels of hemolymph phenoloxidase, but not the numbers of hemocytes. Neither the food-reduced larvae nor their offspring were more susceptible to viral infection and were possibly even less susceptible at intermediate viral doses. Food reduction did not activate latent or covert viral infection of larvae as might be expected as a response to stress. We conclude that reducing the food intake of fourth instar larvae to an extent that had measurable and realistic impacts on their life history characteristics was not translated into increased susceptibility to viral infection.

  11. Biodiversities and limiting factors of Lashgardar Protected Area (LPA, Hamadan Province, Iran

    Directory of Open Access Journals (Sweden)

    MAHDI REYAHI KHORAM

    2010-10-01

    Full Text Available Reyahi-Khoram M, Norisharikabad V (2011 Biodiversities and limiting factors of Lashgardar Protected Area (LPA, Hamadan Province, Iran. Biodiversitas 12: 216-221. Lashgardar Protected Area (LPA located in Hamadan Province in Iran, it is a mountainous and plain area and proximal to Malayer Township. In 1991, the region was known as a protected area for increasing wild animals' population. This research has been conducted during 2001 through 2009. Plant and animal species of the region were identified and statistics of the population of animal flagship species were gathered. In this research, valid academic resources were used for identification of animal and plant species. Geographic Information System (GIS has been used to evaluate the land as main tool. The software used was Arc View (version 3.2a scale was 1/50,000. Due to cold mountainous climate, the region is covered by a wide diversity of trees, shrubs, grasses and herbs. There were 18 species of mammals as well as 75 bird species in LPA. Most abundant mammalian population belongs to wild sheep (558 animals and the second abundance was related to wild goat (515 animals. Also, the most abundant bird species belong to ortolans. Result of the present study showed that construction of connection roads in vicinity the region, establishment of factories inside and around the region, military garrison, unauthorized grazing, unlawful hunting, and Ahangaran mine and rail road have all exposed put LPA to serious threat and danger.

  12. Elevated hair cortisol concentrations in endurance athletes.

    Science.gov (United States)

    Skoluda, Nadine; Dettenborn, Lucia; Stalder, Tobias; Kirschbaum, Clemens

    2012-05-01

    Engaging in intensive aerobic exercise, specifically endurance sports, is associated with HPA axis activation indicated by elevated cortisol levels. Whether the repeated short-term elevations in cortisol levels result in higher long-term cortisol exposure of endurance athletes has been difficult to examine since traditional methods of cortisol assessments (saliva, blood, urine) reflect only relatively short time periods. Hair segment analysis provides a new method to assess cumulative cortisol secretion over prolonged time periods in a retrospective fashion. The aim of this study was to investigate cumulative cortisol secretion over several months reflecting intensive training and competitive races by examining hair cortisol levels of endurance athletes. Hair samples were obtained from 304 amateur endurance athletes (long-distance runners, triathletes, cyclists) and 70 controls. Cortisol concentrations were determined in the first to third 3-cm hair segments most proximal to the scalp. In addition, self-report measures of training volume were obtained. Endurance athletes exhibited higher cortisol levels in all three hair segments compared to controls (pathletes is associated with elevated cortisol exposure over prolonged periods of time. These findings may have important implications with regard to somatic and mental health of athletes which should be investigated in future research.

  13. Therapeutic targeting of epidermal growth factor receptor in human cancer: successes and limitations%Therapeutic targeting of epidermal growth factor receptor in humancancer: successes and limitations

    Institute of Scientific and Technical Information of China (English)

    Jill Wykosky; Tim Fenton; Frank Furnari; Webster K. Cavenee

    2011-01-01

    Epidermal growth factor receptor (EGFR) is one of the most commonly altered genes in human cancer by way of over-expression, amplification, and mutation. Targeted inhibition of EGFR activity suppresses signal transduction pathways which control tumor cell growth, proliferation, and resistance to apoptosis. Small molecule tyrosine kinase inhibitors and monoclonal antibodies are among the most common EGFR-targeting agents and have been used clinically for treating various malignancies. This review discusses the successes and challenges of targeting EGFR in human cancer. The genetic alterations of EGFR tend to occur more often in some solid tumors than others, as do the mechanisms of resistance to targeted inhibition. The clinical and basic science experiences with these agents thus far have important implications for the future of therapeutic targeting of EGFR.

  14. Heavy-to-Light Form Factors in the Final Hadron Large Energy Limit Covariant Quark Model Approach

    CERN Document Server

    Charles, J; Oliver, L; Pène, O; Raynal, J C

    1999-01-01

    We prove the full covariance of the heavy-to-light weak current matrix elements based on the Bakamjian-Thomas construction of relativistic quark models, in the heavy mass limit for the parent hadron and the large energy limit for the daughter one. Moreover, this quark model representation of the heavy-to-light form factors fulfills the general relations that were recently argued to hold in the corresponding limit of QCD, namely that there are only three independent form factors describing the B -> pi (rho) matrix elements, as well as the factorized scaling law sqrt(M)z(E) of the form factors with respect to the heavy mass M and large energy E. These results constitute another good property of the quark models à la Bakamjian-Thomas, which were previously shown to exhibit covariance and Isgur-Wise scaling in the heavy-to-heavy case.

  15. Updating Environmental Media Concentration Limits and Uncertainty factors in the ERICA Tool

    Energy Technology Data Exchange (ETDEWEB)

    Brown, J.E.; Hosseini, A. [Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Oesteraas (Norway); Alfonso, B.; Avila, R. [Facilia AB, S-167 51 Bromma (Sweden); Beresford, N.A. [Centre for Ecology and Hydrology, CEH-Lancaster, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA 1 4AP (United Kingdom); Copplestone, D. [Dept. Biological and Environmental Sciences, University of Stirling, Stirling, FK9 4LA (United Kingdom)

    2014-07-01

    Tiered approaches have become a standard means of structuring information in the process of conducting environmental risk assessments. For cases involving the assessment of impacts on wildlife from ionising radiation, the ERICA integrated approach and its supporting software (The ERICA Tool) provides such a structure, splitting the system into two generic screening tiers and a third site-specific tier. The first Tier is very simple, based around Environmental Media Concentration Limits, EMCLs, and requires minimal input from the assessor. The second Tier, although still a screening tier, calculates dose rates and requires more detailed input from the assessor allowing for scrutiny and editing of default parameters in the process. A key element of Tier 2 involves the application of Uncertainty Factors, UFs. Such factors reflect our knowledge concerning probability distribution functions and provide a way of incorporating conservatism into the assessment by considering high percentile values in underlying parameters. Following its launch in 2007, there have been significant developments regarding certain components of the ERICA integrated approach. Most notably, an extended international collation of concentration ratio data has precipitated the need to update parameter values in the Tools databases. In addition, more considered guidance has been developed with regards to filling knowledge gaps in the absence of transfer data. Furthermore, the efficacy of the methods used in assigning probability distribution functions has been questioned leading to an acknowledgement from the developers that the methods were not described in enough detail nor were the justifications for applying the selected approach provided in a convincing way. This has implications for the EMCL values which are derived probabilistically using parameters including concentration ratios. Furthermore, there are implications for UF derivation that relies upon a robust consideration of underlying

  16. Blue duiker Philantomba monticola densities in the Tsitsikamma National Park and probable factors limiting these populations

    Directory of Open Access Journals (Sweden)

    N. Hanekom

    1991-09-01

    Full Text Available Numbers of blue duikers recorded on 157 and 28 variable width transect counts, done over a two year period in the Tsitsikamma Coastal National Park (TCNP and Tsitsikamma Forest National Park (TFNP respectively, did not differ significantly {P > 0,10 with seasons (summer v. winter. Population density estimates from transects were similar to those from game drives (0,18 v. 0,19 duikers/ha (TCNP and 0,13 v. 0,17 duikers/ha (TFNP; P >0,10, higher than from faecal pellet counts (P < 0,10 and at least three times lower than estimates from the Kenneth Stainbank Nature Reserve and Umdoni Park in Natal. Factors contributing to the low population densities in the Tsitsikamma national parks were investigated. Twentyseven and seven percent of leopard (25 and caracal (12 scats respectively analyzed contained blue duiker remains, but predator numbers appear to be low. Forest characteristics were investigated, and results from this and other studies suggest that undergrowth cover does not markedly influence blue duiker densities in the southern Cape forests. Field and stomach analysis indicate that blue duikers feed primarily on freshly fallen leaves and fruit, and are selective foragers. In the Tsitsikamma national parks (TNPs the frequency of occurrence of trees known to be palatable to duikers are low, while less than 45 percent of the dominant tree species fruit fully annually. This apparent scarcity of food, the low numbers of antelope species and individuals in these forests and results from duiker research in Zaire, suggest that habitat rather than predation is limiting duiker numbers in the Tsitsikamma national parks.

  17. Weathering as the limiting factor of denudation in the Western escarpment of the Andes

    Science.gov (United States)

    Abbühl, L. M.; Schlunegger, F.; Kracht, O.; Ramseyer, K.; Rieke-Zapp, D.; Aldahan, A.; von Blanckenburg, F.

    2009-04-01

    additional river profile knickzone in the transition zone between the easterlies and the westerlies. Analysis of 10Be in quartz of river-born sand and of bedrock reveals that denudation correlates positively with the present-day rainfall pattern related to the easterlies. Denudation rates in the headwaters range from 0.14 mm/year in Northern Peru down to 0.05 mm/yr in Northern Chile (Kober et al., 2007). In addition, 10Be-based denudation rates reveal a decreasing trend from the Cordillera to the Pacific coast that positively correlates with the decreasing precipitation rate, irrespective of the nature of the bedrock. Interestingly, the 10Be analysis conducted in the Piura system reveals no influence of the episodic precipitation in relation to El Niño on the sediment production rates. In summary, the pattern of denudation rates together with morphometric observations and quantitative denudation rate estimates strongly hints at weathering being the driving but also limiting factor of denudation. Accordingly, in the western Peruvian Andes, sediment production and export are most probably controlled by the pattern and rate of precipitation. Kober, F., Ivy-Ochs, S., Schlunegger, F., Baur, H., Kubik, P. W., and Wieler, R. (2007). Denudation rates and a topography-driven rainfall threshold in northern Chile: Multiple cosmogenic nuclide data and sediment yield budgets. Geomorphology 83, 97-120.

  18. Current Scientific Evidence for a Polarized Cardiovascular Endurance Training Model.

    Science.gov (United States)

    Hydren, Jay R; Cohen, Bruce S

    2015-12-01

    Recent publications have provided new scientific evidence for a modern aerobic or cardiovascular endurance exercise prescription that optimizes the periodization cycle and maximizes potential endurance performance gains in highly trained individuals. The traditional threshold, high volume, and high-intensity training models have displayed limited improvement in actual race pace in (highly) trained individuals while frequently resulting in overreaching or overtraining (physical injury and psychological burnout). A review of evidence for replacing these models with the proven polarized training model seems warranted. This review provides a short history of the training models, summarizes 5 key studies, and provides example training programs for both the pre- and in-season periods. A polarized training program is characterized by an undulating nonlinear periodization model with nearly all the training time spent at a "light" (≤13) and "very hard" (≥17) pace with very limited time at "hard" (14-16) or race pace (6-20 Rating of Perceived Exertion [RPE] scale). To accomplish this, the polarization training model has specific high-intensity workouts separated by one or more long slow distance workouts, with the exercise intensity remaining below ventilatory threshold (VT) 1 and/or blood lactate of less than 2 mM (A.K.A. below race pace). Effect sizes for increasing aerobic endurance performance for the polarized training model are consistently superior to that of the threshold training model. Performing a polarized training program may be best accomplished by: going easy on long slow distance workouts, avoiding "race pace" and getting after it during interval workouts.

  19. Antioxidant supplementation does not alter endurance training adaptation

    DEFF Research Database (Denmark)

    Yfanti, Christina; Åkerström, Thorbjörn; Nielsen, Søren

    2010-01-01

    BACKGROUND: There is a considerable commercial market, especially within the sports community, claiming the need for antioxidant supplementation. One argument for antioxidant supplementation in sports is that physical exercise is associated with increased reactive oxygen and nitrogen species (RONS...... measured. CONCLUSION: Our results suggest that administration of vitamins C and E to individuals with no prior vitamin deficiencies has no effect on physical adaptations to strenuous endurance training.......) production, which may cause cell damage. However, RONS production may also activate redox sensitive signaling pathways and transcription factors, which subsequently may promote training adaptation. PURPOSE: Our aim was to investigate the effects of combined vitamin C and E supplementation to healthy...

  20. Effects of Endurance and Circuit Resistance Trainings on Lipid Profile, Heart Rate, and Hematological Parameters in Obese Male Students

    Directory of Open Access Journals (Sweden)

    Mehdi Mogharnasi

    2014-12-01

    Full Text Available Studies have shown that different exercise ways are of the most important factors that affect cardiovascular risk factors and hematological parameters. This present paper aims to study the effects of two methods of endurance and resistance training on lipid profiles, heart rate, and hematological parameters in obese male students. 36 obese students were purposefully selected and randomly divided into three groups of 12 including endurance exercise, resistance exercise, and control. Exercise program was performed 3 times a week for 8 weeks, with a specific duration and intensity in both endurance and resistance exercise groups. Blood sampling was done after 14 fasting before the trial and 48 hours after the last training session. Results showed that both resistance and endurance exercises significantly increased HDL-C, Hct, and Hb and significantly decreased TC, TG, and resting heart rate (P>0.05. Also, Resistance exercise significantly increased the PLT and decreased LDL-C (P>0.05. However, WBC and RBC showed no significant change in the resistance and endurance exercise groups (P>0.05. In addition, no significant difference was observed between endurance and resistance exercise (P>0.05. In general, both endurance and resistance exercises can affect the lipid profile and hematological parameters and also reduce the resting heart rate. Therefore, they can be considered as an appropriate and non-medication approaches to prevent and reduce the incidence of cardiovascular diseases and obesity-related disorders in obese male adolescents.

  1. A study of several factors governing the fatigue limits of austempered ductile cast iron with various microstructures

    Science.gov (United States)

    Kim, Jinhak; Kim, Sangtae; Kim, Mingun

    2000-06-01

    The effects the leading factors bearing on fatigue limits were investigated with three kinds of ductile iron specimens various microstructures. As a result of examination, the fatigue limits in relationship to hardness and tensile strength, the expected higher improvement for fatigue limits in the case of the high strength specimens that experienced austempering treatment are not observed in comparison with the specimens treated with stress relief treatment. The estimated maximum defect size is one of the important parameters in predicting and evaluating fatigue limits for three different heat-treated ductile cast irons. Also, a quantitative relationship can be established between the fatigue limit and maximum defect size. Moreover, it is possible to explain the difference in fatigue limits in the three ductile cast irons by application of the rates of non-propagating crack which connects the adjacent graphite nodules before it stops.

  2. Biodegradation of petroleum in the marine environment: limiting factors and methods of enhancement

    National Research Council Canada - National Science Library

    Lee, K; Levy, E.M

    1986-01-01

    .... Maximal biodegradation rates are rarely attained under natural environmental conditions, and extensive studies have concluded that the degradation of petroleum in the marine environment is limited...

  3. Using molecular classification to predict gains in maximal aerobic capacity following endurance exercise training in humans

    DEFF Research Database (Denmark)

    Timmons, James A; Knudsen, Steen; Rankinen, Tuomo

    2010-01-01

    A low maximal oxygen consumption (VO2max) is a strong risk factor for premature mortality. Supervised endurance exercise training increases VO2max with a very wide range of effectiveness in humans. Discovering the DNA variants that contribute to this heterogeneity typically requires substantial s...... of genetic biomarkers, sufficiently discrete for diagnostic purposes, for a range of physiological and pharmacological phenotypes in humans.......A low maximal oxygen consumption (VO2max) is a strong risk factor for premature mortality. Supervised endurance exercise training increases VO2max with a very wide range of effectiveness in humans. Discovering the DNA variants that contribute to this heterogeneity typically requires substantial...... association analysis yields a strongly validated molecular predictor with meaningful explanatory power. VO2max responses to endurance training can be predicted by measuring a approximately 30-gene RNA expression signature in muscle prior to training. The general approach taken could accelerate the discovery...

  4. Structural state scale-dependent physical characteristics and endurance of cermet composite for cutting metal

    Energy Technology Data Exchange (ETDEWEB)

    Ovcharenko, V. E., E-mail: ovcharenko.ove45@mail.ru [Institute of Strength Physics and Materials Science SB RAS, Tomsk, 634055, Russia and Institute of Heavy-Current Electronics SB RAS, Tomsk, 634055 (Russian Federation); Ivanov, Yu. F., E-mail: ivanov.yufi55@mail.ru [Institute of Heavy-Current Electronics SB RAS, Tomsk, 634055, Russia and National Research Tomsk Polytechnic University, Tomsk, 634050 (Russian Federation); Mohovikov, A. A., E-mail: mohovikov.maa28@rambler.ru [Institute of Heavy-Current Electronics SB RAS, Tomsk, 634055 (Russian Federation); Baohai, Yu, E-mail: baohai.bhyu@imr.ac.cn, E-mail: yanhui.yhzhao@imr.ac.cn; Zhao, Yanhui, E-mail: baohai.bhyu@imr.ac.cn, E-mail: yanhui.yhzhao@imr.ac.cn [Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, 110016 (China)

    2014-11-14

    A structural-phase state developed on the surface of a TiC/Ni–Cr–Al cermet alloy under superfast heating and cooling produced by pulse electron beam melting has been presented. The effect of the surface’s structural state multimodality on the temperature dependencies of the friction and endurance of the cermet tool in cutting metal has been investigated. The high-energy flux treatment of subsurface layers by electron beam pulses in argon-containing gas discharge plasma serves to improve the endurance of metal cutting tools manifold (by a factor of 6), to reduce the friction via precipitation of secondary 200 nm carbides in binder interlayers. It is possible to improve the cermet tool endurance for cutting metal by a factor of 10–12 by irradiating the cermet in a reactive nitrogen-containing atmosphere with the ensuing precipitation of nanosize 50 nm AlN particles in the binder interlayers.

  5. Caffeine and exercise: metabolism, endurance and performance.

    Science.gov (United States)

    Graham, T E

    2001-01-01

    Caffeine is a common substance in the diets of most athletes and it is now appearing in many new products, including energy drinks, sport gels, alcoholic beverages and diet aids. It can be a powerful ergogenic aid at levels that are considerably lower than the acceptable limit of the International Olympic Committee and could be beneficial in training and in competition. Caffeine does not improve maximal oxygen capacity directly, but could permit the athlete to train at a greater power output and/or to train longer. It has also been shown to increase speed and/or power output in simulated race conditions. These effects have been found in activities that last as little as 60 seconds or as long as 2 hours. There is less information about the effects of caffeine on strength; however, recent work suggests no effect on maximal ability, but enhanced endurance or resistance to fatigue. There is no evidence that caffeine ingestion before exercise leads to dehydration, ion imbalance, or any other adverse effects. The ingestion of caffeine as coffee appears to be ineffective compared to doping with pure caffeine. Related compounds such as theophylline are also potent ergogenic aids. Caffeine may act synergistically with other drugs including ephedrine and anti-inflammatory agents. It appears that male and female athletes have similar caffeine pharmacokinetics, i.e., for a given dose of caffeine, the time course and absolute plasma concentrations of caffeine and its metabolites are the same. In addition, exercise or dehydration does not affect caffeine pharmacokinetics. The limited information available suggests that caffeine non-users and users respond similarly and that withdrawal from caffeine may not be important. The mechanism(s) by which caffeine elicits its ergogenic effects are unknown, but the popular theory that it enhances fat oxidation and spares muscle glycogen has very little support and is an incomplete explanation at best. Caffeine may work, in part, by

  6. New records in aerobic power among octogenarian lifelong endurance athletes

    National Research Council Canada - National Science Library

    Scott Trappe; Erik Hayes; Andrew Galpin; Leonard Kaminsky; Bozena Jemiolo; William Fink; Todd Trappe; Anna Jansson; Thomas Gustafsson; Per Tesch

    2013-01-01

    ...). The endurance athletes were cross-country skiers, including a former Olympic champion and several national/regional champions, with a history of aerobic exercise and participation in endurance events...

  7. Monitoring endurance athletes : A multidisciplinary approach

    NARCIS (Netherlands)

    Otter, Tina Ardi

    2016-01-01

    Endurance athletes seek for the optimal balance in training stress and recovery so they can perform at their best and avoid injuries. The PhD thesis of Ruby Otter at the School of Sport Studies (Hanze University of Applied Sciences) and the Center of Human Movement Sciences (UMCG, University of Gron

  8. Life-long endurance exercise in humans

    DEFF Research Database (Denmark)

    Mikkelsen, U R; Couppé, C; Karlsen, A

    2013-01-01

    Human aging is associated with a loss of skeletal muscle and an increase in circulating inflammatory markers. It is unknown whether endurance training (Tr) can prevent these changes. Therefore we studied 15 old trained (O-Tr) healthy males and, for comparison, 12 old untrained (O-Un), 10 Young-Tr...

  9. Piaget's Enduring Contribution to Developmental Psychology.

    Science.gov (United States)

    Beilin, Harry

    1992-01-01

    Describes Jean Piaget's transformation of society's conception of childhood thought. Emphasizes the enduring contribution to developmental psychology of Piaget's constructivism, his description of developmental mechanisms, his cognitivism, his explication of structural and functional analysis, and his addressing of epistemological issues and…

  10. Monitoring endurance athletes : A multidisciplinary approach

    NARCIS (Netherlands)

    Otter, Tina Ardi

    2016-01-01

    Endurance athletes seek for the optimal balance in training stress and recovery so they can perform at their best and avoid injuries. The PhD thesis of Ruby Otter at the School of Sport Studies (Hanze University of Applied Sciences) and the Center of Human Movement Sciences (UMCG, University of Gron

  11. Life-long endurance exercise in humans

    DEFF Research Database (Denmark)

    Mikkelsen, U R; Couppé, C; Karlsen, A;

    2013-01-01

    Human aging is associated with a loss of skeletal muscle and an increase in circulating inflammatory markers. It is unknown whether endurance training (Tr) can prevent these changes. Therefore we studied 15 old trained (O-Tr) healthy males and, for comparison, 12 old untrained (O-Un), 10 Young-Tr...

  12. Piaget's Enduring Contribution to Developmental Psychology.

    Science.gov (United States)

    Beilin, Harry

    1992-01-01

    Describes Jean Piaget's transformation of society's conception of childhood thought. Emphasizes the enduring contribution to developmental psychology of Piaget's constructivism, his description of developmental mechanisms, his cognitivism, his explication of structural and functional analysis, and his addressing of epistemological issues and…

  13. The Personal Meaning of Participation: Enduring Involvement.

    Science.gov (United States)

    McIntyre, N.

    1989-01-01

    Examines the personal meaning of participation, discussing recreation and consumer behavior literature, the development of an instrument to measure the concept, and the relationship between commitment to camping and choice of campground setting. Personal meaning of participation seems to be best represented by the concept of enduring involvement.…

  14. Simulating the physiology of athletes during endurance sports events: Modelling human energy conversion and metabolism

    NARCIS (Netherlands)

    Beek, J.H.G.M. van; Supandi, F.; Gavai, A.K.; Graaf, A.A. de; Binsl, T.W.; Hettling, H.

    2011-01-01

    The human physiological system is stressed to its limits during endurance sports competition events.We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We

  15. ‘The engine just started coughing!’ – Exploring endurance athletes’ experience of aging

    DEFF Research Database (Denmark)

    Ronkainen, Noora; Ryba, Tatiana; Nesti, Mark

    2013-01-01

    This research examines male endurance athletes’ experience of aging and/or reaching the limits of athletic development. More specifically, the current study aimed to explore how meanings attached to these experiences are connected with athletes’ career decision-making and possible athletic retire...

  16. Simulating the physiology of athletes during endurance sports events: Modelling human energy conversion and metabolism

    NARCIS (Netherlands)

    Beek, J.H.G.M. van; Supandi, F.; Gavai, A.K.; Graaf, A.A. de; Binsl, T.W.; Hettling, H.

    2011-01-01

    The human physiological system is stressed to its limits during endurance sports competition events.We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We calculate

  17. No Effect of Exercise Intensity on Appetite in Highly-Trained Endurance Women

    OpenAIRE

    Howe, Stephanie M; Taryn M. Hand; D. Enette Larson-Meyer; Kathleen J. Austin; Alexander, Brenda M.; Melinda M. Manore

    2016-01-01

    In endurance-trained men, an acute bout of exercise is shown to suppress post-exercise appetite, yet limited research has examined this response in women. The purpose of this study was to investigate the effect of exercise intensity on appetite and gut hormone responses in endurance-trained women. Highly-trained women (n = 15, 18–40 years, 58.4 ± 6.4 kg, VO2MAX = 55.2 ± 4.3 mL/kg/min) completed isocaloric bouts (500 kcals or 2093 kJ) of moderate-intensity (MIE, 60% VO2MAX) and high-intensity ...

  18. Constraints on the bulk Lorentz factor of Gamma-Ray Burst jets from Fermi/LAT upper limits

    CERN Document Server

    Nava, L; Longo, F; Celotti, A; Omodei, N; Vianello, G; Bissaldi, E; Piran, T

    2016-01-01

    It is largely recognized that Gamma-Ray Burst (GRB) jets involve ultra-relativistic motion. However, the value of the Lorentz factor Gamma_0 is still not clear and only lower limits are known for most bursts. We suggest here a new method to obtain upper limits on Gamma_0. The early high-energy synchrotron afterglow flux depends strongly on Gamma_0. Upper limits on GeV emission therefore provide uppers limit on Gamma_0. Applying this method to 190 Fermi GRBs that have not been detected by the Fermi-LAT we place upper limits on the high-energy afterglow flux, and in turn on Gamma_0. For bursts at a typical redshift z=2, we find values of the order of 200 (and above) for a homogeneous density medium, and in the range 100-400 for a wind-like medium. These upper limits are consistent with (and are very close to) lower limits and direct estimates inferred using other methods, suggesting that the typical Lorentz factors of GRB jets are of order a few hundred.

  19. Constraints on the bulk Lorentz factor of gamma-ray burst jets from Fermi /LAT upper limits

    Science.gov (United States)

    Nava, L.; Desiante, R.; Longo, F.; Celotti, A.; Omodei, N.; Vianello, G.; Bissaldi, E.; Piran, T.

    2017-02-01

    It is largely recognized that Gamma-Ray Burst (GRB) jets involve ultra-relativistic motion. However, the value of the Lorentz factor Gamma_0 is still not clear and only lower limits are known for most bursts. We suggest here a new method to obtain upper limits on Gamma_0. The early high-energy synchrotron afterglow flux depends strongly on Gamma_0. Upper limits on GeV emission therefore provide uppers limit on Gamma_0. Applying this method to 190 Fermi GRBs that have not been detected by the Fermi-LAT we place upper limits on the high-energy afterglow flux, and in turn on Gamma_0. For bursts at a typical redshift z=2, we find values of the order of 200 (and above) for a homogeneous density medium, and in the range 100-400 for a wind-like medium. These upper limits are consistent with (and are very close to) lower limits and direct estimates inferred using other methods, suggesting that the typical Lorentz factors of GRB jets are of order a few hundred.

  20. The Three Domains of Disgust Scale: Factor Structure, Psychometric Properties, and Conceptual Limitations

    Science.gov (United States)

    Olatunji, Bunmi O.; Adams, Thomas; Ciesielski, Bethany; David, Bieke; Sarawgi, Shivali; Broman-Fulks, Joshua

    2012-01-01

    This investigation examined the measurement properties of the Three Domains of Disgust Scale (TDDS). Principal components analysis in Study 1 (n = 206) revealed three factors of Pathogen, Sexual, and Moral Disgust that demonstrated excellent reliability, including test-retest over 12 weeks. Confirmatory factor analyses in Study 2 (n = 406)…

  1. The Three Domains of Disgust Scale: Factor Structure, Psychometric Properties, and Conceptual Limitations

    Science.gov (United States)

    Olatunji, Bunmi O.; Adams, Thomas; Ciesielski, Bethany; David, Bieke; Sarawgi, Shivali; Broman-Fulks, Joshua

    2012-01-01

    This investigation examined the measurement properties of the Three Domains of Disgust Scale (TDDS). Principal components analysis in Study 1 (n = 206) revealed three factors of Pathogen, Sexual, and Moral Disgust that demonstrated excellent reliability, including test-retest over 12 weeks. Confirmatory factor analyses in Study 2 (n = 406)…

  2. The effects of eight weeks of endurance training on BDNF, insulin and insulin resistance in rats

    Directory of Open Access Journals (Sweden)

    A zar

    2016-06-01

    Full Text Available Background & aim: Brain-derived neurotrophic factor (BDNF is one of the most important neurotrophin that it will lead to the development of metabolic syndrome. Brain-derived neurotrophic factor directly related to conditions such as epilepsy, Alzheimer's and depression. The purpose of this research was investigate effect of eight weeks endurance training on Neutrophic factor that derived from the rats' brain , Insulin and resistance to Insulin. Methods:  Statistical Society in this research consist of Male Sprague Dawley rats. Among them, 24 rats at 8 weeks of age and weight of 43/31 ± 72/280 grams were purchased from Pasteur Institute in Shiraz. Then transferred to the laboratory and randomly assigned to two experimental and control groups (endurance training. Also before the start of the study, the rats a period of one week to adapt to the new environment and the activities during the treadmill. During eight weeks the endurance exercise mice group running on treadmill machine without slope(zero percent slope with speeding 8 till 20 meter per minute and about 60 minute in each session and 3 session in a week. Control mice group during this time did not have any exercise activity. 24 hours after the last training session at the end of week the eighth, the rats sacrificed to measure the parameters studied until biochemical alterations resulting endurance investigate training effects. For analysis data, was used of independent T-test that was considered as significance level (a=0/05. Results: Analysis of the findings showed that Eight weeks of endurance training has not   significant effect on the Brain-derived neurotrophic factor in rat(p=0/011. Eight weeks endurance training leads to a significant reduction on Insulin (p=0/005 and eight weeks endurance training leads to significant reduction resistance to Insulin (p=0/001.  Discussion: Hence get conclusion that endurance training have significant effect on reduction of Insulin and don

  3. Is asymptomatic peripheral arterial disease associated with walking endurance in patients with COPD?

    Directory of Open Access Journals (Sweden)

    Sun KS

    2015-07-01

    Full Text Available Kuo-Shao Sun,1,2* Ming-Shian Lin,1,2* Yi-Jen Chen,1,2 Yih-Yuan Chen,3 Solomon Chih-Cheng Chen,4 Wei Chen1,5,6 1Division of Pulmonary and Critical Care Medicine, 2Department of Respiratory Care, Chang Gung University of Science and Technology, 3Department of Internal Medicine, 4Department of Medical Research, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chiayi, 5College of Nursing, Dayeh University, Changhua, 6Department of Respiratory Therapy, China Medical University, Taichung, Taiwan, Republic of China *These authors contributed equally to this work Objective: Symptomatic peripheral arterial disease (PAD is associated with impaired walking endurance in patients with chronic obstructive pulmonary disease (COPD. However, it is unknown whether asymptomatic PAD is associated with impaired walking endurance in patients with COPD. Methods: This prospective cross-sectional study enrolled 200 COPD patients (mean age: 70.9 years who volunteered to perform ankle-brachial index (ABI and 6-minute walk test (6MWT consecutively. Demographic data, lung function, dyspnea scales, and cardiovascular risk factors were recorded. The ABI was used to detect PAD (ABI <0.90. All patients were free of PAD symptoms at enrollment. Results: Of the 200 COPD patients, 17 (8.5% were diagnosed with asymptomatic PAD. The COPD patients without asymptomatic PAD did not walk significantly further on the 6MWT than the COPD patients with asymptomatic PAD (439±86 m vs 408±74 m, P=0.159. The strongest correlation with the distance walked on the 6MWT was Medical Research Council dyspnea scale (r2=-0.667, P<0.001, followed by oxygen-cost diagram (r2=0.582, P<0.001 and forced expiratory volume in 1 second (r2=0.532, P<0.001. In multivariate linear regression analysis, only age, forced expiratory volume in 1 second, and baseline pulse oximetry were independently correlated with the distance covered on the 6MWT (P<0.05. However, body mass index, baseline heart rate, and

  4. [Limiting a Medline/PubMed query to the "best" articles using the JCR relative impact factor].

    Science.gov (United States)

    Avillach, P; Kerdelhué, G; Devos, P; Maisonneuve, H; Darmoni, S J

    2014-12-01

    Medline/PubMed is the most frequently used medical bibliographic research database. The aim of this study was to propose a new generic method to limit any Medline/PubMed query based on the relative impact factor and the A & B categories of the SIGAPS score. The entire PubMed corpus was used for the feasibility study, then ten frequent diseases in terms of PubMed indexing and the citations of four Nobel prize winners. The relative impact factor (RIF) was calculated by medical specialty defined in Journal Citation Reports. The two queries, which included all the journals in category A (or A OR B), were added to any Medline/PubMed query as a central point of the feasibility study. Limitation using the SIGAPS category A was larger than the when using the Core Clinical Journals (CCJ): 15.65% of PubMed corpus vs 8.64% for CCJ. The response time of this limit applied to the entire PubMed corpus was less than two seconds. For five diseases out of ten, limiting the citations with the RIF was more effective than with the CCJ. For the four Nobel prize winners, limiting the citations with the RIF was more effective than the CCJ. The feasibility study to apply a new filter based on the relative impact factor on any Medline/PubMed query was positive. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  5. Predictive Indicators of Overuse Injuries in Adolescent Endurance Athletes.

    Science.gov (United States)

    Martínez-Silván, Daniel; Díaz-Ocejo, Jaime; Murray, Andrew

    2017-04-01

    To analyze the influence of training exposure and the utility of self-report questionnaires on predicting overuse injuries in adolescent endurance athletes. Five adolescent male endurance athletes (15.7 ± 1.4 y) from a full-time sports academy answered 2 questionnaires (Recovery Cue; RC-q and Oslo Sports Trauma Research questionnaire; OSTRC-q) on a weekly basis for 1 season (37 wk) to detect signs of overtraining and underrecovery (RC-q) and early symptoms of lower-limb injuries (OSTRC-q). All overuse injuries were retrospectively analyzed to detect which variations in the questionnaires in the weeks preceding injury were best associated. Overuse incidence rates were calculated based on training exposure. Lower-limb overuse injuries accounted for 73% of total injuries. The incidence rate for overuse training-related injuries was 10 injuries/1000 h. Strong correlations were observed between individual running exposure and overuse injury incidence (r(2) = .66), number of overuse injuries (r(2) = .69), and days lost (r(2) = .66). A change of 20% or more in the RC-q score in the preceding week was associated with 67% of the lower-limb overuse injuries. Musculoskeletal symptoms were only detected in advance by the OSTRC-q in 27% of the episodes. Training exposure (especially running exposure) was shown to be related to overuse injuries, suggesting that monitoring training load is a key factor for injury prevention. Worsening scores in the RC-q (but not the OSTRC) may be an indicator of overuse injury in adolescent endurance runners when used longitudinally.

  6. Factors that Limit and Enable Preschool-Aged Children's Physical Activity on Child Care Centre Playgrounds

    Science.gov (United States)

    Coleman, Bianca; Dyment, Janet E.

    2013-01-01

    The incidence of childhood obesity amongst preschool-aged children has increased dramatically in recent years and can be attributed, in part, to a lack of physical activity amongst children in this age group. This study explores the social factors that stand to limit and/or enable children's physical activity opportunities in outdoor settings…

  7. 23 CFR 636.302 - Are there any limitations on the selection and use of proposal evaluation factors?

    Science.gov (United States)

    2010-04-01

    ... TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS DESIGN-BUILD CONTRACTING Proposal Evaluation Factors § 636.302... contracting agency wishes to use Federal-aid highway funds for final design and construction, the subsequent... 23 Highways 1 2010-04-01 2010-04-01 false Are there any limitations on the selection and use...

  8. Physical limitations and fundamental factors affecting performance of liquid crystal tunable lenses with concentric electrode rings.

    Science.gov (United States)

    Li, Liwei; Bryant, Doug; van Heugten, Tony; Bos, Philip J

    2013-03-20

    A comprehensive analysis of fundamental factors and their effects on the performance of liquid crystal (LC)-based lenses is given. The analysis adopts numerical LC director and electric field simulation, as well as scalar diffraction theory for calculating the lens performance considering different variable factors. A high-efficiency LC lens with concentric electrode rings is fabricated for verifying and enriching the analysis. The measurement results are in close agreement with the analysis, and a summary of key factors is given with their quantitative contributions to the efficiency.

  9. Attaining higher resolution visual prosthetics: a review of the factors and limitations

    Science.gov (United States)

    Eiber, Calvin D.; Lovell, Nigel H.; Suaning, Gregg J.

    2013-02-01

    Visual prosthetics is an expanding subfield of functional electrical stimulation which has gained increased interest recently in light of new advances in treatments and technology. These treatments and technology represent a major improvement over prior art, but are still subject to a host of limitations which are dependent on the manner in which one approaches the topic of visual prosthetics. These limitations pose new research challenges whose solutions are directly applicable to the well-being of blind individuals everywhere. In this review, we will outline and critically compare major current approaches to visual prosthetics, and in particular retinal prosthetics. Then, we will engage in an in-depth discussion of the limitations imposed by current technology, physics, and the underlying biology of the retina to highlight several of the challenges currently facing researchers. .

  10. Voluntary stand-up physical activity enhances endurance exercise capacity in rats

    Science.gov (United States)

    Seo, Dae Yun; Lee, Sung Ryul; Kwak, Hyo-Bum; Seo, Kyo Won; McGregor, Robin A; Yeo, Ji Young; Ko, Tae Hee; Bolorerdene, Saranhuu; Kim, Nari; Ko, Kyung Soo; Rhee, Byoung Doo

    2016-01-01

    Involuntary physical activity induced by the avoidance of electrical shock leads to improved endurance exercise capacity in animals. However, it remains unknown whether voluntary stand-up physical activity (SPA) without forced simulating factors improves endurance exercise capacity in animals. We examined the eff ects of SPA on body weight, cardiac function, and endurance exercise capacity for 12 weeks. Twelve male Sprague-Dawley rats (aged 8 weeks, n=6 per group) were randomly assigned to a control group (CON) or a voluntary SPA group. The rats were induced to perform voluntary SPA (lifting a load equal to their body weight), while the food height (18.0 cm) in cages was increased progressively by 3.5 every 4 weeks until it reached 28.5 cm for 12 weeks. The SPA group showed a lower body weight compared to the CON group, but voluntary SPA did not affect the skeletal muscle and heart weights, food intake, and echocardiography results. Although the SPA group showed higher grip strength, running time, and distance compared to the CON group, the level of irisin, corticosterone, genetic expression of mitochondrial biogenesis, and nuclei numbers were not affected. These findings show that voluntary SPA without any forced stimuli in rats can eff ectively reduce body weight and enhance endurance exercise capacity, suggesting that it may be an important alternative strategy to enhance endurance exercise capacity. PMID:27162483

  11. Correlation between Quadriceps Endurance and Adduction Moment in Medial Knee Osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Soon-Hyuck Lee

    Full Text Available It is not clear whether the strength or endurance of thigh muscles (quadriceps and hamstring is positively or negatively correlated with the adduction moment of osteoarthritic knees. This study therefore assessed the relationships between the strength and endurance of the quadriceps and hamstring muscles and adduction moment in osteoarthritic knees and evaluated predictors of the adduction moment. The study cohort comprised 35 patients with unilateral medial osteoarthritis and varus deformity who were candidates for open wedge osteotomy. The maximal torque (60°/sec and total work (180°/sec of the quadriceps and hamstring muscles and knee adduction moment were evaluated using an isokinetic testing device and gait analysis system. The total work of the quadriceps (r = 0.429, P = 0.037 and hamstring (r = 0.426, P = 0.045 muscles at 180°/sec each correlated with knee adduction moment. Preoperative varus deformity was positively correlated with adduction moment (r = 0.421, P = 0.041. Multiple linear regression analysis showed that quadriceps endurance at 180°/sec was the only factor independently associated with adduction moment (β = 0.790, P = 0.032. The adduction moment of osteoarthritic knees correlated with the endurance, but not the strength, of the quadriceps muscle. However, knee adduction moment did not correlate with the strength or endurance of the hamstring muscle.

  12. Is back pain during childhood or adolescence associated with muscle strength, muscle endurance or aerobic capacity

    DEFF Research Database (Denmark)

    Lardon, Arnaud; Leboeuf-Yde, Charlotte; Le Scanff, Christine

    2015-01-01

    BACKGROUND: Back pain is a common condition during childhood and adolescence. The causes of back pain are largely unknown but it seems plausible that some physical factors such as back muscle strength, back muscle endurance and aerobic capacity may play a role in its development, in particular...... in the early years. OBJECTIVES: The objectives of this review were to investigate in childhood and adolescence 1) if muscular strength in trunk extension is associated with back pain, 2) if muscular endurance in trunk extension is associated with back pain and 3) if aerobic capacity is associated with back...

  13. Ensuring a Sustainable, Enduring Agriculture

    OpenAIRE

    Horne, James E.

    2010-01-01

    During the farm crisis of the 1980s we began to better understand the inherent faults of an industrialized food system. Despite large gains in productivity, efficiency, and economies of size, thousands of farms were in foreclosure. Many farmers were overly extended in debt. Others were in trouble because of a combination of factors such as drought, low crop prices, high input prices, and the lack of competition in the marketplace. The end result was the loss of thousands of farmers and a subs...

  14. Setting an indoor air exposure limit for formaldehyde: Factors of concern

    NARCIS (Netherlands)

    Arts, J.H.E.; Muijser, H.; Kuper, C.F.; Woutersen, R.A.

    2008-01-01

    The paper aims to evaluate the indoor air limit of 1 μg/m3 (0.8 ppb) formaldehyde as advised by the European Commission [the INDEX project; Kotzias, D., Koistinen, K., Kephalopoulos, S., Schlitt, C., Carrer, P., Maroni, M., Jantunen, M., Cochet, C., Kirchner, S., Lindvall, T., McLaughlin, J.,

  15. Setting an indoor air exposure limit for formaldehyde: Factors of concern

    NARCIS (Netherlands)

    Arts, J.H.E.; Muijser, H.; Kuper, C.F.; Woutersen, R.A.

    2008-01-01

    The paper aims to evaluate the indoor air limit of 1 μg/m3 (0.8 ppb) formaldehyde as advised by the European Commission [the INDEX project; Kotzias, D., Koistinen, K., Kephalopoulos, S., Schlitt, C., Carrer, P., Maroni, M., Jantunen, M., Cochet, C., Kirchner, S., Lindvall, T., McLaughlin, J., Mølhav

  16. Soil physical constraints as a limiting factor of palm and tree basal area in amazonian forests

    NARCIS (Netherlands)

    Emilio, T.; Quesada, C.A.; Costa, F.; Monteagudo, A.; Araujo, A.; Pena-Cruz, A.; Torres Lezama, A.; Castilho, C.V.; Neill, D.; Vilanova, E.; Oblitas Mendoza, E.M.; Alvarez, E.; Honorio, E.N.; Parada, G.A.; ter Steege, H.; Ramirez-Angulo, H.; Chave, J.; Terborgh, J.W.; Schietti, J.; Silveira, M.; Penuela-Mora, M.C.; Schwarz, M.; Banki, O.; Philips, O.L.; Thomas, R.; Vasquez, R.; Brienen, R.J.W.; Feldpausch, T.R.; Killeen, T.J.; Baker, T.R.; Magnusson, W.E.; Mahli, Y.

    2014-01-01

    Background: Trees and arborescent palms adopt different rooting strategies and responses to physical limitations imposed by soil structure, depth and anoxia. However, the implications of these differences for understanding variation in the relative abundance of these groups have not been explored.

  17. The Relationships Among Isokinetic Endurance, Initial Strength Level, and Fiber Type.

    Science.gov (United States)

    Clarkson, Priscilla M.; And Others

    1982-01-01

    Knee extension isokinetic peak torque was assessed at four angular velocities, and isokinetic endurance was assessed in eight college age men. Muscle fiber type was determined and related to isokinetic strength and fatigability. Results indicate that factors other than fiber type and initial strength level must influence the rate of isokinetic…

  18. Physics of Limiting Phenomena in Superconducting Microwave Resonators: Vortex Dissipation, Ultimate Quench and Quality Factor Degradation Mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Checchin, Mattia [IIT, Chicago

    2016-01-01

    Superconducting niobium accelerating cavities are devices operating in radio-frequency and able to accelerate charged particles up to energy of tera-electron-volts. Such accelerating structures are though limited in terms of quality factor and accelerating gradient, that translates--in some cases--in higher capital costs of construction and operation of superconducting rf accelerators. Looking forward for a new generation of more affordable accelerators, the physical description of limiting mechanisms in superconducting microwave resonators is discussed. In particular, the physics behind the dissipation introduced by vortices in the superconductor, the ultimate quench limitations and the quality factor degradation mechanism after a quench are described in detail. One of the limiting factor of the quality factor is the dissipation introduced by trapped magnetic flux vortices. The radio-frequency complex response of trapped vortices in superconductors is derived by solving the motion equation for a magnetic flux line, assuming a bi-dimensional and mean free path-dependent Lorentzian-shaped pinning potential. The resulting surface resistance shows the bell-shaped trend as a function of the mean free path, in agreement with the experimental data observed. Such bell-shaped trend of the surface resistance is described in terms of the interplay of the two limiting regimes identified as pinning and flux flow regimes, for low and large mean free path values respectively. The model predicts that the dissipation regime--pinning- or flux-flow-dominated--can be tuned either by acting on the frequency or on the electron mean free path value. The effect of different configurations of pinning sites and strength on the vortex surface resistance are also discussed. Accelerating cavities are also limited by the quench of the superconductive state, which limits the maximum accelerating gradient achievable. The accelerating field limiting factor is usually associate d to the

  19. Physics of Limiting Phenomena in Superconducting Microwave Resonators: Vortex Dissipation, Ultimate Quench and Quality Factor Degradation Mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Checchin, Mattia [Illinois Inst. of Technology, Chicago, IL (United States)

    2016-12-01

    Superconducting niobium accelerating cavities are devices operating in radio-frequency and able to accelerate charged particles up to energy of tera-electron-volts. Such accelerating structures are though limited in terms of quality factor and accelerating gradient, that translates--in some cases--in higher capital costs of construction and operation of superconducting rf accelerators. Looking forward for a new generation of more affordable accelerators, the physical description of limiting mechanisms in superconducting microwave resonators is discussed. In particular, the physics behind the dissipation introduced by vortices in the superconductor, the ultimate quench limitations and the quality factor degradation mechanism after a quench are described in detail. One of the limiting factor of the quality factor is the dissipation introduced by trapped magnetic flux vortices. The radio-frequency complex response of trapped vortices in superconductors is derived by solving the motion equation for a magnetic flux line, assuming a bi-dimensional and mean free path-dependent Lorentzian-shaped pinning potential. The resulting surface resistance shows the bell-shaped trend as a function of the mean free path, in agreement with the experimental data observed. Such bell-shaped trend of the surface resistance is described in terms of the interplay of the two limiting regimes identified as pinning and flux flow regimes, for low and large mean free path values respectively. The model predicts that the dissipation regime--pinning- or flux-flow-dominated--can be tuned either by acting on the frequency or on the electron mean free path value. The effect of different configurations of pinning sites and strength on the vortex surface resistance are also discussed. Accelerating cavities are also limited by the quench of the superconductive state, which limits the maximum accelerating gradient achievable. The accelerating field limiting factor is usually associate d to the

  20. CORRELATION BETWEEN BODY MASS INDEX AND HANDGRIP STRENGTH AND HANDGRIP ENDURANCE AMONG YOUNG HEALTHY ADULTS

    Directory of Open Access Journals (Sweden)

    Anupi

    2015-07-01

    Full Text Available BACKGROUND: Physical inactivity has become a serious problem all over the world. Handgrip Strength (a form of isometric static contraction test, is an important test to evaluate the physical fitness and nutritional status of an individua l. A number of factors like a ge, gender, body size, effort, skeletal muscle bulk and contractility may affect the handgrip strength (HGS and handgrip endurance (HGE. AIM: This study was conducted to establish the possible correlation (if any between body mass index and handgrip str ength and endurance among young healthy adults. MATERIALS AND METHODS: A population based cross - sectional study comprising of 200 students (both male and female, age group - 18 - 22 yrs was carried out in the Department of Physiology, Jorhat Medical College. Anthropometric parameters like height and weight were taken to evaluate the BMI and handgrip strength and handgrip endurance were taken by using handgrip dynamometer. According to WHO classification of BMI, subjects were categorized into three groups as un derweight BMI ≤18.5 kg/m 2 , normal weight BMI 18.5 - 24.9 kg/m 2 and overweight BMI≥ 24.9 kg/m 2 . Gender wise difference was analyzed by unpaired t test. Statistical analysis for correlation was done by using Karl Pearson’s Correlation Coefficient denoted by(r. RESULT: Males had higher handgrip strength and handgrip endurance than females. Statistic ally significant correlation was found between BMI and handgrip strength & endurance in underweight & overweight subjects. Gender differences in correlation were observed in correlation between BMI & HGS and HGE. CONCLUSION: The observed influence of BMI a nd gender differences in correlation between BMI and HGS and HGE indicate that besides BMI several other factors like effort, strength, muscular contractility etc . affect muscular strength & endurance in young males and females.

