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Sample records for rowing ergometer tests

  1. Analysis of anaerobic capacity in rowers using Wingate test on cycle and rowing ergometer.

    PubMed

    Klasnja, Aleksandar; Barak, Otto; Popadić-Gaćesa, Jelena; Drapsin, Miodrag; Knezević, Aleksandar; Grujić, Nikola

    2010-01-01

    The 30-s all-out Wingate test has been used in athletes of all sport specialties to measure the capacity for short duration, high power output while cycling. The aim of this study was to establish differences in measuring anaerobic capacity between the classic Wingate test on a cycling ergometer and the modified Wingate test on a rowing ergometer in rowers. A group of20 rowers was tested by both the cycle and rowing ergometers during 30s of maximum power to test anaerobic capacity and to make correlation between these tests. The parameters measured were the peak power and mean power. The peak power on the cycling ergometer was 475 +/- 75.1W and 522.4 +/- 81W (p < 0.05) on the rowing ergometer. The mean power on the cycling ergometer and the rowing ergometer was 344.4 +/- 51.1W and 473.7W +/- 67.2, (p < 0.05) respectively. The maximum values were achieved at the same time on both ergometers, but remained on the higher level till the end of the test on the rowing ergometer. By correlating the anaerobic parameters of the classic Wingate test and a modified Wingate test on the rowing ergometer a significant positive correlation was detected in the peak power (r = 0.63, p < 0.05) as well as in the mean power (r = 0.65, p < 0.05). The results show that the rowers achieved better results of the anaerobic parameters on the rowing ergometer compared to the cycling ergometer due to a better mechanical efficiency. It is concluded that the modified Wingate test on the rowing ergometer can be used in rowers for testing their anaerobic capacity as a sport specific test ergometer since it provides more precise results.

  2. Peak Power Output Test on a Rowing Ergometer: A Methodological Study.

    PubMed

    Metikos, Boris; Mikulic, Pavle; Sarabon, Nejc; Markovic, Goran

    2015-10-01

    We aimed to examine the reliability and validity of the peak power output test on a rowing ergometer (Concept II Model D Inc.) and to establish the "optimal resistance" at which this peak power output was observed in 87 participants with varying levels of physical activity and rowing expertise: 15 male and 12 female physically inactive students (age: 21 ± 2 years), 16 male and 20 female physically active students (age: 23 ± 2 years), and 15 male and 9 female trained rowers (age: 19 ± 2 years). The participants performed countermovement jump (CMJ) test on a force plate, followed by 3 maximal-effort rowing trials using the lowest, medium, and the highest adjustable resistance settings (i.e., "1", "5," and "10" on the resistance control dial on the ergometer) in randomized order. The test proved to be reliable (coefficients of variation: 2.6-6.5%; intraclass correlation coefficients: 0.87-0.98). The correlation coefficients between CMJ peak power and rowing peak power (both in watts per kilogram) were fairly consistent across all 3 groups of participants and resistance levels, ranging between r = 0.70 and r = 0.78. Finally, the highest power output was observed at the highest resistance setting in 2 nonathletic groups (p < 0.01), whereas rowers seem to produce the highest power output at the moderate-resistance setting. We conclude that the power output test on a Concept II rowing ergometer may serve as a reliable and valid tool for assessing whole-body peak power output in untrained individuals and rowing athletes.

  3. Fluctuating asymmetry as a predictor for rowing ergometer performance.

    PubMed

    Longman, D; Stock, J T; Wells, J C K

    2011-08-01

    Fluctuating asymmetry (FA) can be defined as an organism's deviation from perfect bilateral symmetry. FA has been of interest to evolutionary biologists as it may be indicative of the ability of an individual to express its genotype in a stable manner. Asymmetry has been shown to correlate with success in both intra- and inter-sexual selection in various species, including humans. A growing body of knowledge is emerging concerning the relationship between asymmetry and sporting ability. This study seeks to expand upon understanding of developmental stability and athletics by investigating the association between asymmetry and performance in rowers. Both male and female competitors from a range of abilities were tested (76 males and 70 females), with asymmetry being determined through bilateral digit measurements and performance through personal best time over 2000 m on the Concept 2 indoor rowing ergometer. Significant negative correlations were observed between asymmetry and 2000 m ergometer performance in both males and females. The relationship remained significant after adjustment for rowing experience and height. These results suggest that asymmetry may serve as a predictor of potential ability in the sport of rowing. The cause for the association between asymmetry and sporting performance has yet to be identified. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Effect of BMI on knee joint torques in ergometer rowing.

    PubMed

    Roemer, Karen; Hortobagyi, Tibor; Richter, Chris; Munoz-Maldonado, Yolanda; Hamilton, Stephanie

    2013-12-01

    Although an authoritative panel recommended the use of ergometer rowing as a non-weight-bearing form of exercise for obese adults, the biomechanical characterization of ergometer rowing is strikingly absent. We examined the interaction between body mass index (BMI) relative to the lower extremity biomechanics during rowing in 10 normal weight (BMI 18-25), 10 overweight (BMI 25-30 kg·m⁻²), and 10 obese (BMI > 30 kg·m⁻²) participants. The results showed that BMI affects joint kinematics and primarily knee joint kinetics. The data revealed that high BMI leads to unfavorable knee joint torques, implying increased loads of the medial compartment in the knee joint that could be avoided by allowing more variable foot positioning on future designs of rowing ergometers.

  5. Sports biomechanics in the research of the Department of Biomechanics of University School of Physical Education in Poznań. Part 1. Biomechanics of rowing: tests on rowing ergometers, reconstruction and synthesis.

    PubMed

    Dworak, Lechosław B

    2010-01-01

    The purpose of this study is to reconstruct the early phase of scientific research conducted at the Department of Biomechanics of the University School of Physical Education in Poznan, particularly the work on biomechanics of rowing, conducted as part of the Ministerial Project PR 105, entitled "The effectiveness of training and competition as well as regeneration in sports". Three kinds of research have been described, carried out with the use of the rowing ergometers. The first was the research on neuromuscular coordination in the rowing cycle, the second was the research on kinematic and dynamic characteristics of rowing on the Universal Rowing Ergometer UEW - 1, while the last one concerned determination of maximum forces generated by functional muscle groups in two characteristic rowing positions within the closed biochain of the torso and the limbs.

  6. Effects of oral supplementation with plant superoxide dismutase extract on selected redox parameters and an inflammatory marker in a 2,000-m rowing-ergometer test.

    PubMed

    Skarpanska-Stejnborn, Anna; Pilaczynska-Szczesniak, Lucja; Basta, Piotr; Deskur-Smielecka, Ewa; Woitas-Slubowska, Donata; Adach, Zdzislaw

    2011-04-01

    The aim of this study was to investigate the effect of plant superoxide dismutase extract (GliSODin) supplementation on the balance of oxidants and antioxidants in the serum and erythrocytes of competitive rowers. The double-blinded study included 19 members of the Polish rowing team who were participating in a preparatory camp. Subjects were randomly assigned to the supplemented group (n = 10), who received 2 capsules (500 mg) of GliSODin extract once daily for 6 weeks, or the placebo group (n = 9). At the beginning and end of the study, subjects performed a 2,000-m maximum-effort test on a rowing ergometer. Blood samples were taken from the antecubital vein before each exercise test, 1 min after completing the test, and after a 24-hr restitution period. The following redox parameters were assessed in erythrocytes: superoxide dismutase (SOD) activity, glutathione peroxidase activity, and concentrations of thiobarbituric-acid-reactive substances. In addition, creatine kinase activity and total antioxidant capacity were measured in plasma samples, lactate levels were determined in capillary blood samples, and C-reactive protein and lactate dehydrogenase concentrations were measured in serum. After supplementation, SOD activity was significantly higher (p = .0037) in the supplemented group than the placebo group, and C-reactive protein was significantly (p = .00001) lower in athletes receiving GliSODin than those in the placebo group. In conclusion, supplementation with an extract rich in SOD activity promoted antioxidant status and protected against increased inflammation in the serum of professional rowers but had no effect on oxidative damage induced by exhaustive exercise.

  7. Cardio-respiratory and electromyographic responses to ergometer and on-water rowing in elite rowers.

    PubMed

    Bazzucchi, I; Sbriccoli, P; Nicolò, A; Passerini, A; Quinzi, F; Felici, F; Sacchetti, M

    2013-05-01

    The aim of this study was to compare muscle activation and cardio-respiratory response during ergometer and on-water rowing. Nine internationally competitive rowers (five Olympic Games medal winners, age 25.6 ± 4.8 years) were requested to perform a 1,000 m race simulation test in the two conditions. Surface electromyographic (sEMG) signals from trapezius superior (TRS), latissimus dorsi (LD), biceps brachii (BB), rectus femoris (RF), vastus medialis (VAM), vastus lateralis (VAL), biceps femoris (BF) and tibialis anterior (TA) muscles were recorded continuously during the tests together with other cardio-respiratory parameters: heart rate (HR), ventilation (VE), oxygen consumption (VO₂). On-water, subjects covered the same distance in a longer time (218.4 ± 3.8 s vs. 178.1 ± 5.6 s during ergometer test). TRS, LD, BB, RF, VAM and VAL muscle activation on-water was lower than off-water during the rowing race. VO₂ and VE responses were similar between the two conditions even if the time to complete the 1,000 m race simulation test was higher on-water. The results indicate that for most of the analyzed muscles EMG activation on the ergometer is higher than on-water with the maximal activity at the beginning of the on-water test due reasonably to overcome the forces opposing the forward motion, while the ergometer task elicited increasing muscle activation over time. The present data may be considered by coaches when choosing a rowing ergometer in substitution for the training on-water or when relying on the indoor tests to select the crew.

  8. Comparison of Rowing on a Concept 2 Stationary and Dynamic Ergometer

    PubMed Central

    Benson, Aaron; Abendroth, Julianne; King, Deborah; Swensen, Thomas

    2011-01-01

    Biomechanical and physiological responses to rowing 1000 m at a power output equivalent to a 2000 m race were compared in 34 collegiate rowers (17 women, 17 men) rowing on a stationary and dynamic Concept 2 ergometer. Stroke ratio, peak handle force, rate of force development, impulse, and respiratory exchange ratio decreased by 15.7, 14.8, 10.9, 10.2 and 1.9%, respectively, on the dynamic ergometer. In contrast, percent time to peak force and stroke rate increased by 10.5 and 12.6%, respectively, during dynamic ergometry; the changes in stroke rate and impulse were greater for men than women. Last, VO2 was 5.1% higher and efficiency 5. 3% lower on the dynamic ergometer for men. Collegiate rowers used higher stoke rates and lower peak stroke forces to achieve a similar power output while rowing at race pace on the dynamic ergometer, which may have increased the cardiopulmonary demand and possibly reduced force production in the primary movers. Differences were more pronounced in males than females; this dichotomy may be more due to dynamic ergometer familiarity than sex. Key points When rowing at a constant power output, all rowers used higher stroke rates and lower stroke forces on the Concept 2 Dynamic ergometer as compared to the Concept 2 Stationary ergometer. When rowing at a constant power output, cardiopulmonary demand was higher for all rowers, as measured by heart rate, on the Concept 2 Dynamic ergometer as compared to the Concept 2 Stationary ergometer. When rowing at a constant power output, efficiency was lower for male rowers on the Concept 2 Dynamic ergometer as compared to the Concept 2 Stationary ergometer. PMID:24149871

  9. Muscle Synergies of Untrained Subjects during 6 min Maximal Rowing on Slides and Fixed Ergometer.

    PubMed

    Shaharudin, Shazlin; Zanotto, Damiano; Agrawal, Sunil

    2014-12-01

    The slides ergometer (SE) was an improvisation from fixed ergometer (FE) to bridge the gap of mechanics between ergometer rowing and on-water rowing. The specific mechanical constraints of these two types of ergometers may affect the pattern of muscle recruitment, coordination and adaptation. The main purpose of this study was to evaluate the muscle synergy during 6 minutes maximal rowing on slides (SE) and fixed ergometers (FE). The laterality of muscle synergy was also examined. Surface electromyography activity, power output, heart rate, stroke length and stroke rate were analyzed from nine physically active subjects to assess the rowing performance. Physically active subjects, who were not specifically trained in rowing, were chosen to exclude the training effect on muscle synergy. Principal component analysis (PCA) with varimax rotation was applied to extract muscle synergy. Three muscle synergies were sufficient to explain the majority of variance in SE (94.4 ± 2.2 %) and FE (92.8 ± 1.7 %). Subjects covered more rowing distance, exerted greater power output and attained higher maximal heart rate during rowing on SE than on FE. The results proved the flexibility of muscle synergy to adapt to the mechanical constraints. Rowing on SE emphasized on bi-articular muscles contrary to rowing on FE which relied on cumulative effect of trunk and upper limb muscles during propulsive phase. Key pointsThree muscle synergies were extracted during maximal rowing on both fixed and slides ergometerUntrained subjects emphasized leg muscles while rowing on SEUntrained subjects focused on back muscles during FE rowing.

  10. Higher rate of fat oxidation during rowing compared with cycling ergometer exercise across a range of exercise intensities.

    PubMed

    Egan, B; Ashley, D T; Kennedy, E; O'Connor, P L; O'Gorman, D J

    2016-06-01

    The relative contribution of carbohydrate and fat oxidation to energy expenditure during exercise is dependent on variables including exercise intensity, mode, and recruited muscle mass. This study investigated patterns of substrate utilization during two non-weightbearing exercise modalities, namely cycling and rowing. Thirteen young, moderately trained males performed a continuous incremental (3-min stages) exercise test to exhaustion on separate occasions on an electronically braked cycle (CYC) ergometer and an air-braked rowing (ROW) ergometer, respectively. On two further occasions, participants performed a 20-min steady-state exercise bout at ∼50%VO2peak on the respective modalities. Despite similar oxygen consumption, rates of fat oxidation (FATox ) were ∼45% higher during ROW compared with CYC (P < 0.05) across a range of power output increments. The crossover point for substrate utilization occurred at a higher relative exercise intensity for ROW than CYC (57.8 ± 2.1 vs 42.1 ± 3.6%VO2peak , P < 0.05). During steady-state submaximal exercise, the higher FATox during ROW compared with CYC was maintained (P < 0.05), but absolute FATox were 42% (CYC) and 28% (ROW) lower than during incremental exercise. FATox is higher during ROW compared with CYC exercise across a range of exercise intensities matched for energy expenditure, and is likely as a consequence of larger muscle mass recruited during ROW.

  11. Caution: the use of an electromagnetic device to measure trunk kinematics on rowing ergometers.

    PubMed

    Ng, Leo; Burnett, Angus; Campbell, Amity; O'Sullivan, Peter

    2009-09-01

    The aim of the study was to determine the accuracy and variability of an electromagnetic device in measuring spinal kinematics on a traditional and replica rowing ergometer. Kinematic data collected from the 3-Space Fastrak system using a Standard Concept II ergometer were compared with a replica ergometer that was in part, composed of non-ferrous materials (modified ergometer). The Fastrak's sensors were fixed to a wooden "spine" with known angles (as measured by an inclinometer). The mean inclinometer angle from four sensors (1 +/- 0.20) was significantly different than the mean angle recorded on the standard ergometer (-5.4 +/- 3.40) (p = 0.007) whilst the angles recorded on the modified ergometer (1.4 +/- 0.80) were statistically equivalent to the inclinometer recordings (p = 0.660). These results indicate that the presence of ferrous material in a standard ergometer reduced the accuracy and increased the variability of data collected with the electromagnetic device. However, information collected on largely non-ferrous ergometers can provide coaches, biomechanists and clinicians with a quick and effective way to measure trunk kinematics during ergometer rowing.

  12. Does a bout of strength training affect 2,000 m rowing ergometer performance and rowing-specific maximal power 24 h later?

    PubMed

    Gee, Thomas I; French, Duncan N; Howatson, Glyn; Payton, Stephen J; Berger, Nicolas J; Thompson, Kevin G

    2011-11-01

    Rowers regularly undertake rowing training within 24 h of performing bouts of strength training; however, the effect of this practice has not been investigated. This study evaluated the impact of a bout of high-intensity strength training on 2,000 m rowing ergometer performance and rowing-specific maximal power. Eight highly trained male club rowers performed baseline measures of five separate, static squat jumps (SSJ) and countermovement jumps (CMJ), maximal rowing ergometer power strokes (PS) and a single 2,000 m rowing ergometer test (2,000 m). Subsequently, participants performed a high-intensity strength training session consisting of various multi-joint barbell exercises. The 2,000 m test was repeated at 24 and 48 h post-ST, in addition SSJ, CMJ and PS tests were performed at these time points and also at 2 h post-ST. Muscle soreness, serum creatine kinase (CK) and lactate dehydrogenase (LDH) were assessed pre-ST and 2, 24 and 48 h post-ST. Following the ST, there were significant elevations in muscle soreness (2 and 24 h, P < 0.01), CK (2, 24 and 48 h, P < 0.01), and LDH (2 h, P < 0.05) in comparison to baseline values. There were significant decrements across all time points for SSJ, CMJ and PS, which ranged between 3 and 10% (P < 0.05). However, 2,000 m performance and related measurements of heart rate and blood lactate were not significantly affected by ST. In summary, a bout of high-intensity strength training resulted in symptoms of muscle damage and decrements in rowing-specific maximal power, but this did not affect 2,000 m rowing ergometer performance in highly trained rowers.

  13. Pink Noise in Rowing Ergometer Performance and the Role of Skill Level.

    PubMed

    Den Hartigh, Ruud J; Cox, Ralf F; Gernigon, Christophe; Van Yperen, Nico W; Van Geert, Paul L

    2015-03-27

    The aim of this study was to examine (1) the temporal structures of variation in rowers' (natural) ergometer strokes in order to make inferences about the underlying motor organization, and (2) the relation between these temporal structures and skill level. Four high-skilled and five lower-skilled rowers completed 550 strokes on a rowing ergometer. Detrended Fluctuation Analysis was used to quantify the temporal structure of the intervals between force peaks. Results showed that the temporal structure differed from random, and revealed prominent patterns of pink noise for each rower. Furthermore, the high-skilled rowers demonstrated more pink noise than the lower-skilled rowers. The presence of pink noise suggests that rowing performance emerges from the coordination among interacting component processes across multiple time scales. The difference in noise pattern between high-skilled and lower-skilled athletes indicates that the complexity of athletes' motor organization is a potential key characteristic of elite performance.

  14. Pink Noise in Rowing Ergometer Performance and the Role of Skill Level.

    PubMed

    Den Hartigh, Ruud J R; Cox, Ralf F A; Gernigon, Christophe; Van Yperen, Nico W; Van Geert, Paul L C

    2015-10-01

    The aim of this study was to examine (1) the temporal structures of variation in rowers’ (natural) ergometer strokes to make inferences about the underlying motor organization, and (2) the relation between these temporal structures and skill level. Four high-skilled and five lower-skilled rowers completed 550 strokes on a rowing ergometer. Detrended Fluctuation Analysis was used to quantify the temporal structure of the intervals between force peaks. Results showed that the temporal structure differed from random, and revealed prominent patterns of pink noise for each rower. Furthermore, the high-skilled rowers demonstrated more pink noise than the lower-skilled rowers. The presence of pink noise suggeststhat rowing performance emerges from the coordination among interacting component processes across multiple time scales. The difference in noise pattern between high-skilled and lower-skilled athletes indicates that the complexity of athletes’ motor organization is a potential key characteristic of elite performance.

  15. The effect of including a series of isometric conditioning contractions to the rowing warm-up on 1,000-m rowing ergometer time trial performance.

    PubMed

    Feros, Simon A; Young, Warren B; Rice, Anthony J; Talpey, Scott W

    2012-12-01

    Rowing requires strength, power, and strength-endurance for optimal performance. A rowing-based warm-up could be enhanced by exploiting the postactivation potentiation (PAP) phenomenon, acutely enhancing power output at the beginning of a race where it is needed most. Minimal research has investigated the effects of PAP on events of longer duration (i.e. 1,000-m rowing). The purpose of this research was to investigate the effects of PAP on 1,000-m rowing ergometer performance through the use of 2 different warm-up procedures: (a) a rowing warm-up combined with a series of isometric conditioning contractions, known as the potentiated warm-up (PW), and (b) a rowing warm-up only (NW). The isometric conditioning contractions in the PW were performed by "pulling" an immovable handle on the rowing ergometer, consisting of 5 sets of 5 seconds (2 seconds at submaximal intensity, and 3 seconds at maximal intensity), with a 15-second recovery between sets. The 1,000-m rowing ergometer time trial was performed after each warm-up condition, whereby mean power output, mean stroke rate, and split time were assessed every 100 m. Ten Australian national level rowers served as the subjects and performed both conditions in a counterbalanced order on separate days. The PW reduced 1,000-m time by 0.8% (p > 0.05). The PW improved mean power output by 6.6% (p < 0.01) and mean stroke rate by 5.2% (p < 0.01) over the first 500 m; resulting in a reduction of 500-m time by 1.9% (p < 0.01), compared with the NW. It appears that the inclusion of isometric conditioning contractions to the rowing warm-up enhance short-term rowing ergometer performance (especially at the start of a race) to a greater extent than a rowing warm-up alone.

  16. Relative shank to thigh length is associated with different mechanisms of power production during elite male ergometer rowing.

    PubMed

    Greene, Andrew J; Sinclair, Peter J; Dickson, Michael H; Colloud, Floren; Smith, Richard M

    2009-11-01

    The effect of anthropometric differences in shank to thigh length ratio upon timing and magnitude of joint power production during the drive phase of the rowing stroke was investigated in 14 elite male rowers. Rowers were tested on the RowPerfect ergometer which was instrumented at the handle and foot stretcher to measure force generation, and a nine segment inverse dynamics model used to calculate the rower's joint and overall power production. Rowers were divided into two groups according to relative shank thigh ratio. Time to half lumbar power generation was significantly earlier in shorter shank rowers (p = 0.028) compared to longer shank rowers, who showed no lumbar power generation during the same period of the drive phase. Rowers with a relatively shorter shank demonstrated earlier lumbar power generation during the drive phase resulting from restricted rotation of the pelvic segment requiring increased lumbar extension in these rowers. Earlier lumbar power generation and extension did not appear to directly affect performance measures of the short shank group, and so can be attributed to a technical adaptation developed to maximise rowing performance.

  17. Critical velocity: a predictor of 2000-m rowing ergometer performance in NCAA D1 female collegiate rowers.

    PubMed

    Kendall, Kristina L; Smith, Abbie E; Fukuda, David H; Dwyer, Teddi R; Stout, Jeffrey R

    2011-06-01

    The aims of this study were to examine the use of the critical velocity test as a means of predicting 2000-m rowing ergometer performance in female collegiate rowers, and to study the relationship of selected physiological variables on performance times. Thirty-five female collegiate rowers (mean ± s: age 19.3 ± 1.3 years; height 1.70 ± 0.06 m; weight 69.5 ± 7.2 kg) volunteered to participate in the study. Rowers were divided into two categories based on rowing experience: varsity (more than 1 year collegiate experience) and novice (less than 1 year collegiate experience). All rowers performed two continuous graded maximal oxygen consumption tests (familiarization and baseline) to establish maximal oxygen uptake (VO(2max)), peak power output, and power output at ventilatory threshold. Rowers then completed a critical velocity test, consisting of four time-trials at various distances (400 m, 600 m, 800 m, and 1000 m) on two separate days, with 15 min rest between trials. Following the critical velocity test, rowers completed a 2000-m time-trial. Absolute VO(2max) was the strongest predictor of 2000-m performance (r = 0.923) in varsity rowers, with significant correlations also observed for peak power output and critical velocity (r = 0.866 and r = 0.856, respectively). In contrast, critical velocity was the strongest predictor of 2000-m performance in novice rowers (r = 0.733), explaining 54% of the variability in performance. These findings suggest the critical velocity test may be more appropriate for evaluating performance in novice rowers.

  18. Ergometer training volume and previous injury predict back pain in rowing; strategies for injury prevention and rehabilitation.

    PubMed

    Wilson, Fiona; Gissane, Conor; McGregor, Alison

    2014-11-01

    The most commonly reported injury site in rowers is the lower back. Research in recent years has focused on epidemiology and biomechanical analyses to try and understand mechanisms that contribute to this injury's onset. Injury surveillance mainly comprises retrospective questionnaires and reviews of medical records with a lack of prospective data. Of studies that reported 12-month data, the incidence of low back pain ranged from 31.8 to 51% of the cohort. Of the limited studies that specifically examined low back pain in rowers, (1) history of lumbar spine injury and (2) volume of ergometer training were the most significant risk factors for injury onset. Studies of technique on the rowing ergometer have indicated the importance of lumbopelvic rotation during rowing. Greater pelvic rotation at either end of the stroke is ideal-as opposed to lumbar flexion and extension; this tends to be poorly demonstrated in novice rowers on ergometers. Furthermore, technique can deteriorate with the demands of rowing intensity and duration, which puts the rower returning from injury at additional risk. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  19. Comparing para-rowing set-ups on an ergometer using kinematic movement patterns of able-bodied rowers.

    PubMed

    Cutler, B; Eger, T; Merritt, T; Godwin, A

    2017-04-01

    While numerous studies have investigated the biomechanics of able-bodied rowing, few studies have been completed with para-rowing set-ups. The purpose of this research was to provide benchmark data for handle kinetics and joint kinematics for able-bodied athletes rowing in para- rowing set-ups on an indoor ergometer. Able-bodied varsity rowers performed maximal trials in three para-rowing set-ups; Legs, Trunk and Arms (LTA), Trunk and Arms (TA) and Arms and Shoulders (AS) rowing. The handle force kinetics of the LTA stroke were comparable to the values for able-bodied literature. Lumbar flexion at the catch, extension at the finish and total range of motion were, however, greater than values in the literature for able-bodied athletes in the LTA set-up. Additionally, rowers in TA and AS set-ups utilised more extreme ranges of motion for lumbar flexion, elbow flexion and shoulder abduction than the LTA set-up. This study provides the first biomechanical values of the para-rowing strokes for researchers, coaches and athletes to use while promoting the safest training programmes possible for para-rowing.

  20. A cycle ergometer test of maximal aerobic power.

    PubMed

    Myles, W S; Toft, R J

    1982-01-01

    An indirect test of maximal aerobic power (IMAP) was evaluated in 31 healthy male subjects by comparing it with a direct treadmill measurement of maximal aerobic power (VO2 max), with the prediction of VO2 max from heart rate during submaximal exercise on a cycle ergometer using Astrand's nomogram, with the British Army's Basic Fitness Test (BFT, a 2.4 km run performed in boots and trousers), and with a test of maximum anaerobic power. For the IMAP test, subjects pedalled on a cycle ergometer at 75 revs X min-1. The workload was 37.5 watts for the first minute, and was increased by 37.5 watts every minute until the subject could not continue. Time to exhaustion was recorded. Predicted VO2 max and times for BFT and IMAP correlated significantly (p less than 0.001) with the direct VO2 max: r = 0.70, r = 0.67 and r = 0.79 respectively. The correlation between direct VO2 max and the maximum anaerobic power test was significant (p less than 0.05) but lower, r = 0.44. Although lactate levels after direct VO2 max determination were significantly higher than those after the IMAP test, maximum heart rates were not significantly different. Submaximal VO2 values measured during the IMAP test yielded a regression equation relating VO2 and pedalling time. When individual values for direct and predicted VO2 max and times for BFT and IMAP were compared with equivalent standards, the percentages of subjects able to exceed the standard were 100, 65, 87, and 87 respectively. These data demonstrate that the IMAP test provides a valid estimate of VO2 max and indicate that it may be a practical test for establishing that an individual meets a minimum standard.

  1. Actual Versus Predicted Cardiovascular Demands in Submaximal Cycle Ergometer Testing.

    PubMed

    Hoehn, Amanda M; Mullenbach, Megan J; Fountaine, Charles J

    The Astrand-Rhyming cycle ergometer test (ARCET) is a commonly administered submaximal test for estimating aerobic capacity. Whereas typically utilized in clinical populations, the validity of the ARCET to predict VO2max in a non-clinical population, especially female, is less clear. Therefore, the purpose of this study was to determine the accuracy of the ARCET in a sample of healthy and physically active college students. Subjects (13 females, 10 males) performed a maximal cycle ergometer test to volitional exhaustion to determine VO2max. At least 48 hours later, subjects performed the ARCET protocol. Predicted VO2max was calculated following the ARCET format using the age corrected factor. There was no significant difference (p=.045) between actual (41.0±7.97 ml/kg/min) and predicted VO2max (40.3±7.58 ml/kg/min). When split for gender there was a significant difference between actual and predicted VO2 for males, (45.1±7.74 vs. 42.7±8.26 ml/kg/min, p=0.029) but no significant difference observed for females, (37.9±6.9 vs. 38.5±6.77 ml/kg/min, p=0.675). The correlation between actual and predicted VO2 was r=0.84, p<0.001 with an SEE= 4.3 ml/kg/min. When split for gender, the correlation for males was r=0.94, p<0.001, SEE=2.72 ml/kg/min; for females, r=0.74, p=0.004, SEE=4.67 ml/kg/min. The results of this study indicate that the ARCET accurately estimated VO2max in a healthy college population of both male and female subjects. Implications of this study suggest the ARCET can be used to assess aerobic capacity in both fitness and clinical settings where measurement via open-circuit spirometry is either unavailable or impractical.

  2. Comparison of a Double Poling Ergometer and Field Test for Elite Cross Country Sit Skiers

    PubMed Central

    Forbes, Scott C.; Craven, Bruce; Bhambhani, Yagesh

    2010-01-01

    Background Sport specific ergometers are important for laboratory testing (i.e. peak oxygen consumption (VO2)) and out of season training. Objectives The purpose of this study was to compare cardiorespiratory variables during exercise on a double poling ergometer to a field test in elite sit skiers. Methods Three male and four female athletes from the Canadian National / Developmental team (17-54 years of age, six with complete paraplegia and one with cerebral palsy) completed a field test and a double poling ergometer protocol separated by at least 24 hours. Both protocols consisted of three maximal trials of skiing of three minutes duration separated by 1.5 minutes of rest. A wireless metabolic system and heart rate monitor were used to measure cardiorespiratory responses [peak heart rate, peak VO2, and peak respiratory exchange ratio (RER)] during each test. Arterialized blood lactate was measured before the beginning of exercise, after each trial and at 5, 10 and 15 minutes post exercise. Results No significant differences existed between the field and ergometer tests for peak oxygen consumption (VO2) (field=34.7±5.5 mL·kg−1·min−1 vs. ergometer=33.4±6.9 mL·kg−1·min−1). Significantly higher peak heart rate and RER were found during the ergometer test. Significantly higher lactates were found during the ergometer test after trial 2 and trial 3. Conclusion The double poling ergometer is similar to a field test for evaluating peak VO2 in elite cross country sit skiers; however, the ergometer test elicits a higher heart rate and anaerobic response. PMID:21589660

  3. Muscle synergies during incremental rowing VO2max test of collegiate rowers and untrained subjects.

    PubMed

    Shaharudin, Shazlin; Agrawal, Sunil

    2016-09-01

    The purpose of this study was to evaluate the muscle synergies during incremental rowing VO2 max Test of collegiate rowers and untrained subjects. As a power endurance sport, high aerobic capacity was one of the determinants of rowing performance. The modulation of muscle recruitment patterns following specific physiological demands was an indication of the robustness of muscle synergies composition which was overlooked in previous studies. Ten male collegiate rowers and physically active untrained subjects were recruited. Muscle synergies were extracted from 16 rowing-specific muscles using Principal Component Analysis with varimax rotation. Incremental rowing VO2 max Test was performed on slides ergometer (SE). Rowing performance and physiological variables were analyzed. Rowers exerted greater power output, more energy expenditure and better rowing economy compared to untrained subjects. Rowers preferred to row slower with longer strokes compared to the untrained subjects. Three muscle synergies with high indices of similarity of waveform patterns were extracted in both groups. Significant association was found between muscle synergies and rowing economy. The findings of this study showed that muscle synergies were robust during aerobic-dominant activity for collegiate rowers and untrained subjects. Rowers and coaches could utilize the findings by emphasizing on muscle coordination training, which may enhance the rowing economy.

  4. Monitoring neuromuscular fatigue in team-sport athletes using a cycle-ergometer test.

    PubMed

    Wehbe, George; Gabett, Tim J; Dwyer, Dan; McLellan, Christopher; Coad, Sam

    2015-04-01

    To compare a novel sprint test on a cycle ergometer with a countermovement-jump (CMJ) test for monitoring neuromuscular fatigue after Australian rules football match play. Twelve elite under-18 Australian rules football players (mean ± SD age 17.5 ± 0.6 y, stature 184.7 ± 8.8 cm, body mass 75.3 ± 7.8 kg) from an Australian Football League club's Academy program performed a short sprint test on a cycle ergometer along with a single CMJ test 1 h prematch and 1, 24, and 48 h postmatch. The cycle-ergometer sprint test involved a standardized warm-up, a maximal 6-s sprint, a 1-min active recovery, and a 2nd maximal 6-s sprint, with the highest power output of the 2 sprints recorded as peak power (PP). There were small to moderate differences between postmatch changes in cycle-ergometer PP and CMJ PP at 1 (ES = 0.49), 24 (ES = -0.85), and 48 h postmatch (ES = 0.44). There was a substantial reduction in cycle-ergometer PP at 24 h postmatch (ES = -0.40) compared with 1 h prematch. The cycle-ergometer sprint test described in this study offers a novel method of neuromuscular-fatigue monitoring in team-sport athletes and specifically quantifies the concentric component of the fatigue-induced decrement of force production in muscle, which may be overlooked by a CMJ test.

  5. Determination of Aerobic Capacity via Cycle Ergometer Exercise Testing in Alzheimer's Disease.

    PubMed

    Bronas, Ulf G; Salisbury, Dereck; Kelly, Kaitlin; Leon, Arthur; Chow, Lisa; Yu, Fang

    2017-01-01

    Older adults with Alzheimer's disease (AD) may be unable to perform treadmill testing due to balance issues. We investigated whether older adults with AD could successfully complete a peak cycle ergometer test. Peak oxygen consumption (peak [Formula: see text]) assessed via a cycle ergometer test in 44 participants with AD (age 78.4 ± 6.8). Physical function was assessed via the incremental shuttle walk, 6-minute walk, and the Short Physical Performance Battery (SPPB). All participants completed the cycle ergometer test successfully. Peak [Formula: see text] was correlated with SPPB ( r = .35, P = .023), shuttle walk ( r = .35, P = .024), 6-minute walk ( r = .31, P = .05), and inversely with age ( r = -.4, P = .009). There was no correlation between peak [Formula: see text] and cognition. Older adults with AD are able to safely complete a peak cycle ergometer exercise testing protocol. We provide an individualized cycle ergometer test for determining aerobic capacity in older adults with AD who may be unable to perform treadmill testing due to balance or gait issues.

  6. The Reliability of Pedalling Rates Employed in Work Tests on the Bicycle Ergometer.

    ERIC Educational Resources Information Center

    Bolonchuk, W. W.

    The purpose of this study was to determine whether a group of volunteer subjects could produce and maintain a pedalling cadence within an acceptable range of error. This, in turn, would aid in determining the reliability of pedalling rates employed in work tests on the bicycle ergometer. Forty male college students were randomly given four…

  7. An MR-compatible bicycle ergometer for in-magnet whole-body human exercise testing.

    PubMed

    Jeneson, Jeroen A L; Schmitz, Joep P J; Hilbers, Peter A J; Nicolay, Klaas

    2010-01-01

    An MR-compatible ergometer was developed for in-magnet whole-body human exercise testing. Designed on the basis of conventional mechanically braked bicycle ergometers and constructed from nonferrous materials, the ergometer was implemented on a 1.5-T whole-body MR scanner. A spectrometer interface was constructed using standard scanner hardware, complemented with custom-built parts and software to enable gated data acquisition during exercise. High-quality 31P NMR spectra were reproducibly obtained from the medial head of the quadriceps muscle of the right leg of eight healthy subjects during two-legged high-frequency pedaling (80 revolutions per minute) at three incremental workloads, including maximal. Muscle phosphocreatine content dropped 82%, from 32.2+/-1.0 mM at rest to 5.7+/-1.1 mM at maximal workload (mean+/-standard error; n=8), indicating that the majority of quadriceps motor units were recruited. The cardiovascular load of the exercise was likewise significant, as evidenced by heart rates of 150 (+/-10%) beats per minute, measured immediately afterward. As such, the newly developed MR bicycling exercise equipment offers a powerful new tool for clinical musculoskeletal and cardiovascular MR investigation. The basic design of the ergometer is highly generic and adaptable for application on a wide selection of whole-body MR scanners.

  8. Correcting the Wingate test for changes in kinetic energy of the ergometer flywheel.

    PubMed

    Bassett, D R

    1989-12-01

    The rotating flywheel of a cycle ergometer possesses kinetic energy (KE) by virtue of its rotation about the center of mass. The energy released as the flywheel velocity (FV) decreases during the course of a Wingate test is used to accomplish mechanical work. The subject should not be "credited" with this work since the energy storage occurred prior to the start of the 30-s test. The total KE (KE-total) in the flywheel of a Monark ergometer was determined using the formula KEtotal = 1/2 I omega 2. The KE available to do work (KEwork) was measured by loading the ergometer with 1 Kp (9.8 N), spinning it at predetermined rates, and observing the number of revolutions completed as it coasted to a stop. The difference between KEtotal and KE-work was attributable to friction. The mechanical power supplied by the flywheel in any 5-s period of the Wingate test was found to be: Flywheel power (W) = .00185 (FVstart2-FVend2)/5s where FV is expressed in rpm. This indicates that Wingate test scores should be corrected by subtracting the flywheel power output from the total power output. The correction lowers peak power (PP), mean power (MP), and fatigue index (% fatigue) by 6.2%, 3.0%, and 6.6% in active male subjects (P less than 0.05).

  9. Validity of a Newly-Designed Rectilinear Stepping Ergometer Submaximal Exercise Test to Assess Cardiorespiratory Fitness.

    PubMed

    Zhang, Rubin; Zhan, Likui; Sun, Shaoming; Peng, Wei; Sun, Yining

    2017-09-01

    The maximum oxygen uptake (V̇O2 max), determined from graded maximal or submaximal exercise tests, is used to classify the cardiorespiratory fitness level of individuals. The purpose of this study was to examine the validity and reliability of the YMCA submaximal exercise test protocol performed on a newly-designed rectilinear stepping ergometer (RSE) that used up and down reciprocating vertical motion in place of conventional circular motion and giving precise measurement of workload, to determine V̇O2 max in young healthy male adults. Thirty-two young healthy male adults (32 males; age range: 20-35 years; height: 1.75 ± 0.05 m; weight: 67.5 ± 8.6 kg) firstly participated in a maximal-effort graded exercise test using a cycle ergometer (CE) to directly obtain measured V̇O2 max. Subjects then completed the progressive multistage test on the RSE beginning at 50W and including additional stages of 70, 90, 110, 130, and 150W, and the RSE YMCA submaximal test consisting of a workload increase every 3 minutes until the termination criterion was reached. A metabolic equation was derived from the RSE multistage exercise test to predict oxygen consumption (V̇O2) from power output (W) during the submaximal exercise test (V̇O2 (mL·min(-1) )=12.4 ×W(watts)+3.5 mL·kg(-1)·min(-1)×M+160mL·min(-1), R(2)= 0.91, standard error of the estimate (SEE) = 134.8mL·min(-1)). A high correlation was observed between the RSE YMCA estimated V̇O2 max and the CE measured V̇O2 max (r=0.87). The mean difference between estimated and measured V̇O2 max was 2.5 mL·kg(-1)·min(-1), with an SEE of 3.55 mL·kg(-1)·min(-1). The data suggest that the RSE YMCA submaximal exercise test is valid for predicting V̇O2 max in young healthy male adults. The findings show that the rectilinear stepping exercise is an effective submaximal exercise for predicting V̇O2 max. The newly-designed RSE may be potentially further developed as an alternative ergometer for assessing cardiorespiratory

  10. Exponential protocols for cardiopulmonary exercise testing on treadmill and cycle ergometer.

    PubMed

    Jamison, J P; Megarry, J; Riley, M

    2010-01-01

    An extended exponential exercise protocol was validated by comparing submaximal and maximal parameters with those obtained by linear protocol. Normal subjects (n = 16, 20-69 years) undertook maximal exercise tests on treadmill and cycle ergometer. The subjects had a wide range of exercise capacity, and all were accommodated by the protocol. Mean oxygen uptake (V(O2)) agreed between protocols at gas exchange anaerobic threshold (theta) (95% CI of difference -0.1 to +0.06 l min(-1)) and at peak (95% CI of difference -0.1 to +0.1 l min(-1)). Mean pre-thetaDeltaV(O2)/Deltawork rate (W) slope on the cycle ergometer agreed between protocols (95% CI of the difference -0.9 to +0.25 ml min(-1) W(-1)). Post-thetaDeltaV(O2)/DeltaW slope was steeper than pre-theta, and steeper by linear than by exponential protocol (P = 0.0001). It is concluded that the exponential protocol is valid for the measurement of submaximal and maximal exercise parameters in subjects with a wide range of exercise capacity.

  11. Validity of a Newly-Designed Rectilinear Stepping Ergometer Submaximal Exercise Test to Assess Cardiorespiratory Fitness

    PubMed Central

    Zhang, Rubin; Zhan, Likui; Sun, Shaoming; Peng, Wei; Sun, Yining

    2017-01-01

    The maximum oxygen uptake (V̇O2 max), determined from graded maximal or submaximal exercise tests, is used to classify the cardiorespiratory fitness level of individuals. The purpose of this study was to examine the validity and reliability of the YMCA submaximal exercise test protocol performed on a newly-designed rectilinear stepping ergometer (RSE) that used up and down reciprocating vertical motion in place of conventional circular motion and giving precise measurement of workload, to determine V̇O2 max in young healthy male adults. Thirty-two young healthy male adults (32 males; age range: 20-35 years; height: 1.75 ± 0.05 m; weight: 67.5 ± 8.6 kg) firstly participated in a maximal-effort graded exercise test using a cycle ergometer (CE) to directly obtain measured V̇O2 max. Subjects then completed the progressive multistage test on the RSE beginning at 50W and including additional stages of 70, 90, 110, 130, and 150W, and the RSE YMCA submaximal test consisting of a workload increase every 3 minutes until the termination criterion was reached. A metabolic equation was derived from the RSE multistage exercise test to predict oxygen consumption (V̇O2) from power output (W) during the submaximal exercise test (V̇O2 (mL·min-1 )=12.4 ×W(watts)+3.5 mL·kg-1·min-1×M+160mL·min-1, R2= 0.91, standard error of the estimate (SEE) = 134.8mL·min-1). A high correlation was observed between the RSE YMCA estimated V̇O2 max and the CE measured V̇O2 max (r=0.87). The mean difference between estimated and measured V̇O2 max was 2.5 mL·kg-1·min-1, with an SEE of 3.55 mL·kg-1·min-1. The data suggest that the RSE YMCA submaximal exercise test is valid for predicting V̇O2 max in young healthy male adults. The findings show that the rectilinear stepping exercise is an effective submaximal exercise for predicting V̇O2 max. The newly-designed RSE may be potentially further developed as an alternative ergometer for assessing cardiorespiratory fitness and the

  12. Design and testing of an MRI-compatible cycle ergometer for non-invasive cardiac assessments during exercise

    PubMed Central

    2012-01-01

    Background Magnetic resonance imaging (MRI) is an important tool for cardiac research, and it is frequently used for resting cardiac assessments. However, research into non-pharmacological stress cardiac evaluation is limited. Methods We aimed to design a portable and relatively inexpensive MRI cycle ergometer capable of continuously measuring pedalling workload while patients exercise to maintain target heart rates. Results We constructed and tested an MRI-compatible cycle ergometer for a 1.5 T MRI scanner. Resting and sub-maximal exercise images (at 110 beats per minute) were successfully obtained in 8 healthy adults. Conclusions The MRI-compatible cycle ergometer constructed by our research group enabled cardiac assessments at fixed heart rates, while continuously recording power output by directly measuring pedal force and crank rotation. PMID:22423637

  13. The 1,500-m Rowing Performance is Highly Dependent on Modified Wingate Anaerobic Test Performance in National-Level Adolescent Rowers.

    PubMed

    Maciejewski, Hugo; Rahmani, Abderrahmane; Chorin, Frédéric; Lardy, Julien; Giroux, Caroline; Ratel, Sébastien

    2016-11-01

    The aim of the current study was to determine whether the anaerobic performance assessed by a modified Wingate test could account for the 1,500-m rowing ergometer performance in young competitive rowers. Fourteen national-level adolescent rowers performed on a rowing ergometer i) a 30-s allout exercise (i.e., modified Wingate test) and ii) a 1,500-m all-out exercise (i.e., rowing performance). For each of these two exercises, the mean power output was considered as the main performance criterion (PWIN and P1500, respectively). PWIN was correlated to P1500 (r(2) = .83, p < .0001, β = 100%). Furthermore, the estimated total muscle mass was correlated to PWIN and P1500 (r(2) = .72 and r(2) = .83, p < .0001, β = 100%, respectively). The allometric scaling also indicated that total muscle mass accounts 62% for the relationship between PWIN and P1500. Our results highlight the importance of considering the contribution of total muscle mass and anaerobic energy pathways to 1,500-m rowing performance in competitive adolescent rowers. Therefore, the modified Wingate test could be used by rowing coaches to potentially identify talented young rowers.

  14. Effects of stroke resistance on rowing economy in club rowers post-season.

    PubMed

    Kane, D A; Mackenzie, S J; Jensen, R L; Watts, P B

    2013-02-01

    In the sport of rowing, increasing the impulse applied to the oar handle during the stroke can result in greater boat velocities; this may be facilitated by increasing the surface area of the oar blade and/or increasing the length of the oars. The purpose of this study was to compare the effects of different rowing resistances on the physiological response to rowing. 5 male and 7 female club rowers completed progressive, incremental exercise tests on an air-braked rowing ergometer, using either low (LO; 100) or high (HI; 150) resistance (values are according to the adjustable "drag factor" setting on the ergometer). Expired air, blood lactate concentration, heart rate, rowing cadence, and ergometer power output were monitored during the tests. LO rowing elicited significantly greater cadences (P<0.01) and heart rates (P<0.05), whereas rowing economy (J · L O(2) equivalents(-1)) was significantly greater during HI rowing (P<0.05). These results suggest that economically, rowing with a greater resistance may be advantageous for performance. Moreover, biomechanical analysis of ergometer rowing support the notion that the impulse generated during the stroke increases positively as a function of rowing resistance. We conclude that an aerobic advantage associated with greater resistance parallels the empirical trend toward larger oar blades in competitive rowing. This may be explained by a greater stroke impulse at the higher resistance.

  15. Reproducibility of incremental maximal cycle ergometer testing in patients with restrictive lung disease.

    PubMed Central

    Marciniuk, D. D.; Watts, R. E.; Gallagher, C. G.

    1993-01-01

    BACKGROUND--Exercise testing has become an important tool in the diagnosis and treatment of restrictive lung disease. The reproducibility of variables measured during exercise testing was examined in subjects with stable restrictive lung disease. METHODS--Six subjects, who had never previously undergone exercise testing, each underwent three maximal incremental exercise studies on a bicycle ergometer conducted during a 28 day period. RESULTS--Data collected at rest, before exercise, were not significantly different during the three study days. Comparison of results at the end of the exercise tests from the three studies also revealed no evidence of a significant learning effect. Reproducibility of exercise performance by subjects was assessed by the coefficient of variation. The mean within subject coefficient of variation at the end of the exercise tests was 5.6% for work rate, 7.9% for exercise duration, and 9.5% for dyspnoea. The mean within subject coefficient of variation obtained at the end of the exercise tests was 5.3% for oxygen uptake (VO2), 2.5% for oxygen saturation (SaO2), 4.0% for heart rate (HR), 5.5% for minute ventilation (VE), 5.8% for respiratory frequency (f), and 4.6% for tidal volume (VT). The mean within subject coefficient of variation at 40% and 70% of maximal work rates for VO2 was 5.7% and 5.6% respectively, for SaO2 1.3% and 1.5%, for HR 4.8% and 4.0%, for VE 6.3% and 6.6%, for f 10.1% and 7.8%, and for VT 6.0% and 4.5%. CONCLUSIONS--Variables measured during clinical exercise testing in subjects with restrictive lung disease are highly reproducible. No significant learning effect was found on repeated testing in subjects who had never previously undergone exercise testing. PMID:8236071

  16. [A study of cardiac dynamics during multistage exercise tests performed on a bycicle ergometer (author's transl)].