  1. Concurrent training in elite male runners: the influence of strength versus muscular endurance training on performance outcomes.

    Science.gov (United States)

    Sedano, Silvia; Marín, Pedro J; Cuadrado, Gonzalo; Redondo, Juan C

    2013-09-01

    Much recent attention has been given to the compatibility of combined aerobic and anaerobic training modalities. However, few of these studies have reported data related to well-trained runners, which is a potential limitation. Therefore, because of the limited evidence available for this population, the main aim was to determine which mode of concurrent strength-endurance training might be the most effective at improving running performance in highly trained runners. Eighteen well-trained male runners (age 23.7 ± 1.2 years) with a maximal oxygen consumption (VO2max) more than 65 ml·kg(-1)·min(-1) were randomly assigned into 1 of the 3 groups: Endurance-only Group (n = 6), who continued their usual training, which included general strength training with Thera-band latex-free exercise bands and endurance training; Strength Group (SG; n = 6) who performed combined resistance and plyometric exercises and endurance training; Endurance-SG (ESG; n = 6) who performed endurance-strength training with loads of 40% and endurance training. The study comprised 12 weeks of training in which runners trained 8 times a week (6 endurance and 2 strength sessions) and 5 weeks of detraining. The subjects were tested on 3 different occasions (countermovement jump height, hopping test average height, 1 repetition maximum, running economy (RE), VO2max, maximal heart rate [HRmax], peak velocity (PV), rating of perceived exertion, and 3-km time trial were measured). Findings revealed significant time × group interaction effects for almost all tests (p training for both SG and ESG groups led to improved maximal strength, RE, and PV with no significant effects on the VO2 kinetics pattern. The SG group also seems to show improvements in 3-km time trial tests.

  2. Plutonium in an enduring fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Pillay, K.K.S.

    1998-05-01

    Nuclear fuel cycles evolved over the past five decades have allowed many nations of the world to enjoy the benefits of nuclear energy, while contributing to the sustainable consumption of the world`s energy resources. The nuclear fuel cycle for energy production suffered many traumas since the 1970s because of perceived risks of proliferation of nuclear weapons. However, the experience of the past five decades has shown that the world community is committed to safeguarding all fissile materials and continuing the use of nuclear energy resources. Decisions of a few nations to discard spent nuclear fuels in geologic formations are contrary to the goals of an enduring nuclear fuel cycle and sustainable development being pursued by the world community. The maintenance of an enduring nuclear fuel cycle is dependent on sensible management of all the resources of the fuel cycle, including spent fuels.

  3. Climate factors play a limited role for past adaptation strategies in West Africa

    DEFF Research Database (Denmark)

    Mertz, Ole; Mbow, Cheikh; Nielsen, Jonas Østergaard;

    2010-01-01

    The Sudano-Sahelian zone of West Africa has experienced recurrent droughts since the mid-1970s and today there is considerable concern for how this region will be able to adapt to future climate change. To develop well targeted adaptation strategies, the relative importance of climate factors...... to be reflected in national adaptation strategies in the region....

  4. Bethe ansatz matrix elements as non-relativistic limits of form factors of quantum field theory

    NARCIS (Netherlands)

    Kormos, M.; Mussardo, G.; Pozsgay, B.

    2010-01-01

    We show that the matrix elements of integrable models computed by the algebraic Bethe ansatz (BA) can be put in direct correspondence with the form factors of integrable relativistic field theories. This happens when the S-matrix of a Bethe ansatz model can be regarded as a suitable non-relativistic

  5. Climate factors play a limited role for past adaptation strategies in West Africa

    DEFF Research Database (Denmark)

    Mertz, Ole; Mbow, Cheikh; Nielsen, Jonas Østergaard

    2010-01-01

    The Sudano-Sahelian zone of West Africa has experienced recurrent droughts since the mid-1970s and today there is considerable concern for how this region will be able to adapt to future climate change. To develop well targeted adaptation strategies, the relative importance of climate factors as ...

  6. Effect of elbow flexion, forearm rotation and upper arm abduction on MVC grip and grip endurance time.

    Science.gov (United States)

    Farooq, Mohd; Khan, Abid Ali

    2012-01-01

    This experiment was designed to know the effect of upper limb postural deviations on grip strength and grip endurance time. A full factorial design of experiment, i.e., 3 (0°, 45°, 90° abduction angles of upper arm) × 3 (45°, 90°, 135° angles of elbow flexion) × 3 (0°, -60° prone, +60° supine angles of forearm rotation) was used to find the effect of 27 combinations of postures on maximum voluntary contraction (MVC) grip strength and grip endurance time. The results showed that none of the main factors were significant on MVC grip, although there was a change in MVC grip. Grip endurance time significantly decreased with an increase in upper arm abduction. Also, grip endurance significantly increased with the elbow flexion angle and decreased with forearm rotation from neutral. These data will help designers and engineers to improve the workplace and tools to reduce the risk of injuries.

  7. Risky sexual behavior among rural female adolescents in Malaysia: a limited role of protective factors.

    Science.gov (United States)

    Ahmadian, Maryam; Hamsan, Hanina H; Abdullah, Haslinda; Samah, Asnarulkhadi Abu; Noor, Amna Md

    2014-03-23

    This paper presents the findings of a cross-sectional survey on the risk and protective factors of premarital sexual behavior among rural female adolescents in Peninsular Malaysia. We investigated data on 770 female respondents aged 13-17 years in rural areas to identify predictive factors for premarital sexual intercourse. Data were analyzed using bivariate and multivariate regression. Specific socio-demographic factors, psychological and family domains, peer delinquency, and knowledge and attitudes about sexuality were considered in risky sexual behaviors in rural Malay girls. The effects of other covariates for premarital sexual intercourse were controlled by logistic regression model. Of the 770 rural female students, about 3.2% of respondents reported experience of sexual intercourse in the past three months. Out of those sexually active girls, 36% were 17 years old and 20% stated having sexual intercourse with more than one partner, and 72% did not use contraception during the most recent sexual intercourse. Midnight activities, peer-sexual disorder, self-evaluation, and attitude toward sexual health were significant predictors of sexual intercourse in rural girls in Malaysia. The finding highlights the impact of psychological factors and peer group influences on the challenges of premarital sexual behavior among rural girls and the notion of school-based sexual health education for adolescents. This study triggers other researchers take into account a comprehensive view of protective factors operating in adolescents' risky sexual behaviors in Asian culture seeing that family domain variables, unexpectedly, exerted no predicting influence on sexually active female teens in rural areas in Malaysia.

  8. Pigment epithelium-derived factor (PEDF): a novel trophoblast-derived factor limiting feto-placental angiogenesis in late pregnancy.

    Science.gov (United States)

    Loegl, Jelena; Nussbaumer, Erika; Hiden, Ursula; Majali-Martinez, Alejandro; Ghaffari-Tabrizi-Wizy, Nassim; Cvitic, Silvija; Lang, Ingrid; Desoye, Gernot; Huppertz, Berthold

    2016-07-01

    The rapidly expanding feto-placental vasculature needs tight control by paracrine and endocrine mechanisms. Here, we focused on paracrine influence by trophoblast, the placental epithelium. We aimed to identify differences in regulation of feto-placental angiogenesis in early versus late pregnancy. To this end, the effect of conditioned media (CM) from early and late pregnancy human trophoblast was tested on network formation, migration and proliferation of human feto-placental endothelial cells. Only CM of late pregnancy trophoblast reduced network formation and migration. Screening of trophoblast transcriptome for anti-angiogenic candidates identified pigment epithelium-derived factor (PEDF) with higher expression and protein secretion in late pregnancy trophoblast. Addition of a PEDF-neutralizing antibody restored the anti-angiogenic effect of CM from late pregnancy trophoblast. Notably, human recombinant PEDF reduced network formation only in combination with VEGF. Also in the CAM assay, the combination of PEDF with VEGF reduced branching of vessels below control levels. Analysis of phosphorylation of ERK1/2 and FAK, two key players in VEGF-induced proliferation and migration, revealed that PEDF altered VEGF signaling, while PEDF alone did not affect phosphorylation of ERK1/2 and FAK. These data suggest that the trophoblast-derived anti-angiogenic molecule PEDF is involved in restricting growth and expansion of the feto-placental endothelium predominantly in late pregnancy and targets to modulate the intracellular effect of VEGF.

  9. Antarctic crabs: invasion or endurance?

    Science.gov (United States)

    Griffiths, Huw J; Whittle, Rowan J; Roberts, Stephen J; Belchier, Mark; Linse, Katrin

    2013-01-01

    Recent scientific interest following the "discovery" of lithodid crabs around Antarctica has centred on a hypothesis that these crabs might be poised to invade the Antarctic shelf if the recent warming trend continues, potentially decimating its native fauna. This "invasion hypothesis" suggests that decapod crabs were driven out of Antarctica 40-15 million years ago and are only now returning as "warm" enough habitats become available. The hypothesis is based on a geographically and spatially poor fossil record of a different group of crabs (Brachyura), and examination of relatively few Recent lithodid samples from the Antarctic slope. In this paper, we examine the existing lithodid fossil record and present the distribution and biogeographic patterns derived from over 16,000 records of Recent Southern Hemisphere crabs and lobsters. Globally, the lithodid fossil record consists of only two known specimens, neither of which comes from the Antarctic. Recent records show that 22 species of crabs and lobsters have been reported from the Southern Ocean, with 12 species found south of 60 °S. All are restricted to waters warmer than 0 °C, with their Antarctic distribution limited to the areas of seafloor dominated by Circumpolar Deep Water (CDW). Currently, CDW extends further and shallower onto the West Antarctic shelf than the known distribution ranges of most lithodid species examined. Geological evidence suggests that West Antarctic shelf could have been available for colonisation during the last 9,000 years. Distribution patterns, species richness, and levels of endemism all suggest that, rather than becoming extinct and recently re-invading from outside Antarctica, the lithodid crabs have likely persisted, and even radiated, on or near to Antarctic slope. We conclude there is no evidence for a modern-day "crab invasion". We recommend a repeated targeted lithodid sampling program along the West Antarctic shelf to fully test the validity of the "invasion hypothesis".

  10. Frequency of classic stereotypies in endurance horses

    Directory of Open Access Journals (Sweden)

    Lisandro E. Muñoz-Alonzo

    2015-06-01

    Full Text Available The objective of this study was to determine the frequency of classic stereotypies in endurance horses of Región Metropolitana (Chile and the association of these abnormal behaviors with age and sex of the animals. All resident endurance horses from 8 equestrian centres of the Región Metropolitana were studied (n=107. A description of classic stereotipies (crib-biting, weaving and box-walking was given to each horse keeper and then they were asked for this presence or absence, along the name, sex, age and breed, of every horse under their care. To analyze the data, horses were divided by age into 3 groups: 3 to 6 years (n=28, 7 to 9 years (n=42 and 10 to 18 years (n=37. Based on their sex, they were divided into 3 groups: stallions (n =11, geldings (n=64 and mares (n=32. Results are expressed as percentages. Fisher`s test with p < 0.05 was used for statistical analysis of the variables age and sex. A 12.2% of all horses presented stereotypies: crib -biting (0.9%, weaving (6.5% and box-walking (4.7%. No relationship was found between the presence of stereotypies and variables age and sex. This study evidence a high frequency of classic stereotypies in endurance horses of Región Metropolitana, mostly weaving, and no found association between classic stereotypies and the variables age and sex of horses.

  11. Triacilglicerol intramuscular: um importante substrato energético para o exercício de endurance Triacilglicerol intramuscular: un importante substrato energético para el ejercicio de endurance Intramuscular triacylglycerol: an important energetic substrate for endurance exercise

    Directory of Open Access Journals (Sweden)

    Mônica Aparecida Belmonte

    2005-04-01

    on the actual relative participation of this fuel during endurance exercise. The apparent discrepancy in literature is associated to methodological limitations that have been associated with the strategies used to estimate its oxidation during exercise. In order to deplete this issue, more research using new methods (e.g., utilization of stable isotope methodology, magnetic resonance spectroscopy, and electron microscopy should be conducted.

  12. Strength Training Prior to Endurance Exercise: Impact on the Neuromuscular System, Endurance Performance and Cardiorespiratory Responses

    Directory of Open Access Journals (Sweden)

    Conceição Matheus

    2014-12-01

    Full Text Available This study aimed to investigate the acute effects of two strength-training protocols on the neuromuscular and cardiorespiratory responses during endurance exercise. Thirteen young males (23.2 ± 1.6 years old participated in this study. The hypertrophic strength-training protocol was composed of 6 sets of 8 squats at 75% of maximal dynamic strength. The plyometric strength-training protocol was composed of 6 sets of 8 jumps performed with the body weight as the workload. Endurance exercise was performed on a cycle ergometer at a power corresponding to the second ventilatory threshold until exhaustion. Before and after each protocol, a maximal voluntary contraction was performed, and the rate of force development and electromyographic parameters were assessed. After the hypertrophic strengthtraining and plyometric strength-training protocol, significant decreases were observed in the maximal voluntary contraction and rate of force development, whereas no changes were observed in the electromyographic parameters. Oxygen uptake and a heart rate during endurance exercise were not significantly different among the protocols. However, the time-to-exhaustion was significantly higher during endurance exercise alone than when performed after hypertrophic strength-training or plyometric strength-training (p <0.05. These results suggest that endurance performance may be impaired when preceded by strength-training, with no oxygen uptake or heart rate changes during the exercise.

  13. TRAINABILITY OF BODY COMPOSITION, AEROBIC POWER AND MUSCULAR ENDURANCE OF CADET WRESTLERS

    Directory of Open Access Journals (Sweden)

    Bahman Mirzaei

    2016-10-01

    Full Text Available Purpose: The purpose of the present study was to investigate the trainability of body composition, aerobic power and muscular endurance of cadet wrestlers. Material: Fifteen cadet wrestlers (age: 15.20±0.94 years participated in this study. Methods: The testing was conducted twice, before and after four-week training period. The physiological parameters included aerobic power, muscular endurance and body composition. Results: A significant decrease in the body fat was observed following the training (p0.05. In general, although a lot of factors including skill, mental, genetic and other fitness factors render some influences on a wrestler's success, improvement of physical fitness plays an important role in championship. Based on results of the present study more time is needed to improve muscular and cardiovascular endurance, therefore wrestling coaches and trainers are recommended to pay special attention to these factors. Conclusion: Our results indicated that wrestlers experienced significant changes in their body fat percentage during four-week training period. Cadet wrestlers’ aerobic power, muscular endurance and body composition are trainable, although these improvements may be less than what has been observed in junior and senior wrestlers.

  14. Covariant quark model of form factors in the heavy mass limit

    OpenAIRE

    Yaouanc, A. Le; Oliver, L; Pène, O.; Raynal, J. -C.

    1995-01-01

    We show that quark models of current matrix-elements based on the Bakamjian-Thomas construction of relativistic states with a fixed number of particles, plus the additivity assumption, are covariant in the heavy-quark limit and satisfy the full set of heavy-quark symmetry relations discovered by Isgur and Wise. We find the lower bound of $\\rho^2$ in such models to be $3/4$ for ground state mesons, independently of any parameter. Another welcome property of these models is that in the infinite...

  15. Theory of factors limiting high gradient operation of warm accelerating structures

    Energy Technology Data Exchange (ETDEWEB)

    Nusinovich, Gregory S. [Univ. of Maryland, College Park, MD (United States)

    2014-07-22

    This report consists of two parts. In the first part we describe a study of the heating of microprotrusions on surfaces of accelerating structures. This ;process is believed to lead to breakdown in these structures. Our study revealed that for current accelerator parameters melting should not occur due to space charge limitations of the current emitted by a protrusion. The second part describes a novel concept to develop THz range sources based on harmonic cyclotron masers for driving future colliders. This work was stimulated by a recent request of SLAC to develop high power, high-efficiency sources of sub-THz radiation for future high-gradient accelerators.

  16. On limitation of quality factor of single mode resonators with finite size

    CERN Document Server

    Ferdous, Fahmida; Vyatchanin, Sergey P; Matsko, Andrey B; Maleki, Lute

    2014-01-01

    Using realistic numerical models we analyze radiative loss of bound and unbound modes of specially designed high-Q whispering gallery and Fabry-Perot cavities of similar size and shape, and find a set of parameters when they can be treated as single mode structures. We show that these cavities have similar properties in spite of their different loss mechanisms. The cavity morphology engineering does not lead to reduction of the resonator quality factor.

  17. Autonomous Soaring for Improved Endurance of a Small Uninhabited Air Vehicle

    Science.gov (United States)

    Allen, Michael J.

    2005-01-01

    A relatively unexplored method to improve the endurance of an autonomous aircraft is to use buoyant plumes of air found in the lower atmosphere called thermals or updrafts. Glider pilots and birds commonly use updrafts to improve range, endurance, or cross-country speed. This report presents a quantitative analysis of a small electric-powered uninhabited air vehicle using updrafts to extend its endurance over a target location. A three-degree-of-freedom simulation of the uninhabited air vehicle was used to determine the yearly effect of updrafts on performance. Surface radiation and rawinsonde balloon measurements taken at Desert Rock, Nevada, were used to determine updraft size, strength, spacing, shape, and maximum height for the simulation. A fixed-width spiral path was used to search for updrafts at the same time as maintaining line-of-sight to the surface target position. Power was used only when the aircraft was flying at the lower-altitude limit in search of updrafts. Results show that an uninhabited air vehicle with a nominal endurance of 2 hours can fly a maximum of 14 hours using updrafts during the summer and a maximum of 8 hours during the winter. The performance benefit and the chance of finding updrafts both depend on what time of day the uninhabited air vehicle is launched. Good endurance and probability of finding updrafts during the year was obtained when the uninhabited air vehicle was launched 30 percent into the daylight hours after sunrise each day. Yearly average endurance was found to be 8.6 hours with these launch times.

  18. Continuum limit of the leading order HQET form factor in B{sub s}→Klν decays

    Energy Technology Data Exchange (ETDEWEB)

    Bahr, Felix; Banerjee, Debasish; Koren, Mateusz; Simma, Hubert; Sommer, Rainer [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Bernardoni, Fabio [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Technische Univ. Dresden (Germany). Medizinische Fakultaet ' ' Carl Gustav Carus' ' ; Joseph, Anosh [Cambridge Univ. (United Kingdom). Dept. of Applied Mathematics and Theoretical Physics (DAMTP); Collaboration: ALPHA Collaboration

    2016-01-15

    We discuss the computation of form factors for semi-leptonic decays of B-, B{sub s}- mesons in lattice QCD. Considering in particular the example of the static B{sub s} form factors we demonstrate that after non-perturbative renormalization the continuum limit can be taken with confidence. The resulting precision is of interest for extractions of V{sub ub}. The size of the corrections of order 1/m{sub b} is just estimated at present but it is expected that their inclusion does not pose significant difficulties.

  19. Endurance Times of the Thoracolumbar Musculature: Reference Values for Female Recreational Resistance Training Participants.

    Science.gov (United States)

    Hanney, William J; Kolber, Morey J; Pabian, Patrick S; Cheatham, Scott W; Schoenfeld, Brad J; Salamh, Paul A

    2016-02-01

    The assessment of thoracolumbar muscle endurance (TLME) is common among strength and conditioning professionals and clinicians desiring to quantify baseline muscle performance and determine injury risk. Reference values for such assessments are documented in the literature; however, their utility may be of limited value due to heterogeneous participant selection and limited demographic reporting. Moreover, active cohorts who engage in resistance training (RT) may reach a ceiling effect on existing reference values when testing routinely trained muscles. Thus, the purpose of this study was to establish reference values for standardized TLME tests among women who participate in recreational RT and to determine whether imbalances or asymmetries exist. Participants included 61 women aged 18-59 years who engaged in RT for at least 1 year. Flexor, extensor, and lateral flexor TLME was isometrically assessed using standardized procedures with documented reproducibility (r ≥ 0.93). Results identified significant differences (p values, suggesting a training effect or bias. Moreover, similar imbalances favoring the flexors are a documented risk factor for low back pain. Thus, training considerations inclusive of the extensors may benefit women who engage in RT as a means of mitigating risk. Individuals evaluating muscle performance should consider reference values that represent the population of interest.

  20. Explosive limits and its container factors of polybasic explosive mixture gas containing H2, CH4 and CO

    Institute of Scientific and Technical Information of China (English)

    胡耀元; 李勇; 朱凯汉; 周邦智; 杨元法

    2002-01-01

    Explosive characteristics of polybasic explosive mixture gas are systematically researched. Over 28000 experimental data have been obtained from 1278 effective experiments. The paper probes into the concentration explosive limits and the container factors of polybasic explosive mixture gas which contains H2, CH4 and CO. It has worked out the sufficient and necessary condition for branch-chain explosion and the unified expression of the probability of the heterogeneous chain termination. Experiments indicate that the concentration explosive limits of polybasic explosive mixture gas (H2, CH4, CO) relate to many factors. They enlarge with the augmentability of the container (linear size, geometric shape, and flame spread direction). This will be of great significance to guiding the revision of related industrial safety targets, reclaiming and reusing related industrial tail gas and waste gas, taking precautions against the explosion hazard of mixture gas in correlated industry and mines, and applying the br

  1. Hilbert-space factorization is a limited and expensive information-processing resource

    CERN Document Server

    Fields, Chris

    2014-01-01

    By taking the need for quantum reference frames into account, it is shown that Hilbert-space factorization is a dissipative process requiring on the order of kT to reduce by one bit an observer's uncertainty in the provenance of a classically-recorded observational outcome. This cost is neglected in standard treatments of decoherence that assume that observational outcomes are obtained by interacting with a collection of degrees of freedom identified a priori. Treating this cost explicitly leads to a natural measure of the probability of any particular quantum reference frame.

  2. EXAMINATION OF SILICATE LIMITATION OF PRIMARY PRODUCTION IN JIAOZHOU BAY, CHINA Ⅰ. SILICATE BEING A LIMITING FACTOR OF PHYTOPLANKTON PRIMARY PRODUCTION

    Institute of Scientific and Technical Information of China (English)

    杨东方; 张经; 吕吉斌; 高振会; 陈豫

    2002-01-01

    Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou B ay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO-3-N, NO-2-N, NH+4-N, SiO2-3-Si, PO3-4-P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq.(1) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temp erature; that the main factor controlling the primary production is Si; that water temper ature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecologica l niches for C, the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D, the coefficient of water temperature's effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay , the biogeochemical sediment process of the silicon, the phytoplankton predominan t species and the phytoplankton structure. The authors considered silicate a limit ing factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and up take by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrins ic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant

  3. EXAMINATION OF SILICATE LIMITATION OF PRIMARY PRODUCTION IN JIAOZHOU BAY, CHINA——I. SILICATE BEING A LIMITING FACTOR OF PHYTOPLANKTON PRIMARY PRODUCTION

    Institute of Scientific and Technical Information of China (English)

    杨东方; 张经; 吕吉斌; 高振会; 陈豫

    2002-01-01

    Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO3--N, NO2--N, NH4+-N, SIO32--Si, PO43--P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq. ( 1 ) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temperature; that the main factor controlling the primary production is Si; that water temperature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecological niches for C, the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D, the coefficient of water temperature's effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay, the biogeochemical sediment process of the silicon, the phytoplankton predominant species and the phytoplankton structure. The authors considered silicate a limiting factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and uptake by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrinsic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant

  4. Translocation of Neurospora crassa transcription factor NUC-1 into the nucleus is induced by phosphorus limitation.

    Science.gov (United States)

    Peleg, Y; Addison, R; Aramayo, R; Metzenberg, R L

    1996-09-01

    NUC-1, a basic helix-loop-helix zipper protein, activates the expression of several genes involved in phosphorus acquisition in Neurospora crassa. In the present study we investigated whether posttranscriptional mechanisms control the activity of NUC-1. The NUC-1 level was higher (up to fivefold) in wild-type cells grown at low external phosphate concentration and in mutant strains expressing the phosphorus acquisition genes constitutively than in a wild-type strain grown at high external phosphate concentration. Using indirect immunofluorescence we demonstrated that NUC-1 is localized at least predominantly in the cytosol when wild-type N. crassa is grown with an adequate supply of phosphate, whereas NUC-1 is largely concentrated in the nucleus upon limitation of external phosphate. In mutant strains expressing the phosphorus acquisition genes constitutively, NUC-1 localization was also primarily in the nucleus. Thus, subcellular compartmentation of regulatory proteins is an important mechanism in regulating gene expression in filamentous fungi.

  5. Airflow limitation as a risk factor for low bone mineral density and hip fracture

    Science.gov (United States)

    Herland, Trine; Apalset, Ellen M; Eide, Geir Egil; Tell, Grethe S; Lehmann, Sverre

    2016-01-01

    Aim To investigate whether airflow limitation is associated with bone mineral density (BMD) and risk of hip fractures. Methods A community sample of 5,100 subjects 47–48 and 71–73 years old and living in Bergen was invited. Participants filled in questionnaires and performed a post-bronchodilator spirometry measuring forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC). All attendants were invited to have a BMD measurement of the hip. During 10 years of follow-up, information on death was collected from the Norwegian Cause of Death Registry, and incident hip fractures were registered from regional hospital records of discharge diagnoses and surgical procedure codes. Results The attendance rate was 69% (n=3,506). The prevalence of chronic obstructive pulmonary disease (COPD) (FEV1/FVC<0.7) was 9%. In multiple logistic regression, the lowest quartile of BMD versus the three upper was significantly predicted by FEV1/FVC<0.7 and FEV1% predicted (odds ratio [OR]: 1.58, 95% confidence interval [CI]: 1.11 to 2.25, and OR per increase of 10%: 0.92, 95% CI: 0.86 to 0.99, respectively). Hip fracture occurred in 126 (4%) participants. In a Cox regression analysis, FEV1% predicted was associated with a lowered risk of hip fracture (hazard ratio per increase of 10%: 0.89, 95% CI: 0.79 to 0.997). Conclusion Airflow limitation is positively associated with low BMD and risk of hip fracture in middle-aged and elderly. PMID:27733234

  6. Static and Dynamic Handgrip Strength Endurance: Test-Retest Reproducibility.

    Science.gov (United States)

    Gerodimos, Vassilis; Karatrantou, Konstantina; Psychou, Dimitra; Vasilopoulou, Theodora; Zafeiridis, Andreas

    2017-03-01

    This study investigated the reliability of static and dynamic handgrip strength endurance using different protocols and indicators for the assessment of strength endurance. Forty young, healthy men and women (age, 18-22 years) performed 2 handgrip strength endurance protocols: a static protocol (sustained submaximal contraction at 50% of maximal voluntary contraction) and a dynamic one (8, 10, and 12 maximal repetitions). The participants executed each protocol twice to assess the test-retest reproducibility. Total work and total time were used as indicators of strength endurance in the static protocol; the strength recorded at each maximal repetition, the percentage change, and fatigue index were used as indicators of strength endurance in the dynamic protocol. The static protocol showed high reliability irrespective of sex and hand for total time and work. The 12-repetition dynamic protocol exhibited moderate-high reliability for repeated maximal repetitions and percentage change; the 8- and 10-repetition protocols demonstrated lower reliability irrespective of sex and hand. The fatigue index was not a reliable indicator for the assessment of dynamic handgrip endurance. Static handgrip endurance can be measured reliably using the total time and total work as indicators of strength endurance. For the evaluation of dynamic handgrip endurance, the 12-repetition protocol is recommended, using the repeated maximal repetitions and percentage change as indicators of strength endurance. Practitioners should consider the static (50% maximal voluntary contraction) and dynamic (12 repeated maximal repetitions) protocols as reliable for the assessment of handgrip strength endurance. The evaluation of static endurance in conjunction with dynamic endurance would provide more complete information about hand function. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  7. Seasonal shift in climatic limiting factors on tree transpiration: evidence from sap flow observations at alpine treelines in southeast Tibet

    Directory of Open Access Journals (Sweden)

    Liu Xinsheng

    2016-07-01

    Full Text Available Alpine and northern treelines are primarily controlled by low temperatures. However, little is known about the impact of low soil temperature on tree transpiration at treelines. We aim to test the hypothesis that in cold-limited forests, the main limiting factors for tree transpiration switch from low soil temperature before summer solstice to atmospheric evaporative demand after summer solstice, which generally results in low transpiration in the early growing season. Sap flow, meteorological factors and predawn needle water potential were continuously monitored throughout one growing season across Smith fir (Abies georgei var. smithii and juniper (Juniperus saltuaria treelines in southeast Tibet. Sap flow started in early May and corresponded to a threshold mean air-temperature of 0 oC. Across tree species, transpiration was mainly limited by low soil temperature prior to the summer solstice but by vapor pressure deficit and solar radiation post-summer solstice, which was further confirmed on a daily scale. As a result, tree transpiration for both tree species was significantly reduced in the pre-summer solstice period as compared to post-summer solstice, resulting in a lower predawn needle water potential for Smith fir trees in the early growing season. Our data supported the hypothesis, suggesting that tree transpiration mainly responds to soil temperature variations in the early growing season. The results are important for understanding the hydrological response of cold-limited forest ecosystems to climate change.

  8. Seasonal Shift in Climatic Limiting Factors on Tree Transpiration: Evidence from Sap Flow Observations at Alpine Treelines in Southeast Tibet.

    Science.gov (United States)

    Liu, Xinsheng; Nie, Yuqin; Luo, Tianxiang; Yu, Jiehui; Shen, Wei; Zhang, Lin

    2016-01-01

    Alpine and northern treelines are primarily controlled by low temperatures. However, little is known about the impact of low soil temperature on tree transpiration at treelines. We aim to test the hypothesis that in cold-limited forests, the main limiting factors for tree transpiration switch from low soil temperature before summer solstice to atmospheric evaporative demand after summer solstice, which generally results in low transpiration in the early growing season. Sap flow, meteorological factors and predawn needle water potential were continuously monitored throughout one growing season across Smith fir (Abies georgei var. smithii) and juniper (Juniperus saltuaria) treelines in southeast Tibet. Sap flow started in early May and corresponded to a threshold mean air-temperature of 0°C. Across tree species, transpiration was mainly limited by low soil temperature prior to the summer solstice but by vapor pressure deficit and solar radiation post-summer solstice, which was further confirmed on a daily scale. As a result, tree transpiration for both tree species was significantly reduced in the pre-summer solstice period as compared to post-summer solstice, resulting in a lower predawn needle water potential for Smith fir trees in the early growing season. Our data supported the hypothesis, suggesting that tree transpiration mainly responds to soil temperature variations in the early growing season. The results are important for understanding the hydrological response of cold-limited forest ecosystems to climate change.

  9. Endogenous tissue factor pathway inhibitor has a limited effect on host defence in murine pneumococcal pneumonia.

    Science.gov (United States)

    van den Boogaard, Florry E; van 't Veer, Cornelis; Roelofs, Joris J T H; Meijers, Joost C M; Schultz, Marcus J; Broze, George J; van der Poll, Tom

    2015-07-01

    Streptococcus (S.) pneumoniae is the most common causative pathogen in community-acquired pneumonia. Coagulation and inflammation interact in the host response to infection. Tissue factor pathway inhibitor (TFPI) is a natural anticoagulant protein that inhibits tissue factor (TF), the main activator of inflammation-induced coagulation. It was the objective of this study to investigate the effect of endogenous TFPI levels on coagulation, inflammation and bacterial growth during S. pneumoniae pneumonia in mice. The effect of low endogenous TFPI levels was studied by administration of a neutralising anti-TFPI antibody to wild-type mice, and by using genetically modified mice expressing low levels of TFPI, due to a genetic deletion of the first Kunitz domain of TFPI (TFPIK1(-/-)) rescued with a human TFPI transgene. Pneumonia was induced by intranasal inoculation with S. pneumoniae and samples were obtained at 6, 24 and 48 hours after infection. Anti-TFPI reduced TFPI activity by ~50 %. Homozygous lowTFPI mice and heterozygous controls had ~10 % and ~50 % of normal TFPI activity, respectively. TFPI levels did not influence bacterial growth or dissemination. Whereas lung pathology was unaffected in all groups, mice with ~10 % (but not with ~50 %) of TFPI levels displayed elevated lung cytokine and chemokine concentrations 24 hours after infection. None of the groups with low TFPI levels showed an altered procoagulant response in lungs or plasma during pneumonia. These data argue against an important role for endogenous TFPI in the antibacterial, inflammatory and procoagulant response during pneumococcal pneumonia.

  10. Sociological Factors and Structural Limitations on College Students' Participation in Recreational Activities

    Directory of Open Access Journals (Sweden)

    Metin KILIÇ

    2013-12-01

    Full Text Available Socio-cultural factors are said to exist on the basis of the participating in the recreational activities. In today's complex social structure, institutionally, individuals' recreational activities have become a problematic issue. Thus, it is thought to be vital that studies must be done in order to create spaces for recreational activities for the integration of young people with the existing social structure and increase the participation level to these activities. This research was carried out on the students who studied in different faculties of Adiyaman University in 2012-2013. The sample of research was determined according to random sampling technique, compliant with the criteria's of the level of representing the population. The study is a descriptive field research in which 391 questionnaires were conducted. As a result of the research it was determined that the college students' recreation opportunities, which are factors in the process of socializing and effect their personalities, are inadequate. Besides, striking results were gained regarding their expectations from university.

  11. The effect of interference of endurance and concurrent (endurance-resistance training programs on femoral bone mineral density and mechanical strength of osteoporotic male rats

    Directory of Open Access Journals (Sweden)

    F nazem

    2016-01-01

    exercise intervention resulted in a significant increase in maximum force (p=0.001 and stiffness (p=0.027 without statistical significance differences in BMD (p=0.514. Incremental changes in factors of BMD (p=0.000, maximum force (p=0.000 and stiffness (p=0.006 of femoral Concurrent training group obtained more than endurance training group. Conclusion: The results of this study showed that the combination of endurance and strength training exercise may have a synergistic effect on increasing the mechanical strength of osteoporotic femoral bone in male rats versus to endurance training alone.

  12. Subclinical Theileria Equi Infection and Rhabdomyolysis in Three Endurance Horses

    Directory of Open Access Journals (Sweden)

    A. Muñoz1,2*, R. G. M. Rodríguez2, C. Riber1,2, P. Trigo2, M. Gómez-Díez2 and F. Castejon2

    2013-04-01

    Full Text Available Three well-trained endurance horses, competing over different distances, developed sudden and unexpected rhabdomyolysis at the onset of exercise. They were treated and afterwards they did not have any other bout of muscle damage. All of them were positive to Theileria equi (polymerase reaction chain. The possible reasons of the rhabdomyolysis could have been the direct effect of the parasite on the muscle and/or the result of the anemia and a limited oxygen supply to the exercising muscles. It is suggested that the horses were carriers of Theileria and they developed clinical signs because of the immune-suppression caused by prolonged submaximal exercise and/or transportation.

  13. Estimating seismic demand parameters using the endurance time method

    Institute of Scientific and Technical Information of China (English)

    Ramin MADARSHAHIAN; Homayoon ESTEKANCHI; Akbar MAHVASHMOHAMMADI

    2011-01-01

    The endurance time (ET) method is a time history based dynamic analysis in which structures are subjected to gradually intensifying excitations and their performances are judged based on their responses at various excitation levels.Using this method,the computational effort required for estimating probable seismic demand parameters can be reduced by an order of magnitude.Calculation of the maximum displacement or target displacement is a basic requirement for estimating performance based on structural design.The purpose of this paper is to compare the results of the nonlinear ET method with the nonlinear static pushover (NSP) method of FEMA 356 by evaluating performances and target displacements of steel frames.This study will lead to a deeper insight into the capabilities and limitations of the ET method.The results are further compared with those of the standard nonlinear response history analysis.We conclude that results from the ET analysis are in proper agreement with those from standard procedures.

  14. Results of a 1462 hour ammonia arcjet endurance test

    Science.gov (United States)

    Polk, J. E.; Goodfellow, K. D.

    1992-07-01

    A total of 1462 hours of operaton were demonstrated in an endurance test of a 30 kWe-class ammonia arcjet operated at 10 kWe. The propellant flow rate was 0.170 g/s, and the measured performance increased from approximately 650 s specific impulse at 36 percent efficiency at the beginning of the test to 675 s at 39 percent near the end. The voltage increased and the current dropped slightly over the first 400 hours, and then remained approximately constant for the remainder of the test. The test, scheduled for 1500 hours, was terminated after an insulator in the rear of the engine failed. Post-test examination of the electrodes revealed only minimal damage. Although there was evidence of a number of mass transport processes occurring in the discharge chamber, the primary life-limiting wear mechanisms appear to be cathode tip erosion and constrictor melting.

  15. A measurement of the QCD colour factors and a limit on the light gluino

    CERN Document Server

    Barate, R; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Odier, P; Pietrzyk, B; Casado, M P; Chmeissani, M; Comas, P; Crespo, J M; Delfino, M C; Fernández, E; Fernández-Bosman, M; Garrido, L; Juste, A; Martínez, M; Miquel, R; Mir, L M; Orteu, S; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Alemany, R; Bazarko, A O; Bright-Thomas, P G; Cattaneo, M; Cerutti, F; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Mato, P; Minten, Adolf G; Moneta, L; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rizzo, G; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, E; Thomson, F; Turnbull, R M; Becker, U; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Schmidt, M; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Martin, E B; Moutoussi, A; Nash, J; Sedgbeer, J K; Stacey, A M; Williams, M D; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Williams, M I; Galla, A; Giehl, I; Greene, A M; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Coyle, P; Diaconu, C A; Etienne, F; Konstantinidis, N P; Leroy, O; Payre, P; Rousseau, D; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Ragusa, F; Berlich, R; Blum, Walter; Büscher, V; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Chen, S; Choi, Y; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, A; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Park, H J; Schune, M H; Simion, S; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Venturi, A; Verdini, P G; Blair, G A; Bryant, L M; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Kelly, M S; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Grupen, Claus; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Greening, T C; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, J; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1997-01-01

    Using data collected from 1992 to 1995 with the ALEPH detector at LEP, a measurement of the colour factor ratios CA/CF and TF/CF and the strong coupling constant $\\overline{\\alpha}_s = CF \\alpha_s(Mz)/ (2\\pi)$ has been performed by fitting theoretical predictions simultaneously to the measured differential two-jet rate and angular distributions in four-jet events. The result is found to be in excellent agreement with QCD, CA/CF = 2.20 +- 0.09 (stat) +- 0.13 (syst) , TF/CF = 0.29 +- 0.05 (stat) +- 0.06 (syst) . Fixing CA/CF$ and TF/CF to the QCD values permits a determination of $\\alpha_s(Mz)$ and nf, the number of active flavours. With this measurement the existence of a gluino with mass below 6.3 GeV/c^2 is excluded at 95% confidence level.

  16. Systematic repression of transcription factors reveals limited patterns of gene expression changes in ES cells

    Science.gov (United States)

    Nishiyama, Akira; Sharov, Alexei A.; Piao, Yulan; Amano, Misa; Amano, Tomokazu; Hoang, Hien G.; Binder, Bernard Y.; Tapnio, Richard; Bassey, Uwem; Malinou, Justin N.; Correa-Cerro, Lina S.; Yu, Hong; Xin, Li; Meyers, Emily; Zalzman, Michal; Nakatake, Yuhki; Stagg, Carole; Sharova, Lioudmila; Qian, Yong; Dudekula, Dawood; Sheer, Sarah; Cadet, Jean S.; Hirata, Tetsuya; Yang, Hsih-Te; Goldberg, Ilya; Evans, Michele K.; Longo, Dan L.; Schlessinger, David; Ko, Minoru S. H.

    2013-01-01

    Networks of transcription factors (TFs) are thought to determine and maintain the identity of cells. Here we systematically repressed each of 100 TFs with shRNA and carried out global gene expression profiling in mouse embryonic stem (ES) cells. Unexpectedly, only the repression of a handful of TFs significantly affected transcriptomes, which changed in two directions/trajectories: one trajectory by the repression of either Pou5f1 or Sox2; the other trajectory by the repression of either Esrrb, Sall4, Nanog, or Tcfap4. The data suggest that the trajectories of gene expression change are already preconfigured by the gene regulatory network and roughly correspond to extraembryonic and embryonic fates of cell differentiation, respectively. These data also indicate the robustness of the pluripotency gene network, as the transient repression of most TFs did not alter the transcriptomes. PMID:23462645

  17. LAND PROPERTY STRUCTURE - A LIMITING FACTOR IN STRENGTHENING THE AGRICULTURAL HOLDINGS

    Directory of Open Access Journals (Sweden)

    Ramona DOBRE

    2013-01-01

    Full Text Available Romania has the largest number of EU holdings. For this purpose, this paper analyses the effect of the excessive agricultural land fragmentation caused by the laws and measures adopted in the previous period. The existence of small holdings is influenced by the land property structures and at the same time, by the training and experience level of holders (heads of holdings. For writing this paper, analyse of statistical data was used in terms of identifying the impact factors which leaded to this holdings situation and, specially, to the fragmentation phenomena, obviously in the agricultural economy. Are highlighted, in order to study the impact, the historical evolution of the Romanian village, the Romanian peasant psychology on property, ownership thirst, desire to have land that would be just his and the need of being the only one who operates it and has benefits of its exploitation. This conception, however, tends to obsession and is generated by a system that has takenthe land from the peasant, leaving him without the essential object of his work. There still exists the fear of no longer having the land, impregnated a lot in their thinking; these resulted in a blockage concerning association, cooperation, lease or any form that could increase the agricultural holdings dimensions. This thinking is manifested in aged population, which is still one of the main problems of the Romanian rural. The effect of these factors, but also of others who will be found in the work act in a negative manner on the formation of a competitive agriculture with an European management orientation. That is why studying them may lead to solutions for the reduction of their influence, the formation of viable social structures and economically valuable.

  18. Geomorphology and accommodation space as limiting factors on tsunami deposition: Chatham Island, southwest Pacific Ocean

    Science.gov (United States)

    Nichol, S. L.; Chagué-Goff, C.; Goff, J. R.; Horrocks, M.; McFadgen, B. G.; Strotz, L. C.

    2010-07-01

    Chatham Island in the southwest Pacific Ocean is exposed on all sides to potential tsunami impact. In historical time, tsunamis are known to have inundated the coast on several occasions, with the largest event in 1868. Coastal dunes along the northeast coast of Chatham Island preserve sedimentary evidence of this and possibly earlier tsunami events, as localised gravel lags. However, these deposits lack a clear stratigraphic context and establishing their age is difficult. This study examines the sediment record in a freshwater wetland at Okawa Point, located directly landward of the dunes where apparent tsunami gravels occur. Sediment descriptions, pollen, foraminifera, chemical data and radiocarbon dates from cores are used to reconstruct the environmental history of the wetland. The record extends from ca. > 43 ka to the present and incorporates glacial, post-glacial and human-influenced phases. Throughout this time the wetland appears to have remained isolated from catastrophic marine inundation. The only evidence for saltwater intrusion is observed in the historic period, via geochemical, grain size and pollen data, which record a marine inundation event that forced the transport of a thin (cm-thick) deposit of dune and beach sand into the seaward edge of the wetland. This is interpreted as the signature of the 1868 tsunami. The lack of more widespread physical evidence for this and other tsunami events in the wetland is attributed to the morphological roughness afforded by coastal dunes and limited accommodation space for Holocene deposits.

  19. Attitude of Healthcare Professionals: A Major Limiting Factor in Organ Donation from Brain-Dead Donors

    Directory of Open Access Journals (Sweden)

    Maciej Kosieradzki

    2014-01-01

    Full Text Available Public attitude toward deceased donor organ recovery in Poland is quite positive, with only 15% opposing to donation of their own organs, yet actual donation rate is only 16/pmp. Moreover, donation rate varies greatly (from 5 to 28 pmp in different regions of the country. To identify the barriers of organ donation, we surveyed 587 physicians involved in brain death diagnosis from regions with low (LDR and high donation rates (HDR. Physicians from LDR were twice more reluctant to start diagnostic procedure when clinical signs of brain death were present (14% versus 5.5% physicians from HDR who would not diagnose death, resp.. Twenty-five percent of LDR physicians (as opposed to 12% of physicians from HDR would either continue with intensive therapy or confirm brain death and limit to the so-called minimal therapy. Only 32% of LDR physicians would proceed with brain death diagnosis regardless of organ donation, compared to 67% in HDR. When donation was not an option, mechanical ventilation would be continued more often in LDR regions (43% versus 26.7%; P<0.01. In conclusion, low donation activity seems to be mostly due to medical staff attitude.

  20. Effects of endurance training only versus same-session combined endurance and strength training on physical performance and serum hormone concentrations in recreational endurance runners.

    Science.gov (United States)

    Schumann, Moritz; Mykkänen, Olli-Pekka; Doma, Kenji; Mazzolari, Raffaele; Nyman, Kai; Häkkinen, Keijo

    2015-01-01

    This study investigated the effects of endurance training only (E, n = 14) and same-session combined training, when strength training is repeatedly preceded by endurance loading (endurance and strength training (E+S), n = 13) on endurance (1000-m running time during incremental field test) and strength performance (1-repetition maximum (1RM) in dynamic leg press), basal serum hormone concentrations, and endurance loading-induced force and hormone responses in recreationally endurance-trained men. E was identical in the 2 groups and consisted of steady-state and interval running, 4-6 times per week for 24 weeks. E+S performed additional mixed-maximal and explosive-strength training (2 times per week) immediately following an incremental running session (35-45 min, 65%-85% maximal heart rate). E and E+S decreased running time at week 12 (-8% ± 5%, p = 0.001 and -7% ± 3%, p Strength performance decreased in E at week 24 (-5% ± 5%, p = 0.014) but was maintained in E+S (between-groups at week 12 and 24, p = 0.014 and 0.011, respectively). Basal serum testosterone and cortisol concentrations remained unaltered in E and E+S but testosterone/sex hormone binding globulin ratio decreased in E+S at week 12 (-19% ± 26%, p = 0.006). At week 0 and 24, endurance loading-induced acute force (-5% to -9%, p = 0.032 to 0.001) and testosterone and cortisol responses (18%-47%, p = 0.013 to p strength training was performed repeatedly after endurance training compared with endurance training only. This was supported by similar acute responses in force and hormonal measures immediately post-endurance loading after the training with sustained 1RM strength in E+S.

  1. Sewage sludge, compost and other representative organic wastes as agricultural soil amendments: Benefits versus limiting factors.