    PubMed

    Gobbato, F; Fiorito, A; Cornelio, G

    1977-05-01

    The authors analysed the behaviour of the mechanical systole (electromechanical systole; tension time, left ventricular ejection time), as well as of the diastole (both cardiac and hemodynamic diastole) during exercise tests performed on a bycicle ergometer, with 40, 80, 120 watt workloads. The mechanical systole--as well as its components--duration is influenced, during exercise test, by both heart rate and stroke volume--pulse pressure being assumed as an indirect index of the latter. The study of the correlation between the two above mentioned parameters has a great importance in evaluating the cardiac pump efficiency both in health and disease. The study of the behaviour of diastole is likewise very important, as it provides useful information concerning: a) the length of the cardiac muscle post-exercise recovery phase; b) the coronary available perfusion time; c) the Windkessel (arterial bellows) emptying time. Moreover, the blood pressure fall rate in diastole is an useful indirect measure of the peripheral resistance changes during muscular work. A statistical analysis is made and the correlation coefficients and the regression equations between the various parameters are defined.

  17. Reliability and discriminative ability of a modified Wingate rowing test in 12- to 18-year-old rowers.

    PubMed

    Mikulic, Pavle; Emersic, Davor; Markovic, Goran

    2010-11-01

    We evaluated (1) the test-retest reliability of the Wingate test conducted on a rowing ergometer, and (2) the sensitivity of this test in determining the differences in performance attained by 12- to 18-year-old rowers. Altogether, 297 male rowers aged 12.0-18.9 years (mean ± s: 14.8 ± 1.7) completed a maximal 30-s test on a rowing ergometer, and 80 rowers representing all age groups were retested after 5-7 days. No change was evident in participants' performance in terms of mean power output (P = 0.726; Cohen's d = 0.04), maximal power output (P = 0.567; Cohen's d = 0.06), and minimum power output (P = 0.318; Cohen's d = 0.11) in the second test. The intra-class correlation coefficients were high (≥0.973) and coefficients of variation were low (≤7.3%). A series of analyses of variance were used to compare the performances among 12- to 18-year-old rowers, and age-related increases in performance were evident (P < 0.001; Cohen's d = 1.91-1.96). The age-related increases in performance were similar, although reduced, when the effects of body mass were partitioned out when using analysis of covariance (P < 0.001; Cohen's d = 0.82-0.85). The results suggest that: (1) the described test is reliable and can be used for maximal-intensity exercise assessment in youth rowing, and (2) it discriminates performance among 12- to-18-year-old rowers.

  18. Correlation between the results of three physical fitness tests (endurance, strength, speed) and the output measured during a bicycle ergometer test in a cohort of military servicemen.

    PubMed

    Sammito, Stefan; Gundlach, Nils; Böckelmann, Irina

    2016-01-01

    Physical fitness tests are widely used to assess endurance, sprint ability, coordination and/or strength. The objective of the present study was to analyze the degree to which the results of the Bundeswehr Basis Fitness Test (BFT)--a physical fitness test comprising a sprint test (11 × 10-m shuttle test), a flexed-arm hang test and a 1000-m run--are consistent with the output measured during a bicycle ergometer test. The number of false-positive and false-negative results with regard to the assessment of physical fitness were also examined. As part of a retrospective study, health assessments from 323 reenlistment examinations were evaluated regarding the output measured during a bicycle ergometer test and compared with the BFT results of the candidates. Overall, a good correlation was shown between the bicycle ergometer test results and the results achieved in the BFT disciplines. All three disciplines of the BFT showed a highly significant correlation with the relative output achieved during the bicycle ergometer test (P < 0.001), and also, the overall BFT score was highly significantly correlated (P < 0.001). The overall rate of false-positive and false-negative results was 4.0 %. The BFT results measured in the three physical fitness test items were highly correlated with the output measured during the bicycle ergometer tests. The rate of false-positive and false-negative results was low. The test items thus represent an appropriate measurement instrument because the test items require few equipment and less time. Additionally, a large number of subjects can be assessed. We suggest that it would be more useful to assess the physical fitness of this special group exclusively on the basis of the BFT instead of using the bicycle ergometer test.

  19. [Obtaining a formula that improves maximum oxygen consumption estimation in cycle ergometer exercise tests].

    PubMed

    Romero-Farina, G; Candell-Riera, J; Bofill, J M; Aguadé-Bruix, S; Pizzi, M N; García-Dorado, D

    2015-01-01

    To evaluate if the estimation of the maximal oxygen consumption (MO2C) in METs (metabolic equivalents) by means of the table proposed in the guidelines of the Spanish Society of Cardiology is a sufficiently reliable method when applied to the bicycle exercise test. The MO2C in METs was obtained by gas-exchange analysis on bicycle ergometer tests in 97 healthy subjects (group i). It was compared with the estimate of METs using the table in which only watts and patient's weight were included. A better-adjusted formula was validated in 289 subjects with normal exercise myocardial perfusion gated-SPECT (group ii) using the introduction of clinical and ergometric variables. In group i individuals a good correlation between METs estimated with the table and those obtained through gas-exchange analysis (CCI: 0.93) was observed. However, the best adjusted formula to estimate METs in group ii subjects included watts, body mass index (BMI), age and gender (METS=11.820-0.054×age-0.189×BMI+1.031×gender+0.020×watts) (women: 0, men: 1). This formula allowed the reclassification of 46.9% of group ii subjects into the category <5METs versus the estimation by table. Estimating the METs with the conventional table is reliable. However, the best adjustment in subjects with normal bicycle exercise SPECT was obtained when, in addition to watts and BMI, age and gender were also considered. Copyright © 2014 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  20. Development of a rowing-specific VO2max field test.

    PubMed

    Huntsman, Heather D; DiPietro, Loretta; Drury, Daniel G; Miller, Todd A

    2011-06-01

    The purpose of this study was to develop an aerobic capacity test for rowers using minimal equipment that could be used in the field. Thirty rowers (15 men and 15 women) between the ages of 18 and 26 years were recruited on a volunteer basis from the District of Columbia metro area. The testing protocol consisted of a maximum of 7 2-minute stages on a rowing ergometer, separated by 30-second breaks where lactic acid concentrations were analyzed. Starting intensity for men was 200 W, although women started at 150 W, and each stage increased by 50 W. Expired gasses were collected during the test, and athletes were asked to row until maximal volition so that the directly measured VO2max could be compared to predicted values. Peak heart rates from each completed stage were plotted, and regression equations were calculated to predict VO2max. Separate regression equations were calculated for men and women. The predicted VO2max values were approximately 23 and 25% lower than what was actually achieved for men and women, respectively. Heart rate was a stronger correlate of VO2max in men compared with in women. Among men, we observed a moderate and statistically significant correlation (r = 0.55; p = 0.05), whereas among women, no such agreement was observed (r = -0.05; p > 0.85). The principle finding of this study was that the test was adequate in predicting VO2max in men but was inadequate in its prediction in women. With slight modifications to the testing protocol, stronger correlations and a more accurate prediction of VO2max is expected in men.

  1. Stage duration and increase of work load in incremental testing on a cycle ergometer.

    PubMed

    Stockhausen, W; Grathwohl, D; Bürklin, C; Spranz, P; Keul, J

    1997-01-01

    Any variation of the test protocol for incremental testing (IT) in cycle ergometry may affect the accuracy of the determination of anaerobic threshold (AnT). For lactate threshold concepts, indicating the maximum lactate steady-state (max Lass), the formation of the quasi-steady-state (QSS=95% of steady-state level) is evident. Previous studies have not specified the time that it takes for blood lactate to stabilize following incremental changes in WL. The purpose of this study was to identify the minimum duration of exercise necessary to establish QSS following various increments in WL (10, 20, 30, 40 and 50 W). Eight male endurance-trained cyclists [relative maximal oxygen consumption = 64.8 (4.2) ml x kg(-1) x min(-1)] performed three different exercise tests on a cycle ergometer: (1) an exhaustive IT with a starting WL of 100 W, followed by 20-W increments every 3 min; (2) a threshold test with 20-W increments every 9 min to determine the MaxLaSS; and (3) five incremental exercise tests (from 100/110 W, with 20-W increments every 3 min) with a final 10-, 20-, 30-, 40- or 50- W increment lasting 10 min, at 10 W below MaxLaSS (T10-T50 experiments). The time constant of lactate kinetics (tau), the time constant of lactate elimination, and the time taken to elicite QSS, defined as 95% of the time taken to reach steady-state level (t95%), were calculated in the T10-T50 experiments. The tau and t95% increased significantly with WL increment size: the correlation was not linear. Smaller WL increments required proportionally longer durations. Mean (SD) t95% values (min:s) were 1:57 (0:27) (T10), 2:58 (0.16) (T20), 4:08 (0:23) (T30), 4:45 (0:45) (T40) and 5:06 (0:43) (T50). The application of these references in IT protocols may lead to an extension of total test duration, particularly with smaller increments. Therefore, lactate threshold modelling, the training status of the athletes and comparability with lactate measurements obtained during training events should be

  2. Application of force-velocity cycle ergometer test and vertical jump tests in the functional assessment of karate competitor.

    PubMed

    Ravier, G; Grappe, F; Rouillon, J D

    2004-12-01

    The aim of this study was to analyze the links between tests performances (vertical jump and force-velocity sprint on cycle ergometer) and 2 different karate level groups in order to propose a test battery adjusted to karate. Twenty-two karate competitors (10 national junior team (IJ) and 12 national competition level (NL)) performed 4 maximal squat jumps (SJ), 4 maximal counter movement jumps (CMJ) on an ergojump and 3 8-s sprints on a friction braked cycle ergometer (friction loads of 0.5, 0.7, 0.9 N x kg(-1)). The maximal theoretical force (F(0)) and velocity (V(0)), the maximal power output (P(max)) and the optimal pedalling velocity (V(opt)) were derived from both the force -- velocity and the power -- velocity relationships plotted from all the 3 friction loads data. V(0), F(0), V(opt), P(max) and the best SJ and CMJ, were compared between IJ and NL groups. The IJ group was characterised by significantly higher values of V(0) (+13%) and SJ (+14.3%) compared to NL group, whereas no significant difference was observed between groups for F(0). Thus, karate performance would depend on maximal velocity and explosive strength. In addition, V(opt) was significantly higher in IJ group compared to NL group (135.4 rpm vs 119.2 rpm, p<0.001). Although based upon indirect evidence, these results accounted for mechanical functional capabilities of experts which could be particularly valuable when monitoring training of karate competitor. A force-velocity and a vertical jump tests may be applied in the functional assessment of karate competitor.

  3. Measures of rowing performance.

    PubMed

    Smith, T Brett; Hopkins, Will G

    2012-04-01

    Accurate measures of performance are important for assessing competitive athletes in practi~al and research settings. We present here a review of rowing performance measures, focusing on the errors in these measures and the implications for testing rowers. The yardstick for assessing error in a performance measure is the random variation (typical or standard error of measurement) in an elite athlete's competitive performance from race to race: ∼1.0% for time in 2000 m rowing events. There has been little research interest in on-water time trials for assessing rowing performance, owing to logistic difficulties and environmental perturbations in performance time with such tests. Mobile ergometry via instrumented oars or rowlocks should reduce these problems, but the associated errors have not yet been reported. Measurement of boat speed to monitor on-water training performance is common; one device based on global positioning system (GPS) technology contributes negligible extra random error (0.2%) in speed measured over 2000 m, but extra error is substantial (1-10%) with other GPS devices or with an impeller, especially over shorter distances. The problems with on-water testing have led to widespread use of the Concept II rowing ergometer. The standard error of the estimate of on-water 2000 m time predicted by 2000 m ergometer performance was 2.6% and 7.2% in two studies, reflecting different effects of skill, body mass and environment in on-water versus ergometer performance. However, well trained rowers have a typical error in performance time of only ∼0.5% between repeated 2000 m time trials on this ergometer, so such trials are suitable for tracking changes in physiological performance and factors affecting it. Many researchers have used the 2000 m ergometer performance time as a criterion to identify other predictors of rowing performance. Standard errors of the estimate vary widely between studies even for the same predictor, but the lowest

  4. Effects of an Aerobic Rowing Training Regimen in Young Adults with Down Syndrome.

    ERIC Educational Resources Information Center

    Varela, Ana Maria; Sardinha, Luis Bettencount; Pitetti, Kenneth H.

    2001-01-01

    Eight young adult males with Down syndrome received a 16-week rowing ergometry training regimen. Following training, no changes in cardiovascular fitness were found but participants did achieve significantly higher levels of work performance on both treadmill and rowing ergometer tests than did a control group. (Contains references.) (Author/DB)

  5. Physical efficiency and activity energy expenditure in term pregnancy females measured during cardiopulmonary exercise tests with a supine cycle ergometer.

    PubMed

    Jędrzejko, Maciej; Nowosielski, Krzysztof; Poręba, Ryszard; Ulman-Włodarz, Izabela; Bobiński, Rafał

    2016-12-01

    To evaluate physical efficiency and activity energy expenditure (AEE) in term pregnancy females during cardiopulmonary exercise tests with a supine cycle ergometer. The study comprised 22 healthy full-term pregnancy women with uncomplicated pregnancies hospitalized in the Department of Gynecology and Obstetrics, Specialist Teaching Hospital in Tychy, Poland. All subjects underwent cardiopulmonary exercise tests (CPET) on a supine cycle ergometer. The 12-min, three-stage, progressive, symptom-limited submaximal test protocol (up to 80% HRmax) was used. Pulsometry was used to record HR on a beat-to-beat analysis and to calculate AEE. Respiratory responses were measured by ergospirometer and a computer system on a breath-by-breath basis at rest, during exercise and at restitution. In the studied population, VO2max was established at the level of 2.19 ± 0.33 L/min in ergospirometry and 2.04 ± 025 L/min in pulsometry. Physical efficiency calculated for sub-maximal exercise by use of the Davis equation was 30.52 ± 0.12%. AEE, based on VO2 in various phases of the CPET, was 0.47, 0.71 and 0.88 L/min for phases 25, 50 and 75 W. Based on ergospirometer readouts, AEE was 10.60, 16.11 and 20.94 kJ/min for phases 25, 50 and 75 W. Overall mean AEE (determined by pulsometry) was 10.59  kJ/min. CPET testing did not have any negative effect upon the health or life of the neonates involved in the study. Submaximal CPET up to 80% HRmax with a supine cycle ergometer is a safe and precise method for assessing work efficiency in term pregnancy women.

  6. Identification of critical intensity from a single lactate measure during a 3-min, submaximal cycle-ergometer test.

    PubMed

    Fontana, Federico Y; Colosio, Alessandro L; Keir, Daniel A; Murias, Juan M; Pogliaghi, Silvia

    2016-12-06

    We tested the hypothesis that critical intensity in cycling can be determined from a single delta blood lactate in the third minute of a submaximal cycle ergometer trial. Fourteen healthy young men performed four to six constant-power-output trials on a cycle ergometer to the limit of tolerance. Critical intensity was calculated via a linear model and subsequently validated. Lactate was measured at baseline and at 3 min from exercise onset. Delta lactate was the difference between these measures. Based on individual trials, we obtained the delta lactate-% validated critical intensity relationship and thereafter an estimate of critical intensity was computed. Validated and estimated critical intensity were compared by effects sizes, paired-sample t-test and Bland-Altman analysis. Delta lactate was a linear function of the intensity of exercise, expressed as % validated critical intensity (R(2) = 0.89). Estimated critical intensity was not different from (d = 0.03, P = 0.98) and highly correlated with (R(2) = 0.88) validated critical intensity. The bias between measures was 0.03 W (≠0) with a precision of 7 W. The results suggest that critical intensity in cycling can be accurately and precisely determined from delta lactate during a sub-maximal trial and so provides a practical and valid alternative to direct determination.

  7. Design and testing of a tandem row pump inducer

    NASA Technical Reports Server (NTRS)

    Etter, R. J.

    1974-01-01

    The design and testing of a tandem row pump inducer having a supercavitating first stage with a 0.60 hub ratio is presented. The second stage tested was a helical impeller with a 0.70 hub ratio. A cubic arc transition was utilized to accomplish the hub change. The first stage had two blades and the free-vortex design approach was empirically modified based on previous experience. The recommended second stage design having four blades and using cambered blade section is presented but the model was not built or tested. The more simple helix was built instead to reduce cost. Data taken included head generation, cavitation observations and unsteady head fluctuations over the 0-100Hz range.

  8. Effects of a Non-Circular Chainring on Sprint Performance During a Cycle Ergometer Test.

    PubMed

    Hintzy, Frédérique; Grappe, Frédéric; Belli, Alain

    2016-06-01

    Non-circular chainrings have been reported to alter the crank angular velocity profile over a pedal revolution so that more time is spent in the effective power phase. The purpose of this study was to determine whether sprint cycling performance could be improved using a non-circular chainring (Osymetric: ellipticity 1.25 and crank lever mounted nearly perpendicular to the major axis), in comparison with a circular chainring. Twenty sprint cyclists performed an 8 s sprint on a cycle ergometer against a 0.5 N/kg(-1) friction force in four crossing conditions (non-circular or circular chainring with or without clipless pedal). Instantaneous force, velocity and power were continuously measured during each sprint. Three main characteristic pedal downstrokes were selected: maximal force (in the beginning of the sprint), maximal power (towards the middle), and maximal velocity (at the end of the sprint). Both average and instantaneous force, velocity and power were calculated during the three selected pedal downstrokes. The important finding of this study was that the maximal power output was significantly higher (+ 4.3%, p < 0.05) when using the non-circular chainring independent from the shoe-pedal linkage condition. This improvement is mainly explained by a significantly higher instantaneous external force that occurs during the downstroke. Non-circular chainring can have potential benefits on sprint cycling performance. Key pointsThe Osymetric non-circular chainring significantly maximized crank power by 4.3% during sprint cycling, in comparison with a circular chainring.This maximal power output improvement was due to significant higher force developed when the crank was in the effective power phase.This maximal power output improvement was independent from the shoe-pedal linkage condition.Present benefits provided by the non-circular chainring on pedalling kinetics occurred only at high cadences.

  9. Effects of a Non-Circular Chainring on Sprint Performance During a Cycle Ergometer Test

    PubMed Central

    Hintzy, Frédérique; Grappe, Frédéric; Belli, Alain

    2016-01-01

    Non-circular chainrings have been reported to alter the crank angular velocity profile over a pedal revolution so that more time is spent in the effective power phase. The purpose of this study was to determine whether sprint cycling performance could be improved using a non-circular chainring (Osymetric: ellipticity 1.25 and crank lever mounted nearly perpendicular to the major axis), in comparison with a circular chainring. Twenty sprint cyclists performed an 8 s sprint on a cycle ergometer against a 0.5 N/kg-1 friction force in four crossing conditions (non-circular or circular chainring with or without clipless pedal). Instantaneous force, velocity and power were continuously measured during each sprint. Three main characteristic pedal downstrokes were selected: maximal force (in the beginning of the sprint), maximal power (towards the middle), and maximal velocity (at the end of the sprint). Both average and instantaneous force, velocity and power were calculated during the three selected pedal downstrokes. The important finding of this study was that the maximal power output was significantly higher (+ 4.3%, p < 0.05) when using the non-circular chainring independent from the shoe-pedal linkage condition. This improvement is mainly explained by a significantly higher instantaneous external force that occurs during the downstroke. Non-circular chainring can have potential benefits on sprint cycling performance. Key points The Osymetric non-circular chainring significantly maximized crank power by 4.3% during sprint cycling, in comparison with a circular chainring. This maximal power output improvement was due to significant higher force developed when the crank was in the effective power phase. This maximal power output improvement was independent from the shoe-pedal linkage condition. Present benefits provided by the non-circular chainring on pedalling kinetics occurred only at high cadences. PMID:27274658

  10. Changes in Rowing Technique Over a Routine One Hour Low Intensity High Volume Training Session

    PubMed Central

    Mackenzie, Hugh A.M.; Bull, Anthony M.J.; McGregor, Alison H.

    2008-01-01

    High volume low intensity training sessions such as one hour rowing ergometer sessions are frequently used to improve the fitness of elite rowers. Early work has suggested that technique may decline over this time period. This study sought to test the hypothesis that “elite rowers can maintain technique over a one hour rowing ergometer session”. An electromagnetic device, in conjunction with a load cell, was used to assess rowing technique in terms of force generation and spinal kinematics in six male elite sweep oarsmen (two competed internationally and the remainder at a club senior level). All subjects performed one hour of rowing on a Concept II indoor rowing ergometer using a stroke rate of 18-20 strokes per minute and a heart rate ranging between 130-150 beats per minute, following a brief 5 minute warm- up. Recordings of rowing technique and force were made every 10 minutes. The elite group of rowers were able to sustain their rowing technique and force parameters over the hour session. Subtle changes in certain parameters were observed including a fall in force output of approximately 10N after the first seven minutes of rowing, and a change in leg compression of three degrees at the end of the one hour rowing piece which corresponded with a small increase in anterior rotation of the pelvis. However, it is unclear if such changes reflect a “warm-up” effect or if they are indicative of early signs of fatigue. These findings suggest that low intensity high volume ergometer rowing sessions do not have a detrimental effect on the technique of a group of experienced and highly trained rowers. Key pointsElite rowers do not demonstrate changes in rowing kinematics over and hour rowing piece.Rowers require an adequate warm-up to establish their technique. PMID:24149955

  11. Comparison between parameters from maximal cycle ergometer test first without respiratory gas analysis and thereafter with respiratory gas analysis among healthy prepubertal children.

    PubMed

    Tompuri, Tuomo T; Lintu, Niina; Soininen, Sonja; Laitinen, Tomi; Lakka, Timo Antero

    2016-06-01

    It is important to distinguish true and clinically relevant changes and methodological noise from measure to measure. In the clinical practice, maximal cycle ergometer tests are typically performed first without respiratory gas analysis and thereafter, if needed, with respiratory gas analysis. Therefore, we report a comparison of parameters from maximal cycle ergometer exercise tests that were done first without respiratory gas analysis and thereafter with it in 38 prepubertal and healthy children (20 girls, 18 boys). The Bland-Altman method was used to assess agreement in maximal workload (WMAX), heart rate (HR), and systolic blood pressure (SBP) between rest and maximum. Girls achieved higher WMAX in the exercise tests with respiratory gas analysis compared with exercise tests without respiratory gas analysis (p = 0.016), whereas WMAX was similar in the tests among boys. Maximal HR (proportional offset, -1%; coefficients of variation, 3.3%) and highest SBP (proportional offset, 3%; coefficients of variation, 10.6%) were similar in the tests among children. Precision and agreement for HR improved and precision for SBP worsened with increasing exercise intensity. Heteroscedasticity was not observed for WMAX, HR, or SBP. We conclude that maximal cycle ergometer tests without and with respiratory gas analysis can be used consecutively because measurement of respiratory gases did not impair performance or have a significant effect on the maximality of the exercise tests. Our results suggest that similar references can be used for children who accept or refuse using a mask during a maximal exercise test.

  12. A new submaximal cycle ergometer test for prediction of VO2max.

    PubMed

    Ekblom-Bak, E; Björkman, F; Hellenius, M-L; Ekblom, B

    2014-04-01

    Maximal oxygen uptake (VO2max) is an important, independent predictor of cardiovascular health and mortality. Despite this, it is rarely measured in clinical practice. The aim of this study was to create and evaluate a submaximal cycle ergometry test based on change in heart rate (HR) between a lower standard work rate and an individually chosen higher work rate. In a mixed population (n = 143) with regard to sex (55% women), age (21-65 years), and activity status (inactive to highly active), a model included change in HR per unit change in power, sex, and age for the best estimate of VO2max. The association between estimated and observed VO2max for the mixed sample was r = 0.91, standard error of estimate = 0.302 L/min, and mean measured VO2max = 3.23 L/min. The corresponding coefficient of variation was 9.3%, a significantly improved precision compared with one of the most commonly used submaximal exercise tests, the Åstrand test, which in the present study was estimated to be 18.1%. Test-retest reliability analysis over 1 week revealed no mean difference in the estimated VO2max (-0.02 L/min, 95% confidence interval: -0.07-0.03). The new test is low-risk, easily administered, and valid for a wide capacity range, and is therefore suitable in situations as health evaluations in the general population.

  13. Optimal loads for a 30-s maximal power cycle ergometer test using a stationary start.

    PubMed

    Vargas, Nicole T; Robergs, Robert A; Klopp, Dawn M

    2015-05-01

    A stationary start modification to the Wingate Anaerobic Test (WAnT) has become increasingly common. The aim of the present study was to determine whether the traditional 85 g kg(-1) body weight (BW) load (TRAD), or an individualized optimal load (OPT), is more suitable for obtaining peak and mean power outputs (PPO and MPO, respectively) for a stationary start. Twelve recreationally active males and 10 females (mean age 30 ± 9.1 and 25 ± 5.5 years, respectively) completed three trials. The first determined the OPT load and included a familiarization of the 30-s stationary start test, followed by two randomized sessions testing the OPT and TRAD loads during the 30-s stationary start test on separate days. For each test, measures of power (watts), time, and cadence were collected to determine PPO, MPO, rate of power decline (rPD) and time to peak power (TtPP). All power data were corrected for flywheel moment of inertia. Results revealed significant differences between OPT and TRAD load settings for males (95.1 ± 10.7 and 85.06 ± 0.40 g kg(-1) BW; p = 0.008) but not for females (84.71 ± 8.72 and 85.2 ± 0.61 g kg(-1) BW; p = 0.813). Relative PPO was not different for OPT or TRAD loads for males (p = 0.485) or females (p = 0.488). It is not necessary to use an OPT load setting to acquire maximal PO for a 30-s cycle test using a stationary start. Instead, the traditional 85 g kg(-1) BW loading is suitable for both males and females.

  14. Mechanically versus electro-magnetically braked cycle ergometer: performance and energy cost of the Wingate Anaerobic Test.

    PubMed

    Micklewright, D; Alkhatib, A; Beneke, R

    2006-04-01

    Performance and metabolic profiles of the Wingate Anaerobic Test (WAnT) were compared between a mechanically resisted (ME) and an electro-magnetically braked (EE) cycle ergometer. Fifteen healthy subjects (24.0+/-3.5 years, 180.5+/-6.1 cm, 75.4+/-11.9 kg) performed a WAnT on ME, and EE 3 days apart. Performance was measured as peak power (PP), minimum power (MP), mean power (AP), time to PP (TTPP), fatigue rate (FR), and maximum cadence (RPM(MAX)). Lactic (W (LAC)) and alactic (W (PCR)) anaerobic energy were calculated from net lactate appearance and the fast component of post-exercise oxygen uptake. Aerobic metabolism (W (AER)) was calculated from oxygen uptake during the WAnT. Total energy cost (W (TOT)) was calculated as the sum of W (LAC), W (PCR), and W (AER). There was no difference between ME and EE in PP (873+/-159 vs. 931+/-193 W) or AP (633+/-89 vs. 630+/-89 W). In the EE condition TTPP (2.3+/-0.7 vs. 4.3+/-0.7 s) was longer (P<0.001), MP (464+/-78 vs. 388+/-57 W) was lower (P<0.001), FR (15.2+/-5.2 vs. 20.5+/-6.8%) was higher (P<0.005), and RPM(MAX) (168+/-18 vs. 128+/-15 rpm) was slower (P<0.001). There was no difference in W (TOT) (1,331+/-182 vs. 1,373+/-120 J kg(-1)), W (AER) (292+/-76 vs. 309+/-72 J kg(-1)), W (PCR) (495+/-153 vs. 515+/-111 J kg(-1)) or W (LAC) (545+/-132 vs. 549+/-141 J kg(-1)) between ME and EE devices. The EE produces distinctly different performance measures but valid metabolic WAnT results that may be used to evaluate anaerobic fitness.

  15. Maximal Oxygen Uptake cannot be Determined in the Incremental Phase of The Lactate Minimum Test on a Cycle Ergometer.

    PubMed

    Miyagi, Willian Eiji; Malta, Elvis de Souza; Zagatto, Alessandro Moura

    2015-06-01

    The aim of this study was to investigate the maximal oxygen uptake (VO2MAX) determined using the incremental phase of the lactate minimum test (LM) on a cycle ergometer. Fifteen trained men were submitted to a graded exercise test (GXT) to evaluate the VO2MAX and LM. The total durations of the GXT and LM were 11.2±1.8 minutes (CI95%:10.2-12.3 minutes) and 25.3±3.2 minutes (CI95%:23.5-27.0), respectively. For the variables measured at exhaustion in both the GXT and LM, the oxygen uptake (54.6 ± 8.1 ml·kg(-1)·min(-1) vs 50.0 ± 7.7 ml·kg(-1)·min(-1)), carbon dioxide production (66.1 ± 7.5 ml·kg(-1)·min(-1) vs 50.4 ± 8.0 ml·kg(-1)·min(-1)), ventilation (153.9 ± 19.0 L·min(-1) vs 129.9 ± 22.9 L·min(-1)), respiratory exchange ratio (1.22 ± 0.10 vs1.01 ± 0.05), maximal power output achieved (331.6 ± 45.8 W vs 242.4 ± 41.0 W), heart rate (183.1 ± 6.9 bpm vs175.9 ± 10.6 bpm) and lactate (10.5 ± 2.3 mmol·L(-1) vs 6.6 ± 2.2 mmol·L(-1)) were statistically lower in the LM (p < 0.05). However, the values of rating of perceived exertion (17.6 ± 2.5 for GXT and 17.2 ± 2.3 for LM) did not differ (ES = 0.12 and CV = 7.8%). There was no good agreement between the values of the VO2MAX from the GXT and VO2PEAK from the LM, as evidenced in the Bland-Altman plot (4.7 ml·kg(-1)·min(-1) and 0.34 L·min(-1) of mean differences, respectively), as well as the high values of the upper and lower limits of agreement. We conclude that the VO2PEAK values obtained in the incremental phase of the LM underestimate the VO2MAX. Key pointsThe VO2MAX is not attained during the incremental phase of the lactate minimum test;The physiological responses at exhaustion during LM are not similar to physiological responses measured during GXT;There is a weak agreement between the peak VO2 measured at exhaustion during LM and the VO2MAX measured during GXT.

  16. Dynamic torquemeter calibration of bicycle ergometers.

    PubMed

    Russell, J C; Dale, J D

    1986-09-01

    Bicycle ergometers as widely used in both clinical testing and exercise physiology studies are mechanical, hydraulic, or electromechanical devices. They are thus subject to change and error, creating a need for repeated calibration. We have developed a compact inexpensive torquemeter that permits dynamic calibration of the entire range of an ergometer. The torquemeter continuously measures the input torque at the pedal shaft of the ergometer and thus includes all work done in the drivetrain. It also permits adjustment of electrically braked ergometers to a specified torque using internal adjustments to give correct scale readings. The torquemeter depends on a high carbon steel torsion spring whose ends are rotated in angular deflection by increasing applied torque. Relative rotation is sensed through a multiturn potentiometer, the resistance of which is measured externally through a slip ring contact.

  17. Ergometer calibrator. [for any ergometer utilizing rotating shaft

    NASA Technical Reports Server (NTRS)

    Gause, R. L. (Inventor)

    1975-01-01

    An apparatus is presented for accurately calibrating ergometers so that the work rate produced by the particular ergometer being calibrated is accurate. The apparatus includes a dc motor which is coupled directly to the ergometer for rotating it at various speeds. Positioned on the shaft between the dc motor and the ergometer is a torque sensor and tachometer, which feed signals to a power computer for subsequent recording. A speed controller is utilized with the dc motor.

  18. Calibration Variability of 15 High Use Life Fitness Cycle Ergometers

    DTIC Science & Technology

    2013-12-02

    regression of Calories on Watts for the Life Fitness cycle ergometers , the regression equation (Calories = 0.7204 * Watts + 13.04) can be used to compute...DATES COVERED - 4. TITLE AND SUBTITLE Calibration Variability of 15 High Use Life Fitness Cycle Ergometers 5a. CONTRACT NUMBER 5b. GRANT...Classic and the Life Fitness 95C Version 4 cycle ergometers as a cardio testing alternative to the 1.5 mile run. The cardio alternative test involves

  19. Validity of the Modified Conconi Test for Determining Ventilatory Threshold During On-Water Rowing

    PubMed Central

    Cabo, Jorge Villamil; Martinez-Camblor, Pablo; del Valle, Miguel

    2011-01-01

    The objectives of this study were to design a field test based on the Conconi protocol to determine the ventilatory threshold of rowers and to test its reliability and validity. A group of sixteen oarsmen completed a modified Conconi test for on-water rowing. The reliability of the detection of the heart rate threshold was evaluated using heart rate breaking point in the Conconi test and retest. Heart rate threshold was detected in 88.8% of cases in the test-retest. The validity of the modified Conconi test was evaluated by comparing the heart rate threshold data acquired with that obtained in a ventilatory threshold test (VT2). No significant differences were found for the values of different intensity parameters i.e. heart rate (HR), oxygen consumption (VO2), stroke rate (SR) and speed (S) between the heart rate threshold and the ventilatory threshold, (170.9 ± 6.8 vs. 169.3 ± 6.4 beats·min-1; 42.0 ± 8.6 vs. 43.5 ± 8.3 ml·kg-1·min-1; 25.8 ± 3.3 vs. 27.0 ± 3.2 strokes·min-1 and 14.4 ± 0.8 vs. 14.6 ± 0.8 km·h-1). The differences in averages obtained in the Conconi test-retest were small with a low standard error of the mean. The reliability data between the Conconi test-retest showed low coefficients of variations (CV) and high intraclass correlation coefficients (ICC). The total errors for the Conconi test-retest are low for the measured variables (1.31 HR, 0.87 VO2, 0.65 SR, and 0.1 S). The Bland- Altman’s method for analysis validity showed a strong concordance according to the analyzed variables. We conclude that the modified Conconi test for on-water rowing is a valid and reliable method for the determination of the second ventilatory threshold (VT2). Key points The Modified Conconi test for on-water rowing is a simple and non-invasive method for the determination of anaerobic threshold for on-water rowing. The modified Conconi protocol for rowing was also shown to be a valid protocol for the calculation of the second ventilatory threshold using

  20. Tilting table for ergometer and for other biomedical devices

    NASA Technical Reports Server (NTRS)

    Gause, R. L.; Spier, R. A. (Inventor)

    1973-01-01

    The apparatus is for testing the human body in a variety of positions, ranging from the vertical to the supine, while exercising on an ergometer; and can also be used for angular positioning of other biomedical devices. It includes a floor plate and a hinged plate upon which to fix the ergometer, a back rest and a head rest attached at right angles to said hinged plate and behind the seat of the ergometer, dual hydraulic cylinders for raising and lowering the hinged plate through 90 deg by means of a self contained hydraulic system, with valve means for control and positive stops on the apparatus to prevent over travel. Tests can be made with the subject positioned on the seat of the ergometer, through the various angles, with a substantially normal body attitude relative to the seat and ergometer.

  1. Accuracy and Validity of Commercially Available Kayak Ergometers.

    PubMed

    Borges, Thiago Oliveira; Bullock, Nicola; Aitken, David; Coutts, Aaron J

    2017-02-09

    This study compared three commercially available ergometers for within- and between- brand difference to a first principles calibration rig. All ergometers underestimated true mean power with errors of 27.6 ± 3.7%, 4.5 ± 3.5% and 22.5 ± 1.9% for the KayakPro(®), WEBA and Dansprint. Within-brand ergometer power differences ranged from 17 ± 9 to 22 ± 11 W for the KayakPro(®); 3 ± 4 to 4 ±4 W for the WEBA and 5 ± 3 to 5 ± 4 W for the Dansprint. The linear regression analysis showed that most kayak ergometers possess a stable CV (0.9 - 1.7 %) with a Moderate ES. Taken collectively, these findings show that different ergometers present inconsistent outcomes. Therefore, we suggest that athlete testing should be conducted on the same ergometer brand and preferably the same ergometer. Optimally, that ergometer should be calibrated using a first principle device prior to any athlete testing block.

  2. Does Standing on a Cycle-ergometer, Towards the Conclusion of a Graded Exercise Test, Yield Cardiorespiratory Values Equivalent to Treadmill Testing?

    PubMed

    Mitchell, Joshua; Kist, William B; Mears, Kendall; Nalls, Jesse; Ritter, Kyle

    Graded exercise testing (GXT), per a cycle-ergometer (CE), offers safety and monitoring advantages over treadmill (TM) GXT. Unfortunately, CE-VO2max and some other cardiorespiratory (CR) variables are frequently lower than TM-GXT values. It has been difficult to compare TM and CE-GXT values. However, it was hypothesized that standing towards the conclusion of the CE-GXT (Stand-CE) might increase CE values to those equal to TM-GXT. If Stand-CE and TM-GXT CR values were equal, Stand-CE-GXT could become the method of choice for GXT for the general population. The purpose of this investigation was to investigate the effect of Stand-CE on CR variables. An intentionally diverse sample (N = 34, 24 males and 10 females, aged 18-54 y, with VO2max values 25-76 ml/kg/min) representing the "apparently healthy" general population participated. Volunteers completed two GXT trials, one per TM (Bruce protocol) and the other per a MET-TM-matched CE-GXT where initially seated participants stood and pedaled after their respiratory exchange ratio (RER) reached 1.0. Eighteen participants underwent a third MET-TM-matched trial where they remained seated throughout GXT (Sit-CE). Trials were counter-balanced with at least 48 h between GXT. There were significant statistical differences (p < 0.05) between TM and Stand-CE per matched-samples T-test (N = 34) on the following variables: VEmax (TM = 115 ± 24.4 l/min, Stand-CE = 99.4 ± 28.1), VCO2max (TM = 4.26 ± 0.9 l/min, Stand-CE = 3.56 ± 0.84), VO2max (TM = 44.9 ± 9.1 ml/kg/min, Stand-CE = 39.3 ± 9.0), METSmax (TM = 12.8 ± 2.6 METS, Stand-CE = 11.2 ± 2.5), and HRmax (TM = 175 ± 13 bpm, Stand-CE = 166 ± 12). One-way repeated measures ANOVA (N = 18) demonstrated no statistical differences among all trials: VEmax (TM = 112.8 ± 25.3 l/min, Stand-CE = 102.3 ± 25.2, Sit-CE = 107.3 ± 33.1), VCO2max (TM = 4.17 ± 0.99 l/min, Stand-CE = 3.62 ± 0.80, Sit-CE = 3.55 ± 0.83), VO2max (TM = 47.1 ± 9.8 ml/kg/min, Stand-CE = 42.0 ± 9.0, Sit

  3. Repeatability and Validity of the Combined Arm-Leg (Cruiser) Ergometer

    ERIC Educational Resources Information Center

    Simmelink, Elisabeth K.; Wempe, Johan B.; Geertzen, Jan H. B.; Dekker, Rienk

    2009-01-01

    The measurement of physical fitness of lower limb amputees is difficult, as the commonly used ergometer tests have limitations. A combined arm-leg (Cruiser) ergometer might be valuable. The aim of this study was to establish the repeatability and validity of the combined arm-leg (Cruiser) ergometer. Thirty healthy volunteers carried out three…

  4. Repeatability and Validity of the Combined Arm-Leg (Cruiser) Ergometer

    ERIC Educational Resources Information Center

    Simmelink, Elisabeth K.; Wempe, Johan B.; Geertzen, Jan H. B.; Dekker, Rienk

    2009-01-01

    The measurement of physical fitness of lower limb amputees is difficult, as the commonly used ergometer tests have limitations. A combined arm-leg (Cruiser) ergometer might be valuable. The aim of this study was to establish the repeatability and validity of the combined arm-leg (Cruiser) ergometer. Thirty healthy volunteers carried out three…

  5. Effects of the rotor pedalling system on the performance of trained cyclists during incremental and constant-load cycle-ergometer tests.

    PubMed

    Lucía, A; Balmer, J; Davison, R C R; Pérez, M; Santalla, A; Smith, P M

    2004-10-01

    The aim of this study was to determine the effects of Rotor, a new cycle crank configuration that effectively allows the pedals to move independently throughout the duty cycle, on indices of endurance cycling performance in trained cyclists. Ten cyclists (5 Rotor users and 5 non-users; age (mean +/- SD): 22 +/- 5 y; VO(2)max: 69.5 +/- 5.1 mL. kg(-1).min(-1)) volunteered to participate in the study. On four separate days, the subjects performed four cycle-ergometer tests, i.e. two incremental tests and two 20-min tests. An imposed crank rate of 75 rev.min(-1) was used during all tests. The incremental protocol started at 112.5 W, and the power output was increased by 37.5 W every 3 min until volitional exhaustion. The 20-min tests were performed at a fixed power output equivalent to 80 % of the highest power output that the cyclists maintained for a complete 3-min period during incremental tests. Both types of tests were performed with the conventional crank system and the Rotor following a counter-balanced, cross-over design. Gas exchange parameters were measured in all the tests and blood lactate was determined at the end of each 3-min period (incremental tests) and at the end of the 20-min tests. A three factor (pedalling system used during the tests x habitual pedalling system x power output [incremental tests] or time [20-min tests]) ANOVA with repeated measures on power output (incremental tests) or time (20-min tests) was used to analyse several indices of performance, e.g. peak power output, VO(2)max, lactate threshold, onset of blood lactate accumulation, economy, delta, and gross efficiency. No differences (p > 0.05) were found between the Rotor and conventional systems for any of the aforementioned variables. It seems that the theoretical advantage brought about by the Rotor system, i.e. improved contra-lateral cooperation of both legs, would be minimized in trained cyclists. Although field studies are needed to assess the possible implications, in terms

  6. Cross-Validation of the YMCA Submaximal Cycle Ergometer Test to Predict V[o.sub.2] Max

    ERIC Educational Resources Information Center

    Beekley, Matthew D.; Brechue, William F.; deHoyos, Diego V.; Garzarella, Linda; Werber-Zion, Galila; Pollock, Michael L.

    2004-01-01

    Maximal oxygen uptake (V[O.sub.2]max) is an important indicator of health-risk status, specifically for coronary heart disease (Blair et al., 1989). Direct measurement of V[O.sub.2]max is considered to be the most accurate means of determining cardiovascular fitness level. Typically, this measurement is taken using a progressive exercise test on a…

  7. Cross-Validation of the YMCA Submaximal Cycle Ergometer Test to Predict V[o.sub.2] Max

    ERIC Educational Resources Information Center

    Beekley, Matthew D.; Brechue, William F.; deHoyos, Diego V.; Garzarella, Linda; Werber-Zion, Galila; Pollock, Michael L.

    2004-01-01

    Maximal oxygen uptake (V[O.sub.2]max) is an important indicator of health-risk status, specifically for coronary heart disease (Blair et al., 1989). Direct measurement of V[O.sub.2]max is considered to be the most accurate means of determining cardiovascular fitness level. Typically, this measurement is taken using a progressive exercise test on a…

  8. Astronaut Charles Conrad following exercise session on bicycle ergometer

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Charles Conrad Jr., commander of the first manned Skylab mission, wipes perspiration from his face following an exercise session on the bicycle ergometer during Skylab training at JSC. Conrad is in the work and experiments compartment of the crew quarters of the Skylab Orbital Workshop (OWS) trainer at JSC. In addition to being the prime exercise for the crewmen, the ergometer is also used for the vector-cardiogram test and the metabolic activity experiment. The bicycle ergometer produces measured work loads for use in determining man's metabolic effectiveness.

  9. Repeatability and validity of the combined arm-leg (Cruiser) ergometer.

    PubMed

    Simmelink, Elisabeth K; Wempe, Johan B; Geertzen, Jan H B; Dekker, Rienk

    2009-12-01

    The measurement of physical fitness of lower limb amputees is difficult, as the commonly used ergometer tests have limitations. A combined arm-leg (Cruiser) ergometer might be valuable. The aim of this study was to establish the repeatability and validity of the combined arm-leg (Cruiser) ergometer. Thirty healthy volunteers carried out three incremental exercise tests, once on the bicycle ergometer and twice on the Cruiser ergometer. The repeatability of the Cruiser ergometer was assessed by studying the mean values of the test-retest and the validity by studying the mean values of the bicycle and the two Cruiser ergometer tests. The intraclass correlation coefficient for repeated measurements on the Cruiser ergometer was 0.84 for the maximal oxygen consumption (VO2max), and 0.71 for the maximal heart rate (HRmax). The intraclass correlation coefficient for the measurements on the bicycle ergometer and the Cruiser ergometer was 0.86 for the VO2max and 0.73 for HRmax. Bland and Altman plots for VO2max and HRmax showed a bias close to zero and a great accuracy. The conclusion of this study is that the Cruiser ergometer provides a repeatable and valid measurement of physical fitness in healthy volunteers. Its value in clinical practice for lower limb amputees needs to be further established.

  10. Applied physiology of rowing.

    PubMed

    Hagerman, F C

    1984-01-01

    Elite oarsmen and oarswomen possess large body dimensions and show outstanding aerobic and anaerobic qualities. Oarsmen have VO2max values of 6.1 +/- 0.6 L/min and have incurred O2 debts of between 10 and 20 litres. The caloric expenditure of rowing estimated from the O2 cost of a 6-minute rowing ergometer exercise was calculated at 36 kcal/min, one of the highest energy costs so far reported for any predominantly aerobic-type sport. Aerobic and anaerobic calculations show that 70 to 75% of the energy necessary to row the standard 2000m distance for men is derived from aerobiosis while the remaining 25 to 30% is anaerobic. Women achieve VO2max values of 4.1 +/- 0.4 L/min and slightly lower anaerobic values than men. The relative 60 to 65% energy contribution of aerobic metabolism and 35 to 40% for anaerobiosis is not surprising since women compete at 1000m. Rowers also exhibit excellent isokinetic leg strength and power when compared with other elite athletes and oarswomen produced higher relative leg strength values than men when lean body mass is considered. Muscle fibre type distributions in oarsmen resemble those of distance runners while women tend to have a slightly higher proportion of fast-twitch fibres. An average power output of 390 +/- 13.6W was produced by oarsmen for 6 minutes of simulated rowing while women were able to develop 300 +/- 18.4 for 3 minutes of the same activity. Mechanical efficiency for rowing was calculated at 20 +/- 0.9%. Oarsmen also achieve very high ventilation volumes being able to average above 200 L/min BTPS for 6 minutes of simulated rowing; women ventilate 170 L/min BTPS for 3 minutes of this exercise. Excellent VO2/VE and O2 pulse values demonstrate outstanding cardiorespiratory efficiency. Both oarsmen and oarswomen utilise a unique physiological pattern of race pacing; they begin exertion with a vigorous sprint which places excessive demands on anaerobic metabolism followed by a severely high aerobic steady-state and then

  11. Testing functional and morphological interpretations of enamel thickness along the deciduous tooth row in human children.

    PubMed

    Mahoney, Patrick

    2013-08-01

    The significance of a gradient in enamel thickness along the human permanent molar row has been debated in the literature. Some attribute increased enamel thickness from first to third molars to greater bite force during chewing. Others argue that thicker third molar enamel relates to a smaller crown size facilitated by a reduced dentin component. Thus, differences in morphology, not function, explains enamel thickness. This study draws on these different interpretive models to assess enamel thickness along the entire human deciduous tooth row. Average enamel thickness (AET), the area and proportion of crown enamel and dentin, and a crown size proxy are calculated for incisors, canines, and molars. Allometric scaling relationships are assessed within each tooth class, and then comparisons are undertaken along the row. Generally, AET was correlated with crown size and scaled with isometry, except for second molars which scaled with positive allometry. Mean AET increased along the row and was greater on molars, where bite forces are reported to be higher. Second molars combined the largest crown size with the thickest enamel and the smallest proportion of dentin, which is consistent with a reduction in the potential for cusp fracture under high bite forces. Resistance to wear may also account for some enamel thickness variation between tooth classes. Dental reduction did not explain the trend in AET from central to lateral incisors, or from first to second molars. The gradient in AET along the deciduous tooth row is partly consistent with a functional interpretation of enamel thickness.

  12. Rowing Physiology.

    ERIC Educational Resources Information Center

    Spinks, W. L.

    This review of the literature discusses and examines the methods used in physiological assessment of rowers, results of such assessments, and future directions emanating from research in the physiology of rowing. The first section discusses the energy demands of rowing, including the contribution of the energy system, anaerobic metabolism, and the…

  13. Soil heat flux calculation for sunlit and shaded surfaces under row crops: 2. Model Test

    USDA-ARS?s Scientific Manuscript database

    A method to calculate surface soil heat flux (G0) as a function of net radiation to the soil (RN,S) was developed that accounts for positional variability across a row crop interrow. The method divides the interrow into separate sections, which may be shaded, partially sunlit, or fully sunlit, and c...

  14. Effect of sodium bicarbonate supplementation on 2000-m rowing performance.

    PubMed

    Hobson, Ruth M; Harris, Roger C; Martin, Dan; Smith, Perry; Macklin, Ben; Elliott-Sale, Kirsty J; Sale, Craig

    2014-01-01

    The ability to buffer H+ could be vital to exercise performance, as high concentrations of H+ contribute to the development of fatigue. The authors examined the effect of sodium bicarbonate (SB) supplementation on 2000-m rowing-ergometer performance. Twenty male rowers (age 23 ± 4 y, height 1.85 ± 0.08 m, mass 82.5 ± 8.9 kg, 2000-m personal-best time 409 ± 16 s) completed two 2000-m rowing-ergometer time trials, separated by 48 h. Participants were supplemented before exercise with 0.3 g/kg body mass of SB or a placebo (maltodextrin; PLA). The trials were conducted using a double-blinded, randomized, counterbalanced crossover study design. Time to complete the 2000-m and time taken for each 500-m split were recorded. Blood lactate, bicarbonate, pH, and base excess were determined preexercise, immediately postexercise, and 5 min postexercise. Performance data were analyzed using paired t tests, as well as magnitude-based inferences; hematological data were analyzed using a repeated-measures ANOVA. Using paired t tests, there was no benefit of SB over PLA (P = .095). However, using magnitude-based inferences there was a likely beneficial effect of SB compared with PLA (PLA 412.0 ± 15.1 s, SB 410.7 ± 14.9 s). Furthermore, SB was 0.5 ± 1.2 s faster than PLA in the third 500 m (P = .035; possibly beneficial) and 1.1 ± 1.7 s faster in the fourth 500 m (P = .004; very likely beneficial). All hematological data were different between SB and PLA and were different from preexercise to postexercise. SB supplementation is likely to be beneficial to the performance of those competing in 2000-m rowing events, particularly in the second half of the event.

  15. Cooling Tests of a Single-Row Radial Engine with Several NACA Cowlings

    NASA Technical Reports Server (NTRS)

    Brevoort, M J; Stickle, George W; Ellerbrock, Herman H , Jr

    1937-01-01

    The cooling of a single-row radial air-cooled engine using several cowling arrangements has been studied in the NACA 20-foot wind tunnel. The results show the effect of the propeller and several cowling arrangements on cooling for various values of the indicated horsepower in the climb condition. A table giving comparative performance of the various cowling arrangements is presented. The dependence of temperature on indicated horsepower and pressure drop across the baffles is shown by charts. Other charts show the limiting indicated horsepower against the pressure drop across the engine and the heat dissipated at various values of the indicated horsepower.

  16. Louisiana farm discussion: 8 foot row spacing

    USDA-ARS?s Scientific Manuscript database

    This year several tests in growers’ fields were used to compare traditional 6-foot row spacing to 8-foot row spacing. Cane is double-drilled in the wider row spacing. The wider row spacing would accommodate John Deere 3522 harvester. Field data indicate the sugarcane yields are very comparable in 8-...

  17. Rowing injuries.

    PubMed

    Rumball, Jane S; Lebrun, Constance M; Di Ciacca, Stephen R; Orlando, Karen

    2005-01-01

    Participation in the sport of rowing has been steadily increasing in recent decades, yet few studies address the specific injuries incurred. This article reviews the most common injuries described in the literature, including musculoskeletal problems in the lower back, ribs, shoulder, wrist and knee. A review of basic rowing physiology and equipment is included, along with a description of the mechanics of the rowing stroke. This information is necessary in order to make an accurate diagnosis and treatment protocol for these injuries, which are mainly chronic in nature. The most frequently injured region is the low back, mainly due to excessive hyperflexion and twisting, and can include specific injuries such as spondylolysis, sacroiliac joint dysfunction and disc herniation. Rib stress fractures account for the most time lost from on-water training and competition. Although theories abound for the mechanism of injury, the exact aetiology of rib stress fractures remains unknown. Other injuries discussed within, which are specific to ribs, include costochondritis, costovertebral joint subluxation and intercostal muscle strains. Shoulder pain is quite common in rowers and can be the result of overuse, poor technique, or tension in the upper body. Injuries concerning the forearm and wrist are also common, and can include exertional compartment syndrome, lateral epicondylitis, deQuervain's and intersection syndrome, and tenosynovitis of the wrist extensors. In the lower body, the major injuries reported include generalised patellofemoral pain due to abnormal patellar tracking, and iliotibial band friction syndrome. Lastly, dermatological issues, such as blisters and abrasions, and miscellaneous issues, such as environmental concerns and the female athlete triad, are also included in this article.Pathophysiology, mechanism of injury, assessment and management strategies are outlined in the text for each injury, with special attention given to ways to correct

  18. Rowing Crew Coordination Dynamics at Increasing Stroke Rates

    PubMed Central

    2015-01-01

    In rowing, perfect synchronisation is important for optimal performance of a crew. Remarkably, a recent study on ergometers demonstrated that antiphase crew coordination might be mechanically more efficient by reducing the power lost to within-cycle velocity fluctuations of the boat. However, coupled oscillator dynamics predict the stability of the coordination to decrease with increasing stroke rate, which in case of antiphase may eventually yield breakdowns to in-phase. Therefore, this study examined the effects of increasing stroke rate on in- and antiphase crew coordination in rowing dyads. Eleven experienced dyads rowed on two mechanically coupled ergometers on slides, which allowed the ergometer system to move back and forth as one ‘boat’. The dyads performed a ramp trial in both in- and antiphase pattern, in which stroke rates gradually increased from 30 strokes per minute (spm) to as fast as possible in steps of 2 spm. Kinematics of rowers, handles and ergometers were captured. Two dyads showed a breakdown of antiphase into in-phase coordination at the first stroke rate of the ramp trial. The other nine dyads reached between 34–42 spm in antiphase but achieved higher rates in in-phase. As expected, the coordinative accuracy in antiphase was worse than in in-phase crew coordination, while, somewhat surprisingly, the coordinative variability did not differ between the patterns. Whereas crew coordination did not substantially deteriorate with increasing stroke rate, stroke rate did affect the velocity fluctuations of the ergometers: fluctuations were clearly larger in the in-phase pattern than in the antiphase pattern, and this difference significantly increased with stroke rate. Together, these results suggest that although antiphase rowing is less stable (i.e., less resistant to perturbation), potential on-water benefits of antiphase over in-phase rowing may actually increase with stroke rate. PMID:26185987

  19. Gross efficiency and cycling economy are higher in the field as compared with on an Axiom stationary ergometer.

    PubMed

    Bertucci, William M; Betik, Andrew C; Duc, Sebastien; Grappe, Frederic

    2012-12-01

    This study was designed to examine the biomechanical and physiological responses between cycling on the Axiom stationary ergometer (Axiom, Elite, Fontaniva, Italy) vs. field conditions for both uphill and level ground cycling. Nine cyclists performed cycling bouts in the laboratory on an Axiom stationary ergometer and on their personal road bikes in actual road cycling conditions in the field with three pedaling cadences during uphill and level cycling. Gross efficiency and cycling economy were lower (-10%) for the Axiom stationary ergometer compared with the field. The preferred pedaling cadence was higher for the Axiom stationary ergometer conditions compared with the field conditions only for uphill cycling. Our data suggests that simulated cycling using the Axiom stationary ergometer differs from actual cycling in the field. These results should be taken into account notably for improving the precision of the model of cycling performance, and when it is necessary to compare two cycling test conditions (field/laboratory, using different ergometers).

  20. Astronaut Charles Conrad using the bicycle ergometer

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Charles Conrad Jr., Skylab 2 commander, during an exercise session on the bicycle ergometer in the crew quarters of the Skylab Orbital Workshop (OWS) in the Skylab 2 space station cluster in Earth orbit.

  1. Astronaut Charles Conrad using the bicycle ergometer

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Charles Conrad Jr., Skylab 2 commander, during an exercise session on the bicycle ergometer in the crew quarters of the Skylab Orbital Workshop (OWS) in the Skylab 2 space station cluster in Earth orbit.

  2. Wakata on Cycle Ergometer in Lab

    NASA Image and Video Library

    2009-05-30

    ISS020-E-005790 (30 May 2009) --- Japan Aerospace Exploration Agency (JAXA) astronaut Koichi Wakata, Expedition 20 flight engineer, exercises on the Cycle Ergometer with Vibration Isolation System (CEVIS) in the Destiny laboratory of the International Space Station.

  3. Effects of kayak ergometer training on motor performance in paraplegics.

    PubMed

    Bjerkefors, A; Thorstensson, A

    2006-10-01

    The purpose of this study was to assess the effects of kayak ergometer training on functional tests performed in wheelchair by persons with spinal cord injury. Ten post-rehabilitated persons with thoracic spinal cord injury volunteered for the study and performed 30 sessions of kayak ergometer training during a 10-week period. The ergometer was modified with an additional balance demand in the medio-lateral direction. Before and after the training period the subjects performed functional tests in the wheelchair: Sit-and-reach tests (distance), mounting a platform, transfer to a bench (height), propelling the wheelchair: 5 m on the rear wheels; in a figure-8; 15 m on a level surface and 50 m on a 3 degrees inclined surface (time). Test-retests were performed for all tests before the training began. A written questionnaire was distributed to evaluate the subjective experiences of the training. The test-retest resulted in coefficient of variation of 1.3 - 4.6 %. There were significant improvements in sit-and-reach (14 %), mounting a platform (7 %), transfer to a bench (10 %), propelling on level (3 %), and inclined surface (6 %). Furthermore, the training, did not cause any shoulder pain or other problems. This, and the positive subjective experience expressed by the subjects after the training indicate that this type of training is a suitable activity for persons with thoracic spinal cord injury.

  4. Test/QA plan for the validation of the verification protocol for low speed pesticide spray drift reduction technologies for row and field crops

    EPA Science Inventory

    This test/QA plan for evaluation the generic test protocol for high speed wind tunnel, representing aerial application, pesticide spray drift reduction technologies (DRT) for row and field crops is in conformance with EPA Requirements for Quality Assurance Project Plans (EPA QA/R...

  5. Test/QA plan for the validation of the verification protocol for high speed pesticide spray drift reduction technologies for row and field crops

    EPA Science Inventory

    This test/QA plan for evaluation the generic test protocol for high speed wind tunnel, representing aerial application, pesticide spray drift reduction technologies (DRT) for row and field crops is in conformance with EPA Requirements for Quality Assurance Project Plans (EPA QA/R...

  6. Test/QA plan for the validation of the verification protocol for low speed pesticide spray drift reduction technologies for row and field crops

    EPA Science Inventory

    This test/QA plan for evaluation the generic test protocol for high speed wind tunnel, representing aerial application, pesticide spray drift reduction technologies (DRT) for row and field crops is in conformance with EPA Requirements for Quality Assurance Project Plans (EPA QA/R...

  7. Test/QA plan for the validation of the verification protocol for high speed pesticide spray drift reduction technologies for row and field crops

    EPA Science Inventory

    This test/QA plan for evaluation the generic test protocol for high speed wind tunnel, representing aerial application, pesticide spray drift reduction technologies (DRT) for row and field crops is in conformance with EPA Requirements for Quality Assurance Project Plans (EPA QA/R...

  8. Comparison of the US and Russian Cycle Ergometers

    NASA Technical Reports Server (NTRS)

    Norcross, Jason; Bentley, Jason R.; Moore, Alan D.; Hagan, R. Donald

    2007-01-01

    The purpose of this study was to compare the U.S. and Russian cycle ergometers focusing on the mechanical differences of the devices and the physiological differences observed while using the devices. Methods: First, the mechanical loads provided by the U.S. Cycle Ergometer with Vibration Isolation System (CEVIS) and the Russian Veloergometer were measured using a calibration dynamometer. Results were compared and conversion equations were modeled to determine the actual load provided by each device. Second, ten male subjects (32.9 +/- 6.5 yrs, 180.6 +/- 4.4 cm; 81.9 +/- 6.9 kg) experienced with both cycling and exercise testing completed a standardized submaximal exercise test protocol on CEVIS and Veloergometer. The exercise protocol involved 8 sub-maximal workloads each lasting 3 minutes for a total of 24 minutes per session, or until the end of the stage when the subject reached 85% of peak oxygen consumption or age-predicted maximum heart rate (220 - age). The workload started at 50 Watts (W), increased to 100 W, and then increased 25 W every 3 minutes until reaching a peak workload of 250 W. Physiological variables were then compared at each workload by repeated measures ANOVA or paired t-tests (p<0.05). Results: While both CEVIS and Veloergometer produced significantly lower workloads than the displayed workload, CEVIS produced even lower loads than Veloergometer (p<0.05) at each indicated workload. Despite this fact, the only physiological variables that showed a significant difference between the ergometers were VE (125 - 250W), VO2 (175 and 250 W), and VCO2 (175 W). All other physiological data were not statistically different between CEVIS and Veloergometer. Conclusion: Although workloads were different between ergometers, relatively few physiological differences were observed. Therefore, CEVIS workloads of 87.5 - 262.5 W can be rounded to the nearest 25 W increment and performed on the Veloergometer.

  9. Generic Verification Protocol for Testing Pesticide Application Spray Drift Reduction Technologies for Row and Field Crops

    EPA Pesticide Factsheets

    This generic verification protocol provides a detailed method to conduct and report results from a verification test of pesticide application technologies that can be used to evaluate these technologies for their potential to reduce spray drift.

  10. Dose response of caffeine on 2000-m rowing performance.

    PubMed

    Skinner, Tina L; Jenkins, David G; Coombes, Jeff S; Taaffe, Dennis R; Leveritt, Michael D

    2010-03-01

    To determine whether a dose-response relationship exists between caffeine and 2000-m rowing performance. In this randomized, placebo-controlled, double-blind crossover study, 10 competitive male rowers (mean +/- SD: age = 20.6 +/- 1.4 yr, body mass = 87.7 +/- 10.5 kg, height = 186.8 +/- 6.8 cm, (.)VO2peak = 5.1 +/- 0.6 L x min(-1)) consumed 2, 4, or 6 mg x kg(-1) caffeine or a placebo 60 min before completing a 2000-m time trial on a rowing ergometer. The trials were preceded by a 24-h standardized diet (including a light preexercise meal of 2 g x kg(-1) CHO), and subjects were tested preexercise for hydration, caffeine abstinence, and blood glucose concentrations. Time trial performance was not significantly different across the three caffeine doses or placebo (P = 0.249). After the three caffeine trials, postexercise plasma glucose and lactate concentrations were higher compared with the placebo trial (P < 0.05). Plasma caffeine concentrations after 60 min of ingestion were lower than the values reported previously by others following the same dose, and there was considerable interindividual variation in plasma caffeine concentrations in response to the various caffeine doses. The large interindividual response to the caffeine doses suggests that individual characteristics need to be considered when administering caffeine for performance enhancement. In addition, preexercise feeding may significantly affect plasma caffeine concentrations and the potential for caffeine to improve performance.

  11. Influence of foot-stretcher height on rowing technique and performance.

    PubMed

    Buckeridge, Erica M; Weinert-Aplin, Robert A; Bull, Anthony M J; McGregor, Alison H

    2016-11-01

    Strength, technique, and coordination are crucial to rowing performance, but external interventions such as foot-stretcher set-up can fine-tune technique and optimise power output. For the same resultant force, raising the height of foot-stretchers on a rowing ergometer theoretically alters the orientation of the resultant force vector in favour of the horizontal component. This study modified foot-stretcher heights and examined their instantaneous effect on foot forces and rowing technique. Ten male participants rowed at four foot-stretcher heights on an ergometer that measured handle force, stroke length, and vertical and horizontal foot forces. Rowers were instrumented with motion sensors to measure ankle, knee, hip, and lumbar-pelvic kinematics. Key resultant effects of increased foot-stretcher heights included progressive reductions in horizontal foot force, stroke length, and pelvis range of motion. Raising foot-stretcher height did not increase the horizontal component of foot force as previously speculated. The reduced ability to anteriorly rotate the pelvis at the front of the stroke may be a key obstacle in gaining benefits from raised foot-stretcher heights. This study shows that small changes in athlete set-up can influence ergometer rowing technique, and rowers must individually fine-tune their foot-stretcher height to optimise power transfer through the rowing stroke on an ergometer.

  12. Billet planting, 8-foot rows, residue updates

    USDA-ARS?s Scientific Manuscript database

    Cultural practices are continually tested and upgraded to maximize sugarcane yield in Louisiana. Over the past 3 years extensive research went in to comparing the industry standard 6-foot row spacing to a wider, 8 foot row. Each 8 foot row was double drilled with seed canes that were 2-3 feet apart....

  13. Investigating the Effects of Typical Rowing Strength Training Practices on Strength and Power Development and 2,000 m Rowing Performance.

    PubMed

    Ian Gee, Thomas; Caplan, Nicholas; Christian Gibbon, Karl; Howatson, Glyn; Grant Thompson, Kevin

    2016-04-01

    This study aimed to determine the effects of a short-term, strength training intervention, typically undertaken by club-standard rowers, on 2,000 m rowing performance and strength and power development. Twenty-eight male rowers were randomly assigned to intervention or control groups. All participants performed baseline testing involving assessments of muscle soreness, creatine kinase activity (CK), maximal voluntary contraction (leg-extensors) (MVC), static-squat jumps (SSJ), counter-movement jumps (CMJ), maximal rowing power strokes (PS) and a 2,000 m rowing ergometer time-trial (2,000 m) with accompanying respiratory-exchange and electromyography (EMG) analysis. Intervention group participants subsequently performed three identical strength training (ST) sessions, in the space of five days, repeating all assessments 24 h following the final ST. The control group completed the same testing procedure but with no ST. Following ST, the intervention group experienced significant elevations in soreness and CK activity, and decrements in MVC, SSJ, CMJ and PS (p < 0.01). However, 2,000 m rowing performance, pacing strategy and gas exchange were unchanged across trials in either condition. Following ST, significant increases occurred for EMG (p < 0.05), and there were non-significant trends for decreased blood lactate and anaerobic energy liberation (p = 0.063 - 0.086). In summary, club-standard rowers, following an intensive period of strength training, maintained their 2,000 m rowing performance despite suffering symptoms of muscle damage and disruption to muscle function. This disruption likely reflected the presence of acute residual fatigue, potentially in type II muscle fibres as strength and power development were affected.

  14. Investigating the Effects of Typical Rowing Strength Training Practices on Strength and Power Development and 2,000 m Rowing Performance

    PubMed Central

    Caplan, Nicholas; Christian Gibbon, Karl; Howatson, Glyn; Grant Thompson, Kevin

    2016-01-01

    Abstract This study aimed to determine the effects of a short-term, strength training intervention, typically undertaken by club-standard rowers, on 2,000 m rowing performance and strength and power development. Twenty-eight male rowers were randomly assigned to intervention or control groups. All participants performed baseline testing involving assessments of muscle soreness, creatine kinase activity (CK), maximal voluntary contraction (leg-extensors) (MVC), static-squat jumps (SSJ), counter-movement jumps (CMJ), maximal rowing power strokes (PS) and a 2,000 m rowing ergometer time-trial (2,000 m) with accompanying respiratory-exchange and electromyography (EMG) analysis. Intervention group participants subsequently performed three identical strength training (ST) sessions, in the space of five days, repeating all assessments 24 h following the final ST. The control group completed the same testing procedure but with no ST. Following ST, the intervention group experienced significant elevations in soreness and CK activity, and decrements in MVC, SSJ, CMJ and PS (p < 0.01). However, 2,000 m rowing performance, pacing strategy and gas exchange were unchanged across trials in either condition. Following ST, significant increases occurred for EMG (p < 0.05), and there were non-significant trends for decreased blood lactate and anaerobic energy liberation (p = 0.063 – 0.086). In summary, club-standard rowers, following an intensive period of strength training, maintained their 2,000 m rowing performance despite suffering symptoms of muscle damage and disruption to muscle function. This disruption likely reflected the presence of acute residual fatigue, potentially in type II muscle fibres as strength and power development were affected. PMID:28149354

  15. Don't rock the boat: how antiphase crew coordination affects rowing.

    PubMed

    de Brouwer, Anouk J; de Poel, Harjo J; Hofmijster, Mathijs J

    2013-01-01

    It is generally accepted that crew rowing requires perfect synchronization between the movements of the rowers. However, a long-standing and somewhat counterintuitive idea is that out-of-phase crew rowing might have benefits over in-phase (i.e., synchronous) rowing. In synchronous rowing, 5 to 6% of the power produced by the rower(s) is lost to velocity fluctuations of the shell within each rowing cycle. Theoretically, a possible way for crews to increase average boat velocity is to reduce these fluctuations by rowing in antiphase coordination, a strategy in which rowers perfectly alternate their movements. On the other hand, the framework of coordination dynamics explicates that antiphase coordination is less stable than in-phase coordination, which may impede performance gains. Therefore, we compared antiphase to in-phase crew rowing performance in an ergometer experiment. Nine pairs of rowers performed a two-minute maximum effort in-phase and antiphase trial at 36 strokes min(-1) on two coupled free-floating ergometers that allowed for power losses to velocity fluctuations. Rower and ergometer kinetics and kinematics were measured during the trials. All nine pairs easily acquired antiphase rowing during the warm-up, while one pair's coordination briefly switched to in-phase during the maximum effort trial. Although antiphase interpersonal coordination was indeed less accurate and more variable, power production was not negatively affected. Importantly, in antiphase rowing the decreased power loss to velocity fluctuations resulted in more useful power being transferred to the ergometer flywheels. These results imply that antiphase rowing may indeed improve performance, even without any experience with antiphase technique. Furthermore, it demonstrates that although perfectly synchronous coordination may be the most stable, it is not necessarily equated with the most efficient or optimal performance.

  16. Don’t Rock the Boat: How Antiphase Crew Coordination Affects Rowing

    PubMed Central

    de Brouwer, Anouk J.; de Poel, Harjo J.; Hofmijster, Mathijs J.

    2013-01-01

    It is generally accepted that crew rowing requires perfect synchronization between the movements of the rowers. However, a long-standing and somewhat counterintuitive idea is that out-of-phase crew rowing might have benefits over in-phase (i.e., synchronous) rowing. In synchronous rowing, 5 to 6% of the power produced by the rower(s) is lost to velocity fluctuations of the shell within each rowing cycle. Theoretically, a possible way for crews to increase average boat velocity is to reduce these fluctuations by rowing in antiphase coordination, a strategy in which rowers perfectly alternate their movements. On the other hand, the framework of coordination dynamics explicates that antiphase coordination is less stable than in-phase coordination, which may impede performance gains. Therefore, we compared antiphase to in-phase crew rowing performance in an ergometer experiment. Nine pairs of rowers performed a two-minute maximum effort in-phase and antiphase trial at 36 strokes min−1 on two coupled free-floating ergometers that allowed for power losses to velocity fluctuations. Rower and ergometer kinetics and kinematics were measured during the trials. All nine pairs easily acquired antiphase rowing during the warm-up, while one pair’s coordination briefly switched to in-phase during the maximum effort trial. Although antiphase interpersonal coordination was indeed less accurate and more variable, power production was not negatively affected. Importantly, in antiphase rowing the decreased power loss to velocity fluctuations resulted in more useful power being transferred to the ergometer flywheels. These results imply that antiphase rowing may indeed improve performance, even without any experience with antiphase technique. Furthermore, it demonstrates that although perfectly synchronous coordination may be the most stable, it is not necessarily equated with the most efficient or optimal performance. PMID:23383024

  17. Voss in Service module with cycle ergometer

    NASA Image and Video Library

    2001-03-23

    ISS002-E-5734 (23 March 2001) --- Astronaut James S. Voss, Expedition Two flight engineer, gives his arms and upper body a workout with the bicycle ergometer facility in the Zvezda Service Module aboard the International Space Station (ISS). The image was recorded with a digital still camera.

  18. Glenn exercises on ergometer while on middeck

    NASA Image and Video Library

    1998-11-04

    STS095-E-5251 (4 Nov. 1998) --- U.S. Sen. John H. Glenn Jr. (D.-Ohio), STS-95 payload specialist, works out on the ergometer device onboard Discovery. The photograph was taken with an electronic still camera (ESC) at 21:52:07 GMT, Nov. 4.

  19. REMOTE, a Wireless Sensor Network Based System to Monitor Rowing Performance

    PubMed Central

    Llosa, Jordi; Vilajosana, Ignasi; Vilajosana, Xavier; Navarro, Nacho; Suriñach, Emma; Marquès, Joan Manuel

    2009-01-01

    In this paper, we take a hard look at the performance of REMOTE, a sensor network based application that provides a detailed picture of a boat movement, individual rower performance, or his/her performance compared with other crew members. The application analyzes data gathered with a WSN strategically deployed over a boat to obtain information on the boat and oar movements. Functionalities of REMOTE are compared to those of RowX [1] outdoor instrument, a commercial wired sensor instrument designed for similar purposes. This study demonstrates that with smart geometrical configuration of the sensors, rotation and translation of the oars and boat can be obtained. Three different tests are performed: laboratory calibration allows us to become familiar with the accelerometer readings and validate the theory, ergometer tests which help us to set the acquisition parameters, and on boat tests shows the application potential of this technologies in sports. PMID:22423204

  20. Reliability and validity of a new double poling ergometer for cross-country skiers.

    PubMed

    Holmberg, Hans-Christer; Nilsson, Johnny

    2008-01-15

    Thirty-eight competitive cross-country skiers were divided into three groups to assess the reliability and validity of a new double poling ergometer. Group A (n = 22) performed two maximal 60-s tests, Group B (n = 8) repeated peak oxygen uptake tests on the double poling ergometer, and Group C (n = 8) performed a maximal 6-min test on the double poling ergometer and a double poling time-trial on snow. The correlation between the power calculated at the flywheel and the power applied at the base of the poles was r = 0.99 (P < 0.05). The power at the poles was 50-70% higher than that at the flywheel. There was a high test-retest reliability in the two 60-s power output tests (coefficient of variation = 3.0%) and no significant difference in peak oxygen uptake in the two 6-min all-out tests (coefficient of variation = 2.4%). There was a strong correlation between the absolute (W) and relative power (W x kg(-1)) output in the 6-min double poling ergometer test and the double poling performance on snow (r = 0.86 and 0.89 respectively; both P < 0.05). In conclusion, our results show that the double poling ergometer has both high reliability and validity. However, the power calculated at the flywheel underestimated the total power produced and needs to be corrected for in ergonomic estimations.

  1. Astronaut Richard Covey with control box for bicycle ergometer

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Astronaut Richard O. Covey, mission commander, is seen with the control box for bicycle ergometer on Endeavour. During the eleven-day STS-61 mission, crew members not performing spacewalks found the ergometer to provide much needed exercise.

  2. Responses to kayak ergometer performance after kayak and bicycle ergometer training.

    PubMed

    Ridge, B R; Pyke, F S; Roberts, A D

    1976-01-01

    Ten moderately active male volunteers, age 19-30 years, completed one month of training on either a kayak or a bicycle ergometer (five men in each group). The men completed sixteen 30 minute sessions of continuous work at an intensity which maintained their HR within 85-90% of its maximum, as previously determined on the kayak ergometer. After this training period the kayak group demonstrated significant decreases in VO2, VE, HR and blood lactate in submaximal kayak ergometer work and a significant increase in VO2 during maximal kayak ergometer work. These changes contributed to a significantly higher maximal kayaking work output. The bicycle-trained group did not make any of these improvements on the kayak ergometer. However in their last training session on the bicycle ergometer they were able to work at a higher submaximal load while maintaining the same heart rate as in the first training session. It was concluded that the circulatory and metabolic adjustments to kayak work are greater with kayak training than with bicycle training.

  3. Development and validation of an automated step ergometer.

    PubMed

    de Sousa, Maria do Socorro C; Aniceto, Rodrigo R; Neto, Gabriel R; de Araújo, Ravi C T; de Sousa, Juliana B C; Costa, José A D; Pellegrinotti, Idico L

    2014-09-29

    Laboratory ergometers have high costs, becoming inaccessible for most of the population, hence, it is imperative to develop affordable devices making evaluations like cardiorespiratory fitness feasible and easier. The objective of this study was to develop and validate an Automated Step Ergometer (ASE), adjusted according to the height of the subject, for predicting VO2max through a progressive test. The development process was comprised by three steps, the theoretical part, the prototype assembly and further validation. The ASE consists in an elevating platform that makes the step at a higher or lower level as required for testing. The ASE validation was obtained by comparing the values of predicted VO2max (equation) and direct gas analysis on the prototype and on a, treadmill. For the validation process 167 subjects with average age of 31.24 ± 14.38 years, of both genders and different degrees of cardiorespiratory fitness, were randomized and divided by gender and training condition, into untrained (n=106), active (n=24) and trained (n=37) subjects. Each participant performed a progressive test on which the ASE started at the same height (20 cm) for all. Then, according to the subject's height, it varied to a maximum of 45 cm. Time in each stage and rhythm was chosen in accordance with training condition from lowest to highest (60-180 s; 116-160 bpm, respectively). Data was compared with the student's t test and ANOVA; correlations were tested with Pearson's r. The value of α was set at 0.05. No differences were found between the predicted VO2max and the direct gas analysis VO2max, nor between the ASE and treadmill VO2max (p= 0.365) with high correlation between ergometers (r= 0.974). The values for repeatability, reproducibility, and reliability of male and female groups measures were, respectively, 4.08 and 5.02; 0.50 and 1.11; 4.11 and 5.15. The values of internal consistency (Cronbach's alpha) among measures were all >0.90. It was verified that the ASE

  4. Development and Validation of an Automated Step Ergometer

    PubMed Central

    de Sousa, Maria do Socorro C.; Aniceto, Rodrigo R.; Neto, Gabriel R.; de Araújo, Ravi C. T.; de Sousa, Juliana B. C.; Costa, José A. D.; Pellegrinotti, Idico L.

    2014-01-01

    Laboratory ergometers have high costs, becoming inaccessible for most of the population, hence, it is imperative to develop affordable devices making evaluations like cardiorespiratory fitness feasible and easier. The objective of this study was to develop and validate an Automated Step Ergometer (ASE), adjusted according to the height of the subject, for predicting VO2max through a progressive test. The development process was comprised by three steps, the theoretical part, the prototype assembly and further validation. The ASE consists in an elevating platform that makes the step at a higher or lower level as required for testing. The ASE validation was obtained by comparing the values of predicted VO2max (equation) and direct gas analysis on the prototype and on a, treadmill. For the validation process 167 subjects with average age of 31.24 ± 14.38 years, of both genders and different degrees of cardiorespiratory fitness, were randomized and divided by gender and training condition, into untrained (n=106), active (n=24) and trained (n=37) subjects. Each participant performed a progressive test on which the ASE started at the same height (20 cm) for all. Then, according to the subject’s height, it varied to a maximum of 45 cm. Time in each stage and rhythm was chosen in accordance with training condition from lowest to highest (60–180 s; 116–160 bpm, respectively). Data was compared with the student’s t test and ANOVA; correlations were tested with Pearson’s r. The value of α was set at 0.05. No differences were found between the predicted VO2max and the direct gas analysis VO2max, nor between the ASE and treadmill VO2max (p= 0.365) with high correlation between ergometers (r= 0.974). The values for repeatability, reproducibility, and reliability of male and female groups measures were, respectively, 4.08 and 5.02; 0.50 and 1.11; 4.11 and 5.15. The values of internal consistency (Cronbach’s alpha) among measures were all >0.90. It was verified that

  5. Comparison of treadmill and cycle ergometer measurements of force-velocity relationships and power output.

    PubMed

    Jaskólska, A; Goossens, P; Veenstra, B; Jaskólski, A; Skinner, J S

    1999-04-01

    Since body balance and weight-bearing factors present while running on the treadmill might cause additional muscle recruitment and thus could influence the force-velocity relationship and power, the present study was undertaken to find out whether the F-V and F-P relationships measured while running on the treadmill are different from the respective indices measured during cycling. On two separate occasions, 32 male subjects were tested using a series of 5 sec, all-out sprints against different braking forces on the Gymrol Sprint treadmill and on the Monark ergometer. The maximal peak power (PPmax) and maximal mean power (MPmax) were measured. The equation: EP = 0.5 maximal force (Fo) x0.5 maximal velocity (Vo) was used to calculate the estimated values of peak power (EPP) and mean power (EMP). The F-V relationship was linear in both cycle ergometer and treadmill measurements. PPmax, MPmax, EPP, and EMP values on the treadmill were lower than the respective values on the ergometer. EPP on the ergometer and on the treadmill, as well as EMP values on the ergometer, were slightly higher than the corresponding measured values of PPmax and MPmax. The levels of braking force at which PP, MP, PPmax, and MPmax were obtained were lower on the ergometer than on the treadmill. High correlation coefficients were found between PPmax, MPmax, EPP, and EMP measured on the ergometer and on the treadmill (r = 0.86, r = 0.84, r = 0.71, r = 0.78, respectively, P<0.01). In both tests, significant relationships between PPmax, MPmax, EPP, and EMP were observed. It is concluded that independent of the type of ergometry the force-velocity relationship is similar in the measured range of velocities which suggests that the number of muscle groups and joints engaged in movement are more important than body balance and weight-bearing factors present while running on a treadmill.

  6. Magnetic force microscopy and spinstand testing of multi-row-per-track discrete bit patterned media fabricated by focused ion beam

    NASA Astrophysics Data System (ADS)

    Chen, Y. J.; Huang, T. L.; Leong, S. H.; Hu, S. B.; Ng, K. W.; Yuan, Z. M.; Zong, B. Y.; Shi, J. Z.; Hendra, S. K.; Liu, B.; Ng, V.

    2009-04-01

    Multi-row-per-track discrete bit patterned media with interleaved bits have been fabricated on granular perpendicular media disks by focused ion beam and tested by magnetic force microscopy and spinstand tester. It was found that sub-100 nm patterned magnetic islands showed single domain behavior and narrowed switching field distribution. We further demonstrate from captured spinstand readback waveforms the concept of recording two rows of interleaved dot bits as one track. In addition to overcoming the down track patterning resolution limit, the proposed concept patterned media provide many other advantages including higher data rate for read/write, a flexible bit aspect ratio (BAR)≥2 design for better integration with head design and servo control, as well as allowing the use of wider write pole to improve writing efficiency for high density recording.

  7. Development and assessment of the Monark cycle ergometer for anaerobic muscular exercise

    NASA Astrophysics Data System (ADS)

    Frederick, F. A.; Langevin, R. C.; Miletti, J.; Sacco, M.; Murphy, M. M.

    1983-07-01

    This report describes the system developed by this Institute to measure anaerobic power production using the protocol developed at the Wingate Institute in Israel. This test consists of 30 seconds of maximal cycling (or cranking) exercise against a resistance determined according to the body weight of the subject. The system consists of a modified Monark cycle ergometer, a universal counter to monitor flywheel revolutions, and a desktop computer for timing, control, and data processing. The modification of the ergometer for the instantaneous application of resistance is presented. In addition, the methods used to measure pedal revolutions and to calibrate the ergometer, and the analysis of the forces acting on the flywheel are described. Finally, a description of the procedure used in the performance of the Wingate test and a summary of the actual data output are presented.

  8. Row fault detection system

    DOEpatents

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2010-02-23

    An apparatus and program product check for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  9. Row fault detection system

    DOEpatents

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2008-10-14

    An apparatus, program product and method checks for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  10. Designing ROW Methods

    NASA Technical Reports Server (NTRS)

    Freed, Alan D.

    1996-01-01

    There are many aspects to consider when designing a Rosenbrock-Wanner-Wolfbrandt (ROW) method for the numerical integration of ordinary differential equations (ODE's) solving initial value problems (IVP's). The process can be simplified by constructing ROW methods around good Runge-Kutta (RK) methods. The formulation of a new, simple, embedded, third-order, ROW method demonstrates this design approach.

  11. Row fault detection system

    DOEpatents

    Archer, Charles Jens [Rochester, MN; Pinnow, Kurt Walter [Rochester, MN; Ratterman, Joseph D [Rochester, MN; Smith, Brian Edward [Rochester, MN

    2012-02-07

    An apparatus, program product and method check for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  12. A Biomechanical Assessment of Ergometer Task Specificity in Elite Flatwater Kayakers

    PubMed Central

    Fleming, Neil; Donne, Bernard; Fletcher, David; Mahony, Nick

    2012-01-01

    The current study compared EMG, stroke force and 2D kinematics during on-ergometer and on-water kayaking. Male elite flatwater kayakers (n = 10) performed matched exercise protocols consisting of 3 min bouts at heart and stroke rates equivalent to 85% of VO2peak (assessed by prior graded incremental test). EMG data were recorded from Anterior Deltoid (AD), Triceps Brachii (TB), Latissimus Dorsi (LD) and Vastus Lateralis (VL) via wireless telemetry. Video data recorded at 50 Hz with audio triggers pre- and post-exercise facilitated synchronisation of EMG and kinematic variables. Force data were recorded via strain gauge arrays on paddle and ergometer shafts. EMG data were root mean squared (20ms window), temporally and amplitude normalised, and averaged over 10 consecutive cycles. In addition, overall muscle activity was quantified via iEMG and discrete stroke force and kinematic variables computed. Significantly greater TB and LD mean iEMG activity were recorded on-water (239 ± 15 vs. 179 ± 10 μV. s, p < 0.01 and 158 ± 12 vs. 137 ± 14 μV.s, p < 0.05, respectively), while significantly greater AD activity was recorded on-ergometer (494 ± 66 vs. 340 ± 35 μV.s, p < 0.01). Time to vertical shaft position occurred significantly earlier on-ergometer (p < 0.05). Analysis of stroke force data and EMG revealed that increased AD activity was concurrent with increased external forces applied to the paddle shaft at discrete phases of the on-ergometer stroke cycle. These external forces were associated with the ergometer loading mechanism and were not observed on- water. The current results contradict a previous published hypothesis on shoulder muscle recruitment during on-water kayaking. Key pointsWhen exercising at fixed heart and stroke rates, biomechanical differences exist between onergometer and on-water kayaking.Ergometer kayaking results in significantly greater Anterior Deltoid activity but significantly lower Triceps Brachii and Latissimus Dorsi activity

  13. Forelimb muscle function in pig-nosed turtles, Carettochelys insculpta: testing neuromotor conservation between rowing and flapping in swimming turtles

    PubMed Central

    Rivera, Angela R. V.; Blob, Richard W.

    2013-01-01

    Changes in muscle activation patterns can lead to new locomotor modes; however, neuromotor conservation—the evolution of new forms of locomotion through changes in structure without concurrent changes to underlying motor patterns—has been documented across diverse styles of locomotion. Animals that swim using appendages do so via rowing (anteroposterior oscilations) or flapping (dorsoventral oscilations). Yet few studies have compared motor patterns between these swimming modes. In swimming turtles, propulsion is generated exclusively by limbs. Kinematically, turtles swim using multiple styles of rowing (freshwater species), flapping (sea turtles) and a unique hybrid style with superficial similarity to flapping by sea turtles and characterized by increased dorsoventral motions of synchronously oscillated forelimbs that have been modified into flippers (Carettochelys insculpta). We compared forelimb motor patterns in four species of turtle (two rowers, Apalone ferox and Trachemys scripta; one flapper, Caretta caretta; and Carettochelys) and found that, despite kinematic differences, motor patterns were generally similar among species with a few notable exceptions: specifically, presence of variable bursts for pectoralis and triceps in Trachemys (though timing of the non-variable pectoralis burst was similar), and the timing of deltoideus activity in Carettochelys and Caretta compared with other taxa. The similarities in motor patterns we find for several muscles provide partial support for neuromotor conservation among turtles using diverse locomotor styles, but the differences implicate deltoideus as a prime contributor to flapping limb motions. PMID:23966596

  14. Forelimb muscle function in pig-nosed turtles, Carettochelys insculpta: testing neuromotor conservation between rowing and flapping in swimming turtles.

    PubMed

    Rivera, Angela R V; Blob, Richard W

    2013-10-23

    Changes in muscle activation patterns can lead to new locomotor modes; however, neuromotor conservation-the evolution of new forms of locomotion through changes in structure without concurrent changes to underlying motor patterns-has been documented across diverse styles of locomotion. Animals that swim using appendages do so via rowing (anteroposterior oscilations) or flapping (dorsoventral oscilations). Yet few studies have compared motor patterns between these swimming modes. In swimming turtles, propulsion is generated exclusively by limbs. Kinematically, turtles swim using multiple styles of rowing (freshwater species), flapping (sea turtles) and a unique hybrid style with superficial similarity to flapping by sea turtles and characterized by increased dorsoventral motions of synchronously oscillated forelimbs that have been modified into flippers (Carettochelys insculpta). We compared forelimb motor patterns in four species of turtle (two rowers, Apalone ferox and Trachemys scripta; one flapper, Caretta caretta; and Carettochelys) and found that, despite kinematic differences, motor patterns were generally similar among species with a few notable exceptions: specifically, presence of variable bursts for pectoralis and triceps in Trachemys (though timing of the non-variable pectoralis burst was similar), and the timing of deltoideus activity in Carettochelys and Caretta compared with other taxa. The similarities in motor patterns we find for several muscles provide partial support for neuromotor conservation among turtles using diverse locomotor styles, but the differences implicate deltoideus as a prime contributor to flapping limb motions.

  15. No influence of hypoxia on coordination between respiratory and locomotor rhythms during rowing at moderate intensity.

    PubMed

    Fabre, Nicolas; Perrey, Stéphane; Passelergue, Philippe; Rouillon, Jean-Denis

    2007-01-01

    Besides neuro-mechanical constraints, chemical or metabolic stimuli have also been proposed to interfere with the coordination between respiratory and locomotor rhythms. In the light of the conflicting data observed in the literature, this study aimed to assess whether acute hypoxia modifies the degree of coordination between respiratory and locomotor rhythms during rowing exercises in order to investigate competitive interactions between neuro-mechanical (movement) and chemical (hypoxia) respiratory drives. Nine male healthy subjects performed one submaximal 6-min rowing exercise on a rowing ergometer in both normoxia (altitude: 304 m) and acute hypoxia (altitude: 2877 m). The exercise intensity was about 40 % and 35 % (for normoxia and hypoxia conditions, respectively) of the individual maximal power output measured during an incremental rowing test to volitional exhaustion carried out in normoxia. Metabolic rate and minute ventilation were continuously collected throughout exercise. Locomotor movement and breathing rhythms were continuously recorded and synchronized cycle-by-cycle. The degree of coordination was expressed as a percentage of breaths starting during the same phase of the locomotor cycle. For a same and a constant metabolic rate, acute hypoxia did not influence significantly the degree of coordination (mean ± SEM, normoxia: 20.0 ± 6.2 %, hypoxia: 21.3 ± 11.1 %, p > 0.05) while ventilation and breathing frequency were significantly greater in hypoxia. Our results may suggest that during rowing exercise at a moderate metabolic load, neuro-mechanical locomotion-linked respiratory stimuli appear "stronger "than peripheral chemoreceptors- linked respiratory stimuli induced by hypoxia, in the context of our study. Key pointsChanges in breathing frequency and ventilation induced by altitude have no effect on the degree of coordination between locomotor and breathing rhythms during moderate rowing exercise.During moderate rowing exercise in hypoxia, the

  16. No Influence of Hypoxia on Coordination Between Respiratory and Locomotor Rhythms During Rowing at Moderate Intensity

    PubMed Central

    Fabre, Nicolas; Perrey, Stéphane; Passelergue, Philippe; Rouillon, Jean-Denis

    2007-01-01

    Besides neuro-mechanical constraints, chemical or metabolic stimuli have also been proposed to interfere with the coordination between respiratory and locomotor rhythms. In the light of the conflicting data observed in the literature, this study aimed to assess whether acute hypoxia modifies the degree of coordination between respiratory and locomotor rhythms during rowing exercises in order to investigate competitive interactions between neuro-mechanical (movement) and chemical (hypoxia) respiratory drives. Nine male healthy subjects performed one submaximal 6-min rowing exercise on a rowing ergometer in both normoxia (altitude: 304 m) and acute hypoxia (altitude: 2877 m). The exercise intensity was about 40 % and 35 % (for normoxia and hypoxia conditions, respectively) of the individual maximal power output measured during an incremental rowing test to volitional exhaustion carried out in normoxia. Metabolic rate and minute ventilation were continuously collected throughout exercise. Locomotor movement and breathing rhythms were continuously recorded and synchronized cycle-by-cycle. The degree of coordination was expressed as a percentage of breaths starting during the same phase of the locomotor cycle. For a same and a constant metabolic rate, acute hypoxia did not influence significantly the degree of coordination (mean ± SEM, normoxia: 20.0 ± 6.2 %, hypoxia: 21.3 ± 11.1 %, p > 0.05) while ventilation and breathing frequency were significantly greater in hypoxia. Our results may suggest that during rowing exercise at a moderate metabolic load, neuro-mechanical locomotion-linked respiratory stimuli appear “stronger ”than peripheral chemoreceptors- linked respiratory stimuli induced by hypoxia, in the context of our study. Key pointsChanges in breathing frequency and ventilation induced by altitude have no effect on the degree of coordination between locomotor and breathing rhythms during moderate rowing exercise.During moderate rowing exercise in hypoxia

  17. Gross efficiency during rowing is not affected by stroke rate.

    PubMed

    Hofmijster, Mathijs J; Van Soest, Arthur J; De Koning, Jos J

    2009-05-01

    It has been suggested that the optimal stroke rate in rowing is partly determined by the stroke-rate dependence of internal power losses. This should be reflected in a stroke-rate dependency of gross efficiency (e(gross)). The purpose of this study was to investigate if e(gross) is affected by stroke rate. A second aim was to determine whether internal power losses can be estimated by the negative power output during the stroke cycle (P(negative)). Seventeen well-trained female rowers participated in this study. They rowed three trials on a modified rowing ergometer on slides at a submaximal intensity, with a respiratory exchange ratio of 1 or close to 1. Stroke rates were 28, 34, and 40 strokes per minute. The trials were fully randomized. Power transfer to the flywheel was kept constant whereas e(gross) was determined during each trial. No significant differences in e(gross) were found between conditions. This finding suggests that in rowing internal power losses are not influenced by stroke rate. Furthermore, although P(negative) increased at increasing stroke rate (P < 0.001), no relationship was found with e(gross). This suggests that P(negative) is not a reliable measure to estimate internal power losses. This study shows that within the range of stroke rates applied in competitive rowing, internal power losses are unrelated to rowing cycle frequency.

  18. Biomechanics of Rowing

    NASA Astrophysics Data System (ADS)

    Hase, Kazunori; Kaya, Motoshi; Yamazaki, Nobutoshi; Andrews, Brian J.; Zavatsky, Amy B.; Halliday, Suzanne E.