    Science.gov (United States)

    Alvarenga, Paula; Mourinha, Clarisse; Farto, Márcia; Santos, Teresa; Palma, Patrícia; Sengo, Joana; Morais, Marie-Christine; Cunha-Queda, Cristina

    2015-06-01

    Nine different samples of sewage sludges, composts and other representative organic wastes, with potential interest to be used as agricultural soil amendments, were characterized: municipal sewage sludge (SS1 and SS2), agro industrial sludge (AIS), municipal slaughterhouse sludge (MSS), mixed municipal solid waste compost (MMSWC), agricultural wastes compost (AWC), compost produced from agricultural wastes and sewage sludge (AWSSC), pig slurry digestate (PSD) and paper mill wastes (PMW). The characterization was made considering their: (i) physicochemical parameters, (ii) total and bioavailable heavy metals (Cd, Cr, Cu, Ni, Pb, Zn and Hg), (iii) organic contaminants, (iv) pathogenic microorganisms and (v) stability and phytotoxicity indicators. All the sludges, municipal or other, comply with the requirements of the legislation regarding the possibility of their application to agricultural soil (with the exception of SS2, due to its pathogenic microorganisms content), with a content of organic matter and nutrients that make them interesting to be applied to soil. The composts presented, in general, some constraints regarding their application to soil, and their impairment was due to the existence of heavy metal concentrations exceeding the proposed limit of the draft European legislation. As a consequence, with the exception of AWSSC, most compost samples were not able to meet these quality criteria, which are more conservative for compost than for sewage sludge. From the results, the composting of sewage sludge is recommended as a way to turn a less stabilized waste into a material that is no longer classified as a waste and, judging by the results of this work, with lower heavy metal content than the other composted materials, and without sanitation problems. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Human capital and its spatial distribution as limiting factors for the balanced development of Serbia

    Directory of Open Access Journals (Sweden)

    Jokić Vesna

    2015-01-01

    Full Text Available Human capital is one of the key factors of economic and social development. Namely, the growth potential of a territory is largely dependent on human capital that is, on citizen’s creative potential and especially on their education. Society with a better endowment of human capital has a greater development potential. The subject of this paper is Serbia’s human capital seen from the point of view of workforce education structure (20-64 age group. In this paper we present spatial distribution of workforce, i.e. the differences in workforce education levels and polarization of Serbian territory in terms of human capital pool. The result is a typology of municipalities in Serbia based on calculated values of average completed education level - the EMN index. Mapping of the corresponding values was done at the municipality level in order to get a clear distinction and a more accurate picture of spatial disparities in human resources. [Projekat Ministarstva nauke Republike Srbije, br. III47014: The Role and Implementation of the National Spatial Plan and Regional Development Documents in Renewal of Strategic Research, Thinking and Governance in Serbia

  3. Selective breeding for endurance running capacity affects cognitive but not motor learning in rats

    OpenAIRE

    Wikgren, Jan; Mertikas, Georgios; Raussi, Pekka; Tirkkonen, Riina; Äyräväinen, Laura; Pelto-Huikko, Markku; Koch, Lauren G.; Steven L Britton; Kainulainen, Heikki

    2012-01-01

    The ability to utilize oxygen has been shown to affect a wide variety of physiological factors often considered beneficial for survival. As the ability to learn can be seen as one of the core factors of survival in mammals, we studied whether selective breeding for endurance running, an indication of aerobic capacity, also has an effect on learning. Rats selectively bred over 23 generations for their ability to perform forced treadmill running were trained in an appetitively motivated discrim...

  4. Selective breeding for endurance running capacity affects cognitive but not motor learning in rats

    OpenAIRE

    Wikgren, Jan; Mertikas, Georgios; Raussi, Pekka; Tirkkonen, Riina; Äyräväinen, Laura; Pelto-Huikko, Markku; Lauren G. Koch; Britton, Steven L.; Kainulainen, Heikki

    2012-01-01

    The ability to utilize oxygen has been shown to affect a wide variety of physiological factors often considered beneficial for survival. As the ability to learn can be seen as one of the core factors of survival in mammals, we studied whether selective breeding for endurance running, an indication of aerobic capacity, also has an effect on learning. Rats selectively bred over 23 generations for their ability to perform forced treadmill running were trained in an appetitively motivated discrim...

  5. [Food addiction: Definition, measurement and limits of the concept, associated factors, therapeutic and clinical implications].

    Science.gov (United States)

    Cathelain, Sarah; Brunault, Paul; Ballon, Nicolas; Réveillère, Christian; Courtois, Robert

    2016-12-01

    Addictions, which are characterized by the inability to control a behavior despite existence of physical or psychological consequences, have biological, psychological and social determinants. Although the possibility of developing an addiction to some psychoactive substances (e.g. alcohol, tobacco, cannabis) and to gambling (i.e., gambling disorder) is now well demonstrated, the possibility to develop a non-drug addiction (i.e., behavioral addiction) to certain behaviors which provide pleasure (e.g. eating, having sex, buying things) is still in debate. The concept of food addiction, which refers to people who exhibit substance dependence criteria in relation to some high-fat and high-sugar foods, was recently proposed by applying substance dependence DSM criteria to eating behavior. To assess food addiction, the Yale Food Addiction Scale is now the only self-administered questionnaire (diagnosis and estimate of the number of symptoms of food addiction). Prevalence for food addiction is higher in overweight and obese patients, and in patients with certain psychopathological characteristics (i.e., depression, Attention Deficit Hyperactivity Disorder, high impulsivity), in patients who are single and in patients with neurobiological alterations in the reward system. However, it is still unclear whether food addiction is necessary associated with subsequent increase in body weight and/or obesity. An increasing number of studies demonstrated that drug addiction and food addiction shares some similar clinical, neurobiological and psychopathological and sociocultural risk factors. To test the pertinence to include food addiction as an addiction, it would be interesting to conduct future studies in patients who may experience harms related to their food addiction, including not only patients with obesity, but also patients with metabolic syndrome, type 2 diabetes, hypertension, dyslipidemia, atherosclerosis, stroke, or coronary heart disease. Food addiction is a clinical

  6. Strength training prior to endurance exercise: impact on the neuromuscular system, endurance performance and cardiorespiratory responses.

    Science.gov (United States)

    Conceição, Matheus; Cadore, Eduardo Lusa; González-Izal, Miriam; Izquierdo, Mikel; Liedtke, Giane Veiga; Wilhelm, Eurico Nestor; Pinto, Ronei Silveira; Goltz, Fernanda Reistenbach; Schneider, Cláudia Dornelles; Ferrari, Rodrigo; Bottaro, Martim; Kruel, Luiz Fernando Martins

    2014-12-09

    This study aimed to investigate the acute effects of two strength-training protocols on the neuromuscular and cardiorespiratory responses during endurance exercise. Thirteen young males (23.2 ± 1.6 years old) participated in this study. The hypertrophic strength-training protocol was composed of 6 sets of 8 squats at 75% of maximal dynamic strength. The plyometric strength-training protocol was composed of 6 sets of 8 jumps performed with the body weight as the workload. Endurance exercise was performed on a cycle ergometer at a power corresponding to the second ventilatory threshold until exhaustion. Before and after each protocol, a maximal voluntary contraction was performed, and the rate of force development and electromyographic parameters were assessed. After the hypertrophic strength-training and plyometric strength-training protocol, significant decreases were observed in the maximal voluntary contraction and rate of force development, whereas no changes were observed in the electromyographic parameters. Oxygen uptake and a heart rate during endurance exercise were not significantly different among the protocols. However, the time-to-exhaustion was significantly higher during endurance exercise alone than when performed after hypertrophic strength-training or plyometric strength-training (p strength-training, with no oxygen uptake or heart rate changes during the exercise.

  7. Reliability of ultrasound thickness measurement of the abdominal muscles during clinical isometric endurance tests.

    Science.gov (United States)

    ShahAli, Shabnam; Arab, Amir Massoud; Talebian, Saeed; Ebrahimi, Esmaeil; Bahmani, Andia; Karimi, Noureddin; Nabavi, Hoda

    2015-07-01

    The study was designed to evaluate the intra-examiner reliability of ultrasound (US) thickness measurement of abdominal muscles activity when supine lying and during two isometric endurance tests in subjects with and without Low back pain (LBP). A total of 19 women (9 with LBP, 10 without LBP) participated in the study. Within-day reliability of the US thickness measurements at supine lying and the two isometric endurance tests were assessed in all subjects. The intra-class correlation coefficient (ICC) was used to assess the relative reliability of thickness measurement. The standard error of measurement (SEM), minimal detectable change (MDC) and the coefficient of variation (CV) were used to evaluate the absolute reliability. Results indicated high ICC scores (0.73-0.99) and also small SEM and MDC scores for within-day reliability assessment. The Bland-Altman plots of agreement in US measurement of the abdominal muscles during the two isometric endurance tests demonstrated that 95% of the observations fall between the limits of agreement for test and retest measurements. Together the results indicate high intra-tester reliability for the US measurement of the thickness of abdominal muscles in all the positions tested. According to the study's findings, US imaging can be used as a reliable method for assessment of abdominal muscles activity in supine lying and the two isometric endurance tests employed, in participants with and without LBP.

  8. Test-retest reliability of lower limb isokinetic endurance in COPD: a comparison of angular velocities

    Directory of Open Access Journals (Sweden)

    Ribeiro F

    2015-06-01

    Full Text Available Fernanda Ribeiro,* Pierre-Alexis Lépine,* Corine Garceau-Bolduc, Valérie Coats, Étienne Allard, François Maltais, Didier Saey Centre de recherche de l’Institut Universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, Canada *These authors contributed equally to this workBackground: The purpose of this study was to determine and compare the test-retest reliability of quadriceps isokinetic endurance testing at two knee angular velocities in patients with chronic obstructive pulmonary disease (COPD. Methods: After one familiarization session, 14 patients with moderate to severe COPD (mean age 65±4 years; forced expiratory volume in 1 second (FEV1 55%±18% predicted performed two quadriceps isokinetic endurance tests on two separate occasions within a 5–7-day interval. Quadriceps isokinetic endurance tests consisted of 30 maximal knee extensions at angular velocities of 90° and 180° per second, performed in random order. Test-retest reliability was assessed for peak torque, muscle endurance, work slope, work fatigue index, and changes in FEV1 for dyspnea and leg fatigue from rest to the end of the test. The intraclass correlation coefficient, minimal detectable change, and limits of agreement were calculated. Results: High test-retest reliability was identified for peak torque and muscle total work at both velocities. Work fatigue index was considered reliable at 90° per second but not at 180° per second. A lower reliability was identified for dyspnea and leg fatigue scores at both angular velocities. Conclusion: Despite a limited sample size, our findings su pport the use of a 30-maximal repetition isokinetic muscle testing procedure at angular velocities of 90° and 180° per second in patients with moderate to severe COPD. Endurance measurement (total isokinetic work at 90° per second was highly reliable, with a minimal detectable change at the 95% confidence level of 10%. Peak torque and fatigue index

  9. On the discharge capability and its limiting factors of commercial 18650 Li-ion cell at low temperatures

    Science.gov (United States)

    Fan, Jiang

    We here study the discharge capability of commercial 18650 cylindrical lithium-ion cells at low temperatures. The discharge capacity at -20 °C ranges from 67 to 88% of the rated capacity at 0.2 C rate, which is good. However, the cell discharge capacity varies substantially at -30 and -40 °C among the studied cells. It ranges from 2 to 70% of the rated capacity at -30 °C, and 0 to 30% at -40 °C at 0.2 C rate. The cell impedance at 1 kHz increases very little from room temperature down to -20 or -30 °C in general, which does not correlate with the cell discharge capability. However, the dc impedance is increased by a factor of about ten at -30 °C and about twenty at -40 °C from room temperature. The discharge capability at low temperature correlates well with the dc resistance at both room and low temperatures. The limiting factors in the discharge capability at low temperatures and the direction for the future improvement are discussed according to the cell discharge capability, the electrode geometric area, the cell impedance at 1 kHz, and the dc impedance at various temperatures. It appears that the ionic conductivity of the electrolyte and lithium solid diffusion in the electrode do not limit the cell discharge capability, while the lithium diffusion in the SEI layer on the positive surface may be the limiting factor. Cell discharge capability at low temperature does not correlate with cycle life at room temperature.

  10. Maternal health interventions in resource limited countries: a systematic review of packages, impacts and factors for change

    Science.gov (United States)

    2011-01-01

    Background The burden of maternal mortality in resource limited countries is still huge despite being at the top of the global public health agenda for over the last 20 years. We systematically reviewed the impacts of interventions on maternal health and factors for change in these countries. Methods A systematic review was carried out using the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Articles published in the English language reporting on implementation of interventions, their impacts and underlying factors for maternal health in resource limited countries in the past 23 years were searched from PubMed, Popline, African Index Medicus, internet sources including reproductive health gateway and Google, hand-searching, reference lists and grey literature. Results Out of a total of 5084 articles resulting from the search only 58 qualified for systematic review. Programs integrating multiple interventions were more likely to have significant positive impacts on maternal outcomes. Training in emergency obstetric care (EmOC), placement of care providers, refurbishment of existing health facility infrastructure and improved supply of drugs, consumables and equipment for obstetric care were the most frequent interventions integrated in 52% - 65% of all 54 reviewed programs. Statistically significant reduction of maternal mortality ratio and case fatality rate were reported in 55% and 40% of the programs respectively. Births in EmOC facilities and caesarean section rates increased significantly in 71% - 75% of programs using these indicators. Insufficient implementation of evidence-based interventions in resources limited countries was closely linked to a lack of national resources, leadership skills and end-users factors. Conclusions This article presents a list of evidenced-based packages of interventions for maternal health, their impacts and factors for change in resource limited countries. It indicates that no single

  11. Maternal health interventions in resource limited countries: a systematic review of packages, impacts and factors for change.

    Science.gov (United States)

    Nyamtema, Angelo S; Urassa, David P; van Roosmalen, Jos

    2011-04-17

    The burden of maternal mortality in resource limited countries is still huge despite being at the top of the global public health agenda for over the last 20 years. We systematically reviewed the impacts of interventions on maternal health and factors for change in these countries. A systematic review was carried out using the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Articles published in the English language reporting on implementation of interventions, their impacts and underlying factors for maternal health in resource limited countries in the past 23 years were searched from PubMed, Popline, African Index Medicus, internet sources including reproductive health gateway and Google, hand-searching, reference lists and grey literature. Out of a total of 5084 articles resulting from the search only 58 qualified for systematic review. Programs integrating multiple interventions were more likely to have significant positive impacts on maternal outcomes. Training in emergency obstetric care (EmOC), placement of care providers, refurbishment of existing health facility infrastructure and improved supply of drugs, consumables and equipment for obstetric care were the most frequent interventions integrated in 52%-65% of all 54 reviewed programs. Statistically significant reduction of maternal mortality ratio and case fatality rate were reported in 55% and 40% of the programs respectively. Births in EmOC facilities and caesarean section rates increased significantly in 71%-75% of programs using these indicators. Insufficient implementation of evidence-based interventions in resources limited countries was closely linked to a lack of national resources, leadership skills and end-users factors. This article presents a list of evidenced-based packages of interventions for maternal health, their impacts and factors for change in resource limited countries. It indicates that no single magic bullet intervention exists for

  12. Maternal health interventions in resource limited countries: a systematic review of packages, impacts and factors for change

    Directory of Open Access Journals (Sweden)

    Urassa David P

    2011-04-01

    Full Text Available Abstract Background The burden of maternal mortality in resource limited countries is still huge despite being at the top of the global public health agenda for over the last 20 years. We systematically reviewed the impacts of interventions on maternal health and factors for change in these countries. Methods A systematic review was carried out using the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA. Articles published in the English language reporting on implementation of interventions, their impacts and underlying factors for maternal health in resource limited countries in the past 23 years were searched from PubMed, Popline, African Index Medicus, internet sources including reproductive health gateway and Google, hand-searching, reference lists and grey literature. Results Out of a total of 5084 articles resulting from the search only 58 qualified for systematic review. Programs integrating multiple interventions were more likely to have significant positive impacts on maternal outcomes. Training in emergency obstetric care (EmOC, placement of care providers, refurbishment of existing health facility infrastructure and improved supply of drugs, consumables and equipment for obstetric care were the most frequent interventions integrated in 52% - 65% of all 54 reviewed programs. Statistically significant reduction of maternal mortality ratio and case fatality rate were reported in 55% and 40% of the programs respectively. Births in EmOC facilities and caesarean section rates increased significantly in 71% - 75% of programs using these indicators. Insufficient implementation of evidence-based interventions in resources limited countries was closely linked to a lack of national resources, leadership skills and end-users factors. Conclusions This article presents a list of evidenced-based packages of interventions for maternal health, their impacts and factors for change in resource limited countries

  13. Whole blood selenium concentrations in endurance horses.

    Science.gov (United States)

    Haggett, Emily; Magdesian, K Gary; Maas, John; Puschner, Birgit; Higgins, Jamie; Fiack, Ciara

    2010-11-01

    Exercise causes an increase in the production of reactive oxygen species, which can result in oxidant/antioxidant disequilibrium. Deficiency of antioxidants can further alter this balance in favor of pro-oxidation. Selenium (Se) is one of many antioxidant catalysts, as a component of the glutathione peroxidase enzymes. Soils and forages vary widely in Se concentration and a deficient diet can lead to sub-clinical or clinical deficiency in horses. Endurance horses are prone to oxidative stress during long periods of aerobic exercise and their performance could be affected by Se status. This study investigated the blood Se concentration in a group of endurance horses (n=56) residing and competing in California, a state containing several regions that tend to produce Se-deficient forages. The rate of Se deficiency in this group of horses was low, with only one horse being slightly below the reference range. Higher blood Se concentrations were not associated with improved performance in terms of ride time. There was no significant difference in Se concentration between horses that completed the ride and those that were disqualified, although blood Se concentrations were significantly higher in horses that received oral Se supplementation. An increase in blood Se concentration was observed following exercise and this warrants further study.

  14. Major adverse cardiac events during endurance sports.

    Science.gov (United States)

    Belonje, Anne; Nangrahary, Mary; de Swart, Hans; Umans, Victor

    2007-03-15

    Major adverse cardiac events in endurance exercise are usually due to underlying and unsuspected heart disease. The investigators present an analysis of major adverse cardiac events that occurred during 2 consecutive annual long distance races (a 36-km beach cycling race and a 21-km half marathon) over the past 5 years. All patients with events were transported to the hospital. Most of the 62,862 participants were men (77%; mean age 40 years). Of these, 4 men (3 runners, 1 cyclist; mean age 48 years) collapsed during (n = 2) or shortly after the races, rendering a prevalence of 0.006%. Two patients collapsed after developing chest pain, 1 of whom needed resuscitation at the event site, which was successful. These patients had acute myocardial infarctions and underwent primary angioplasty. The third patient was resuscitated at the site but did not have coronary disease or inducible ventricular tachycardia or ventricular fibrillation and collapsed presumably because of catecholamine-induced ventricular fibrillation. The fourth patient experienced heat stroke and had elevated creatine kinase-MB and troponins in the absence of electrocardiographic changes. In conclusion, the risk for major adverse cardiac events during endurance sports in well-trained athletes is very low.

  15. The energetics of ultra-endurance running.

    Science.gov (United States)

    Lazzer, Stefano; Salvadego, Desy; Rejc, Enrico; Buglione, Antonio; Antonutto, Guglielmo; di Prampero, Pietro Enrico

    2012-05-01

    Our objective was to determine the effects of long-lasting endurance events on the energy cost of running (C(r)), and the role of maximal oxygen uptake (VO(2max)), its fractional utilisation (F) and C(r) in determining the performance. Ten healthy runners (age range 26-59 years) participated in an ultra-endurance competition consisting of three running laps of 22, 48 and 20 km on three consecutive days in the North-East of Italy. Anthropometric characteristics and VO(2max) by a graded exercise test on a treadmill were determined 5 days before and 5 days after the competition. In addition, C(r) was determined on a treadmill before and after each running lap. Heart rate (HR) was recorded throughout the three laps. Results revealed that mean C(r) of the individual laps did not increase significantly with lap number (P = 0.200), thus ruling out any chronic lap effect. Even so, however, at the end of lap 3, C(r) was 18.0% (P increase of C(r-mean) during the competition yields to marked worsening of the performance, and (2) the three variables F, VO(2max) and C(r-mean) combined as described above explaining 87% of the total competition time variance.

  16. Endurance testing with Li/Na electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Ong, E.T.; Remick, R.J.; Sishtla, C.I. [Institute of Gas Technology, Des Plaines, IL (United States)

    1996-12-31

    The Institute of Gas Technology (IGT), under subcontract to M-C Power Corporation under DOE funding, has been operating bench-scale fuel cells to investigate the performance and endurance issues of the Li/Na electrolyte because it offers higher ionic conductivity, higher exchange current densities, lower vapor pressures, and lower cathode dissolution rates than the Li/K electrolyte. These cells have continued to show higher performance and lower decay rates than the Li/K cells since the publication of our two previous papers in 1994. In this paper, test results of two long-term 100-cm{sup 2} bench scale cells are discussed. One cell operated continuously at 160 mA/cm{sup 2} for 17,000 hours with reference gases (60H{sub 2}/20CO{sub 2}/20H{sub 2}O fuel at 75% utilization and 30CO{sub 2}/70 air oxidant humidified at room temperature at 50% utilization). The other cell operated at 160 mA/cm{sup 2} for 6900 hours at 3 atm with system gases (64H{sub 2}/16CO{sub 2}/20H{sub 2}O at 75% utilization and an M-C Power system-defined oxidant at 40% utilization). Both cells have shown the highest performance and longest endurance among IGT cells operated to date.

  17. Endurance training facilitates myoglobin desaturation during muscle contraction in rat skeletal muscle.

    Science.gov (United States)

    Takakura, Hisashi; Furuichi, Yasuro; Yamada, Tatsuya; Jue, Thomas; Ojino, Minoru; Hashimoto, Takeshi; Iwase, Satoshi; Hojo, Tatsuya; Izawa, Tetsuya; Masuda, Kazumi

    2015-03-24

    At onset of muscle contraction, myoglobin (Mb) immediately releases its bound O2 to the mitochondria. Accordingly, intracellular O2 tension (PmbO2) markedly declines in order to increase muscle O2 uptake (mVO2). However, whether the change in PmbO2 during muscle contraction modulates mVO2 and whether the O2 release rate from Mb increases in endurance-trained muscles remain unclear. The purpose of this study was, therefore, to determine the effect of endurance training on O2 saturation of Mb (SmbO2) and PmbO2 kinetics during muscle contraction. Male Wistar rats were subjected to a 4-week swimming training (Tr group; 6 days per week, 30 min × 4 sets per day) with a weight load of 2% body mass. After the training period, deoxygenated Mb kinetics during muscle contraction were measured using near-infrared spectroscopy under hemoglobin-free medium perfusion. In the Tr group, the VmO2peak significantly increased by 32%. Although the PmbO2 during muscle contraction did not affect the increased mVO2 in endurance-trained muscle, the O2 release rate from Mb increased because of the increased Mb concentration and faster decremental rate in SmbO2 at the maximal twitch tension. These results suggest that the Mb dynamics during muscle contraction are contributing factors to faster VO2 kinetics in endurance-trained muscle.

  18. Increased fatigue resistance of respiratory muscles during exercise after respiratory muscle endurance training

    OpenAIRE

    Verges, S; Lenherr, O; Haner, A C; Schulz, C.; Spengler, C M

    2007-01-01

    Respiratory muscle fatigue develops during exhaustive exercise and can limit exercise performance. Respiratory muscle training, in turn, can increase exercise performance. We investigated whether respiratory muscle endurance training (RMT) reduces exercise-induced inspiratory and expiratory muscle fatigue. Twenty-one healthy, male volunteers performed twenty 30-min sessions of either normocapnic hyperpnoea (n = 13) or sham training (CON, n = 8) over 4-5 wk. Before and after training, subjects...

  19. Beneficial metabolic adaptations due to endurance exercise training in the fasted state

    OpenAIRE

    Van Proeyen, Karen; Szlufcik, Karolina; Nielens, Henri; Ramaekers, Monique; Hespel, Peter

    2010-01-01

    Training with limited carbohydrate availability can stimulate adaptations in muscle cells to facilitate energy production via fat oxidation. Here we investigated the effect of consistent training in the fasted state, vs. training in the fed state, on muscle metabolism and substrate selection during fasted exercise. Twenty young male volunteers participated in a 6-wk endurance training program (1-1.5 h cycling at ∼70% Vo(₂max), 4 days/wk) while receiving isocaloric carbohydrate-rich diets. Hal...

  20. Distribution pattern and limiting factors of vegetation in coal waste pile of Xinzhuangzi coal mine in Huainan

    Institute of Scientific and Technical Information of China (English)

    CHU Zhao-xia; WANG Shun-chang; WANG Xing-ming

    2012-01-01

    In China,coal mine spoils have traditionally been dumped in cone-shaped heaps that have the potential to pollute air,soil and water environments.The coal waste pile occupies lots of arable land and endangers the ecological system in the coal mine district.Vegetation restoration is an efficient approach for controlling the environment pollution of coal waste pile,and is also a topic of current interest in restoration ecology and degradation system ecology.This study focused on the distribution pattern and limiting factors of vegetation in coal waste pile of Xinzhuangzi Coal Mine in Huainan.The results show that two stable plant communities (Synodon dactylon+Erigeron bonariensis.L+Setaria viridis community and Humulus scanden+Erigeron bonariensis.L community) exist at the bottom of the pile.Synodon dactylon and Erigeron bonariensis.L have much higher values of summed dominance ratio,which denote that these two species can be used for restoration of coal waste piles.The high levels of pH (8.77) and salinity,low levels of total P and total K in coal mine spoil can be the limiting factors for the residence and growth of vegetation.

  1. Acetabular stress fractures in military endurance athletes and recruits: incidence and MRI and scintigraphic findings

    Energy Technology Data Exchange (ETDEWEB)

    Williams, T.R. [Portsmouth Naval Medical Center, Radiology Department, Charette Health Care Center, Portsmouth, VA (United States); Puckett, M.L.; Shin, A.Y.; Gorman, J.D. [Naval Medical Center San Diego, Radiology Department, San Diego, CA (United States); Denison, G. [US Naval Hospital Guam (United States)

    2002-05-01

    Objective: To evaluate the incidence and the MRI and scintigraphic appearance of acetabular stress (fatigue) fractures in military endurance athletes and recruits. Design and patients: One hundred and seventy-eight active duty military endurance trainees with a history of activity-related hip pain were evaluated by both MRI and bone scan over a 2-year period. Patients in the study ranged in age from 17 to 45 years. They had hip pain related to activity and had plain radiographs of the hip and pelvis that were interpreted as normal or equivocal. The study was originally designed to evaluate the MRI and scintigraphic appearance of femoral neck stress fractures. Patients had scintigraphy and a limited MRI examination (coronal imaging only) within 48 h of the bone scan. Twelve patients demonstrated imaging findings compatible with acetabular stress fractures. Results: Stress fractures are common in endurance athletes and in military populations; however, stress fracture of the acetabulum is uncommon. Twelve of 178 patients (6.7%) in our study had imaging findings consistent with acetabular stress fractures. Two patterns were identified. Seven of the 12 (58%) patients had acetabular roof stress fractures. In this group, two cases of bilateral acetabular roof stress fractures were identified, one with a synchronous tensile sided femoral neck stress fracture. The remaining five of 12 (42%) patients had anterior column stress fractures, rarely occurring in isolation, and almost always occurring with inferior pubic ramus stress fracture (4 of 5, or 80%). One case of bilateral anterior column stress fractures was identified without additional sites of injury. Conclusions: Stress fractures are commonplace in military populations, especially endurance trainees. Acetabular stress fractures are rare and therefore unrecognized, but do occur and may be a cause for activity-related hip pain in a small percentage of military endurance athletes and recruits. (orig.)

  2. Factors affecting the sensitivity and detection limits of MRI, CT, and SPECT for multimodal diagnostic and therapeutic agents.

    Science.gov (United States)

    Seevinck, Peter R; Seppenwoolde, Jan-Henry; de Wit, Tim C; Nijsen, Johannes F W; Beekman, Freek J; van Het Schip, Alfred D; Bakker, Chris J G

    2007-05-01

    Noninvasive imaging techniques like magnetic resonance imaging (MRI), computed tomography (CT) and single photon emission computed tomography (SPECT) play an increasingly important role in the diagnostic workup and treatment of cancerous disease. In this context, a distinct trend can be observed towards the development of contrast agents and radiopharmaceuticals that open up perspectives on a multimodality imaging approach, involving all three aforementioned techniques. To promote insight into the potentialities of such an approach, we prepared an overview of the strengths and limitations of the various imaging techniques, in particular with regard to their capability to quantify the spatial distribution of a multimodal diagnostic agent. To accomplish this task, we used a two-step approach. In the first step, we examined the situation for a particular therapeutic anti-cancer agent with multimodal imaging opportunities, viz. holmium-loaded microspheres (HoMS). Physical phantom experiments were performed to enable a comparative evaluation of the three modalities assuming the use of standard equipment, standard clinical scan protocols, and signal-known-exactly conditions. These phantom data were then analyzed so as to obtain first order estimates of the sensitivity and detection limits of MRI, CT and SPECT for HoMS. In the second step, the results for HoMS were taken as a starting point for a discussion of the factors affecting the sensitivity and detection limits of MRI, CT and SPECT for multimodal agents in general. In this, emphasis was put on the factors that must be taken into account when extrapolating the findings for HoMS to other diagnostic tasks, other contrast agents, other experimental conditions, and other scan protocols.

  3. Nutritional habits among high-performance endurance athletes

    Directory of Open Access Journals (Sweden)

    Marius Baranauskas

    2015-01-01

    Conclusions: The diet of highly trained endurance athletes does not fully meet their requirements and in this situation cannot ensure maximum adaptation to very intense and/or long-duration physical loads. The diet of highly trained endurance athletes must be optimized, adjusted and individualized. Particular attention should be focused on female athletes.

  4. Comparative analysis of endurance of not hearing and hearing students

    Directory of Open Access Journals (Sweden)

    Iwańska Dagmara

    2013-11-01

    Full Text Available Study aim: Sport participation is important for deaf children, as participants experience physical, psychological and social benefits [23]. This study is a summary of four year’s researches on the endurance level of deaf and well hearing girls and boys. The aim of this study was to compare endurance of not hearing and hearing students.

  5. Lower Muscle Endurance in Patients with Alcoholic Liver Disease

    Science.gov (United States)

    Andersen, Henning; Aagaard, Niels K.; Jakobsen, Johannes; Dorup, Inge; Vilstrup, Hendrik

    2012-01-01

    Patients with alcoholic liver disease often complain of restricted physical capacity, which could be due to decreased muscle endurance. The aim of this study was to assess the muscular endurance in patients with alcoholic liver disease. In a cross sectional study, 24 patients with alcoholic liver disease and 22 controls were evaluated using…

  6. Lower Muscle Endurance in Patients with Alcoholic Liver Disease

    Science.gov (United States)

    Andersen, Henning; Aagaard, Niels K.; Jakobsen, Johannes; Dorup, Inge; Vilstrup, Hendrik

    2012-01-01

    Patients with alcoholic liver disease often complain of restricted physical capacity, which could be due to decreased muscle endurance. The aim of this study was to assess the muscular endurance in patients with alcoholic liver disease. In a cross sectional study, 24 patients with alcoholic liver disease and 22 controls were evaluated using…

  7. 76 FR 72243 - Proposed Information Collection (Operation Enduring Freedom/Operation Iraqi Freedom Veterans...

    Science.gov (United States)

    2011-11-22

    ... facilities for returning Operation Enduring Freedom/ Operation Iraqi Freedom veterans and their families... AFFAIRS Proposed Information Collection (Operation Enduring Freedom/ Operation Iraqi Freedom Veterans.... Title: Operation Enduring Freedom/Operation Iraqi Freedom Veterans Health Needs Assessment, VA Form 10...

  8. Diffusion limitations and metabolic factors associated with inhibition and recovery of photosynthesis following cold stress in Elymus nutans Griseb.

    Science.gov (United States)

    Fu, Juanjuan; Gates, Roger N; Xu, Yuefei; Hu, Tianming

    2016-10-01

    attributed to reduced diffusion limitations and rapid recuperation of metabolic factors.

  9. Older Asian Americans and Pacific Islanders with Activities of Daily Living (ADL Limitations: Immigration and Other Factors Associated with Institutionalization

    Directory of Open Access Journals (Sweden)

    Esme Fuller-Thomson

    2012-09-01

    Full Text Available This study determined the national prevalence and profile of Asian Americans with Activities of Daily Living (ADL limitations and identified factors associated with institutionalization. Data were obtained from 2006 American Community Survey, which replaced the long-form of the US Census. The data are nationally representative of both institutionalized and community-dwelling older adults. Respondents were Vietnamese (n = 203, Korean (n = 131, Japanese (n = 193, Filipino (n = 309, Asian Indian (n = 169, Chinese (n = 404, Hawaiian/Pacific Islander (n = 54, and non-Hispanic whites (n = 55,040 aged 55 and over who all had ADL limitations. The prevalence of institutionalized among those with ADL limitations varies substantially from 4.7% of Asian Indians to 18.8% of Korean Americans with ADL limitations. Every AAPI group had a lower prevalence of institutionalization than disabled Non-Hispanic whites older adults (23.8% (p < 0.001. After adjustment for socio-demographic characteristics, Asian Indians, Vietnamese, Japanese, Filipino, and Chinese had significantly lower odds of institutionalization than non-Hispanic whites (OR = 0.29, 0.31, 0.58, 0.51, 0.70, respectively. When the sample was restricted to AAPIs, the odds of institutionalization were higher among those who were older, unmarried, cognitively impaired and those who spoke English at home. This variation suggests that aggregating data across the AAPI groups obscures meaningful differences among these subpopulations and substantial inter-group differences may have important implications in the long-term care setting.

  10. Evaluation of a 7-Gene Genetic Profile for Athletic Endurance Phenotype in Ironman Championship Triathletes.

    Directory of Open Access Journals (Sweden)

    Rebecca Grealy

    Full Text Available Polygenic profiling has been proposed for elite endurance performance, using an additive model determining the proportion of optimal alleles in endurance athletes. To investigate this model's utility for elite triathletes, we genotyped seven polymorphisms previously associated with an endurance polygenic profile (ACE Ins/Del, ACTN3 Arg577Ter, AMPD1 Gln12Ter, CKMM 1170bp/985+185bp, HFE His63Asp, GDF8 Lys153Arg and PPARGC1A Gly482Ser in a cohort of 196 elite athletes who participated in the 2008 Kona Ironman championship triathlon. Mean performance time (PT was not significantly different in individual marker analysis. Age, sex, and continent of origin had a significant influence on PT and were adjusted for. Only the AMPD1 endurance-optimal Gln allele was found to be significantly associated with an improvement in PT (model p = 5.79 x 10-17, AMPD1 genotype p = 0.01. Individual genotypes were combined into a total genotype score (TGS; TGS distribution ranged from 28.6 to 92.9, concordant with prior studies in endurance athletes (mean±SD: 60.75±12.95. TGS distribution was shifted toward higher TGS in the top 10% of athletes, though the mean TGS was not significantly different (p = 0.164 and not significantly associated with PT even when adjusted for age, sex, and origin. Receiver operating characteristic curve analysis determined that TGS alone could not significantly predict athlete finishing time with discriminating sensitivity and specificity for three outcomes (less than median PT, less than mean PT, or in the top 10%, though models with the age, sex, continent of origin, and either TGS or AMPD1 genotype could. These results suggest three things: that more sophisticated genetic models may be necessary to accurately predict athlete finishing time in endurance events; that non-genetic factors such as training are hugely influential and should be included in genetic analyses to prevent confounding; and that large collaborations may be necessary

  11. Endurance exercise after orange ingestion anaphylaxis

    Directory of Open Access Journals (Sweden)

    Manu Gupta

    2016-01-01

    Full Text Available Endurance exercise after orange ingestion cause anaphylaxis which is food-dependent exercise-induced anaphylaxis (FDEIA which is a form of exercise-induced anaphylaxis. In this article, an individual develops symptoms such as flushing, itching, urticaria, angioedema, and wheezing after eating a food allergen and proceeds to exercise. Neither the food alone nor exercise alone is sufficient to induce a reaction. This case report describes a 36-year-old asthmatic male athlete who experienced nausea, vomiting, flushing, urticaria, and facial swelling while exercising in a gymnasium after eating oranges. Neither oranges alone nor exercise alone induced the reaction. Total avoidance of suspected food allergens would be ideal. Persons with FDEIA should keep at hand an emergency kit with antihistamines, injectable rapid action corticoids, and adrenaline.

  12. The enduring scientific contributions of Sigmund Freud.

    Science.gov (United States)

    Gedo, John E

    2002-01-01

    Through the development of a novel observational method, Sigmund Freud made possible the collection of reliable data about man's inner life. The scientific hypotheses he formulated about these formed the initial version of psychoanalysis. Many of these first thoughts have had to be revised in the light of subsequent scientific findings about the operations of the central nervous system, but even these refuted propositions often had much heuristic value. Despite the passage of a whole century, many Freudian hypotheses have retained their scientific standing. Most important among these was Freud's realization that human thought is usually unconscious. His understanding of the role of the automatic repetition of basic patterns of behavior, of the fateful consequences of early childhood emotional vicissitudes in structuring enduring mental dispositions, and of the distinction between two distinct modes of thinking are the most significant among his many contributions.

  13. Effect of acute endurance and resistance exercise on endocrine hormones directly related to lipolysis and skeletal muscle protein synthesis in adult individuals with obesity.

    Science.gov (United States)

    Hansen, Dominique; Meeusen, Romain; Mullens, Annelies; Dendale, Paul

    2012-05-01

    In subjects with obesity, the implementation of long-term exercise intervention increases lean tissue mass and lowers adipose tissue mass. However, data indicate a blunted lipolytic response, and/or skeletal muscle protein synthesis, when subjects with obesity are exposed to acute endurance or resistance exercise, respectively. Therefore, subjects with obesity seem to display a suboptimal physiological response to acute exercise stimuli. It might be hypothesized that hormonal disturbances contribute, at least in part, to these abnormal physiological reactions in the obese. This review discusses the impact of acute endurance and resistance exercise on endocrine hormones directly related to lipolysis and/or skeletal muscle protein synthesis (insulin, [nor]epinephrine, cortisol, growth hormone, testosterone, triiodothyronine, atrial natriuretic peptide, insulin-like growth factor-1), as well as the impact of long-term endurance and resistance exercise intervention on these hormonal responses to acute endurance and resistance exercise. In the obese, some endocrinological disturbances during acute endurance and resistance exercise have been identified: a blunted blood growth hormone, atrial natriuretic peptide and epinephrine release, and greater cortisol and insulin release. These hormonal disturbances might contribute to a suppressed lipolytic response, and/or suppressed skeletal muscle protein synthesis, as a result of acute endurance or resistance exercise, respectively. In subjects with obesity, the impact of acute endurance and resistance exercise on other endocrine hormones (norepinephrine, testosterone, triiodothyronine, insulin-like growth factor-1) remains elusive. Furthermore, whether long-term endurance and resistance exercise intervention might reverse these hormonal disturbances during acute endurance and resistance exercise in these individuals remains unknown.

  14. Relationship between Core Stability Muscle Endurance and Static and Dynamic Balance in Basketball Players

    OpenAIRE

    farzaneh saki; masumeh Baghban

    2016-01-01

    Objective: Balancing is the most basic function of the neuromuscular system in performing all simple and complex activities that contribute to health-related physical fitness. Core stability may be a contributing factor to static and dynamic balance. The aim of this study was to investigate the relationship between core stability muscle endurance and static and dynamic balance in basketball players. Methods: 100 basketball players (50 female and 50 male players) were selected randomly bas...

  15. Brain-derived neurotrophic factor (BDNF) serum basal levels is not affected by power training in mobility-limited older adults - A randomized controlled trial

    DEFF Research Database (Denmark)

    Hvid, Lars G; Nielsen, Martin KF; Simonsen, Casper

    2017-01-01

    Brain-derived neurotrophic factor (BDNF) is a potential important factor involved in neuroplasticity, and may be a mediator for eliciting adaptations in neuromuscular function and physical function in older individuals following physical training. As power training taxes the neural system to a very...... not appear to be a major mechanistic factor mediating neuroplasticity in mobility-limited older adults....

  16. Small sized slip-ring capsule endurance testing

    Science.gov (United States)

    Mondier, Jean-Bernard

    2005-07-01

    Slip-ring capsules are mechanical units used to carry electrical signals or power currents through a rotating joint. They are used either in solar array drive mechanisms (SADM) or in scientific instruments like radiometers. Analyses of the latest missions show that the slip-rings requirements are more and more demanding. For example, the number of in-orbit mechanical cycles keeps increasing. As a result, a signal slip-ring technology, which had been successfully tested for a given need, now has to improve its performances. It was therefore interesting to try to reach the slip-rings technical limits by testing them beyond the required performance of already known space missions. Slip-rings units are currently used in mechanisms such as SADM for the CNES Proteus and Myriade satellite family. They can be also found in the payload instruments of the Megha-Tropiques satellite project, namely Madras and Scarab. A selected hardware was tested at the mechanism endurance laboratory of the CNES, in Toulouse. The typical in-orbit rotation speed was increased in order to limit the test duration to 2 years. The main interest of this work was to provide a continuous slip-ring performance status and a large set of engineering data. The main test results are presented and discussed. The following lines also report a part of the hardware detailed inspection and the lessons learned.

  17. Observation of the Fundamental Nyquist Noise Limit in an Ultra-High $Q$-Factor Cryogenic Bulk Acoustic Wave Cavity

    CERN Document Server

    Goryachev, Maxim; van Kann, Frank; Galliou, Serge; Tobar, Michael E

    2014-01-01

    Thermal Nyquist noise fluctuations of high-$Q$ Bulk Acoustic Wave (BAW) cavities have been observed at cryogenic temperatures with a DC Superconducting Quantum Interference Device (SQUID) amplifier. High $Q$ modes with bandwidths of few tens of milliHz produce thermal fluctuations with a Signal-To-Noise ratio of up to 23dB. The estimated effective temperature from the Nyquist noise is in good agreement with the physical temperature of the device, confirming the validity of the equivalent circuit model and the non-existence of any excess resonator self-noise. The measurements also confirm that the quality factor remains extremely high ($Q>10^8$ at low order overtones) for very weak (thermal) system motion at low temperatures, when compared to values measured with relatively strong external excitation. This result represents an enabling step towards operating such a high-Q acoustic device at the standard quantum limit.

  18. Modeling of the ComRS signaling pathway reveals the limiting factors controlling competence in Streptococcus thermophilus

    Directory of Open Access Journals (Sweden)

    Laurie eHaustenne

    2015-12-01

    Full Text Available In streptococci, entry in competence is dictated by ComX abundance. In Streptococcus thermophilus, production of ComX is transient and tightly regulated during growth: it is positively regulated by the cell-cell communication system ComRS during the activation phase and negatively regulated during the shut-off phase by unidentified late competence gene(s. Interestingly, most S. thermophilus strains are not or weakly transformable in permissive growth conditions (i.e. chemically defined medium, CDM, suggesting that some players of the ComRS regulatory pathway are limiting. Here, we combined mathematical modeling and experimental approaches to identify the components of the ComRS system which are critical for both dynamics and amplitude of ComX production in S. thermophilus. We built a deterministic, population-scaled model of the time-course regulation of specific ComX production in CDM growth conditions. Strains LMD-9 and LMG18311 were respectively selected as representative of highly and weakly transformable strains. Results from in silico simulations and in vivo luciferase activities show that ComR concentration is the main limiting factor for the level of comX expression and controls the kinetics of spontaneous competence induction in strain LMD-9. In addition, the model predicts that the poor transformability of strain LMG18311 results from a 10-fold lower comR expression level compared to strain LMD-9. In agreement, comR overexpression in both strains was shown to induce higher competence levels with deregulated kinetics patterns during growth. In conclusion, we propose that the level of ComR production is one important factor that could explain competence heterogeneity among S. thermophilus strains.

  19. Modeling of the ComRS Signaling Pathway Reveals the Limiting Factors Controlling Competence in Streptococcus thermophilus

    Science.gov (United States)

    Haustenne, Laurie; Bastin, Georges; Hols, Pascal; Fontaine, Laetitia

    2015-01-01

    In streptococci, entry in competence is dictated by ComX abundance. In Streptococcus thermophilus, production of ComX is transient and tightly regulated during growth: it is positively regulated by the cell-cell communication system ComRS during the activation phase and negatively regulated during the shut-off phase by unidentified late competence gene(s). Interestingly, most S. thermophilus strains are not or weakly transformable in permissive growth conditions (i.e., chemically defined medium, CDM), suggesting that some players of the ComRS regulatory pathway are limiting. Here, we combined mathematical modeling and experimental approaches to identify the components of the ComRS system which are critical for both dynamics and amplitude of ComX production in S. thermophilus. We built a deterministic, population-scaled model of the time-course regulation of specific ComX production in CDM growth conditions. Strains LMD-9 and LMG18311 were respectively selected as representative of highly and weakly transformable strains. Results from in silico simulations and in vivo luciferase activities show that ComR concentration is the main limiting factor for the level of comX expression and controls the kinetics of spontaneous competence induction in strain LMD-9. In addition, the model predicts that the poor transformability of strain LMG18311 results from a 10-fold lower comR expression level compared to strain LMD-9. In agreement, comR overexpression in both strains was shown to induce higher competence levels with deregulated kinetics patterns during growth. In conclusion, we propose that the level of ComR production is one important factor that could explain competence heterogeneity among S. thermophilus strains. PMID:26733960

  20. Expression of factor H binding protein of meningococcus responds to oxygen limitation through a dedicated FNR-regulated promoter.

    Science.gov (United States)

    Oriente, Francesca; Scarlato, Vincenzo; Delany, Isabel

    2010-02-01

    Factor H binding protein (fHBP) is a surface-exposed lipoprotein in Neisseria meningitidis, which is a component of several investigational vaccines against serogroup B meningococcus (MenB) currently in development. fHBP enables the bacterium to evade complement-mediated killing by binding factor H, a key downregulator of the complement alternative pathway, and, in addition, fHBP is important for meningococcal survival in the presence of the antimicrobial peptide LL-37. In this study, we investigate the molecular mechanisms involved in transcription and regulation of the fHBP-encoding gene, fhbp. We show that the fHBP protein is expressed from two independent transcripts: one bicistronic transcript that includes the upstream gene and a second shorter monocistronic transcript from its own dedicated promoter, P(fhbp). Transcription from the promoter P(fhbp) responds to oxygen limitation in an FNR-dependent manner, and, accordingly, the FNR protein binds to a P(fhbp) probe in vitro. Furthermore, expression in meningococci of a constitutively active FNR mutant results in the overexpression of the fHBP protein. Finally, the analysis of fHBP regulation was extended to a panel of strains expressing different fHBP allelic variants at different levels, and we demonstrate that FNR is involved in the regulation of this antigen in all but one of the strains tested. Our data suggest that oxygen limitation may play an important role in inducing the expression of fHBP from a dedicated FNR-regulated promoter. This implies a role for this protein in microenvironments lacking oxygen, for instance in the submucosa or intracellularly, in addition to its demonstrated role in serum resistance in the blood.

  1. Limited polymorphism in Plasmodium falciparum ookinete surface antigen, von Willebrand factor A domain-related protein from clinical isolates

    Directory of Open Access Journals (Sweden)

    Eisen Damon P

    2006-07-01

    Full Text Available Abstract Background As malaria becomes increasingly drug resistant and more costly to treat, there is increasing urgency to develop effective vaccines. In comparison to other stages of the malaria lifecycle, sexual stage antigens are under less immune selection pressure and hence are likely to have limited antigenic diversity. Methods Clinical isolates from a wide range of geographical regions were collected. Direct sequencing of PCR products was then used to determine the extent of polymorphisms for the novel Plasmodium falciparum sexual stage antigen von Willebrand Factor A domain-related Protein (PfWARP. These isolates were also used to confirm the extent of diversity of sexual stage antigen Pfs28. Results PfWARP was shown to have non-synonymous substitutions at 3 positions and Pfs28 was confirmed to have a single non-synonymous substitution as previously described. Conclusion This study demonstrates the limited antigenic diversity of two prospective P. falciparum sexual stage antigens, PfWARP and Pfs28. This provides further encouragement for the proceeding with vaccine trials based on these antigens.

  2. Perceptual and Cognitive Factors Imposing "Speed Limits" on Reading Rate: A Study with the Rapid Serial Visual Presentation.

    Science.gov (United States)

    Primativo, Silvia; Spinelli, Donatella; Zoccolotti, Pierluigi; De Luca, Maria; Martelli, Marialuisa

    2016-01-01

    Adults read at high speed, but estimates of their reading rate vary greatly, i.e., from 100 to 1500 words per minute (wpm). This discrepancy is likely due to different recording methods and to the different perceptual and cognitive processes involved in specific test conditions. The present study investigated the origins of these notable differences in RSVP reading rate (RR). In six experiments we investigated the role of many different perceptual and cognitive variables. The presence of a mask caused a steep decline in reading rate, with an estimated masking cost of about 200 wpm. When the decoding process was isolated, RR approached values of 1200 wpm. When the number of stimuli exceeded the short-term memory span, RR decreased to 800 wpm. The semantic context contributed to reading speed only by a factor of 1.4. Finally, eye movements imposed an upper limit on RR (around 300 wpm). Overall, data indicate a speed limit of 300 wpm, which corresponds to the time needed for eye movement execution, i.e., the most time consuming mechanism. Results reconcile differences in reading rates reported by different laboratories and thus provide suggestions for targeting different components of reading rate.