    Compared with the other exercise, such as walking and cycling, rowing was expected to have some fitness advantage, while there were some misgivings about the risk of injury. The objectives of this study were to quantify biomechanical characteristics of rowing for fitness and rehabilitation and to offer normative data for the prevention of injury and for determining effective exercise. An experiment was performed to collect the kinematic and kinetic data during rowing by experienced and non-experienced subjects. A three-dimensional whole-body musculo-skeletal model was used to calculate the biomechanical loads, such as the joint moments, the muscular tensions, the joint contact forces and the energy consumption. The results of this study indicate that rowing is an effective exercise for rehabilitation and fitness. However, the non-experienced rower should acquire considerable skill to obtain sufficient exercise. The rowing cadence should be decided according to the purpose of the exercise.

  19. Suicide on Death Row.

    PubMed

    Tartaro, Christine; Lester, David

    2016-11-01

    Despite the level of supervision of inmates on death row, their suicide rate is higher than both the male prison population in the United States and the population of males over the age of 14 in free society. This study presents suicide data for death row inmates from 1978 through 2010. For the years 1978 through 2010, suicide rates on death row were higher than that for the general population of males over the age of 15 and for state prisons for all but 2 years.

  20. Physics of rowing

    NASA Astrophysics Data System (ADS)

    Boucher, Jean-Philippe; Labbe, Romain; Mouterde, Timothee; Clanet, Christophe

    2016-11-01

    Synchronization in rowing seems like a crucial condition for those who aim at winning top-level rowing races. However, in nature, one can observe animals with many legs, such as krill, swimming in a desynchronized manner which is nearly metachronal. From a physicist point of view, rowing by following a metachronal wave also seems like a great idea because, at high Reynolds number, the metachronal gait has one big advantage over the synchronized gait: it reduces the fluctuations of speed and thus the drag on the body. In this experimental study, we have built a scale model of a rowing boat to deal with the question of the effect of synchronization on the boat performance.

  1. Mechanical efficiency in rowing.

    PubMed

    Fukunaga, T; Matsuo, A; Yamamoto, K; Asami, T

    1986-01-01

    Five university oarsmen participated in a determination of mechanical efficiency when rowing in a tank. In the tank, water was circulated at 3 m X s-1 by a motor driven pump. The subjects rowed with the stepwise incremental loading, in which the intensity increased by 10% of the maximum force of rowing (maxFc) every 2 min. Power (WO) was calculated from the force applied to the oarlock pin (FC) and its angular displacement (theta H). Oxygen uptake and heart rate were measured every 30 s during rowing. Anaerobic threshold (AT) was determined from expired gas variables by Wasserman's method. AT of oarsmen was 74.6 +/- 6.01% as a percentage of VO2max. As the displacement of the handgrip in the stroke was independent of WO, the increment of WO was caused by the increase of both FC and stroke frequency. Gross efficiency without base-line correction (GE) increased with FC with low intensities of rowing. In the region of 124-182 W of WO GE was almost constant at 17.5%. Efficiency was 19.8 +/- 1.4%, with resting metabolism as base-line correction (net efficiency), and 27.5 +/- 2.9% when using the unloaded rowing as the base-line correction (work efficiency), and 22.8 +/- 2.2% when calculating the work rate as the base-line correction (delta efficiency).

  2. Astronaut Gerald Carr sits on the bicycle ergometer during prelaunch

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Gerald P. Carr, Skylab 4 mission commander, sits on the bicycle ergometer as he takes part in the body mass measurement experiment during a prelaunch physical examination for the crew of the third manned mission.

  3. Wakata on Cycle Ergometer with Vibration Isolation System (CEVIS)

    NASA Image and Video Library

    2009-03-30

    ISS018-E-043723 (30 March 2009) --- Japan Aerospace Exploration Agency (JAXA) astronaut Koichi Wakata, Expedition 18/19 flight engineer, exercises on the Cycle Ergometer with Vibration Isolation System (CEVIS) in the Destiny laboratory of the International Space Station.

  4. Fincke uses Cycle Ergometer with Vibration Isolation System (CEVIS)

    NASA Image and Video Library

    2009-03-26

    ISS018-E-043414 (26 March 2009) --- Astronaut Michael Fincke, Expedition 18 commander, exercises on the Cycle Ergometer with Vibration Isolation System (CEVIS) in the Destiny laboratory of the International Space Station.

  5. Astronaut Gerald Carr sits on the bicycle ergometer during prelaunch

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Gerald P. Carr, Skylab 4 mission commander, sits on the bicycle ergometer as he takes part in the body mass measurement experiment during a prelaunch physical examination for the crew of the third manned mission.

  6. Sturckow uses Cycle Ergometer on Middeck (MDDK) during STS-128

    NASA Image and Video Library

    2009-08-29

    S128-E-006315 (29 Aug. 2009) --- Astronaut Rick Sturckow, STS-128 commander, gives a “thumbs-up” signal while exercising on a bicycle ergometer on the middeck of the Earth-orbiting Space Shuttle Discovery.

  7. The Measurement of Maximal (Anaerobic) Power Output on a Cycle Ergometer: A Critical Review

    PubMed Central

    Driss, Tarak; Vandewalle, Henry

    2013-01-01

    The interests and limits of the different methods and protocols of maximal (anaerobic) power (P max) assessment are reviewed: single all-out tests versus force-velocity tests, isokinetic ergometers versus friction-loaded ergometers, measure of P max during the acceleration phase or at peak velocity. The effects of training, athletic practice, diet and pharmacological substances upon the production of maximal mechanical power are not discussed in this review mainly focused on the technical (ergometer, crank length, toe clips), methodological (protocols) and biological factors (muscle volume, muscle fiber type, age, gender, growth, temperature, chronobiology and fatigue) limiting P max in cycling. Although the validity of the Wingate test is questionable, a large part of the review is dedicated to this test which is currently the all-out cycling test the most often used. The biomechanical characteristics specific of maximal and high speed cycling, the bioenergetics of the all-out cycling exercises and the influence of biochemical factors (acidosis and alkalosis, phosphate ions…) are recalled at the beginning of the paper. The basic knowledge concerning the consequences of the force-velocity relationship upon power output, the biomechanics of sub-maximal cycling exercises and the study on the force-velocity relationship in cycling by Dickinson in 1928 are presented in Appendices. PMID:24073413

  8. The measurement of maximal (anaerobic) power output on a cycle ergometer: a critical review.

    PubMed

    Driss, Tarak; Vandewalle, Henry

    2013-01-01

    The interests and limits of the different methods and protocols of maximal (anaerobic) power (Pmax) assessment are reviewed: single all-out tests versus force-velocity tests, isokinetic ergometers versus friction-loaded ergometers, measure of Pmax during the acceleration phase or at peak velocity. The effects of training, athletic practice, diet and pharmacological substances upon the production of maximal mechanical power are not discussed in this review mainly focused on the technical (ergometer, crank length, toe clips), methodological (protocols) and biological factors (muscle volume, muscle fiber type, age, gender, growth, temperature, chronobiology and fatigue) limiting Pmax in cycling. Although the validity of the Wingate test is questionable, a large part of the review is dedicated to this test which is currently the all-out cycling test the most often used. The biomechanical characteristics specific of maximal and high speed cycling, the bioenergetics of the all-out cycling exercises and the influence of biochemical factors (acidosis and alkalosis, phosphate ions…) are recalled at the beginning of the paper. The basic knowledge concerning the consequences of the force-velocity relationship upon power output, the biomechanics of sub-maximal cycling exercises and the study on the force-velocity relationship in cycling by Dickinson in 1928 are presented in Appendices.

  9. Scottish Short Stone Rows

    NASA Astrophysics Data System (ADS)

    Ruggles, Clive L. N.

    Short stone rows received a good deal of attention during the 1980s and 1990s, at a time when archaeoastronomy in prehistoric Britain and Ireland was moving beyond reassessments of Alexander Thom's "megalithic observatories" by identifying coherent groups of similar monuments with clear orientation trends. Many such rows are found in western Scotland, with the main concentration in Argyll and the island of Mull. Systematic analyses of their orientations produced credible evidence of an awareness of the 18.6-year lunar node cycle, within a "primary-secondary" pattern whereby isolated rows were oriented close to moonrise or moonset at the southern major standstill limit, while others oriented in this way were accompanied by a second row oriented in a declination range that could be interpreted either as lunar or solar. A detailed investigation of the landscape situation of the sites in northern Mull, accompanied by excavations at two of the sites, suggested that they were deliberately placed in locations where critical moonsets would be seen against prominent distant landscape features, but where the distant horizon in most or all other directions was hidden from view. A lack of independent archaeological evidence may help to explain why archaeoastronomical investigations at short stone rows have never progressed beyond "data-driven" studies of orientations and landscape situation. Nonetheless, the work that was done at these sites raised important general methodological issues, and pioneered techniques, that remain relevant across archaeoastronomy today.

  10. Generic Verification Protocol for Testing Pesticide Application Spray Drift Reduction Technologies for Row and Field Crops (Version 1.4)

    EPA Science Inventory

    This generic verification protocol provides a detailed method for conducting and reporting results from verification testing of pesticide application technologies. It can be used to evaluate technologies for their potential to reduce spray drift, hence the term “drift reduction t...

  11. Generic Verification Protocol for Testing Pesticide Application Spray Drift Reduction Technologies for Row and Field Crops (Version 1.4)

    EPA Science Inventory

    This generic verification protocol provides a detailed method for conducting and reporting results from verification testing of pesticide application technologies. It can be used to evaluate technologies for their potential to reduce spray drift, hence the term “drift reduction t...

  12. Biomechanics of Rowing

    NASA Astrophysics Data System (ADS)

    Hase, Kazunori; Andrews, Brian J.; Zavatsky, Amy B.; Halliday, Suzanne E.

    A new control model for the study of biomechanical simulation of human movement was investigated using rowing as an example. The objectives were to explore biological and mechanical alternatives to optimal control methods. The simulation methods included simple control mechanisms based on proportional and derivative (PD) control, consideration of a simple neural model, introduction of an inverse dynamics system for feedback, and computational adjustment of control parameters by using an evaluative criterion and optimization method. By using simulation, appropriate rowing motions were synthesized. The generated rowing motion was periodic, continuous, and adaptable so that the pattern was stable against the mechanical force and independent of the initial condition. We believe that the simulation model is not only practical as a computational research tool from a biomechanical-engineering viewpoint but also significant from the point of view of fundamental biological theories of movement.

  13. Evaluation of the Monark Wingate ergometer by direct measurement of resistance and velocity.

    PubMed

    MacIntosh, B R; Bryan, S N; Rishaug, P; Norris, S R

    2001-12-01

    The purpose of this study was to assess the accuracy of the new basket-loaded Wingate ergometer introduced by Monark (Model 834E). Velocity was measured directly from the pedal switch while tension was measured with transducers on each end of the brake lacing. Moment of inertia of the flywheel was determined and accounted for in the calculation of power. Constant load tests (39.24 to 98.1 N), were done at pedaling speeds from 80 to 140 r x min(-1) (flywheel angular velocity = 30-50 rad x s(-1)). The load transmitted to the lacing at the front and back of the flywheel was 95.5 +/- 0.8% (mean +/- SEM) and 6.71 +/- 0.8%, respectively, of the load in the basket. Thus, the resultant tension (front minus back) was on average 88.8 +/- 0.57% of the applied load. The velocity recorded by the Monark Wingate Ergometer computer program (MWECP) was the same (100.4 +/- 1.56%) as that determined from the pedal switch directly. Five male mountain bikers performed a 30-s all-out test. Peak power calculated by MWECP (1181 +/- 55W) was always higher (p < .01) than that calculated from direct measures of tension and velocity (1102 +/- 66W), when not taking into account the moment of inertia. These experiments suggest that the basket-loaded Monark Wingate ergometer does not provide a correct calculation of power because of incomplete load transmission to the flywheel.

  14. A simple calibration method for mechanically braked cycle ergometers.

    PubMed

    Van Praagh, E; Bedu, M; Roddier, P; Coudert, J

    1992-01-01

    The calibration of cycle ergometers should be checked regularly. Some studies have shown calibration errors of more than 40%. A simple, inexpensive calibrating method for mechanically braked cycle ergometers was developed and tried out on a new type of ergocycle. The cycle ergometer was elevated and the crank replaced by a pulley fitted to the shaft. The crank speed (rpm) increased linearly as a function of time when different masses were applied on the pulley. For a given braking force on the cycle ergometer, different accelerations corresponding to the increased pulley forces could be measured. When extrapolating for zero acceleration, it was possible to determine a "limit-force" which allowed the system to be in equilibrium. Additional force creates motion. The same experiments were repeated with increasing braking forces. Using the differently sized gear sprockets of the transmission system, it was possible to calculate the actual force, including all the resistances. The actual force found by the calibrating method was then compared with the indicated force proposed by the manufacturer. With increasing forces, the relative errors decreased from 9.6 to 2.9%. The cycle ergometer calibrated by this technique meets the standards recommended in exercise physiology.

  15. Exhaled methane concentration profiles during exercise on an ergometer

    PubMed Central

    Szabó, A; Ruzsanyi, V; Unterkofler, K; Mohácsi, Á; Tuboly, E; Boros, M; Szabó, G; Hinterhuber, H; Amann, A

    2016-01-01

    Exhaled methane concentration measurements are extensively used in medical investigation of certain gastrointestinal conditions. However, the dynamics of endogenous methane release is largely unknown. Breath methane profiles during ergometer tests were measured by means of a photoacoustic spectroscopy based sensor. Five methane-producing volunteers (with exhaled methane level being at least 1 ppm higher than room air) were measured. The experimental protocol consisted of 5 min rest—15 min pedalling (at a workload of 75 W)—5 min rest. In addition, hemodynamic and respiratory parameters were determined and compared to the estimated alveolar methane concentration. The alveolar breath methane level decreased considerably, by a factor of 3–4 within 1.5 min, while the estimated ventilation-perfusion ratio increased by a factor of 2–3. Mean pre-exercise and exercise methane concentrations were 11.4 ppm (SD:7.3) and 2.8 ppm (SD:1.9), respectively. The changes can be described by the high sensitivity of exhaled methane to ventilationperfusion ratio and are in line with the Farhi equation. PMID:25749807

  16. Shoulder muscle strength in paraplegics before and after kayak ergometer training.

    PubMed

    Bjerkefors, Anna; Jansson, Anna; Thorstensson, Alf

    2006-07-01

    The purpose was to investigate if shoulder muscle strength in post-rehabilitated persons with spinal cord injury (SCI) was affected by kayak ergometer training and to compare shoulder strength in persons with SCI and able-bodied persons. Ten persons with SCI (7 males and 3 females, injury levels T3-T12) performed 60 min kayak ergometer training three times a week for 10 weeks with progressively increased intensity. Maximal voluntary concentric contractions were performed during six shoulder movements: flexion and extension (range of motion 65 degrees ), abduction and adduction (65 degrees ), and external and internal rotation (60 degrees ), with an angular velocity of 30 degrees s(-1). Position specific strength was assessed at three shoulder angles (at the beginning, middle and end of the range of motion) in the respective movements. Test-retests were performed for all measurements before the training and the mean intraclass correlation coefficient was 0.941 (95% CI 0.928-0.954). There was a main effect of kayak ergometer training with increased shoulder muscle strength after training in persons with SCI. The improvements were independent of shoulder movement, and occurred in the beginning and middle positions. A tendency towards lower shoulder muscle strength was observed in the SCI group compared to a matched reference group of able-bodied persons. Thus, it appears that post-rehabilitated persons with SCI have not managed to fully regain/maintain their shoulder muscle strength on a similar level as that of able-bodied persons, and are able to improve their shoulder muscle strength after a period of kayak ergometer training.

  17. Skylab-3 Mission Onboard Photograph - Astronaut Bean on Ergometer

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This Skylab-3 onboard photograph shows Astronaut Allen Bean on the ergometer, breathing into the metabolic analyzer. Skylab's Metabolic Activity experiment (M171), a medical evaluation facility, was designed to measure astronauts' metabolic changes while on long-term space missions. The experiment obtained information on astronauts' physiological capabilities and limitations and provided data useful in the design of future spacecraft and work programs. Physiological responses to physical activity was deduced by analyzing inhaled and exhaled air, pulse rate, blood pressure, and other selected variables of the crew while they performed controlled amounts of physical work with a bicycle ergometer.

  18. Skylab-3 Mission Onboard Photograph - Astronaut Bean on Ergometer

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This Skylab-3 onboard photograph shows Astronaut Allen Bean on the ergometer, breathing into the metabolic analyzer. Skylab's Metabolic Activity experiment (M171), a medical evaluation facility, was designed to measure astronauts' metabolic changes while on long-term space missions. The experiment obtained information on astronauts' physiological capabilities and limitations and provided data useful in the design of future spacecraft and work programs. Physiological responses to physical activity was deduced by analyzing inhaled and exhaled air, pulse rate, blood pressure, and other selected variables of the crew while they performed controlled amounts of physical work with a bicycle ergometer.

  19. Induced alkalosis and caffeine supplementation: effects on 2,000-m rowing performance.

    PubMed

    Carr, Amelia J; Gore, Christopher J; Dawson, Brian

    2011-10-01

    The purpose of this investigation was to determine the effect of ingested caffeine, sodium bicarbonate, and their combination on 2,000-m rowing performance, as well as on induced alkalosis (blood and urine pH and blood bicarbonate concentration [HCO3-]), blood lactate concentration ([La-]), gastrointestinal symptoms, and rating of perceived exertion (RPE). In a double-blind, crossover study, 8 well-trained rowers performed 2 baseline tests and 4 × 2,000-m rowing-ergometer tests after ingesting 6 mg/kg caffeine, 0.3 g/kg body mass (BM) sodium bicarbonate, both supplements combined, or a placebo. Capillary blood samples were collected at preingestion, pretest, and posttest time points. Pairwise comparisons were made between protocols, and differences were interpreted in relation to the likelihood of exceeding the smallest worthwhile-change thresholds for each variable. A likelihood of >75% was considered a substantial change. Caffeine supplementation elicited a substantial improvement in 2,000-m mean power, with mean (± SD) values of 354 ± 67 W vs. placebo with 346 ± 61 W. Pretest [HCO3-] reached 29.2 ± 2.9 mmol/L with caffeine + bicarbonate and 29.1 ± 1.9 mmol/L with bicarbonate. There were substantial increases in pretest [HCO3-] and pH and posttest urine pH after bicarbonate and caffeine + bicarbonate supplementation compared with placebo, but unclear performance effects. Rowers' performance in 2,000-m efforts can improve by ~2% with 6 mg/kg BM caffeine supplementation. When caffeine is combined with sodium bicarbonate, gastrointestinal symptoms may prevent performance enhancement, so further investigation of ingestion protocols that minimize side effects is required.

  20. Fuel metabolism during severe rowing exercise

    SciTech Connect

    Hoyt, R.W.; Lubowitz, J.; Asakura, T.; Stein, T.P.

    1986-03-01

    Eight elite oarsmen were studied during and after six min of severe ergometer exercise. Power output averaged 380 +/- 28 watts. Serial venous blood samples and gas exchange measurements were obtained during exercise. In 4 of the 8 subjects, a primed periodic oral dose of the tracer (6,6-/sup 2/H/sub 2/)glucose was used to determine the effects of severe exercise on glucose metabolism. During exercise, the levels of lactate progressively increased to 12.2 +/- 1.3 mM (SE). There was little change in isotopic glucose enrichment during exercise (from 2.95 +/- 0.30 to 2.55 +/- 0.23 atom percent excess, APE). During recovery, isotopic glucose enrichment decreased significantly to 1.40 +/- 0.14 APE, indicating a substantial post-exercise plasma glucose flux. There were significant post-exercise increases in plasma glucose accumulation (from 84 +/- 5 to 131 +/- 3 mg/dl) and insulin concentration (0.57 +/- 0.08 to 1.34 +/- 0.15 ng/ml). These results suggest that muscle glycogen is the primary source of fuel during six minutes of maximal rowing exercise.

  1. Yankee Rowe simulator core model validation

    SciTech Connect

    Napolitano, M.E.

    1990-01-01

    This paper presents the validation of the Yankee Rowe simulator core model. Link-Miles Simulation Corporation is developing the Yankee Rowe simulator and Yankee Atomic Electric Company is involved in input and benchmark data generation, as well as simulator validation. Core model validation by Yankee comprises three tasks: (1) careful generation of fuel reactivity characteristics (B constants); (2) nonintegrated core model testing; and (3) fully integrated core model testing. Simulator core model validation and verification is a multistage process involving input and benchmark data generation as well as interactive debugging. Core characteristics were brought within acceptable criteria by this process. This process was achieved through constant communication between Link-Miles and Yankee engineers. Based on this validation, the Yankee Rowe simulator core model is found to be acceptable for training purposes.

  2. Astronauts Grunsfeld and Lawrence on middeck with ergometer

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Astronauts John M. Grunsfeld and Wendy B. Lawrence exercise on the middeck of the Earth-orbiting Space Shuttle Endeavour during the STS-67 mission. While Grunsfeld's pedaling is done on a real bicycle ergometer, Lawrence's movements are a convincing simulation without hardware.

  3. Tilt table for ergometers and other biomedical devices

    NASA Technical Reports Server (NTRS)

    Gause, R. L.; Spier, R. A.

    1971-01-01

    Table adjusts to any position between horizontal and vertical. Apparatus includes - floor plate, plate hinged to floor plate, for carrying ergometer, hydraulic cylinder and piston on plate sides, linking them, hydraulic system, positive stops, padded backrest and headrest, one hand controls, and constraint system.

  4. Sturckow uses Cycle Ergometer on Middeck (MDDK) during STS-128

    NASA Image and Video Library

    2009-08-29

    S128-E-006313 (29 Aug. 2009) --- Astronaut Rick Sturckow, STS-128 commander, gives a “thumbs-up” signal while exercising on a bicycle ergometer on the middeck of the Earth-orbiting Space Shuttle Discovery. Astronaut Nicole Stott, mission specialist, is visible at right.

  5. Kopra on ergometer in U.S. Lab

    NASA Image and Video Library

    2009-07-23

    ISS020-E-023565 (23 July 2009) --- Astronaut Tim Kopra works out on the International Space Station's bicycle ergometer in the U.S. lab, Destiny. Kopra has only recently joined the Expedition 20 crew as a flight engineer, having arrived at the orbital outpost via the Space Shuttle Endeavour.

  6. Validity of arm-leg elliptical ergometer for VO2max analysis.

    PubMed

    Brown, Andrew B; Kueffner, Tannin E; OʼMahony, Erin C; Lockard, Michael M

    2015-06-01

    Maximal oxygen consumption ((Equation is included in full-text article.)) can be determined through multiple exercise modalities intended to elicit an individual's maximal aerobic exertion. Uphill treadmill running is considered the best modality for measuring (Equation is included in full-text article.). Previous studies have examined correlations between treadmill and elliptical ergometer tests as well as the cycle ergometer, but none of the studies use an arm-leg elliptical ergometer (ALE). The purpose of this study was to develop an ALE (Equation is included in full-text article.)testing protocol and determine whether ALE produces valid (Equation is included in full-text article.)values as compared with the treadmill. Twelve undergraduate students (mean age: 20.8 years) completed 2 (Equation is included in full-text article.)tests, 1 on a treadmill and 1 on ALE. (Equation is included in full-text article.)correlation between ALE and treadmill was examined, and paired t-tests were run for (Equation is included in full-text article.)and maximum heart rate (HRmax). A strong positive correlation was found between ALE and treadmill (Equation is included in full-text article.)values (r = 0.84; p < 0.001). There were no differences between (Equation is included in full-text article.)values; however, HRmax values were higher on the treadmill than ALE (p = 0.003). Although future research is needed to examine the observed differences in HRmax between the 2 testing modalities and gender differences in muscle recruitment patterns, the results of this study suggest that ALE is a valid modality for (Equation is included in full-text article.)testing. This will be particularly valuable as a clinical tool to assess (Equation is included in full-text article.)in populations requiring low-impact exercise.

  7. Intensive cycle ergometer training improves gait speed and endurance in patients with Parkinson's disease: A comparison with treadmill training.

    PubMed

    Arcolin, Ilaria; Pisano, Fabrizio; Delconte, Carmen; Godi, Marco; Schieppati, Marco; Mezzani, Alessandro; Picco, Daniele; Grasso, Margherita; Nardone, Antonio

    2015-01-01

    Cycle ergometer training improves gait in the elderly, but its effect in patients with Parkinson's disease (PD) is not completely known. Twenty-nine PD inpatients were randomized to treadmill (n = 13, PD-T) or cycle ergometer (n = 16, PD-C) training for 3 weeks, 1 hour/day. Outcome measures were distance travelled during the 6-min walking test (6MWT), spatio-temporal variables of gait assessed by baropodometry, the Timed Up and Go (TUG) duration, the balance score through the Mini-BESTest, and the score of the Unified Parkinson's Disease Rating Scale (UPDRS). Sex, age, body mass index, disease duration, Hoehn-Yahr staging, comorbidity and medication did not differ between groups. At end of training, ANCOVA showed significant improvement, of similar degree, in both groups for 6MWT, speed, step length and cadence of gait, TUG, Mini-BESTest and UPDRS. This pilot study shows that cycle ergometer training improves walking parameters and reduces clinical signs of PD, as much as treadmill training does. Gait velocity is accompanied by step lengthening, making the gait pattern close to that of healthy subjects. Cycle ergometer is a valid alternative to treadmill for improving gait in short term in patients with PD.

  8. Rowing competitions and perspective

    NASA Astrophysics Data System (ADS)

    Flores, Alfinio; Bernhardt, Stephen A.; Shipman, Henry L.

    2015-02-01

    This paper is about integrating the use of graphing technology (specifically, GeoGebra) with principles of motion, principles of perspective, and the concept of vanishing points to model a dynamic event. Students were asked to analyse video images of a rowing competition filmed with a single camera positioned perpendicular to the race. The fixed position of the camera in such races makes it difficult to determine whether a scull closer to the camera is actually overtaking another, more distant scull. The paper illustrates how students in their first year at the university can integrate the use of technology, science, mathematics, and writing to solve a real world problem involving motion.

  9. LBNP/ergometer effects on female cardiovascular and muscle deconditioning in 15d head-down bed rest

    NASA Astrophysics Data System (ADS)

    Wang, Lin-Jie

    2012-07-01

    Female has already been an important part of astronaut corps but gender characteristics in weightlessness and countermeasure effects still not clearly elucidated. In this study the LBNP/Ergometer effects on female cardiovascular deconditioning and muscle atrophy in 15d head-down bed rest were explored. 22 female university students were recruited as volunteers that participated in the 15d head-down bed rest. They were divided into control group (Con,n=8), LBNP exercise group (LBNP,n=7) and LBNP combined with ergometer exercise group (LBNP+Ergo, n=7). Grade negative pressures of -10,-20,-30,-40mmHg 20 or 55min were used in LBNP exercise. In ergometer exercises the subjects must maintain 60-80% VO2peak of pre-bed rest at pedal speed of about 70cycle/min for 15min and the entire exercise duration was 30min. LBNP were performed at 6th,8th,10th,12th,and 13th day and Ergometer were operated at 4th,5th,7th,9th,11th day during bed rest. Before and after bed rest, cardiovascular tilt test were performed to evaluate orthostatic intolerance, supine cycle ergometer were used to test the cardiopulmonary function, MRI tests were operated to examine the volume variations of leg muscle groups and isokinetic test were given to test the muscle strength and endurance of knee. 40% of female subjects did not pass the tilt table test after bed rest and exercises made no difference. Compared with pre-BR, VO2max and VO2max /body weight, VO2/HRmax, maximal power and duration significantly decreased in CON group and LBNP group. For the ERGO+LBNP group, there were no visible different in the parameters of cardiopulmonary function except that maximal power and duration decreased. Muscle maximal voluntary contraction and muscle (quadriceps, rectus femoris, gastrocnemius and soleus) volume decreasing in non-predominant leg was larger in Con group than in LBNP+Ergo group. It is suggested that LBNP combined with ergometer in some degrees can counteract the cardiovascular and muscle deconditioning

  10. Virts on ergometer in U.S. Lab

    NASA Image and Video Library

    2014-12-27

    ISS042E082884 (12/27/2014) --- Expedition 42 Flight Engineer Terry Virts of NASA straps into the station’s stationary exercise bicycle known as the Cycle Ergometer with Vibration Isolation System (CEVIS). Each crew member spends an average of 2.5 hours a day exercising to combat the negative effects of prolonged weightlessness by maintaining bone and muscle mass and cardiovascular health.

  11. STS-109 PLT Carey on middeck with ergometer

    NASA Image and Video Library

    2002-03-07

    STS109-E-5479 (7 March 2002)-- Astronaut Duane G. Carey, STS-109 pilot, takes a leisurely "spin" on the bicycle ergometer on the mid deck of the Space Shuttle Columbia, while waiting to assist Flight Day 7's assigned space walkers--astronaut James H. Newman and Michael J. Massimino. The extravehicular mobility unit (EMU) space suits of the two can be seen in the background. The image was recorded with a digital still camera.

  12. Mission Specialist Catherine "Cady" Coleman exercises on the bicycle ergometer

    NASA Image and Video Library

    1995-11-05

    STS073-355-003 (20 October - 5 November 1995) --- Doing her version of "Look, Ma, no hands" is astronaut Catherine G. Coleman. The STS-73 mission specialist works out on the bicycle ergometer on the flight deck of the Earth-orbiting Space Shuttle Columbia. Coleman was one of five NASA astronauts who were joined by two guest researchers for 16 days of in-space research in support of the United States Microgravity Laboratory (USML-2) mission.

  13. Physiological responses to 1000-m ergometer time-trial performance in outrigger canoeing.

    PubMed

    Kerr, Rebecca; Spinks, Warwick; Leicht, Anthony; Sinclair, Wade; Woodside, Louise

    2008-09-01

    Graded exercise tests are commonly used to assess peak physiological capacities of athletes. However, unlike time trials, these tests do not provide performance information. The aim of this study was to examine the peak physiological responses of female outrigger canoeists to a 1000-m ergometer time trial and compare the time-trial performance to two graded exercise tests performed at increments of 7.5 W each minute and 15 W each two minutes respectively. 17 trained female outrigger canoeists completed the time trial on an outrigger canoe ergometer with heart rate (HR), stroke rate, power output, and oxygen consumption (VO2) determined every 15 s. The mean (+/- s) time-trial time was 359 +/- 33 s, with a mean power output of 65 +/- 16 W and mean stroke rate of 56 +/- 4 strokes min(-1). Mean values for peak VO2, peak heart rate, and mean heart rate were 3.17 +/- 0.67 litres min(-1), 177 +/- 11 beats min(-1), and 164 +/- 12 beats min(-1) respectively. Compared with the graded exercise tests, the time-trial elicited similar values for peak heart rate, peak power output, peak blood lactate concentration, and peak VO2. As a time trial is sport-specific and can simultaneously quantify sprint performance and peak physiological responses in outrigger canoeing, it is suggested that a time trial be used by coaches for crew selection as it doubles as a reliable performance measure and a protocol for monitoring peak aerobic capacity of female outrigger canoeists.

  14. Experimental heart rate regulation in cycle-ergometer exercises.

    PubMed

    Paradiso, Michele; Pietrosanti, Stefano; Scalzi, Stefano; Tomei, Patrizio; Verrelli, Cristiano Maria

    2013-01-01

    The heart rate can be effectively used as a measure of the exercise intensity during long duration cycle-ergometer exercises: precisely controlling the heart rate (HR) becomes crucial especially for athletes or patients with cardiovascular/obesity problems. The aim of this letter is to experimentally show how the nonlocal and nonswitching nonlinear control that has been recently proposed in the literature for the HR regulation in treadmill exercises can be effectively applied to cycle-ergometer exercises at constant cycling speed. The structure of the involved nonlinear model for the HR dynamics in cycle-ergometer exercises is mathematically inspired by the structure of a recently identified and experimentally validated nonlinear model for the HR dynamics in treadmill exercises: the role played by the treadmill speed is played here by the work load while the zero speed case for the treadmill exercise is here translated into the cycling operation under zero work load. Experimental results not only validate the aforementioned nonlinear model but also demonstrate the effectiveness--in terms of precise HR regulation--of an approach which simply generalizes to the nonlinear framework the classical proportional-integral control design. The possibility of online modifying the HR reference on the basis of the heart rate variability (HRV) is also suggested and experimentally motivated.

  15. The oxidant-antioxidant equilibrium, activities of selected lysosomal enzymes and activity of acute phase protein in peripheral blood of 18-year-old football players after aerobic cycle ergometer test combined with ice-water immersion or recovery at room temperature.

    PubMed

    Sutkowy, Paweł; Woźniak, Alina; Boraczyński, Tomasz; Boraczyński, Michał; Mila-Kierzenkowska, Celestyna

    2017-02-01

    The goal of the study was to evaluate the effect of an aerobic exercise bout followed by ice-water immersion or recovery at room temperature on the redox state, activities of selected lysosomal enzymes and activity of α1-antitrypsin (AAT) in the blood of healthy sportsmen. Eleven amateur football players aged 18 were randomly assigned to two similar 30-min aerobic cycle ergometer tests followed by a recovery at room temperature (20 °C; Experiment 1) or ice-water immersion (3 °C, 5 min; Experiment 2). Peripheral blood was collected three times during both study experiments: before (baseline), as well as 20 and 40 min after the recovery or immersion. The concentrations of thiobarbituric acid reactive substances in blood plasma (plTBARS) and erythrocytes (erTBARS) were measured. The erythrocytic activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were also determined. In the blood serum, the activities of acid phosphatase (AcP), arylsulphatase (ASA), cathepsin D (CTS D) and AAT were evaluated. The activities of AcP, ASA, CTS D and AAT changed similarly during both experiments. The GPx activity decreased 40 min after the exercise/recovery compared to the baseline activity and was lower than 40 min after the exercise/immersion. The exercise followed by the recovery or immersion had no significant effect on the serum lysosomal and AAT activities in the studied men. The exercise/recovery reduced the hydrogen peroxide concentration in the men's erythrocytes, however the exercise/immersion demonstrated the opposite effect. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. The Demise of Skid Row.

    ERIC Educational Resources Information Center

    Siegal, Harvey A.; Inciardi, James A.

    1982-01-01

    Describes the history and evolution of the American skid row; analyzes the changes it has undergone, particularly in the face of urban renewal; and speculates on its future. Includes opinions of the inhabitants of skid row which were obtained from interviews. (MJL)

  17. The Demise of Skid Row.

    ERIC Educational Resources Information Center

    Siegal, Harvey A.; Inciardi, James A.

    1982-01-01

    Describes the history and evolution of the American skid row; analyzes the changes it has undergone, particularly in the face of urban renewal; and speculates on its future. Includes opinions of the inhabitants of skid row which were obtained from interviews. (MJL)

  18. Continuous assistive-passive exercise and cycle ergometer training in sedentary women.

    PubMed

    Martin, D; Kauwell, G P

    1990-08-01

    Continuous assistive-passive exercise (CAPE) is a new exercise modality that has become popular with older females. To evaluate the efficacy of CAPE, 43 sedentary, postmenopausal women (PMW) were randomly divided into three groups: CAPE training (N = 15), cycle ergometer training (N = 14), and control (N = 14). The CAPE training consisted of 10 min bouts on six CAPE tables, twice per week. The cycle ergometer group trained twice per week for 30 min per session, at 70-85% of maximal heart rate. The cycle ergometer and CAPE groups trained for 12 wk, while the control group remained sedentary for the duration of the study. Groups were similar with respect to age, height, weight, girths, skinfolds, and aerobic power (VO2max) upon entering the study (P greater than 0.05). The groups were tested pre- and post-training on the sum of seven body girths (sigma 7G), sum of four skinfolds (sigma 4SF), weight, and VO2max. A 3 d dietary recall was recorded pre and post and analyzed for total caloric intake. Following training, changes in caloric intake, sigma 7G, and sigma 4SF were not significantly different among groups. The cycle group lost 1.1 kg (P less than 0.05) and increased VO2max (l.min-1) by 9.2% (P less than 0.05), while the CAPE group significantly decreased VO2max (P = 0.04). Our results indicate that CAPE does not alter sigma 7G or sigma 4SF in sedentary PMW and that two 30 min sessions of cycle training per week at 70-85% of maximal heart rate can result in moderate but significant increases in VO2max in sedentary PMW.

  19. Working Capacity of Normal Children Tested on a Bicycle Ergometer

    PubMed Central

    Cumming, Gordon R.; Cumming, P. M.

    1963-01-01

    Working capacity defined as that work load performed at a minute pulse rate of 170 was determined in 200 school children aged 6 to 16 and in 40 young adults. Working capacity increased gradually with age and was greater in boys than girls at all ages. The range of normal was large. Working capacities of 11- and 12-year-old Winnipeg children in kg./M./min. were 384 for boys and 300 for girls, these values being 19 and 14% below comparable studies from California and Sweden. Working capacities of Winnipeg student nurses averaged 478 kg./M./min., half the value reported for nurses from Sweden. PMID:14024227

  20. Physical exercises on a bicycle-ergometer and running track to prevent hypodynamia in workers of intellectual labor

    NASA Technical Reports Server (NTRS)

    Vasilyeva, V. V.; Korableva, Y. N.; Trunin, V. V.

    1980-01-01

    A program of exercises was developed and tested, consisting of a 12 minute session on a variable load bicycle ergometer and a 10-11 min. run with brief stretching and resting sessions between. Physical performance capacity was measured before, during, and after the period of the experiment and physical exams conducted. After a 4 month test period involving 30 men, aged 25-35, the program was found to be successful in increasing physical performance capacity. The PWC170 increased an average of 22 percent and maximum oxygen consumption 14 percent. Arterial pressure dropped (120/75 to 114/68), vital capacity of lungs increased by 6 percent, strength of respiratory muscles by 8.8 percent, duration of respiratory delay by 18 percent. Duration of cardiac cycles increased, stress index decreased. Cardiac contraction rate 2 minutes after work on the ergometer decreased from 118 to 102 bt/min.

  1. Reliability and effect of sodium bicarbonate: buffering and 2000-m rowing performance.

    PubMed

    Carr, Amelia J; Slater, Gary J; Gore, Christopher J; Dawson, Brian; Burke, Louise M

    2012-06-01

    The aim of this study was to determine the effect and reliability of acute and chronic sodium bicarbonate ingestion for 2000-m rowing ergometer performance (watts) and blood bicarbonate concentration [HCO3-]. In a crossover study, 7 well-trained rowers performed paired 2000-m rowing ergometer trials under 3 double-blinded conditions: (1) 0.3 grams per kilogram of body mass (g/kg BM) acute bicarbonate; (2) 0.5 g/kg BM daily chronic bicarbonate for 3 d; and (3) calcium carbonate placebo, in semi-counterbalanced order. For 2000-m performance and [HCO3-], we examined differences in effects between conditions via pairwise comparisons, with differences interpreted in relation to the likelihood of exceeding smallest worthwhile change thresholds for each variable. We also calculated the within-subject variation (percent typical error). There were only trivial differences in 2000-m performance between placebo (277 ± 60 W), acute bicarbonate (280 ± 65 W) and chronic bicarbonate (282 ± 65 W); however, [HCO3-] was substantially greater after acute bicarbonate, than with chronic loading and placebo. Typical error for 2000-m mean power was 2.1% (90% confidence interval 1.4 to 4.0%) for acute bicarbonate, 3.6% (2.5 to 7.0%) for chronic bicarbonate, and 1.6% (1.1 to 3.0%) for placebo. Postsupplementation [HCO3-] typical error was 7.3% (5.0 to 14.5%) for acute bicarbonate, 2.9% (2.0 to 5.7%) for chronic bicarbonate and 6.0% (1.4 to 11.9%) for placebo. Performance in 2000-m rowing ergometer trials may not substantially improve after acute or chronic bicarbonate loading. However, performances will be reliable with both acute and chronic bicarbonate loading protocols.

  2. Row effect for R-11 condensation on enhanced tubes

    SciTech Connect

    Webb, R.L.; Murawski, C.G. )

    1990-08-01

    Experimental results of a condensation row effect study on enhanced tubes are presented. A test cell was constructed to condense Refrigerant-11 on the shell side of a vertical bank of five horizontal tubes. Four distinctly different commercially available tubes were tested. The tubes are a 1024-fpm integral fin, the Wolverine Tube-C, Wieland GEWA-SC, and the Tred-D. A modified Turbo-C tube was also tested. Experimental and visual observations are used to understand the row effect due to condensate loading. By plotting the data in the form of the local condensation coefficient versus condensate Reynolds number, the results may be interpreted for any number of tube rows, up to the maximum Reynolds numbers tested. Bundle average condensation coefficients may be established by integrating the h versus Re values over the number of tube rows.

  3. No evidence of expertise-related changes in muscle synergies during rowing.

    PubMed

    Turpin, Nicolas A; Guével, Arnaud; Durand, Sylvain; Hug, François

    2011-12-01

    The purpose of the present study was to determine whether expertise in rowing is driven by a specific structure in muscular coordination. We compared seven experienced rowers and eight untrained (i.e., inexperienced) subjects during rowing on an ergometer. Both surface electromyography activity and mechanical patterns (forces exerted at the handle and the foot-stretcher) were recorded during a high intensity rowing exercise. A non-negative matrix factorization was applied to 23 electromyographic patterns to differentiate muscle synergies. Results showed that expertise was not associated with different dimensionality in the electromyographic data and that three muscle synergies were sufficient to explain the majority of the variance accounted for (i.e., >90% of the total variance) in the two populations. The synergies extracted were similar in the two populations, with identical functional roles. While the temporal organization of the propulsive synergies was very similar, slight differences were found in the composition of the muscle synergies (muscle synergy vectors) between the two populations. The results suggests that rowing expertise would not require the development of novel muscle synergies but would imply intrinsic synergies already used in different behaviors. Performance in rowing is more probably linked to adjustments in the mechanical output of the muscle synergies rather than to differences in the shape and timing of their activations. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Validation of a dual-cycle ergometer for exercise during 100 percent oxygen prebreathing

    NASA Technical Reports Server (NTRS)

    Wiegman, Janet F.; Ohlhausen, John H.; Webb, James T.; Pilmanis, Andrew A.

    1992-01-01

    A study has been designed to determine if exercise, while prebreathing 100 percent oxygen prior to decompression, can reduce the current resting-prebreathe time requirements for extravehicular activity and high altitude reconnaissance flight. For that study, a suitable exercise mode was required. Design considerations included space limitations, cost, pressure suit compatibility, ease and maintenance of calibration, accuracy of work output, and assurance that no significant mechanical advantage or disadvantage would be introduced into the system. In addition, the exercise device must enhance denitrogenation by incorporation of both upper and lower body musculature at high levels of oxygen consumption. The purpose of this paper is to describe the specially constructed, dual-cycle ergometer developed for simultaneous arm and leg exercise during prebreathing, and to compare maximal oxygen uptake obtained on the device to that obtained during leg-only cycle ergometry and treadmill testing. Results demonstrate the suitability of the dual-cycle ergometer as an appropriate tool for exercise research during 100 percent oxygen prebreathing.

  5. Validation of a dual-cycle ergometer for exercise during 100 percent oxygen prebreathing

    NASA Technical Reports Server (NTRS)

    Wiegman, Janet F.; Ohlhausen, John H.; Webb, James T.; Pilmanis, Andrew A.

    1992-01-01

    A study has been designed to determine if exercise, while prebreathing 100 percent oxygen prior to decompression, can reduce the current resting-prebreathe time requirements for extravehicular activity and high altitude reconnaissance flight. For that study, a suitable exercise mode was required. Design considerations included space limitations, cost, pressure suit compatibility, ease and maintenance of calibration, accuracy of work output, and assurance that no significant mechanical advantage or disadvantage would be introduced into the system. In addition, the exercise device must enhance denitrogenation by incorporation of both upper and lower body musculature at high levels of oxygen consumption. The purpose of this paper is to describe the specially constructed, dual-cycle ergometer developed for simultaneous arm and leg exercise during prebreathing, and to compare maximal oxygen uptake obtained on the device to that obtained during leg-only cycle ergometry and treadmill testing. Results demonstrate the suitability of the dual-cycle ergometer as an appropriate tool for exercise research during 100 percent oxygen prebreathing.

  6. Alternative Physical Therapy Protocol Using a Cycle Ergometer During Hospital Rehabilitation of Coronary Artery Bypass Grafting: a Clinical Trial

    PubMed Central

    Trevisan, Margarete Diprat; Lopes, Diene Gomes Colvara; de Mello, Renato Gorga Bandeira; Macagnan, Fabrício Edler; Kessler, Adriana

    2015-01-01

    OBJECTIVE To compare the efficacy of a cycle ergometer-based exercise program to a standard protocol on the increment of the maximum distance walked during the six-minute walk test in the postoperative rehabilitation of patients submitted to coronary artery bypass grafting. METHODS A controlled clinical trial pilot, blinded to the outcome, enrolled subjects who underwent coronary artery bypass grafting in a hospital from Southern Brazil. Subjects were designated for the standard physical rehabilitation protocol or to an alternative cycle ergometer-based protocol through simple random sampling. The primary outcome was the difference in the maximum distance walked in the six-minute walk test before and after the allocated intervention. RESULTS Twenty-four patients were included in the analysis, 10 in the standard protocol and 14 in the alternative protocol group. There was an increment in the maximum distance walked in both groups, and borderline superiority in the intervention group comparing to the control group (312.2 vs. 249.7; P=0.06). CONCLUSION There was an increase in the maximum distance walked in the alternative protocol compared to the standard protocol. Thus, it is postulated that the use of a cycle ergometer can be included in physical rehabilitation in the hospital phase of postoperative coronary artery bypass grafting. However, randomized studies with larger sample size should be conducted to assess the significance of these findings. PMID:26934400

  7. Comparison of VO[subscript 2] Maximum Obtained from 20 m Shuttle Run and Cycle Ergometer in Children with and without Developmental Coordination Disorder

    ERIC Educational Resources Information Center

    Cairney, John; Hay, John; Veldhuizen, Scott; Faught, Brent

    2010-01-01

    Oxygen consumption at peak physical exertion (VO[subscript 2] maximum) is the most widely used indicator of cardiorespiratory fitness. The purpose of this study was to compare two protocols for its estimation, cycle ergometer testing and the 20 m shuttle run, among children with and without probable developmental coordination disorder (pDCD). The…

  8. Comparison of VO[subscript 2] Maximum Obtained from 20 m Shuttle Run and Cycle Ergometer in Children with and without Developmental Coordination Disorder

    ERIC Educational Resources Information Center

    Cairney, John; Hay, John; Veldhuizen, Scott; Faught, Brent

    2010-01-01

    Oxygen consumption at peak physical exertion (VO[subscript 2] maximum) is the most widely used indicator of cardiorespiratory fitness. The purpose of this study was to compare two protocols for its estimation, cycle ergometer testing and the 20 m shuttle run, among children with and without probable developmental coordination disorder (pDCD). The…

  9. Gross efficiency and energy expenditure in kayak ergometer exercise.

    PubMed

    Gomes, B B; Mourão, L; Massart, A; Figueiredo, P; Vilas-Boas, J P; Santos, A M C; Fernandes, R J

    2012-08-01

    We purposed to study energy expenditure, power output and gross efficiency during kayak ergometer exercise in 12 elite sprint kayakers. 6 males (age 24.2±4.8 years, height 180.4±4.8 cm, body mass 79.7±8.5 kg) and 6 females (age 24.3±4.5 years, height 164.5±3.9 cm, body mass 65.4±3.5 kg), performed an incremental intermittent protocol on kayak ergometer with VO2 and blood lactate concentration assessment, a non-linear increase between power output and energy expenditure being observed. Paddling power output, energy expenditure and gross efficiency corresponding to VO2max averaged 199.92±50.41 W, 75.27±6.30 ml.kg - 1.min - 1, and 10.10±1.08%. Male kayakers presented higher VO2max, power output and gross efficiency at the VO2max, and lower heart rate and maximal lactate concentration than females, but no differences were found between genders regarding energy expenditure at VO2max. Aerobic and anaerobic components of energy expenditure evidenced a significant contribution of anaerobic energy sources in sprint kayak performance. Results also suggested the dependence of the gross efficiency on the changes in the amount of the aerobic and anaerobic contributions, at heavy and severe intensities. The inter-individual variance of the relationship between energy expenditure and the corresponding paddling power output revealed a relevant tracking for females (FDγ=0.73±0.06), conversely to the male group (FDγ=0.27±0.08), supporting that some male kayakers are more skilled in some paddling intensities than others.