  3. Interference between concurrent resistance and endurance exercise: molecular bases and the role of individual training variables.

    Science.gov (United States)

    Fyfe, Jackson J; Bishop, David J; Stepto, Nigel K

    2014-06-01

    Concurrent training is defined as simultaneously incorporating both resistance and endurance exercise within a periodized training regime. Despite the potential additive benefits of combining these divergent exercise modes with regards to disease prevention and athletic performance, current evidence suggests that this approach may attenuate gains in muscle mass, strength, and power compared with undertaking resistance training alone. This has been variously described as the interference effect or concurrent training effect. In recent years, understanding of the molecular mechanisms mediating training adaptation in skeletal muscle has emerged and provided potential mechanistic insight into the concurrent training effect. Although it appears that various molecular signaling responses induced in skeletal muscle by endurance exercise can inhibit pathways regulating protein synthesis and stimulate protein breakdown, human studies to date have not observed such molecular 'interference' following acute concurrent exercise that might explain compromised muscle hypertrophy following concurrent training. However, given the multitude of potential concurrent training variables and the limitations of existing evidence, the potential roles of individual training variables in acute and chronic interference are not fully elucidated. The present review explores current evidence for the molecular basis of the specificity of training adaptation and the concurrent interference phenomenon. Additionally, insights provided by molecular and performance-based concurrent training studies regarding the role of individual training variables (i.e., within-session exercise order, between-mode recovery, endurance training volume, intensity, and modality) in the concurrent interference effect are discussed, along with the limitations of our current understanding of this complex paradigm.

  4. DRIVING AND LIMITING FACTORS IN THE FARM MANAGEMENT BY YOUNG FARMERS IN THE CONTEXT OF SURVEY RESEARCH

    Directory of Open Access Journals (Sweden)

    Barbara Kiełbasa

    2016-03-01

    Full Text Available The purpose of the study was to identify driving and limiting factors of farm management in a region of fragmented agriculture. The paper presents the results of the research conducted in the South-Eastern Poland (Macroregion of Małopolska and Pogórze. The survey was conducted in 2014 in the farms managed by young farmers, i.e. the benefi ciaries of the measure “Setting up of young farmers” from the RDP 2007–2013, with the use of a survey method with a questionnaire interview. The research was empirical, and its main goal was to present a case study of the farm management by young farmers in terms of specifi c management barriers. The results of the studies pointed to the fragmented agrarian structure as the one of the biggest barriers of the eff ective farm management. The young farmers pointed that fragmented agrarian structure signifi cantly impedes the purchase or lease of agricultural land, and the farm development in the same way. The survey pointed to the factors that contribute to the young farmers: the entrepreneurial attitude, activity and creativity, training, the management knowledge and better access to the Common Agricultural Policy instruments.

  5. Innovative Operations Measures and Nutritional Support for Mass Endurance Events.

    Science.gov (United States)

    Chiampas, George T; Goyal, Anita V

    2015-11-01

    Endurance and sporting events have increased in popularity and participation in recent years worldwide, and with this comes the need for medical directors to apply innovative operational strategies and nutritional support to meet such demands. Mass endurance events include sports such as cycling and running half, full and ultra-marathons with over 1000 participants. Athletes, trainers and health care providers can all agree that both participant outcomes and safety are of the utmost importance for any race or sporting event. While demand has increased, there is relatively less published guidance in this area of sports medicine. This review addresses public safety, operational systems, nutritional support and provision of medical care at endurance events. Significant medical conditions in endurance sports include heat illness, hyponatraemia and cardiac incidents. These conditions can differ from those typically encountered by clinicians or in the setting of low-endurance sports, and best practices in their management are discussed. Hydration and nutrition are critical in preventing these and other race-related morbidities, as they can impact both performance and medical outcomes on race day. Finally, the command and communication structures of an organized endurance event are vital to its safety and success, and such strategies and concepts are reviewed for implementation. The nature of endurance events increasingly relies on medical leaders to balance safety and prevention of morbidity while trying to help optimize athlete performance.

  6. Long-term tolerability of PRRT in 807 patients with neuroendocrine tumours: the value and limitations of clinical factors

    Energy Technology Data Exchange (ETDEWEB)

    Bodei, Lisa; Grana, Chiara M. [European Institute of Oncology, Division of Nuclear Medicine, Milan (Italy); Kidd, Mark; Drozdov, Ignat; Lepensky, Christopher; Modlin, Irvin M. [Yale School of Medicine, Department of Surgery, New Haven, CT (United States); Paganelli, Giovanni [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Nuclear Medicine and Radiometabolic Units, Meldola (Italy); Cremonesi, Marta [European Institute of Oncology, Division of Medical Physics, Milan (Italy); Kwekkeboom, Dik J.; Krenning, Eric P. [Erasmus Medical Center, Department of Nuclear Medicine, Rotterdam (Netherlands); Baum, Richard P. [Zentralklinik Bad Berka, Theranostics Center for Molecular Radiotheraphy and Molecular Imaging, Bad Berka (Germany)

    2015-01-15

    9 months, p = 0.01) were relevant. Acute leukaemia occurred in 1.1 % of patients (modelled by the clinical data in 18 %, p < 0.0001). Identified risk factors provide a limited (<30 %) risk estimate even with target tissue dosimetry. These data strongly suggest the existence of unidentified individual susceptibilities to radiation-associated disease. (orig.)

  7. The Effect of Acute Sub-Maximal Endurance Exercise on Serum Angiogenic Indices in Sedentary Men

    Directory of Open Access Journals (Sweden)

    Kamal Ranjbar

    2014-06-01

    Full Text Available Background: Endurance training increases capillary density of skeletal muscle, but the molecular mechanism of this process is not yet clear. Therefore, the purpose of this study was to investigate the effect of acute sub maximal endurance exercise on serum levels of vascular endothelial growth factor (VEGF and matrix metaloproteinases 2 and 9 (MMP-2 and MMP-9 in sedentary men. Materials and Methods: Twelve healthy men (22.37±2.30 years, BMI=23.16 ±2.61 kg/mP 2 P participated in this study. Subjects exercised for 1h at 70% of VOR2R max, 3 days after the VOR2R max determination. Antecubital vein blood was collected at rest, immediately and 2h after the exercise. Serum VEGF, MMP-2 and MMP-9 were measured by ELISA methods5T. Results: Serum levels of VEGF and MMP-2 decreased immediately after the exercise. 2 hours after the exercise, serum levels of VEGF remained at a lower level but serum MMP-2 returned to its basal level. Also, serum levels of MMP-9 did not change significantly in response to exercise5T. Conclusion: Acute sub-maximal endurance exercise decreased the main factors involved in development of capillary density in sedentary men. This might to due to the fact that, sub maximal exercise could not provide the two main stimulating factors of angiogenesis, i.e. Shear stress and hypoxia. It could also be explained by the fact that the mechanism of development of capillary network following regular endurance training is different from that following an acute exercise5T.5T

  8. Increased risk of atrial fibrillation among elderly Norwegian men with a history of long-term endurance sport practice.

    Science.gov (United States)

    Myrstad, M; Løchen, M-L; Graff-Iversen, S; Gulsvik, A K; Thelle, D S; Stigum, H; Ranhoff, A H

    2014-08-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia. The prevalence increases with increasing age. In middle-aged men, endurance sport practice is associated with increased risk of AF but there are few studies among elderly people. The aim of this study was to investigate the role of long-term endurance sport practice as a risk factor for AF in elderly men. A cross-sectional study compared 509 men aged 65-90 years who participated in a long-distance cross-country ski race with 1768 men aged 65-87 years from the general population. Long-term endurance sport practice was the main exposure. Self-reported AF and covariates were assessed by questionnaires. Risk differences (RDs) for AF were estimated by using a linear regression model. After multivariable adjustment, a history of endurance sport practice gave an added risk for AF of 6.0 percent points (pp) (95% confidence interval 0.8-11.1). Light and moderate leisure-time physical activity during the last 12 months reduced the risk with 3.7 and 4.3 pp, respectively, but the RDs were not statistically significant. This study suggests that elderly men with a history of long-term endurance sport practice have an increased risk of AF compared with elderly men in the general population.

  9. Endurance Exercise Ability in the Horse: A Trait with Complex Polygenic Determinism.

    Science.gov (United States)

    Ricard, Anne; Robert, Céline; Blouin, Christine; Baste, Fanny; Torquet, Gwendoline; Morgenthaler, Caroline; Rivière, Julie; Mach, Nuria; Mata, Xavier; Schibler, Laurent; Barrey, Eric

    2017-01-01

    Endurance horses are able to run at more than 20 km/h for 160 km (in bouts of 30-40 km). This level of performance is based on intense aerobic metabolism, effective body heat dissipation and the ability to endure painful exercise. The known heritabilities of endurance performance and exercise-related physiological traits in Arabian horses suggest that adaptation to extreme endurance exercise is influenced by genetic factors. The objective of the present genome-wide association study (GWAS) was to identify single nucleotide polymorphisms (SNPs) related to endurance racing performance in 597 Arabian horses. The performance traits studied were the total race distance, average race speed and finishing status (qualified, eliminated or retired). We used three mixed models that included a fixed allele or genotype effect and a random, polygenic effect. Quantile-quantile plots were acceptable, and the regression coefficients for actual vs. expected log10p-values ranged from 0.865 to 1.055. The GWAS revealed five significant quantitative trait loci (QTL) corresponding to 6 SNPs on chromosomes 6, 1, 7, 16, and 29 (two SNPs) with corrected p-values from 1.7 × 10(-6) to 1.8 × 10(-5). Annotation of these 5 QTL revealed two genes: sortilin-related VPS10-domain-containing receptor 3 (SORCS3) on chromosome 1 is involved in protein trafficking, and solute carrier family 39 member 12 (SLC39A12) on chromosome 29 is active in zinc transport and cell homeostasis. These two coding genes could be involved in neuronal tissues (CNS). The other QTL on chromosomes 6, 7, and 16 may be involved in the regulation of the gene expression through non-coding RNAs, CpG islands and transcription factor binding sites. On chromosome 6, a new candidate equine long non-coding RNA (KCNQ1OT1 ortholog: opposite antisense transcript 1 of potassium voltage-gated channel subfamily Q member 1 gene) was predicted in silico and validated by RT-qPCR in primary cultures of equine myoblasts and fibroblasts. This

  10. Endurance Exercise Ability in the Horse: A Trait with Complex Polygenic Determinism

    Directory of Open Access Journals (Sweden)

    Anne Ricard

    2017-06-01

    Full Text Available Endurance horses are able to run at more than 20 km/h for 160 km (in bouts of 30–40 km. This level of performance is based on intense aerobic metabolism, effective body heat dissipation and the ability to endure painful exercise. The known heritabilities of endurance performance and exercise-related physiological traits in Arabian horses suggest that adaptation to extreme endurance exercise is influenced by genetic factors. The objective of the present genome-wide association study (GWAS was to identify single nucleotide polymorphisms (SNPs related to endurance racing performance in 597 Arabian horses. The performance traits studied were the total race distance, average race speed and finishing status (qualified, eliminated or retired. We used three mixed models that included a fixed allele or genotype effect and a random, polygenic effect. Quantile-quantile plots were acceptable, and the regression coefficients for actual vs. expected log10p-values ranged from 0.865 to 1.055. The GWAS revealed five significant quantitative trait loci (QTL corresponding to 6 SNPs on chromosomes 6, 1, 7, 16, and 29 (two SNPs with corrected p-values from 1.7 × 10−6 to 1.8 × 10−5. Annotation of these 5 QTL revealed two genes: sortilin-related VPS10-domain-containing receptor 3 (SORCS3 on chromosome 1 is involved in protein trafficking, and solute carrier family 39 member 12 (SLC39A12 on chromosome 29 is active in zinc transport and cell homeostasis. These two coding genes could be involved in neuronal tissues (CNS. The other QTL on chromosomes 6, 7, and 16 may be involved in the regulation of the gene expression through non-coding RNAs, CpG islands and transcription factor binding sites. On chromosome 6, a new candidate equine long non-coding RNA (KCNQ1OT1 ortholog: opposite antisense transcript 1 of potassium voltage-gated channel subfamily Q member 1 gene was predicted in silico and validated by RT-qPCR in primary cultures of equine myoblasts and

  11. Endurance Exercise Ability in the Horse: A Trait with Complex Polygenic Determinism

    Science.gov (United States)

    Ricard, Anne; Robert, Céline; Blouin, Christine; Baste, Fanny; Torquet, Gwendoline; Morgenthaler, Caroline; Rivière, Julie; Mach, Nuria; Mata, Xavier; Schibler, Laurent; Barrey, Eric

    2017-01-01

    Endurance horses are able to run at more than 20 km/h for 160 km (in bouts of 30–40 km). This level of performance is based on intense aerobic metabolism, effective body heat dissipation and the ability to endure painful exercise. The known heritabilities of endurance performance and exercise-related physiological traits in Arabian horses suggest that adaptation to extreme endurance exercise is influenced by genetic factors. The objective of the present genome-wide association study (GWAS) was to identify single nucleotide polymorphisms (SNPs) related to endurance racing performance in 597 Arabian horses. The performance traits studied were the total race distance, average race speed and finishing status (qualified, eliminated or retired). We used three mixed models that included a fixed allele or genotype effect and a random, polygenic effect. Quantile-quantile plots were acceptable, and the regression coefficients for actual vs. expected log10 p-values ranged from 0.865 to 1.055. The GWAS revealed five significant quantitative trait loci (QTL) corresponding to 6 SNPs on chromosomes 6, 1, 7, 16, and 29 (two SNPs) with corrected p-values from 1.7 × 10−6 to 1.8 × 10−5. Annotation of these 5 QTL revealed two genes: sortilin-related VPS10-domain-containing receptor 3 (SORCS3) on chromosome 1 is involved in protein trafficking, and solute carrier family 39 member 12 (SLC39A12) on chromosome 29 is active in zinc transport and cell homeostasis. These two coding genes could be involved in neuronal tissues (CNS). The other QTL on chromosomes 6, 7, and 16 may be involved in the regulation of the gene expression through non-coding RNAs, CpG islands and transcription factor binding sites. On chromosome 6, a new candidate equine long non-coding RNA (KCNQ1OT1 ortholog: opposite antisense transcript 1 of potassium voltage-gated channel subfamily Q member 1 gene) was predicted in silico and validated by RT-qPCR in primary cultures of equine myoblasts and fibroblasts. This

  12. Hypoxic training methods for improving endurance exercise performance

    Directory of Open Access Journals (Sweden)

    Jacob A. Sinex

    2015-12-01

    Full Text Available Endurance athletic performance is highly related to a number of factors that can be altered through altitude and hypoxic training including increases in erythrocyte volume, maximal aerobic exercise capacity, capillary density, and economy. Physiological adaptations in response to acute and chronic exposure to hypoxic environments are well documented and range from short-term detrimental effects to longer-term adaptations that can improve performance at altitude and in sea-level competitions. Many altitude and hypoxic training protocols have been developed, employing various combinations of living and training at sea-level, low, moderate, and high altitudes and utilizing natural and artificial altitudes, with varying degrees of effectiveness. Several factors have been identified that are associated with individual responses to hypoxic training, and techniques for identifying those athletes most likely to benefit from hypoxic training continue to be investigated. Exposure to sufficiently high altitude (2000–3000 m for more than 12 h/day, while training at lower altitudes, for a minimum of 21 days is recommended. Timing of altitude training related to competition remains under debate, although general recommendations can be considered.

  13. Satellite cell response to erythropoietin treatment and endurance training in healthy young men

    DEFF Research Database (Denmark)

    Hoedt, Andrea; Christensen, Britt; Nellemann, Birgitte

    2016-01-01

    KEY POINT: Erythropoietin (Epo) treatment may induce myogenic differentiation factor (MyoD) expression and prevent apoptosis in satellite cells (SCs) in murine and in vitro models. Endurance training stimulates SC proliferation in vivo in murine and human skeletal muscle. In the present study, we...... show, in human skeletal muscle, that treatment with an Epo-stimulating agent (darbepoetin-α) in vivo increases the content of MyoD(+) SCs in healthy young men. Moreover, we report that Epo receptor mRNA is expressed in adult human SCs, suggesting that Epo may directly target SCs through ligand......-term Epo treatment during disease conditions involving anaemia may impact SCs and warrants further investigation. Satellite cell (SC) proliferation is observed following erythropoitin treatment in vitro in murine myoblasts and endurance training in vivo in human skeletal muscle. The present study aimed...

  14. Endurance characteristics of phase change memory cells

    Science.gov (United States)

    Ruru, Huo; Daolin, Cai; Chen, Bomy; Yifeng, Chen; Yuchan, Wang; Yueqing, Wang; Hongyang, Wei; Qing, Wang; Yangyang, Xia; Dan, Gao; Zhitang, Song

    2016-05-01

    The endurance characteristics of phase change memory are studied. With operational cycles, the resistances of reset and set states gradually change to the opposite direction. What is more, the operational conditions that are needed are also discussed. The failure and the changes are concerned with the compositional change of the phase change material. An abnormal phenomenon that the threshold voltage decreases slightly at first and then increases is observed, which is due to the coaction of interface contact and growing active volume size changing. Project supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDA09020402), the National Key Basic Research Program of China (Nos. 2013CBA01900, 2010CB934300, 2011CBA00607, 2011CB932804), the National Integrate Circuit Research Program of China (No. 2009ZX02023-003), the National Natural Science Foundation of China (No. 61176122, 61106001, 61261160500, 61376006), and the Science and Technology Council of Shanghai (Nos. 12nm0503701, 13DZ2295700, 12QA1403900, 13ZR1447200, 14ZR1447500).

  15. INNOVATIVE METHODS OF DEVELOPMENT OF ENDURANCE

    Directory of Open Access Journals (Sweden)

    R. M. Cherkesov

    2016-01-01

    Full Text Available Currently taking place in the countries sociopolitical and socio-economic changes require corresponding changes in the part of departmental vocational training. Physical preparation of employees of law enforcement bodies of the Russian Federation of affairs is one of the areas in need of a thorough modification. With the growing volume and complexity of problems solved by the system of internal affairs bodies, including the configuration of highquality modern crime make it necessary to increase the physical training officer. To maintain law and order and successfully confront crime, the police officer should equally have both legal skills and a decent physical training. This principle of operation is to become a professional duty of a police officer. The article tells about the basic methods of general and special endurance, as well as on innovative developments in this field. Use of physical force has become commonplace in the everyday life of law enforcement officers. This entails the risk of serious consequences, in some cases; threaten the health and life of humans. Therefore, of particular importance are the problem of ensuring the rights of citizens, the rule of law in the activities of departments of internal affairs bodies.

  16. Multicistronic lentiviral vectors containing the FMDV 2A cleavage factor demonstrate robust expression of encoded genes at limiting MOI

    Directory of Open Access Journals (Sweden)

    Margison Geoffrey P

    2006-03-01

    Full Text Available Abstract Background A number of gene therapy applications would benefit from vectors capable of expressing multiple genes. In this study we explored the feasibility and efficiency of expressing two or three transgenes in HIV-1 based lentiviral vector. Bicistronic and tricistronic self-inactivating lentiviral vectors were constructed employing the internal ribosomal entry site (IRES sequence of encephalomyocarditis virus (EMCV and/or foot-and-mouth disease virus (FMDV cleavage factor 2A. We employed enhanced green fluorescent protein (eGFP, O6-methylguanine-DNA-methyltransferase (MGMT, and homeobox transcription factor HOXB4 as model genes and their expression was detected by appropriate methods including fluorescence microscopy, flow cytometry, immunocytochemistry, biochemical assay, and western blotting. Results All the multigene vectors produced high titer virus and were able to simultaneously express two or three transgenes in transduced cells. However, the level of expression of individual transgenes varied depending on: the transgene itself; its position within the construct; the total number of transgenes expressed; the strategy used for multigene expression and the average copy number of pro-viral insertions. Notably, at limiting MOI, the expression of eGFP in a bicistronic vector based on 2A was ~4 times greater than that of an IRES based vector. Conclusion The small and efficient 2A sequence can be used alone or in combination with an IRES for the construction of multicistronic lentiviral vectors which can express encoded transgenes at functionally relevant levels in cells containing an average of one pro-viral insert.

  17. Effects of endurance training in the leopard shark, Triakis semifasciata.

    Science.gov (United States)

    Gruber, S J; Dickson, K A

    1997-01-01

    This study is the first to examine the effects of endurance training in an elasmobranch fish. Twenty-four leopard sharks (Triakis semifasciata) were divided randomly into three groups. Eight sharks were killed immediately, eight were forced to swim continuously for 6 wk against a current of 35 cm s-1 (60%-65% of maximal sustainable swimming speed), and eight were held for 6 wk in a tank without induced current. There were no changes due to training in maximal sustainable speed, oxygen consumption rates, percentage of the myotome composed of red and white muscle fibers, blood oxygen-carrying capacity, liver mass, liver lipid, glycogen, and protein concentrations, white muscle protein content, heart ventricle mass, or the specific activities of the enzymes citrate synthase, pyruvate kinase, and lactate dehydrogenase in the heart ventricle. In red myotomal muscle, citrate synthase activity increased 17% as a result of training, but there was no change in muscle fiber diameter. The greatest effects occurred in white myotomal muscle, in which a 34% increase in fiber diameter and a 36% increase in the activities of citrate synthase and lactate dehydrogenase occurred as a result of training. The conditioned fish also had significantly higher growth rates. The observed effects within the myotomal muscle may reflect the higher growth rates of the trained leopard sharks, or they may be a specific response to the increased energetic demands of the training activity, indicating characteristics that limit swimming performance in leopard sharks.

  18. Sprint, agility, strength and endurance capacity in wheelchair basketball players

    National Research Council Canada - National Science Library

    Yanci, J; Granados, C; Otero, M; Badiola, A; Olasagasti, J; Bidaurrazaga-Letona, I; Iturricastillo, A; Gil, Sm

    ...; and secondly, to analyse the physical characteristics measured by sprint, agility, strength and endurance field tests in wheelchair basketball (WB) players. 16 WB players (33.06 ± 7.36 years, 71.89...

  19. Bone health in endurance athletes: runners, cyclists, and swimmers.

    Science.gov (United States)

    Scofield, Kirk L; Hecht, Suzanne

    2012-01-01

    Weight-bearing exercise has been recognized widely to be beneficial for long-term bone health. However inherent differences in bone-loading characteristics and energy expenditure during participation in endurance sports place many endurance athletes at a relative disadvantage with regard to bone health compared with other athletes. Adolescents and adults who participate in endurance sports, such as running, and non-weight-bearing sports, such as biking and swimming, often have lower bone mineral density (BMD) than athletes participating in ball and power sports, and sometimes their BMD is lower than their inactive peers. Low BMD increases the risk of stress and fragility fractures, both while an athlete is actively competing and later in life. This article reviews the variable effects of distance running, cycling, swimming, and triathlons on bone health; the evaluation of stress and fragility fractures; and the diagnosis, management, and prevention of low BMD in endurance athletes.

  20. Reduced neuromuscular performance in amenorrheic elite endurance athletes

    DEFF Research Database (Denmark)

    Tornberg, Åsa B; Melin, Anna; Manderson Koivula, Fiona

    2017-01-01

    INTRODUCTION: Secondary functional hypothalamic amenorrhea (SFHA) is common among female athletes, especially in weight-sensitive sports. The aim of this study was to investigate the link between SFHA and neuromuscular performance in elite endurance athletes. METHODS: Sixteen eumenorrheic (EUM...

  1. Endurance training and GH administration in elderly women

    DEFF Research Database (Denmark)

    Lange, K H; Lorentsen, J; Isaksson, F;

    2001-01-01

    In the present study, the effect of endurance training alone and endurance training combined with recombinant human growth hormone (rhGH) administration on subcutaneous abdominal adipose tissue lipolysis was investigated. Sixteen healthy women [age 75 +/- 2 yr (mean +/- SE)] underwent a 12-wk...... endurance training program on a cycle ergometer. rhGH was administered in a randomized, double-blinded, placebo-controlled design in addition to the training program. Subcutaneous abdominal adipose tissue lipolysis was estimated by means of microdialysis combined with measurements of subcutaneous abdominal...... and after completion of the training program. Similarly, no effect on subcutaneous abdominal adipose tissue lipolysis was observed when combining endurance training with rhGH administration. However, in both the placebo and the GH groups, fat oxidation was significantly increased during exercise performed...

  2. Tenax extraction for exploring rate-limiting factors in methyl-β-cyclodextrin enhanced anaerobic biodegradation of PAHs under denitrifying conditions in a red paddy soil

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Mingming, E-mail: sunmingming@njau.edu.cn [Soil Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Key Laboratory of Soil Environmental and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Ye, Mao [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Hu, Feng, E-mail: fenghu@njau.edu.cn [Soil Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Li, Huixin [Soil Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Teng, Ying [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Luo, Yongming [Yantai Institute of Costal Zone Research, Chinese Academy of Sciences, Yantai 264003 (China); Jiang, Xin [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Kengara, Fredrick Orori [Department of Chemistry, Maseno University, Private Bag, Maseno 40105 (Kenya)

    2014-01-15

    Highlights: • Enhanced anaerobic bioremediation of a red paddy soil polluted with PAHs. • 1% (w/w) methyl-β-cyclodextrin (MCD) and 20 mM nitrate addition acted as solubility-enhancing agent and electron acceptor respectively. • Tenax extraction and a first-three-compartment modeling were applicable to explore the rate-limiting factors in the biodegradation. • Lack of PAH-degraders hindered biodegradation in control and MCD addition treatments. • Inadequate bioaccessible PAHs was vital rate-limiting factor in nitrate addition treatments. -- Abstract: The effectiveness of anaerobic bioremediation systems for PAH-contaminated soil may be constrained by low contaminants bioaccessibility due to limited aqueous solubility and lack of suitable electron acceptors. Information on what is the rate-limiting factor in bioremediation process is of vital importance in the decision in what measures can be taken to assist the biodegradation efficacy. In the present study, four different microcosms were set to study the effect of methyl-β-cyclodextrin (MCD) and nitrate addition (N) on PAHs biodegradation under anaerobic conditions in a red paddy soil. Meanwhile, sequential Tenax extraction combined with a first-three-compartment model was employed to evaluate the rate-limiting factors in MCD enhanced anaerobic biodegradation of PAHs. Microcosms with both 1% (w/w) MCD and 20 mM N addition produced maximum biodegradation of total PAHs of up to 61.7%. It appears rate-limiting factors vary with microcosms: low activity of degrading microorganisms is the vital rate-limiting factor for control and MCD addition treatments (CK and M treatments); and lack of bioaccessible PAHs is the main rate-limiting factor for nitrate addition treatments (N and MN treatments). These results have practical implications for site risk assessment and cleanup strategies.

  3. Physical fitness differences of students with different cardiorespiratory endurance levels

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    Stojanović Darko

    2016-01-01

    Full Text Available In order to determine physical fitness differences in students with different cardiorespiratory endurance levels, a study was conducted on a sample of students of the Faculty of Sport and Physical Education at the University of Nis. The sample was divided into two subsamples, where the first subsample comprised 27 female students and the other 35 male students. Physical fitness was assessed using eight tests from the Eurofit battery of tests: the single-leg balance test - for the assessment of general balance, plate tapping - for the assessment of speed of movement, sit-and-reach - for the assessment of flexibility, the standing broad jump - for the assessment of explosive strength, the handgrip test - for the assessment of static strength, sit-ups - for the assessment of repetitive trunk strength, the bent arm hang - for the assessment of muscular endurance and the 10x5 meter shuttle run - for the assessment of the speed/agility. Cardiorespiratory endurance was estimated with the aid of 20 m endurance shuttle-run test. Based on the level of cardiorespiratory endurance, the participants in each subsample, were divided into three groups using a cluster analysis: high (VKRI, average (PKRI and low level (NKRI. The physical fitness differences of students with different cardiorespiratory endurance levels were calculated using the one-way analysis of variance. The results showed that there were no differences in physical fitness of students with different cardiorespiratory endurance levels. Based on the results it can be concluded that the level of cardiorespiratory endurance does not affect the components of physical fitness among students of both sexes.

  4. Carbon baseline as limiting factor in managing environmental sound activities in peatland for reducing greenhouse gas emission

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    BAMBANG HERO SAHARJO

    2011-07-01

    Full Text Available Saharjo BH (2011 Carbon baseline as limiting factor in managing environmental sound activities in peatland for reducing greenhouse gas emission. Biodiversitas 12: 182-186. The total carbon stock in Indonesia was estimated to be around 44.5 Gt or about 53.1% of the total carbon stock in tropical areas. Over 1990-2002, it was estimated that around 3.5 Gt of carbon was released in Sumatra and about 0.81-2.56 Gt was released in Central Kalimantan due to the 1997 fire alone. It was recognized that deforestation, high exploitation of peat and peat fire were behind the huge emissions of Greenhouse Gases in Indonesia. Results of a research conducted in Central Kalimantan peatland, showed that the total carbon stock at logged over area was estimated around 413.972 t ha-1 (0-30 cm depth of peat and at burnt area was 411.349 t ha-1 (0-30 cm depth of peat. Meanwhile it had been well recognized that most of opened peatlands had been occupied by Acacia crassicarpa and oil palms. Research carried out in East Kalimantan showed that the carbon stock of 25 years old oil palm planted on mineral soil was about 180 t ha-1, which is less than that of carbon stock produced by peatland clearance. This indicated that although plants occupied peatland, high Greenhouse Gas emissions were still produced, meaning that global climate change would continue and created high risk impacts.

  5. Eop1 from a Rubus strain of Erwinia amylovora functions as a host-range limiting factor.

    Science.gov (United States)

    Asselin, J E; Bonasera, J M; Kim, J F; Oh, C-S; Beer, S V

    2011-08-01

    Strains of Erwinia amylovora, the bacterium causing the disease fire blight of rosaceous plants, are separated into two groups based on host range: Spiraeoideae and Rubus strains. Spiraeoideae strains have wide host ranges, infecting plants in many rosaceous genera, including apple and pear. In the field, Rubus strains infect the genus Rubus exclusively, which includes raspberry and blackberry. Based on comparisons of limited sequence data from a Rubus and a Spiraeoideae strain, the gene eop1 was identified as unusually divergent, and it was selected as a possible host specificity factor. To test this, eop1 genes from a Rubus strain and a Spiraeoideae strain were cloned and mutated. Expression of the Rubus-strain eop1 reduced the virulence of E. amylovora in immature pear fruit and in apple shoots. Sequencing the orfA-eop1 regions of several strains of E. amylovora confirmed that forms of eop1 are conserved among strains with similar host ranges. This work provides evidence that eop1 from a Rubus-specific strain can function as a determinant of host specificity in E. amylovora.

  6. Prevalence and Risk Factors Associated with Precancerous Cervical Cancer Lesions among HIV-Infected Women in Resource-Limited Settings

    Directory of Open Access Journals (Sweden)

    Peter Memiah

    2012-01-01

    Full Text Available Objective. To assess the prevalence and identified associated risk factors for precancerous cervical cancer lesions among HIV-infected women in resource-limited settings in Kenya. Methods. HIV-infected women attending the ART clinic at the Nazareth Hospital ART clinic between June 2009 and September 2010. Multivariate logistic regression model with odds ratios and 95% confidence intervals (CI were estimated after controlling for important covariates. Result. A total of 715 women were screened for cervical cancer. The median age of the participants was 40 years (range 18–69 years. The prevalence of precancerous lesions (CINI, CINII, CIN III, ICC was 191 (26.7%. After controlling for other variables in logistic regression analysis, cervical precancerous lesions were associated with not being on ART therapy; whereby non-ART were 2.21 times more likely to have precancerous lesions than ART patients [(aOR=2.21, 95% CI (1.28–3.83]. Conclusion. The prevalence of precancerous cervical lesions was lower than other similar settings. It is recommended that cancer screening of HIV-infected women should be an established practice. Availability and accessibility of these services can be done through their integration into HIV. Prompt initiation of HAART through an early enrollment into care has an impact on reducing the prevalence and progression of cervical precancerous lesions.

  7. Does medium chain triglyceride play an ergogenic role in endurance exercise performance?

    Directory of Open Access Journals (Sweden)

    Gomes Rodrigo Vitasovic

    2003-01-01

    Full Text Available Because of the medium chain triglycerides (MCT specific physical and chemical properties, they have been used over the last 40 years in enteral and parenteral nutrition. Results from clinical practice lead some researchers in the early 80's to use them for ergogenics purposes. The hypothesis was based on the relationship between the oxidation rates of carbohydrate and fat. The increase in fat oxidation would promote glycogen sparing effect, and therefore, delay the time to exhaustion. The aim of the present paper is to review the effects of MCT supplementation upon endurance exercise performance. Most of the studies failed to prove the ergogenic effect of MCT. A few studies that showed the ergogenic effect of MCT administration used alternative experimental designs, such as high MCT dose (above from the previous established limit or infusion. The chronic use of MCT by athletes is new and few studies have been done in this matter. These few studies showed controversial results. There is a strong tendency in the literature that MCT is not a viable strategy to increase performance during endurance exercise. The aim of this study is to discuss the effects of MCT use on endurance exercise.

  8. mDurance: A Novel Mobile Health System to Support Trunk Endurance Assessment

    Directory of Open Access Journals (Sweden)

    Oresti Banos

    2015-06-01

    Full Text Available Low back pain is the most prevalent musculoskeletal condition. This disorder constitutes one of the most common causes of disability worldwide, and as a result, it has a severe socioeconomic impact. Endurance tests are normally considered in low back pain rehabilitation practice to assess the muscle status. However, traditional procedures to evaluate these tests suffer from practical limitations, which potentially lead to inaccurate diagnoses. The use of digital technologies is considered here to facilitate the task of the expert and to increase the reliability and interpretability of the endurance tests. This work presents mDurance, a novel mobile health system aimed at supporting specialists in the functional assessment of trunk endurance by using wearable and mobile devices. The system employs a wearable inertial sensor to track the patient trunk posture, while portable electromyography sensors are used to seamlessly measure the electrical activity produced by the trunk muscles. The information registered by the sensors is processed and managed by a mobile application that facilitates the expert’s normal routine, while reducing the impact of human errors and expediting the analysis of the test results. In order to show the potential of the mDurance system, a case study has been conducted. The results of this study prove the reliability of mDurance and further demonstrate that practitioners are certainly interested in the regular use of a system of this nature.

  9. Radiation endurance of piezoelectric ultrasonic transducers--a review.

    Science.gov (United States)

    Sinclair, A N; Chertov, A M

    2015-03-01

    A literature survey is presented on the radiation endurance of piezoelectric ultrasonic transducer components and complete transducer assemblies, as functions of cumulative gamma dose and neutron fluence. The most extensive data on this topic has been acquired in CANDU electrical generating stations, which use piezoelectric ultrasonic transducers manufactured commercially with minor accommodation for high radiation fields. They have been found to be reliable for cumulative gamma doses of up to approximately 2 MegaGrays; a brief summary is made of the associated accommodations required to the transducer design, and the ultimate expected failure modes. Outside of the CANDU experience, endurance data have been acquired under a diverse spectrum of operating conditions; this can impede a direct comparison of the information from different sources. Much of this data is associated with transducers immersed in liquid metal coolants associated with advanced reactor designs. Significant modifications to conventional designs have led to the availability of custom transducers that can endure well over 100 MegaGrays of cumulative gamma dose. Published data on transducer endurance against neutron fluence are reviewed, but are either insufficient, or were reported with inadequate description of test conditions, to make general conclusions on transducer endurance with high confidence. Several test projects are planned or are already underway by major laboratories and research consortia to augment the store of transducer endurance data with respect to both gamma and neutron radiation.

  10. Tenax extraction for exploring rate-limiting factors in methyl-β-cyclodextrin enhanced anaerobic biodegradation of PAHs under denitrifying conditions in a red paddy soil.

    Science.gov (United States)

    Sun, Mingming; Ye, Mao; Hu, Feng; Li, Huixin; Teng, Ying; Luo, Yongming; Jiang, Xin; Kengara, Fredrick Orori

    2014-01-15

    The effectiveness of anaerobic bioremediation systems for PAH-contaminated soil may be constrained by low contaminants bioaccessibility due to limited aqueous solubility and lack of suitable electron acceptors. Information on what is the rate-limiting factor in bioremediation process is of vital importance in the decision in what measures can be taken to assist the biodegradation efficacy. In the present study, four different microcosms were set to study the effect of methyl-β-cyclodextrin (MCD) and nitrate addition (N) on PAHs biodegradation under anaerobic conditions in a red paddy soil. Meanwhile, sequential Tenax extraction combined with a first-three-compartment model was employed to evaluate the rate-limiting factors in MCD enhanced anaerobic biodegradation of PAHs. Microcosms with both 1% (w/w) MCD and 20mM N addition produced maximum biodegradation of total PAHs of up to 61.7%. It appears rate-limiting factors vary with microcosms: low activity of degrading microorganisms is the vital rate-limiting factor for control and MCD addition treatments (CK and M treatments); and lack of bioaccessible PAHs is the main rate-limiting factor for nitrate addition treatments (N and MN treatments). These results have practical implications for site risk assessment and cleanup strategies.

  11. Increased fatigue resistance of respiratory muscles during exercise after respiratory muscle endurance training.

    Science.gov (United States)

    Verges, Samuel; Lenherr, Oliver; Haner, Andrea C; Schulz, Christian; Spengler, Christina M

    2007-03-01

    Respiratory muscle fatigue develops during exhaustive exercise and can limit exercise performance. Respiratory muscle training, in turn, can increase exercise performance. We investigated whether respiratory muscle endurance training (RMT) reduces exercise-induced inspiratory and expiratory muscle fatigue. Twenty-one healthy, male volunteers performed twenty 30-min sessions of either normocapnic hyperpnoea (n = 13) or sham training (CON, n = 8) over 4-5 wk. Before and after training, subjects performed a constant-load cycling test at 85% maximal power output to exhaustion (PRE(EXH), POST(EXH)). A further posttraining test was stopped at the pretraining duration (POST(ISO)) i.e., isotime. Before and after cycling, transdiaphragmatic pressure was measured during cervical magnetic stimulation to assess diaphragm contractility, and gastric pressure was measured during thoracic magnetic stimulation to assess abdominal muscle contractility. Overall, RMT did not reduce respiratory muscle fatigue. However, in subjects who developed >10% of diaphragm or abdominal muscle fatigue in PRE(EXH), fatigue was significantly reduced after RMT in POST(ISO) (inspiratory: -17 +/- 6% vs. -9 +/- 10%, P = 0.038, n = 9; abdominal: -19 +/- 10% vs. -11 +/- 11%, P = 0.038, n = 9), while sham training had no significant effect. Similarly, cycling endurance in POST(EXH) did not improve after RMT (P = 0.071), while a significant improvement was seen in the subgroup with >10% of diaphragm fatigue after PRE(EXH) (P = 0.017), but not in the sham training group (P = 0.674). However, changes in cycling endurance did not correlate with changes in respiratory muscle fatigue. In conclusion, RMT decreased the development of respiratory muscle fatigue during intensive exercise, but this change did not seem to improve cycling endurance.

  12. The enduring impact of violence against children.

    Science.gov (United States)

    Hillis, Susan D; Mercy, James A; Saul, Janet R

    2017-04-01

    More than one billion children - half of all children in the world - are exposed to violence every year. The violence children are exposed to includes both direct experiences of physical, sexual, and emotional abuse, as well as indirectly witnessing violence in their homes, schools, and communities. What these various forms of violence share, based on a review of the literature, is their enduring potential for life-long consequences. These consequences include increases in the risks of injury, HIV, sexually transmitted infections, mental health problems, reproductive health problems, and non-communicable diseases, including cardiovascular disease, cancer, chronic lung disease, and diabetes. Studies addressing biologic underpinnings of such consequences demonstrate that violence-associated toxic stress may cause damage to the nervous, endocrine, circulatory, musculo-skeletal, reproductive, respiratory, and immune systems. Furthermore, rigorous economic evaluations suggest that costs associated with the consequences of violence against children exceed $120 billion in the U.S. and account for up to 3.5% of the GDP in sub-regions of East Asia. The expanding literature confirming the mechanisms of consequences and the associated costs of violence against children has been accompanied by growing evidence on effective approaches to prevention. Moreover, the expanding evidence on prevention has been accompanied by a growing determination on the part of global leaders to accelerate action. Thus, as part of the Post-2015 Sustainable Development agenda, the UN has issued a call-to-action: to eliminate violence against children. This unprecedented UN call may foster new investments, to fuel new progress for protecting children around the world from violence and its preventable consequences.

  13. Waiting Endurance Time Estimation of Electric Two-Wheelers at Signalized Intersections

    Directory of Open Access Journals (Sweden)

    Mei Huan

    2014-01-01

    Full Text Available The paper proposed a model for estimating waiting endurance times of electric two-wheelers at signalized intersections using survival analysis method. Waiting duration times were collected by video cameras and they were assigned as censored and uncensored data to distinguish between normal crossing and red-light running behavior. A Cox proportional hazard model was introduced, and variables revealing personal characteristics and traffic conditions were defined as covariates to describe the effects of internal and external factors. Empirical results show that riders do not want to wait too long to cross intersections. As signal waiting time increases, electric two-wheelers get impatient and violate the traffic signal. There are 12.8% of electric two-wheelers with negligible wait time. 25.0% of electric two-wheelers are generally nonrisk takers who can obey the traffic rules after waiting for 100 seconds. Half of electric two-wheelers cannot endure 49.0 seconds or longer at red-light phase. Red phase time, motor vehicle volume, and conformity behavior have important effects on riders’ waiting times. Waiting endurance times would decrease with the longer red-phase time, the lower traffic volume, or the bigger number of other riders who run against the red light. The proposed model may be applicable in the design, management and control of signalized intersections in other developing cities.

  14. Pronounced effects of acute endurance exercise on gene expression in resting and exercising human skeletal muscle.

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    Milène Catoire

    Full Text Available Regular physical activity positively influences whole body energy metabolism and substrate handling in exercising muscle. While it is recognized that the effects of exercise extend beyond exercising muscle, it is unclear to what extent exercise impacts non-exercising muscles. Here we investigated the effects of an acute endurance exercise bouts on gene expression in exercising and non-exercising human muscle. To that end, 12 male subjects aged 44-56 performed one hour of one-legged cycling at 50% W(max. Muscle biopsies were taken from the exercising and non-exercising leg before and immediately after exercise and analyzed by microarray. One-legged cycling raised plasma lactate, free fatty acids, cortisol, noradrenalin, and adrenalin levels. Surprisingly, acute endurance exercise not only caused pronounced gene expression changes in exercising muscle but also in non-exercising muscle. In the exercising leg the three most highly induced genes were all part of the NR4A family. Remarkably, many genes induced in non-exercising muscle were PPAR targets or related to PPAR signalling, including PDK4, ANGPTL4 and SLC22A5. Pathway analysis confirmed this finding. In conclusion, our data indicate that acute endurance exercise elicits pronounced changes in gene expression in non-exercising muscle, which are likely mediated by changes in circulating factors such as free fatty acids. The study points to a major influence of exercise beyond the contracting muscle.

  15. Limit of detection and threshold for positivity of the Centers for Disease Control and Prevention assay for factor VIII inhibitors.

    Science.gov (United States)

    Miller, C H; Boylan, B; Shapiro, A D; Lentz, S R; Wicklund, B M

    2017-08-10

    Essentials Immunologic methods detect factor VIII (FVIII) antibodies in some inhibitor-negative specimens. Specimens were tested by modified Nijmegen-Bethesda assay (NBA) and fluorescence immunoassay. The NBA with preanalytical heat inactivation detects FVIII inhibitors down to 0.2 NBU. IgG4 frequency validates the established threshold for positivity of ≥ 0.5 NBU for this NBA. Background The Bethesda assay for measurement of factor VIII inhibitors called for quantification of positive inhibitors by using dilutions producing 25-75% residual activity (RA), corresponding to 0.4-2.0 Bethesda units, with the use of 'more sensitive methods' for samples with RA closer to 100% being recommended. The Nijmegen modification (Nijmegen-Bethesda assay [NBA]) changed the reagents used but not these calculations. Some specimens negative by the NBA have been shown to have FVIII antibodies detectable with sensitive immunologic methods. Objective To examine the performance at very low inhibitor titers of the Centers for Disease Control and Prevention (CDC)-modified NBA (CDC-NBA), which includes preanalytic heat inactivation to liberate bound anti-FVIII antibodies. Methods Specimens with known inhibitors were tested with the CDC-NBA. IgG4 anti-FVIII antibodies were measured by fluorescence immunoassay (FLI). Results Diluted inhibitors showed linearity below 0.4 Nijmegen-Bethesda units (NBU). With four statistical methods, the limit of detection of the CDC-NBA was determined to be 0.2 NBU. IgG4 anti-FVIII antibodies, which correlate most strongly with functional inhibitors, were present at rates above the background rate of healthy controls in specimens with titers ≥ 0.2 NBU and showed an increase in frequency from 14.3% at 0.4 NBU to 67% at the established threshold for positivity of 0.5 NBU. Conclusions The CDC-NBA can detect inhibitors down to 0.2 NBU. The FLI, which is more sensitive, demonstrates anti-FVIII IgG4 in some patients with negative (NBA, supporting the need for

  16. Endurance training prevents negative effects of the hypoxia mimetic dimethyloxalylglycine on cardiac and skeletal muscle function.

    Science.gov (United States)

    Favier, Francois B; Britto, Florian A; Ponçon, Benjamin; Begue, Gwenaelle; Chabi, Beatrice; Reboul, Cyril; Meyer, Gregory; Py, Guillaume

    2016-02-15

    Hypoxic preconditioning is a promising strategy to prevent hypoxia-induced damages to several tissues. This effect is related to prior stabilization of the hypoxia-inducible factor-1α via inhibition of the prolyl-hydroxylases (PHDs), which are responsible for its degradation under normoxia. Although PHD inhibition has been shown to increase endurance performance in rodents, potential side effects of such a therapy have not been explored. Here, we investigated the effects of 1 wk of dimethyloxalylglycine (DMOG) treatment (150 mg/kg) on exercise capacity, as well as on cardiac and skeletal muscle function in sedentary and endurance-trained rats. DMOG improved maximal aerobic velocity and endurance in both sedentary and trained rats. This effect was associated with an increase in red blood cells without significant alteration of skeletal muscle contractile properties. In sedentary rats, DMOG treatment resulted in enhanced left ventricle (LV) weight together with impairment in diastolic function, LV relaxation, and pulse pressure. Moreover, DMOG decreased maximal oxygen uptake (state 3) of isolated mitochondria from skeletal muscle. Importantly, endurance training reversed the negative effects of DMOG treatment on cardiac function and restored maximal mitochondrial oxygen uptake to the level of sedentary placebo-treated rats. In conclusion, we provide here evidence that the PHD inhibitor DMOG has detrimental influence on myocardial and mitochondrial function in healthy rats. However, one may suppose that the deleterious influence of PHD inhibition would be potentiated in patients with already poor physical condition. Therefore, the present results prompt us to take into consideration the potential side effects of PHD inhibitors when administrated to patients.

  17. Level of data quality from Health Management Information Systems in a resources limited setting and its associated factors, eastern Ethiopia

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    Kidist Teklegiorgis

    2016-04-01

    Full Text Available Background: A Health Information System (HIS is a system that integrates data collection, processing, reporting, and use of the information necessary for improving health service effectiveness and efficiency through better management at all levels of health services. Despite the credible use of HIS for evidence-based decision-making, countries with the highest burden of ill health and the most in need of accurate and timely data have the weakest HIS in the vast majority of world’s poorest countries. Although a Health Management Information System (HMIS forms a backbone for strong health systems, most developing countries still face a challenge in strengthening routine HIS. The main focus of this study was to assess the current HIS performance and identify factors affecting data quality in a resource-limited setting, such as Ethiopian health facilities.Methods: A cross-sectional study was conducted by using structured questionnaires in Dire Dawa Administration health facilities. All unit and/or department heads from all government health facilities were selected. The data was analysed using STATA version 11. Frequency and percentages were computed to present the descriptive findings. Association between variables was computed using binary logistic regression.Results: Over all data quality was found to be 75.3% in unit and/or departments. Trained staff to fill format, decision based on supervisor directives and department heads seek feedback were significantly associated with data quality and their magnitudes were (AOR = 2.253, 95% CI [1.082, 4.692], (AOR = 2.131, 95% CI [1.073, 4.233] and (AOR = 2.481, 95% CI [1.262, 4.876], respectively.Conclusion: Overall data quality was found to be below the national expectation level. Low data quality was found at health posts compared to health centres and hospitals. There was also a shortage of assigned HIS personnel, separate HIS offices, and assigned budgets for HIS across all units and/or departments.

  18. Factors limiting performance in a multitone intensity-discrimination task: disentangling non-optimal decision weights and increased internal noise.

    Directory of Open Access Journals (Sweden)

    Daniel Oberfeld

    Full Text Available To identify factors limiting performance in multitone intensity discrimination, we presented sequences of five pure tones alternating in level between loud (85 dB SPL and soft (30, 55, or 80 dB SPL. In the "overall-intensity task", listeners detected a level increment on all of the five tones. In the "masking task", the level increment was imposed only on the soft tones, rendering the soft tones targets and loud tones task-irrelevant maskers. Decision weights quantifying the importance of the five tone levels for the decision were estimated using methods of molecular psychophysics. Compatible with previous studies, listeners placed higher weights on the loud tones than on the soft tones in the overall-intensity condition. In the masking task, the decisions were systematically influenced by the to-be-ignored loud tones (maskers. Using a maximum-likelihood technique, we estimated the internal noise variance and tested whether the internal noise was higher in the alternating-level five-tone sequences than in sequences presenting only the soft or only the loud tones. For the overall-intensity task, we found no evidence for increased internal noise, but listeners applied suboptimal decision weights. These results are compatible with the hypothesis that the presence of the loud tones does not impair the precision of the representation of the intensity of the soft tones available at the decision stage, but that this information is not used in an optimal fashion due to a difficulty in attending to the soft tones. For the masking task, in some cases our data indicated an increase in internal noise. Additionally, listeners applied suboptimal decision weights. The maximum-likelihood analyses we developed should also be useful for other tasks or other sensory modalities.

  19. Limited efficacy of COX-2 inhibitors on nerve growth factor and metalloproteinases expressions in human synovial fibroblasts.

    Science.gov (United States)

    Yorifuji, Makiko; Sawaji, Yasunobu; Endo, Kenji; Kosaka, Taiichi; Yamamoto, Kengo

    2016-05-01

    Nerve growth factor (NGF) is associated with arthritic pain and metalloproteinases are implicated in collagen and aggrecan degradation. Although selective COX-2 inhibitors are recommended for the treatment of arthritic diseases, their effects on NGF and metalloproteinases remain unclear. This study investigated the regulations of NGF and metalloproteinases by selective COX-2 inhibitors in isolated human synovial cells. The isolated human synovial cells were stimulated with IL-1β in the presence of selective COX-2 inhibitors (NS-398 or celecoxib) with or without exogenous PGE2 or its receptor (EP1-4) agonists. The expressions of NGF, MMP-1, -3, -13, ADAMTS-4, and -5 were quantified by real-time PCR and their proteins were determined by Western blotting. The amount of PGE2 released was measured by enzyme-linked immunosorbent assay (ELISA). The IL-1β inductions of NGF and MMP-1 and MMP-13 were augmented by the COX-2 inhibitors, whereas the inductions of ADAMTS-4 and ADAMTS-5 were inhibited. These actions were reversed by supplementing PGE2 or the EP4 agonist exogenously. Our comprehensive analysis revealed that COX-2 inhibitors may be beneficial for suppressing aggrecan degradation and for reducing inflammatory pain by inhibiting PGE2 release, although they may have limited efficacy in suppressing collagen degradation and nerve growth. This study suggests the feedback roles of PGE2 in the negative regulation of NGF and MMP-1 and MMP-13 and the positive regulation of ADAMTS-4 and ADAMTS-5. Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  20. Blood Doping Improves Endurance and Heat Tolerance, Studies Say.

    Science.gov (United States)

    Duda, Marty

    1987-01-01

    Recent research on blood doping is reviewed, focusing on how the practice may help to determine what factors limit human performance, particularly regarding its potential benefit as an aid in thermal regulation. (CB)

  1. Noninvasive evaluation of the athletic heart: sprinters versus endurance runners.

    Science.gov (United States)

    Ikäheimo, M J; Palatsi, I J; Takkunen, J T

    1979-07-01

    To evaluate possible differences in the cardiac effects of different types of running training, 22 competing male runners--10 sprinters and 12 endurance runners--were studied with a physical examination, electrocardiography, chest X-ray film and echocardiography. Thirteen sedentary men served as control subjects. There were no differences between the athletic groups in physical findings. However, left ventricular hypertrophy in the electrocardiogram was more apparent in the endurance runners (P less than 0.05), whose relative heart size on chest X-ray examination was also greater than in the sprinters (P less than 0.02). On echocardiography the left ventricular end-diastolic volume was equally greater than normal in both groups of athletes (P less than 0.005), but in the endurance runners the percent chance of the minor axis diameter in systole was greater than in the sprinters or control subjects (P less than 0.02). Values for left ventricular wall thickness and mass were greater than normal in both groups of athletes but were higher in the endurance runners than in the sprinters (P less than 0.001). The left atrial diameter was apparently greater in the endurance runners than in the sprinters or control subjects (P less than 0.001), whereas that of the sprinters did not differ from normal. Thus, intensive sprinter training seems to dilate the left ventricle but causes less increase in wall thickness and mass than training for endurance running and no change in left ventricular function or left atrial size. Endurance running causes left ventricular dilatation equal to that of sprinter training, greater wall hypertrophy and improved systolic emptying of the left ventricle, and it also dilates the left atrium perhaps because of decreased left ventricular compliance.

  2. [The impact factor: a factor of impact or the impact of a (sole) factor? The limits of a bibliometric indicator as a candidate for an instrument to evaluate scientific production].

    Science.gov (United States)

    Gensini, G F; Conti, A A

    1999-01-01

    The Impact Factor is a bibliometric quantitative parameter introduced in 1971 and used to evaluate, classify and compare scientific journals. It is essentially the ratio between the number of citations they receive, computed on the basis of those included in the Science Citation Index, and the number of published articles. It is thus a dynamic parameter and an indicator of the editorial quality of a journal. It has also been considered a putative index of the scientific production of a single author. The Impact Factor was first proposed as a useful instrument for planning library choices, programming personal journal buying and reading, and directing scientific journal editors in their editorial strategies. However, since among the numerous variables which may influence the Impact Factor there are such parameters as: the average number of bibliographical references in a single article, self-citations, "salami publications", the Impact Factor, though adequate to judge entities such as journals, institutions and whole scientific communities, seems on the contrary inadequate to evaluate accurately the quality of the single investigator, paper, and research group. Furthermore, a limited number of papers, all focused on the so-called "hot topics", may contribute to increase the Impact Factor of a single journal. There is therefore still much research to be done to find truly "objective" methods to evaluate critically the "quality" (and not only the "quantity") of the work of a single author, a scientific group, and an entire institution, so that not only quantitative, but also qualitative evidence may be acquired!

  3. Recent population size, trends, and limiting factors for the double-crested Cormorant in Western North America

    Science.gov (United States)

    Adkins, Jessica Y.; Roby, Daniel D.; Lyons, Donald E.; Courtot, Karen N.; Collis, Ken; Carter, Harry R.; Shuford, W. David; Capitolo, Phillip J.

    2014-01-01

    colonies by bald eagles (Haliaeetus leucocephalus) and humans are likely limiting factors on the growth of the western population at present. Because of differences in biology and management, the western population of double-crested cormorants warrants consideration as a separate management unit from the population east of the Continental Divide.

  4. Mine Lifecycle Planning and Enduring Value for Remote communities

    Directory of Open Access Journals (Sweden)

    Stuart Robertson

    2014-09-01

    Full Text Available Mine lifecycle planning is critical to developing enduring value from mining for remote communities. The history of mining is replete with examples of communities being unsustainable post mine closure. The concept of enduring value involves ensuring that a sustainable community will remain following the closure of an associated mine. Since 2003, awareness has increased amongst the International and Australian peak mining bodies for the need to plan for enduring community value. This increased awareness has developed alongside the requirement for mining companies to operate in a socially responsible manner by maintaining a social license to operate. This paper thematically reviews the literature relevant to mine life cycle planning, enduring value, the socio-economic impacts of mining, and mine closure. Conditions required for a community to gain enduring value from mining include: ‘normalisation’ rather than being a ‘closed’ town; the existence of government support and funding; and realised economic diversification opportunities. It is imperative that these conditions are given due consideration 1 in the initial stages of mine and town planning and 2 throughout the life of the mine through ongoing monitoring and community engagement. However, we acknowledge the shortcomings in assuming planning is a panacea and suggest areas for further testing.

  5. Limitations in Activities of Daily Living in Community-Dwelling People Aged 75 and Over: A Systematic Literature Review of Risk and Protective Factors

    Science.gov (United States)

    Zijlstra, G. A. Rixt; Witte, Nico De; Duppen, Daan; Stuck, Andreas E.; Kempen, Gertrudis I. J. M.; Schols, Jos M. G. A.

    2016-01-01

    Background Most older people wish to age in place, for which functional status or being able to perform activities of daily living (ADLs) is an important precondition. However, along with the substantial growth of the (oldest) old, the number of people who develop limitations in ADLs or have functional decline dramatically increases in this part of the population. Therefore, it is important to gain insight into factors that can contribute to developing intervention strategies at older ages. As a first step, this systematic review was conducted to identify risk and protective factors as predictors for developing limitations in ADLs in community-dwelling people aged 75 and over. Methods Four electronic databases (CINAHL (EBSCO), EMBASE, PsycINFO and PubMed) were searched systematically for potentially relevant studies published between January 1998 and March 2016. Results After a careful selection process, 6,910 studies were identified and 25 were included. By far most factors were examined in one study only, and most were considered risk factors. Several factors do not seem to be able to predict the development of limitations in ADLs in people aged 75 years and over, and for some factors ambiguous associations were found. The following risk factors were found in at least two studies: higher age, female gender, diabetes, hypertension, and stroke. A high level of physical activity and being married were protective in multiple studies. Notwithstanding the fact that research in people aged 65 years and over is more extensive, risk and protective factors seem to differ between the ‘younger’ and ‘older’ olds. Conclusion Only a few risk and protective factors in community-dwelling people aged 75 years and over have been analysed in multiple studies. However, the identified factors could serve both detection and prevention purposes, and implications for future research are given as well. PMID:27760234

  6. Long-term low-calorie low-protein vegan diet and endurance exercise are associated with low cardiometabolic risk.

    Science.gov (United States)

    Fontana, Luigi; Meyer, Timothy E; Klein, Samuel; Holloszy, John O

    2007-06-01

    Western diets, which typically contain large amounts of energy-dense processed foods, together with a sedentary lifestyle are associated with increased cardiometabolic risk. We evaluated the long-term effects of consuming a low-calorie low-protein vegan diet or performing regular endurance exercise on cardiometabolic risk factors. In this cross-sectional study, cardiometabolic risk factors were evaluated in 21 sedentary subjects, who had been on a low-calorie low-protein raw vegan diet for 4.4 +/- 2.8 years, (mean age, 53.1 +/- 11 yrs), 21 body mass index (BMI)-matched endurance runners consuming Western diets, and 21 age- and gender-matched sedentary subjects, consuming Western diets. BMI was lower in the low-calorie low-protein vegan diet (21.3 +/- 3.1 kg/m(2)) and endurance runner (21.1 +/- 1.6 kg/m(2)) groups than in the sedentary Western diet group (26.5 +/- 2.7 kg/m(2)) (p vegan diet and runner groups than in the Western diet group (all p vegan diet group (104 +/- 15 and 62 +/- 11 mm Hg) than in BMI-matched endurance runners (122 +/- 13 and 72 +/- 9 mmHg) and Western diet group (132 +/- 14 and 79 +/- 8 mm Hg) (p vegan diet or regular endurance exercise training is associated with low cardiometabolic risk. Moreover, our data suggest that specific components of a low-calorie low-protein vegan diet provide additional beneficial effects on blood pressure.

  7. Pedalling rate affects endurance performance during high-intensity cycling

    DEFF Research Database (Denmark)

    Nielsen, Jens Steen; Hansen, Ernst Albin; Sjøgaard, Gisela

    2004-01-01

    , such as muscle fibre type composition and power reserve, relate to endurance time. Twenty males underwent testing to determine their maximal oxygen uptake (VO(2max)), power output corresponding to 90% of VO(2max) at 80 rpm (W90), FCPR at W90, percentage of slow twitch muscle fibres (% MHC I), maximal leg power...... time was negatively related to VO(2max), W90 and % MHC I, while positively related to power reserve. In conclusion, at group level, endurance time was longer at FCPR and at a pedalling rate 25% lower compared to a pedalling rate 25% higher than FCPR. Further, inter-individual physiological variables......The purpose of this study into high-intensity cycling was to: (1) test the hypothesis that endurance time is longest at a freely chosen pedalling rate (FCPR), compared to pedalling rates 25% lower (FCPR-25) and higher (FCPR+25) than FCPR, and (2) investigate how physiological variables...

  8. Thermoregulation and endurance running in extinct hominins: Wheeler's models revisited.

    Science.gov (United States)

    Ruxton, Graeme D; Wilkinson, David M

    2011-08-01

    Thermoregulation is often cited as a potentially important influence on the evolution of hominins, thanks to a highly influential series of papers in the Journal of Human Evolution in the 1980s and 1990s by Peter Wheeler. These papers developed quantitative modeling of heat balance between different potential hominins and their environment. Here, we return to these models, update them in line with new developments and measurements in animal thermal biology, and modify them to represent a running hominin rather than the stationary form considered previously. In particular, we use our modified Wheeler model to investigate thermoregulatory aspects of the evolution of endurance running ability. Our model suggests that for endurance running to be possible, a hominin would need locomotive efficiency, sweating rates, and areas of hairless skin similar to modern humans. We argue that these restrictions suggest that endurance running may have been possible (from a thermoregulatory viewpoint) for Homo erectus, but is unlikely for any earlier hominins.

  9. Carbohydrate mouth rinse: does it improve endurance exercise performance?

    Directory of Open Access Journals (Sweden)

    Painelli Vitor

    2010-08-01

    Full Text Available Abstract It is well known that carbohydrate (CHO supplementation can improve performance in endurance exercises through several mechanisms such as maintenance of glycemia and sparing endogenous glycogen as well as the possibility of a central nervous-system action. Some studies have emerged in recent years in order to test the hypothesis of ergogenic action via central nervous system. Recent studies have demonstrated that CHO mouth rinse can lead to improved performance of cyclists, and this may be associated with the activation of brain areas linked to motivation and reward. These findings have already been replicated in other endurance modalities, such as running. This alternative seems to be an attractive nutritional tool to improve endurance exercise performance.

  10. Effects of yoga practice on muscular endurance in young women.

    Science.gov (United States)

    Shiraishi, Juliana Costa; Bezerra, Lídia Mara Aguiar

    2016-02-01

    The aim of this study was to verify the effects of a systematized yoga practice on muscular endurance in young women. Twenty six women (24 ± 3.5 years old) participated in six weeks of yoga classes, and twenty one women (25 ± 5.1 years old) participated as the control group. The yoga intervention was composed of eighteen sessions, three times per week, at 1 h per session. The muscular endurance of upper limbs (push-up) and abdominal (sit-up) was assessed through the protocol suggested by Gettman (1989) [1] and Golding, Myers and Sinning (1989) [2] to the maximum repetitions performed in 1 min. To verify the significant differences intra groups and between groups a SPANOVA was performed, and the level of significance was p ≤ 0.05. The findings suggest that yoga provides improvement in upper limb and in abdominal muscular endurance.

  11. Endurance training: is it bad for you?

    Directory of Open Access Journals (Sweden)

    Giuseppe Morici

    2016-06-01

    Endurance exercise training exerts many positive effects on health, including improved metabol­ism, reduction of cardiovascular risk, and reduced all-cause and cardiovascular mortality. Intense endurance exercise causes mild epithelial injury and inflammation in the airways, but does not appear to exert detrimental effects on respiratory health or bronchial reactivity in recreational/non-elite athletes. Conversely, elite athletes of both summer and winter sports show increased susceptibility to development of asthma, possibly related to environmental exposures to allergens or poor conditioning of inspired air, so that a distinct phenotype of “sports asthma” has been proposed to characterise such athletes, who more often practise aquatic and winter sports. Overall, endurance training is good for health but may become deleterious when performed at high intensity or volume.

  12. Adaptations to speed endurance training in highly trained soccer players

    DEFF Research Database (Denmark)

    Nyberg, Michael Permin; Fiorenza, Matteo; Lund, Anders

    2016-01-01

    PURPOSE: The present study examined whether a period of additional speed endurance training would improve intense intermittent exercise performance in highly trained soccer players during the season and whether the training changed aerobic metabolism and the level of oxidative enzymes in type I...... and II muscle fibers. METHODS: During the last nine weeks of the season, thirteen semi-professional soccer players performed additional speed endurance training sessions consisting of 2-3 sets of 8 - 10 repetitions of 30 m sprints with 10 s of passive recovery (SET). Before and after SET, subjects...... in type I and II fibers did not change. CONCLUSION: In highly trained soccer players, additional speed endurance training is associated with an improved ability to perform repeated high-intensity work. To what extent the training-induced changes in V˙O2 kinetics and mechanical efficiency in type I fibers...

  13. Break point of serum creatine kinase release after endurance exercise.

    Science.gov (United States)

    Totsuka, Manabu; Nakaji, Shigeyuki; Suzuki, Katsuhiko; Sugawara, Kazuo; Sato, Koki

    2002-10-01

    We investigated whether there is a break point of creatine kinase (CK) release after daily endurance exercise and whether CK response depends on individual physical characteristics. Fifteen healthy young men performed 90 min of bicycle exercise for 3 consecutive days. Body composition, properties of the quadriceps femoris muscle (QFM), and aerobic and anaerobic capacities were estimated before the test. Blood samples were obtained 22 times during the experimental period. Endurance exercise significantly elevated serum CK from 3 h after the first exercise session (P 500 IU/l of CK) and low responders (LR; break point of CK release after endurance exercise under these conditions is 300-500 IU/l, two or three times higher than in the resting condition, and is associated with properties of the QFM.

  14. Prevalence of exertional rhabdomyolysis in endurance horses in the Pacific Northwestern United States.

    Science.gov (United States)

    Wilberger, M S; McKenzie, E C; Payton, M E; Rigas, J D; Valberg, S J

    2015-03-01

    Exertional rhabdomyolysis (ER) is a reported syndrome in competing endurance horses; however, the prevalence and cause of ER in this population have not been defined. To determine the prevalence of ER in a sample of endurance racing horses and investigate factors, including relevant genetic defects, contributing to the occurrence of rhabdomyolysis in this group. Prospective clinical study. Riders of 101 horses participating in one of four 50-mile (80.5 km) distance races completed a comprehensive questionnaire regarding the medical history, management and performance of their horse. Serum creatine kinase activity (CK) was measured before and 4 h after completion of exercise. Hair samples were analysed by PCR for the R309H mutation in the glycogen synthase gene (GYS1) responsible for type 1 polysaccharide storage myopathy (PSSM) and the C7360G mutation in the ryanodine receptor 1 (RYR1) gene causing malignant hyperthermia (MH). Samples were obtained from 68 Arabians, 20 half-Arabians and 13 horses of other breeds. Serum CK was above the resting reference interval (145-633 u/l) in 38 horses after racing (median 883 u/l, range 658-3739) but was compatible with values previously reported in apparently healthy endurance horses. Pathological ER was suspected to occur in 4 horses with serum CK activities exceeding 10,000 u/l 4 h after racing (median 84,825 u/l; range 10,846-381,790) including 3 Arabians and one half-Arabian horse. GYS1 and RYR1 mutations were not present in hair samples from any horses. Exertional rhabdomyolysis occurred at a prevalence of 4.0% in a sample of horses participating in 50 mile distance events and all affected horses were Arabian or half-Arabian. The cause of ER in the endurance horse population remains unknown; however, ER in competing Arabian endurance horses is unlikely to be due to type 1 PSSM or MH. © 2014 EVJ Ltd.

  15. Effects of Age, Exercise Duration, and Test Conditions on Heart Rate Variability in Young Endurance Horses.

    Science.gov (United States)

    Younes, Mohamed; Robert, Céline; Barrey, Eric; Cottin, François

    2016-01-01

    Although cardiac recovery is an important criterion for ranking horses in endurance competitions, heart rate variability (HRV) has hardly ever been studied in the context of this equestrian discipline. In the present study, we sought to determine whether HRV is affected by parameters such as age, exercise duration and test site. Accordingly, HRV might be used to select endurance horses with the fastest cardiac recovery. The main objective of the present study was to determine the effects of age, exercise duration, and test site on HRV variables at rest and during exercise and recovery in young Arabian endurance horses. Over a 3-year period, 77 young Arabian horses aged 4-6 years performed one or more exercise tests (consisting of a warm-up, cantering at 22 km.h(-1)and a final 500 m gallop at full speed) at four different sites. Beat-to-beat RR intervals were continuously recorded and then analyzed (using a time-frequency approach) to determine the instantaneous HRV components before, during and after the test. At rest, the root-mean-square of successive differences in RR intervals (RMSSD) was higher in the 4-year-olds (54.4 ± 14.5 ms) than in the 5-or 6-year-olds (44.9 ± 15.5 and 49.1 ± 11.7 ms, respectively). During the first 15 min of exercise (period T), the heart rate (HR) and RMSSD decreased with age. In 6-year-olds, RMSSD decreased as the exercise duration increased (T: 3.0 ± 1.4 vs. 2T: 3.6 ± 2.2 vs. 3T: 2.8 ± 1.0). During recovery, RMSSD was negatively correlated with the cardiac recovery time (CRT) and the recovery heart rate (RHR; R = -0.56 and -0.53, respectively; p exercise and recovery, RMSSD and several HRV variables differed significantly as a function of the test conditions. HRV in endurance horses appears to be strongly influenced by age and environmental factors (such as ambient temperature, ambient humidity, and track quality). Nevertheless, RMSSD can be used to select endurance horses with the fastest cardiac recovery.

  16. Conjugated linoleic acid (CLA) promotes endurance capacity via peroxisome proliferator-activated receptor δ-mediated mechanism in mice.

    Science.gov (United States)

    Kim, Yoo; Kim, Daeyoung; Park, Yeonhwa

    2016-12-01

    Previously, it was reported that conjugated linoleic acid (CLA) with exercise training potentially improved endurance capacity via the peroxisome proliferator-activated receptor δ (PPARδ)-mediated mechanism in mice. This study determined the role of exercise and/or CLA in endurance capacity and PPARδ-associated regulators. Male 129Sv/J mice were fed either control (soybean oil) or CLA (0.5%) containing diets for 4 weeks and were further divided into sedentary or training regimes. CLA supplementation significantly reduced body weight and fat mass independent of exercise during the experimental period. Endurance capacity was significantly improved by CLA supplementation, while no effect of exercise was observed. Similarly, CLA treatment significantly increased expressions of sirtuin 1 and PPARγ coactivator-1α, up-stream regulators of PPARδ, in both sedentary and trained animals. With respect to downstream markers of PPARδ, CLA up-regulated the key biomarker needed to stimulate mitochondrial biogenesis, nuclear respiratory factor 1. Moreover, CLA supplementation significantly induced overall genes associated with muscle fibers, such as type I (slow-twitch) and type II (fast twitch). Taken together, it suggests that CLA improves endurance capacity independent of mild-intensity exercise via PPARδ-mediated mechanism.

  17. Obesity as a risk factor for developing functional limitation among older adults: A conditional inference tree analysis

    Science.gov (United States)

    Objective: To examine the risk factors of developing functional decline and make probabilistic predictions by using a tree-based method that allows higher order polynomials and interactions of the risk factors. Methods: The conditional inference tree analysis, a data mining approach, was used to con...

  18. Relationships between body dimensions, body weight, age, gender, breed and echocardiographic dimensions in young endurance horses

    DEFF Research Database (Denmark)

    Trachsel, D S; Giraudet, A; Maso, D

    2016-01-01

    BACKGROUND: The heart's physiological adaptation to aerobic training leads to an increase in heart chamber size, and is referred to as the Athlete's heart. However, heart dimensions are also related to body weight (BWT), body size, growth and (in some species) breed. There are few published data...... functional indices did not. Although there was no gender difference for LV dimensions, females had larger LA dimensions. In terms of breed, Anglo-Arabians had the largest LV dimensions. Regression models indicated that the included explanatory factors had a weak influence on heart dimensions. Age, body...... may therefore reflect early adaptations linked to the initiation of endurance training....

  19. RELATIONSHIPS BETWEEN MUSCLE FATIGUE CHARACTERISTICS AND MARKERS OF ENDURANCE PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Martyn G. Morris

    2008-12-01

    Full Text Available The aim of this study was to examine the relationship of a range of in-vivo whole muscle characteristics to determinants of endurance performance. Eleven healthy males completed a cycle ergometer step test to exhaustion for the determination of the lactate threshold, gross mechanical efficiency, peak power and VO2max. On two separate occasions, contractile and fatigue characteristics of the quadriceps femoris were collected using a specially designed isometric strength-testing chair. Muscle fatigue was then assessed by stimulating the muscle for 3 minutes. Force, rate of force development and rates of relaxation were calculated at the beginning and end of the 3 minute protocol and examined for reliability and in relation to lactate threshold, VO2max, gross mechanical efficiency and peak power. Muscle characteristics, rate of force development and relaxation rate were demonstrated to be reliable measures. Force drop off over the 3 minutes (fatigue index was related to lactate threshold (r = -0.72 p < 0.01 but not to VO2max. The rate of force development related to the peak power at the end of the cycle ergometer test (r = -0.75 p < 0.01. Rates of relaxation did not relate to any of the performance markers. We found in-vivo whole muscle characteristics, such as the fatigue index and rate of force development, relate to specific markers of peripheral, but not to central, fitness components. Our investigation suggests that muscle characteristics assessed in this way is reliable and could be feasibly utilised to further our understanding of the peripheral factors underpinning performance

  20. A power recirculating test rig for ball screw endurance tests

    Directory of Open Access Journals (Sweden)

    Giberti Hermes

    2016-01-01

    Full Text Available A conceptual design of an innovative test rig for endurance tests of ball screws is presented in this paper. The test rig layout is based on the power recirculating principle and it also allows to overtake the main critical issues of the ball screw endurance tests. Among these there are the high power required to make the test, the lengthy duration of the same and the high loads between the screw and the frame that holds it. The article describes the test rig designed scheme, the kinematic expedients to be adopted in order to obtain the required performance and functionality and the sizing procedure to choose the actuation system.

  1. Cardiac adaptation to acute and chronic participation in endurance sports.

    Science.gov (United States)

    George, Keith; Spence, Angela; Naylor, Louise H; Whyte, Gregory P; Green, Daniel J

    2011-12-01

    The pervasive public health message is that moderate amounts of endurance exercise help maintain optimal health and reduce cardiovascular risk. While not enough people meet national physical activity guidelines, there are some at the opposite end of the activity spectrum who far exceed the recommended 'dose' of exercise. The cardiovascular health consequences of single and/or multiple (lifelong) 'doses' of high-volume endurance exercise are currently being debated. Recent commentaries, case reports and case series data have posed the question whether you can 'overdose on exercise', and that is the focus of this brief review.

  2. SPORTS ANAEMIA IN ENDURANCE ATHLETES: A PHYSIOLOGICAL PHENOMENON

    Directory of Open Access Journals (Sweden)

    Anil B Warkar

    2015-07-01

    Full Text Available Endurance athletes require a very efficient oxygen transport system for maximal aerobic power during physical work performance. Many studies carried on endurance athletes suggested low levels of red blood cell markers leading to misconception of existence of so called sports anaemia in athletes. Sometimes athletes are on needless iron supplementation and are concern about anaemia. The main objectives of the study were to investigate the red cell population markers and to study the sports anaemia phenomenon in endurance athletes and the underlying responses responsible for ot. 60 male endurance track and field runners age group 18-21 were selected from the local city based club named Vasant Desai Krida Sangh Akola and were compared with the age, height sex matched non athletes students of Govt. Medical College Akola. The seven red blood cell markers were studied from the blood samples taken from the cubital vein under standard conditions. The blood variables for both the groups were analyzed with an automatic cell counter. The mean values of Hb(12.27 gm% +/- 0.782, RBC count in(3.64millions per cu mm+/-0.52, hematocrit ( 41.58 % +/- 1.32, mean corpuscular Hb conc (MCHC 29.49% +/- 1.198 were all very significantly lower ( p<0.0001 as compare to controls. Whereas the plasma volume (58.412% +/- 1.32, Mean Corpuscular volume (MCV 115.06 cu microns+/- 11.54, Mean Hb conc (MCH 33.998 picogms+/- 2.608, were significantly increased in endurance athletes. Though decrease in Hb conc, Low RBC count and less hematocrit in endurance athletes indicate presence of anaemia in them but it’s not a true anaemia as it is also confirmed by MCV, MCH, MCHC values between the two groups. The significant differences between the groups are due to the response to endurance training leading to hemo dilutional anaemia caused by plasma volume expansion which increases the blood volume in endurance athletes helping them for better oxygen supply and aerobic power needed

  3. The abiotic and biotic factors limiting establishment of predatory fishes at their expanding northern range boundaries in Ontario, Canada.

    Science.gov (United States)

    Alofs, Karen M; Jackson, Donald A

    2015-06-01

    There is a poor understanding of the importance of biotic interactions in determining species distributions with climate change. Theory from invasion biology suggests that the success of species introductions outside of their historical ranges may be either positively (biotic acceptance) or negatively (biotic resistance) related to native biodiversity. Using data on fish community composition from two survey periods separated by approximately 28 years during which climate was warming, we examined the factors influencing the establishment of three predatory centrarchids: Smallmouth Bass (Micropterus dolomieu), Largemouth Bass (M. salmoides), and Rock Bass (Ambloplites rupestris) in lakes at their expanding northern range boundaries in Ontario. Variance partitioning demonstrated that, at a regional scale, abiotic factors play a stronger role in determining the establishment of these species than biotic factors. Pairing lakes within watersheds where each species had established with lakes sharing similar abiotic conditions where the species had not established revealed both positive and negative relationships between the establishment of centrarchids and the historical presence of other predatory species. The establishment of these species near their northern range boundaries is primarily determined by abiotic factors at a regional scale; however, biotic factors become important at the lake-to-lake scale. Studies of exotic species invasions have previously highlighted how spatial scale mediates the importance of abiotic vs. biotic factors on species establishment. Our study demonstrates how concepts from invasion biology can inform our understanding of the factors controlling species distributions with changing climate.

  4. Low skeletal muscle mass is a predictive factor for chemotherapy dose-limiting toxicity in patients with locally advanced head and neck cancer

    NARCIS (Netherlands)

    Wendrich, Anne W; Swartz, Justin E; Bril, Sandra I; Wegner, Inge; de Graeff, Alexander|info:eu-repo/dai/nl/187695997; Smid, Ernst J; de Bree, Remco; Pothen, Ajit J

    OBJECTIVES: Low skeletal muscle mass (SMM) or sarcopenia is emerging as an adverse prognostic factor for chemotherapy dose-limiting toxicity (CLDT) and survival in cancer patients. Our aim was to determine the impact of low SMM on CDLT in patients with locally advanced head and neck squamous cell

  5. Effect of speed endurance and strength training on performance, running economy and muscular adaptations in endurance-trained runners

    DEFF Research Database (Denmark)

    Vorup Petersen, Jacob; Tybirk Nielsen, Jonas; Gunnarsson, Thomas Petursson;

    2016-01-01

    period. Maximal aerobic speed was 0.6 km h(-1) higher (P ...PURPOSE: To investigate the effects of combined strength and speed endurance (SE) training along with a reduced training volume on performance, running economy and muscular adaptations in endurance-trained runners. METHODS: Sixteen male endurance runners (VO2-max: ~60 ml kg(-1) min(-1)) were...... randomly assigned to either a combined strength and SE training (CSS; n = 9) or a control (CON; n = 7) group. For 8 weeks, CSS replaced their normal moderate-intensity training (~63 km week(-1)) with SE (2 × week(-1)) and strength training (2 × week(-1)) as well as aerobic high (1 × week(-1)) and moderate...

  6. Limited socioeconomic opportunities and Latina teen childbearing: a qualitative study of family and structural factors affecting future expectations.

    Science.gov (United States)

    Minnis, Alexandra M; Marchi, Kristen; Ralph, Lauren; Biggs, M Antonia; Combellick, Sarah; Arons, Abigail; Brindis, Claire D; Braveman, Paula

    2013-04-01

    The decrease in adolescent birth rates in the United States has been slower among Latinas than among other ethnic/racial groups. Limited research has explored how socioeconomic opportunities influence childbearing among Latina adolescents. We conducted in-depth interviews with 65 pregnant foreign- and US-born Latina women (31 adolescents; 34 adults) in two California counties. We assessed perceived socioeconomic opportunities and examined how family, immigration and acculturation affected the relationships between socioeconomic opportunities and adolescent childbearing. Compared with women who delayed childbearing into adulthood, pregnant adolescents described having few resources for educational and career development and experiencing numerous socioeconomic and social barriers to achieving their goals. Socioeconomic instability and policies limiting access to education influenced childbearing for immigrant adolescents. In contrast, family disintegration tied to poverty figured prominently in US-born adolescents' childbearing. Limited socioeconomic opportunities may play a large role in persistently high pregnancy rates among Latina adolescents.

  7. LATIHAN ENDURANCE MENINGKATKAN KUALITAS HIDUP LEBIH BAIK DARI PADA LATIHAN PERNAFASAN PADA PASIEN PPOK DI BP4 YOGYAKARTA

    Directory of Open Access Journals (Sweden)

    Siti Khotimah

    2013-07-01

    Full Text Available Quality of life is an individual state within the scope of capabilities, limitations, symptoms, and psychosocial natures to function in the desired range of roles in society and feel satisfied with that role. Quality of life of COPD patient’s considered very important because it relates directly to the symptoms experienced. In COPD patients increased work causes shortness of breath so that the patients had decreased quality of life. There  has been indication that endurance exercise and breathing exercise improve quality of life in COPD patient. This study was aimed at testing endurance exercise in improving the quality of life of COPD patients. The study is a quasi experiment with pre-test and post-test control group design. The experiment was conducted in BP4 Yogyakarta. The number of samples was 22 patients with COPD who experienced of reducing quality of life. Quality of life in COPD patients measured by SGRQ questionnaires. The number of study subjects were then grouped at random into two groups. Control group one was given diaphragmatic breathing exercise and pursed lip breathing three times a week. Treatment group two was given endurance exercise three times a week. The study was conducted for 12 weeks. SGRQ total value of the data was measured before and after treatment. All data in the analysis using SPSS version 16. Data are destributed normal and homogen, a decrease in the total SGRQ meaningful on breathing exercises and endurance training with a value of p = 0.000 (p <0.05. This means that breathing exercises and endurance exercises at same time can significantly improve the quality of life. The mean total SGRQ values ??after treatment in group one and group two significantly different, where the value of p <0.05, namely p = 0.000, a decrease of group two’s SGRQ total value greater than group one. This means that endurance exercise improves quality of life better than breathing exercises in COPD patients in BP4 Yogyakarta. It is

  8. Increasing the electrical discharge endurance of acid anhydride cured DGEBA epoxy resin by dispersion of nanoparticle silica. High Perform. Polym. 11 (1999) pp 281-296 by IOP Publishing Ltd

    DEFF Research Database (Denmark)

    Henk, Peter O; Kortsen, T.W.; Kvarts, T.

    1999-01-01

    combinations were used: (a) fumed nanoparticle silicon dioxide referred to as Aerosil, (b) equal volumes of Aerosil and nanoparticle anatase, and (c) Aerosil plus anatase in combination with coarse-particle filler grade calcium-magnesium carbonate dolomite. A test for endurance using the CIGRE method II...... the endurance by a factor of up to 20 as the Aerosil content goes from zero to 5.4 vol%. Aerosil mixed with anatase has a similar effect. The high level of endurance is maintained with an additional high-volume (35 vol.%) filling of coarse-particle dolomite to an epoxy system already containing Aerosil...

  9. A critical appraisal of experimental factors influencing the definition of the 99th percentile limit for cardiac troponins.

    Science.gov (United States)

    Panteghini, Mauro

    2009-01-01

    The recently released document by the Global Task Force on the "universal" definition of myocardial infarction (MI) recommends a single decision limit for cardiac troponin (cTn) corresponding to the 99th percentile limit of the reference value distribution [99th upper reference limit (URL)] for the diagnosis of patients presenting with suspected MI. However, use of this cut-off concentration posed a problem because most assays do not have the sensitivity to consistently measure cTn in the blood of apparently healthy individuals, with a high proportion of the values being below the method's detection limit. In addition to the influence of assay sensitivity, the 99th URL for cTn can vary depending on the reference population used, and its sample size. A marked difference can also be observed between the 99th URL obtained using plasma vs. that obtained with serum. Finally, some interferences with cTn measurement (e.g., by heterophile antibodies) may become more noticeable using assays that have increased analytical sensitivity that measure lower concentrations of these markers. In conclusion, a number of issues can markedly influence the definition of the 99th URL for cTn, which most clinicians are unaware of and may markedly condition the clinical performance of the test in routine practice.

  10. 4 Types of Exercise, Endurance | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... example, many endurance activities also build strength. Strength exercises also help improve balance. Endurance, or aerobic, activities increase your breathing and heart rate. They keep your heart, lungs, and circulatory system ...

  11. 舰船自给力设计要素分析%Analysis of Endurance Design Elements for Warships

    Institute of Scientific and Technical Information of China (English)

    吴凤辉; 张玉梅

    2015-01-01

    为全面分析舰船自给力设计要素,以标准规范中的定义为基础,结合舰船设计及使用情况,分析舰船自给力的概念;从食品和淡水两方面阐述自给力的影响因素、设计方法及主要设计参数选取;对舰船自给力研究的未来方向进行展望,提出需重点针对食品高效贮存、食品长时保鲜、海水淡化深度处理等技术进行研究,以在舰船总体资源有限的情况下,为舰员提供新鲜的食品、健康的饮水,提高舰船自给力水平。%In order to fully analyze endurance design elements for the warships, combined with instances of warships design and use, the conception of warships endurance is analyzed.From aspects of food and fresh water, influential factors, design method and design parameters choice of endurance are explained.The research development of endurance in future is prospected. In order to provide fresh food and healthy water to the persons in warships, and to improve the level of endurance of warships, it's important to researched on the technologies of high availability food reserve, keeping food long time fresh and deep disposal of sea water.

  12. Peculiarities of endurance development for first year students

    Directory of Open Access Journals (Sweden)

    Pochernina A.G.

    2014-04-01

    Full Text Available Purpose: to determine the dynamics of the specific endurance first-year students in the classroom of physical education. Material : the study involved 20 students. Conducted educational testing: seed of lifting in supine position, hang on bent arms, jumping from sitting up with the stop, run 30m, bending and straightening the arms in emphasis lying, tilt forward from a sitting position, shuttle run, broad jump start. Results : found that the passage of the training module volleyball observed development of specific endurance and all motor abilities. Established that the manifestation and development of motor skills are interrelated. Since force is a functional foundation for the development of other skills, flexibility - the foundation of all mechanical movements. Without the development of strength, speed, coordination abilities impossible to develop endurance. Therefore, it is inappropriate and incorrect receipt of unidirectional only specific endurance (dynamic power and static, speed-power. Conclusions: indicated the need to achieve functional specialization of the body in the direction which is necessary for high-level manifestation of certain motor skills.

  13. Biochemical aspects of overtraining in endurance sports: a review.

    Science.gov (United States)

    Petibois, Cyril; Cazorla, Georges; Poortmans, Jacques-Rémi; Déléris, Gérard

    2002-01-01

    Top-level performances in endurance sports require several years of hard training loads. A major objective of this endurance training is to reach the most elevated metabolic adaptations the athlete will be able to support. As a consequence, overtraining is a recurrent problem that highly-trained athletes may experience during their career. Many studies have revealed that overtraining could be highlighted by various biochemical markers but a principal discrepancy in the diagnosis of overtraining stems from the fact that none of these markers may be considered as universal. In endurance sports, the metabolic aspects of training fatigue appear to be the most relevant parameters that may characterise overtraining when recovery is not sufficient, or when dietary habits do not allow an optimal replenishment of substrate stores. From the skeletal muscle functions to the overall energetic substrate availability during exercise, six metabolic schemes have been studied in relation to overtraining, each one related to a central parameter, i.e. carbohydrates, branched-chain amino acids, glutamine, polyunsaturated fatty acids, leptin, and proteins. We summarise the current knowledge on these metabolic hypotheses regarding the occurrence of overtraining in endurance sports.

  14. Effect of ambient temperature on female endurance performance.

    Science.gov (United States)

    Renberg, Julie; Sandsund, Mariann; Wiggen, Øystein Nordrum; Reinertsen, Randi Eidsmo

    2014-10-01

    Ambient temperature can affect physical performance, and an ambient temperature range of -4 °C to 11 °C is optimal for endurance performance in male athletes. The few similar studies of female athletes appear to have found differences in response to cold between the genders. This study investigated whether ambient temperature affects female endurance performance. Nine athletes performed six tests while running on a treadmill in a climatic chamber at different ambient temperatures: 20, 10, 1, -4, -9 and -14 °C and a wind speed of 5 m s(-1). The exercise protocol consisted of a 10-min warm-up, followed by four 5-min intervals at increasing intensities at 76%, 81%, 85%, and 89% of maximal oxygen consumption. This was followed by an incremental test to exhaustion. Although peak heart rate, body mass loss, and blood lactate concentration after the incremental test to exhaustion increased as the ambient temperature rose, no changes in time to exhaustion, running economy, running speed at lactate threshold or maximal oxygen consumption were found between the different ambient temperature conditions. Endurance performance during one hour of incremental exercise was not affected by ambient temperature in female endurance athletes.

  15. Cardiopulmonary Fitness and Endurance in Children with Developmental Coordination Disorder

    Science.gov (United States)

    Wu, Sheng K.; Lin, Hsiao-Hui; Li, Yao-Chuen; Tsai, Chia-Liang; Cairney, John

    2010-01-01

    The purpose of this study was to compare cardiopulmonary fitness and endurance in 9-11-year-old children with DCD against a group of typically developing children in Taiwan. The Movement ABC test was used to evaluate the motor abilities of children. Forty-one participants (20 children with DCD and 21 children without DCD) were recruited for this…

  16. Endurance and age : evidence from long-distance running data

    NARCIS (Netherlands)

    Sterken, Elmer

    2001-01-01

    This paper analyzes the impact of aging on long-run endurance. We analyze the determinants of running speed on distances from 5K to the marathon. We model running speed as a function of distance, age, and sex. We find evidence for interaction between age and sex, but not between distance and sex.

  17. Endurance test of TiO2-based photocatalytic oxidation

    NARCIS (Netherlands)

    Assink, J.W.; Slaager, J.M.

    1998-01-01

    The long term behaviour of suspended photocatalysts (Degussa P25) is studied in two endurance tests. Model waste water with an acid dye (Special Brilliant Blue FFR) or 4-chlorophenol as main contaminant have been used. Titanium dioxide is recovered from the effluent by pressure filtration and reused

  18. Molecular responses to moderate endurance exercise in skeletal muscle

    Science.gov (United States)

    This study examined alterations in skeletal-muscle growth and atrophy-related molecular events after a single bout of moderate-intensity endurance exercise. Muscle biopsies were obtained from 10 men (23 +/- 1 yr, body mass 80 +/- 2 kg, and VO(2peak) 45 +/- 1 ml x kg'¹ x min'¹) immediately (0 hr) and...

  19. Ischemic Preconditioning Enhances Muscle Endurance during Sustained Isometric Exercise.

    Science.gov (United States)

    Tanaka, D; Suga, T; Tanaka, T; Kido, K; Honjo, T; Fujita, S; Hamaoka, T; Isaka, T

    2016-07-01

    Ischemic preconditioning (IPC) enhances whole-body exercise endurance. However, it is poorly understood whether the beneficial effects originate from systemic (e. g., cardiovascular system) or peripheral (e. g., skeletal muscle) adaptations. The present study examined the effects of IPC on local muscle endurance during fatiguing isometric exercise. 12 male subjects performed sustained isometric unilateral knee-extension exercise at 20% of maximal voluntary contraction until failure. Prior to the exercise, subjects completed IPC or control (CON) treatments. During exercise trial, electromyography activity and near-infrared spectroscopy-derived deoxygenation in skeletal muscle were continuously recorded. Endurance time to task failure was significantly longer in IPC than in CON (mean±SE; 233±9 vs. 198±9 s, PIPC and CON. In contrast, deoxygenation dynamics in the quadriceps vastus lateralis muscle was significantly faster in IPC than in CON (27.1±3.4 vs. 35.0±3.6 s, PIPC can enhance muscular endurance during fatiguing isometric exercise. Moreover, IPC accelerated muscle deoxygenation dynamics during the exercise. Therefore, we suggest that the origin of beneficial effects of IPC on exercise performance may be the enhanced mitochondrial metabolism in skeletal muscle.

  20. Recommendations for healthy nutrition in female endurance runners: an update

    Directory of Open Access Journals (Sweden)

    Louise eDeldicque

    2015-05-01

    Full Text Available The purpose of this review is to present the basic principles of a healthy nutrition in female endurance runner enriched by the latest scientific recommendations. Female endurance runners are a specific population of athletes who need to take specifically care of daily nutrition due to the high load of training and the necessity to keep a rather low body mass. This paradoxical situation can create some nutritional imbalances and deficiencies. Female endurance athletes should pay attention to their total energy intake, which is often lower than their energy requirement. The minimal energy requirement has been set to 45kcal/kg fat free mass/day plus the amount of energy needed for physical activity. The usual recommended amount of 1.2-1.4g protein/kg/day has recently been questioned by new findings suggesting that 1.6g/kg/day would be more appropriate for female athletes. Although a bit less sensitive to carbohydrate loading than their male counterparts, female athletes can benefit from this nutritional strategy before a race if the amount of carbohydrates reaches 8g/kg/day and if their daily total energy intake is sufficient. A poor iron status is a common issue in female endurance runners but iron-enriched food as well as iron supplementation may help to counterbalance this poor status. Finally, they should also be aware that they may be at risk for low calcium and vitamin D levels.

  1. Solution-Space Screening of a Hypersonic Endurance Demonstrator

    Science.gov (United States)

    Chudoba, Bernd; Coleman, Gary; Oza, Amit; Gonzalez, Lex; Czysz, Paul

    2012-01-01

    This report documents a parametric sizing study performed to develop a program strategy for research and development and procurement of a feasible next-generation hypersonic air-breathing endurance demonstrator. Overall project focus has been on complementing technical and managerial decision-making during the earliest conceptual design phase towards minimization of operational, technical, and managerial risks.

  2. Instructions to Adopt an External Focus Enhance Muscular Endurance

    Science.gov (United States)

    Marchant, David C.; Greig, Matt; Bullough, Jonathan; Hitchen, Daniel

    2011-01-01

    The influence of internal (movement focus) and external (outcome focus) attentional-focusing instructions on muscular endurance were investigated using three exercise protocols with experienced exercisers. Twenty-three participants completed a maximal repetition, assisted bench-press test on a Smith's machine. An external focus of attention…

  3. The Effect of Variant Dosages of Amphetamine Upon Endurance.

    Science.gov (United States)

    Williams, Melvin H.; Thompson, John

    The purpose of this study was to provide basic information concerning the acute effects of a small, moderate, and large dose of d-amphetamine sulfate upon muscular endurance; a secondary purpose involved the effect upon resting (R), and submaximal, and maximal (MAX) heart rate (HR). Twelve male university students underwent four separate trials of…

  4. Soil types and limiting factors in agricultural production in the San Fernando district, Tamaulipas, Mexico; Tipos de suelo y factores limitantes en la produccion agropecuaria en el distrito San Fernando, Tamaulipas, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Espinosa Ramirez, M.; Garza Cedillo, R.; Andrade limas, E.; Belmonte Serrato, F.