  10. Length to diameter ratio and row number effects in short pin fin heat transfer

    NASA Technical Reports Server (NTRS)

    Brigham, B. A.; Vanfossen, G. J.

    1982-01-01

    The relative effects of pin length to diameter ratio and of pin row geometry on the heat transfer from pin fins, was determined. Array averaged heat transfer coefficients on pin and endwall surfaces were measured for two configurations of staggered arrays of short pin fins (length to diameter ratio of 4). One configuration contained eight streamwise rows of pins, while the other contained only four rows. Results showed that both the 8-row and the 4-row configurations for an L sub p/D of 4, exhibit higher heat transfer than in similar tests on shorter pin fns (L sub p/D of 1/2 and 2). It was also found that for this L sub p/D ratio, the array averaged heat transfer was slightly higher with eight rows of staggered pins than with only four rows.

  11. Length to diameter ratio and row number effects in short pin fin heat transfer

    NASA Technical Reports Server (NTRS)

    Brigham, B. A.; Vanfossen, G. J.

    1984-01-01

    The relative effects of pin length to diameter ratio and of pin row geometry on the heat transfer from pin fins, was determined. Array averaged heat transfer coefficients on pin and endwall surfaces were measured for two configurations of staggered arrays of short pin fins (length to diameter ratio of 4). One configuration contained eight streamwise rows of pins, while the other contained only four rows. Results showed that both the 8-row and the 4-row configurations for an L sub p/D of 4, exhibit higher heat transfer than in similar tests on shorter pin fins (L sub p/D of 1/2 and 2). It was also found that for this L sub p/D ratio, the array averaged heat transfer was slightly higher with eight rows of staggered pins than with only four rows. Previously announced in STAR as N83-14431

  12. The effect of an intermittent, high-intensity warm-up on supramaximal kayak ergometer performance.

    PubMed

    Bishop, David; Bonetti, Darrel; Spencer, Matthew

    2003-01-01

    It has previously been shown that the metabolic acidaemia induced by a continuous warm-up at the 'lactate threshold' is associated with a reduced accumulated oxygen deficit and decreased supramaximal performance. The aim of this study was to determine if an intermittent, high-intensity warm-up could increase oxygen uptake (VO2) without reducing the accumulated oxygen deficit, and thus improve supramaximal performance. Seven male 500 m kayak paddlers, who had represented their state, volunteered for this study. Each performed a graded exercise test to determine VO2max and threshold parameters. On subsequent days and in a random, counterbalanced order, the participants then performed a continuous or intermittent, high-intensity warm-up followed by a 2 min, all-out kayak ergometer test. The continuous warm-up consisted of 15 min of exercise at approximately 65% VO2max. The intermittent, high-intensity warm-up was similar, except that the last 5 min was replaced with five 10 s sprints at 200% VO2max, separated by 50 s of recovery at approximately 55% VO2max. Significantly greater (P < 0.05) peak power (intermittent vs continuous: 629 +/- 199 vs 601 +/- 204 W) and average power (intermittent vs continuous: 328 +/- 39.0 vs 321 +/- 42.4 W) were recorded after the intermittent warm-up. There was no significant difference between conditions for peak VO2, total VO2 or the accumulated oxygen deficit. The results of this study indicate that 2 min all-out kayak ergometer performance is significantly better after an intermittent rather than a continuous warm-up.

  13. Alcoholic Women on Skid Row.

    ERIC Educational Resources Information Center

    Anderson, Sandra C.

    1987-01-01

    Examined women (N=20) who were receiving alcoholism treatment in the skid-row area of Portland, Oregon. Women had histories of problem drinking and extensive treatment for alcoholism. Most had been married and had children. Despite transiency, the majority maintained contact with friends and relatives. Compared these women to New York City's…

  14. A physiological and biomechanical comparison of over-ground, treadmill and ergometer wheelchair propulsion.

    PubMed

    Mason, Barry; Lenton, John; Leicht, Christof; Goosey-Tolfrey, Victoria

    2014-01-01

    The purpose of the study was to determine which laboratory-based modality provides the most valid physiological and biomechanical representation of over-ground sports wheelchair propulsion. Fifteen able-bodied participants with previous experience of wheelchair propulsion performed a 3-minute exercise trial at three speeds (4, 6 and 8 km ∙ h(-1)) in three testing modalities over separate sessions: (i) over-ground propulsion on a wooden sprung surface; (ii) wheelchair ergometer propulsion; (iii) treadmill propulsion at four different gradients (0%, 0.7%, 1.0% and 1,3%). A 0.7% treadmill gradient was shown to best reflect the oxygen uptake (7.3 to 9.1% coefficient of variation (CV)) and heart rate responses (4.9 to 6.4% CV) of over-ground propulsion at 4 and 6 km ∙ h(-1). A 1.0% treadmill gradient provided a more valid representation of oxygen uptake during over-ground propulsion at 8 km ∙ h(-1) (8.6% CV). Physiological demand was significantly underestimated in the 0% gradient and overestimated in the 1.3% gradient and wheelchair ergometer trials compared to over-ground trials (P<0.05). No laboratory-based modality provided a valid representation of the forces applied during OG (≥ 18.4% CV). To conclude, a 0.7% treadmill gradient is recommended to replicate over-ground wheelchair propulsion at lower speeds (4 and 6 km ∙ h(-1)) whereas a 1.0% gradient may be more suitable at 8 km ∙ h(-1).

  15. Methods comparison: assessing agreement of physiological parameters obtained from exercise on two different cycle ergometers.

    PubMed

    Siedlik, Jake A; Harrison, Grant; Brigman, Robert; Graham, Zachary A; Weir, Joseph P; Gallagher, Philip M; Vardiman, John P

    2015-04-01

    The purpose of this study was to determine the agreement of physiological parameters measured during exercise testing on 2 devices at established power outputs (POs). Ten trained male cyclists were recruited. The devices used for comparison were the Lode stationary bicycle ergometer (SBE) (Lode Excalibur) and the PowerTap Pro+ (BPT) (Saris Cycling Group) mobile ergometer. The physiological parameters recorded at established PO (50, 100, 150, 200, 250 W) were heart rate (HR), oxygen consumption ((Equation is included in full-text article.)), pulmonary ventilation (VE), blood lactate, and ratings of perceived exertion (RPE). Subjects were randomized once to the SBE and 3 times to a bicycle equipped with a BPT. After 15 minutes of unloaded pedaling, the trial began with 5 minutes of cycling at 50 W. Intensity increased by 50 W every 5 minutes up to 250 W. Physiological measures were recorded at each PO. Bland-Altman plots were constructed including computation of the ratio of half the range of limits of agreement and the mean of the pairwise means along with bivariate regression calculations for analysis of the linear association between device measurements. Moderate to good agreement was found for HR with agreement improving as PO increased. Comparisons of (Equation is included in full-text article.)found agreement increased as the PO increased. VE, RPE, and lactate did not consistently provide similar measures across trials. The level of agreement between HR and (Equation is included in full-text article.)when comparing the SBE and BPT suggests that the PowerTap Pro+ is a sufficient tool for estimating PO and associated physiological parameters in the field.

  16. Mechanical performance of aquatic rowing and flying.

    PubMed Central

    Walker, J A; Westneat, M W

    2000-01-01

    Aquatic flight, performed by rowing or flapping fins, wings or limbs, is a primary locomotor mechanism for many animals. We used a computer simulation to compare the mechanical performance of rowing and flapping appendages across a range of speeds. Flapping appendages proved to be more mechanically efficient than rowing appendages at all swimming speeds, suggesting that animals that frequently engage in locomotor behaviours that require energy conservation should employ a flapping stroke. The lower efficiency of rowing appendages across all speeds begs the question of why rowing occurs at all. One answer lies in the ability of rowing fins to generate more thrust than flapping fins during the power stroke. Large forces are necessary for manoeuvring behaviours such as accelerations, turning and braking, which suggests that rowing should be found in slow-swimming animals that frequently manoeuvre. The predictions of the model are supported by observed patterns of behavioural variation among rowing and flapping vertebrates. PMID:11052539

  17. COPD patients' oxygen uptake and heart rate on-kinetics at cycle-ergometer: correlation with their predictors of severity.

    PubMed

    Pessoa, Bruna V; Beltrame, Thomas; Di Lorenzo, Valéria A Pires; Catai, Aparecida M; Borghi-Silva, Audrey; Jamami, Mauricio

    2013-01-01

    To assess whether there is a correlation between oxygen uptake (VO2) and heart rate (HR) on-kinetics in the constant-load cycle-ergometer test (CLT) and the BODE index and its isolated variables in patients with chronic obstructive pulmonary disease (COPD). Fourteen male patients between 55 and 78 years of age with moderate to severe COPD were evaluated. Each patient underwent spirometry, the six-minute walk test (6MWT), the cycle-ergometer incremental test (IT) and CLT on alternate days. The exhaled gases were collected, and the VO2 and HR on-kinetics were analyzed. The BODE index was calculated. It was noted that the VO2 tau (τ) and mean response time (MRT) were significantly higher than HR τ and MRT. Moderate and strong correlations between τ and MRT of the VO2 and HR and the BODE index was noted (r=0.75 and r=0.78; r=0.62 and r=0.63, respectively), and there were correlations between the VO2 τ and MRT and the forced expiratory volume in one second (FEV1) (r=-0.60; r=-0.53) and the distance traveled at 6MWT (DT-6MWT) (r=-0.61; r=-0.44) and DT-6MWT % predicted (r=-0.62; r=-0.46). The HR τ and MRT were correlated with DT-6MWT (r=-0.59; r=-0.58) and DT-6MWT % predicted (r=-0.62; r=-0.62). The slowing of cycle-ergometer VO2, and especially of HR on-kinetics, may be key markers of disease severity. Furthermore, airflow obstruction and reduced exercise capacity are associated with the slowing of patients' VO2 and HR on-kinetics.

  18. On heart rate regulation in cycle-ergometer exercise.

    PubMed

    Argha, Ahmadreza; Su, Steven W; Lee, Sangwon; Nguyen, Hung; Celler, Branko G

    2014-01-01

    In this paper, we have focused on the issue of regulating the human heart rate (HR) to a predefined reference trajectory, especially for cycle-ergometer exercise used for training or rehabilitation. As measuring HR is relatively easy compared to exercise intensity, it has been used in the wide range of training programs. The aim of this paper is to develop a non-model-based control strategy using proportional, integral and derivative (PID) controller/relay controller to regulate the HR to track a desired trajectory. In the case of using PID controller, the controller output signal is interpreted as a voice or auditory command, referred to as biofeedback, which can be heard by the exercising subject as a part of the control-loop. Alternatively, the relay controller output signals can be converted to some special words which can be recognised by the exerciser. However, in both cases, to effectively communicate to the user a change in exercise intensity, the timing of this feedback signal relative to the positions of the pedals becomes quite critical. A feedback signal delivered when the pedals are not in a suitable position to efficiently exert force may be ineffective and may lead to a cognitive disengagement of the user form the feedback controller. In this paper we examine the need and the consequence of synchronising the delivery of the feedback signal with an optimal and user specific placement of the pedal.

  19. Combined inhalation of beta2 -agonists improves swim ergometer sprint performance but not high-intensity swim performance.

    PubMed

    Kalsen, A; Hostrup, M; Bangsbo, J; Backer, V

    2014-10-01

    There is a high prevalence of asthma and airway hyperresponsiveness (AHR) in elite athletes, which leads to a major use of beta2 -agonists. In a randomized double-blinded crossover study, we investigated the effects of combined inhalation of beta2 -agonists (salbutamol, formoterol, and salmeterol), in permitted doses within the World Anti-Doping Agency 2013 prohibited list, in elite swimmers with (AHR, n = 13) or without (non-AHR, n = 17) AHR. Maximal voluntary isometric contraction of m. quadriceps (MVC), sprint performance on a swim ergometer and performance in an exhaustive swim test at 110% of VO2max were determined. Venous plasma interleukin-6 (IL-6) and interleukin-8 (IL-8) were measured post-exercise. No improvement was observed in the exhaustive swim test, but swim ergometer sprint time was improved (P < 0.05) in both groups from 57 ± 1.7 to 56 ± 1.8 s in AHR and 58.3 ± 1 to 57.4 ± 1 s in non-AHR. MVC and post-exercise plasma IL-6 increased (P < 0.05) with beta2 -agonists in both groups, whereas IL-8 only increased in AHR. In summary, inhalation of beta2 -agonists, in permitted doses, did not improve swim performance in elite swimmers. However, swim ergometer sprint performance and MVC were increased, which should be considered when making future anti-doping regulations.

  20. Astronaut Frank Culbertson on the ergometer in STS-51 Discovery's middeck

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Astronaut Frank L. Culbertson Jr., STS-51 mission commander, appears to be enjoying a session on the ergometer, temporarily deployed on Discovery's middeck. There are sleep restraints attached to the wall behind him and a bag floating next to him.

  1. Flight and Test-stand Investigation of High-performance Fuels in Modified Double-row Radial Air-cooled Engines III: Knock-limited Performance of 33-R as Compared with a Triptane Blend and 28-R in Flight

    NASA Technical Reports Server (NTRS)

    Blackman, Calvin C.; White, H. Jack

    1945-01-01

    A comparison has been made in flight of the antiknock characteristics of 33-R fuel with that of 28-R and a triptane blent. The knock-limited performance of the three fuels - 33-R, a blend of 80 percent 28-R plus 20 percent triptane (leaded to 4.5 ml TEL/gal), and 28-R - was investigated in two modified 14-cylinder double-row radial air-cooled engines. Tests were conducted on the engines as installed in the left inboard nacelle of an airplane. A carburetor-air temperature of approximately 85 deg F was maintained. The conditions covered at an engine speed of 2250 rpm were high and low blower ratios and spark advances of 25 deg and 32 deg B.T.C. For an engine speed of 1800 rpm only the high-blower condition was investigated for both 25 deg and 32 deg spark advances. For the conditions investigated the difference between 33-R and the triptane blend was found to be slight; the performance of 33-R fuel, however, was slightly higher than that of the triptane blend in the lean region. The knock-limited power obtained with the 33-R fuel was from 14 to 28 percent higher than that of the 28-R fuel for the entire range of test conditions; the greatest improvement was shown in the lean region.

  2. An analysis of the pacing strategy adopted by elite competitors in 2000 m rowing

    PubMed Central

    Garland, S

    2005-01-01

    Objectives: To determine the pacing strategies adopted by elite rowers in championship 2000 m races. Methods: Split times were obtained for each boat in every heavyweight race of the Olympic Games in 2000 and World Championships in 2001 and 2002, and the top 170 competitors in the British Indoor Rowing Championships in 2001 and 2002. Data were only included in subsequent analysis if there was good evidence that the athlete or crew completed the race in the fastest possible time. The remaining data were grouped to determine if there were different strategies adopted for on-water versus ergometer trials, "winners" versus "losers", and men versus women. Results: Of the 1612 on-water race profiles considered, 948 fitted the inclusion criteria. There were no differences in pacing profile between winners and losers, and men and women, although on-water and ergometry trials showed a competitively meaningful significant difference over the first 500 m sector. The average profile showed that rowers performed the first 500 m of the race faster than subsequent sectors—that is, at a speed of 103.3% of the average speed for the whole race, with subsequent sectors rowed at 99.0%, 98.3%, and 99.7% of average speed for on-water rowing, and 101.5%, 99.8%, 99.0%, and 99.7% for ergometry. Conclusions: These data indicate that all athletes or crews adopted a similar fast start strategy regardless of finishing position or sex, although the exact pace profile was dependent on rowing mode. This strategy should be considered by participants in 2000 m rowing competitions. PMID:15618339

  3. Blood lactate and hormonal responses to prototype flywheel ergometer workouts.

    PubMed

    Caruso, John F; Coday, Michael A; Monda, Julie K; Ramey, Elizabeth S; Hastings, Lori P; Vingren, Jakob L; Potter, William T; Kraemer, William J; Wickel, Eric E

    2010-03-01

    The purpose of the study was to compare blood lactate and hormonal responses with flywheel ergometer (FERG) leg presses for preliminary assessment of workouts best suited for future in-flight resistance exercise. Comprised of 10 repetition sets, the workouts entailed 3 sets of concentric and eccentric (CE3) actions, or concentric-only actions done for 3 (CO3) or 6 (CO6) sets. Methods employed included assessment of blood lactate concentrations ([BLa-]) before and 5 minutes postexercise. Venous blood was also collected before and at 1 and 30 minutes postexercise to assess growth hormone, testosterone, cortisol concentrations ([GH], [T], [C]) and [T/C] ratios. [BLa-] were compared with 2 (time) x 3 (workout) analysis of variance. Hormones were assessed with 2 (gender) x 3 (time) x 3 (workout) analysis of covariances. Results showed [BLa-] had a time effect. Growth hormone concentration showed gender x workout, gender x time, and workout x time interactions, whereas [T] had a 3-way interaction. [C] had gender, time, and workout effects. [T/C] yielded a gender x time interaction. It was concluded that, because CO6 and CE3 yielded similar anabolic hormonal data but the latter had a lower [C] 30 minutes postexercise, CE3 served as the best workout. Although the FERG was originally designed for microgravity, the effort put forth by current subjects was like that for workouts aimed at greater athletic performance and conditioning. Practical applications suggest that eccentric actions should be used for FERG workouts geared toward muscle mass and strength improvement.

  4. Modelling the deflection of rowing oar shafts.

    PubMed

    Laschowski, Brock; Hopkins, Cameron C; de Bruyn, John R; Nolte, Volker

    2017-03-01

    The deflection of rowing oar shafts subjected to a static load was investigated. Two sets of sculling oars of different design stiffness were tested at three different lengths from 2.66 to 2.70 m. Loads up to 201 N were applied to the blade end of the oar shafts, and deflections were measured at six positions along the length of the shafts. The experimental results were compared with theoretical predictions obtained by modelling the oar shafts as homogenous end-loaded cantilever beams. The results show that the oar shafts are not uniform, in contradiction to the assumed model, but rather are most compliant near the sleeves and up to 80% stiffer towards the blades. The effect of oar shaft stiffness and length on the deflection angle at the blade end of the oar shaft was at most 1.18 ± 0.01°. The measured variation of stiffness along the shaft has implications for boat propulsion and rowing performance.

  5. Effects of isolated cycle ergometer training on patients with moderate-to-severe chronic obstructive pulmonary disease.

    PubMed

    Pitta, F; Brunetto, A F; Padovani, C R; Godoy, I

    2004-01-01

    Pulmonary rehabilitation (PR) programs are beneficial to patients with chronic obstructive pulmonary disease (COPD), and lower-extremity training is considered a fundamental component of PR. Nevertheless, the isolated effects of each PR component are not well established. We aimed to evaluate the effects of a cycle ergometry exercise protocol as the only intervention in a group of COPD patients, and to compare these results with a control group. 25 moderate-to-severe COPD patients were evaluated regarding pulmonary function, respiratory muscle strength, exercise capacity, quality of life and body composition. Patients were allocated to one of two groups: (a) the trained group (TG; n = 13; 6 men) was submitted to a protocol of 24 exercise sessions on a cycle ergometer, with training intensity initially set at a heart rate (HR) close to 80% of maximal HR achieved in a maximal test, and load increase based on dyspnea scores, and (b) the control group (CG; n = 12; 6 men) with no intervention during the protocol period. TG showed within-group significant improvements in endurance cycling time, 6-min walking distance test, maximal inspiratory pressure and in the domain 'dyspnea' related to quality of life. Despite the within-group changes, no between-group significant differences were observed. In COPD patients, the results of isolated low-to-moderate intensity cycle ergometer training are not comparable to effects of multimodality and high-intensity training programs.

  6. A comparison of lactate concentration in plasma collected from the toe, ear, and fingertip after a simulated rowing exercise

    PubMed Central

    Forsyth, J; Farrally, M

    2000-01-01

    Objective—To examine the validity of using blood taken from the toe for the assessment of plasma lactate concentration in rowers. To achieve this, values were compared with those taken from the fingertip and earlobe. Methods—Nine subjects exercised at two separate submaximum workloads on the Concept II rowing ergometer. The loads, each lasting four minutes, elicited mean (SD) heart rate responses of 160.1 (8.5) and 180.1 (5.7) beats/min, which corresponded to 76.4 (6.1)% and 91.9 (4.7)% of the estimated heart rate maximum of the subjects. Blood was simultaneously removed after the cessation of exercise by three experimenters and was analysed for plasma lactate concentration. Results—At 76.4% of estimated heart rate maximum, the mean (SD) plasma lactate concentrations sampled from the fingertip, toe, and earlobe were 6.36 (1.58), 5.81 (1.11), and 5.29 (1.24) mmol/l respectively. At 91.9% of estimated heart rate maximum, respective values were 8.81 (2.30), 8.53 (1.37), and 8.41 (2.35) mmol/l. No significant differences (p>0.05) were found between any of the sites at either work intensity. Conclusions—The toe may offer a practical alternative for assessing the concentration of lactate during rowing, having the advantage that repeated blood samples can be removed without interruption of the rowing action. Key Words: blood sampling; lactate; ergometer; rowing PMID:10690448

  7. Variability of prediction of maximal oxygen concumption on the cycle ergometer using standard equations

    NASA Technical Reports Server (NTRS)

    Greenisen, Michael C.; Fortney, Suzanne M.; Lee, Stuart M. C.; Moore, Alan D.; Barrows, Linda H.

    1993-01-01

    Several investigations within the Exercise Countermeasures Project at the NASA Johnson Space Center focused on the assessment of maximum oxygen consumption (VO2(sub max)) within the Astronaut Corps pre- and postspace flight. Investigations during the Apollo era suggested that there was a significant decrease in postflight VO2(sub max) when compared to preflight values, and current studies have documented that this trend continues in the Space Shuttle era. It is generally accepted and was confirmed in our laboratory that VO2(sub max) can be predicted from submaximal measures taken during graded exercise tests on the cycle ergometer with respect to populations. However, previous work had not examined the effect of day-to-day variations in the physiologic responses that might alter these predictions for individuals. Stability of individual submaximal data over serial tests is important so that predicted changes in VO2(sub max) are reflective of actual VO2(sub max) changes. Therefore, the purpose of this investigation was to determine which of the accepted equations to predict VO2(sub max) would be less affected by normal daily physiologic changes.

  8. [Psychological and physiological effects of a 5-week ergometer training in healthy young men (author's transl)].

    PubMed

    Myrtek, M; Villinger, U

    1976-09-24

    40 healthy male students were randomly assigned to either the exercise or control group. The latter was asked not to alter their common physical activity while the exercise group trained three times weekly on the bicycle ergometer for 15 minutes with a constant heart rate of 140bpm. At the beginning and after five weeks physiological data comprising cardiovascular and pulmonary responses at rest and under submaximal ergometric exercise were assessed. Additional data included psychological achievement tests, self reports of personality dimensions and frequency of physical complaints. Results indicated a marked increase in physical fitness for the training group improving the work load from 158 watt to 197 watt at constant heart rate. At rest and especially at submaximal work load there was an improvement of the economy of the cardiovascular and respiratory system. Contrary to these findings there were no changes or impairment in the psychological achievement tests, measuring concentration. Compared with the control group self reports of personality dimensions did not change except for a tendency to more extrovert behavior in the exercise group. Unexpectedly, the frequency of physical complaints did not decrease. The reason for this discrepancy is discussed.

  9. STS-42 Commander Grabe uses DTO 653 MK1 Rowing Machine on OV-103's middeck

    NASA Image and Video Library

    1992-01-30

    STS042-05-037 (30 Jan 1992) --- Astronaut Ronald J. Grabe, STS-42 commander, exercises using MK1 Rowing Machine on the middeck of Discovery, Orbiter Vehicle (OV) 103. Grabe is using the exercise device as part of Development Test Objective (DTO) 653, Evaluation of MK1 Rowing Machine. The forward lockers appear at Grabe's right and the sleep station behind him.

  10. STS-42 Commander Grabe uses DTO 653 MK1 Rowing Machine on OV-103's middeck

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-42 Commander Ronald J. Grabe exercises using MK1 Rowing Machine on the middeck of Discovery, Orbiter Vehicle (OV) 103. Grabe is using the exercise device as part of Development Test Objective (DTO) 653, Evaluation of MK1 Rowing Machine. The forward lockers appear at Grabe's right and the sleep station behind him.

  11. A macro-driven Excel template for determining the anaerobic capacity using an air-braked ergometer.

    PubMed

    Finn, J P; Sainsbury, D A; Withers, R T

    1996-08-01

    This paper describes a microcomputer system for automating the process of data collection, calculation and display of anaerobic capacity tests on an air-braked ergometer. The use of the spreadsheet Excel and associated 'Dalog' program represents an advance on current software which estimates the anaerobic capacity from work performed alone. Numerous calculations are required when air-braked, rather than friction-braked erogometers are used. Each 1 s power output collected during an all-out sprint on the ergometer is corrected against the criterion of a dynamic calibration rig and adjusted for differences in barometric pressure, ambient temperature and humidity. The Excel template features a series of macros invoked by buttons imbedded in the spreadsheet. Their selection displays various dialogue boxes which request input related to the calculation of oxygen deficit and related variables. Selecting the final macro prints a summary table and charts which include: power output, fatigue index, mechanical work performed, % aerobic contribution to work, oxygen demand, oxygen consumption and anaerobic capacity as determined by the maximal accumulated oxygen deficit.

  12. A Cycle Ergometer Exercise Program Improves Exercise Capacity and Inspiratory Muscle Function in Hospitalized Patients Awaiting Heart Transplantation: a Pilot Study

    PubMed Central

    Forestieri, Patrícia; Guizilini, Solange; Peres, Monique; Bublitz, Caroline; Bolzan, Douglas W.; Rocco, Isadora S.; Santos, Vinícius B.; Moreira, Rita Simone L.; Breda, João R.; de Almeida, Dirceu R.; Carvalho, Antonio Carlos de C.; Arena, Ross; Gomes, Walter J.

    2016-01-01

    Objective The purpose of this study was to evaluate the effect of a cycle ergometer exercise program on exercise capacity and inspiratory muscle function in hospitalized patients with heart failure awaiting heart transplantation with intravenous inotropic support. Methods Patients awaiting heart transplantation were randomized and allocated prospectively into two groups: 1) Control Group (n=11) - conventional protocol; and 2) Intervention Group (n=7) - stationary cycle ergometer exercise training. Functional capacity was measured by the six-minute walk test and inspiratory muscle strength assessed by manovacuometry before and after the exercise protocols. Results Both groups demonstrated an increase in six-minute walk test distance after the experimental procedure compared to baseline; however, only the intervention group had a significant increase (P=0.08 and P=0.001 for the control and intervention groups, respectively). Intergroup comparison revealed a greater increase in the intervention group compared to the control (P<0.001). Regarding the inspiratory muscle strength evaluation, the intragroup analysis demonstrated increased strength after the protocols compared to baseline for both groups; statistical significance was only demonstrated for the intervention group, though (P=0.22 and P<0.01, respectively). Intergroup comparison showed a significant increase in the intervention group compared to the control (P<0.01). Conclusion Stationary cycle ergometer exercise training shows positive results on exercise capacity and inspiratory muscle strength in patients with heart failure awaiting cardiac transplantation while on intravenous inotropic support. PMID:27982348

  13. Changes of heart rate variability and prefrontal oxygenation during Tai Chi practice versus arm ergometer cycling.

    PubMed

    Lu, Xi; Hui-Chan, Christina Wan-Ying; Tsang, William Wai-Nam

    2016-11-01

    [Purpose] Exercise has been shown to improve cardiovascular fitness and cognitive function. Whether the inclusion of mind over exercise would increase parasympathetic control of the heart and brain activities more than general exercise at a similar intensity is not known. The aim of this study was to compare the effects of Tai Chi (mind-body exercise) versus arm ergometer cycling (body-focused exercise) on the heart rate variability and prefrontal oxygenation level. [Subjects and Methods] A Tai Chi master was invited to perform Tai Chi and arm ergometer cycling with similar exercise intensity on two separate days. Heart rate variability and prefrontal oxyhemoglobin levels were measured continuously by a RR recorder and near-infrared spectroscopy, respectively. [Results] During Tai Chi exercise, spectral analysis of heart rate variability demonstrated a higher high-frequency power as well as a lower low-frequency/high-frequency ratio than during ergometer cycling, suggesting increased parasympathetic and decreased sympathetic control of the heart. Also, prefrontal oxyhemoglobin and total hemoglobin levels were higher than those during arm ergometer exercise. [Conclusion] These findings suggest that increased parasympathetic control of the heart and prefrontal activities may be associated with Tai Chi practice. Having a "mind" component in Tai Chi could be more beneficial for older adults' cardiac health and cognitive function than body-focused ergometer cycling.

  14. Changes of heart rate variability and prefrontal oxygenation during Tai Chi practice versus arm ergometer cycling

    PubMed Central

    Lu, Xi; Hui-Chan, Christina Wan-Ying; Tsang, William Wai-Nam

    2016-01-01

    [Purpose] Exercise has been shown to improve cardiovascular fitness and cognitive function. Whether the inclusion of mind over exercise would increase parasympathetic control of the heart and brain activities more than general exercise at a similar intensity is not known. The aim of this study was to compare the effects of Tai Chi (mind-body exercise) versus arm ergometer cycling (body-focused exercise) on the heart rate variability and prefrontal oxygenation level. [Subjects and Methods] A Tai Chi master was invited to perform Tai Chi and arm ergometer cycling with similar exercise intensity on two separate days. Heart rate variability and prefrontal oxyhemoglobin levels were measured continuously by a RR recorder and near-infrared spectroscopy, respectively. [Results] During Tai Chi exercise, spectral analysis of heart rate variability demonstrated a higher high-frequency power as well as a lower low-frequency/high-frequency ratio than during ergometer cycling, suggesting increased parasympathetic and decreased sympathetic control of the heart. Also, prefrontal oxyhemoglobin and total hemoglobin levels were higher than those during arm ergometer exercise. [Conclusion] These findings suggest that increased parasympathetic control of the heart and prefrontal activities may be associated with Tai Chi practice. Having a “mind” component in Tai Chi could be more beneficial for older adults’ cardiac health and cognitive function than body-focused ergometer cycling. PMID:27942158

  15. The ankle ergometer: A new tool for quantifying changes in mechanical properties of human muscle as a result of spaceflight

    NASA Astrophysics Data System (ADS)

    Mainar, A.; Vanhoutte, C.; Pérot, C.; Voronine, L.; Goubel, F.

    A mechanical device for studying changes in mechanical properties of human muscle as a result of spaceflight is presented. Its main capacities are to allow during a given experiment investigation of both contractile and visco-elastic properties of a musculo-articular complex using respectively isometric contractions, isokinetic movements, quick-release tests and sinusoidal perturbations. This device is a motor driven ergometer associated to an experimental protocol designed for pre- and post-flight experiments. As microgravity preferentially affects postural muscles, the apparatus was designed to test muscle groups crossing the ankle joint. Three subjects were tested during the Euromir '94 mission. Preliminary results obtained on the european astronaut are briefly reported. During the next two years the experiments will be performed during six missions.

  16. YIELD AND GRADE OF VALENCIA PEANUT IN SINGLE ROW, TWIN ROW, AND DIAMOND PLANTING PATTERNS

    USDA-ARS?s Scientific Manuscript database

    A study was conducted at Wayne Baker’s farm South of Clovis in 2006 to compare single row, twin row, and diamond planting patterns in Valencia peanut on 36 inch beds. The twin row and diamond pattern treatments were planted with an experimental planter developed at the USDA-ARS National Peanut Rese...

  17. : Light Interception in Single Row, Twin Row, and Diamond Planting Patterns of Valencia Peanut

    USDA-ARS?s Scientific Manuscript database

    A field study was conducted on a growers farm South of Clovis, NM in 2006 to compare light interception and radiation use efficiency in single row, twin row, and diamond planted Valencia peanuts with line quantum sensors (Apogee instruments, Logan) installed across the crop row. Data were recorded ...

  18. Mechanics of a rope-braked cycle ergometer flywheel and its use for physiological measurement.

    PubMed

    Franklin, Kathryn L; Gordon, Rae S; Baker, Julien S; Davies, Bruce

    2005-01-01

    The cycle ergometer is one of the main tools used by physiologists in studies involving the measurement of work or power against physiological criteria. The current mechanical analysis of a Monark 824E rope-braked ergometer is based on a simplified approach. In this study a detailed analysis of the system is adopted to increase understanding. The mechanics of the ergometer flywheel are explained using data generated experimentally and the detailed components of the values of work that comprise the total work done by a subject are discussed. The total work done by a subject in 2.5 minutes at a speed of 60 rpm against a brake mass of 3 kg was 23,034 J compared with the value of 27,000 J that normally would be attributed using the traditional calculations. This 15% difference is mainly due to the incorrect assumption that the brake load is the force due to the basket mass.

  19. Mary Budd Rowe: A Storyteller of Science

    ERIC Educational Resources Information Center

    Bianchini, Julie A.

    2008-01-01

    This article examines Mary Budd Rowe's groundbreaking and far-reaching contributions to science education. Rowe is best known for her research on wait-time: the idea that teachers can improve the quality and length of classroom discussions by waiting at least 3 s before and after student responses. Her wait-time research grew from and helped…

  20. On Row Rank Equal Column Rank

    ERIC Educational Resources Information Center

    Khalili, Parviz

    2009-01-01

    We will prove a well-known theorem in Linear Algebra, that is, for any "m x n" matrix the dimension of row space and column space are the same. The proof is based on the subject of "elementary matrices" and "reduced row-echelon" form of a matrix.

  1. Rows=Wildlife Corridors: An Urban Resource.

    ERIC Educational Resources Information Center

    Young, Darrell D.

    1983-01-01

    Linear strips of land associated with highways, electrical transmission lines, gas/oil pipelines (called right-of-way or ROWs) are inhibited by a variety of wildlife and offer a unique opportunity to study the wildlife in the urban setting. Types of wildlife found in and importance of ROWs are discussed. (JN)

  2. On Row Rank Equal Column Rank

    ERIC Educational Resources Information Center

    Khalili, Parviz

    2009-01-01

    We will prove a well-known theorem in Linear Algebra, that is, for any "m x n" matrix the dimension of row space and column space are the same. The proof is based on the subject of "elementary matrices" and "reduced row-echelon" form of a matrix.

  3. Comparison of a kayaking ergometer protocol with an arm crank protocol for evaluating peak oxygen consumption.

    PubMed

    Forbes, Scott C; Chilibeck, Philip D

    2007-11-01

    The purpose of this study was to compare a kayak ergometer protocol with an arm crank protocol for determining peak oxygen consumption (V(.-)O2). On separate days in random order, 10 men and 5 women (16-24 years old) with kayaking experience completed the kayak ergometer protocol and a standardized arm crank protocol. The kayak protocol began at 70 strokes per minute and increased by 10 strokes per minute every 2 minutes until volitional fatigue. The arm crank protocol consisted of a crank rate of 70 revolutions per minute, initial loading of 35 W and subsequent increases of 35 W every 2 minutes until volitional fatigue. The results showed a significant difference (p < 0.01) between the kayak ergometer and the arm crank protocols for relative peak V(.-)O2 (47.5 +/- 3.9 ml x kg(-1) x min(-1) vs. 44.2 +/- 6.2 ml x kg(-1) x min(-1)) and absolute peak V(.-)O2 (3.38 L x min(-1) +/- 0.53 vs. 3.14 +/- 0.64 L x min(-1)). The correlation between kayak and arm crank protocol was 0.79 and 0.90, for relative and absolute V(.-)O2 peak, respectively (both p < 0.01). The higher peak V(.-)O2 on the kayak ergometer may be due to the greater muscle mass involved compared to the arm crank ergometer. The kayak ergometer protocol may therefore be more specific to the sport of kayaking than an arm crank protocol.

  4. Biomechanical Performance of Medial Row Suture Placement Relative to the Musculotendinous Junction in Transosseous Equivalent Suture Bridge Double-Row Rotator Cuff Repair.

    PubMed

    Virk, Mandeep S; Bruce, Benjamin; Hussey, Kristen E; Thomas, Jacqueline M; Luthringer, Tyler A; Shewman, Elizabeth F; Wang, Vincent M; Verma, Nikhil N; Romeo, Anthony A; Cole, Brian J

    2017-02-01

    To compare the biomechanical performance of medial row suture placement relative to the musculotendinous junction (MTJ) in a cadaveric transosseous equivalent suture bridge (TOE-SB) double-row (DR) rotator cuff repair (RCR) model. A TOE-SB DR technique was used to reattach experimentally created supraspinatus tendon tears in 9 pairs of human cadaveric shoulders. The medial row sutures were passed either near the MTJ (MTJ group) or 10 mm lateral to the MTJ (rotator cuff tendon [RCT] group). After the supraspinatus repair, the specimens underwent cyclic loading and load to failure tests. The localized displacement of the markers affixed to the tendon surface was measured with an optical tracking system. The MTJ group showed a significantly higher (P = .03) medial row failure (5/9; 3 during cyclic testing and 2 during load to failure testing) compared with the RCT group (0/9). The mean number of cycles completed during cyclic testing was lower in the MTJ group (77) compared with the RCT group (100; P = .07) because 3 specimens failed in the MTJ group during cyclic loading. There were no significant differences between the 2 study groups with respect to biomechanical properties during the load to failure testing. In a cadaveric TOE-SB DR RCR model, medial row sutures through the MTJ results in a significantly higher rate of medial row failure. In rotator cuff tears with tendon tissue loss, passage of medial row sutures through the MTJ should be avoided in a TOE-SB RCR technique because of the risk of medial row failure. Copyright © 2016. Published by Elsevier Inc.

  5. Biomechanical advantages of triple-loaded suture anchors compared with double-row rotator cuff repairs.

    PubMed

    Barber, F Alan; Herbert, Morley A; Schroeder, F Alexander; Aziz-Jacobo, Jorge; Mays, Matthew M; Rapley, Jay H

    2010-03-01

    To evaluate the strength and suture-tendon interface security of various suture anchors triply and doubly loaded with ultrahigh-molecular weight polyethylene-containing sutures and to evaluate the relative effectiveness of placing these anchors in a single-row or double-row arrangement by cyclic loading and then destructive testing. The infraspinatus muscle was reattached to the original humeral footprint by use of 1 of 5 different repair patterns in 40 bovine shoulders. Two single-row repairs and three double-row repairs were tested. High-strength sutures were used for all repairs. Five groups were studied: group 1, 2 triple-loaded screw suture anchors in a single row with simple stitches; group 2, 2 triple-loaded screw anchors in a single row with simple stitches over a fourth suture passed perpendicularly ("rip-stop" stitch); group 3, 2 medial and 2 lateral screw anchors with a single vertical mattress stitch passed from the medial anchors and 2 simple stitches passed from the lateral anchors; group 4, 2 medial double-loaded screw anchors tied in 2 mattress stitches and 2 push-in lateral anchors capturing the medial sutures in a "crisscross" spanning stitch; and group 5, 2 medial double-loaded screw anchors tied in 2 mattress stitches and 2 push-in lateral anchors creating a "suture-bridge" stitch. The specimens were cycled between 10 and 180 N at 1.0 Hz for 3,500 cycles or until failure. Endpoints were cyclic loading displacement (5 and 10 mm), total displacement, and ultimate failure load. A single row of triply loaded anchors was more resistant to stretching to a 5- and 10-mm gap than the double-row repairs with or without the addition of a rip-stop suture (P < .05). The addition of a rip-stop stitch made the repair more resistant to gap formation than a double row repair (P < .05). The crisscross double row created by 2 medial double-loaded suture anchors and 2 lateral push-in anchors stretched more than any other group (P < .05). Double-row repairs with

  6. Foot orthoses do not affect crank power output during maximal exercise on a cycle-ergometer.

    PubMed

    Yeo, Boon K; Rouffet, David M; Bonanno, Daniel R

    2016-05-01

    To investigate the effects of custom-made foot orthoses on the torque- and power-cadence relationships and perceived comfort during maximal cycling exercises in a population of competitive road cyclists. Randomised, repeated measures, participant-blinded controlled study. Twenty-four competitive road cyclists (22 males, 2 females; aged 18-53 years) with mobile feet performed the torque-velocity test with custom-made and sham foot orthoses. For both conditions, the maximal power, optimal cadence, optimal torque, maximal torque, and maximal cadence were extracted from the individual torque- and power-cadence relationships. Comfort was assessed on a 150mm visual analogue scale. Paired-samples t-tests were used for comparison of means between conditions. No differences were observed between the custom-made and sham foot orthoses for any of the key variables extracted: maximal power (1022±180 vs. 1020±172W; p=0.794), optimal cadence (118±10 vs. 119±9rpm; p=0.682), optimal torque (82±10 vs. 82±11Nm; p=0.559), maximal torque (157±23 vs. 159±20 Nm; p=0.665) and maximal cadence (220±22 vs. 221±20rpm; p=0.935). There was no difference in comfort between custom-made and sham foot orthoses (106±30.5 vs. 116±25.0mm; p=0.995). Compared to the sham foot orthoses, the custom-made foot orthoses did not significantly affect the torque and power generating capacities or comfort during a maximal exercise performed on a stationary cycle ergometer. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  7. Heart rate regulation during cycle-ergometer exercise via event-driven biofeedback.

    PubMed

    Argha, Ahmadreza; Su, Steven W; Celler, Branko G

    2017-03-01

    This paper is devoted to the problem of regulating the heart rate response along a predetermined reference profile, for cycle-ergometer exercises designed for training or cardio-respiratory rehabilitation. The controller designed in this study is a non-conventional, non-model-based, proportional, integral and derivative (PID) controller. The PID controller commands can be transmitted as biofeedback auditory commands, which can be heard and interpreted by the exercising subject to increase or reduce exercise intensity. However, in such a case, for the purposes of effectively communicating to the exercising subject a change in the required exercise intensity, the timing of this feedback signal relative to the position of the pedals becomes critical. A feedback signal delivered when the pedals are not in a suitable position to efficiently exert force may be ineffective and this may, in turn, lead to the cognitive disengagement of the user from the feedback controller. This note examines a novel form of control system which has been expressly designed for this project. The system is called an "actuator-based event-driven control system". The proposed control system was experimentally verified using 24 healthy male subjects who were randomly divided into two separate groups, along with cross-validation scheme. A statistical analysis was employed to test the generalisation of the PID tunes, derived based on the average transfer functions of the two groups, and it revealed that there were no significant differences between the mean values of root mean square of the tracking error of two groups (3.9 vs. 3.7 bpm, [Formula: see text]). Furthermore, the results of a second statistical hypothesis test showed that the proposed PID controller with novel synchronised biofeedback mechanism has better performance compared to a conventional PID controller with a fixed-rate biofeedback mechanism (Group 1: 3.9 vs. 5.0 bpm, Group 2: 3.7 vs. 4.4 bpm, [Formula: see text]).

  8. Galaxies with "rows": A new catalog

    NASA Astrophysics Data System (ADS)

    Butenko, M. A.; Khoperskov, A. V.

    2017-07-01

    Galaxies with "rows" in Vorontsov-Velyaminov's terminology stand out among the variety of spiral galactic patterns. A characteristic feature of such objects is the sequence of straight-line segments that forms the spiral arm. In 2001 A. Chernin and co-authors published a catalog of such galaxies which includes 204 objects from the Palomar Atlas. In this paper, we supplement the catalog with 276 objects based on an analysis of all the galaxies from the New General Catalogue and Index Catalogue. The total number of NGC and IC galaxies with rows is 406, including the objects of Chernin et al. (2001). The use of more recent galaxy images allowed us to detect more "rows" on average, compared with the catalog of Chernin et al. When comparing the principal galaxy properties we found no significant differences between galaxies with rows and all S-typeNGC/IC galaxies.We discuss twomechanisms for the formation of polygonal structures based on numerical gas-dynamic and collisionless N-body calculations, which demonstrate that a spiral pattern with rows is a transient stage in the evolution of galaxies and a system with a powerful spiral structure can pass through this stage. The hypothesis of A. Chernin et al. (2001) that the occurrence frequency of interacting galaxies is twice higher among galaxies with rows is not confirmed for the combined set of 480 galaxies. The presence of a central stellar bar appears to be a favorable factor for the formation of a system of "rows".

  9. Mary Budd Rowe: a storyteller of science

    NASA Astrophysics Data System (ADS)

    Bianchini, Julie A.

    2008-12-01

    This article examines Mary Budd Rowe's groundbreaking and far-reaching contributions to science education. Rowe is best known for her research on wait-time: the idea that teachers can improve the quality and length of classroom discussions by waiting at least 3 s before and after student responses. Her wait-time research grew from and helped inform her staunch advocacy of science education as inquiry; Rowe saw wonder and excitement as central to the teaching and learning of science. She spent much of her professional life designing professional development experiences and innovative curriculum materials to help teachers, particularly elementary school teachers, enact inquiry in their classrooms.

  10. Memory hierarchy using row-based compression

    DOEpatents

    Loh, Gabriel H.; O'Connor, James M.

    2016-10-25

    A system includes a first memory and a device coupleable to the first memory. The device includes a second memory to cache data from the first memory. The second memory includes a plurality of rows, each row including a corresponding set of compressed data blocks of non-uniform sizes and a corresponding set of tag blocks. Each tag block represents a corresponding compressed data block of the row. The device further includes decompression logic to decompress data blocks accessed from the second memory. The device further includes compression logic to compress data blocks to be stored in the second memory.

  11. Health benefits of cycle ergometer training for older adults over 70: a review.

    PubMed

    Bouaziz, Walid; Schmitt, Elise; Kaltenbach, Georges; Geny, Bernard; Vogel, Thomas

    2015-01-01

    As the number of older adults continues to increase worldwide, more attention is being paid to geriatric health care needs, and successful ageing is becoming an important topic in the medical literature. A preventive approach to the care of older adults is thus a priority in our aging societies. The purpose of this study was to update evidence for the health benefits of cycle ergometer training for older adults over 70. We searched online electronic databases up to September 2014 for original observational and intervention studies on the relationship between cycle ergometer training and health among older patients over 70. Twenty-five studies examined interventions aimed specifically at promoting cycling for older adults over 70. These studies reported a positive effect on the prevention of cardiovascular disease, and a significant improvement in metabolic responses. Improving functional status, muscle strength and cognitive performance are also well established. Overall, this review demonstrates a positive effect of cycle ergometer training with functional benefits and positive health outcomes for older adults over 70. Based on this evidence, clinicians can now encourage older adults to profit from the health benefits of cycle ergometer training to be able to pursue their daily activities independently.

  12. Astronaut Paul Weitz prepares to use bicycle ergometer in Skylab trainer

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Paul J. Weitz, pilot for the first manned Skylab mission, prepares to check out the bicycle ergometer in the work and experiments area of the crew quarters of the Skylab Orbital Workshop (OWS) trainer during Skylab training at the Johnson Space Center. Scientist-Astronaut Joseph P. Kerwin, science pilot of the mission, is in the background.

  13. Magnus on Cycle Ergometer with Vibration Isolation System (CEVIS) in US Laboratory Destiny

    NASA Image and Video Library

    2009-03-22

    ISS018-E-042649 (22 March 2009) --- Astronaut Sandra Magnus, STS-119 mission specialist, exercises on the Cycle Ergometer with Vibration Isolation System (CEVIS) in the Destiny laboratory of the International Space Station while Space Shuttle Discovery remains docked with the station.