    2009-07-01

    The limiting factors in agricultural production, defined as those properties and characteristics of the geographical environment that influence the development of crops, can be diverse and are grouped with the physical environment of soil. They are the result of soil characteristics and soil degradation processes by anthropogenic influence. Due to the above, the objective of this study was to identify and surveying the limitative factors to agricultural production, as well as to define its ability land use capacity in San Fernando district, Tamaulipas. (Author) 7 refs.

  5. Limited clinical efficacy of azacitidine in transfusion-dependent, growth factor-resistant, low- and Int-1-risk MDS

    DEFF Research Database (Denmark)

    Dybedahl, I; Holm, Mette; Karimi, M

    2014-01-01

    This prospective phase II study evaluated the efficacy of azacitidine (Aza)+erythropoietin (Epo) in transfusion-dependent patients with lower-risk myelodysplastic syndrome (MDS). Patients ineligible for or refractory to full-dose Epo+granulocyte colony stimulation factors for >8 weeks and a trans...

  6. No Effect of Exercise Intensity on Appetite in Highly-Trained Endurance Women.

    Science.gov (United States)

    Howe, Stephanie M; Hand, Taryn M; Larson-Meyer, D Enette; Austin, Kathleen J; Alexander, Brenda M; Manore, Melinda M

    2016-04-18

    In endurance-trained men, an acute bout of exercise is shown to suppress post-exercise appetite, yet limited research has examined this response in women. The purpose of this study was to investigate the effect of exercise intensity on appetite and gut hormone responses in endurance-trained women. Highly-trained women (n = 15, 18-40 years, 58.4 ± 6.4 kg, VO2MAX = 55.2 ± 4.3 mL/kg/min) completed isocaloric bouts (500 kcals or 2093 kJ) of moderate-intensity (MIE, 60% VO2MAX) and high-intensity (HIE, 85% VO2MAX) treadmill running at the same time of day, following a similar 48-h diet/exercise period, and at least 1-week apart. Blood was drawn pre-exercise (baseline), immediately post-exercise and every 20-min for the next 60-min. Plasma concentrations of acylated ghrelin, PYY3-36, GLP-1 and subjective appetite ratings via visual analog scale (VAS) were assessed at each time point. Acylated ghrelin decreased (p = 0.014) and PYY3-36 and GLP-1 increased (p = 0.036, p appetite suppression. VAS ratings of hunger and desire to eat decreased immediately post-exercise (p = 0.0012, p = 0.0031, respectively), also indicating appetite suppression. There were no differences between exercise intensities for appetite hormones or VAS. Similar to males, post-exercise appetite regulatory hormones were altered toward suppression in highly-trained women and independent of energy cost of exercise. Results are important for female athletes striving to optimize nutrition for endurance performance.

  7. Stress related changes during a half marathon in master endurance athletes.

    Science.gov (United States)

    Piacentini, M F; Minganti, C; Ferragina, A; Ammendolia, A; Capranica, L; Cibelli, G

    2015-04-01

    The aim of the present study was to investigate heart rate (HR), salivary cortisol (sC) alpha-amylase (sAA) and rating of perceived exertion (RPE) in relation to competition outcome during a half marathon. HR was monitored and salivary samples were collected during an official half marathon in five Master endurance runners (age 47 ± 7 years). RPE was collected using a 100-mm Visual Analogue Scale (VAS) 30 minutes after the end of competition. Performance corresponded to 94% of their personal best (PB). Athletes spent 53.7% of total race time at intensities above 95% HRmax. RPE showed values of 68 ± 8 mm. With respect to pre-competition values (25.54 ± 6.39 nmol/L), sC concentrations significantly increased (P=0.043) by 59% immediately after the race (40.54 ± 3.95 nmol/L) and remained elevated until 1 h post exercise. Pre-competition sAA concentrations (90.59 ± 42.86 U/mL) were 118% higher (P=0.043) with respect to time-matched baseline values (197.92 ± 132 U/mL). sAA increased (192%; P=0.043) immediately after the race and was higher than time-matched resting samples. The better each athlete performed the greater cortisol increase during exercise (Pcorrelated to the anticipatory sAA (the percent difference between pre-competition values and time-matched baseline ones) or to the sAA increase during exercise. This is the first attempt to study the stress-related responses during official endurance competitions in master runners. Although the strict criteria of inclusion might have limited the statistical significance, the present findings indicate that endurance competition is a remarkable stressor for psycho-physiological aspects of master athletes.

  8. Does Carbohydrate Intake During Endurance Running Improve Performance? A Critical Review.

    Science.gov (United States)

    Wilson, Patrick B

    2016-12-01

    Wilson, PB. Does carbohydrate intake during endurance running improve performance? A critical review. J Strength Cond Res 30(12): 3539-3559, 2016-Previous review articles assessing the effects of carbohydrate ingestion during prolonged exercise have not focused on running. Given the popularity of distance running and the widespread use of carbohydrate supplements, this article reviewed the evidence for carbohydrate ingestion during endurance running. The criteria for inclusion were (a) experimental studies reported in English language including a performance task, (b) moderate-to-high intensity exercise >60 minutes (intermittent excluded), and (c) carbohydrate ingestion (mouth rinsing excluded). Thirty studies were identified with 76 women and 505 men. Thirteen of the 17 studies comparing a carbohydrate beverage(s) with water or a placebo found a between-condition performance benefit with carbohydrate, although heterogeneity in protocols precludes clear generalizations about the expected effect sizes. Additional evidence suggests that (a) performance benefits are most likely to occur during events >2 hours, although several studies showed benefits for tasks lasting 90-120 minutes; (b) consuming carbohydrate beverages above ad libitum levels increases gastrointestinal discomfort without improving performance; (c) carbohydrate gels do not influence performance for events lasting 16-21 km; and (d) multiple saccharides may benefit events >2 hours if intake is ≥1.3 g·min Given that most participants were fasted young men, inferences regarding women, adolescents, older runners, and those competing in fed conditions are hampered. Future studies should address these limitations to further elucidate the role of carbohydrate ingestion during endurance running.

  9. No Effect of Exercise Intensity on Appetite in Highly-Trained Endurance Women

    Directory of Open Access Journals (Sweden)

    Stephanie M. Howe

    2016-04-01

    Full Text Available In endurance-trained men, an acute bout of exercise is shown to suppress post-exercise appetite, yet limited research has examined this response in women. The purpose of this study was to investigate the effect of exercise intensity on appetite and gut hormone responses in endurance-trained women. Highly-trained women (n = 15, 18–40 years, 58.4 ± 6.4 kg, VO2MAX = 55.2 ± 4.3 mL/kg/min completed isocaloric bouts (500 kcals or 2093 kJ of moderate-intensity (MIE, 60% VO2MAX and high-intensity (HIE, 85% VO2MAX treadmill running at the same time of day, following a similar 48-h diet/exercise period, and at least 1-week apart. Blood was drawn pre-exercise (baseline, immediately post-exercise and every 20-min for the next 60-min. Plasma concentrations of acylated ghrelin, PYY3–36, GLP-1 and subjective appetite ratings via visual analog scale (VAS were assessed at each time point. Acylated ghrelin decreased (p = 0.014 and PYY3–36 and GLP-1 increased (p = 0.036, p < 0.0001 immediately post-exercise, indicating appetite suppression. VAS ratings of hunger and desire to eat decreased immediately post-exercise (p = 0.0012, p = 0.0031, respectively, also indicating appetite suppression. There were no differences between exercise intensities for appetite hormones or VAS. Similar to males, post-exercise appetite regulatory hormones were altered toward suppression in highly-trained women and independent of energy cost of exercise. Results are important for female athletes striving to optimize nutrition for endurance performance.

  10. RELATIONSHIP BETWEEN BODY BUILD AND ENDURANCE ON TREADMILL EXERCISES

    Directory of Open Access Journals (Sweden)

    Hemalathadevi

    2015-04-01

    Full Text Available INTRODUCTION: The type of the body build, efficacy of energy and oxygen supply mechanisms and utilization are the chief determinants of various forms of exertional endurance and achievement in various sporting activities. Therefore, the relationship between these varia bles of physique, fuel supply and aerobic capacity 6 and the endurance on treadmill stress test are chosen for study. MATERIALS & METHODS: Two groups (20 each of subjects (18 - 20 years were chosen based on body weight differences 9 60 kg BW for the study. They were further sub grouped based on BMI. DISCUSSION: When the body mass Index (BMI is at the range of 20 - 25, the endurance was better. However, when the BMI increased to very high value like 30, the endurance decreased. Such individual s with disproportionally high body weight could not endure a longer duration of exercise. This perhaps may be explained on the ground that such very high weight individuals (BMI > 30 may have more body fat than muscles. Excess body fat is dead weight that adds directly to the energy cost of running. In both groups of individuals with BMI of 20 or slightly above could run for longer periods than at extreme lower or higher ends of the BMI scale. OBSERVATIONS: The subjects with greater BMI could run for great er length of times, greater distances and achieved greater METs, glucose utilization and oxygen usage (aerobic capacity. The percentage of oxygen saturation (Pulse oxymetry after exercise fell to a greater degree in high body mass (BMI subjects indicati ng better cardio pulmonary function and greater degree of oxygen utilization. Finally, the resting heart rate and magnitude of heart rate rise during exercise are found to be somewhat lower in high body mass index subjects

  11. Endurance cycling results in extreme environments

    Science.gov (United States)

    Guertin, S. M.; Nguyen, D. N.; Scheick, L. Z.

    2003-01-01

    A new test bed for life testing flash memories in extreme environments is introducted. the test bed is based on a state-of-the-art development board. Since space applications often desire state-of-the-art devices, such a basis seems appropriate. Comparison of this tester to other such systems, including those with data presented here in the past is made. Limitations of different testers for varying applications are discussed. Recently developed data, using this test bed is also presented.

  12. Fire Endurance Testing of Fiberglass Piping

    Science.gov (United States)

    1992-04-01

    explosion . A computer data acquisition system was used to record the various channels of test data. Color video cameras, an infrared camera, and 35 mm...sample included a bolted flanged coupling. One of the copper-nickel samples had a brazed sleeve-type coupling and the other had a Staub mechanical...FGP of the types tested. Pipe deflections were within IACS limits. 8. An explosion hazard exists when sealed pipe samples are exposed to fire. If the

  13. The miRNA Plasma Signature in Response to Acute Aerobic Exercise and Endurance Training

    DEFF Research Database (Denmark)

    Nielsen, Søren; Åkerström, Thorbjörn; Rinnov, Anders

    2014-01-01

    the miRNA signature in human plasma in response to acute exercise and chronic endurance training by utilizing a novel methodological approach. RNA was isolated from human plasma collected from young healthy men before and after an acute endurance exercise bout and following 12 weeks of endurance training...

  14. Endurance training in patients with schizophrenia and healthy controls: differences and similarities.

    Science.gov (United States)

    Keller-Varady, Katriona; Hasan, Alkomiet; Schneider-Axmann, Thomas; Hillmer-Vogel, Ursula; Adomßent, Björn; Wobrock, Thomas; Schmitt, Andrea; Niklas, Andree; Falkai, Peter; Malchow, Berend

    2016-08-01

    The aims were to examine the feasibility of and adaptations to endurance training in persons diagnosed with schizophrenia and to address the question whether the principles and beneficial effects of endurance training established in the healthy population apply also to patients with schizophrenia. In this controlled interventional study, 22 patients with schizophrenia and 22 healthy controls performed a standardized aerobic endurance training on bicycle ergometers over 12 weeks. Another group of 21 patients with schizophrenia played table soccer. Endurance capacity was measured with incremental cycle ergometry before and after the intervention and 3 months later. A specific set of outcome parameters was defined. The training stimuli can be assumed to be similar in both endurance groups. Endurance capacity improved significantly in the endurance groups, but not in the table soccer group. Patients and healthy controls showed comparable adaptations to endurance training, as assessed by physical working capacity and maximal achieved power. Differences were found in changes of performance at a lactate concentration of 3 mmol/l. Endurance training was feasible and effective in both groups. The principles and types of training that are usually applied to healthy controls need to be verified in patients with schizophrenia. Nevertheless, patients benefited from endurance training in terms of improvement of endurance capacity and reduction in the baseline deficit in comparison with healthy controls. Therefore, endurance training should be implemented in future therapy programs. These programs need to pay special attention to the differences between patients with schizophrenia and healthy controls.

  15. OVERTRAINING IN ENDURANCE ATHLETES - A BRIEF REVIEW

    NARCIS (Netherlands)

    LEHMANN, M; FOSTER, C; KEUL, J

    Overtraining is an imbalance between training and recovery, exercise and exercise capacity. stress and stress tolerance. Stress is the sum of training and nontraining stress factors. Peripheral (short-term overtraining, STO) or peripheral and central fatigue may result (long-term overtraining, LTO).

  16. OVERTRAINING IN ENDURANCE ATHLETES - A BRIEF REVIEW

    NARCIS (Netherlands)

    LEHMANN, M; FOSTER, C; KEUL, J

    1993-01-01

    Overtraining is an imbalance between training and recovery, exercise and exercise capacity. stress and stress tolerance. Stress is the sum of training and nontraining stress factors. Peripheral (short-term overtraining, STO) or peripheral and central fatigue may result (long-term overtraining, LTO).

  17. Prevalence and risk factors for allergic rhinitis in two resource-limited settings in Peru with disparate degrees of urbanization

    Science.gov (United States)

    Baumann, L. M.; Romero, K. M.; Robinson, C. L.; Hansel, N. N.; Gilman, R. H.; Hamilton, R. G.; Lima, J. J.; Wise, R. A.; Checkley, W.

    2017-01-01

    Summary Background Allergic rhinitis is a disease with a high global disease burden, but risk factors that contribute to this condition are not well understood. Objective To assess the prevalence and risk factors of allergic rhinitis in two Peruvian populations with disparate degrees of urbanization. Methods We conducted a population-based, cross-sectional study on 1441 children aged 13–15 years at enrollment (mean age 14.9 years, 51% boys) to investigate the prevalence of allergic disease. We used a standardized, Spanish validated questionnaire to determine the prevalence of allergic rhinitis and asked about sociodemographics and family history of allergies. Children also underwent spirometry, exhaled nitric oxide, allergy skin testing to 10 common household allergens and provided a blood sample for measurement of 25OH vitamin D and total serum IgE. Results Overall prevalence of allergic rhinitis was 18% (95% CI 16% to 20%). When stratified by site, the prevalence of allergic rhinitis was 23% Lima vs. 13% in Tumbes (P eczema vs. 17% of those without eczema (P < 0.001). Important risk factors for allergic rhinitis were parental rhinitis (adjusted OR = 3.0, 95% CI 1.9–4.7 for 1 parent and adjusted OR = 4.4, 95% CI 1.5–13.7 for 2 parents); allergic sensitization to common household aeroallergens (1.6, 1.1–2.3); being overweight (1.5, 1.0–2.3); exhaled nitric oxide ≥20 ppb (1.9, 1.3–2.7); and total serum IgE ≥ 95th percentile (2.4, 1.2–4.8). Population attributable risk of important factors for allergic rhinitis were 25% for high exhaled nitric oxide, 22% for allergic sensitization to common household aeroallergens, 22% for paternal rhinitis, 10% for being overweight and 7% for an elevated total serum IgE. Conclusion and Clinical Relevance Allergic rhinitis was prevalent in both settings, and important risk factors include elevated exhaled nitric oxide, allergic sensitization to common household aeroallergens, parental rhinitis, being overweight and

  18. Segment boundaries of the adult rat epididymis limit interstitial signaling by potential paracrine factors and segments lose differential gene expression after efferent duct ligation

    Institute of Scientific and Technical Information of China (English)

    Terry T. Turner; Daniel S. Johnston; Scott A. Jelinsky; Jose L. Tomsig; Joshua N. Finger

    2007-01-01

    The epididymis is divided into caput, corpus and cauda regions, organized into intraregional segments separated by connective tissue septa (CTS). In the adult rat and mouse these segments are highly differentiated. Regulation of these segments is by endocrine, lumicrine and paracrine factors, the relative importance of which remains under investigation. Here, the ability of the CTS to limit signaling in the interstitial compartment is reviewed as is the effect of 15 days of unilateral efferent duct ligation (EDL) on ipsilateral segmental transcriptional profiles. Inter-segmental microperifusions of epidermal growth factor (EGF), vascular endothelial growth factor (VEGFA) and fibroblast growth factor 2 (FGF2) increased phosphorylation of mitogen activated protein kinase (MAPK) in segments 1 and 2 of the rat epididymis and the effects of all factors were limited by the CTS separating the segments. Microarray analysis of segmental gene expression determined the effect of 15 days of unilateral EDL on the transcriptome-wide gene expression of rat segments 1-4. Over 11 000 genes were expressed in each of the four segments and over 2 000 transcripts in segment 1 responded to deprivation of testicular lumicrine factors. Segments 1 and 2 of control tissues were the most transcriptionally different and EDL had its greatest effects there. In the absence of lumicrine factors, all four segments regressed to a transcriptionally undifferentiated state, consistent with the less differentiated histology. Deprivation of lumicrine factors could stimulate an individual gene's expression in some segments yet suppress it in others. Such results reveal a higher complexity of the regulation of rat epididymal segments than that is generally appreciated.

  19. Factors Limiting Microbial Growth and Activity at a Proposed High-Level Nuclear Repository, Yucca Mountain, Nevada

    OpenAIRE

    Kieft, T. L.; Kovacik, W. P.; Ringelberg, D B; White, D. C.; Haldeman, D. L.; Amy, P S; Hersman, L. E.

    1997-01-01

    As part of the characterization of Yucca Mountain, Nev., as a potential repository for high-level nuclear waste, volcanic tuff was analyzed for microbial abundance and activity. Tuff was collected aseptically from nine sites along a tunnel in Yucca Mountain. Microbial abundance was generally low: direct microscopic cell counts were near detection limits at all sites (3.2 x 10(sup4) to 2.0 x 10(sup5) cells g(sup-1) [dry weight]); plate counts of aerobic heterotrophs ranged from 1.0 x 10(sup1) ...

  20. Assessing streamflow characteristics as limiting factors on benthic invertebrate assemblages in streams across the western United States

    Science.gov (United States)

    Konrad, C.P.; Brasher, A.M.D.; May, J.T.

    2008-01-01

    1. Human use of land and water resources modifies many streamflow characteristics, which can have significant ecological consequences. Streamflow and invertebrate data collected at 111 sites in the western U.S.A. were analysed to identify streamflow characteristics (magnitude, frequency, duration, timing and variation) that are probably to limit characteristics of benthic invertebrate assemblages (abundance, richness, diversity and evenness, functional feeding groups and individual taxa) and, thus, would be important for freshwater conservation and restoration. Our analysis investigated multiple metrics for each biological and hydrological characteristic, but focuses on 14 invertebrate metrics and 13 streamflow metrics representing the key associations between streamflow and invertebrates.

  1. LXY6090 – a novel manassantin A derivative – limits breast cancer growth through hypoxia-inducible factor-1 inhibition

    OpenAIRE

    Lai, Fangfang; Liu, Qian; LIU, Xiaoyu; Ji, Ming; Xie, Ping; Chen, Xiaoguang

    2016-01-01

    Hypoxia-inducible factor-1 (HIF-1) represents a novel antitumor target owing to its involvement in vital processes considered hallmarks of cancer phenotypes. Manassantin A (MA) derived from Saururus cernuus has been reported as a selective HIF-1 inhibitor. Herein, the structure of MA was optimized to achieve new derivatives with simple chemical properties while retaining its activity. LXY6090 was designed to replace the central tetrahydrofuran moiety of MA with a cyclopentane ring and was ide...

  2. Effect of sex differences on human MEF2 regulation during endurance exercise

    DEFF Research Database (Denmark)

    Vissing, Kristian; McGee, Sean L; Roepstorff, Carsten

    2008-01-01

    . The primary purpose of this study, therefore, was to investigate the protein signaling of MEF2 regulatory pathway components at rest and during 90 min of bicycling exercise at 60% Vo(2peak) in healthy, moderately trained men (n = 8) and women (n = 9) to elucidate the potential role of these proteins......Women exhibit an enhanced capability for lipid metabolism during endurance exercise compared with men. The underlying regulatory mechanisms behind this sex-related difference are not well understood but may comprise signaling through a myocyte enhancer factor 2 (MEF2) regulatory pathway...... in substrate utilization during exercise. A secondary purpose was to screen for mRNA expression of MEF2 isoforms and myogenic regulatory factor (MRF) family members of transcription factors at rest and during exercise. Muscle biopsies were obtained before and immediately after exercise. Nuclear AMP...

  3. Meaningful learning: The essential factor for conceptual change in limited or inappropriate propositional hierarchies leading to empowerment of learners

    Science.gov (United States)

    Novak, Joseph D.

    2002-07-01

    The construction and reconstruction of meanings by learners requires that they actively seek to integrate new knowledge with knowledge already in their cognitive structure. Ausubel's assimilation theory of cognitive learning has been shown to be effective in guiding research and instructional design to facilitate meaningful learning (Ausubel, The psychology of meaningful verbal learning, New York: Grune and Stratton, 1963; Educational psychology: A cognitive view, New York: Holt, Rinehart and Winston, 1968; The acquisition and retention of knowledge, Dordrecht: Kluwer, 2000). Gowin's Vee heuristic has been employed effectively to aid teachers and students in understanding the constructed nature of knowledge (Gowin, Educating, Ithaca, NY: Cornell University Press, 1981). Situated learning occurs when learning is by rote or at a lower level of meaningful learning. Concept mapping has been used effectively to aid meaningful learning with resulting modification of student's knowledge structures. When these knowledge structures are limited or faulty in some way, they may be referred to as Limited or Inappropriate Propositional Hierarchies (LIPH's). Conceptual change, or more accurately conceptual reconstrution, requires meaningful learning to modify LIPH's. Collaborative group learning facilitates meaningful learning and new knowledge construction. World-wide economic changes are forcing major changes in business and industry placing a premium on the power and value of knowledge and new knowledge production. These changes require changes in school and university education that centers on the nature and power of meaningful learning. New computer tools are available to facilitate teaching activities targeted at modifying LIPH's, and aiding meaningful learning in general.

  4. Regulation of the STARS signaling pathway in response to endurance and resistance exercise and training.

    Science.gov (United States)

    Lamon, Séverine; Wallace, Marita A; Stefanetti, Renae J; Rahbek, Stine K; Vendelbo, Mikkel H; Russell, Aaron P; Vissing, Kristian

    2013-09-01

    The striated muscle activator of Rho signaling (STARS) protein and members of its downstream signaling pathway, including myocardin-related transcription factor-A (MRTF-A) and SRF, are increased in response to prolonged resistance exercise training but also following a single bout of endurance cycling. The aim of the present study was to measure and compare the regulation of STARS, MRTF-A and SRF mRNA and protein following 10 weeks of endurance training (ET) versus resistance training (RT), as well as before and following a single bout of endurance (EE) versus resistance exercise (RE). Following prolonged training, STARS, MRTF-A and SRF mRNA levels were all increased by similar magnitude, irrespective of training type. In the training-habituated state, STARS mRNA increased following a single-bout RE when measured 2.5 and 5 h post-exercise and had returned to resting level by 22 h following exercise. MRTF-A and SRF mRNA levels were decreased by 2.5, 5, and 22 h following a single bout of RE and EE exercise when compared to their respective basal levels, with no significant difference seen between the groups at any of the time points. No changes in protein levels were observed following the two modes of exercise training or a single bout of exercise. This study demonstrates that the stress signals elicited by ET and RT result in a comparable regulation of members of the STARS pathway. In contrast, a single bout of EE and RE, performed in the trained state, elicit different responses. These observations suggest that in the trained state, the acute regulation of the STARS pathway following EE or RE may be responsible for exercise-specific muscle adaptations.

  5. Short-duration intermittent hypoxia enhances endurance capacity by improving muscle fatty acid metabolism in mice.

    Science.gov (United States)

    Suzuki, Junichi

    2016-04-01

    This study was designed to (1) investigate the effects of acute short-duration intermittent hypoxia on musclemRNAand microRNAexpression levels; and (2) clarify the mechanisms by which short-duration intermittent hypoxia improves endurance capacity. Experiment-1: Male mice were subjected to either acute 1-h hypoxia (12% O2), acute short-duration intermittent hypoxia (12% O2for 15 min, room air for 10 min, 4 times, Int-Hypo), or acute endurance exercise (Ex). The expression of vascular endothelial growth factor-AmRNAwas significantly greater than the control at 0 h post Ex and 6 h post Int-Hypo in the deep red region of the gastrocnemius muscle. miR-16 expression levels were significantly lower at 6 and 10 h post Int-Hypo. Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α)mRNAlevels were significantly greater than the control at 3 h post Ex and 6 h post Int-Hypo. miR-23a expression levels were lower than the control at 6-24 h post Int-Hypo. Experiment-2: Mice were subjected to normoxic exercise training with or without intermittent hypoxia for 3 weeks. Increases in maximal exercise capacity were significantly greater by training with short-duration intermittent hypoxia (IntTr) than without hypoxia. Both 3-Hydroxyacyl-CoA-dehydrogenase and total carnitine palmitoyl transferase activities were significantly enhanced in IntTr. Peroxisome proliferator-activated receptor delta andPGC-1α mRNAlevels were both significantly greater in IntTr than in the sedentary controls. These results suggest that exercise training under normoxic conditions with exposure to short-duration intermittent hypoxia represents a beneficial strategy for increasing endurance performance by enhancing fatty acid metabolism in skeletal muscle.

  6. Effects of eccentric cycling and endurance training versus low cadence cycling and endurance training on muscle strength and cycling performance in trained individuals

    OpenAIRE

    Eidsheim, Hedda Øyeflaten

    2016-01-01

    Background: Recent studies have shown a positive effect of concurrent strength and endurance training on performance in cycling. Still, few studies have investigated the effect of eccentric cycling (ECC) and low cadence cycling (LCC) on muscle strength and determinants of cycling performance. Aim: Compare the effect of concurrent ECC and endurance training with concurrent LCC and endurance training on strength development, muscle thickness, and cycling performance in trained...

  7. Association of Chronic Obstructive Pulmonary Disease With Increased Confusion or Memory Loss and Functional Limitations Among Adults in 21 States, 2011 Behavioral Risk Factor Surveillance System

    Directory of Open Access Journals (Sweden)

    Kurt J. Greenlund, PhD

    2016-01-01

    Full Text Available Introduction Chronic obstructive pulmonary disease (COPD is associated with cognitive impairment, but consequences of this association on a person’s functional limitations are unclear. We examined the association between COPD and increased confusion and memory loss (ICML and functional limitations among adults with COPD. Methods We studied adults aged 45 years or older in 21 states who participated in the 2011 Behavioral Risk Factor Surveillance System (n = 102,739. Presence of COPD was based on self-reported physician diagnosis. ICML was based on self-report that confusion or memory loss occurred more often or worsened during the prior year. ICML-associated difficulties were defined as giving up household chores and former activities, decreased ability to work or engage in social activities, or needing help from family or friends during the prior year due to ICML. General limitations were defined as needing special equipment as a result of a health condition, having had activity limitations for 2 weeks or more in the prior month, or being unable to work. Multivariable models were adjusted for demographics, health behaviors or conditions, and frequent mental distress. Results COPD was reported by 9.3% of adults. ICML was greater among those with COPD than among those without COPD (25.8% vs 11%; adjusted prevalence ratio [aPR], 1.48; 95% confidence interval [CI], 1.32%–1.66%. People with COPD, either with or without ICML, were more likely than those without COPD to report general functional limitations. Among people reporting ICML, those with COPD were more likely to report interference with work or social activities than those without COPD (aPR, 1.17; 95% CI, 1.01%–1.36%. Conclusion Functional limitations were greater among those with COPD than among those without, and ICML may further affect these limitations. Results from our study can inform future studies of self- management and functional limitations for people with COPD.

  8. Plant size and abiotic factors determine the intra-specific variation in the multi-stemmed architecture of Prunus lusitanica in the Northeast limit of its global distribution

    Directory of Open Access Journals (Sweden)

    A. Muñoz Costa

    2013-12-01

    Full Text Available Aim of study: The present work provides novel insights on factors (either intrinsic or extrinsic that trigger sprouting in woody species living at range margins. We aim to explain the inter-individual variability in the multi-stemmed architecture of Prunus lusitanica L., an Iberian evergreen relict tree related to the Tertiary flora.Area of study: Northeastern Mediterranean mountains of the Iberian Peninsula, the Northeast limit of the global distribution of the species.Material and Methods: We gathered data on two modes of vegetative reproduction, basal and layering sprouts, in 288 clumps of Prunus lusitanica from four populations. We modeled and analyzed the effect of environmental factors (topography, canopy cover, soil moisture and disturbances and plant size (diameter at breast height on sprouting by means of Generalized Linear Model and other statistical approaches.Main results: Plant size arises as the principal factor to explain the variability of the numbers of both types of sprouts yet it is not a trigger factor. Natural and anthropogenic disturbances promote basal and layering shoots, while tree canopy is mainly relevant for basal shoots, and slope and soil moisture are significant factors for layering shoots.Research highlights: The multi-stemmed architecture of P. lusitanica at the Northeastern limit of its worldwide distribution is triggered by local environmental factors and disturbances. Each external factor shows different levels of influence on the variability and type of vegetative reproduction yet the intensity of the response is driven by the size of the largest trunk of each clump.Key words: vegetative reproduction; sprouting; disturbances; woody plants; relict tree; subtropical; Iberian Peninsula.

  9. A Systematic Review of the Association Between Physical Fitness and Musculoskeletal Injury Risk: Part 1 - Cardiorespiratory Endurance.

    Science.gov (United States)

    Lisman, Peter; de la Motte, Sarah J; Gribbin, Timothy C; Jaffin, Dianna Purvis; Murphy, Kaitlin; Deuster, Patricia A

    2017-02-13

    Musculoskeletal injuries (MSK-I) are a significant health problem for both military and athletic populations. Research indicates MSK-I is associated with physical fitness; however, the association between specific components of physical fitness and MSK-I in military and athletic populations has not been systematically examined. Our goal was to systematically review the literature to provide a best evidence synthesis on the relationship between components of physical fitness and MSK-I risk in military and civilian athletic populations. This first of three manuscripts focuses on cardiorespiratory endurance (CRE). MEDLINE, EBSCO, EMBASE, and the Defense Technical Information Center were searched for original studies published from 1970 through 2015 that examined associations between physical fitness and MSK-I. Forty-nine of 4,229 citations met our inclusion criteria. Primary findings indicate there is 1) strong evidence that poor performance on a set distance run for time is a predictor for MSK-I risk in both genders; 2) strong evidence that poor performance on timed shuttle runs is a predictor for MSK-I risk in males; 3) moderate evidence in males and limited evidence in females that poor performance on a timed step test is a predictor of MSK-I risk; and 4) limited or insufficient evidence that poor performance on the Cooper run test, maximal and submaximal aerobic graded exercise tests, and the Conconi test are predictors of MSK-I risk in males and/or females. Several measures of CRE are risk factors for training-related MSK-I in military and civilian athletic populations, indicating CRE may be an important measure for MSK-I risk stratification.

  10. Speed endurance training is a powerful stimulus for physiological adaptations and performance improvements of athletes

    DEFF Research Database (Denmark)

    Iaia, F. M.; Bangsbo, Jens

    2010-01-01

    performance during longer events, e.g. 40 K cycling and 10 K running. Athletes in team sports involving intense exercise actions and endurance aspects can also benefit from performing speed endurance training. These improvements don't appear to depend on changes in maximum oxygen uptake (VO2max), muscle......The present article reviews the physiological and performance effects of speed endurance training consisting of exercise bouts at near maximal intensities in already trained subjects. Despite a reduction in training volume, speed endurance training of endurance-trained athletes can maintain...

  11. The Research on the Effect of the Food with Different Glycaemic Index and Glycaemic Load on the Immunity of Endurance Athletes

    Science.gov (United States)

    Li, Dongmei

    2015-01-01

    For studying the effect of eating the food containing carbohydrates with different glycaemic index and glycaemic load 2 hours before athletics on the exercise tolerance and immune function, select 10 men long-distance endurance athletes, use not completely random balance repeated testing methods, randomized complete the three endurance tests. And each test interval is not less than seven days. The results suggest that there is no apparent effect of eating the food containing carbohydrates with different glycaemic index and glycaemic load 2 hours before athletics on the exercise tolerance and immune function. Compared with the glycaemic index and glycaemic load of food, the carbohydrate content of the diet before athletics may be the more important factor affecting the immune response in endurance sports. PMID:26998178

  12. The Research on the Effect of the Food with Different Glycaemic Index and Glycaemic Load on the Immunity of Endurance Athletes.

    Science.gov (United States)

    Li, Dongmei

    2015-01-01

    For studying the effect of eating the food containing carbohydrates with different glycaemic index and glycaemic load 2 hours before athletics on the exercise tolerance and immune function, select 10 men long-distance endurance athletes, use not completely random balance repeated testing methods, randomized complete the three endurance tests. And each test interval is not less than seven days. The results suggest that there is no apparent effect of eating the food containing carbohydrates with different glycaemic index and glycaemic load 2 hours before athletics on the exercise tolerance and immune function. Compared with the glycaemic index and glycaemic load of food, the carbohydrate content of the diet before athletics may be the more important factor affecting the immune response in endurance sports.

  13. Utilization of health services in a resource-limited rural area in Kenya: Prevalence and associated household-level factors

    Science.gov (United States)

    Ngugi, Anthony K.; Agoi, Felix; Mahoney, Megan R.; Lakhani, Amyn; Mang’ong’o, David; Nderitu, Esther; Armstrong, Robert; Macfarlane, Sarah

    2017-01-01

    Background and methods Knowledge of utilization of health services and associated factors is important in planning and delivery of interventions to improve health services coverage. We determined the prevalence and factors associated with health services utilization in a rural area of Kenya. Our findings inform the local health management in development of appropriately targeted interventions. We used a cluster sample survey design and interviewed household key informants on history of illness for household members and health services utilization in the preceding month. We estimated prevalence and performed random effects logistic regression to determine the influence of individual and household level factors on decisions to utilize health services. Results and conclusions 1230/6,440 (19.1%, 95% CI: 18.3%-20.2%) household members reported an illness. Of these, 76.7% (95% CI: 74.2%-79.0%) sought healthcare in a health facility. The majority (94%) of the respondents visited dispensary-level facilities and only 60.1% attended facilities within the study sub-counties. Of those that did not seek health services, 43% self-medicated by buying non-prescription drugs, 20% thought health services were too costly, and 10% indicated that the sickness was not serious enough to necessitate visiting a health facility. In the multivariate analyses, relationship to head of household was associated with utilization of health services. Relatives other than the nuclear family of the head of household were five times less likely to seek medical help (Odds Ratio 0.21 (95% CI: 0.05–0.87)). Dispensary level health facilities are the most commonly used by members of this community, and relations at the level of the household influence utilization of health services during an illness. These data enrich the perspective of the local health management to better plan the allocation of healthcare resources according to need and demand. The findings will also contribute in the development of

  14. The Manipulation of Pace within Endurance Sport

    Science.gov (United States)

    Skorski, Sabrina; Abbiss, Chris R.

    2017-01-01

    In any athletic event, the ability to appropriately distribute energy is essential to prevent premature fatigue prior to the completion of the event. In sport science literature this is termed “pacing.” Within the past decade, research aiming to better understand the underlying mechanisms influencing the selection of an athlete's pacing during exercise has dramatically increased. It is suggested that pacing is a combination of anticipation, knowledge of the end-point, prior experience and sensory feedback. In order to better understand the role each of these factors have in the regulation of pace, studies have often manipulated various conditions known to influence performance such as the feedback provided to participants, the starting strategy or environmental conditions. As with all research there are several factors that should be considered in the interpretation of results from these studies. Thus, this review aims at discussing the pacing literature examining the manipulation of: (i) energy expenditure and pacing strategies, (ii) kinematics or biomechanics, (iii) exercise environment, and (iv) fatigue development. PMID:28289392

  15. Simulating the physiology of athletes during endurance sports events: modelling human energy conversion and metabolism.

    Science.gov (United States)

    van Beek, Johannes H G M; Supandi, Farahaniza; Gavai, Anand K; de Graaf, Albert A; Binsl, Thomas W; Hettling, Hannes

    2011-11-13

    The human physiological system is stressed to its limits during endurance sports competition events. We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We calculated heat transfer by conduction and blood flow inside the body, and heat transfer from the skin by radiation, convection and sweat evaporation, resulting in temperature changes in 25 body compartments. We simulated a mountain time trial to Alpe d'Huez during the Tour de France. To approach the time realized by Lance Armstrong in 2004, very high oxygen uptake must be sustained by the simulated cyclist. Temperature was predicted to reach 39°C in the brain, and 39.7°C in leg muscle. In addition to the macroscopic simulation, we analysed the buffering of bursts of high adenosine triphosphate hydrolysis by creatine kinase during cyclical muscle activity at the biochemical pathway level. To investigate the low oxygen to carbohydrate ratio for the brain, which takes up lactate during exercise, we calculated the flux distribution in cerebral energy metabolism. Computational modelling of the human body, describing heat exchange and energy metabolism, makes simulation of endurance sports events feasible.

  16. Altitude training for elite endurance athletes: A review for the travel medicine practitioner.

    Science.gov (United States)

    Flaherty, Gerard; O'Connor, Rory; Johnston, Niall

    2016-01-01

    High altitude training is regarded as an integral component of modern athletic preparation, especially for endurance sports such as middle and long distance running. It has rapidly achieved popularity among elite endurance athletes and their coaches. Increased hypoxic stress at altitude facilitates key physiological adaptations within the athlete, which in turn may lead to improvements in sea-level athletic performance. Despite much research in this area to date, the exact mechanisms which underlie such improvements remain to be fully elucidated. This review describes the current understanding of physiological adaptation to high altitude training and its implications for athletic performance. It also discusses the rationale and main effects of different training models currently employed to maximise performance. Athletes who travel to altitude for training purposes are at risk of suffering the detrimental effects of altitude. Altitude illness, weight loss, immune suppression and sleep disturbance may serve to limit athletic performance. This review provides an overview of potential problems which an athlete may experience at altitude, and offers specific training recommendations so that these detrimental effects are minimised. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. High Altitude Long Endurance UAV Analysis of Alternatives and Technology Requirements Development

    Science.gov (United States)

    Nickol, Craig L.; Guynn, Mark D.; Kohout, Lisa L.; Ozoroski, Thomas A.

    2007-01-01

    An Analysis of Alternatives and a Technology Requirements Study were conducted for two mission areas utilizing various types of High Altitude Long Endurance (HALE) Unmanned Aerial Vehicles (UAV). A hurricane science mission and a communications relay mission provided air vehicle requirements which were used to derive sixteen potential HALE UAV configurations, including heavier-than-air (HTA) and lighter-than-air (LTA) concepts with both consumable fuel and solar regenerative propulsion systems. A HTA diesel-fueled wing-body-tail configuration emerged as the preferred concept given near-term technology constraints. The cost effectiveness analysis showed that simply maximizing vehicle endurance can be a sub-optimum system solution. In addition, the HTA solar regenerative configuration was utilized to perform both a mission requirements study and a technology development study. Given near-term technology constraints, the solar regenerative powered vehicle was limited to operations during the long days and short nights at higher latitudes during the summer months. Technology improvements are required in energy storage system specific energy and solar cell efficiency, along with airframe drag and mass reductions to enable the solar regenerative vehicle to meet the full mission requirements.

  18. Exercise addiction risk and health in male and female amateur endurance cyclists.

    Science.gov (United States)

    Mayolas-Pi, Carmen; Simón-Grima, Javier; Peñarrubia-Lozano, Carlos; Munguía-Izquierdo, Diego; Moliner-Urdiales, Diego; Legaz-Arrese, Alejandro

    2017-03-01

    Background and aims To determine the relationship between the risk of exercise addiction (REA) and health status in amateur endurance cyclists. Methods In 859 (751 men and 108 women) cyclists and 718 inactive subjects (307 men and 411 women), we examined the REA (Exercise Addiction Inventory), training status (volume, frequency, experience, and performance), socioeconomic status, quality of life (QoL) (SF-12), quality of sleep (Pittsburgh Sleep Quality Index), anxiety and depression (Hospital Anxiety and Depression Scale), and cardiometabolic risk: body mass index, physical activity (International Physical Activity Questionnaire), physical condition (International Fitness Scale), adherence to the Mediterranean diet (Mediterranean Diet Adherence Screener), alcohol and tobacco consumption. Results In total, 17% of the cyclists showed evidence of REA and 83% showed low REA. REA occurred independent of age, sex, training, and socioeconomic status (all ps > .05). Regardless of REA, the cyclists displayed a better physical QoL and a lower cardiometabolic risk than the inactive subjects (all ps Addiction × Sex interaction in the other analyzed variables. Conclusion Our results suggest that an increased prevalence of REA limits the benefits that amateur endurance cycling has on mental health and quality of sleep.

  19. The linewidth enhancement factor of intersubband lasers: From a two-level limit to gain without inversion conditions

    Science.gov (United States)

    Pereira, M. F.

    2016-11-01

    The linewidth enhancement (α factor) due to fluctuations in the refractive index induced by carrier fluctuations of intersubband lasers was initially expected to be zero. However, values ranging from -0.5 to 3 have been found experimentally. This paper resolves this controversy showing that counter rotating terms, usually ignored in simulations, are the actual fundamental origin of nonzero α at peak gain even without the inclusion of nonparabolicity and manybody effects, which are however needed to explain negative values. For laser without inversion conditions, significant as a potential out of the box solution for the elusive room temperature operation of terahertz lasers, α is found to be larger, but still at the same order of magnitude of conventional inverted medium lasers, thus ensuring their applicability to a huge number of spectroscopic applications that require sharp laser linewidths.

  20. Factors limiting industrial development in peripheral regions of developing countries: a case study of kedah state, peninsular Malaysia

    Directory of Open Access Journals (Sweden)

    Morshidi Sirat

    2013-07-01

    Full Text Available Many developing countries, Malaysia included, have relied quite heavily on the policy of industrial decentralization to uplift the lagging economies of their peripheral regions. In Malaysia, the Malaysian Industrial Development Authorithy (MIDA - a federal agency - plays a major role in persuading foreign enterprises to locate in the periphery. In addition to MIDA there are plethora of state agencies which implement state industrial policy. Development officials, in their effort to attract more industries to their respective regions, work on the premise that certain locational factors are critical to investors locational decision- making process. Obviously, development officials have their own perceptions of the attractions and disadvantages of the periphery. This paper (a examines whether the officials have a good grasp of the industrialists dominant motives for selecting Kedah as production location, and (b discusses the implications for industrial development if officials assumptions do not concur with industrialists real reasons for selecting Kedah location.

  1. Plant nuclear factor Y (NF-Y) B subunits confer drought tolerance and lead to improved corn yields on water-limited acres.

    Science.gov (United States)

    Nelson, Donald E; Repetti, Peter P; Adams, Tom R; Creelman, Robert A; Wu, Jingrui; Warner, David C; Anstrom, Don C; Bensen, Robert J; Castiglioni, Paolo P; Donnarummo, Meghan G; Hinchey, Brendan S; Kumimoto, Roderick W; Maszle, Don R; Canales, Roger D; Krolikowski, Katherine A; Dotson, Stanton B; Gutterson, Neal; Ratcliffe, Oliver J; Heard, Jacqueline E

    2007-10-16

    Commercially improved crop performance under drought conditions has been challenging because of the complexity of the trait and the multitude of factors that influence yield. Here we report the results of a functional genomics approach that identified a transcription factor from the nuclear factor Y (NF-Y) family, AtNF-YB1, which acts through a previously undescribed mechanism to confer improved performance in Arabidopsis under drought conditions. An orthologous maize transcription factor, ZmNF-YB2, is shown to have an equivalent activity. Under water-limited conditions, transgenic maize plants with increased ZmNF-YB2 expression show tolerance to drought based on the responses of a number of stress-related parameters, including chlorophyll content, stomatal conductance, leaf temperature, reduced wilting, and maintenance of photosynthesis. These stress adaptations contribute to a grain yield advantage to maize under water-limited environments. The application of this technology has the potential to significantly impact maize production systems that experience drought.

  2. Ethylene Response Factor6 acts as a central regulator of leaf growth under water-limiting conditions in Arabidopsis.

    Science.gov (United States)

    Dubois, Marieke; Skirycz, Aleksandra; Claeys, Hannes; Maleux, Katrien; Dhondt, Stijn; De Bodt, Stefanie; Vanden Bossche, Robin; De Milde, Liesbeth; Yoshizumi, Takeshi; Matsui, Minami; Inzé, Dirk

    2013-05-01

    Leaf growth is a complex developmental process that is continuously fine-tuned by the environment. Various abiotic stresses, including mild drought stress, have been shown to inhibit leaf growth in Arabidopsis (Arabidopsis thaliana), but the underlying mechanisms remain largely unknown. Here, we identify the redundant Arabidopsis transcription factors ETHYLENE RESPONSE FACTOR5 (ERF5) and ERF6 as master regulators that adapt leaf growth to environmental changes. ERF5 and ERF6 gene expression is induced very rapidly and specifically in actively growing leaves after sudden exposure to osmotic stress that mimics mild drought. Subsequently, enhanced ERF6 expression inhibits cell proliferation and leaf growth by a process involving gibberellin and DELLA signaling. Using an ERF6-inducible overexpression line, we demonstrate that the gibberellin-degrading enzyme GIBBERELLIN 2-OXIDASE6 is transcriptionally induced by ERF6 and that, consequently, DELLA proteins are stabilized. As a result, ERF6 gain-of-function lines are dwarfed and hypersensitive to osmotic stress, while the growth of erf5erf6 loss-of-function mutants is less affected by stress. Besides its role in plant growth under stress, ERF6 also activates the expression of a plethora of osmotic stress-responsive genes, including the well-known stress tolerance genes STZ, MYB51, and WRKY33. Interestingly, activation of the stress tolerance genes by ERF6 occurs independently from the ERF6-mediated growth inhibition. Together, these data fit into a leaf growth regulatory model in which ERF5 and ERF6 form a missing link between the previously observed stress-induced 1-aminocyclopropane-1-carboxylic acid accumulation and DELLA-mediated cell cycle exit and execute a dual role by regulating both stress tolerance and growth inhibition.

  3. Resistance exercise, but not endurance exercise, induces IKKβ phosphorylation in human skeletal muscle of training-accustomed individuals

    DEFF Research Database (Denmark)

    Møller, Andreas Buch; Vendelbo, Mikkel Holm; Rahbek, Stine Klejs

    2013-01-01

    of repeated biopsy sampling on protein expression and phosphorylation was observed. In conclusion, resistance exercise, but not endurance exercise, increases IKKβ phosphorylation in trained human subjects, which support the idea that IKKβ can influence the activation of mTORC1 in human skeletal muscle.......The mammalian target of rapamycin complex 1 (mTORC1) is considered an important role in the muscular adaptations to exercise. It has been proposed that exercise-induced signaling to mTORC1 do not require classic growth factor PI3K/Akt signaling. Activation of IKKβ and the mitogen-activated protein...... following exercise. Previously, we demonstrated that mTOR is preferentially activated in response to resistance exercise compared to endurance exercise in trained individuals without concomitant activation of Akt. In the present study, we extended this investigation by examining IκB kinase complex (IKK...

  4. Endurance exercise training and diferuloyl methane supplement

    DEFF Research Database (Denmark)

    Roshan, Valiollah Dabidi; Hosseinzadeh, Somayeh; Mahjoub, Soleiman

    2013-01-01

    For many years it has been known that lead is life-threatening, not only as an air pollutant but also because of it has been associated with several conditions including degenerative disease of the nervous system. In the current study we investigated neuroprotection effects of exercise training and...... resulted in a significantly increase in the malondialdehyde (MDA) in plasma, but not in hippocampus. In addition, it led to significantly decreased brain-derived neurotrophic factor (BDNF) in hippocampus and total antioxidant capacity (TAC) levels, as compared to sham group. Treadmill running, curcumin...... supplementation, or both resulted in a significant decrease in MDA levels and significantly increased BDNF and TAC levels, as compared to lead acetate group. These results provide a rationale for an inhibitory role of curcumin and regular exercise in the attenuation of lead-induced neurotoxicity....