  14. Commander Rominger on a cycle ergometer on the middeck of Endeavour during STS-100

    NASA Image and Video Library

    2001-04-23

    S100-E-5342 (23 April 2001) --- Astronaut Kent V. Rominger, STS-100 mission commander, economizes his time as he looks over flight data while working out on an ergometer device on the middeck of the Space Shuttle Endeavour. The scene was recorded with a digital still camera.

  15. Astronaut Paul Weitz prepares to use bicycle ergometer in Skylab trainer

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Paul J. Weitz, pilot for the first manned Skylab mission, prepares to check out the bicycle ergometer in the work and experiments area of the crew quarters of the Skylab Orbital Workshop (OWS) trainer during Skylab training at the Johnson Space Center. Scientist-Astronaut Joseph P. Kerwin, science pilot of the mission, is in the background.

  16. Modeling of breath methane concentration profiles during exercise on an ergometer*

    PubMed Central

    Szabó, Anna; Unterkofler, Karl; Mochalski, Pawel; Jandacka, Martin; Ruzsanyi, Vera; Szabó, Gábor; Mohácsi, Árpád; Teschl, Susanne; Teschl, Gerald; King, Julian

    2016-01-01

    We develop a simple three compartment model based on mass balance equations which quantitatively describes the dynamics of breath methane concentration profiles during exercise on an ergometer. With the help of this model it is possible to estimate the endogenous production rate of methane in the large intestine by measuring breath gas concentrations of methane. PMID:26828421

  17. Triple-Loaded Single-Row Versus Suture-Bridge Double-Row Rotator Cuff Tendon Repair With Platelet-Rich Plasma Fibrin Membrane: A Randomized Controlled Trial.

    PubMed

    Barber, F Alan

    2016-05-01

    To compare the structural healing and clinical outcomes of triple-loaded single-row with suture-bridging double-row repairs of full-thickness rotator cuff tendons when both repair constructs are augmented with platelet-rich plasma fibrin membrane. A prospective, randomized, consecutive series of patients diagnosed with full-thickness rotator cuff tears no greater than 3 cm in anteroposterior length were treated with a triple-loaded single-row (20) or suture-bridging double-row (20) repair augmented with platelet-rich plasma fibrin membrane. The primary outcome measure was cuff integrity by magnetic resonance imaging (MRI) at 12 months postoperatively. Secondary clinical outcome measures were American Shoulder and Elbow Surgeons, Rowe, Simple Shoulder Test, Constant, and Single Assessment Numeric Evaluation scores. The mean MRI interval was 12.6 months (range, 12-17 months). A total of 3 of 20 single-row repairs and 3 of 20 double-row repairs (15%) had tears at follow-up MRI. The single-row group had re-tears in 1 single tendon repair and 2 double tendon repairs. All 3 tears failed at the original attachment site (Cho type 1). In the double-row group, re-tears were found in 3 double tendon repairs. All 3 tears failed medial to the medial row near the musculotendinous junction (Cho type 2). All clinical outcome measures were significantly improved from the preoperative level (P < .0001), but there was no statistical difference between groups postoperatively. There is no MRI difference in rotator cuff tendon re-tear rate at 12 months postsurgery between a triple-loaded single-row repair or a suture-bridging double-row repair when both are augmented with platelet-rich plasma fibrin membrane. No difference could be demonstrated between these repairs on clinical outcome scores. I, Prospective randomized study. Copyright © 2016 Arthroscopy Association of North America. All rights reserved.

  18. Effect of row-to-row shading on the output of flat-plate south-facing photovoltaic arrays

    SciTech Connect

    Goswami, D.Y.; Hassan, A.Y.; Collis, J. ); Stefanakos, E.K. )

    1989-08-01

    When solar arrays (photovoltaic, thermal, etc.) are arranged in multiple rows of modules, all but the first row suffer reduction in (power) output, even when sufficient spacing between rows is provided. The reduction in output power occurs because the first row prevents some of the diffuse and reflected radiation from reaching the row directly behind it. This work presents estimates of the effect of shading on the amounts of solar radiation received by consecutive rows of flat-plate arrays.

  19. Functional Outcomes after Double Row Versus Single Row Rotator Cuff Repair

    PubMed Central

    Nicholas, Stephen J.; Lee, Steven J.; Mullaney, Michael John; Tyler, Timothy F.; Johnson, Christopher D.; Fukunaga, Takumi; McHugh, Malachy P.

    2015-01-01

    Objectives: The effect of single row (SR) versus double row (DR) rotator cuff repair on functional outcomes was examined in a prospective randomized design. Methods: Fifty patients were randomized to DR or SR repairs; 39 patients (13 women, 26 men, 23 SR, 16 DR, age 62±7 yr) were assessed at an average of 2.2±1.6 yr after surgery (range 1-7 yr; tear size 17 medium, 13 large, 9 massive). The following data were recorded prior to surgery and at follow-up: Penn, ASES and Simple Shoulder Test (SST) scores; range of motion (ROM) for shoulder flexion, external rotation (ER) at 0º and 90º abduction, and internal rotation (IR) at 90º abduction; shoulder strength (Lafayette Manual Muscle Tester) in empty and full can tests, abduction and ER at 0º abduction. Treatment (SR vs. DR) by Time (pre-op vs. post-op) mixed model analysis of variance was used to assess the effect of rotator cuff repair. It was estimated that with 20 patients per group a 10-point difference in improvement in ASES scores between SR and DR treatments could be detected at an alpha level of 0.05 with 80% power. Results: Outcome Scores: RC repair markedly improved Penn, ASES and SST scores (P<0.001), with similar improvement between single versus double row repairs (Treatment by Time P=.49 to P=.67), and excellent scores at follow-up (Double Row vs. Single Row: Penn 91±11 vs. 91±12, P=.98; ASES 92±9 vs 87 ±15, P=.24; SST 11.2±1.2 vs. 11.4±1.0, P=.58). ROM: Patients with DR repairs lost ER ROM at 0º abduction (pre-op to final follow-up 7±10º loss, P=.013). ER ROM did not change with SR repair (3.9±15.6º gain, P=.24; Treatment by Time P=.017). This effect was not apparent for ER ROM at 90º abduction (Treatment by Time P=.26). IR ROM improved from pre-op to final follow-up (P<0.01, SR 17±18º, DR 13±23º, Treatment by Time P=.31). Strength: RC repair markedly improved strength in Empty Can (51%), Full Can (54%), Abduction (45%) and ER (31 %) strength (all P<.001), with no difference between

  20. Effect of Kayak Ergometer Elastic Tension on Upper Limb EMG Activity and 3D Kinematics.

    PubMed

    Fleming, Neil; Donne, Bernard; Fletcher, David

    2012-01-01

    Despite the prevalence of shoulder injury in kayakers, limited published research examining associated upper limb kinematics and recruitment patterns exists. Altered muscle recruitment patterns on-ergometer vs. on-water kayaking were recently reported, however, mechanisms underlying changes remain to be elucidated. The current study assessed the effect of ergometer recoil tension on upper limb recruitment and kinematics during the kayak stroke. Male kayakers (n = 10) performed 4 by 1 min on-ergometer exercise bouts at 85%VO2max at varying elastic recoil tension; EMG, stroke force and three-dimensional 3D kinematic data were recorded. While stationary recoil forces significantly increased across investigated tensions (125% increase, p < 0.001), no significant differences were detected in assessed force variables during the stroke cycle. In contrast, increasing tension induced significantly higher Anterior Deltoid (AD) activity in the latter stages (70 to 90%) of the cycle (p < 0.05). No significant differences were observed across tension levels for Triceps Brachii or Latissimus Dorsi. Kinematic analysis revealed that overhead arm movements accounted for 39 ± 16% of the cycle. Elbow angle at stroke cycle onset was 144 ± 10°; maximal elbow angle (151 ± 7°) occurred at 78 ± 10% into the cycle. All kinematic markers moved to a more anterior position as tension increased. No significant change in wrist marker elevation was observed, while elbow and shoulder marker elevations significantly increased across tension levels (p < 0.05). In conclusion, data suggested that kayakers maintained normal upper limb kinematics via additional AD recruitment despite ergometer induced recoil forces. Key pointsKayak ergometer elastic tension significantly alters Anterior Deltoid recruitment patterns.Kayakers maintain optimal arm kinematics despite changing external forces via altered shoulder muscle recruitment.Overhead arm movements account for a high proportion of the kayak

  1. Effect of Kayak Ergometer Elastic Tension on Upper Limb EMG Activity and 3D Kinematics

    PubMed Central

    Fleming, Neil; Donne, Bernard; Fletcher, David

    2012-01-01

    Despite the prevalence of shoulder injury in kayakers, limited published research examining associated upper limb kinematics and recruitment patterns exists. Altered muscle recruitment patterns on-ergometer vs. on-water kayaking were recently reported, however, mechanisms underlying changes remain to be elucidated. The current study assessed the effect of ergometer recoil tension on upper limb recruitment and kinematics during the kayak stroke. Male kayakers (n = 10) performed 4 by 1 min on-ergometer exercise bouts at 85%VO2max at varying elastic recoil tension; EMG, stroke force and three-dimensional 3D kinematic data were recorded. While stationary recoil forces significantly increased across investigated tensions (125% increase, p < 0.001), no significant differences were detected in assessed force variables during the stroke cycle. In contrast, increasing tension induced significantly higher Anterior Deltoid (AD) activity in the latter stages (70 to 90%) of the cycle (p < 0.05). No significant differences were observed across tension levels for Triceps Brachii or Latissimus Dorsi. Kinematic analysis revealed that overhead arm movements accounted for 39 ± 16% of the cycle. Elbow angle at stroke cycle onset was 144 ± 10°; maximal elbow angle (151 ± 7°) occurred at 78 ± 10% into the cycle. All kinematic markers moved to a more anterior position as tension increased. No significant change in wrist marker elevation was observed, while elbow and shoulder marker elevations significantly increased across tension levels (p < 0.05). In conclusion, data suggested that kayakers maintained normal upper limb kinematics via additional AD recruitment despite ergometer induced recoil forces. Key pointsKayak ergometer elastic tension significantly alters Anterior Deltoid recruitment patterns.Kayakers maintain optimal arm kinematics despite changing external forces via altered shoulder muscle recruitment.Overhead arm movements account for a high proportion of the kayak

  2. Oxidative stress and immune system analysis after cycle ergometer use in critical patients

    PubMed Central

    de França, Eduardo Eriko Tenório; Ribeiro, Luana Carneiro; Lamenha, Gabriela Gomes; Magalhães, Isabela Kalline Fidelix; de Gomes Figueiredo, Thainá; Costa, Marthley José Correia; Júnior, Ubiracé Fernando Elihimas; Feitosa, Bárbara Luana; do Amparo Andrade, Maria; Júnior, Marco Aurélio Valois Correia; Ramos, Francimar Ferrari; de Castro, Célia Maria Machado Barbosa

    2017-01-01

    OBJECTIVE: The passive cycle ergometer aims to prevent hypotrophy and improve muscle strength, with a consequent reduction in hospitalization time in the intensive care unit and functional improvement. However, its effects on oxidative stress and immune system parameters remain unknown. The aim of this study is to analyze the effects of a passive cycle ergometer on the immune system and oxidative stress in critical patients. METHODS: This paper describes a randomized controlled trial in a sample of 19 patients of both genders who were on mechanical ventilation and hospitalized in the intensive care unit of the Hospital Agamenom Magalhães. The patients were divided into two groups: one group underwent cycle ergometer passive exercise for 30 cycles/min on the lower limbs for 20 minutes; the other group did not undergo any therapeutic intervention during the study and served as the control group. A total of 20 ml of blood was analysed, in which nitric oxide levels and some specific inflammatory cytokines (tumour necrosis factor alpha (TNF-α), interferon gamma (IFN-γ) and interleukins 6 (IL-6) and 10 (IL-10)) were evaluated before and after the study protocol. RESULTS: Regarding the demographic and clinical variables, the groups were homogeneous in the early phases of the study. The nitric oxide analysis revealed a reduction in nitric oxide variation in stimulated cells (p=0.0021) and those stimulated (p=0.0076) after passive cycle ergometer use compared to the control group. No differences in the evaluated inflammatory cytokines were observed between the two groups. CONCLUSION: We can conclude that the passive cycle ergometer promoted reduced levels of nitric oxide, showing beneficial effects on oxidative stress reduction. As assessed by inflammatory cytokines, the treatment was not associated with changes in the immune system. However, further research in a larger population is necessary for more conclusive results. PMID:28355359

  3. Fatigue and physical function after hysterectomy measured by SF-36, ergometer, and dynamometer.

    PubMed

    Lauszus, Finn F; Kallfa, Ervin; Madsen, Mogens R

    2016-07-01

    Information is limited on the early postoperative rehabilitation following hysterectomy. Our purpose was to evaluate the different perioperative modalities of fatigue, pain, quality of life, and physical performance and their time-related. A prospective, follow-up study of a cohort of women undergoing abdominal and vaginal hysterectomy at the Gynecology Department at Herning Hospital, Denmark. Data from 108 women with elective hysterectomy were compared pre- and postoperatively. The fatigue level was scored on a visual analogue scale and SF-36. Objective measurements were performed by dynamometer of hand grip, knee extension strength, and postural stability; further, by ergometer cycle work capacity and by impedance lean body mass. Quality of life was assessed using the SF-36 questionnaire. Patients were examined preoperatively and twice postoperatively. Women lost lean body mass 13 and 30 days after their hysterectomy (p < 0.01). Strength in hand (p < 0.05) and knees (p < 0.01) increased compared to preoperative values but no change in postural stability and work capacity was noted. Fatigue resumed to preoperative levels after 30 days. SF-36 revealed that the modality of 'physical functioning' and 'role limitations due to physical problems' remained significantly decreased at the end of the study (p < 0.01) CONCLUSION: Hysterectomy was associated with reduction in physical function assessed by SF-36 30 days after surgery. No impairment of performance was found in physical tests at days 13 and 30 postoperatively.

  4. Determinants of oxygen consumption during exercise on cycle ergometer: the effects of gravity acceleration.

    PubMed

    Bonjour, Julien; Capelli, Carlo; Antonutto, Guglielmo; Calza, Stefano; Tam, Enrico; Linnarsson, Dag; Ferretti, Guido

    2010-04-30

    The hypothesis that changes in gravity acceleration (a(g)) affect the linear relationships between oxygen consumption VO2 and mechanical power (w ) so that at any w, VO2 increases linearly with a(g) was tested under conditions where the weight of constant-mass legs was let to vary by inducing changes in a(g) in a human centrifuge. The effects of a(g) on the VO2/w relationship were studied on 14 subjects at two pedalling frequencies (f(p), 1.0 and 1.5 Hz), during four work loads on a cycle ergometer (25, 50, 75 and 100 W) and at four a(g) levels (1.0, 1.5, 2.0 and 2.5 times normal gravity). VO2 increased linearly with w. The slope did not differ significantly at various a(g) and f(p), suggesting invariant mechanical efficiency during cycling, independent of f(p) and a(g). Conversely, the y-intercept of the VO2/w relationship, defined as constant b, increased linearly with a(g). Constant b is the sum of resting VO2 plus internal metabolic power (E (i)). Since the former was the same at all investigated a(g), the increase in constant b was entirely due to an increase in E (i). Since the VO2 versus w lines had similar slopes, the changes in E (i) entirely explained the higher VO2 at each w, as a(g) was increased. In conclusion, the effects of a(g) on VO2 are mediated through changes in E (i), and not in w or in resting VO2. (c) 2010. Published by Elsevier B.V.

  5. Multichannel Double-Row Transmission Line Array for Human MR Imaging at Ultrahigh Fields.

    PubMed

    Yan, Xinqiang; Pedersen, Jan Ole; Wei, Long; Zhang, Xiaoliang; Xue, Rong

    2015-06-01

    In microstrip transmission line (MTL) transmit/receive (transceive) arrays used for ultrahigh field MRI, the array length is often constrained by the required resonant frequency, limiting the image coverage. The purpose of this study is to increase the imaging coverage and also improve its parallel imaging capability by utilizing a double-row design. A 16-channel double-row MTL transceive array was designed, constructed, and tested for human head imaging at 7 T. Array elements between two rows were decoupled by using the induced current elimination or magnetic wall decoupling technique. In vivo human head images were acquired, and g-factor results were calculated to evaluate the performance of this double-row array. Testing results showed that all coil elements were well decoupled with a better than -18 dB transmission coefficient between any two elements. The double-row array improves the imaging quality of the lower portion of the human head, and has low g-factors even at high acceleration rates. Compared with a regular single-row MTL array, the double-row array demonstrated a larger imaging coverage along the z-direction with improved parallel imaging capability. The proposed technique is particularly suitable for the design of large-sized transceive arrays with large channel counts, which ultimately benefits the imaging performance in human MRI.

  6. Multichannel Double-Row Transmission Line Array for Human MR Imaging at Ultrahigh Fields

    PubMed Central

    Yan, Xinqiang; Pedersen, Jan Ole; Wei, Long

    2017-01-01

    Objective In microstrip transmission line (MTL) transmit/receive (transceive) arrays used for ultrahigh field MRI, the array length is often constrained by the required resonant frequency, limiting the image coverage. The purpose of this study is to increase the imaging coverage and also improve its parallel imaging capability by utilizing a double-row design. Methods A 16-channel double-row MTL transceive array was designed, constructed, and tested for human head imaging at 7 T. Array elements between two rows were decoupled by using the induced current elimination or magnetic wall decoupling technique. In vivo human head images were acquired, and g-factor results were calculated to evaluate the performance of this double-row array. Results Testing results showed that all coil elements were well decoupled with a better than −18 dB transmission coefficient between any two elements. The double-row array improves the imaging quality of the lower portion of the human head, and has low g-factors even at high acceleration rates. Conclusion Compared with a regular single-row MTL array, the double-row array demonstrated a larger imaging coverage along the z-direction with improved parallel imaging capability. Significance The proposed technique is particularly suitable for the design of large-sized transceive arrays with large channel counts, which ultimately benefits the imaging performance in human MRI. PMID:25706499

  7. Cerebrovascular responses during rowing: Do circadian rhythms explain morning and afternoon performance differences?

    PubMed

    Faull, O K; Cotter, J D; Lucas, S J E

    2015-08-01

    The purpose of this study was to characterize cerebrovascular responses to rowing exercise, investigating whether their diurnal variation might explain performance differences across a day. Twelve male rowers completed incremental rowing exercise and a 2000-m ergometer time trial at 07:00 h and 16:00 h, 1 week apart, while middle cerebral artery velocity (MCAv), cerebral (prefrontal), and muscular (vastus lateralis) tissue oxygenation and hemoglobin volume (via near-infrared spectroscopy), heart rate, and pressure of end-tidal CO2 (PET CO2) were recorded. MCAv was 20-25% above resting levels (68 ± 12 cm/s) during submaximal and maximal exercise intensities, despite PET CO2 being reduced during maximal efforts (down ∼ 0.5-0.8 kPa); thus revealing a different perfusion profile to the inverted-U observed in other exercise modes. The afternoon time trial was 3.4 s faster (95% confidence interval 0.9-5.8 s) and mean power output 3.2% higher (337 vs 347 W; P = 0.04), in conjunction with similar exercise-induced elevations in MCAv (P = 0.60) and reductions in cerebral oxygenation (TOI) (P = 0.12). At the muscle, afternoon trials involved similar oxygen extraction (HHb volume and TOI) albeit from a relatively lower total Hb volume (P < 0.01). In conclusion, rowing performance was better in the afternoon, but not in conjunction with differences in MCAv or exercise-induced differences in cerebral oxygenation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Closely-spaced double-row microstrip RF arrays for parallel MR imaging at ultrahigh fields.

    PubMed

    Yan, Xinqiang; Xue, Rong; Zhang, Xiaoliang

    2015-11-01

    Radiofrequency (RF) coil arrays with high count of elements, e.g., closely-spaced multi-row arrays, exhibit superior parallel imaging performance in MRI. However, it is technically challenging and time-consuming to build multi-row arrays due to complex coupling issues. This paper presents a novel and simple method for closely-spaced multi-row RF array designs. Induced current elimination (ICE) decoupling method has shown the capability of reducing coupling between microstrip elements from different rows. In this study, its capability for decoupling array elements from the same row was investigated and validated by bench tests, with an isolation improvement from -8.9 dB to -20.7 dB. Based on this feature, a closely-spaced double-row microstrip array with 16 elements was built at 7T. S21 between any two elements of the 16-channel closely-spaced was better than -14 dB. In addition, its feasibility and performance was validated by MRI experiments. No significant image reconstruction- related noise amplifications were observed for parallel imaging even when reduced factor (R) achieves 4. The experimental results demonstrated that the proposed design might be a simple and efficient approach in fabricating closely-spaced multi-row RF arrays.

  9. Closely-spaced double-row microstrip RF arrays for parallel MR imaging at ultrahigh fields

    PubMed Central

    Yan, Xinqiang; Xue, Rong; Zhang, Xiaoliang

    2015-01-01

    Radiofrequency (RF) coil arrays with high count of elements, e.g., closely-spaced multi-row arrays, exhibit superior parallel imaging performance in MRI. However, it is technically challenging and time-consuming to build multi-row arrays due to complex coupling issues. This paper presents a novel and simple method for closely-spaced multi-row RF array designs. Induced current elimination (ICE) decoupling method has shown the capability of reducing coupling between microstrip elements from different rows. In this study, its capability for decoupling array elements from the same row was investigated and validated by bench tests, with an isolation improvement from −8.9 dB to −20.7 dB. Based on this feature, a closely-spaced double-row microstrip array with 16 elements was built at 7T. S21 between any two elements of the 16-channel closely-spaced was better than −14 dB. In addition, its feasibility and performance was validated by MRI experiments. No significant image reconstruction- related noise amplifications were observed for parallel imaging even when reduced factor (R) achieves 4. The experimental results demonstrated that the proposed design might be a simple and efficient approach in fabricating closely-spaced multi-row RF arrays. PMID:26508810

  10. Developing Formulas by Skipping Rows in Pascal's Triangle

    ERIC Educational Resources Information Center

    Buonpastore, Robert J.; Osler, Thomas J.

    2007-01-01

    A table showing the first thirteen rows of Pascal's triangle, where the rows are, as usual numbered from 0 to 12 is presented. The entries in the table are called binomial coefficients. In this note, the authors systematically delete rows from Pascal's triangle and, by trial and error, try to find a formula that allows them to add new rows to the…

  11. Developing Formulas by Skipping Rows in Pascal's Triangle

    ERIC Educational Resources Information Center

    Buonpastore, Robert J.; Osler, Thomas J.

    2007-01-01

    A table showing the first thirteen rows of Pascal's triangle, where the rows are, as usual numbered from 0 to 12 is presented. The entries in the table are called binomial coefficients. In this note, the authors systematically delete rows from Pascal's triangle and, by trial and error, try to find a formula that allows them to add new rows to the…

  12. CT Coronary Angiography: 256-Slice and 320-Detector Row Scanners

    PubMed Central

    Hsiao, Edward M.; Rybicki, Frank J.; Steigner, Michael

    2010-01-01

    Multidetector computed tomography (MDCT) has rapidly evolved from 4-detector row systems in 1998 to 256-slice and 320-detector row CT systems. With smaller detector element size and faster gantry rotation speed, spatial and temporal resolution of the 64-detector MDCT scanners have made coronary artery imaging a reliable clinical test. Wide-area coverage MDCT, such as the 256-slice and 320-detector row MDCT scanners, has enabled volumetric imaging of the entire heart free of stair-step artifacts at a single time point within one cardiac cycle. It is hoped that these improvements will be realized with greater diagnostic accuracy of CT coronary angiography. Such scanners hold promise in performing a rapid high quality “triple rule-out” test without high contrast load, improved myocardial perfusion imaging, and even four-dimensional CT subtraction angiography. These emerging technical advances and novel applications will continue to change the way we study coronary artery disease beyond detecting luminal stenosis. PMID:20425186

  13. Comparison of Single Row, Twin Row, and Diamond Planting Patterns in Valencia Peanut

    USDA-ARS?s Scientific Manuscript database

    Most Valencia peanuts are grown in single rows on 36 to 40 inch beds. Because of their bunch-type and erect growth habit, Valencia peanuts do not spread over the whole bed and have the opportunity to benefit from multiple row planting arrangements. This study was conducted at locations near Portal...

  14. Comparisons of single-row and twin-row soybean production in the Mid South

    USDA-ARS?s Scientific Manuscript database

    A Maturity Group (MG) IV and MG V soybean [Glycine max (L.) Merr] cultivar were planted in single-rows and twin-rows on 102 cm beds at 20, 30, 40, and 50 seeds m-2 in a Beulah fine sandy loam (coarse-loamy, mixed thermic Typic Dystrochrepts) in 2008, 2009, 2010 and Sharkey clay (Vertic Haplaquept) i...

  15. STS-40 Mission Specialist (MS) Seddon on ergometer conducts Exp. No. 066

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Astride the bicycle ergometer, STS-40 Mission Specialist (MS) M. Rhea Seddon breathes into the cardiovascular rebreathing unit (CRU) during the exercise phase of Experiment No. 066, Inflight Study of Cardiovascular Deconditioning. It focuses on the deconditioning of the heart and lungs and changes in cardiopulmonary function that occur upon return to Earth. By using noninvasive techniques of prolonged expiration and rebreathing, investigators can determine the amount of blood pumped out of the heart (cardiac output), the ease with which blood flows through all the vessels (total peripheral resistance), oxygen used and carbon dioxide released by the body, and lung function and volume changes. Measurements are made both while crewmembers are resting and while they pedal the ergometer. Shirtless, MS James P. Bagian conducts a second experiment in the background.

  16. STS-46 Pilot Allen uses cycle ergometer on OV-104's middeck

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-46 Pilot Andrew M. Allen exercises using the cycle ergometer on the middeck of Atlantis, Orbiter Vehicle (OV) 104. Allen, shirtless, is equipped with sensors for monitoring his biological systems during the exercise session. A communications kit assembly cable freefloats from his headset at his right and in front of the forward lockers. The open airlock hatch appears at his left and the sleep station behind him.

  17. STS-46 Pilot Allen uses cycle ergometer on OV-104's middeck

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-46 Pilot Andrew M. Allen exercises using the cycle ergometer on the middeck of Atlantis, Orbiter Vehicle (OV) 104. Allen, shirtless, is equipped with sensors for monitoring his biological systems during the exercise session. A communications kit assembly cable freefloats from his headset at his right and in front of the forward lockers. The open airlock hatch appears at his left and the sleep station behind him.

  18. [An automatic torque control system for a bicycle ergometer equipped with an eddy current brake].

    PubMed

    Kikinev, V V

    2007-01-01

    The main elements of the loading device of a bicycle ergometer, including an eddy current brake and a torque sensor, are described. The automatic torque control system, which includes the loading device, is equipped with a stabilizing feedback controller that optimally approximates the closed-loop transfer function of the target model. The reduced transfer function model of the controller is of the fourth order. A method featuring a modulation-demodulation loop is suggested for implementation of the control system.

  19. STS-46 Pilot Allen uses cycle ergometer on OV-104's middeck

    NASA Image and Video Library

    1992-08-08

    STS046-24-025 (31 July-8 Aug. 1992) --- Astronaut Andrew M. Allen, STS-46 pilot, exercises on the bicycle ergometer device on the flight deck of the Space Shuttle Atlantis as it makes one of its 127 total orbits for the eight-day mission. Allen, equipped with sensors for monitoring his biological systems during the run, was joined by four other NASA astronauts and two European scientists on the mission.

  20. Altered lower leg muscle activation patterns in patients with cerebral palsy during cycling on an ergometer

    PubMed Central

    Alves-Pinto, Ana; Blumenstein, Tobias; Turova, Varvara; Lampe, Renée

    2016-01-01

    Objective Cycling on a recumbent ergometer constitutes one of the most popular rehabilitation exercises in cerebral palsy (CP). However, no control is performed on how muscles are being used during training. Given that patients with CP present altered muscular activity patterns during cycling or walking, it is possible that an incorrect pattern of muscle activation is being promoted during rehabilitation cycling. This study investigated patterns of muscular activation during cycling on a recumbent ergometer in patients with CP and whether those patterns are determined by the degree of spasticity and of mobility. Methods Electromyographic (EMG) recordings of lower leg muscle activation during cycling on a recumbent ergometer were performed in 14 adult patients diagnosed with CP and five adult healthy participants. EMG recordings were done with an eight-channel EMG system built in the laboratory. The activity of the following muscles was recorded: Musculus rectus femoris, Musculus biceps femoris, Musculus tibialis anterior, and Musculus gastrocnemius. The degree of muscle spasticity and mobility was assessed using the Modified Ashworth Scale and the Gross Motor Function Classification System, respectively. Muscle activation patterns were described in terms of onset and duration of activation as well as duration of cocontractions. Results Muscle activation in CP was characterized by earlier onsets, longer periods of activation, a higher occurrence of agonist–antagonist cocontractions, and a more variable cycling tempo in comparison to healthy participants. The degree of altered muscle activation pattern correlated significantly with the degree of spasticity. Conclusion This study confirmed the occurrence of altered lower leg muscle activation patterns in patients with CP during cycling on a recumbent ergometer. There is a need to develop feedback systems that can inform patients and therapists of an incorrect muscle activation during cycling and support the training

  1. Optical RAM row access using WDM-enabled all-passive row/column decoders

    NASA Astrophysics Data System (ADS)

    Papaioannou, Sotirios; Alexoudi, Theoni; Kanellos, George T.; Miliou, Amalia; Pleros, Nikos

    2014-03-01

    Towards achieving a functional RAM organization that reaps the advantages offered by optical technology, a complete set of optical peripheral modules, namely the Row (RD) and Column Decoder (CD) units, is required. In this perspective, we demonstrate an all-passive 2×4 optical RAM RD with row access operation and subsequent all-passive column decoding to control the access of WDM-formatted words in optical RAM rows. The 2×4 RD exploits a WDM-formatted 2-bit-long memory WordLine address along with its complementary value, all of them encoded on four different wavelengths and broadcasted to all RAM rows. The RD relies on an all-passive wavelength-selective filtering matrix (λ-matrix) that ensures a logical `0' output only at the selected RAM row. Subsequently, the RD output of each row drives the respective SOA-MZI-based Row Access Gate (AG) to grant/block the entry of the incoming data words to the whole memory row. In case of a selected row, the data word exits the row AG and enters the respective CD that relies on an allpassive wavelength-selective Arrayed Waveguide Grating (AWG) for decoding the word bits into their individual columns. Both RD and CD procedures are carried out without requiring any active devices, assuming that the memory address and data word bits as well as their inverted values will be available in their optical form by the CPU interface. Proof-of-concept experimental verification exploiting cascaded pairs of AWGs as the λ-matrix is demonstrated at 10Gb/s, providing error-free operation with a peak power penalty lower than 0.2dB for all optical word channels.

  2. An evaluation of the Exer-Genie exerciser and the Collins pedal mode ergometer for developing physical fitness

    NASA Technical Reports Server (NTRS)

    Olree, H. D.

    1973-01-01

    Experiments that were conducted over a 52-month period showed that isometric and isotonic training on the Exer-Genie gave negligible increases in cardiorespiratory fitness whereas training on the ergometer at a programmed pulse rate increased fitness moderately.

  3. Neutron camera employing row and column summations

    SciTech Connect

    Clonts, Lloyd G.; Diawara, Yacouba; Donahue, Jr, Cornelius; Montcalm, Christopher A.; Riedel, Richard A.; Visscher, Theodore

    2016-06-14

    For each photomultiplier tube in an Anger camera, an R.times.S array of preamplifiers is provided to detect electrons generated within the photomultiplier tube. The outputs of the preamplifiers are digitized to measure the magnitude of the signals from each preamplifier. For each photomultiplier tube, a corresponding summation circuitry including R row summation circuits and S column summation circuits numerically add the magnitudes of the signals from preamplifiers for each row and for each column to generate histograms. For a P.times.Q array of photomultiplier tubes, P.times.Q summation circuitries generate P.times.Q row histograms including R entries and P.times.Q column histograms including S entries. The total set of histograms include P.times.Q.times.(R+S) entries, which can be analyzed by a position calculation circuit to determine the locations of events (detection of a neutron).

  4. Development of a novel eccentric arm cycle ergometer for training the upper body.

    PubMed

    Elmer, Steven J; Danvind, Jonas; Holmberg, Hans-Christer

    2013-01-01

    Several investigators have demonstrated that chronic eccentric leg cycling is an effective method for improving lower body neuromuscular function (e.g., quadriceps muscle size, strength, and mobility) in a variety of patient and athletic populations. To date, there are no reports of using eccentric arm cycling (EC(arm)) as an exercise modality, probably in large part because of the lack of commercially available EC(arm) ergometers. Our purposes for conducting this study were to 1) describe the design and construction of an EC(arm) ergometer and 2) compare EC(arm) to traditional concentric arm cycling (CC(arm)). All of the parts of a Monark 891E cycle ergometer (Monark Exercise AB, Vansbro, Sweden) were removed, leaving the frame and flywheel. An electric motor (2.2 kW) was connected to the flywheel via a pulley and a belt. Motor speed and pedaling rate were controlled by a variable frequency drive. A power meter quantified power and pedaling rate, and provided feedback to the individual. Eight individuals performed 3-min EC(arm) and CC(arm) trials at 40, 80, and 120 W (60 rpm) while VO(2) was measured. The EC(arm) ergometer was simple to use, was adjustable, provided feedback on power output to the user, and allowed for a range of eccentric powers. VO(2) during EC(arm) was substantially lower compared with CC(arm) (P < 0.001). At similar VO(2) (0.97 ± 0.18 vs 0.91 ± 0.09 L·min(-1), for EC(arm) and CC(arm), respectively, P = 0.26), power absorbed during EC(arm) was approximately threefold greater than that produced during CC(arm) (118 ± 1 vs 40 ± 1 W, P < 0.001). This novel EC(arm) ergometer can be used to perform repetitive, high-force, multijoint, eccentric actions with the upper body at a low level of metabolic demand and may allow researchers and clinicians to use EC(arm) as a training and rehabilitation modality.

  5. New algorithm to control a cycle ergometer using electrical stimulation.

    PubMed

    Petrofsky, J S

    2003-01-01

    Data were collected from four male subjects to determine the relationships between load, speed and muscle use during cycle ergometry. These data were then used to construct equations to govern the stimulation of muscle in paralysed individuals, during cycle ergometry induced by functional electrical stimulation (FES) of the quadriceps, gluteus maximus and hamstring muscles. The algorithm was tested on four subjects who were paralysed owing to a complete spinal cord injury between T4 and T11. Using the multivariate equation, the control of movement was improved, and work was accomplished that was double (2940 Nm min(-1) compared with 5880 Nm min(-1)) that of traditional FES cycle ergometry, when muscle stimulation was also controlled by electrical stimulation. Stress on the body, assessed by cardiac output, was increased almost two-fold during maximum work with the new algorithm (81 min(-1) compared with 15 l min(-1) with the new algorithm). These data support the concept that the limitation to workload that a person can achieve on FES cycle ergometry is in the control equations and not in the paralysed muscle.

  6. Dynamic 31P MR spectroscopy of plantar flexion: influence of ergometer design, magnetic field strength (3 and 7 T), and RF-coil design.

    PubMed

    Šedivý, Petr; Kipfelsberger, Monika Christina; Dezortová, Monika; Krššák, Martin; Drobný, Miloslav; Chmelík, Marek; Rydlo, Jan; Trattnig, Siegfried; Hájek, Milan; Valkovič, Ladislav

    2015-04-01

    Dynamic phosphorus magnetic resonance spectroscopy ((31)P MRS) during and after acute exercise enables the noninvasive in vivo determination of the mitochondrial capacity of skeletal muscle. Nevertheless, the lack of standardization in experimental setups leads to significant variations in published values of maximal aerobic capacity, even in the population of healthy volunteers. Thus, in this study, we aimed to assess the impact of the ergometer type (pneumatic and mechanical resistance construction), radiofrequency (RF)-coil diameter, and different magnetic field strengths (3 and 7 T) on the metabolic parameters measured by dynamic (31)P MRS during a plantar flexion isotonic exercise protocol within the same group of healthy volunteers. Dynamic (31)P MRS measurements of the calf muscle in 11 volunteers (mean age, 36  ±  13 yrs; mean BMI, 23.5 ± 2.5 kg/m(2)), on a 3 T MR system with a custom-made mechanical ergometer in the first research laboratory (RL1) and on 3 and 7 T MR systems equipped with a commercial pneumatic ergometer in the second research laboratory (RL2), were performed at three different workloads. RF-coils differed slightly between the sites and MR systems used. The repeatability of the experimental protocol was tested in every setup. The basal concentrations of phosphocreatine (PCr), exercise-induced depletion of PCr (ΔPCr), initial PCr resynthesis rate (VPCr), and mitochondrial capacity (Qmax) were calculated and compared between the research sites and field strengths. High repeatability of the measurement protocol was found in every experimental setup. No significant differences at any workload were found in these metabolic parameters assessed at different magnetic field strengths (3 T vs 7 T), using the same ergometer (in RL2) and a similar RF-coil. In the inter-research laboratory comparison at the same field strength (3 T), but with using different ergometers and RF-coils, differences were found in the concentration of PCr measured at

  7. Mapping wide row crops with video sequences acquired from a tractor moving at treatment speed.

    PubMed

    Sainz-Costa, Nadir; Ribeiro, Angela; Burgos-Artizzu, Xavier P; Guijarro, María; Pajares, Gonzalo

    2011-01-01

    This paper presents a mapping method for wide row crop fields. The resulting map shows the crop rows and weeds present in the inter-row spacing. Because field videos are acquired with a camera mounted on top of an agricultural vehicle, a method for image sequence stabilization was needed and consequently designed and developed. The proposed stabilization method uses the centers of some crop rows in the image sequence as features to be tracked, which compensates for the lateral movement (sway) of the camera and leaves the pitch unchanged. A region of interest is selected using the tracked features, and an inverse perspective technique transforms the selected region into a bird's-eye view that is centered on the image and that enables map generation. The algorithm developed has been tested on several video sequences of different fields recorded at different times and under different lighting conditions, with good initial results. Indeed, lateral displacements of up to 66% of the inter-row spacing were suppressed through the stabilization process, and crop rows in the resulting maps appear straight.

  8. Influence of different length of core suture purchase among suture row on the strength of 6-strand tendon repairs.

    PubMed

    Okubo, Hirotaka; Kusano, Nozomu; Kinjo, Masaki; Kanaya, Fuminori

    2015-01-01

    In multi-strand suture methods consisting of several suture rows, the different length of core suture purchase between each suture row may affect the strength of repairs. We evaluated the influence of the different length of core suture purchase between each suture row on the strength of 6-strand tendon repairs. Rabbit flexor tendons were repaired by using a triple-looped suture technique in which the suture purchase length in each suture row was modified. Group 1, all lengths are 8-mm. Group 2, all lengths are 10-mm. Group 3, two are 10-mm and one is 8-mm. Group 4, one is 10-mm and two are 8-mm. The repaired tendons were subjected to load-to-failure test. The gap strength was significantly greater in Group 1 and Group 2 than in Group 3 and Group 4. This study demonstrates that maintaining equal core suture purchase lengths of each suture row increases the gap resistance.

  9. Estimation of VO2 Max: A Comparative Analysis of Five Exercise Tests.

    ERIC Educational Resources Information Center

    Zwiren, Linda D.; And Others

    1991-01-01

    Thirty-eight healthy females measured maximal oxygen uptake (VO2max) on the cycle ergometer and treadmill to compare five exercise tests (run, walk, step, and two tests using heart-rate response on the bicycle ergometer) in predicting VO2max. Results indicate that walk and run tests are satisfactory predictors of VO2max in 30- to 39-year-old…

  10. Estimation of VO2 Max: A Comparative Analysis of Five Exercise Tests.

    ERIC Educational Resources Information Center

    Zwiren, Linda D.; And Others

    1991-01-01

    Thirty-eight healthy females measured maximal oxygen uptake (VO2max) on the cycle ergometer and treadmill to compare five exercise tests (run, walk, step, and two tests using heart-rate response on the bicycle ergometer) in predicting VO2max. Results indicate that walk and run tests are satisfactory predictors of VO2max in 30- to 39-year-old…

  11. Single-row repair versus double-row repair of full-thickness rotator cuff tears.

    PubMed

    Prasathaporn, Niti; Kuptniratsaikul, Somsak; Kongrukgreatiyos, Kitiphong

    2011-07-01

    The purpose of this meta-analysis was to assess whether there are differences in the outcomes between single-row and double-row rotator cuff repair. Using MEDLINE, SCOPUS, SCIRUS, CINAHL, and the Cochrane Library, as well as a hand search, we searched for articles comparing single-row and double-row rotator cuff repair that were published before September 2009. The controlled clinical studies that met the inclusion and exclusion criteria were assessed for quality of methodology. Two of the authors performed this review and assessment. Any disagreements were resolved by the third author. Three randomized controlled studies and two controlled clinical cohort studies were included in this meta-analysis. These studies were assessed as having a moderate to high level of evidence. The results showed that double-row repair improved tendon healing and provided greater external rotation but with significantly increased operative time. Furthermore, this study found that double-row repair decreased the recurrence rate. However, there were no statistically significant differences found in shoulder function as assessed by Constant score; American Shoulder and Elbow Surgeons (ASES) score; University of California, Los Angeles (UCLA) score; Western Ontario Rotator Cuff (WORC) index; Disabilities of the Arm, Shoulder and Hand (DASH) score; muscle strength; forward flexion; internal rotation; patient satisfaction; return to work; and adverse events. Despite the fact that double-row repair shows a significantly higher rate of tendon healing and greater external rotation than does single-row repair, there is no significant improvement in shoulder function, muscle strength, forward flexion, internal rotation, patient satisfaction, or return to work. Level II, meta-analysis of Level I and Level II studies. Copyright © 2011 Arthroscopy Association of North America. All rights reserved.

  12. Combining ergometer exercise and artificial gravity in a compact-radius centrifuge

    NASA Astrophysics Data System (ADS)

    Diaz, Ana; Trigg, Chris; Young, Laurence R.

    2015-08-01

    Humans experience physiological deconditioning during space missions, primarily attributable to weightlessness. Some of these adverse consequences include bone loss, muscle atrophy, sensory-motor deconditioning, and cardiovascular alteration, which may lead to orthostatic intolerance when astronauts return to Earth. Artificial gravity could provide a comprehensive countermeasure capable of challenging all the physiological systems at once, particularly if combined with exercise, thereby maintaining overall health during extended exposure to weightlessness. A new Compact Radius Centrifuge (CRC) platform was designed and built on the existing Short Radius Centrifuge (SRC) at the Massachusetts Institute of Technology (MIT). The centrifuge has been constrained to a radius of 1.4 m, the upper radial limit for a centrifuge to fit within an International Space Station (ISS) module without extensive structural alterations. In addition, a cycle ergometer has been added for exercise during centrifugation. The CRC now includes sensors of foot forces, cardiovascular parameters, and leg muscle electromyography. An initial human experiment was conducted on 12 subjects to analyze the effects of different artificial gravity levels (0 g, 1 g, and 1.4 g, measured at the feet) and ergometer exercise intensities (25 W warm-up, 50 W moderate and 100 W vigorous) on the musculoskeletal function as well as motion sickness and comfort. Foot forces were measured during the centrifuge runs, and subjective comfort and motion sickness data were gathered after each session. Preliminary results indicate that ergometer exercise on a centrifuge may be effective in improving musculoskeletal function. The combination is well tolerated and motion sickness is minimal. The MIT CRC is a novel platform for future studies of exercise combined with artificial gravity. This combination may be effective as a countermeasure to space physiological deconditioning.

  13. Effects of rehydration and food consumption on salivary flow, pH and buffering capacity in young adult volunteers during ergometer exercise

    PubMed Central

    2013-01-01

    Background The aim of this study was to investigate the influences of rehydration and food consumption on salivary flow, pH, and buffering capacity during bicycle ergometer exercise in participants. Methods Ten healthy volunteers exercised on a bicycle ergometer at 80% of their maximal heart rate. These sessions lasted for two periods of 20 min separated by 5-min rest intervals. Volunteers were subjected to one of the following conditions: (1) no water (mineral water) or food consumption, (2) only water for rehydration, (3) water and food consumption, (4) a sports drink only for rehydration, and (5) rehydration with a sports drink and food. Statistical significance was assessed using one-way analysis of variance and Dunnett’s test (p < 0.05). Results The salivary pH decreased significantly during and after exercise in conditions 4 and 5. The salivary buffering capacity decreased significantly during exercise and/or after the exercise in conditions 1, 3, 4, and 5. Conclusions The results showed that salivary pH and buffering capacity decreased greatly depending on the combination of a sports drink and food. PMID:24160307

  14. Strapping rowers to their sliding seat improves performance during the start of single-scull rowing.

    PubMed

    van Soest, A J Knoek; de Koning, H; Hofmijster, M J

    2016-09-01

    In this study, the effect of strapping rowers to their sliding seat on performance during 75 m on-water starting trials was investigated. Well-trained rowers performed 75 m maximum-effort starts using an instrumented single scull equipped with a redesigned sliding seat system, both under normal conditions and while strapped to the sliding seat. Strapping rowers to their sliding seat resulted in a 0.45 s lead after 75 m, corresponding to an increase in average boat velocity of about 2.5%. Corresponding effect sizes were large. No significant changes were observed in general stroke cycle characteristics. No indications of additional boat heaving and pitching under strapped conditions were found. The increase in boat velocity is estimated to correspond to an increase in average mechanical power output during the start of on-water rowing between 5% and 10%, which is substantial but smaller than the 12% increase found in a previous study on ergometer starting. We conclude that, after a very short period of adaptation to the strapped condition, single-scull starting performance is substantially improved when the rower is strapped to the sliding seat.

  15. Biomechanical Comparison of Arthroscopic Single- and Double-Row Repair Techniques for Acute Bony Bankart Lesions.

    PubMed

    Spiegl, Ulrich J; Smith, Sean D; Todd, Jocelyn N; Coatney, Garrett A; Wijdicks, Coen A; Millett, Peter J

    2014-08-01

    Single- and double-row arthroscopic reconstruction techniques for acute bony Bankart lesions have been described in the literature. The double-row fixation technique would provide superior reduction and stability of a simulated bony Bankart lesion at time zero in a cadaveric model compared with the single-row technique. Controlled laboratory study. Testing was performed on 14 matched pairs of glenoids with simulated bony Bankart fractures with a defect width of 25% of the glenoid diameter. Half of the fractures were repaired with a double-row technique, while the contralateral glenoids were repaired with a single-row technique. The quality of fracture reduction was measured with a coordinate measuring machine. To determine the biomechanical stability of the repairs, specimens were preconditioned with 10 sinusoidal cycles between 5 and 25 N at 0.1 Hz and then pulled to failure in the anteromedial direction at a rate of 5 mm/min. Loads at 1 mm and 2 mm of fracture displacement were determined. The double-row technique required significantly higher forces to achieve fracture displacements of 1 mm (mean, 60.6 N; range, 39.0-93.3 N; P = .001) and 2 mm (mean, 94.4 N; range, 43.4-151.2 N; P = .004) than the single-row technique (1 mm: mean, 30.2 N; range, 14.0-54.1 N and 2 mm: mean, 63.7 N; range, 26.6-118.8 N). Significantly reduced fracture displacement was seen after double-row repair for both the unloaded condition (mean, 1.1 mm; range, 0.3-2.4 mm; P = .005) and in response to a 10-N anterior force applied to the defect (mean, 1.6 mm; range, 0.5-2.7 mm; P = .001) compared with single-row repair (unloaded: mean, 2.1 mm; range, 1.3-3.4 mm and loaded: mean, 3.4 mm; range, 1.9-4.7 mm). The double-row fixation technique resulted in improved fracture reduction and superior stability at time zero in this cadaveric model. This information may influence the surgical technique used to treat large osseous Bankart fractures and the postoperative rehabilitation protocols

  16. Extended abstract: Partial row projection methods

    SciTech Connect

    Bramley, R.; Lee, Y.

    1996-12-31

    Accelerated row projection (RP) algorithms for solving linear systems Ax = b are a class of iterative methods which in theory converge for any nonsingular matrix. RP methods are by definition ones that require finding the orthogonal projection of vectors onto the null space of block rows of the matrix. The Kaczmarz form, considered here because it has a better spectrum for iterative methods, has an iteration matrix that is the product of such projectors. Because straightforward Kaczmarz method converges slowly for practical problems, typically an outer CG acceleration is applied. Definiteness, symmetry, or localization of the eigenvalues, of the coefficient matrix is not required. In spite of this robustness, work has generally been limited to structured systems such as block tridiagonal matrices because unlike many iterative solvers, RP methods cannot be implemented by simply supplying a matrix-vector multiplication routine. Finding the orthogonal projection of vectors onto the null space of block rows of the matrix in practice requires accessing the actual entries in the matrix. This report introduces a new partial RP algorithm which retains advantages of the RP methods.

  17. The use of treadmill ergometers for extensive calculation of external work and leg stiffness during running.

    PubMed

    Avogadro, Patrick; Chaux, Christelle; Bourdin, Muriel; Dalleau, Georges; Belli, Alain

    2004-06-01

    Recently, new treadmill ergometers have been designed to measure the ground reaction forces during numerous successive steps. From ground reaction forces measured in track running, it has been shown to be possible to compute external mechanical work ( W(ext)) and leg stiffness ( k) of a bouncing spring-mass system. However, to the best of our knowledge, there is still no study reporting the inter-stride coefficient of variation (CoV) of W(ext) or k parameters calculated from many successive steps. The aim of this experiment was to investigate the intra-and inter-individual variations of W(ext) and k while running at different speeds on a treadmill ergometer. Thirteen healthy runners ran at 12, 14, 16 and 18 km h(-1) during 3 min. Ground reaction forces were measured and recorded during the last 20 s of each exercise (50-62 steps). From these forces, average values and CoV of W(ext) and k were calculated. W(ext) significantly increased while k decreased with speed (both P<0.001). The mean values of these parameters were in agreement with data already reported and the CoV was less than 6% for all the parameters, showing almost no variation with speed. Therefore, this method of calculation, based on the extensive measurements of ground reaction forces, can be used to extensively study the mechanical parameters of treadmill running, and especially the inter-stride variability.

  18. Dynamic trunk stability is improved in paraplegics following kayak ergometer training.

    PubMed

    Bjerkefors, A; Carpenter, M G; Thorstensson, A

    2007-12-01

    The purpose of the study was to assess whether postural stability in persons with spinal cord injury (SCI) could be affected by training. Ten post-rehabilitated persons with thoracic SCI performed 30 sessions of kayak ergometer training during a 10-week period. The ergometer was modified with a balance module adjustable in the medio-lateral direction. Before and after the training period, horizontal support-surface translations were presented randomly, either in the forward or backward direction, or to the side, while subjects sat in their own wheelchairs. The platform perturbation consisted of an unpredictable initial acceleration, followed by a constant-velocity phase and a predictable deceleration. Markers were applied on the trunk and movement data were recorded in 3D. Four kinematic responses of trunk angular and linear displacement were investigated. In general, postural stability was improved after training with smaller rotational and linear displacements of the trunk observed during both predictable and unpredictable translations in all directions. Thus, the training was able to improve the ability of persons with long-standing SCI to maintain an upright sitting posture in response to externally generated balance perturbations, which should imply an increased capacity to master similar challenges to balance in everyday life.

  19. Pedaling rate is an important determinant of human oxygen uptake during exercise on the cycle ergometer

    PubMed Central

    Formenti, Federico; Minetti, Alberto E; Borrani, Fabio

    2015-01-01

    Estimation of human oxygen uptake () during exercise is often used as an alternative when its direct measurement is not feasible. The American College of Sports Medicine (ACSM) suggests estimating human during exercise on a cycle ergometer through an equation that considers individual's body mass and external work rate, but not pedaling rate (PR). We hypothesized that including PR in the ACSM equation would improve its prediction accuracy. Ten healthy male participants’ (age 19–48 years) were recruited and their steady-state was recorded on a cycle ergometer for 16 combinations of external work rates (0, 50, 100, and 150 W) and PR (50, 70, 90, and 110 revolutions per minute). was calculated by means of a new equation, and by the ACSM equation for comparison. Kinematic data were collected by means of an infrared 3-D motion analysis system in order to explore the mechanical determinants of . Including PR in the ACSM equation improved the accuracy for prediction of sub-maximal during exercise (mean bias 1.9 vs. 3.3 mL O2 kg−1 min−1) but it did not affect the accuracy for prediction of maximal (P > 0.05). Confirming the validity of this new equation, the results were replicated for data reported in the literature in 51 participants. We conclude that PR is an important determinant of human during cycling exercise, and it should be considered when predicting oxygen consumption. PMID:26371230

  20. Determination of aerobic work and power on a rope-braked cycle ergometer by direct measurement.

    PubMed

    Gordon, Rae S; Franklin, Kathryn L; Baker, Julien S; Davies, Bruce

    2006-08-01

    The purpose of this study was to compare the power and work outputs of a cycle ergometer using the manufacturer's guidelines, with calculations using direct flywheel velocity and brake torque. A further aim was to compare the values obtained with those supplied by the manufacturer. A group of 10 male participants were asked to pedal a Monark 824E ergometer at a constant cadence of 60 r/min for a period of 3 min against a resistive mass of 3 kg. The flywheel velocity was measured using a tachometer. The brake force was determined by measuring the tension in the rope on either side of the flywheel. The calculated mean power was 147.45 +/- 6.5 W compared with the Monark value of 183 +/- 3.7 W. The difference between the methods for power estimation was 18% and was statistically significant (p < 0.01). The mean work done by the participants during the 3 min period was found to be 26 460 +/- 1145 J compared with the Monark value of 33,067 +/- 648 J (p < 0.01). The Monark formulae currently used to determine the power and work done by a participant overestimates the actual values required to overcome the resistance. There findings have far-reaching implications in the physiological assessment of athletic, sedentary, and diseased populations.

  1. Neuromuscular control of a single twitch muscle in wild type and mutant Drosophila, measured with an ergometer.

    PubMed

    Harvey, Jennifer; Brunger, Holly; Middleton, C Adam; Hill, Julia A; Sevdali, Maria; Sweeney, Sean T; Sparrow, John C; Elliott, Christopher J H

    2008-06-01

    How do deficits in neuronal growth, aging or synaptic function affect the final, mechanical output of a single muscle twitch? We address this in vivo (indeed in situ) with a novel ergometer that records the output of a large specialised muscle, the Drosophila jump muscle. Here, we describe in detail the ergometer, its construction and use. We evaluated the ergometer by showing that adult fly jump muscle output varies little between 3 h and 7 days; but newly eclosed flies produce only 65%. In a mutant with little octopamine (Tbetah), jump muscle performance is reduced by 28%. The initial responses of synaptic growth mutants (highwire and spinster) do not differ from wild type, as expected on the homeostatic hypothesis. However, responses in highwire mutations gradually decline following repeated stimuli, suggesting physiological as well as anatomical abnormalities. We conclude that the assay is robust, sensitive and reliable with a good throughput.

  2. Functional Outcomes After Double-Row Versus Single-Row Rotator Cuff Repair

    PubMed Central

    Nicholas, Stephen J.; Lee, Steven J.; Mullaney, Michael J.; Tyler, Timothy F.; Fukunaga, Takumi; Johnson, Christopher D.; McHugh, Malachy P.

    2016-01-01

    Background: The functional benefits of double-row (DR) versus single-row (SR) rotator cuff repair are not clearly established. Purpose: To examine the effect of DR versus SR rotator cuff repair on functional outcomes and strength recovery in patients with full-thickness tears. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: Forty-nine patients were randomized to DR or SR repairs; 36 patients (13 women, 23 men; mean age, 62 ± 7 years; 20 SR, 16 DR) were assessed at a mean 2.2 ± 1.6 years after surgery (range, 1-7 years; tear size: 17 medium, 13 large, 9 massive). The following data were recorded prior to surgery and at follow-up: Penn shoulder score, American Shoulder and Elbow Surgeons (ASES), and Simple Shoulder Test (SST) results; range of motion (ROM) for shoulder flexion, external rotation (ER) at 0° and 90° of abduction, and internal rotation (IR) at 90° of abduction; and shoulder strength (Lafayette manual muscle tester) in empty- and full-can tests, abduction, and ER at 0° of abduction. Treatment (SR vs DR) × time (pre- vs postoperative) mixed-model analysis of variance was used to assess the effect of rotator cuff repair. Results: Rotator cuff repair markedly improved Penn, ASES, and SST scores (P < .001), with similar improvement between SR and DR repairs (treatment × time, P = .38-.10) and excellent scores at follow-up (DR vs SR: Penn, 91 ± 11 vs 92 ± 11 [P = .73]; ASES, 87 ± 12 vs 92 ± 12 [P = .21]; SST, 11.4 ± 1.0 vs 11.3 ± 1.0 [P = .76]). Patients with DR repairs lost ER ROM at 0° of abduction (preoperative to final follow-up, 7° ± 10° loss [P = .013]). ER ROM did not significantly change with SR repair (5° ± 14° gain, P = .16; treatment by time, P = .008). This effect was not apparent for ER ROM at 90° of abduction (treatment × time, P = .26). IR ROM improved from preoperative to final follow-up (P < .01; SR, 17° ± 27°; DR, 7° ± 21°; treatment × time, P = .23). Rotator cuff repair markedly

  3. Early rehabilitation using a passive cycle ergometer on muscle morphology in mechanically ventilated critically ill patients in the Intensive Care Unit (MoVe-ICU study): study protocol for a randomized controlled trial.

    PubMed

    dos Santos, Laura Jurema; de Aguiar Lemos, Fernando; Bianchi, Tanara; Sachetti, Amanda; Dall' Acqua, Ana Maria; da Silva Naue, Wagner; Dias, Alexandre Simões; Vieira, Silvia Regina Rios

    2015-08-28

    Patients in Intensive Care Units (ICU) are often exposed to prolonged immobilization which, in turn, plays an important role in neuromuscular complications. Exercise with a cycle ergometer is a treatment option that can be used to improve the rehabilitation of patients on mechanical ventilation (MV) in order to minimize the harmful effects of immobility. A single-blind randomized controlled trial (the MoVe ICU study) will be conducted to evaluate and compare the effects of early rehabilitation using a bedside cycle ergometer with conventional physical therapy on the muscle morphology of the knee extensors and diaphragm in critical ill patients receiving MV. A total of 28 adult patients will be recruited for this study from among those admitted to the intensive care department at the Hospital de Clínicas de Porto Alegre. Eligible patients will be treated with MV from a period of 24 to 48 h, will have spent maximum of 1 week in hospital and will not exhibit any characteristics restricting lower extremity mobility. These subjects will be randomized to receive either conventional physiotherapy or conventional physiotherapy with an additional cycle ergometer intervention. The intervention will be administered passively for 20 min, at 20 revolutions per minute (rpm), once per day, 7 days a week, throughout the time the patients remain on MV. Outcomes will be cross-sectional quadriceps thickness, length of fascicle, pennation angle of fascicles, thickness of vastus lateralis muscle, diaphragm thickness and excursion of critical ICU patients on MV measured with ultrasound. The MoVe-ICU study will be the first randomized controlled trial to test the hypothesis that early rehabilitation with a passive cycle ergometer can preserve the morphology of knee extensors and diaphragm in critical patients on MV in ICUs. NCT02300662 (25 November 2014).

  4. Limitations of Spectral Electromyogramic Analysis to Determine the Onset of Neuromuscular Fatigue Threshold during Incremental Ergometer Cycling

    PubMed Central

    Latasa, Iban; Cordova, Alfredo; Malanda, Armando; Navallas, Javier; Lavilla-Oiz, Ana; Rodriguez-Falces, Javier

    2016-01-01

    Recently, a new method has been proposed to detect the onset of neuromuscular fatigue during an incremental cycling test by assessing the changes in spectral electromyographic (sEMG) frequencies within individual exercise periods of the test. The method consists on determining the highest power output that can be sustained without a significant decrease in spectral frequencies. This study evaluated the validity of the new approach by assessing the changes in spectral indicators both throughout the whole test and within individual exercise periods of the test. Fourteen cyclists performed incremental cycle ergometer rides to exhaustion with bipolar surface EMG signals recorded from the vastus lateralis. The mean and median frequencies (Fmean and Fmedian, respectively) of the sEMG power spectrum were calculated. The main findings were: (1) Examination of spectral indicators within individual exercise periods of the test showed that neither Fmean nor Fmedian decreased significantly during the last (most fatiguing) exercise periods. (2) Examination of the whole incremental test showed that the behaviour of Fmean and Fmedian with increasing power output was highly inconsistent and varied greatly among subjects. (3) Over the whole incremental test, half of the participants exhibited a positive relation between spectral indicators and workload, whereas the other half demonstrated the opposite behavior. Collectively, these findings indicate that spectral sEMG indexes do not provide a reliable measure of the fatigue state of the muscle during an incremental cycling test. Moreover, it is concluded that it is not possible to determine the onset of neuromuscular fatigue during an incremental cycling test by examining spectral indicators within individual exercise periods of the test. Key points The behaviour of spectral EMG indicators during the incremental test exhibited a high heterogeneity among individuals, with approximately half of the participants showing a positive

  5. Limitations of Spectral Electromyogramic Analysis to Determine the Onset of Neuromuscular Fatigue Threshold during Incremental Ergometer Cycling.

    PubMed

    Latasa, Iban; Cordova, Alfredo; Malanda, Armando; Navallas, Javier; Lavilla-Oiz, Ana; Rodriguez-Falces, Javier

    2016-03-01

    Recently, a new method has been proposed to detect the onset of neuromuscular fatigue during an incremental cycling test by assessing the changes in spectral electromyographic (sEMG) frequencies within individual exercise periods of the test. The method consists on determining the highest power output that can be sustained without a significant decrease in spectral frequencies. This study evaluated the validity of the new approach by assessing the changes in spectral indicators both throughout the whole test and within individual exercise periods of the test. Fourteen cyclists performed incremental cycle ergometer rides to exhaustion with bipolar surface EMG signals recorded from the vastus lateralis. The mean and median frequencies (Fmean and Fmedian, respectively) of the sEMG power spectrum were calculated. The main findings were: (1) Examination of spectral indicators within individual exercise periods of the test showed that neither Fmean nor Fmedian decreased significantly during the last (most fatiguing) exercise periods. (2) Examination of the whole incremental test showed that the behaviour of Fmean and Fmedian with increasing power output was highly inconsistent and varied greatly among subjects. (3) Over the whole incremental test, half of the participants exhibited a positive relation between spectral indicators and workload, whereas the other half demonstrated the opposite behavior. Collectively, these findings indicate that spectral sEMG indexes do not provide a reliable measure of the fatigue state of the muscle during an incremental cycling test. Moreover, it is concluded that it is not possible to determine the onset of neuromuscular fatigue during an incremental cycling test by examining spectral indicators within individual exercise periods of the test. Key pointsThe behaviour of spectral EMG indicators during the incremental test exhibited a high heterogeneity among individuals, with approximately half of the participants showing a positive

  6. Is three-dimensional anthropometric analysis as good as traditional anthropometric analysis in predicting junior rowing performance?

    PubMed

    Schranz, Natasha; Tomkinson, Grant; Olds, Tim; Petkov, John; Hahn, Allan G

    2012-01-01

    With the use of three-dimensional whole body scanning technology, this study compared the 'traditional' anthropometric model [one-dimensional (1D) measurements] to a 'new' model [1D, two-dimensional (2D), and three-dimensional (3D) measurements] to determine: (1) which model predicted more of the variance in self-reported best 2000-m ergometry rowing performance; and (2) what were the best anthropometric predictors of ergometry performance, for junior rowers competing at the 2007 and 2008 Australian Rowing Championships. Each rower (257 females, 16.3 ± 1.4 years and 243 males, 16.6 ± 1.5 years) completed a performance and demographic questionnaire, had their mass, standing and sitting height physically measured and were landmarked and scanned using the Vitus Smart® 3D whole body scanner. Absolute and proportional anthropometric measurements were extracted from the scan files. Partial least squares regression analysis, with anthropometric measurements and age as predictor variables and self-reported best 2000-m ergometer time as the response variable, was used to first compare the two models and then to determine the best performance predictors. The variance explained by each model was similar for both male [76.1% (new) vs. 73.5% (traditional)] and female [72.3% (new) vs. 68.6% (traditional)] rowers. Overall, absolute rather than proportional measurements, and 2D and 3D rather than 1D measurements, were the best predictors of rowing ergometry performance, with whole body volume and surface area, standing height, mass and leg length the strongest individual predictors.

  7. Remote sensing of row crop structure and component temperatures using directional radiometric temperatures and inversion techniques

    NASA Technical Reports Server (NTRS)

    Kimes, D. S.

    1983-01-01

    A physically based sensor response model of a row crop was used as the mathematical framework from which several inversion strategies were tested for extracting row structure information and component temperatures using a series of sensor view angles. The technique was evaluated on ground-based radiometric thermal infrared data of a cotton row crop that covered 48 percent of the ground in the vertical projection. The results showed that the accuracies of the predicted row heights and widths, vegetation temperatures, and soil temperatures of the cotton row crop were on the order of 5 cm, 1 deg, and 2 deg C, respectively. The inversion techniques can be applied to directional sensor data from aircraft platforms and even space platforms if the effects of atmospheric absorption and emission can be corrected. In theory, such inversion techniques can be applied to a wide variety of vegetation types and thus can have significant implications for remote sensing research and applications in disciplines that deal with incomplete vegetation canopies.

  8. Built for rowing: frog muscle is tuned to limb morphology to power swimming

    PubMed Central

    Richards, Christopher T.; Clemente, Christofer J.

    2013-01-01

    Rowing is demanding, in part, because drag on the oars increases as the square of their speed. Hence, as muscles shorten faster, their force capacity falls, whereas drag rises. How do frogs resolve this dilemma to swim rapidly? We predicted that shortening velocity cannot exceed a terminal velocity where muscle and fluid torques balance. This terminal velocity, which is below Vmax, depends on gear ratio (GR = outlever/inlever) and webbed foot area. Perhaps such properties of swimmers are ‘tuned’, enabling shortening speeds of approximately 0.3Vmax for maximal power. Predictions were tested using a ‘musculo-robotic’ Xenopus laevis foot driven either by a living in vitro or computational in silico plantaris longus muscle. Experiments verified predictions. Our principle finding is that GR ranges from 11.5 to 20 near the predicted optimum for rowing (GR ≈ 11). However, gearing influences muscle power more strongly than foot area. No single morphology is optimal for producing muscle power. Rather, the ‘optimal’ GR decreases with foot size, implying that rowing ability need not compromise jumping (and vice versa). Thus, despite our neglect of additional forces (e.g. added mass), our model predicts pairings of physiological and morphological properties to confer effective rowing. Beyond frogs, the model may apply across a range of size and complexity from aquatic insects to human-powered rowing. PMID:23676897

  9. Optimization of oar blade design for improved performance in rowing.

    PubMed

    Caplan, Nicholas; Gardner, Trevor N

    2007-11-01

    The aim of the present study was to find a more optimal blade design for rowing performance than the Big Blade, which has been shown to be less than optimal for propulsion. As well as the Big Blade, a flat Big Blade, a flat rectangular blade, and a rectangular blade with the same curvature and projected area as the Big Blade were tested in a water flume to determine their fluid dynamic characteristics at the full range of angles at which the oar blade might present itself to the water. Similarities were observed between the flat Big Blade and rectangular blades. However, the curved rectangular blade generated significantly more lift in the angle range 0-90 degrees than the curved Big Blade, although it was similar between 90 and 180 degrees. This difference was attributed to the shape of the upper and lower edges of the blade and their influence on the fluid flow around the blade. Although the influence of oar blade design on boat speed was not investigated here, the significant increases in fluid force coefficients for the curved rectangular blade suggest that this new oar blade design could elicit a practically significant improvement in rowing performance.

  10. Blade row interaction effects on flutter and forced response

    NASA Technical Reports Server (NTRS)

    Buffum, Daniel H.

    1993-01-01

    In the flutter or forced response analysis of a turbomachine blade row, the blade row in question is commonly treated as if it is isolated from the neigboring blade rows. Disturbances created by vibrating blades are then free to propagate away from this blade row without being disturbed. In reality, neighboring blade rows will reflect some portion of this wave energy back toward the vibrating blades, causing additional unsteady forces on them. It is of fundamental importance to determine whether or not these reflected waves can have a significant effect on the aeroelastic stability or forced response of a blade row. Therefore, a procedure to calculate intra-blade-row unsteady aerodynamic interactions was developed which relies upon results available from isolated blade row unsteady aerodynamic analyses. In addition, an unsteady aerodynamic influence coefficient technique is used to obtain a model for the vibratory response in which the neighboring blade rows are also flexible. The flutter analysis shows that interaction effects can be destabilizing, and the forced response analysis shows that interaction effects can result in a significant increase in the resonant response of a blade row.

  11. Effect of inspiratory muscle warm-up on submaximal rowing performance.

    PubMed

    Arend, Mati; Mäestu, Jarek; Kivastik, Jana; Rämson, Raul; Jürimäe, Jaak

    2015-01-01

    Performing inspiratory muscle warm-up might increase exercise performance. The aim of this study was to investigate the impact of inspiratory muscle warm-up to submaximal rowing performance and to find if there is an effect on lactic acid accumulation and breathing parameters. Ten competitive male rowers aged between 19 and 27 years (age, 23.1 ± 3.8 years; height, 188.1 ± 6.3 cm; body mass, 85.6 ± 6.6 kg) were tested 3 times. During the first visit, maximal inspiratory pressure (MIP) assessment and the incremental rowing test were performed to measure maximal oxygen consumption and maximal aerobic power (Pamax). A submaximal intensity (90% Pamax) rowing test was performed twice with the standard rowing warm-up as test 1 and with the standard rowing warm-up and specific inspiratory muscle warm-up as test 2. During the 2 experimental tests, distance, duration, heart rate, breathing frequency, ventilation, peak oxygen consumption, and blood lactate concentration were measured. The only value that showed a significant difference between the test 1 and test 2 was breathing frequency (52.2 ± 6.8 vs. 53.1 ± 6.8, respectively). Heart rate and ventilation showed a tendency to decrease and increase, respectively, after the inspiratory muscle warm-up (p < 0.1). Despite some changes in respiratory parameters, the use of 40% MIP intensity warm-up is not suggested if the mean intensity of the competition is at submaximal level (at approximately 90% maximal oxygen consumption). In conclusion, the warm-up protocol of the respiratory muscles used in this study does not have a significant influence on submaximal endurance performance in highly trained male rowers.

  12. Hand Replantation with Proximal Row Carpectomy

    PubMed Central

    Lee, Young-Keun; Lee, Hang-Ho; Park, Ji-Kang; Kim, Joo-Yong; Dhawan, Vikas

    2008-01-01

    The purpose of this study is to present our operative technique and postoperative results of the hand replantation with proximal row carpectomy in cases of complete amputation at the level of wrist joint. From May 2003 to April 2005, five patients suffered from complete amputation of the hand due to industrial trauma. Amputation level was radiocarpal joint in three cases and midcarpal joint in two cases. Three cases represented guillotine type and two cases with local crush type injuries. All were men and the mean age was 26.6 years. The mean follow-up period was 26.8 months. At the time of replantation, the wrist joint was stabilized with transarticular fixation using three to four Kirschner’s wires after performing proximal row carpectomy. Postoperatively, functional results such as muscle strength, range of motion of the wrist and fingers, and sensory recovery were assessed according to Chen’s criteria. Joint width and arthritic changes of the radio-capitate joint were evaluated with radiologic tools. According to Chen’s criteria, the overall results in five cases were classified as grade II. Intrinsic muscle power of hands was found to be grade 4. The mean grip and pinch powers were 41% and 45%, respectively, compared to contralateral hand. The mean arc of flexion–extension of wrist was 53°. Total mean active motion of fingers was 215 degrees. Static two-point discrimination of fingertip ranged from 8 to 13 mm. On the follow-up, computerized tomography showed well-preserved radio-capitate joint space without any arthritic changes. While performing hand replantation after amputation at the radiocarpal or midcarpal level, proximal row carpectomy is a useful procedure to preserve joint motion of the wrist in selected cases. PMID:18855073

  13. Determination of the neutron flux for the Yankee Rowe experiment in the Ford Nuclear Reactor

    SciTech Connect

    Cacciapouti, R.J.; Petrusha, L.

    1994-12-31

    Yankee Atomic Electric Company undertook a Test Irradiation Program at the Ford Nuclear Reactor of the University of Michigan. The program was implemented to characterize the irradiation response of representative Yankee Rowe reactor vessel beltline plate materials. The program was also intended to remove uncertainties in the existing reactor vessel fluence and damage predictions on the Yankee Rowe reactor vessel steel. Since this is the first in-core experiment of this type for the Ford Nuclear Reactor, the measurement of the reaction rate and the estimate of the fluence are presented.

  14. External And Internal Work Of A T-6 Paraplegic Propelling A Wheelchair And Arm Cranking A Cycle Ergometer: Case Study

    NASA Astrophysics Data System (ADS)

    Novak, Charles W.

    1982-02-01

    In this, the International Year of the Disabled, attention is directed among other areas toward rehabilitation and sports participation of wheelchair users. As an application of movement analysis in medicine and rehabilitation and as an application of sports research using biomechanics, this investigation was performed to compare the results of two methods of gathering data on the stress of wheelchair propelling at equivalent work loads and to account for differences in physiological responses with a mechanical analysis of wheelchair propelling. Physiological data collected were heart rate, systolic blood pressure, and rate-pressure product. A biomechanical cinematography analysis was used to determine external work in wheelchair propelling and to determine the extent to which modifications in segment actionsoccurred during increasing magnitude of work. A cycle ergometer was adjusted to replicate external work loads performed during wheelchair propelling. A t-test of equivalent external work loads indicated that heart rate was not different between the two exercise modes at the .05 level of significance. The t-test did indicate a significant difference in systolic blood pressure and rate-pressure product at the .05 level of significance. The biomechanical analysis of wheelchair propelling established that an increase in external work was accomplished by a decrease in the range of motion and an increase in the speed of movement. During cycle ergometry the range and speed of movement remained the same while resistance was increased. Results of the study established that while heart rate for equivalent external work loads was the same for wheelchair propelling and arm cranking cycle ergometry, systolic blood pressure and rate-pressure product were not the same. The suggestion was that some means of propelling a wheelchair other than that which is con-sidered "standard" might be considered which produces less stressful responses in wheelchair users.

  15. The motor-learning process of older adults in eccentric bicycle ergometer training.

    PubMed

    Purtsi, Jarno; Vihko, Veikko; Kankaanpää, Anna; Havas, Eino

    2012-07-01

    This study describes the motor-learning process of older individuals during the course of a training intervention on a motor-driven eccentric bicycle ergometer. Seventeen women and 16 men (64 ± 6 yr) took part in a 10-wk training program. Uniformity of force production and consistency of timing were used to describe their motor performance. The results suggested that participants improved the coefficient of variation of peak force during the intervention (measured at the 2nd, 4th, 6th, 8th, 10th, 12th, and the 18th training sessions). They reached a fairly constant level of motor performance around the 12th training session (5 wk). Age and sex affected improvements in the early phases of the learning process to an extent, but the differences diminished by the end of the intervention. These results suggest that the force control of continuous eccentric muscle contractions improves as a result of training in older adults.

  16. Ergometer within a whole-body plethysmograph to evaluate performance of guinea pigs under toxic atmospheres

    SciTech Connect

    Malek, D.E.; Alarie, Y. )

    1989-11-01

    A guinea pig ergometer was constructed within an enclosure, with inlet and outlet ports for continuous ventilation, designed so that the enclosure would work as a whole-body plethysmograph as well as an inhalation exposure chamber. This system provided continuous measurement of tidal volume, respiratory frequency, oxygen uptake, and carbon dioxide output which enabled an evaluation of performance in terms of distance traveled over time with the animals running at a known speed and constant oxygen uptake. The effects of CO or HCl in running versus sedentary animals were investigated using this apparatus. For CO, exercise increased the rapidity of the onset of incapacitation as would be predicted by the increase in metabolic rate. HCl produced a more severe incapacitating effect in exercising animals that was out of proportion with the increase in minute volume induced by exercise.

  17. Use of the Wattbike Cycle Ergometer for Attenuation of Bilateral Pedaling Asymmetry in Trained Cyclists.

    PubMed

    Kell, David T; Greer, Beau K

    2017-02-01

    Kell, DT and Greer, BK. Use of the Wattbike cycle ergometer for attenuation of bilateral pedaling asymmetry in trained cyclists. J Strength Cond Res 31(2): 468-473, 2017-Experienced cyclists typically pedal with a 5-20% bilateral asymmetry in regards to power output. The aim of this study was to determine if visual feedback (VF) through the Wattbike cycle ergometer is an effective tool in reducing bilateral pedaling asymmetry in trained cyclists. Twelve subjects completed three 10-minute cycling trials on the Wattbike at a power output consistent with 60% V[Combining Dot Above]O2 peak. The 3 trials consisted of a baseline (BASE) trial in which cyclists pedaled without instruction, a conscious control (CC) trial during which cyclists attempted to pedal symmetrically, and another trial in which cyclists attempted to pedal symmetrically while using VF of their bilateral power outputs (%) through the Wattbike. Although the BASE trial was always performed first, the order of the CC and VF trials was counterbalanced to minimize the influence of the order effect. For the primary analysis, the Asymmetry Index percentages (AI%s) for the 3 trials were not significantly different (p > 0.05). However, secondary analysis of subjects who had baseline AI%s within the normal, reported range showed significantly decreased AI%s during the VF trial as compared with BASE (p ≤ 0.05). These results suggest that cyclists with normal AI%s can pedal more symmetrically while using VF of their asymmetry as opposed to merely attempting conscious correction without feedback. It is currently unknown whether adopting a more bilaterally symmetrical pedaling style will improve cycling performance or decrease injury rates in cyclists.

  18. Pedaling rate is an important determinant of human oxygen uptake during exercise on the cycle ergometer.

    PubMed

    Formenti, Federico; Minetti, Alberto E; Borrani, Fabio

    2015-09-01

    Estimation of human oxygen uptake (V˙o2) during exercise is often used as an alternative when its direct measurement is not feasible. The American College of Sports Medicine (ACSM) suggests estimating human V˙o2 during exercise on a cycle ergometer through an equation that considers individual's body mass and external work rate, but not pedaling rate (PR). We hypothesized that including PR in the ACSM equation would improve its V˙o2 prediction accuracy. Ten healthy male participants' (age 19-48 years) were recruited and their steady-state V˙o2 was recorded on a cycle ergometer for 16 combinations of external work rates (0, 50, 100, and 150 W) and PR (50, 70, 90, and 110 revolutions per minute). V˙o2 was calculated by means of a new equation, and by the ACSM equation for comparison. Kinematic data were collected by means of an infrared 3-D motion analysis system in order to explore the mechanical determinants of V˙o2. Including PR in the ACSM equation improved the accuracy for prediction of sub-maximal V˙o2 during exercise (mean bias 1.9 vs. 3.3 mL O2 kg(-1) min(-1)) but it did not affect the accuracy for prediction of maximal V˙o2 (P > 0.05). Confirming the validity of this new equation, the results were replicated for data reported in the literature in 51 participants. We conclude that PR is an important determinant of human V˙o2 during cycling exercise, and it should be considered when predicting oxygen consumption. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  19. Registration of ‘Lyon’, a two-row, spring feed barley

    USDA-ARS?s Scientific Manuscript database

    ‘Lyon’ (Reg. No. CV-356, PI 673045), a spring, two-row, hulled feed barley (Hordeum vulgare L.) cultivar developed and tested as 05WA-316.K, was released in 2013 by Washington State University (WSU). Lyon was derived from the cross ‘Baronesse’/‘Spaulding’ and selected through single-seed descent fro...

  20. 97. VIEW OF CENTER OF INTERIOR ROW OF EQUIPMENT CABINETS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    97. VIEW OF CENTER OF INTERIOR ROW OF EQUIPMENT CABINETS ON SOUTH SIDE OF LANDLINE INSTRUMENTATION ROOM. THREE ADDITIONAL GOULD BRUSH CHART RECORDERS ARE IN THIS ROW (NOT VISIBLE IN PHOTOGRAPH) LOCATED IMMEDIATELY EAST (LEFT) OF THESE CABINETS. Another row of cabinets south of (behind) this one is not accessible for photography. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  1. Compact Spare-Row Decoder For Computer Memory

    NASA Technical Reports Server (NTRS)

    Katz, Richard B.; Rakow, Glenn P.; Bickler, Thomas C.; Barto, Rod

    1992-01-01

    Spare-row memory-address-decoder circuit commanded to address ninth row in computer memory instead of addressing one of eight others it would address normally. Variants used to construct small, highly reliable computers. Spare-row decoder offers advantages of compactness, efficiency, and performance. Requires only 12.5 percent memory overhead. System equipped with spare-row decoder requires less glue logic and exhibits greater through-put. Applications include computers in Hitchhiker Central Unit embedded computer on Cassini spacecraft. Concept of circuit applicable to most flight computer systems.

  2. The influence of the rotational energy of a flywheel on the load pulse sum during pedalling on a cycle ergometer.

    PubMed

    Voigt, B; von Kiparski, R

    1989-01-01

    Employing seven male subjects, the influence of four different ergometer flywheels with the moments of inertia at the crankshaft (J') = 5.5, 10.5, 16.5, and 19.5 kg.m2 on 6-min load pulse sum (LPS), the heart rate integrated over 6-min was investigated. The J' was demonstrated to influence LPS at each of the corresponding rotational energies of the flywheels (75, 144, 226 and 276 J at 50 rev.min-1) in the four work-load steps (50, 100, 150 and 200 W). Between the values J' = 5.5 kg.m2 and 10.5 kg.m2 the LPS decreases, to rise again in the range J' = 10.5 kg.m2-19.5 kg.m2. For equal work-loads the minimum LPS was reached at a J' of 10.5 kg.m2. For the workloads of 100, 150 and 200 W it was possible to show statistically significant differences. The moment of inertia of ergometer flywheels J has a smoothing effect on the fluctuations of the rotational speed which are unavoidable during work on a cycle ergometer. The flywheel stores the leg forces acting on the pedals as rotational energy and opposes any rotational acceleration. If the J used is too small, equalization of the fluctuations of the rotational speed remains unsatisfactory. Flywheels with larger J require larger torques at the crankshaft for acceleration. For the most effective delivery of work to a cycle ergometer, an optimal rotational energy of the flywheel was found. For equal physical work, smaller or larger rotational energies require a larger expenditure of biological energy. A J' = 11 +/- 2 kg.m2 was incorporated into the draft for the German standard DIN 13,405 -- cycle-type ergometers.

  3. Comparison of forearm blood flow responses to incremental handgrip and cycle ergometer exercise: relative contribution of nitric oxide

    PubMed Central

    Green, Daniel J; Bilsborough, William; Naylor, Louise H; Reed, Chris; Wright, Jeremy; O'Driscoll, Gerry; Walsh, Jennifer H

    2005-01-01

    The contribution of endothelium-derived nitric oxide (NO) to exercise hyperaemia remains controversial. Disparate findings may, in part, be explained by different shear stress stimuli as a result of different types of exercise. We have directly compared forearm blood flow (FBF) responses to incremental handgrip and cycle ergometer exercise in 14 subjects (age ± s.e.m.) using a novel software system which calculates conduit artery blood flow continuously across the cardiac cycle by synchronising automated edge-detection and wall tracking of high resolution B-mode arterial ultrasound images and Doppler waveform envelope analysis. Monomethyl arginine (l-NMMA) was infused during repeat bouts of each incremental exercise test to assess the contribution of NO to hyperaemic responses. During handgrip, mean FBF increased with workload (P < 0.01) whereas FBF decreased at lower cycle workloads (P < 0.05), before increasing at 120 W (P < 0.001). Differences in these patterns of mean FBF response to different exercise modalities were due to the influence of retrograde diastolic flow during cycling, which had a relatively larger impact on mean flows at lower workloads. Retrograde diastolic flow was negligible during handgrip. Although mean FBF was lower in response to cycling than handgrip exercise, the impact of l–NMMA was significant during the cycle modality only (P < 0.05), possibly reflecting the importance of an oscillatory antegrade/retrograde flow pattern on shear stress-mediated release of NO from the endothelium. In conclusion, different types of exercise present different haemodynamic stimuli to the endothelium, which may result in differential effects of shear stress on the vasculature. PMID:15513940

  4. A Front-Row Seat at a Wheelchair Crash Test: EP Kicks Off Its Wheelchair Transportation Safety Series with a Visit to the University of Michigan's Transportation Research Institute

    ERIC Educational Resources Information Center

    Hollingsworth, Jan Carter

    2007-01-01

    The centerpiece of the University of Michigan's Transportation Research Institute (UMTRI) Sled Lab is "the impact sled," as it is called in the business. It's the business of conducting sled impact tests, perhaps better known as crash tests, on all types of wheelchairs and wheelchair seating systems as well as wheelchair tiedowns and…

  5. A Front-Row Seat at a Wheelchair Crash Test: EP Kicks Off Its Wheelchair Transportation Safety Series with a Visit to the University of Michigan's Transportation Research Institute

    ERIC Educational Resources Information Center

    Hollingsworth, Jan Carter

    2007-01-01

    The centerpiece of the University of Michigan's Transportation Research Institute (UMTRI) Sled Lab is "the impact sled," as it is called in the business. It's the business of conducting sled impact tests, perhaps better known as crash tests, on all types of wheelchairs and wheelchair seating systems as well as wheelchair tiedowns and…

  6. Paired vehicle occupant analysis indicates age and crash severity moderate likelihood of higher severity injury in second row seated adults in frontal crashes.

    PubMed

    Atkinson, T; Gawarecki, L; Tavakoli, M

    2016-04-01

    The majority of advances in occupant protection systems for motor vehicle occupants have focused on occupants seated in the front row of the vehicle. Recent studies suggest that these systems have resulted in lower injury risk for front row occupants as compared to those in the second row. However, these findings are not universal. In addition, some of these findings result from analyses that compare groups of front and second row occupants exposed to dissimilar crash conditions, raising questions regarding whether they might reflect differences in the crash rather than the front and second row restraint systems. The current study examines factors associated with injury risk for pairs of right front seat and second row occupants in frontal crashes in the United States using paired data analysis techniques. These data indicate that the occupant seated in the front row frequently experiences the more severe injury in the pair, however there were no significant differences in the rate of occurrence of these events and events where the more severe injury occurs in the second row occupant of the pair. A logistic regression indicated that the likelihood of the more severe injury occurring in the second row seated occupant of the pair increased as crash severity increased, consistent with data from anatomic test dummy (ATD) tests. It also indicated that the second row occupant was more likely to have the more severe injury in the pair if that occupant was the older occupant of the pair. These findings suggest that occupant protection systems which focus on providing protection specifically for injuries experienced by older occupants in the second row in higher severity crash conditions might provide the greatest benefit.

  7. Automated Data Collection and Processing for a Concentric/Eccentric Cycle Ergometer,

    DTIC Science & Technology

    1986-02-01

    A/D converter samples from the 7 cycle transducers. The list values are not in meaningful units of force or angle but in " machine units", values from...The calibration factors are used to convert machine unit values to newtons and radians. There are 100 rows of transducer data in a file for each cycle...smoothing is required. Calibration factors are used to convert machine units corresponding to normal and frictional forces from each pedal into newtons

  8. Selective Changes on the Mechanical Capacities of Lower Body Muscles After a Cycle Ergometer Sprint Training Against Heavy and Light Resistances.

    PubMed

    García-Ramos, Amador; Torrejón, Alejandro; Pérez-Castilla, Alejandro; Morales-Artacho, Antonio J; Jaric, Slobodan

    2017-06-28

    This study explored the feasibility of the linear force-velocity (F-V) modelling approach to detect selective changes of the F-V parameters (i.e., maximum force [F0], maximum velocity [V0], F-V slope [a], and maximum power [P0]) following a sprint training program. Twenty-seven men were randomly assigned to a heavy load group (HLG), light load group (LLG), or control group (CG). The training sessions (6 weeks × 2 sessions per week) comprised performing eight maximal effort sprints against either heavy (HLG) or light (LLG) resistances in the leg cycle ergometer exercise. Pre- and posttest consisted of the same task performed against four different resistances that allowed the determination of the F-V parameters through the application of the multiple-point method (four resistances used for the F-V modelling) and the recently proposed two-point method (only the two distant resistances used). Both the multiple-point and the two-point methods revealed a high reliability (all coefficient of variation [CV] < 5% and intraclass correlation coefficients [ICC] > 0.80) while being also able to detect the group-specific training-related changes. Large increments of F0, a, and P0 were observed in HLG compared to LLG and CG (Effect size [ES] = 1.29-2.02). Moderate increments of V0 were observed in LLG compared to HLG and CG (ES = 0.87-1.15). A short-term sprint training on a leg cycle ergometer induces specific changes on the F-V parameters that can be accurately monitored by applying just two distinctive resistances during routine testing.

  9. Ultrasound evaluation of arthroscopic full-thickness supraspinatus rotator cuff repair: single-row versus double-row suture bridge (transosseous equivalent) fixation. Results of a prospective, randomized study.

    PubMed

    Gartsman, Gary M; Drake, Gregory; Edwards, T Bradley; Elkousy, Hussein A; Hammerman, Steven M; O'Connor, Daniel P; Press, Cyrus M

    2013-11-01

    The purpose of this study was to compare the structural outcomes of a single-row rotator cuff repair and double-row suture bridge fixation after arthroscopic repair of a full-thickness supraspinatus rotator cuff tear. We evaluated with diagnostic ultrasound a consecutive series of ninety shoulders in ninety patients with full-thickness supraspinatus tears at an average of 10 months (range, 6-12) after operation. A single surgeon at a single hospital performed the repairs. Inclusion criteria were full-thickness supraspinatus tears less than 25 mm in their anterior to posterior dimension. Exclusion criteria were prior operations on the shoulder, partial thickness tears, subscapularis tears, infraspinatus tears, combined supraspinatus and infraspinatus repairs and irreparable supraspinatus tears. Forty-three shoulders were repaired with single-row technique and 47 shoulders with double-row suture bridge technique. Postoperative rehabilitation was identical for both groups. Ultrasound criteria for healed repair included visualization of a tendon with normal thickness and length, and a negative compression test. Eighty-three patients were available for ultrasound examination (40 single-row and 43 suture-bridge). Thirty of 40 patients (75%) with single-row repair demonstrated a healed rotator cuff repair compared to 40/43 (93%) patients with suture-bridge repair (P = .024). Arthroscopic double-row suture bridge repair (transosseous equivalent) of an isolated supraspinatus rotator cuff tear resulted in a significantly higher tendon healing rate (as determined by ultrasound examination) when compared to arthroscopic single-row repair. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  10. Busy test week

    NASA Image and Video Library

    2012-11-08

    Jason Hopper of NASA (front row), Jody Ladner of Lockheed Martin (back row, left) and Chris Mulkey of NASA prepare to test the Blue Origin BE-3 engine thrust chamber in the E-1 Test Stand Control Center at John C. Stennis Space Center on Nov. 8. The test was one of 27 conducted in Stennis' E Test Complex the week of Nov. 5.

  11. Bicycle ergometer instrumentation to determine muscle and bone forces during exercise

    NASA Technical Reports Server (NTRS)

    Figueroa, Fernando

    1995-01-01

    It is hypothesized that bone loss experienced by astronauts in zero gravity conditions may be curtailed by appropriate exercise. According to Wolf's law, bone regenerates when muscles produce stresses by pulling on the bone during daily activity and/or exercise on Earth. to use this theory to prevent or decrease bone loss, one needs to quantify musculoskeletal loads and relate them to bone density changes. In the context of the space program, it is desirable to determine musculoskeletal loads during exercise (using the bicycle ergometer in this case) so that one may make similar measurements on Earth and in space. In this manner, load measurements on Earth may be used as reference to generate similar loads during exercise in space. The work reported in this document entails a musculoskeletal load measurement system that, when complete, will provide forces at muscle insertion points and other contact points, on bone. This data will be used by Dr. Beth A. Todd, who is also a SSF working with Dr. Shackelford, as input to a finite element model of bone sections to determine stress distributions. A bicycle ergometer has been instrumented to measure parameters needed to determine musculoskeletal forces during exercise. A primary feature of the system is its compactness. It uses small/light sensors without line-of-sight requirements. The system developed includes sensors, signal processing, a data acquisition system, and software to collect the data. The sensors used include optical encoders to measure position and orientation of the pedal (foot), accelerometers to determine kinematic parameters of the shank and thigh, load cells to measure pedal forces on the sagittal plane, and EMG probes to measure muscle activity. The signals are processed using anti-aliasing filters and amplifiers. The sensors' output is digitized using 30 channels of a board mounted inside a 486 class PC. A program sets the data acquisition parameters and collects data during a time period specified

  12. System manual for the University of Pennsylvania retrofitted solar heated Philadelphia row home (SolaRow)

    SciTech Connect

    Zinnes, I.; Lior, N.

    1980-05-01

    The University of Pennsylvania SolaRow house, an urban row home retrofitted for comfort and domestic hot water heating, was extensively instrumented for performance monitoring and acquisition of weather and solar radiation data. This report describes the heating and instrumentation systems, provides the details for instrumentation, piping and valve identification, and specifies the operation and maintenance of the heating and data acquisition systems. The following are included: (1) system flow diagrams; (2) valve and cable identification tables; (3) wiring diagrams; and (4) start-up, normal operation, shut-down, maintenance and trouble-shooting procedures. It thus provides the necessary technical information to permit system operation and monitoring, overall system performance analysis and optimization, and acquisition of climatological data.

  13. Improving Spectral Results Using Row-by-Row Fourier Transform of Spatial Heterodyne Raman Spectrometer Interferogram.

    PubMed

    Barnett, Patrick D; Strange, K Alicia; Angel, S Michael

    2016-12-12

    This work describes a method of applying the Fourier transform to the two-dimensional Fizeau fringe patterns generated by the spatial heterodyne Raman spectrometer (SHRS), a dispersive interferometer, to correct the effects of certain types of optical alignment errors. In the SHRS, certain types of optical misalignments result in wavelength-dependent and wavelength-independent rotations of the fringe pattern on the detector. We describe here a simple correction technique that can be used in post-processing, by applying the Fourier transform in a row-by-row manner. This allows the user to be more forgiving of fringe alignment and allows for a reduction in the mechanical complexity of the SHRS.

  14. Effect of corn or soybean row position on soil water

    USDA-ARS?s Scientific Manuscript database

    Crop plants can funnel water to the soil and increase water content more in the row relative to the interrow. Because the row intercepts more soil water after rains and higher root density, the soil may also dry out more between rains than does soil in the interrow. The purpose of this study was to ...

  15. 19. VIEW OF THE TWO ROWS OF COKE OVENS, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. VIEW OF THE TWO ROWS OF COKE OVENS, LOOKING EAST. THE OVENS LIE TO THE EAST OF THE MINE BUILDINGS. BEEHIVE OVENS FORM THE ROW ON THE LEFT OF THE PHOTOGRAPH. THE RECTANGULAR OVENS ARE ON THE RIGHT. - Tower Hill No. 2 Mine, Approximately 0.47 mile Southwest of intersection of Stone Church Road & Township Route 561, Hibbs, Fayette County, PA

  16. Multidetector-row CT with a 64-row amorphous silicon flat panel detector

    NASA Astrophysics Data System (ADS)

    Shapiro, Edward G.; Colbeth, Richard E.; Daley, Earl T.; Job, Isaias D.; Mollov, Ivan P.; Mollov, Todor I.; Pavkovich, John M.; Roos, Pieter G.; Star-Lack, Josh M.; Tognina, Carlo A.