  5. Hypertrophic cardiomyopathy and ultra-endurance running - two incompatible entities?

    Directory of Open Access Journals (Sweden)

    Wilson Mathew G

    2011-11-01

    Full Text Available Abstract Regular and prolonged exercise is associated with increased left ventricular wall thickness that can overlap with hypertrophic cardiomyopathy (HCM. Differentiating physiological from pathological hypertrophy has important implications, since HCM is the commonest cause of exercise-related sudden cardiac death in young individuals. Most deaths have been reported in intermittent 'start-stop' sports such as football (soccer and basketball. The theory is that individuals with HCM are unable to augment stroke volume sufficiently to meet the demands of endurance sports and are accordingly 'selected-out' of participation in such events. We report the case of an ultra-endurance athlete with 25 years of > 50 km competitive running experience, with genetically confirmed HCM; thereby demonstrating that these can be two compatible entities.

  6. Born to run. Studying the limits of human performance

    Directory of Open Access Journals (Sweden)

    Murray Andrew

    2012-07-01

    Full Text Available Abstract It is recognised that regular physical activity and a high level of fitness are powerful predictors of positive health outcomes. There is a long and rich history of significant feats of human endurance with some, for example, the death of the first marathon runner, Pheidippides, associated with negative health outcomes. Early studies on endurance running used X-ray and interview techniques to evaluate competitors and comment on performance. Since then, comparatively few studies have looked at runners competing in distances longer than a marathon. Those that have, tend to show significant musculoskeletal injuries and a remarkable level of adaptation to this endurance load. The TransEurope Footrace Project followed ultra-endurance runners aiming to complete 4,500 Km of running in 64 days across Europe. This pioneering study will assess the impact of extreme endurance on human physiology; analysing musculoskeletal and other tissue/organ injuries, and the body's potential ability to adapt to extreme physiological stress. The results will be of interest not only to endurance runners, but to anyone interested in the limits of human performance. Please see related article: http://www.biomedcentral.com/1741-7015/10/78

  7. B cell-derived transforming growth factor-β1 expression limits the induction phase of autoimmune neuroinflammation

    Science.gov (United States)

    Bjarnadóttir, Kristbjörg; Benkhoucha, Mahdia; Merkler, Doron; Weber, Martin S.; Payne, Natalie L.; Bernard, Claude C. A.; Molnarfi, Nicolas; Lalive, Patrice H.

    2016-01-01

    Studies in experimental autoimmune encephalomyelitis (EAE), a murine model of multiple sclerosis (MS), have shown that regulatory B cells modulate the course of the disease via the production of suppressive cytokines. While data indicate a role for transforming growth factor (TGF)-β1 expression in regulatory B cell functions, this mechanism has not yet been tested in autoimmune neuroinflammation. Transgenic mice deficient for TGF-β1 expression in B cells (B–TGF-β1−/−) were tested in EAE induced by recombinant mouse myelin oligodendrocyte glycoprotein (rmMOG). In this model, B–TGF-β1−/− mice showed an earlier onset of neurologic impairment compared to their littermate controls. Exacerbated EAE susceptibility in B–TGF-β1−/− mice was associated with augmented CNS T helper (Th)1/17 responses. Moreover, selective B cell TGF-β1–deficiency increased the frequencies and activation of myeloid dendritic cells, potent professional antigen-presenting cells (APCs), suggesting that B cell-derived TGF-β1 can constrain Th1/17 responses through inhibition of APC activity. Collectively our data suggest that B cells can down-regulate the function of APCs, and in turn encephalitogenic Th1/17 responses, via TGF-β1, findings that may be relevant to B cell-targeted therapies. PMID:27708418

  8. LXY6090 - a novel manassantin A derivative - limits breast cancer growth through hypoxia-inducible factor-1 inhibition.

    Science.gov (United States)

    Lai, Fangfang; Liu, Qian; Liu, Xiaoyu; Ji, Ming; Xie, Ping; Chen, Xiaoguang

    2016-01-01

    Hypoxia-inducible factor-1 (HIF-1) represents a novel antitumor target owing to its involvement in vital processes considered hallmarks of cancer phenotypes. Manassantin A (MA) derived from Saururus cernuus has been reported as a selective HIF-1 inhibitor. Herein, the structure of MA was optimized to achieve new derivatives with simple chemical properties while retaining its activity. LXY6090 was designed to replace the central tetrahydrofuran moiety of MA with a cyclopentane ring and was identified as a potent HIF-1 inhibitor with an IC50 value of 4.11 nM. It not only inhibited the activity of HIF-1 in breast cancer cells but also downregulated the protein level of HIF-1α, which depended on von Hippel-Lindau for proteasome degradation. The related biological evaluation showed that the activity of HIF-1 target genes, VEGF and IGF-2, was decreased by LXY6090 in breast cancer cell lines. LXY6090 presented potent antitumor activity in vitro. Furthermore, LXY6090 showed in vivo anticancer efficacy by decreasing the HIF-1α expression in nude mice bearing MX-1 tumor xenografts. In conclusion, our data provide a basis for the future development of the novel compound LXY6090 as a potential therapeutic agent for breast cancer.

  9. LXY6090 – a novel manassantin A derivative – limits breast cancer growth through hypoxia-inducible factor-1 inhibition

    Science.gov (United States)

    Lai, Fangfang; Liu, Qian; Liu, Xiaoyu; Ji, Ming; Xie, Ping; Chen, Xiaoguang

    2016-01-01

    Hypoxia-inducible factor-1 (HIF-1) represents a novel antitumor target owing to its involvement in vital processes considered hallmarks of cancer phenotypes. Manassantin A (MA) derived from Saururus cernuus has been reported as a selective HIF-1 inhibitor. Herein, the structure of MA was optimized to achieve new derivatives with simple chemical properties while retaining its activity. LXY6090 was designed to replace the central tetrahydrofuran moiety of MA with a cyclopentane ring and was identified as a potent HIF-1 inhibitor with an IC50 value of 4.11 nM. It not only inhibited the activity of HIF-1 in breast cancer cells but also downregulated the protein level of HIF-1α, which depended on von Hippel–Lindau for proteasome degradation. The related biological evaluation showed that the activity of HIF-1 target genes, VEGF and IGF-2, was decreased by LXY6090 in breast cancer cell lines. LXY6090 presented potent antitumor activity in vitro. Furthermore, LXY6090 showed in vivo anticancer efficacy by decreasing the HIF-1α expression in nude mice bearing MX-1 tumor xenografts. In conclusion, our data provide a basis for the future development of the novel compound LXY6090 as a potential therapeutic agent for breast cancer. PMID:27445487

  10. Strength training improves cycling efficiency in master endurance athletes.

    Science.gov (United States)

    Louis, Julien; Hausswirth, Christophe; Easthope, Christopher; Brisswalter, Jeanick

    2012-02-01

    The purpose of this study was to test the effect of a 3-week strength training program of knee extensor muscles on cycling delta efficiency in master endurance athletes. Nine master (age 51.5 ± 5.5 years) and 8 young (age 25.6 ± 5.9 years) endurance athletes with similar training levels participated in this study. During three consecutive weeks, all the subjects were engaged in a strength training program of the knee extensor muscles. Every week, they performed three training sessions consist of 10 × 10 knee extensions at 70% of maximal repetition with 3 min rest between in a leg extension apparatus. Maximal voluntary contraction torque (MVC torque) and force endurance (End) were assessed before, after every completed week of training, and after the program. Delta efficiency (DE) in cycling was evaluated before and after the training period. Before the training period, MVC torque, End, and DE in cycling were significantly lower in masters than in young. The strength training induced a significant improvement in MVC torque in all the subjects, more pronounced in masters (+17.8% in masters vs. +5.9% in young, P < 0.05). DE in cycling also significantly increased after training in masters, whereas it was only a trend in young. A significant correlation (r = 0.79, P < 0.01) was observed between MVC torque and DE in cycling in masters. The addition of a strength training program for the knee extensor muscles to endurance-only training induced a significant improvement in strength and cycling efficiency in master athletes. This enhancement in muscle performance alleviated all the age-related differences in strength and efficiency.

  11. Nutritional habits among high-performance endurance athletes

    OpenAIRE

    Baranauskas, Marius; Stukas, Rimantas; Tubelis, Linas; Žagminas, Kęstutis; Šurkienė, Genė; Švedas, Edmundas; Giedraitis, Vincentas Rolandas; Dobrovolskij, Valerij; Abaravičius, Jonas Algis

    2015-01-01

    Background and objective: For athletes, the main purpose of nutrition is to ensure the compensation of increased energy consumption and the need for nutrients in the athlete's body, thereby enabling maximum adaptation to physical loads. The aim of this study was to determine the habits of highly trained endurance athletes depending on sports type, sex and age in order to improve the planning and management of the training of athletes using targeted measures. Materials and me...

  12. Speed, Strength and Endurance Training for Adolescent Footballers in Kenya

    OpenAIRE

    Igendia, Mikael

    2012-01-01

    The subject of this thesis was speed, strength and endurance training for adolescent footballers in Kenya. The commissioner of this work was the Football Kenya Federation (FKF). Football is a popular sport in Kenya, but the development of football in Kenya has been ineffective due to poor coaching standards, lack of information and inadequate facilities. This has also resulted in Kenya being able to produce few world class footballers. The purpose of this thesis was to provide easily accessib...

  13. Late Type 3b Endoleak with an Endurant Endograft

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    Mehmet Barburoglu

    2015-01-01

    Full Text Available Endovascular stent grafting with different commercially available stent graft systems is widely applied for the treatment of abdominal aortic aneurysms with high success rates in the current era. Various types of endoleaks are potential complications of the procedure. They usually occur in the early period. In this report, we present type 3b endoleak occurring 14 months after a successful endovascular abdominal aortic aneurysm repair with a Medtronic Endurant stent graft.

  14. Effect of ACTN3 gene on strength and endurance in soccer players.

    Science.gov (United States)

    Pimenta, Eduardo M; Coelho, Daniel B; Veneroso, Christiano E; Barros Coelho, Ering J; Cruz, Izinara R; Morandi, Rodrigo F; De A Pussieldi, Guilherme; Carvalho, Maria R S; Garcia, Emerson S; De Paz Fernández, José A

    2013-12-01

    Sports efficiency in activities in which strength and speed are the determining factors has been associated to the ACTN3 gene, which is responsible for the expression of α-actinin-3. Soccer is a mainly aerobic sport because of its long duration, but the acute actions that define the game demand a lot of strength and speed. The purpose of the present study was to compare the performance capacity of soccer players with different genotype groups of ACTN3 (XX, RX, and RR) in strength, speed, and endurance tests. Two hundred professional players of Brazilian soccer first division teams participated in this study. Speed, jump, and endurance test results were compared with the polymorphisms of the ACTN3 gene. It was noticed that RR individuals spent less time to run a 10-m path, compared with XX individuals (p soccer players of genotype ACTN3/RR are the fastest in short distances and present higher jump potential. ACTN3/XX individuals presented the highest aerobic capacity. These findings can be used in training load adjustment and can influence the development of tactical schemes in soccer matches.

  15. Enduring politics: the culture of obstacles in legislating for assisted reproduction technologies in Ireland

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    Jill Allison

    2016-12-01

    Full Text Available Assisted reproductive technology has become a normalized part of reproductive medicine in many countries around the world. Access, however, is uneven and inconsistent, facilitated and restricted by such factors as affordability, social and moral acceptance or refusal and local cultures of medical practice. In Ireland, assisted reproductive technology has been available since 1987 but remains unregulated by legislation. This creates an uncertain and untenable legal circumstance given the contested issues related to constitutional protection of the right to life of the unborn and the indeterminate legal status of embryos in vitro. This paper examines the impact of an enduring political impasse. It explores how clinical assisted reproductive technology services in Ireland operate both inside and outside dominant institutional frameworks, meeting a pronatalist and pro-family social and political agenda, while sometimes contradicting the pro-life politics that has continued to shape women’s reproductive lives. The medical approaches to infertility thus intersect with the ongoing debates around abortion, the failure of the government to regulate, and notions of embodied motherhood and responsibility within changing meanings of family and kinship. At the same time women and their partners seek assisted reproductive technology treatment in other countries throughout the European Union where laws differ and availability of services varies. A decade has passed since the Commission on Assisted Human Reproduction in Ireland released its recommendations; the enduring legislative vacuum leaves women, families and practitioners in potential legal limbo.

  16. INFLUENCE OF SHOCK VOLTAGE FROM THE ELECTRIC DISCHARGE ON THE FATIGUE ENDURANCE OF CARBON STEEL IN WATER

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    I. O. Vakulenko

    2015-09-01

    Full Text Available Purpose. The research supposes the explanation of influence of stress impulses from an electrical discharge in water on the level of the limited endurance at a cyclic loading of the thermally work-hardened carbon steel. Methodology. Material for research was steel 45 (0,45 % carbon with сoncentration of chemical elements within the limits of steel composition. Specimens for tests are made as plates in 1 thick, width 15 and length 120-180 mm. The structural state of steel corresponded to quenching on a martensite from the normal temperatures of annealing and tempering at 300C, duration of 1 h. Microstructure was investigated with the use of electronic microscopy, the density of dislocations was estimated on the methods of X-ray analysis. Hardness was measured on the method of Rockwell (scale of «C». A cyclic loading was carried out in the conditions of symmetric bend on a tester «Saturn-10» at a temperature +20C. The treatment by shock voltage from the electrical discharge was carried out in water on setting of bath type «Iskra-23», used for cleaning of castings manufactures. Electric impulses were formed at 15-18 kV with energy of 10-12 kJ and amplitude of 1-2 GPа. Findings. As a result of processing pulses of a pressure wave of heat-strengthened steel 45 found the increase of endurance under the cyclic loading corresponds to an increased amount of accumulated dislocations on the fracture surface. The use of Coffin–Manson Equation allowed finding the decrease of deformation per cycle of loading as a result of arising stress from an electrical discharge in water. On the fracture surface (after pulse exposure was found the increased number of dislocations, located in different crystallographic systems, that is a testament to the rather complicated development of dislocation transformations in the structure of steel, which provide an increase of endurance at a fatigue. The increase of the limited endurance became as a result of impulsive

  17. Venous hemogasometry of equines finalists in 90 km endurance races

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    Cinthia B.S. Dumont

    2014-06-01

    Full Text Available Front of exercise, the organic systems may suffer water-electrolyte and acid-base imbalances, particularly in the case of blood gases, demonstrating variations from different causes, whether respiratory and/or metabolic. Understanding the physiological adaptations to exercise is essential in the search for the optimum performance. In this way, this study measured the venous blood gases (pO2, pCO2, as well as the oxygen saturation (SatO2 in healthy equines, Arabian horses finalists in 90km endurance races. A total of fourteen Arabian horses were evaluated, nine males and five females, between six and 12 years old, finalists in 90km endurance races. There was a significant reduction in pO2, pCO2 and SatO2 after the exercise, however, the values remained within the normality range, and did not change the athletic performance of the animals, indicating a temporary alteration, assuming thus a character of physiological response to the exercise performed. The equines, finalists in 90 Km endurance races, demonstrated efficient ventilatory process, without any alterations in the athletic performance, being adapted to the type of exercise imposed.

  18. Muscular endurance training and motor unit firing patterns during fatigue.

    Science.gov (United States)

    Mettler, Joni A; Griffin, Lisa

    2016-01-01

    With muscular training, the central nervous system may regulate motor unit firing rates to sustain force output and delay fatigue. The aims of this study were to investigate motor unit firing rates and patterns of the adductor pollicis (AdP) muscle in young, able-bodied adults throughout a sustained submaximal isometric fatiguing contraction and postactivation potentiation pre-post 4 weeks of muscular endurance training. Fifteen participants (training group: N = 10; control group: N = 5) performed maximal voluntary contractions (MVCs) and a sustained isometric 20 % MVC fatigue task pre-post training. Single-motor-unit potentials were recorded from the AdP during the fatigue task with intramuscular fine-wire electrodes. Twitch force potentiation was measured during single-pulse electrical stimulation of the ulnar nerve before and after MVCs. The training group endurance trained their AdP muscle at 20 % MVC for 4 weeks. Mean motor unit firing rates were calculated every 5 % of endurance time (ET). ET increased by 45.2 ± 8.7 % (p pattern consisted of an initial slowing followed by an increase in firing rate late in fatigue and remained consistent pre-post training. Potentiation did not change following training. These data suggest that the ability of the neuromuscular system to sustain motor unit firing rate may serve as a mechanism to augment the duration of submaximal muscle performance and delay muscular fatigue.

  19. Serum cardiac troponin T after repeated endurance exercise events.

    Science.gov (United States)

    Bonetti, A; Tirelli, F; Albertini, R; Monica, C; Monica, M; Tredici, G

    1996-05-01

    Recently Dr. Rowe made a hypothesis according to which small areas of myocardial necrosis can be caused by microvascular spasm, related to high catecholamine concentrations and other mechanisms, following extraordinary unremitting endurance exercises or due to the cumulative effect of several endurance events. It was this last suggestion which prompted us to investigate 25 top cyclists, taking part in the 77th Giro d'Italia. Blood samples were obtained the day before the start of the competition and once a week thereafter until the end. We measured myoglobin, lactic dehydrogenase, total creatine kinase, creatine kinase isoenzyme MB and serum cardiac troponin T (Tn-T), a highly sensitive and specific method for the detection of myocardial injury. While at measuring time points which followed we found a significant increase in the serum indicators of muscle damage, compared with their values at the beginning of the race, creatine kinase isoenzyme MB did not rise significantly and cardiac Tn-T was found in the serum of only 5 athletes, repeatedly in some cases, but always below the cut off values considered as indicating myocardial ischemia. On the basis of the behaviour of creatine kinase isoenzyme MB and, above all, of cardiac Tn-T, we can conclude that heavy endurance exercises, repeated daily for 22 days, as was the case in our study, do not seem able to produce, in top athletes, permanent heart damage by means of acute myocardial injury.

  20. INFLUENCE OF PHYSICAL TRAINING ON CARDIORESPIRATORY ENDURANCE IN PREADOLESCENT AGE

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    Marjan Marinkovic

    2009-01-01

    Full Text Available Cardiorespiratory or aerobic endurance is the ability of the whole body to sustain physical activity for an extended period of time, involving relatively large groups of muscles. The attitudes on the possible impact of training on cardiorespiratory endurance in preadolescents are contradictory. Our study enrolled 195 boys aged 11 to 12 years. Experimental group (n=92 consisted of the children who had been involved with planned and programmed water polo training for at least two years. Control group (n=103 consisted of schoolchildren who only had had regular physical education in schools. Our investigation protocol included standardized anthropometric measurements and tests, performed respecting the appropriate protocols. Statistical analysis of the results demonstrated that there were no significant differences in age and relative values of oxygen consumption (VO2peak. Body height and mass, as well as the skinfold thickness, were significantly higher in experimental group subjects. The values of absolute VO2peak, FVC and FEV1.0 were also significantly higher in the examinees involved with water polo training. These findings stress the importance of a systematic training process even in this early period of growth and development in order for the trainees to acquire important functional advantages. We believe that a properly planned and programmed physical training can significantly contribute to the development of cardiorespiratory endurance even as early as preadolescent age.

  1. Motivational antecedent beliefs of endurance, strength, and flexibility activities.

    Science.gov (United States)

    Rhodes, Ryan E; Blanchard, Chris M; Matheson, Deborah Hunt

    2007-03-01

    Research into the correlates of physical activity has focused almost exclusively on physical activity as an omnibus construct. Health Canada and the American College of Sports Medicine, however, advocate physical activity in terms of performing regular endurance, strength, and flexibility activities. The purpose of this study was to investigate the absolute and relative contributions of behavioral, normative, and control beliefs associated with endurance, strength, and flexibility activities within a theory of planned behavior (TPB) structure. Participants were 185 undergraduates who completed measures of the TPB and a 2-week follow-up of endurance, strength, and flexibility behavior. Results using structural equation modeling and Hotelling's t-tests for dependent correlations identified different motivational antecedents for each type of physical activity (p behavior was influenced exclusively by behavioral beliefs, flexibility behavior was influenced by normative and control beliefs, and strength behavior was influenced by key behavioral, normative, and control beliefs. The different motivational profiles for each physical activity allude to the importance of tailoring interventions by physical activity type.

  2. Analysis of Tests Evaluating Sport Climbers’ Strength and Isometric Endurance

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    Ozimek Mariusz

    2016-12-01

    Full Text Available The present study was designed to determine which types of specific tests provide an effective evaluation of strength and endurance in highly trained competitive sport climbers. The research process consisted of three basic components: the measurement of selected somatic characteristics of the climbers, the assessment of their physical conditioning, and a search for correlations between the anthropometric and “conditioning” variables on the one hand, and climber’s performance on the other. The sample of subjects consisted of 14 experienced volunteer climbers capable of handling 7a- 8a+/b on-sight rock climbing grades. The strongest correlations (Spearman’s rank were found between climber’s competence and the relative results of the finger strength test (r = 0.7; much lower, but still statistically significant coefficients were found between the level of competence and the results of the muscle endurance tests (r = 0.53 – 0.57. Climbers aspiring to attain an elite level must have strong finger and forearm muscles, but most of all, they must be capable of releasing their potential during specific motor capability tests engaging these parts of the body. The forearm muscles of elite climbers must also be very resistant to fatigue. Since highly trained athletes vary only slightly in body mass, this variable does not have a major effect on their performance during strength and endurance tests.

  3. Cortical thickness and low insight into symptoms in enduring schizophrenia.

    Science.gov (United States)

    Emami, Seema; Guimond, Synthia; Mallar Chakravarty, M; Lepage, Martin

    2016-01-01

    Poor insight is a common, multidimensional phenomenon in patients with schizophrenia, associated with poorer outcomes and treatment non-adherence. Yet scant research has investigated the neuronal correlates of insight into symptoms (IS), a dimension of insight that may be particularly significant in enduring schizophrenia. Sixty-six patients with enduring schizophrenia (duration >4years) and 33 healthy controls completed MRI scanning and IQ, depression, and anxiety assessments. The Scale to Assess Insight-Expanded (SAI-E) measured insight into patients' four most prominent symptoms and patients were classified into two groups: low IS (0-2; n=33), and high IS (>2; n=33). We evaluated the association between cortical thickness (CT) and insight into symptoms using two methods: (1) a between-patients region-of-interest analysis in the insula, superior temporal gyrus (STG) and frontal lobe; and (2) a whole-brain exploratory regression between patient and controls. Brain regions were segmented using a neuroanatomical atlas and vertex-wise CT analyses were conducted with CIVET, covaried for age and sex. ROI analysis revealed thinner insula cortex in patients with low IS (pinsight-related differences in CT that has been previously unexplored in enduring schizophrenia.

  4. Structural protein alterations to resistance and endurance cycling exercise training.

    Science.gov (United States)

    Parcell, Allen C; Woolstenhulme, Mandy T; Sawyer, Robert D

    2009-03-01

    The muscle cytoskeleton is necessary for the effective transmission of forces generated by actin-myosin interactions. We have examined the impact of muscle force and exercise volume on the cytoskeleton by measuring desmin and dystrophin content in human skeletal muscle after 12 weeks of progressive resistance or endurance cycle training. Muscle biopsies of the vastus lateralis were obtained before and after training. Desmin and dystrophin content was determined using immunoblotting techniques. After resistance training, desmin content increased 82 +/- 18% (p < 0.05), whereas there was no change in desmin content with endurance cycling. Dystrophin content did not change in either group. One-repetition maximum and VO2max increased (p < 0.05) in the resistance and endurance groups, respectively. These data demonstrate that a high-tension stimulus impacts the cytoskeleton in contrast to high-volume concentric contractions. The tensile loading and eccentric components of resistance training are implicated in desmin alterations. Indeed, the functional improvements resulting from resistance training may be related in part to the mechanical integration provided by the desmin protein.

  5. Enduring symbols of dentistry: international metaphors of dental science.

    Science.gov (United States)

    Pearn, J

    2008-12-13

    Dentists' contributions to science and society extend beyond the practice of clinical dentistry and preventive oral health. Such service encompasses contributions to biology specifically and more generally to societal good works for which dentists are particularly esteemed. The profession of dentistry promotes the history and heritage of its craft and those who practise it. Enduring symbols of dentistry take many forms. These include metonymic emblems such as those of Cadmus and Saint Apollonia and the portrayal of effigies of twentieth century dentists on eponymous medals. Other enduring symbols are to be found in the names of streets and towns (eg Normanville in Australia) which commemorate dentists; and in the worldwide scientific names of plants and animal species which perpetuate singular contributions of dentists to biological science. Such include the scientific names of grasses (Deyeuxia rodwayi) after the Tasmanian dentist, Dr Leonard Rodway (1853-1936); seaweeds (Jeannerettia sp.) after a seaweed of the Pacific and Southern Oceans, after Dr Henry Jeannerett (1802-1886); gastropods (Typhina yatesi) after Dr Lorenzo Yates (1837-1909); copepods (eg Mimocalanus heronae) named to commemorate the life and works of Gayle Ann Heron (b.1923), a dental hygienist of the University of Washington, USA; and crabs (eg Cancer bellianus) named to commemorate the life and works of the leading British dentist of his day, Thomas Bell (1792-1880). This paper explores this theme of the creation and promotion of enduring symbols of dental science - enshrined in the civic, numismatic and taxonomic record.

  6. Arterial Elasticity, Strength, Fatigue, and Endurance in Older Women

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    Gary R. Hunter

    2014-01-01

    Full Text Available Arterial health may influence muscle function in older adults. Study purpose was to determine whether arterial elasticity is related to strength, central and peripheral fatigue, fatigue at rest, and treadmill endurance. Subjects were 91 healthy women aged >60. Treadmill endurance and maximal oxygen uptake (VO2 max were measured. Peripheral and central fatigue for the knee extensors were evaluated using two isometric fatigue tests (one voluntary and one adding electrical stimulation. Arterial elasticity was determined using radial artery pulse wave analysis. Linear multiple regression was used in statistical analysis. Large artery elasticity was associated with central fatigue (P<0.01 and treadmill endurance (P<0.02 after adjusting for VO2 max and knee extension strength. Subjective fatigue at rest was related to large artery elasticity after adjusting for ethnic origin (<0.02. Strength was significantly related to small artery elasticity after adjusting for ethnic origin, leg lean tissue, age, and blood pressure. Arterial elasticity is independently related to strength and fatigue in older women, especially in the central nervous system where arterial elasticity is independently related to perceptions of fatigue at rest and central fatigue. These results suggest that arterial health may be involved with the ability of the central nervous system to activate muscle in older women.

  7. Ultrasonic Fatigue Endurance of Thin Carbon Fiber Sheets

    Science.gov (United States)

    Domínguez Almaraz, Gonzalo M.; Ruiz Vilchez, Julio A.; Dominguez, Aymeric; Meyer, Yann

    2016-04-01

    Ultrasonic fatigue tests were carried out on thin carbon fiber sheets (0.3 mm of thickness) to determine the fatigue endurance under very high-frequency loading (20 kHz). This material, called the gas diffusion layer (GDL), plays a major role in the overall performances of proton exchange membrane fuel cells (PEMFCs). The study of its physical-chemical properties is an on-going subject in the literature; nevertheless, no knowledge is available concerning the high-frequency fatigue endurance. A principal difficulty in carrying out ultrasonic fatigue tests on this material was to determine the dimensions of testing specimen to fit the resonance condition. This aspect was solved by modal numerical simulation: The testing specimen has been a combination of a low-strength steel frame (to facilitate the attachment to the ultrasonic machine and to increase the mass of the specimen), and the carbon fiber hourglass-shape profile. Under resonance condition, a stationary elastic wave is generated along the specimen that induces high stress at the neck section and high displacements at the ends. Results show that fatigue life was close to 3 × 108 cycles when the high Von Misses stress at the neck section was 170 MPa, whereas fatigue life attains the 4.5 × 109 cycles when stress decreases to 117 MPa. Crack initiation and propagation were analyzed, and conclusions were drawn concerning the fatigue endurance of these fiber carbon sheets under ultrasonic fatigue testing.

  8. Enduring psychobiological effects of childhood adversity.

    Science.gov (United States)

    Ehlert, Ulrike

    2013-09-01

    This mini-review refers to recent findings on psychobiological long-term consequences of childhood trauma and adverse living conditions. The continuum of trauma-provoked aftermath reaches from healthy adaptation with high resilience, to severe maladjustment with co-occurring psychiatric and physical pathologies in children, adolescents and adults. There is increasing evidence of a strong interconnectivity between genetic dispositions, epigenetic processes, stress-related hormonal systems and immune parameters in all forms of (mal)-adjustment to adverse living conditions. Unfavorable constellations of these dispositions and systems, such as low cortisol levels and elevated markers of inflammation in maltreated children, seem to promote the (co)-occurrence of psychiatric and physical pathologies such as posttraumatic stress disorder, obesity, or diabetes. Although findings from prospective study designs support a deepened understanding of causal relations between adverse living conditions, including traumatic experiences, during childhood and its psychobiological effects, so far, little is known about the temporal coincidence of stress-sensitive developmental stages during childhood and adolescence and trauma consequences. Taken together, childhood adversity is a severe risk factor for the onset of psychobiological (mal)-adjustment, which has to be explained under consideration of diverse physiological systems and developmental stages of childhood and adolescence. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. [Enduring oral dryness after acne treatment].

    Science.gov (United States)

    Bots, C P; van Nieuw Amerongen, A; Brand, H S

    2003-07-01

    Medication influences the salivary flow rate frequently. In this paper a 26-year old patient is described, who used a systemic retinoid (a vitamin A derivate) when he was 18 years old. Since then, irreversible xerostomia was present. The oral complaints have been monitored during three years. Saliva was collected to assess the salivary flow rate and pH. The visco-elasticity of unstimulated whole saliva was high. This indicates a relatively low contribution of the gl. parotidea and a high mucin concentration in the collected saliva. Furthermore, parafilm only slightly stimulated the salivary flow rate. On the other hand, application of a 4% citric acid solution raised the flow rate to normal levels, without any delay. The medical history revealed no factors which could explain the the severe oral dryness and low salivary flow rate in rest. It was concluded that the low salivary flow rates and xerostomia might be related to the previous use of isotretinoin (Roaccutane). It is suggested to register and monitor the use of medication in patients with sudden oral health changes.

  10. Reinforcement of the Gas Barrier Properties of Polyethylene and Polyamide Through the Nanocomposite Approach: Key Factors and Limitations

    Directory of Open Access Journals (Sweden)

    Picard E.

    2015-02-01

    Full Text Available In this study, polyamide 6 (PA6 and polyethylene (PE nanocomposites were prepared from melt blending and a detailed characterization of the nanocomposite morphology and gas barrier properties was performed. The choice of the organoclay was adapted to each polymer matrix. Exfoliated morphology and improved gas transport properties were obtained by melt mixing the polar PA6 matrix and the organoclay, whereas a microcomposite with poor barrier properties was formed from the binary PE/organomodified clay mixture. Different modified polyethylenes were examined as compatibilizers for the polyethylene/organoclay system. The effect of compatibilizer molar mass, polarity and content was investigated on the clay dispersion and on the gas barrier properties. The optimal compatibilizer to clay weight ratio was found to be equal to 4 whatever the compatibilizer. However, a high degree of clay delamination was obtained with the high molar mass compatibilizer whereas highly swollen clay aggregates resulted from the incorporation of the low molar mass interfacial agents. Contrary to the PA based system, the barrier properties of PE nanocomposites were not directly related to the clay dispersion state but resulted also from the matrix/clay interfacial interactions. Oxidized wax was identified as a very promising interfacial agent and a step by step study was performed to optimize the gas transport properties of the systems based on PE, oxidized wax and organoclay. In particular, an interesting combination of oxidized wax and high molar mass maleic anhydride grafted polyethylene allowing dividing the gas permeability by a factor 2 in comparison with neat PE was proposed.

  11. Integrating Limiting-Factors Analysis with Process-Based Restoration to Improve Recovery of Endangered Salmonids in the Pacific Northwest, USA

    Directory of Open Access Journals (Sweden)

    Derek B. Booth

    2016-04-01

    Full Text Available Two approaches to ecological restoration planning, limiting-factors analysis and process-based restoration, are employed in efforts to recover endangered salmonid species throughout the Pacific Northwest of North America. Limiting-factors analysis seeks to identify physical limitations to fish production that may be addressed by habitat restoration; it is known as the “Field of Dreams” hypothesis (i.e., if you build it, they will come. Process-based restoration, in contrast, assumes that protection and/or restoration of watershed-scale processes will best achieve self-sustaining habitat features that support salmon populations. Two case studies from the Columbia River basin (northwestern USA display current efforts to integrate these two restoration approaches to improve salmonid populations. Although these examples both identify site-specific habitat features to construct, they also recognize the importance of supporting key watershed processes to achieve restoration goals. The challenge in advancing the practice of restoration planning is not in simply acknowledging the conceptual benefits of process-based restoration while maintaining a traditional focus on enumerating site-specific conditions and identifying habitat-construction projects, but rather in following process-based guidance during recovery planning and, ultimately, through implementation of on-the-ground actions. We encourage a realignment of the restoration community to truly embrace a process-based, multi-scalar view of the riverine landscape.

  12. COMPARISION OF DYNAMIC CYCLING VS STATIC CYCLING ON ENDURANCE, BALANCE, AND WALKING ABILITY OF CHILDREN WITH CEREBRAL PALSY

    Directory of Open Access Journals (Sweden)

    PatitapabanMohanty

    2015-08-01

    Full Text Available Background: The impairments in cerebral palsy can limit a child’s ability to play and exercise at intensities necessary to develop cardio respiratory fitness. Objective: To compare the effects of dynamic cycling, static cycling and conventional exercises in cardiovascular endurance, balance and walking ability in cerebral palsy children. Materials and Method: A total of 30 subjects were recruited in an experimental pre-post-test study design. Subjects were randomly assigned to 3 different treatment groups. The following outcome measures were measured: resting Heart Rate, 3 Minute Walk Test, GMFM-66, and Pediatric Balance Scale. All the three groups received conventional exercises. The experimental group 1 in addition received dynamic cycling protocol and experimental group 2 received static cycling protocol. The outcome was again evaluated at 6 weeks. Results: All the 3 groups showed significant pre to post improvement for the entire outcomes measured but GMFM-66. Results of the studied showed more significant improvement in both the cycling groups compared to the control group; Dynamic cycling group showing better response than static cycling group. Though all the groups showed improvement in GMFM-66, the dynamic cycling group showed better improvement followed by control group. Conclusion: Dynamic cycling incorporated with conventional exercises improves the cardiovascular endurance, balance and functional abilities than conventional exercises only. KEY WORDS: Cerebral Palsy, Dynamic Cycling, Static Cycling, Balance, Exercise, Walking, Endurance, Ability.

  13. Origin of mobility enhancement by chemical treatment of gate-dielectric surface in organic thin-film transistors: Quantitative analyses of various limiting factors in pentacene thin films

    Science.gov (United States)

    Matsubara, R.; Sakai, Y.; Nomura, T.; Sakai, M.; Kudo, K.; Majima, Y.; Knipp, D.; Nakamura, M.

    2015-11-01

    For the better performance of organic thin-film transistors (TFTs), gate-insulator surface treatments are often applied. However, the origin of mobility increase has not been well understood because mobility-limiting factors have not been compared quantitatively. In this work, we clarify the influence of gate-insulator surface treatments in pentacene thin-film transistors on the limiting factors of mobility, i.e., size of crystal-growth domain, crystallite size, HOMO-band-edge fluctuation, and carrier transport barrier at domain boundary. We quantitatively investigated these factors for pentacene TFTs with bare, hexamethyldisilazane-treated, and polyimide-coated SiO2 layers as gate dielectrics. By applying these surface treatments, size of crystal-growth domain increases but both crystallite size and HOMO-band-edge fluctuation remain unchanged. Analyzing the experimental results, we also show that the barrier height at the boundary between crystal-growth domains is not sensitive to the treatments. The results imply that the essential increase in mobility by these surface treatments is only due to the increase in size of crystal-growth domain or the decrease in the number of energy barriers at domain boundaries in the TFT channel.

  14. Democracy as a Limiting Factor for Politicised Cultural Populism in Malawi Demokratie und politisierter Kulturpopulismus in Malawi

    Directory of Open Access Journals (Sweden)

    Reuben Makayiko Chirambo

    2009-01-01

    Full Text Available Though Malawian democracy could still be described as in transition from authoritarianism, it has enabled an atmosphere for critical debate of and dissent against seemingly popular opinions, which was not possible during the authoritarian rule of former life president, Dr. H. K. Banda, 1964-1994. This article examines politicised cultural populism in Malawi under the dictatorship and democracy in comparative terms. President Banda, as a political populist, appropriated culture to legitimate and validate his political power as well as to cultivate popular support from the majority of ordinary people. Following reforms towards democracy since 1992, his successors have also tended towards populist politics by similarly appropriating culture and cultural activities, among other means, to cultivate popular support from mostly ordinary people for their regimes. Such politicised cultural populism involves adopting traditional roles, cultural symbols and images of power such as praise-titles, and participating in cultural activities such as traditional dances. This article examines the efforts of President Bingu wa Mutharika in the democratic dispensation to appropriate cultural artefacts used by Banda during a dictatorship in order to cultivate popular support for his regime. The article argues that Bingu’s efforts at politicised cultural populism are constrained, among other factors, by the nature and climate of democratic politics mainly because democracy, unlike a dictatorship, enables critical debate and the questioning of political leader’s behaviour and their motives. Auch wenn die Demokratie in Malawi sich immer noch in einem Übergangsstadium befindet, ist inzwischen eine Atmosphäre entstanden, in der eine kritische Debatte und das Äußern unpopulärer Meinungen möglich sind, was in den Jahren 1964-1994 unter dem früheren Präsidenten auf Lebenszeit, Dr. H. K. Banda, nicht denkbar war. Der Autor vergleicht die Nutzung von Elementen

  15. Critical factors in the limited occurrence of the Japanese tree sap mite Hericia sanukiensis (Acari: Astigmata: Algophagidae) inhabiting the sap of the oak Quercus acutissima.

    Science.gov (United States)

    Hayashi, Kyohei; Ichikawa, Toshihide; Yasui, Yukio

    2011-08-01

    Hericia sanukiensis (Astigmata: Algophagidae) is a semi-aquatic mite inhabiting fermented sap flux of the Japanese sawtooth oak (Quercus acutissima) and utilizes Nitidulidae (Coleoptera) as the dispersal (phoretic) carrier. Although nitidulid beetles are commonly found in sap flux, the occurrence of H. sanukiensis has been extremely limited to a few trees in Shikoku Island, Kagawa Prefecture, Japan. To elucidate the critical factors limiting the occurrence of this species, we compared several physical and biological characteristics of sap-exudation points, including the structure and temperature of tree trunks, period and abundance of sap exudation, and seasonal occurrence and dispersal behavior of nitidulid beetles between environments with and without mites. During the two consecutive years of field research, we found that only sap-exudation points with obvious tree holes (ringent area >10 cm², depth >10 cm) had sustained mite populations throughout the observation period. In contrast, for the sap-exudation points lacking tree holes, H. sanukiensis temporally (from spring to autumn) colonized only when the sap production was considerably high. Thus, we suggest that the settlement of H. sanukiensis populations requires tree holes as an overwintering habitat. Nitidulid beetles also concentrated in areas with high sap production and did not disperse from such habitats during the sap flow season. This indicates that H. sanukiensis mites may only disperse and colonize new habitats at very limited opportunities, such as drastic habitat deterioration, which may promote the movement of their carrier. Taken together, these findings may explain the limited occurrence of this mite species.

  16. Fatigue as a long-term risk factor for limitations in instrumental activities of daily living and/or mobility performance in older adults after 10 years

    Science.gov (United States)

    Mueller-Schotte, Sigrid; Bleijenberg, Nienke; van der Schouw, Yvonne T; Schuurmans, Marieke J

    2016-01-01

    Objectives Decline in the performance of instrumental activities of daily living (IADL) and mobility may be preceded by symptoms the patient experiences, such as fatigue. The aim of this study is to investigate whether self-reported non-task-specific fatigue is a long-term risk factor for IADL-limitations and/or mobility performance in older adults after 10 years. Methods A prospective study from two previously conducted cross-sectional studies with 10-year follow-up was conducted among 285 males and 249 females aged 40–79 years at baseline. Fatigue was measured by asking “Did you feel tired within the past 4 weeks?” (males) and “Do you feel tired?” (females). Self-reported IADLs were assessed at baseline and follow-up. Mobility was assessed by the 6-minute walk test. Gender-specific associations between fatigue and IADL-limitations and mobility were estimated by multivariable logistic and linear regression models. Results A total of 18.6% of males and 28.1% of females were fatigued. After adjustment, the odds ratio for fatigued versus non-fatigued males affected by IADL-limitations was 3.3 (P=0.023). In females, the association was weaker and not statistically significant, with odds ratio being 1.7 (P=0.154). Fatigued males walked 39.1 m shorter distance than those non-fatigued (P=0.048). For fatigued females, the distance was 17.5 m shorter compared to those non-fatigued (P=0.479). Conclusion Our data suggest that self-reported fatigue may be a long-term risk factor for IADL-limitations and mobility performance in middle-aged and elderly males but possibly not in females. PMID:27877027

  17. Acute hypoxia limits endurance but does not affect muscle contractile properties.

    NARCIS (Netherlands)

    Degens, H.; Sanchez Horneros, J.M.; Hopman, M.T.E.

    2006-01-01

    Acute hypoxia causes skeletal muscle dysfunction in vitro, but little is known about its effect on muscle function in vivo. In 10 healthy male subjects, isometric contractile properties and fatigue resistance of the quadriceps muscle were determined during normoxia and hypoxia using electrically evo

  18. Effect of Endurance, Strength and Combined Training on Lipid Profile, Insulin Resistance, and Serum Adiponectin Levels in Inactive Obese Children

    Directory of Open Access Journals (Sweden)

    AR Ramezani

    2016-10-01

    Full Text Available Background & aim: Nowadays, Iranian lifestyles are changing, especially children may be effected by the increase of cardiovascular diseases. Studies have shown that different methods of exercise are the most important determinants of cardiovascular risk factors. The aim of this study was to survey the lipid profile, insulin resistance, and adiponectin levels following eight weeks of endurance, strength and combined training in inactive obese children. Methods: The present quasi-experimental field was conducted on Sixty obese male children (age: 8-12 years, BMI between 30-35 kg/m2 according to the World Health Organization who were purposefully selected and randomly divided into four experimental groups of 15 individuals including endurance exercise, resistance exercise, combined exercise and control. Exercise training programs were performed four times a week for eight weeks. To assess variable changes, ANOVA with repeated measurement and one way ANOVA was used. Results: Results showed that after three types of exercise training  the BMI, total chlostrol, TG, LDL, VLDL, and insulin resistance significantly decreased in experimental groups compared to control group (P=0.001. Serum HDL and adiponectin was significantly increased after different training in experimental groups in comparison to control group (P=0.001.  Conclusion: According to the findings, it is suggested that among three types of exercise applied in this study, particularly, endurance training is use to prevent and reduce the incidence of cardiovascular diseases and obesity-related disorders in inactive obese children. .

  19. Long-Term High-Effort Endurance Exercise in Older Adults: Diminishing Returns for Cognitive and Brain Aging.

    Science.gov (United States)

    Young, Jeremy C; Dowell, Nicholas G; Watt, Peter W; Tabet, Naji; Rusted, Jennifer M

    2016-10-01

    While there is evidence that age-related changes in cognitive performance and brain structure can be offset by increased exercise, little is known about the impact long-term high-effort endurance exercise has on these functions. In a cross-sectional design with 12-month follow-up, we recruited older adults engaging in high-effort endurance exercise over at least 20 years, and compared their cognitive performance and brain structure with a nonsedentary control group similar in age, sex, education, IQ, and lifestyle factors. Our findings showed no differences on measures of speed of processing, executive function, incidental memory, episodic memory, working memory, or visual search for older adults participating in long-term high-effort endurance exercise, when compared without confounds to nonsedentary peers. On tasks that engaged significant attentional control, subtle differences emerged. On indices of brain structure, long-term exercisers displayed higher white matter axial diffusivity than their age-matched peers, but this did not correlate with indices of cognitive performance.

  20. Ultrasonic Fatigue Endurance of Aluminum Alloy AISI 6061-T6 on Pre-corroded and Non-corroded Specimens

    Science.gov (United States)

    Domínguez Almaraz, Gonzalo M.; Dueñas Aburto, Antonio; Correa Gómez, Erasmo

    2014-01-01

    Ultrasonic fatigue tests are carried out on aluminum alloy 6061-T6 in order to analyze the fatigue endurance behavior under artificial pre-corrosion attack by hydrochloric acid for the pH concentrations of 0.47 and 0.80. The pre-corrosion attack is used to simulate the long-time environmental effect and the corresponding decay of fatigue life in regard to non-corroded specimens. Experimental results show that ultrasonic fatigue endurance under these two degrees of pre-corrosion attack decreases dramatically. Furthermore, it is observed that crack initiation is frequently associated with one or several pre-corrosion pitting holes at the specimen surface. Pitting holes are assumed to be semi-hemispherical and the stress concentration factors are evaluated taking into account the size and proximity of two crack initiation pitting holes. The crack growth rates are obtained for the pre-corroded specimens and compared to the non-corroded specimen. Finally, conclusions are listed concerning ultrasonic fatigue endurance of testing specimens, together with the fracture surfaces, crack paths, and crack growth rates.

  1. The effects of postexercise consumption of a kefir beverage on performance and recovery during intensive endurance training.

    Science.gov (United States)

    O'Brien, K V; Stewart, L K; Forney, L A; Aryana, K J; Prinyawiwatkul, W; Boeneke, C A

    2015-11-01

    This study was designed to determine whether kefir accentuates the positive health benefits assessed by measures in fitness, body composition, or both, as a measure of cardiovascular disease risk as well as the biomarker C-reactive protein (CRP). Sixty-seven adult males and females aged 18 to 24 yr were assigned to 1 of 4 groups: (1) endurance training + control beverage, (2) endurance training +kefir beverage,(3) active control + control beverage, or (4) active control + kefir beverage. The exercise groups completed 15 wk of structured endurancetraining while the active control groups maintained their usual exercise routine. Additionally, each group was assigned to either a kefir or a calorie/macronutrient matched placebo beverage that was consumed twice per week. No significant interactions were found among groups with respect to outcome variables with the exception of serum CRP. The endurance training was effective in improving 1.5-mile (2.41 km) times and kefir supplementation may have been a factor in attenuating the increase in CRP that was observed over the course of the intervention period. This preliminary study suggests that kefir may be involved in improving the risk profile for cardiovascular disease as defined by CRP. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. A Systematic Review of Resistance Training Versus Endurance Training in COPD

    DEFF Research Database (Denmark)

    Iepsen, Ulrik Winning; Jørgensen, Karsten Juhl; Ringbaek, Thomas;

    2015-01-01

    controlled trials (328 participants). On the basis of moderate- to very low-quality evidence, we found no clinically important difference between RT and ET. We did not find sufficient data for a meta-analysis of total mortality, adverse events, dyspnea, or lean body mass. CONCLUSIONS:: We found......PURPOSE:: Endurance training (ET) as part of pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD) has been shown to improve exercise capacity and health-related quality of life, but dyspnea limits the exercise intensity. Therefore, resistance training (RT), which...... may cause less dyspnea, could be an alternative. The purpose of this review was to formulate evidence-based recommendations on the use of RT in pulmonary rehabilitation of patients with COPD. Our primary outcomes were health-related quality of life, activities of daily living, dyspnea, possible harm...

  3. [Therapeutic education in primary cardiovascular prevention. Interests and limits].

    Science.gov (United States)

    Baudet, M; Daugareil, C

    2014-09-01

    Lifestyle improvement is useful in the prevention of cardiovascular disease, but its practical implementation in the general population is limited. Patient therapeutic education can help go beyond these limits. In primary prevention, we propose a personalized program including one or several individual and collective sessions to help the participants towards a healthier lifestyle. This includes better education about six risk factors (tobacco, sedentary lifestyle, overweight, high blood pressure, high cholesterol, diabetes) as well as advice on better eating habits. The first recommendation is to limit processed meats, the other recommendations advise more fish, green vegetables, whole grains and beans, and fruits. Scores are attributed to six risk factors and five eating habits. These scores are given at the time of the first session and again a year later, thus permitting time comparisons. For the first 291 participants in the program, we observed at one year a significant improvement in physical activities of endurance and in the consumption of the recommended food groups (fish, green vegetables, fruits, whole grains and beans). The patient's lifestyle has improved as a whole, certain parameters more than others. Assessed patient therapeutic education should be offered to a larger number of people. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  4. ′Ha! What is the benefit of living next to the park?′ Factors limiting in-migration next to Tarangire National Park, Tanzania

    Directory of Open Access Journals (Sweden)

    Alicia Davis

    2011-01-01

    Full Text Available Controversies and contestations of park and other protected area policies, new conservation rules and regulations (formal and informal, and new land classifications are redefining land and resource use, and thus livelihood options, for four ethnically distinct communities around Tarangire National Park, Tanzania. Research was conducted on how livelihoods have been shaped by perceptions of and in response to conservation policies and community-based conservation projects. Several factors were revealed that provide examples of perceived problems and issues, which would deter in-migration to these communities bordering a national park. Migration into these areas, located to the east, north-west, and western border of Tarangire National Park may be limited, at best, due to issues of fear and mistrust, lack of access to and alienation from land and resources, ethnicity, and litigious actions. This paper addresses these limiting factors, revealing how real world examples of conservation issues can be used to inform policy, rather than relying solely on statistical-based modelling.

  5. The effects of elevated pain inhibition on endurance exercise performance

    Science.gov (United States)

    Waddington, Gordon; Keegan, Richard J.; Thompson, Kevin G.; Cathcart, Stuart

    2017-01-01

    Background The ergogenic effects of analgesic substances suggest that pain perception is an important regulator of work-rate during fatiguing exercise. Recent research has shown that endogenous inhibitory responses, which act to attenuate nociceptive input and reduce perceived pain, can be increased following transcranial direct current stimulation of the hand motor cortex. Using high-definition transcranial direct current stimulation (HD-tDCS; 2 mA, 20 min), the current study aimed to examine the effects of elevated pain inhibitory capacity on endurance exercise performance. It was hypothesised that HD-tDCS would enhance the efficiency of the endogenous pain inhibitory response and improve endurance exercise performance. Methods Twelve healthy males between 18 and 40 years of age (M = 24.42 ± 3.85) were recruited for participation. Endogenous pain inhibitory capacity and exercise performance were assessed before and after both active and sham (placebo) stimulation. The conditioned pain modulation protocol was used for the measurement of pain inhibition. Exercise performance assessment consisted of both maximal voluntary contraction (MVC) and submaximal muscular endurance performance trials using isometric contractions of the non-dominant leg extensors. Results Active HD-tDCS (pre-tDCS, −.32 ± 1.33 kg; post-tDCS, −1.23 ± 1.21 kg) significantly increased pain inhibitory responses relative to the effects of sham HD-tDCS (pre-tDCS, −.91 ± .92 kg; post-tDCS, −.26 ± .92 kg; p = .046). Irrespective of condition, peak MVC force and muscular endurance was reduced from pre- to post-stimulation. HD-tDCS did not significantly influence this reduction in maximal force (active: pre-tDCS, 264.89 ± 66.87 Nm; post-tDCS, 236.33 ± 66.51 Nm; sham: pre-tDCS, 249.25 ± 88.56 Nm; post-tDCS, 239.63 ± 67.53 Nm) or muscular endurance (active: pre-tDCS, 104.65 ± 42.36 s; post-tDCS, 93.07 ± 33.73 s; sham: pre-tDCS, 123.42 ± 72.48 s; post-tDCS, 100.27 ± 44

  6. The effects of elevated pain inhibition on endurance exercise performance

    Directory of Open Access Journals (Sweden)

    Andrew Flood

    2017-03-01

    Full Text Available Background The ergogenic effects of analgesic substances suggest that pain perception is an important regulator of work-rate during fatiguing exercise. Recent research has shown that endogenous inhibitory responses, which act to attenuate nociceptive input and reduce perceived pain, can be increased following transcranial direct current stimulation of the hand motor cortex. Using high-definition transcranial direct current stimulation (HD-tDCS; 2 mA, 20 min, the current study aimed to examine the effects of elevated pain inhibitory capacity on endurance exercise performance. It was hypothesised that HD-tDCS would enhance the efficiency of the endogenous pain inhibitory response and improve endurance exercise performance. Methods Twelve healthy males between 18 and 40 years of age (M = 24.42 ± 3.85 were recruited for participation. Endogenous pain inhibitory capacity and exercise performance were assessed before and after both active and sham (placebo stimulation. The conditioned pain modulation protocol was used for the measurement of pain inhibition. Exercise performance assessment consisted of both maximal voluntary contraction (MVC and submaximal muscular endurance performance trials using isometric contractions of the non-dominant leg extensors. Results Active HD-tDCS (pre-tDCS, −.32 ± 1.33 kg; post-tDCS, −1.23 ± 1.21 kg significantly increased pain inhibitory responses relative to the effects of sham HD-tDCS (pre-tDCS, −.91 ± .92 kg; post-tDCS, −.26 ± .92 kg; p = .046. Irrespective of condition, peak MVC force and muscular endurance was reduced from pre- to post-stimulation. HD-tDCS did not significantly influence this reduction in maximal force (active: pre-tDCS, 264.89 ± 66.87 Nm; post-tDCS, 236.33 ± 66.51 Nm; sham: pre-tDCS, 249.25 ± 88.56 Nm; post-tDCS, 239.63 ± 67.53 Nm or muscular endurance (active: pre-tDCS, 104.65 ± 42.36 s; post-tDCS, 93.07 ± 33.73 s; sham: pre-tDCS, 123.42 ± 72.48 s; post

  7. Physiological cardiac remodelling in response to endurance exercise training: cellular and molecular mechanisms.

    Science.gov (United States)

    Ellison, Georgina M; Waring, Cheryl D; Vicinanza, Carla; Torella, Daniele

    2012-01-01

    Exercise training fosters the health and performance of the cardiovascular system, and represents nowadays a powerful tool for cardiovascular therapy. Exercise exerts its beneficial effects through reducing cardiovascular risk factors, and directly affecting the cellular and molecular remodelling of the heart. Traditionally, moderate endurance exercise training has been viewed to determine a balanced and revertible physiological growth, through cardiomyocyte hypertrophy accompanied by appropriate neoangiogenesis (the Athlete's Heart). These cellular adaptations are due to the activation of signalling pathways and in particular, the IGF-1/IGF-1R/Akt axis appears to have a major role. Recently, it has been shown that physical exercise determines cardiac growth also through new cardiomyocyte formation. Accordingly, burgeoning evidence indicates that exercise training activates circulating, as well as resident tissue-specific cardiac, stem/progenitor cells. Dissecting the mechanisms for stem/progenitor cell activation with exercise will be instrumental to devise new effective therapies, encompassing myocardial regeneration for a large spectrum of cardiovascular diseases.

  8. Growth hormone enhances effects of endurance training on oxidative muscle metabolism in elderly women

    DEFF Research Database (Denmark)

    Lange, K H; Isaksson, F; Juul, A;

    2000-01-01

    The present study investigated whether recombinant human (rh) growth hormone (GH) combined with endurance training would have a larger effect on oxidative capacity, metabolism, and body fat than endurance training alone. Sixteen healthy, elderly women, aged 75 yr, performed closely monitored...... in the two subjects receiving rhGH. In conclusion, rhGH adds to the effects of endurance training on muscle oxidative enzymes and causes a reduction in body fat in elderly women....

  9. COMBINED STRENGTH AND ENDURANCE TRAINING IN COMPETITIVE SWIMMERS

    Directory of Open Access Journals (Sweden)

    Stian Aspenes

    2009-09-01

    Full Text Available A combined intervention of strength and endurance training is common practice in elite swimming training, but the scientific evidence is scarce. The influences between strength and endurance training have been investigated in other sports but the findings are scattered. Some state the interventions are negative to each other, some state there is no negative relationship and some find bisected and supplementary benefits from the combination when training is applied appropriately. The aim of this study was to investigate the impact of a combined intervention among competitive swimmers. 20 subjects assigned to a training intervention group (n = 11 or a control group (n = 9 from two different teams completed the study. Anthropometrical data, tethered swimming force, land strength, performance in 50m, 100m and 400m, work economy, peak oxygen uptake, stroke length and stroke rate were investigated in all subjects at pre- and post-test. A combined intervention of maximal strength and high aerobic intensity interval endurance training 2 sessions per week over 11 weeks in addition to regular training were used, while the control group continued regular practice with their respective teams. The intervention group improved land strength, tethered swimming force and 400m freestyle performance more than the control group. The improvement of the 400m was correlated with the improvement of tethered swimming force in the female part of the intervention group. No change occurred in stroke length, stroke rate, performance in 50m or 100m, swimming economy or peak oxygen uptake during swimming. Two weekly dry-land strength training sessions for 11 weeks increase tethered swimming force in competitive swimmers. This increment further improves middle distance swimming performance. 2 weekly sessions of high- intensity interval training does not improve peak oxygen uptake compared with other competitive swimmers

  10. Predicting intermittent running performance: critical velocity versus endurance index.

    Science.gov (United States)

    Buchheit, M; Laursen, P B; Millet, G P; Pactat, F; Ahmaidi, S

    2008-04-01

    The aim of the present study was to examine the ability of the critical velocity (CV) and the endurance index (EI) to assess endurance performance during intermittent exercise. Thirteen subjects performed two intermittent runs: 15-s runs intersected with 15 s of passive recovery (15/15) and 30-s runs with 30-s rest (30/30). Runs were performed until exhaustion at three intensities (100, 95 and 90 % of the speed reached at the end of the 30 - 15 intermittent fitness test, V (IFT)) to calculate i) CV from the slope of the linear relationship between the total covered distance and exhaustion time (ET) (iCV); ii) anaerobic distance capacity from the Y-intercept of the distance/duration relationship (iADC); and iii) EI from the relationship between the fraction of V (IFT) at which the runs were performed and the log-transformed ET (iEI). Anaerobic capacity was indirectly assessed by the final velocity achieved during the Maximal Anaerobic Running Test (VMART). ET was longer for 15/15 than for 30/30 runs at similar intensities. iCV (15/15) and iCV (30/30) were not influenced by changes in ET and were highly dependent on V (IFT). Neither iADC (15/15) nor iADC (30/30) were related to VMART. In contrast, iEI (15/15) was higher than iEI (30/30), and corresponded with the higher ET. In conclusion, only iEI estimated endurance capacity during repeated intermittent running.

  11. Endurance training and GH administration in elderly women

    DEFF Research Database (Denmark)

    Lange, K H; Lorentsen, J; Isaksson, F

    2001-01-01

    adipose tissue blood flow (ATBF; (133)Xe washout). Whole body fat oxidation was estimated simultaneously by indirect calorimetry. Before and after completion of the training program, measurements were performed both at rest and during 60 min of continuous cycling at a workload corresponding to 60...... and after completion of the training program. Similarly, no effect on subcutaneous abdominal adipose tissue lipolysis was observed when combining endurance training with rhGH administration. However, in both the placebo and the GH groups, fat oxidation was significantly increased during exercise performed...

  12. Supplementation strategies for gastrointestinal distress in endurance athletes

    Directory of Open Access Journals (Sweden)

    Vivian Ximeno Duarte

    2015-10-01

    Full Text Available The prevalence of gastrointestinal symptoms in the endurance athlete is about 25% to 70%. Even though it is recognized that the etiology of exercise-induced gastrointestinal distress is multifactorial, blood flow redistribution during physical activity and therefore gastrointestinal ischemia is often acknowledged as the main pathophysiology mechanism for the onset of symptoms. This review will provide an overview to the recent research on gastrointestinal function during strenuous exercise. In addition, we consider different nutritional interventions that could be evaluated for preventive or treatment interventions founding that ever though there is some research in the area, the scientific evidence does not support its use in athlete population.

  13. Effects of Endurance and Endurance-strength Exercise on Renal Function in Abdominally Obese Women with Renal Hyperfiltration:A Prospective Randomized Trial

    Institute of Scientific and Technical Information of China (English)

    Monika Szuliska; Damian Skrypnik; Marzena Ratajczak; Joanna Karolkiewicz; Edyta Mdry; Katarzyna Musialik; Jarosaw Walkowiak; Hieronim Jakubowski; Pawe Bogdaski

    2016-01-01

    ObjectiveObesity is associated with kidney defects.Physical activity is a key element in the treatment of obesity.The aim of this study was to compare the effect of endurance and endurance-strength training on kidney function in abdominally obese women. MethodsForty-four abdominally obese women were randomized to endurance training or endurance-strength training, three times a week for 3 months. Before and after the intervention, kidney function was assessed by measuring blood creatinine, urine creatinine, and urine albumin levels, and the albumin-to-creatinine ratio and glomerular filtration rate (GFR) were calculated. ResultsRenal hyperperfusion was present in both groups before the study. Following both types of physical activity, similar modifications of the investigated parameters were observed, but with no significant between-group differences.Both courses of training led to a significant increase in blood creatinine and a subsequent decrease in the GFR. A significant increase in urine creatinine and album levels, though not exceeding the range for microalbuminuria, was not accompanied by any difference in the albumin-to-creatinine ratio after endurance-strength training alone. ConclusionThree months of either endurance or endurance-strength training has a favorable and comparable effect on renal function in abdominally obese women with renal hyperfiltration.

  14. Tenax TA extraction to understand the rate-limiting factors in methyl-β-cyclodextrin-enhanced bioremediation of PAH-contaminated soil.

    Science.gov (United States)

    Sun, Mingming; Luo, Yongming; Teng, Ying; Christie, Peter; Jia, Zhongjun; Li, Zhengao

    2013-06-01

    The effectiveness of many bioremediation systems for PAH-contaminated soil may be constrained by low contaminant bioaccessibility due to limited aqueous solubility or large sorption capacity. Information on the extent to which PAHs can be readily biodegraded is of vital importance in the decision whether or not to remediate a contaminated soil. In the present study the rate-limiting factors in methyl-β-cyclodextrin (MCD)-enhanced bioremediation of PAH-contaminated soil were evaluated. MCD amendment at 10 % (w/w) combined with inoculation with the PAH-degrading bacterium Paracoccus sp. strain HPD-2 produced maximum removal of total PAHs of up to 35 %. The desorption of PAHs from contaminated soil was determined before and after 32 weeks of bioremediation. 10 % (w/w) MCD amendment (M2) increased the Tenax extraction of total PAHs from 12 to 30 % and promoted degradation by up to 26 % compared to 6 % in the control. However, the percentage of Tenax extraction for total PAHs was much larger than that of degradation. Thus, in the control and M2 treatment it is likely that during the initial phase the bioaccessibility of PAHs is high and biodegradation rates may be limited by microbial processes. On the other hand, when the soil was inoculated with the PAH-degrading bacterium (CKB and MB2), the slowly and very slowly desorbing fractions (F sl and F vl ) became larger and the rate constants of slow and very slow desorption (k sl and k vl ) became extremely small after bioremediation, suggesting that desorption is likely rate limiting during the second, slow phase of biotransformation. These results have practical implications for site risk assessment and cleanup strategies.

  15. Lake Roosevelt Fisheries Evaluation Program; Evaluation of Limiting Factors for Stocked Kokanee and Rainbow Trout in Lake Roosevelt, Washington, 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, Casey; Polacek, Matt

    2009-03-01

    Hatchery supplementation of kokanee Oncorhynchus nerka and rainbow trout O. mykiss has been the primary mitigation provided by Bonneville Power Administration for loss of anadromous fish to the waters above Grand Coulee Dam (GCD). The hatchery program for rainbow trout has consistently met management goals and provided a substantial contribution to the fishery; however, spawner returns and creel survey results for kokanee have been below management goals. Our objective was to identify factors that limit limnetic fish production in Lake Roosevelt by evaluating abiotic conditions, food limitations, piscivory, and entrainment. Dissolved oxygen concentration was adequate throughout most of the year; however, levels dropped to near 6 mg/L in late July. For kokanee, warm water temperatures during mid-late summer limited their nocturnal distribution to 80-100 m in the lower section of the reservoir. Kokanee spawner length was consistently several centimeters longer than in other Pacific Northwest systems, and the relative weights of rainbow trout and large kokanee were comparable to national averages. Large bodied daphnia (> 1.7 mm) were present in the zooplankton community during all seasons indicating that top down effects were not limiting secondary productivity. Walleye Stizostedion vitreum were the primary piscivore of salmonids in 1998 and 1999. Burbot Lota lota smallmouth bass Micropterus dolomieui, and northern pikeminnow Ptychocheilus oregonensis preyed on salmonids to a lesser degree. Age 3 and 4 walleye were responsible for the majority (65%) of the total walleye consumption of salmonids. Bioenergetics modeling indicated that reservoir wide consumption by walleye could account for a 31-39% loss of stocked kokanee but only 6-12% of rainbow trout. Size at release was the primary reason for differential mortality rates due to predation. Entrainment ranged from 2% to 16% of the monthly abundance estimates of limnetic fish, and could account for 30% of total

  16. Data Acquistion Controllers and Computers that can Endure, Operate and Survive Cryogenic Temperatures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Current and future NASA exploration flight missions require Avionics systems, Computers, Controllers and Data processing units that are capable of enduring extreme...

  17. Pars plana vitrectomy combined with internal limiting membrane peeling for recurrent macular edema due to branch retinal vein occlusion after antivascular endothelial growth factor treatments

    Directory of Open Access Journals (Sweden)

    Shirakata Y

    2016-02-01

    Full Text Available Yukari Shirakata,1 Kouki Fukuda,1 Tomoyoshi Fujita,1 Yuki Nakano,1 Hiroyuki Nomoto,2 Hidetaka Yamaji,3 Fumio Shiraga,4 Akitaka Tsujikawa1 1Department of Ophthalmology, Faculty of Medicine, Kagawa University, Miki-cho, 2Nomoto Eye Clinic, Himeji, 3Department of Ophthalmology, Shirai Eye Hospital, Mitoyo, 4Department of Ophthalmology, Okayama University, Okayama, Japan Purpose: To evaluate the anatomic and functional outcomes of pars plana vitrectomy combined with internal limiting membrane peeling for recurrent macular edema (ME due to branch retinal vein occlusion (BRVO after intravitreal injections of antivascular endothelial growth factor (anti-VEGF agents. Methods: Twenty-four eyes of 24 patients with treatment-naive ME from BRVO were treated with intravitreal injections of anti-VEGF agents. Recurred ME was treated with pars plana vitrectomy combined with internal limiting membrane peeling. Results: After the surgery, ME was significantly reduced at 1 month (P=0.031 and the reduction increased with time (P=0.007 at the final visit. With the reduction in ME, treated eyes showed a slow improvement in visual acuity (VA. At the final visit, improvement in VA was statistically significant compared with baseline (P=0.048. The initial presence of cystoid spaces, serous retinal detachment, or subretinal hemorrhage under the fovea, as well as retinal perfusion status, showed no association with VA improvement. However, the presence of epiretinal membrane showed a significant association with the visual recovery. Although eyes without epiretinal membrane showed visual improvement (-0.10±0.32 in logarithm of the minimum angle of resolution [logMAR], eyes with epiretinal membrane showed greater visual improvement (-0.38±0.12 in logMAR, P=0.012. Conclusion: For recurrent ME due to BRVO after anti-VEGF treatment, particularly when accompanied by epiretinal membrane, pars plana vitrectomy combined with internal limiting membrane peeling might be a

  18. Fatigue as a long-term risk factor for limitations in instrumental activities of daily living and/or mobility performance in older adults after 10 years

    Directory of Open Access Journals (Sweden)

    Mueller-Schotte S

    2016-11-01

    Full Text Available Sigrid Mueller-Schotte,1–3 Nienke Bleijenberg,1,2,4 Yvonne T van der Schouw,1 Marieke J Schuurmans2,4 1Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, the Netherlands; 2Department for the Chronically Ill, University of Applied Sciences Utrecht, the Netherlands; 3Department of Optometry and Orthoptics, University of Applied Sciences Utrecht, the Netherlands; 4Department of Rehabilitation, Nursing Science and Sports, University Medical Center Utrecht, the Netherlands Objectives: Decline in the performance of instrumental activities of daily living (IADL and mobility may be preceded by symptoms the patient experiences, such as fatigue. The aim of this study is to investigate whether self-reported non-task-specific fatigue is a long-term risk factor for IADL-limitations and/or mobility performance in older adults after 10 years. Methods: A prospective study from two previously conducted cross-sectional studies with 10-year follow-up was conducted among 285 males and 249 females aged 40–79 years at baseline. Fatigue was measured by asking “Did you feel tired within the past 4 weeks?” (males and “Do you feel tired?” (females. Self-reported IADLs were assessed at baseline and follow-up. Mobility was assessed by the 6-minute walk test. Gender-specific associations between fatigue and IADL-limitations and mobility were estimated by multivariable logistic and linear regression models. Results: A total of 18.6% of males and 28.1% of females were fatigued. After adjustment, the odds ratio for fatigued versus non-fatigued males affected by IADL-limitations was 3.3 (P=0.023. In females, the association was weaker and not statistically significant, with odds ratio being 1.7 (P=0.154. Fatigued males walked 39.1 m shorter distance than those non-fatigued (P=0.048. For fatigued females, the distance was 17.5 m shorter compared to those non-fatigued (P=0.479. Conclusion: Our data suggest that self-reported fatigue

  19. Endurance test for mini-plate fuel rig

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Heung June; Yang, Sun Kyu; Park, Jong Man; Kim, Chang Kyu; Ryu, Jeong Soo

    1999-07-01

    This report presents the pressure drop, vibration and endurance test results for mini-plate fuel rig which were designed by KAERI and fabricated by Daewoo Precision Co. From the pressure drop test results, it is noted that the flow velocity across the fuel rig corresponding to the pressure drop of 200 kPa is measured to be about 6.78 kg/sec. Vibration frequency for the fuel rig ranges from 14 to 19 Hz. RMZ (Root Mean Square) displacement for the fuel rig is less than 7 {mu}m, and the maximum displacement is less than 20 {mu}m. Based on the endurance rest results, the appreciable fretting wear for the fuel rig is not observed but the small amount of wear was observed at the interface region between the mini-plates and upper housing cap as well as at the slot regions of a bottom endplate interfacing with the bottom guide arms. (author). 4 refs., 10 tabs., 33 figs.

  20. Oxidative profiles of endurance horses racing different distances

    Directory of Open Access Journals (Sweden)

    R.F. Siqueira

    2014-04-01

    Full Text Available Increased oxidative stress during prolonged endurance exercises may result in muscle damage, fatigue and decreased performance. An adequate stress response during training is critical to obtain improved results and high animal welfare standards. The aim of this study was to evaluate the red blood cell haemolysate concentrations of superoxide dismutase (SOD, glutathione peroxidase (GPx, reduced glutathione (GSH and catalase (CAT and the plasma concentrations of malondialdehyde (MDA from endurance horses in different distances at high speed in a tropical climate. Fifteen horses were tested; five at 160km (18.54 - 17.16km/h race speed, five at 120km (21.53 - 17km/h race speed and five at 80km (20.06 - 18.01km/h race speed. Blood samples were collected at rest, immediately after and three hours after the horses left the final vet check and three, seven and fourteen days after the race. No significant increases (P > 0.05 in the levels of SOD, GPx, GSH, CAT or MDA were observed for any of the times or distances examined. Based on these observations, we conclude that reactive oxygen species (ROS formation during exercise evokes specific adaptations, such as increased antioxidant/oxidative damage-repairing enzyme activity, increased resistance to oxidative stress and lower levels of oxidative damage.

  1. Emotions and trait emotional intelligence among ultra-endurance runners.

    Science.gov (United States)

    Lane, Andrew M; Wilson, Mathew

    2011-07-01

    The aim of this study was to investigate relationships between trait emotional intelligence and emotional state changes over the course of an ultra-endurance foot race covering a route of approximately 175 miles (282 km) and held in set stages over six days. A repeated measures field design that sought to maintain ecological validity was used. Trait emotional intelligence was defined as a relatively stable concept that should predict adaptive emotional states experienced over the duration of the race and therefore associate with pleasant emotions during a 6-stage endurance event. Thirty-four runners completed a self-report measure of trait emotional intelligence before the event started. Participants reported emotional states before and after each of the six races. Repeated measures ANOVA results showed significant variations in emotions over time and a main effect for trait emotional intelligence. Runners high in self-report trait emotional intelligence also reported higher pleasant and lower unpleasant emotions than runners low in trait emotional intelligence. Findings lend support to the notion that trait emotional intelligence associates with adaptive psychological states, suggesting that it may be a key individual difference that explains why some athletes respond to repeated bouts of hard exercise better than others. Future research should test the effectiveness of interventions designed to enhance trait emotional intelligence and examine the attendant impact on emotional responses to intense exercise during multi-stage events. Copyright © 2011. Published by Elsevier Ltd.

  2. Cerebral autoregulation dynamics in endurance-trained individuals

    DEFF Research Database (Denmark)

    Lind-Holst, Mikkel; Cotter, James D; Helge, Jørn W;

    2011-01-01

    of increase in the cerebrovascular conductance index (CVCi = MCA V(mean)/MAP) appeared later in the athletes (3.9 ± 0.4 vs. 2.7 ± 0.4s, P = 0.01). Spectral analysis revealed a normal MAP-to-MCA V(mean) phase in both groups but ~40% higher normalized MAP to MCA V(mean) low-frequency transfer function gain...... in untrained subjects and was associated with parallel changes in indexes of cerebral blood flow. Once initiated, the autoregulatory response was similar between the groups. A delayed onset of autoregulation with a larger normalized transfer gain conforms with a less effective dampening of MAP oscillations...... pressure (MAP) after 2.5 min of leg ischemia in endurance athletes and untrained subjects (maximal O(2) uptake: 69 ± 7 vs. 42 ± 5 ml O(2)·min(-1)·kg(-1); n = 9 for both, means ± SE). After cuff release when seated, endurance athletes had larger drops in MAP (94 ± 6 to 62 ± 5 mmHg, -39%, vs. 99 ± 5 to 73...

  3. Fertilization for High Yields in Corn-Sweet Potato-Wheat Rotation: A Systematic Approach to Nutrient Limiting Factors of Soils in Chongqing, China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A systematic approach was adopted to investigate the nutrient limiting factors in gray-brown purple soils and yellow soils derived from limestone in Chongqing, China, to study balanced fertilization for corn, sweet potato and wheat in rotation. The results showed that N, P and K were deficient in both soils, Cu, Mn, S andZn in the gray-brown purple soils and Ca, Mg, Mo and Zn for the yellow soils. Balanced fertilizer application increased yields of corn, sweet potato and wheat by 28.4%, 28.7% and 4.4%, respectively, as compared to the local farmers' practice. The systematic approach can be considered as one of the most efficient and reliable methods in fertility study.

  4. Energetics of endurance exercise in young horses determined by nuclear magnetic resonance metabolomics

    Directory of Open Access Journals (Sweden)

    Margaux Marie-Hélène, Olivia Luck

    2015-07-01

    Full Text Available Long-term endurance exercise severely affects metabolism in both human and animal athletes resulting in serious risk of metabolic disorders during or after competition. Young horses (up to 6 years old can compete in races up to 90 km despite limited scientific knowledge of energetic metabolism responses to long distance exercise in these animals. The hypothesis of this study was that there would be a strong effect of endurance exercise on the metabolomic profiles of young horses and that the energetic metabolism response in young horses would be different from that of more experienced horses. Metabolomic profiling is a powerful method that combines Nuclear magnetic resonance (NMR spectrometry with supervised orthogonal projection on latent structure (OPLS statistical analysis. 1H-NMR spectra were obtained from plasma samples drawn from young horses (before and after competition. The spectra obtained before and after the race from the same horse (92 samples were compared using OPLS. The statistical parameters showed the robustness of the model (R2Y=0.947, Q2Y=0.856 and CV-ANOVA p-value < 0.001. For confirmation of the predictive value of the model, a test set of 104 sample spectra were projected by the model, which provided perfect predictions as the area under the receiving-operator curve was 1. The metabolomic profile determined with the OPLS model showed that glycemia after the race was lower than glycemia before the race, despite the involvement of lipid and protein catabolism. An OPLS model was calculated to compare spectra obtained on plasma taken after the race from 6-year-old horses and from experienced horses (cross-validated ANOVA p-value < 0.001. The comparison of metabolomic profiles in young horses to those from experienced horses showed that experienced horses maintained their glycemia with higher levels of lactate and a decrease of plasma lipids after the race.

  5. L-Arginine but not L-glutamine likely increases exogenous carbohydrate oxidation during endurance exercise.

    Science.gov (United States)

    Rowlands, David S; Clarke, Jim; Green, Jackson G; Shi, Xiaocai

    2012-07-01

    The addition of L-arginine or L-glutamine to glucose-electrolyte solutions can increase intestinal water, glucose, and sodium absorption in rats and humans. We evaluated the utility of L-arginine and L-glutamine in energy-rehydration beverages through assessment of exogenous glucose oxidation and perceptions of exertion and gastrointestinal distress during endurance exercise. Eight cyclists rode 150 min at 50% of peak power on four occasions while ingesting solutions at a rate of 150 mL 15 min(-1) that contained (13)C-enriched glucose (266 mmol L(-1)) and sodium citrate ([Na(+)] 60 mmol L(-1)), and either: 4.25 mmol L(-1) L-arginine or 45 mmol L(-1) L-glutamine, and as controls glucose only or no glucose. Relative to glucose only, L-arginine invoked a likely 12% increase in exogenous glucose oxidation (90% confidence limits: ± 8%); however, the effect of L-glutamine was possibly trivial (4.5 ± 7.3%). L-Arginine also led to very likely small reductions in endogenous fat oxidation rate relative to glucose (12 ± 4%) and L-glutamine (14 ± 4%), and relative to no glucose, likely reductions in exercise oxygen consumption (2.6 ± 1.5%) and plasma lactate concentration (0.20 ± 0.16 mmol L(-1)). Effects on endogenous and total carbohydrate oxidation were inconsequential. Compared with glucose only, L-arginine and L-glutamine caused likely small-moderate effect size increases in perceptions of stomach fullness, abdominal cramp, exertion, and muscle tiredness during exercise. Addition of L-arginine to a glucose and electrolyte solution increases the oxidation of exogenous glucose and decreases the oxygen cost of exercise, although the mechanisms responsible and impact on endurance performance require further investigation. However, L-arginine also increases subjective feelings of gastrointestinal distress, which may attenuate its other benefits.

  6. Energetics of endurance exercise in young horses determined by nuclear magnetic resonance metabolomics

    Science.gov (United States)

    Luck, Margaux M.; Le Moyec, Laurence; Barrey, Eric; Triba, Mohamed N.; Bouchemal, Nadia; Savarin, Philippe; Robert, Céline

    2015-01-01

    Long-term endurance exercise severely affects metabolism in both human and animal athletes resulting in serious risk of metabolic disorders during or after competition. Young horses (up to 6 years old) can compete in races up to 90 km despite limited scientific knowledge of energetic metabolism responses to long distance exercise in these animals. The hypothesis of this study was that there would be a strong effect of endurance exercise on the metabolomic profiles of young horses and that the energetic metabolism response in young horses would be different from that of more experienced horses. Metabolomic profiling is a powerful method that combines Nuclear Magnetic Resonance (NMR) spectrometry with supervised Orthogonal Projection on Latent Structure (OPLS) statistical analysis. 1H-NMR spectra were obtained from plasma samples drawn from young horses (before and after competition). The spectra obtained before and after the race from the same horse (92 samples) were compared using OPLS. The statistical parameters showed the robustness of the model (R2Y = 0.947, Q2Y = 0.856 and cros-validated ANOVA p predictive value of the model, a test set of 104 sample spectra were projected by the model, which provided perfect predictions as the area under the receiving-operator curve was 1. The metabolomic profile determined with the OPLS model showed that glycemia after the race was lower than glycemia before the race, despite the involvement of lipid and protein catabolism. An OPLS model was calculated to compare spectra obtained on plasma taken after the race from 6-year-old horses and from experienced horses (cross-validated ANOVA p horses to those from experienced horses showed that experienced horses maintained their glycemia with higher levels of lactate and a decrease of plasma lipids after the race. PMID:26347654

  7. Urine concentrations of oral salbutamol in samples collected after intense exercise in endurance athletes.

    Science.gov (United States)

    Hostrup, Morten; Kalsen, Anders; Auchenberg, Michael; Rzeppa, Sebastian; Hemmersbach, Peter; Bangsbo, Jens; Backer, Vibeke

    2014-06-01

    Our objective was to investigate urine concentrations of 8 mg oral salbutamol in samples collected after intense exercise in endurance athletes. Nine male endurance athletes with a VO2max of 70.2 ± 5.9 mL/min/kg (mean ± SD) took part in the study. Two hours after administration of 8 mg oral salbutamol, subjects performed submaximal exercise for 15 min followed by two, 2-min exercise bouts at an intensity corresponding to 110% of VO2max and a bout to exhaustion at same intensity. Urine samples were collected 4, 8, and 12 h following administration of salbutamol. Samples were analyzed by the Norwegian World Anti-doping Agency (WADA) laboratory. Adjustment of urine concentrations of salbutamol to a urine specific gravity (USG) of 1.020 g/mL was compared with no adjustment according to WADA's technical documents. We observed greater (P = 0.01) urine concentrations of salbutamol 4 h after administration when samples were adjusted to a USG of 1.020 g/mL compared with no adjustment (3089 ± 911 vs. 1918 ± 1081 ng/mL). With the current urine decision limit of 1200 ng/mL for salbutamol on WADA's 2013 list of prohibited substances, fewer false negative urine samples were observed when adjusted to a USG of 1.020 g/mL compared with no adjustment. In conclusion, adjustment of urine samples to a USG of 1.020 g/mL decreases risk of false negative doping tests after administration of oral salbutamol. Adjusting urine samples for USG might be useful when evaluating urine concentrations of salbutamol in doping cases.

  8. No Evidence of a Common DNA Variant Profile Specific to World Class Endurance Athletes

    Science.gov (United States)

    Wolfarth, Bernd; Wang, Guan; Sarzynski, Mark A.; Alexeev, Dmitry G.; Ahmetov, Ildus I.; Boulay, Marcel R.; Cieszczyk, Pawel; Eynon, Nir; Filipenko, Maxim L.; Garton, Fleur C.; Generozov, Edward V.; Govorun, Vadim M.; Houweling, Peter J.; Kawahara, Takashi; Kostryukova, Elena S.; Kulemin, Nickolay A.; Larin, Andrey K.; Maciejewska-Karłowska, Agnieszka; Miyachi, Motohiko; Muniesa, Carlos A.; Murakami, Haruka; Ospanova, Elena A.; Padmanabhan, Sandosh; Pavlenko, Alexander V.; Pyankova, Olga N.; Santiago, Catalina; Sawczuk, Marek; Scott, Robert A.; Uyba, Vladimir V.; Yvert, Thomas; Perusse, Louis; Ghosh, Sujoy; Rauramaa, Rainer; North, Kathryn N.; Lucia, Alejandro; Pitsiladis, Yannis; Bouchard, Claude

    2016-01-01

    There are strong genetic components to cardiorespiratory fitness and its response to exercise training. It would be useful to understand the differences in the genomic profile of highly trained endurance athletes of world class caliber and sedentary controls. An international consortium (GAMES) was established in order to compare elite endurance athletes and ethnicity-matched controls in a case-control study design. Genome-wide association studies were undertaken on two cohorts of elite endurance athletes and controls (GENATHLETE and Japanese endurance runners), from which a panel of 45 promising markers was identified. These markers were tested for replication in seven additional cohorts of endurance athletes and controls: from Australia, Ethiopia, Japan, Kenya, Poland, Russia and Spain. The study is based on a total of 1520 endurance athletes (835 who took part in endurance events in World Championships and/or Olympic Games) and 2760 controls. We hypothesized that world-class athletes are likely to be characterized by an even higher concentration of endurance performance alleles and we performed separate analyses on this subsample. The meta-analysis of all available studies revealed one statistically significant marker (rs558129 at GALNTL6 locus, p = 0.0002), even after correcting for multiple testing. As shown by the low heterogeneity index (I2 = 0), all eight cohorts showed the same direction of association with rs558129, even though p-values varied across the individual studies. In summary, this study did not identify a panel of genomic variants common to these elite endurance athlete groups. Since GAMES was underpowered to identify alleles with small effect sizes, some of the suggestive leads identified should be explored in expanded comparisons of world-class endurance athletes and sedentary controls and in tightly controlled exercise training studies. Such studies have the potential to illuminate the biology not only of world class endurance performance but

  9. Evaluation of limiting factors affecting photovoltaic performance of low-temperature-processed TiO₂ films in dye-sensitized solar cells.

    Science.gov (United States)

    Lee, Taek-Yong; Kim, Hui-Seon; Park, Nam-Gyu

    2014-04-14

    Limiting factors affecting photovoltaic performance of dye-sensitized solar cell employing low-temperature-processed TiO2 films were investigated. TiO2 films were prepared at a low temperature of 200 °C using the normal alcohol-containing binder-free TiO2 paste (LT200). Their photovoltaic performance was compared to a high-temperature (550 °C) annealed TiO2 film prepared using a polymer binder containing TiO2 paste (HT550). Compared to the proportional increase in conversion efficiency with TiO2 film thickness upto 14 μm for HT550, the increase in efficiency was terminated at relatively smaller thickness of about 8 μm for LT200 mainly due to unaugmented photocurrent. From the transient photocurrent-voltage studies, the electron transport rate was found to be almost identical, while charge recombination was one order of magnitude faster for LT200. Consequently, the electron diffusion length was more than 2-3 times shorter for LT200 than for HT550. Electron diffusion length and electron life time obtained from electrochemical impedance analysis were well consistent with those observed from transient measurement. Density of states (DOS) was evaluated to be shallow and narrow in LT200, which was responsible for limiting photovoltaic performance in the low-temperature processed TiO2 film.

  10. Granulocyte colony-stimulating factor mobilized CFU-F can be found in the peripheral blood but have limited expansion potential.

    Science.gov (United States)

    Lund, Troy C; Tolar, Jakub; Orchard, Paul J

    2008-06-01

    Bone marrow mesenchymal stem cells are multipotent cells found lining the bone marrow cavity supporting the growth and differentiation of hematologic progenitors. There is growing evidence that these cells can, under the right circumstances, enter the peripheral circulation. We show that granulocyte colony-stimulating factor mobilized peripheral blood contains cells which form colonies and have a similar fibroblastic morphology (termed CFU-F) to bone marrow mesenchymal stem cells. These cells were found at a very low incidence (0.0002%). Mobilized peripheral blood CFU-F were successfully differentiated into osteogenic and adipogenic lineages. FACS analysis showed that the cells had a similar profile to bone marrow mesenchymal stem cells. Importantly, mobilized peripheral blood CFU-F had limited expansion potential and became senescent 20-25 days after isolation. Mobilized peripheral blood CFU-F also did not have any telomerase activity and displayed significant telomere shortening. The rarity of CFU-F in mobilized peripheral blood and the subsequent pressure to divide in cell culture probably contribute to early cellular senescence. Their potential for use in transplant or gene therapy is, therefore, limited.

  11. Multiple-geographic-scale genetic structure of two mangrove tree species: the roles of mating system, hybridization, limited dispersal and extrinsic factors.

    Directory of Open Access Journals (Sweden)

    Gustavo M Mori

    Full Text Available Mangrove plants comprise a unique group of organisms that grow within the intertidal zones of tropical and subtropical regions and whose distributions are influenced by both biotic and abiotic factors. To understand how these extrinsic and intrinsic processes influence a more fundamental level of the biological hierarchy of mangroves, we studied the genetic diversity of two Neotropical mangrove trees, Avicenniagerminans and A. schaueriana, using microsatellites markers. As reported for other sea-dispersed species, there was a strong differentiation between A. germinans and A. schaueriana populations sampled north and south of the northeastern extremity of South America, likely due to the influence of marine superficial currents. Moreover, we observed fine-scale genetic structures even when no obvious physical barriers were present, indicating pollen and propagule dispersal limitation, which could be explained by isolation-by-distance coupled with mating system differences. We report the first evidence of ongoing hybridization between Avicennia species and that these hybrids are fertile, although this interspecific crossing has not contributed to an increase in the genetic diversity the populations where A. germinans and A. schaueriana hybridize. These findings highlight the complex interplay between intrinsic and extrinsic factors that shape the distribution of the genetic diversity in these sea-dispersed colonizer species.

  12. Gene expression in skeletal muscle of coronary artery disease patients after concentric and eccentric endurance training.

    Science.gov (United States)

    Zoll, J; Steiner, R; Meyer, K; Vogt, M; Hoppeler, H; Flück, M

    2006-03-01

    Low-intensity concentric (CET) and eccentric (EET) endurance-type training induce specific structural adaptations in skeletal muscle. We evaluated to which extent steady-state adaptations in transcript levels are involved in the compensatory alterations of muscle mitochondria and myofibrils with CET versus EET at a matched metabolic exercise intensity of medicated, stable coronary patients (CAD). Biopsies were obtained from vastus lateralis muscle before and after 8 weeks of CET (n=6) or EET (n=6). Transcript levels for factors involved in mitochondrial biogenesis (PGC-1alpha, Tfam), mitochondrial function (COX-1, COX-4), control of contractile phenotype (MyHC I, IIa, IIx) as well as mechanical stress marker (IGF-I) were quantified using an reverse-transcriptase polymerase chain reaction approach. After 8 weeks of EET, a reduction of the COX-4 mRNA level by 41% and a tendency for a drop in Tfam transcript concentration (-33%, P=0.06) was noted. This down-regulation corresponded to a drop in total mitochondrial volume density. MyHC-IIa transcript levels were specifically decreased after EET, and MyHC-I mRNA showed a trend towards a reduction (P=0.08). Total fiber cross-sectional area was not altered. After CET and EET, the IGF-I mRNA level was significantly increased. The PGC-1alpha significantly correlated with Tfam, and both PGC-1alpha and Tfam significantly correlated with COX-1 and COX-4 mRNAs. Post-hoc analysis identified significant interactions between the concurrent medication and muscular transcript levels as well as fiber size. Our findings support the concept that specific transcriptional adaptations mediate the divergent mitochondrial response of muscle cells to endurance training under different load condition and indicate a mismatch of processes related to muscle hypertrophy in medicated CAD patients.

  13. Relationship between Core Stability Muscle Endurance and Static and Dynamic Balance in Basketball Players

    Directory of Open Access Journals (Sweden)

    farzaneh saki

    2016-03-01

    Full Text Available Objective: Balancing is the most basic function of the neuromuscular system in performing all simple and complex activities that contribute to health-related physical fitness. Core stability may be a contributing factor to static and dynamic balance. The aim of this study was to investigate the relationship between core stability muscle endurance and static and dynamic balance in basketball players. Methods: 100 basketball players (50 female and 50 male players were selected randomly based on the including criteria.To evaluate core stability muscle strength, a set of tests from core stability exercises was used. Static and dynamic balance were evaluated by Bass Stick and Y balance test respectively. Normality of the data was evaluated using the Kolmogorov Smirnoff test. Data analysis was performed by Spearman product moment coefficient test and independent samples t test. Significant level of p&le0/05 was used in all statistical analyses. Results: Results of t-test showed no significant difference between static balance in boys and girls, while significant differences were observed between dynamic balance and core stability in males and females. In other words, core stability and dynamic balance in boys were more than girls. Also, the results of correlation analysis showed a significant relationship between core stability and dynamic balance (p=0.00 However, no significant relationship was observed between core stability and static balance (p=0.451. Conclusion: Due to the correlation between muscle endurance and dynamic balance in the present study, it can be implied that core stability exercises can improve balance.

  14. Factors influencing use of long-acting versus short-acting contraceptive methods among reproductive-age women in a resource-limited setting.

    Science.gov (United States)

    Tibaijuka, Leevan; Odongo, Robert; Welikhe, Emma; Mukisa, Wilber; Kugonza, Lilian; Busingye, Imelda; Nabukalu, Phelomena; Ngonzi, Joseph; Asiimwe, Stephen B; Bajunirwe, Francis

    2017-04-04

    Unplanned pregnancy remains a common problem in many resource-limited settings, mostly due to limited access to modern family planning (FP) services. In particular, use of the more effective long-acting reversible contraceptive (LARC) methods (i.e., intrauterine devices and hormonal implants) remains low compared to the short-acting methods (i.e., condoms, hormonal pills, injectable hormones, and spermicides). Among reproductive-age women attending FP and antenatal care clinics in Uganda, we assessed perceptions and practices regarding the use of modern contraceptive methods. We specifically aimed to evaluate factors influencing method selection. We performed a mixed-methods cross-sectional study, in which we administered structured interviews to 180 clients, and conducted 4 focus group discussions (FGDs) with 36 clients and 8 in-depth personal qualitative interviews with health service providers. We summarized quantitative data and performed latent content analysis on transcripts from the FGDs and qualitative interviews. The prevalence of ever use for LARC methods was 23%. Method characteristics (e.g., client control) appeared to drive method selection more often than structural factors (such as method availability) or individual client characteristics (such as knowledge and perceptions). The most common reasons for choosing LARC methods were: longer protection; better child-spacing; and effectiveness. The most common reasons for not choosing LARC methods included requiring a client-controlled method and desiring to conceive in the near future. The most common reasons for choosing short-acting methods were ease of access; lower cost; privacy; perceived fewer side effects; and freedom to stop using a method without involving the health provider. The personal characteristics of clients, which appeared to be important were client knowledge and number of children. The structural factor which appeared to be important was method availability. Our results suggest that

  15. Comparison between two types of anaerobic speed endurance training in competitive soccer players

    DEFF Research Database (Denmark)

    Mohr, Magni; Krustrup, Peter

    2016-01-01

    speed endurance production (SEP) or speed endurance maintenance (SEM) training (two additional sessions/wk for 4 weeks) during the competitive season. Players performed the Yo-Yo intermittent recovery level 2 test (YYIR2) and a repeated sprint test (RST) pre- and postintervention. Yo-Yo IR2 performance...

  16. 77 FR 25536 - Surety Companies Acceptable On Federal Bonds: Endurance American Insurance Company

    Science.gov (United States)

    2012-04-30

    ... Supplement No. 17 to the Treasury Department Circular 570, 2011 Revision, published July 1, 2011, at 76 FR... Fiscal Service Surety Companies Acceptable On Federal Bonds: Endurance American Insurance Company AGENCY.... 9305 to the following company: Endurance American Insurance Company (NAIC 10641). Business Address:...

  17. Analysis of the Static Strength and Relative Endurance of Women Athletes

    Science.gov (United States)

    Heyward, Vivian; McCreary, Leslie

    1977-01-01

    Investigations of static strength and relative endurance of the grip muscles of women athletes revealed that mean endurance time was significantly greater than for men. Results were discussed in light of evidence suggesting possible sex differences in muscle hypertrophy, capillarization of muscle tissue, critical occluding tension level, and…

  18. Effects of Dining on Tongue Endurance and Swallowing-Related Outcomes

    Science.gov (United States)

    Kays, Stephanie A.; Hind, Jacqueline A.; Gangnon, Ronald E.; Robbins, JoAnne

    2010-01-01

    Purpose: The purpose of this study was to test the hypothesis that eating a meal reduces tongue strength and endurance in healthy old and young adults. It was predicted that older adults would show greater declines in tongue endurance while demonstrating higher perceived effort, longer meal durations, and clinical signs of swallowing difficulty.…

  19. Endurance training enhances skeletal muscle interleukin-15 in human male subjects

    DEFF Research Database (Denmark)

    Rinnov, Anders; Yfanti, Christina; Nielsen, Søren

    2014-01-01

    endurance running. With the present study we aimed to determine if muscular IL-15 production would increase in human male subjects following 12 weeks of endurance training. In two different studies we obtained plasma and muscle biopsies from young healthy subjects performing: (1) 12 weeks of ergometer...

  20. The Relationship between Selected Body Composition Variables and Muscular Endurance in Women

    Science.gov (United States)

    Esco, Michael R.; Olson, Michele S.; Williford, Henry N.

    2010-01-01

    The primary purpose of this study was to determine if muscular endurance is affected by referenced waist circumference groupings, independent of body mass and subcutaneous abdominal fat, in women. This study also explored whether selected body composition measures were associated with muscular endurance. Eighty-four women were measured for height,…