    2007-03-01

    A unique 64-row flat panel (FP) detector has been developed for sub-second multidetector-row CT (MDCT). The intent was to explore the image quality achievable with relatively inexpensive amorphous silicon (a-Si) compared to existing diagnostic scanners with discrete crystalline diode detectors. The FP MDCT system is a bench-top design that consists of three FP modules. Each module uses a 30 cm x 3.3 cm a-Si array with 576 x 64 photodiodes. The photodiodes are 0.52 mm x 0.52 mm, which allows for about twice the spatial resolution of most commercial MDCT scanners. The modules are arranged in an overlapping geometry, which is sufficient to provide a full-fan 48 cm diameter scan. Scans were obtained with various detachable scintillators, e.g. ceramic Gd IIO IIS, particle-in-binder Gd IIO IIS:Tb and columnar CsI:Tl. Scan quality was evaluated with a Catphan-500 performance phantom and anthropomorphic phantoms. The FP MDCT scans demonstrate nearly equivalent performance scans to a commercial 16-slice MDCT scanner at comparable 10 - 20 mGy/100mAs doses. Thus far, a high contrast resolution of 15 lp/cm and a low contrast resolution of 5 mm @ 0.3 % have been achieved on 1 second scans. Sub-second scans have been achieved with partial rotations. Since the future direction of MDCT appears to be in acquiring single organ coverage per scan, future efforts are planned for increasing the number of detector rows beyond the current 64- rows.

  17. Development and Evaluation of a Combined Cultivator and Band Sprayer with a Row-Centering RTK-GPS Guidance System

    PubMed Central

    Perez-Ruiz, Manuel; Carballido, Jacob; Agüera, Juan; Rodríguez-Lizana, Antonio

    2013-01-01

    Typically, low-pressure sprayers are used to uniformly apply pre- and post-emergent herbicides to control weeds in crop rows. An innovative machine for weed control in inter-row and intra-row areas, with a unique combination of inter-row cultivation tooling and intra-row band spraying for six rows and an electro-hydraulic side-shift frame controlled by a GPS system, was developed and evaluated. Two weed management strategies were tested in the field trials: broadcast spraying (the conventional method) and band spraying with mechanical weed control using RTK-GPS (the experimental method). This approach enabled the comparison between treatments from the perspective of cost savings and efficacy in weed control for a sugar beet crop. During the 2010–2011 season, the herbicide application rate (112 L ha−1) of the experimental method was approximately 50% of the conventional method, and thus a significant reduction in the operating costs of weed management was achieved. A comparison of the 0.2-trimmed means of weed population post-treatment showed that the treatments achieved similar weed control rates at each weed survey date. Sugar beet yields were similar with both methods (p = 0.92). The use of the experimental equipment is cost-effective on ≥20 ha of crops. These initial results show good potential for reducing herbicide application in the Spanish beet industry. PMID:23478600

  18. Development and evaluation of a combined cultivator and band sprayer with a row-centering RTK-GPS guidance system.

    PubMed

    Perez-Ruiz, Manuel; Carballido, Jacob; Agüera, Juan; Rodríguez-Lizana, Antonio

    2013-03-11

    Typically, low-pressure sprayers are used to uniformly apply pre- and post-emergent herbicides to control weeds in crop rows. An innovative machine for weed control in inter-row and intra-row areas, with a unique combination of inter-row cultivation tooling and intra-row band spraying for six rows and an electro-hydraulic side-shift frame controlled by a GPS system, was developed and evaluated. Two weed management strategies were tested in the field trials: broadcast spraying (the conventional method) and band spraying with mechanical weed control using RTK-GPS (the experimental method). This approach enabled the comparison between treatments from the perspective of cost savings and efficacy in weed control for a sugar beet crop. During the 2010-2011 season, the herbicide application rate (112 L ha(-1)) of the experimental method was approximately 50% of the conventional method, and thus a significant reduction in the operating costs of weed management was achieved. A comparison of the 0.2-trimmed means of weed population post-treatment showed that the treatments achieved similar weed control rates at each weed survey date. Sugar beet yields were similar with both methods (p = 0.92). The use of the experimental equipment is cost-effective on ≥20 ha of crops. These initial results show good potential for reducing herbicide application in the Spanish beet industry.

  19. Prolonged incremental tests do not necessarily compromise VO2max in well-trained athletes.

    PubMed

    Pierce, S J; Hahn, A G; Davie, A; Lawton, E W

    1999-12-01

    Existing literature suggests that tests for maximal oxygen uptake (VO2max) should last 8-12 minutes and that prolonged tests do not produce valid measurements. The research underlying this suggestion has been performed with non-athletic populations and trained athletes may be more tolerant of longer protocols. Eleven rowers (8 males, 3 females) each underwent four different incremental tests on a standard rowing ergometer in randomised counterbalanced order. One of the tests was continuous with workload increments each minute (IT1MIN). This test lasted an average of 12 min+/-4 s (SEM). The other three tests were discontinuous and consisted of 7 stages separated by 1-minute recovery intervals. Stage durations of 3, 4 and 5 min were used in the different tests (IT3MIN, IT4MIN and IT5MIN). Mean values for VO2max were almost identical for IT1MIN (4.56+/-0.22 L x min(-1)), IT3MIN (4.60+/-0.23 L x min(-1)) and IT4MIN (4.60+/-0.21 L x min(-1)), while IT5MIN produced a significantly lower value (4.47+/-0.21 L x min(-1), p<0.05). There was no significant difference between protocols in peak post-exercise blood lactate concentration (approx 13 mmol x L(-1) in each case), but IT1MIN produced lower peak heart rates and higher respiratory exchange ratios. We conclude that with well trained rowing athletes discontinuous test protocols involving 7 stages of 3-4 minutes duration can provide valid measurements of VO2max.

  20. High-Throughput Phenotyping of Wheat and Barley Plants Grown in Single or Few Rows in Small Plots Using Active and Passive Spectral Proximal Sensing

    PubMed Central

    Barmeier, Gero; Schmidhalter, Urs

    2016-01-01

    In the early stages of plant breeding, breeders evaluate a large number of varieties. Due to limited availability of seeds and space, plot sizes may range from one to four rows. Spectral proximal sensors can be used in place of labour-intensive methods to estimate specific plant traits. The aim of this study was to test the performance of active and passive sensing to assess single and multiple rows in a breeding nursery. A field trial with single cultivars of winter barley and winter wheat with four plot designs (single-row, wide double-row, three rows, and four rows) was conducted. A GreenSeeker RT100 and a passive bi-directional spectrometer were used to assess biomass fresh and dry weight, as well as aboveground nitrogen content and uptake. Generally, spectral passive sensing and active sensing performed comparably in both crops. Spectral passive sensing was enhanced by the availability of optimized ratio vegetation indices, as well as by an optimized field of view and by reduced distance dependence. Further improvements of both sensors in detecting the performance of plants in single rows can likely be obtained by optimization of sensor positioning or orientation. The results suggest that even in early selection cycles, enhanced high-throughput phenotyping might be able to assess plant performance within plots comprising single or multiple rows. This method has significant potential for advanced breeding. PMID:27827958

  1. Assertion and validation of the performance of the B3LYP(sup [small star, filled]) functional for the first transition metal row and the G2 test set

    NASA Astrophysics Data System (ADS)

    Salomon, Oliver; Reiher, Markus; Hess, Bernd Artur

    2002-09-01

    The exact exchange part in hybrid density functionals is analyzed with respect to the prediction of ground state multiplicities. It has been found [M. Reiher, O. Salomon, and B. A. Hess, Theor. Chem. Acc., 107, 48 (2001)] that pure and hybrid density functionals yield energy splittings between high-spin and low-spin states of Fe-sulfur complexes that differ by more than 100 kJ/mol and thus fail to reliably predict the correct multiplicity of the ground state. This deviation can lead to meaningless reaction energetics for metal-catalyzed reactions. The finding that the energy splitting depends linearly on the exact exchange admixture parameter led to a new parametrization of the B3LYP functional which was dubbed B3LYP(sup [small star, filled]). In the present paper we investigate the generality and transferability of this functional. We study the extent to which the exact exchange admixture affects the thermochemistry validated with respect to the reference data set of molecules from the G2 test set. Metallocenes and bis(benzene) metal complexes of the first transition metal period are chosen to test the transferability of the findings for Fe-sulfur complexes. Moreover, the slope of the linear dependence of the energy splitting of high-spin and low-spin states on the amount of admixture of exact exchange is studied in detail.

  2. Shoulder muscle recruitment patterns during a kayak stroke performed on a paddling ergometer.

    PubMed

    Trevithick, Beverley A; Ginn, Karen A; Halaki, Mark; Balnave, Ronald

    2007-02-01

    Precise muscle co-ordination is required to maintain normal shoulder function and alterations in synchrony between shoulder muscles can result in loss of full range of movement and pain. Although shoulder pain in kayakers is high with 53% of elite international paddlers reporting shoulder injuries, little information is available regarding the pattern of shoulder muscle recruitment during paddling. The aim of this study was to investigate the normal recruitment pattern of shoulder muscles during the kayak stroke. Nine recreational paddlers without shoulder pain were examined. EMG data from eight shoulder muscles of the dominant arm were collected simultaneously with video data during simulated paddling on an ergometer. EMG data was normalized to time and peak amplitude. Intersubject consistency was evaluated using Pearson correlation analysis. The results of this study indicated a fair to high correlation in at least one phase of the kayak stroke in five of the muscles examined: upper trapezius, supraspinatus, latissimus dorsi, serratus anterior and rhomboid major. This normative data will enable comparisons with the shoulder muscle recruitment patterns in kayakers with shoulder pain in order to determine the role of altered motor control in the painful kayaking shoulder.

  3. STS-40 Mission Specialist (MS) Seddon on ergometer conducts Exp. No. 066

    NASA Image and Video Library

    1991-06-14

    STS040-211-019 (5-14 June 1991) --- Astride the bicycle ergometer, astronaut Rhea Seddon, mission specialist, breathes into the cardiovascular re-breathing unit during the exercise phase of an experiment. The investigation, In-flight Study of Cardiovascular Deconditioning (Experiment 066), was developed by Dr. Leon E. Farhi of the State University of New York in Buffalo. It focuses on the deconditioning of the heart and lungs and changes in cardiopulmonary function that occur upon return to Earth. By using non-invasive techniques of prolonged expiration and re-breathing, investigators can determine the amount of blood pumped out of the heart (cardiac output), the ease with which blood flows through all the vessels (total peripheral resistance), oxygen used and carbon dioxide released by the body, and lung function and volume changes. Measurements are made both while crew members are resting and while they pedal the exercise bicycle, as Dr. Seddon is doing here. This scene was photographed with a 35mm camera.

  4. Metabolic responses to submaximal treadmill walking and cycle ergometer pedalling in obese adolescents.

    PubMed

    Lafortuna, C L; Lazzer, S; Agosti, F; Busti, C; Galli, R; Mazzilli, G; Sartorio, A

    2010-08-01

    Physical activity is essential in obesity management because of the impact of exercise-related energy expenditure (EE) and fat oxidation (Fox) rate on a daily balance, but the specific physiological effects of different exercise modalities are scarcely known in obese individuals. The objective of the study was to compare the metabolic responses to treadmill (TM) and cycle ergometer (CE) exercise in obese adolescents. Gas exchange, heart rate (HR), blood lactate (LA) concentration, EE and Fox were determined at different intensity levels (up to about 85% of maximal oxygen uptake) during TM and CE in 14 pubertal (Tanner stage: >3) obese (BMI SDS: 2.15-3.86) male adolescents (age: 13-18 years). At comparable HR, oxygen uptake, EE and Fox were higher, and LA lower, during TM than CE (P<0.05-0.001), suggesting that cycling imposes a metabolic involvement at the level of the single active muscles greater than walking. Therefore, due to different physiological responses to TM and CE, walking was more convenient than cycling in obese adolescents, permitting to attain the same EE at lower HR, with lower blood LA concentration and with greater Fox. These conclusions seem clinically relevant when using exercise as a part of multidisciplinary treatment for juvenile obesity and amelioration of related metabolic disturbances.

  5. The energetic and cardiovascular response to treadmill walking and cycle ergometer exercise in obese women.

    PubMed

    Lafortuna, Claudio L; Agosti, Fiorenza; Galli, Raffaela; Busti, Carlo; Lazzer, Stefano; Sartorio, Alessandro

    2008-08-01

    Physical activity is essential in obesity management, but exercise capacity is compromised in obese individuals due to the excessive body mass, impacting on body movement's energetics, and to the dysfunctions of regulatory mechanisms, affecting cardiovascular responses. This study aims to compare the energetics and cardiovascular responses of walking and cycling in obese women, and to formulate recommendations regarding the most suitable type of exercise for obesity. Fifteen obese (OB) and six normal weight (NW) women exercised on treadmill (TM) and cycle ergometer (CE). During both exercise modalities, metabolic rate was higher in OB than in NW and correlated with measures of body mass. Leg movement metabolic rate during cycling depended upon individual adiposity, and when accounted for, mechanical efficiency was similar in the two groups. When accounting for extra mass, differences in metabolic rate among groups are abolished for CE, indicating no obesity impairment of muscle efficiency, but not for TM, suggesting that differences in biomechanics may explain the higher net cost of transport of OB. In both groups, HR was higher during CE than TM at the same oxygen uptake (VO(2)), but in OB the HR increment over VO(2) was greater for CE than for TM. Therefore, due to different cardiovascular responses to TM and CE in OB, walking is more convenient, enabling OB to attain target energy expenditure at lower HR or in a shorter time.

  6. Net caloric cost of a 3-set flywheel ergometer resistance exercise paradigm.

    PubMed

    Caruso, John F; Hernandez, Dan A

    2002-11-01

    Subjects (n = 23) performed three 3 x 8 seated leg press workouts on a flywheel ergometer to note the net caloric cost. This study's purpose was to examine net caloric cost as a function of total work on an inertial resistance exercise device offering more eccentric loading than conventional isotonic weight training equipment. High intraclass correlations for net caloric cost (0.89) and total work (0.94) result from data collected from 3 workouts. Average total work and net caloric cost values reveal a significant (r = 0.62, p < 0.05) correlation yielding the following equation: predicted net caloric cost = 33.2 + 0.006014331 (total work). Current study data also show favorable net caloric cost (1.24 kcal x kg(-1) x d(-1)), exercise efficiency (9.48 kcal x 10(-3) per joule), and estimated mechanical loading (65 W min x kg(-1) LBM x d(-1)) values. The results of the current study serve as baseline knowledge for exercise prescriptions pertaining to net caloric cost, exercise efficiency, and mechanical loading using this device.

  7. Concentrated animal feeding operations, row crops, and their relationship to nitrate in eastern Iowa Rivers.

    PubMed

    Weldon, Mark B; Hornbuckle, Keri C

    2006-05-15

    Concentrated animal feeding operations (CAFO) and fertilizer application to row crops may contribute to poor water quality in surface waters. To test this hypothesis, we evaluated nutrient concentrations and fluxes in four Eastern Iowa watersheds sampled between 1996 and 2004. We found that these watersheds contribute nearly 10% of annual nitrate flux entering the Gulf of Mexico, while representing only 1.5% of the contributing drainage basin. Mass budget analysis shows streamflow to be a major loss of nitrogen (18% of total N output), second only to crop harvest (63%). The major watershed inputs of nitrogen include applied fertilizer for corn (54% of total N input) and nitrogen fixation by soybeans (26%). Despite the relatively small input from animal manure (approximately 5%), the results of spatial analysis indicate that row crop and CAFO densities are significantly and independently correlated to higher nitrate concentration in streams. Pearson correlation coefficients of 0.59 and 0.89 were found between nitrate concentration and row crop and CAFO density, respectively. Multiple linear regression analysis produced a correlation for nitrate concentration with an R2 value of 85%. High spatial density of row crops and CAFOs are linked to the highest river nitrate concentrations (up to 15 mg/L normalized over five years).

  8. The impact of fluctuations in boat velocity during the rowing cycle on race time.

    PubMed

    Hill, H; Fahrig, S

    2009-08-01

    In competitive rowing, the fluctuations in boat velocity during the rowing cycle are associated with an increased water resistance of the boat as compared with a boat moving at a constant velocity. We aimed to quantify the influence of the increased water resistance on race time using a mathematical approximation, based on the increase in physiological power being proportional to the 2nd power of boat speed. Biomechanical data (oar force, rowing angle, boat velocity, and boat acceleration) were measured when eight elite coxless pair crews performed a rowing test with a stepwise increasing stroke rate (SR: 20, 24, 28, and 32 min(-1)) that successively increased the mean boat speed. The results revealed a +4.59 s (SR 24.2) to +5.05 s (SR 31.5) 2000-m race-time difference compared with a boat hypothetically moving without velocity fluctuations. Velocity fluctuations were highly correlated with SR (r=0.93) because the accelerations of the rowers' body mass and the mass of the counteracting boat increase with SR. The possibilities to reduce velocity fluctuations and therefore race time are limited. For elite rowers, race time may be slightly reduced by a moderate reduction in SR that is compensated by an increased force output for each stroke.

  9. Starvation Can Result From Inadequate Dietary Planning for a 50-Day Rowing Expedition.

    PubMed

    Reid, Hamish Ab; Dennison, Nicholas C; Quayle, Jonathan; Preston, Tom

    2016-12-14

    Meeting the energy demands of prolonged arduous expeditions and endurance sport may be a significant barrier to success. Expedition rowing is associated with high levels of body mass loss, reflecting the challenge of meeting energy expenditure in this exacting environment. This study used the Doubly Labelled Water (DLW) technique to calculate the Total Energy Expenditure (TEE), and body composition changes of two 28-year-old healthy male athletes during a 50-day continuous and unsupported row around Great Britain. A measured dose of DLW was taken at the start of two separate study periods (days five to 19 and 34 to 48) followed by sequential urine collection, which was analysed on return to land. Mean TEE was 15.3MJ/day: Athlete 1 16.4MJ/day, Athlete 2 14.9MJ/day. Athlete 1 lost 11.2kg and Athlete 2 lost 14.9kg of body mass during the row. Average energy provision was 19.1MJ per 24-hour ration pack. These results highlight the difficulty of maintaining energy balance during expedition rowing. A starvation state was observed despite dietary provision in excess of estimated energy expenditure, indicating nutritional strategy rather than caloric availability was at fault. We recommend future expeditions prioritise thorough testing and the individualisation of rations to ensure they are both palatable and practical during the weeks to months at sea.

  10. Concentrated Animal Feeding Operations, Row Crops and their Relationship to Nitrate in Eastern Iowa Rivers

    PubMed Central

    Weldon, Mark B.; Hornbuckle, Keri C.

    2009-01-01

    Concentrated animal feeding operations (CAFO) and fertilizer application to row crops may contribute to poor water quality in surface waters. To test this hypothesis, we evaluated nutrient concentrations and fluxes in four Eastern Iowa watersheds sampled between 1996-2004. We found that these watersheds contribute nearly 10% of annual nitrate flux entering the Gulf of Mexico, while representing only 1.5% of the contributing drainage basin. Mass budget analysis shows stream flow to be a major loss of nitrogen (18% of total N output), second only to crop harvest (63%). The major watershed inputs of nitrogen include applied fertilizer for corn (54% of total N input) and nitrogen fixation by soybeans (26%). Despite the relatively small input from animal manure (~5%), the results of spatial analysis indicate that row crop and CAFO densities are significantly and independently correlated to higher nitrate concentration in streams. Pearson correlation coefficients of 0.59 and 0.89 were found between nitrate concentration and row crop and CAFO density, respectively. Multiple linear regression analysis produced a correlation for nitrate concentration with an R2 value of 85%. High spatial density of row crops and CAFOs are linked to the highest river nitrate concentrations (up to 15 mg/l normalized over five years). PMID:16749677

  11. CFD Simulations of Supersonic Highly Swirling Flow Exiting a Turbine Vane Row Compared with Experimental Observations

    NASA Technical Reports Server (NTRS)

    West, Jeff S.; Richardson, Brian R.; Schmauch, Preston; Kenny, Robert J.

    2011-01-01

    Marshall Space Flight Center (MSFC) has been heavily involved in developing the J2-X engine. The Center has been testing a Work Horse Gas Generator (WHGG) to supply gas products to J2-X turbine components at realistic flight-like operating conditions. Three-dimensional time accurate CFD simulations and analytical fluid analysis have been performed to support WHGG tests at MSFC. The general purpose CFD program LOCI/Chem was utilized to simulate flow of products from the WHGG through a turbine manifold, a stationary row of turbine vanes, into a Can and orifice assembly used to control the back pressure at the turbine vane row and finally through an aspirator plate and flame bucket. Simulations showed that supersonic swirling flow downstream of the turbine imparted a much higher pressure on the Can wall than expected for a non-swirling flow. This result was verified by developing an analytical model that predicts wall pressure due to swirling flow. The CFD simulations predicted that the higher downstream pressure would cause the pressure drop across the nozzle row to be approximately half the value of the test objective. With CFD support, a redesign of the Can orifice and aspirator plate was performed. WHGG experimental results and observations compared well with pre-test and post-test CFD simulations. CFD simulations for both quasi-static and transient test conditions correctly predicted the pressure environment downstream of the turbine row and the behavior of the gas generator product plume as it exited the WHGG test article, impacted the flame bucket and interacted with the external environment.

  12. Ergometer-cycling with strict versus minimal contact supervision among the oldest adults: A cluster-randomised controlled trial.

    PubMed

    Van Roie, Evelien; Martien, Sofie; Hurkmans, Emalie; Pelssers, Johan; Seghers, Jan; Boen, Filip; Delecluse, Christophe

    To evaluate the feasibility and short- and long-term effects of two 10-wk structured ergometer-cycling programs among elderly in assisted-living residences. Eight assisted-living residences (N=95; age=81.2±5.9years) were randomly assigned to one of three conditions: 1) ergometer-cycling with strict coach-supervision (STRICT, N=3; n=35); 2) ergometer-cycling with autonomy-supportive minimal contact coach-supervision (AUT; N=3; n=36); or 3) control condition (CON; N=2, n=24). Three-weekly progressive ergometer-cycling sessions for 10 weeks. Feasibility, physical activity (PA), muscular strength, functional performance and quality of life (baseline, post-intervention (10weeks) and 6-month follow-up). 83 participants were analyzed post-intervention, 75 at follow-up. Adherence was higher in STRICT than AUT during the intervention (p=0.001), but not during follow-up. Compared with CON, both programs showed positive short- and long-term effects on moderate-intensity PA (p=0.034). With regard to strength, functional performance and well-being, no time-by-group interaction effects were found. When comparing high-adherers (adherence≥80%) to low-adherers, a greater increase in functional performance and in well-being and a trend towards a lower decrease in strength were found in the short-term (p=0.047, p<0.001 and p=0.054, respectively). Both interventions were feasible and equally effective to increase long-term engagement in PA, irrespective of the type of supervision. When adherence is high, positive effects on strength, performance and well-being can be expected. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Proximal Row Carpectomy Combined with Wrist Hemiarthroplasty

    PubMed Central

    Culp, Randall W.; Bachoura, Abdo; Gelman, Scott E.; Jacoby, Sidney M.

    2012-01-01

    Proximal row carpectomy (PRC) combined with distal radius hemiarthroplasty is a relatively novel procedure that rivals total wrist arthrodesis and offers a new surgical treatment option for select patients with painful, end-stage wrist disease. We present our early experience with this procedure. A retrospective chart review was conducted for nonrheumatoid patients diagnosed with wrist arthritis and subsequently treated with wrist hemiarthroplasty combined with PRC. The minimum follow-up duration was 12 months. Preoperative and postoperative flexion, extension, and grip strength were recorded. Postoperative radiographic findings were assessed. The Patient-Rated Wrist Evaluation (PRWE) questionnaire was administered to gauge postoperative pain and function. The records of 10 patients were reviewed. The mean age was 64 years and the mean postoperative follow-up duration was 19 months. Postoperative flexion, extension, and grip strength were all found to be less than the preoperative levels. The mean postoperative PRWE score for pain and function were 26 and 23, respectively. The complications were diverse and occurred at a relatively high rate. PRC combined with distal radius hemiarthroplasty is a novel procedure that offers a potential surgical option for the treatment of wrist arthritis in select patients. Our early experience has lead us to modify our technique with regard to the implant material, and at this stage, the surgical technique and the most appropriate implant may require further optimization. The level of evidence for this study is IV (therapeutic). PMID:23904978

  14. Distal radius fracture after proximal row carpectomy

    PubMed Central

    Igeta, Yuka; Naito, Kiyohito; Sugiyama, Yoichi; Obata, Hiroyuki; Aritomi, Kentaro; Kaneko, Kazuo; Obayashi, Osamu

    2015-01-01

    Introduction We encountered a patient with distal radius fracture (DRF) after proximal row carpectomy (PRC). The mechanism of the DRF after PRC is discussed in this report. Presentation of case The patient was a 73-year-old female who had undergone PRC due to Kienböck disease before. The wrist range of motion was: 45° on dorsiflexion and 20° on flexion. DRF has occurred at 3 years after PRC. The fracture type was extra-articular fracture. Osteosynthesis was performed using a volar locking plate. No postoperative complication developed, the Mayo score was excellent at 6 months after surgery, and the daily living activity level recovered to that before injury. Discussion Since the wrist range of motion decreased and the lunate fitted into the joint surface after PRC, making the forearm join with the hand like a single structure, pressure may have been loaded on the weak distal end of the radius from the dorsal side, causing volar displacement and fracture. Conclusion The pressure distribution and range of motion of the radiocarpal joint after PRC are different from those of a normal joint, and the mechanism of fracture also changes due to PRC. PMID:25623755

  15. Hydrodynamic performance of multiple-row slotted breakwaters

    NASA Astrophysics Data System (ADS)

    Elbisy, Moussa S.; Mlybari, Ehab M.; Helal, Medhat M.

    2016-06-01

    This study examines the hydrodynamic performance of multiple-row vertical slotted breakwaters. We developed a mathematical model based on an eigenfunction expansion method and a least squares technique for Stokes second-order waves. The numerical results obtained for limiting cases of double-row and triple-row walls are in good agreement with results of previous studies and experimental results. Comparisons with experimental measurements of the reflection, transmission, and dissipation coefficients ( C R , C T , and C E ) for double-row walls show that the proposed mathematical model adequately reproduces most of the important features. We found that for double-row walls, the C R increases with increasing wave number, kd, and with a decreasing permeable wall part, dm. The C T follows the opposite trend. The C E slowly increases with an increasing kd for lower kd values, reaches a maximum, and then decreases again. In addition, an increasing porosity of dm would significantly decrease the C R , while increasing the C T . At lower values of kd, a decreasing porosity increases the C E , but for high values of kd, a decreasing porosity reduces the C E . The numerical results indicate that, for triple-row walls, the effect of the arrangement of the chamber widths on hydrodynamic characteristics is not significant, except when kd<0.5. Double-row slotted breakwaters may exhibit a good wave-absorbing performance at kd>0.5, where by the horizontal wave force may be smaller than that of a single wall. On the other hand, the difference between double-row and triple-row vertical slotted breakwaters is marginal.

  16. Maximal strength on different resistance training rowing exercises predicts start phase performance in elite kayakers.

    PubMed

    Ualí, Ismael; Herrero, Azael J; Garatachea, Nuria; Marín, Pedro J; Alvear-Ordenes, Ildefonso; García-López, David

    2012-04-01

    This study aimed to examine the relationship existing between maximum strength values in 2 common resistance training row exercises (bilateral bench pull [BBP] and one-arm cable row [OACR]) and short sprint performance in elite kayakers. Ten junior kayakers (5 women and 5 men) were tested on different days for 1 repetition maximum (1RM) and maximal voluntary isometric contraction in both exercises. Moreover, a 12-m sprint kayak was performed in a dew pond to record split times (2, 5, and 10 m), peak velocity, distance completed considering the first 8 strokes, and mean acceleration induced by right blade and left blade strokes. No differences (p > 0.05) were observed when right and left arms were compared in sprint testing or strength testing variables. Maximal strength values in BBP and OACR were significantly correlated with short sprint performance variables, showing the bilateral exercise with slightly stronger correlation coefficients than the unilateral seated row. Moreover, the relationship between strength testing and sprint testing variables is stronger when maximal force is measured through a dynamic approach (1RM) in comparison with an isometric approach. In conclusion, maximal strength in BBP and OACR is a good predictor of the start phase performance in elite sprint kayakers, mainly the 1RM value in BBP.

  17. Intravenous bicarbonate and sodium chloride both prolong endurance during intense cycle ergometer exercise.

    PubMed

    Mitchell, T H; Abraham, G; Wing, S; Magder, S A; Cosio, M G; Deschamps, A; Marliss, E B

    1990-08-01

    To determine the effects of neutralizing exercise systemic acidosis via the intravenous route upon endurance and metabolic responses, eight lean, normal, postabsorptive men exercised to exhaustion at about 80% of their VO2 max (69 +/- 3%, mean +/- SEM, of maximum power output) on a cycle ergometer. Exercise studies were performed either with no infusion (control) or with a total infusion volume of about 1.5 L, mainly as 1.3% sodium bicarbonate or as 0.9% sodium chloride (NaCl), infused (double-blind) throughout exercise. The sodium bicarbonate was to prevent acid-base change, the sodium chloride was as a control for the volume infused. Arterialized venous blood and breath-by-breath analysis of expired gases were obtained. [H+] (nmol.L-1) and [HCO3-] (mmol.L-1) at exhaustion were similar in control and NaCl (46.5 +/- 1.8, 19.9 +/- 0.9), but remained unchanged from rest values with bicarbonate (38.4 +/- 0.9, 24.8 +/- 1.5, p less than 0.005 vs control and NaCl). At exhaustion, VO2, VCO2, RER, heart rate, and systolic BP as well as FFA, glycerol, alanine, insulin, norepinephrine, and epinephrine did not differ among protocols. Endurance was markedly prolonged (p less than 0.01) with bicarbonate (31.9 +/- 5.8 min) and NaCl (31.8 +/- 4.1 min) compared with the control (19.0 +/- 2.9 min) condition. Plasma glucose at exhaustion was higher (p less than 0.025) in the control compared to bicarbonate and NaCl experiments, while lactate was higher (p less than 0.025) in the bicarbonate than in the control and NaCl experiments. Thus, the prolonged endurance with sodium bicarbonate infusion could not be explained either by its effect of maintaining blood acid-base equilibrium or concomitant metabolic changes.

  18. Loading of the knee joint during ergometer cycling: telemetric in vivo data.

    PubMed

    Kutzner, Ines; Heinlein, Bernd; Graichen, Friedmar; Rohlmann, Antonius; Halder, Andreas M; Beier, Alexander; Bergmann, Georg

    2012-12-01

    Within-subject, repeated-measures design. To measure tibiofemoral contact forces during cycling in vivo and to quantify the influences of power, pedaling cadence, and seat height on tibiofemoral contact forces. Cycling is usually classified as a low-demand activity for the knee joint and is therefore recommended for persons with osteoarthritis and rehabilitation programs following knee surgery. However, there are limited data regarding actual joint loading. Instrumented knee implants with telemetric data transmission were used to measure the tibiofemoral contact forces. Data were obtained in 9 subjects, during ergometer cycling and walking, 15 ± 7 months after total knee arthroplasty. Tibiofemoral forces during cycling at power levels between 25 and 120 W, cadences of 40 and 60 rpm, and 2 seat heights were investigated. Within the examined power range, tibiofemoral forces during cycling were smaller than those during walking. At the moderate condition of 60 W and 40 rpm, peak resultant forces of 119% of body weight were measured during the pedal downstroke. Shear forces ranged from 5% to 7% of body weight. Forces increased linearly with cycling power. Higher cadences led to smaller forces. A lower seat height did not increase the resultant force but caused higher posterior shear forces. Due to the relatively small tibiofemoral forces, cycling with moderate power levels is suited for individuals with osteoarthritis and rehabilitation programs following knee surgery, such as cartilage repair or total knee replacement. The lowest forces can be expected while cycling at a low power level, a high cadence, and a high seat height.

  19. Drink composition and cycle-ergometer endurance in men: Carbohydrate, Na(+), osmolality

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Looft-Wilson, R.; Wisherd, J. L.; Marchman, N.; Wells, T.; Barnes, P. R.; Wong, L. G.

    1994-01-01

    Cycle-ergometer endurance performance was determined in 5 untrained men (22-39 yr, 62.4-100.5 kg, 29-55 mL x min(exp -1) x kg(exp -1) peak oxygen uptake) after consuming Nothing (N) or two fluid formulations (10 mL x kg(exp -1), 555-998 mL). Performance 1 (P1), a multi-ionic-glucose rehydration drink, contains 55 mEq/L Na(exp +), 416 mg/dL citrate, 2,049 mg/dL glucose, and 365 mOsm/kgH2O. HyperAde (HA), a sodium chloride-citrate hyperhydration drink, contains 164 mEq/L Na(exp +), 854 mg/dL citrate, less than 0.5 mg/dL glucose, and 253 mOsm/kgH2O. Endurance at a load of 87-91 percent of peak VO2 was 30.50 +/- SE 3.44 min with HA; 24.55 +/- 1.09 min with P1 (p greater than 0.10 from HA); and 24.68 +/- 1.50 min with N (p less than 0.05 from HA). The attenuated endurance performance with P1 and N could not be attributed to differences in exercise metabolism, change or absolute level of rectal and mean skin temperature, or change in perceived exertion. The greater increase in resting plasma volume with HA, compared with P1 or N, probably contributed to the greater endurance with HA.

  20. Growth hormone levels after flywheel ergometer exercise: correlation with independent variables.

    PubMed

    Caruso, John F; Coday, Michael A; Monda, Julie K; Ramey, Elizabeth S; Hastings, Lori P; Marshall, Mallory R

    2009-07-01

    In-flight muscle mass and strength losses are likely exacerbated by low growth hormone (GH) concentrations. Factors associated with exercise may foretell resultant GH levels and thereby help blunt future mass and strength losses. To assess the ability of variables to predict GH variance from resistive exercise done on a flywheel ergometer (FE) designed for in-flight exercise, subjects (N=17) performed three types of workouts on the device. With a randomized design, subjects performed the workouts with the intent to determine if changes in post-exercise GH concentrations are impacted by contractile mode and workload. Body mass, blood lactate (BLa-) concentrations, and peak angular velocity (PAV), average power (AP), and total work (TW) from workouts attempted to predict GH variance. Pre-exercise blood draws, and at 1 and 30 min after workouts, were used to determine GH concentrations. BLa- levels were measured before workouts and at 5 min post-exercise. Delta (8, post-pre) and 30-min post-workout GH levels served as criterion variables. Multivariate regression with an alpha < or = 0.05 yielded the following significant prediction equation: deltaGH = 13.64 - 0.014 (body mass) - 0.607 (post-exercise BLa-) + 0.659 (deltaBLa-) - 0.624(PAV) + 0.653(TW) + 0.147(AP). Univariate correlations show body mass, deltaBLa-, and TW were the best predictors of deltaGH variance. Future research should also attempt to identify additional variables that account for the unexplained GH variance from FE workouts.

  1. The Row-Column Multiplication of High Dimensional Rhotrices

    ERIC Educational Resources Information Center

    Sani, B.

    2007-01-01

    This paper presents the row-column multiplication of rhotrices that are of high dimension. This is an extension of the same multiplication carried out on rhotrices of dimension three, considered to be the base rhotrices.

  2. THERMALWATER FLOW METER. Hot Springs National Park, Bathhouse Row, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    THERMAL-WATER FLOW METER. - Hot Springs National Park, Bathhouse Row, Superior Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  3. 1. View looking southeast down senior officer row. Building 6 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View looking southeast down senior officer row. Building 6 on left and senior officer housing on right. Galaxy Street in foreground. - Chanute Air Force Base, East of Route 45 & south of Rantoul, Rantoul, Champaign County, IL

  4. 26. INTERIOR VIEW SHOWING ROW OF TIMBER SUPPORT TOWERS BUILT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. INTERIOR VIEW SHOWING ROW OF TIMBER SUPPORT TOWERS BUILT AS TEMPORARY TRUSS REINFORCEMENT (NOTE STEEL STRUCTURES ATOP TIMBER BRACING) - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  5. Detail, starpattern balustrade of north span, from northwest, showing row ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail, star-pattern balustrade of north span, from northwest, showing row of four star-pattern railing slabs bracketed by simple molded concrete balusters - Horner Street Bridge, Horner Street over Stonycreek River, Johnstown, Cambria County, PA

  6. General view of building in context showing row of residences ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    General view of building in context showing row of residences adjacent to golf course, facing northeast. - Marine Barracks, Panama Canal, Officers' Quarters, 800' West of Bruja Road, Balboa, Former Panama Canal Zone, CZ

  7. INTERIOR SECOND FLOOR EAST END LOOKING WEST AT NORTH ROW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR SECOND FLOOR- EAST END LOOKING WEST AT NORTH ROW OF MUSHROOM COLUMNS. - Colt Fire Arms Company, South Armory Building, 36-150 Huyshope Avenue, 17-170 Van Dyke Avenue, 49 Vredendale Avenue, Hartford, Hartford County, CT

  8. Detail view of stylized panel on end of seating row ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view of stylized panel on end of seating row - National Home for Disabled Volunteer Soldiers, Pacific Branch, Wadsworth Theater, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  9. Rows of barrack, Building No. 909 (left) and Building No. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Rows of barrack, Building No. 909 (left) and Building No. 910 (right), looking 82 degrees east - Presidio of San Francisco, Enlisted Men's Barracks Type, West end of Crissy Field, between Pearce & Maudlin Streets, San Francisco, San Francisco County, CA

  10. Row of barracks, Building No. 902 (right) and Building No. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Row of barracks, Building No. 902 (right) and Building No. 903 (left), looking 277 degrees west - Presidio of San Francisco, Enlisted Men's Barracks Type, West end of Crissy Field, between Pearce & Maudlin Streets, San Francisco, San Francisco County, CA

  11. INTERIOR, SOUTH PART, CAMERA FACING SOUTHWEST. DOUBLE ROW OF CENTER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR, SOUTH PART, CAMERA FACING SOUTHWEST. DOUBLE ROW OF CENTER COLUMNS REFLECTS SOUTH PART'S RE-USE OF ANOTHER BUILDING'S STRUCTURAL FRAME. - New Haven Rail Yard, Work Equipment Shop, Vicinity of Cedar & Lamberton Streets, New Haven, New Haven County, CT

  12. 7. Row of pumps against first floor interior west wall. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Row of pumps against first floor interior west wall. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Oil House, 650 feet Southeast of Cliff & Mechanic Streets, Scranton, Lackawanna County, PA

  13. 4. VIEW NORTHWEST, INTERIOR OF GATEHOUSE, SHOWING ROW OF GATE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VIEW NORTHWEST, INTERIOR OF GATEHOUSE, SHOWING ROW OF GATE OPERATING MECHANISMS; HEIGHT OF STEMS INDICATES FOREGROUND GATE IS OPEN - Norwich Water Power Company, Headgates, West bank of Shetucket River opposite Fourteenth Street, Greenville section, Norwich, New London County, CT

  14. Cell block eleven, looking from the "Death Row" exercise yard, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Cell block eleven, looking from the "Death Row" exercise yard, facing north (note cell block fifteen to the right and cell block fourteen in the distance_ - Eastern State Penitentiary, 2125 Fairmount Avenue, Philadelphia, Philadelphia County, PA

  15. Harvester Productivity for Row Thinning Loblolly Pine Plantations

    Treesearch

    James E. Granskog; Walter C. Anderson

    1980-01-01

    Tivo tree harvesters currently being used to thin southern pine plantations were evaluated to determine the effects of stand characteristics on machine productivity. Production rates for row thinning loblolly plantations are presented by stand age, site index, and stand density.

  16. Ten-year effects from row thinnings in loblolly pine plantations of eastern Maryland

    Treesearch

    Silas Little; John J. Mohr; Paul V. Mook

    1967-01-01

    Four degrees of row thinning were tested in 17-year-old loblolly pine plantations of eastern Maryland. In the following 10 years diameter and basal-area growth of tagged trees increased in relation to intensity of thinning. The heavier thinnings also had the most effect in increasing live-crown lengths and ratios and in favoring crown-class position. Volume growth was...

  17. Age and sex differences in paranormal beliefs: a response to Vitulli, Tipton, and Rowe (1999)

    PubMed

    Irwin, H J

    2000-04-01

    Vitulli, Tipton, and Rowe (1999) report evidence of age and sex differences in the strength of paranormal beliefs. An alternative interpretation of their data is offered in terms of differential item functioning. It is suggested that respondents' interpretation of paranormal belief test items may vary with age and sex, and that such differences in the strength with which such beliefs are endorsed has not been conclusively established by Vitulli, et al.

  18. Double row repair: is it worth the hassle?

    PubMed

    Papalia, Rocco; Franceschi, Francesco; Del Buono, Angelo; Zampogna, Biagio; Maffulli, Nicola; Denaro, Vincenzo

    2011-12-01

    In the operative management of rotator cuff disease, comparable functional results have been reported after open or mini-open repair and arthroscopic fixation. Surgical repair aims to re-establish an anatomical configuration of the tendon-bone construct for restoring its mechanical performance. Single row repair is the most commonly used technique, but recently some authors have proposed to re-establish the rotator cuff footprint with 2 rows of suture anchors ("double row" repair). In regard to imaging assessment, at time zero double row repair results being more anatomic and allows for structurally sound restoration of the rotator cuff footprint. However, this does not seem to translate into superior clinical outcomes for the double row repair when evaluating all different sizes of rotator cuff tears as a whole. The scientific basis for recommending single or double row repair as preferred treatment for patients with rotator cuff tear is questionable, as minimal differences have been measured on clinical and functional rating scales.

  19. Lactic acid removal and heart rate frequencies during recovery after strenuous rowing exercise.

    PubMed Central

    Koutedakis, Y; Sharp, N C

    1985-01-01

    Three tests were conducted to assess the effectiveness of three different intensities of exercise both in reducing blood lactic acid (LA) levels and in influencing subjects' heart rate (HR), following a 2000 m race in a rowing boat. In the first and second tests these variables were investigated during a 13 min recovery exercise at 60% and 40% of the preceding maximum rowing speed respectively. In the third test the subjects had a resting recovery. The results include a significant increase (P less than 0.001) in the rate of lactate removal following the 40% recovery compared with the 60% and resting recoveries. The HRs were significantly lower during the last minute of resting recovery compared with 40% and 60% recoveries (P less than 0.001). The same was true when 40% recovery was compared with 60% recovery (P less than 0.001). The present data suggest firstly that 40% of the maximum rowing speed is an appropriate pace for effective LA removal and secondly that, at least for trained rowers, 86% of their maximum HR can be taken as an indication of work of an intensity at or above anaerobic threshold. Images p199-a p199-b p201-a PMID:4092140

  20. 77 FR 74237 - T. Rowe Price Associates, Inc., et al.; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-13

    ... COMMISSION T. Rowe Price Associates, Inc., et al.; Notice of Application December 7, 2012. AGENCY: Securities... for an exemption from sections 12(d)(1)(A) and (B) of the Act. Applicants: T. Rowe Price Associates, Inc. (``TRP''), T. Rowe Price Institutional Income Funds, Inc. (the ``Corporation'') and T. Rowe Price...

  1. Characterization of the use of a cycle ergometer to assist in the physical therapy treatment of critically ill patients

    PubMed Central

    Pires-Neto, Ruy Camargo; Pereira, Aná Luiza; Parente, Camila; de Sant'Anna, Guadalupe Nery; Esposito, Daniela Daguer; Kimura, Aline; Fu, Carolina; Tanaka, Clarice

    2013-01-01

    Objective The objective of this study was to use a cycle ergometer to assess cardiorespiratory changes during active exercise and to verify patients' satisfaction with this type of activity. Methods A single intervention involving active lower limb exercise was performed with a cycle ergometer (without load) for 5 minutes. The following variables were measured before, during and immediately after exercise: heart rate, blood pressure, respiratory rate, peripheral oxygen saturation and the Borg dyspnea scale score. Following the exercise, the patients answered a questionnaire to evaluate their satisfaction with this type of activity. Results A total of 38 patients (65% male) with a mean age of 48 ± 16 years old participated in the study. Enrolled patients presented a sequential organ failure assessment (SOFA) score of 2 (0 - 5 scale). During the exercise, 16% of the patients used ventilation support and 55% of them were breathing at room air. A comparison of the initial and final values of the variables indicated increases in the heart rate (92±17 beats/min vs. 95±18 beats/min; p<0.05), the respiratory rate (19 ± 8 breaths/min vs. 23±8 breaths/min; p<0.05) and the Borg dyspnea scale score (1.3±1.8 vs. 2.8±2.2; p<0.05). In addition, 85% of the patients reported enjoying the activity. Only 25% of the patients reported some discomfort, and 100% of the patients wanted to repeat this type of activity in future treatments. Conclusion During the cycle ergometer exercises, minor cardiorespiratory changes were observed in the patients. The evaluated patients reported high satisfaction with this type of activity. PMID:23887758

  2. The relation of oxygen intake and speed in competition cycling and comparative observations on the bicycle ergometer.

    PubMed

    Pugh, L G

    1974-09-01

    1. The relation of V(O2) and speed was determined on six competition cyclists riding at speeds ranging from 12 km/hr to 41 km/hr on the runway of an airfield. Comparative measurements were made on the bicycle ergometer to determine the corresponding work rates, and from this information rolling resistance and air resistance were derived.2. V(O2) was a curvilinear function of cycling speed, and increased from 0.88 l./min at 12.5 km/hr to 5.12 l./min at 41 km/hr, mean body weight being 72.9 kg.3. On the ergometer, V(O2) was a linear function of work rate; maximum values up to 5.1 l./min (74.4 ml./kg min) and work rates up to 425 W (2600 kg m/min) were observed.4. Data are presented on the relation of pedal frequency and speed in cycling, and on the relation of mechanical efficiency and pedal frequency, as determined on the ergometer.5. The estimated rolling resistance for four subjects was 0.71 kg f. The drag coefficient was 0.79 and the drag area 0.33 m(2). The values agreed well with results obtained by other methods.6. The energy expenditure (power developed) in cycling increased approximately as the square of the speed, and not as the cube of the speed as expected. This was explained by the varying contribution of rolling resistance and air resistance to over-all resistance to motion at different speeds.

  3. The relation of oxygen intake and speed in competition cycling and comparative observations on the bicycle ergometer

    PubMed Central

    Pugh, L. G. C. E.

    1974-01-01

    1. The relation of V̇O2 and speed was determined on six competition cyclists riding at speeds ranging from 12 km/hr to 41 km/hr on the runway of an airfield. Comparative measurements were made on the bicycle ergometer to determine the corresponding work rates, and from this information rolling resistance and air resistance were derived. 2. V̇O2 was a curvilinear function of cycling speed, and increased from 0·88 l./min at 12·5 km/hr to 5·12 l./min at 41 km/hr, mean body weight being 72·9 kg. 3. On the ergometer, V̇O2 was a linear function of work rate; maximum values up to 5·1 l./min (74·4 ml./kg min) and work rates up to 425 W (2600 kg m/min) were observed. 4. Data are presented on the relation of pedal frequency and speed in cycling, and on the relation of mechanical efficiency and pedal frequency, as determined on the ergometer. 5. The estimated rolling resistance for four subjects was 0·71 kg f. The drag coefficient was 0·79 and the drag area 0·33 m2. The values agreed well with results obtained by other methods. 6. The energy expenditure (power developed) in cycling increased approximately as the square of the speed, and not as the cube of the speed as expected. This was explained by the varying contribution of rolling resistance and air resistance to over-all resistance to motion at different speeds. PMID:4436817

  4. Design of a vibration isolation system for a cycle ergometer to be used onboard the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Pearson, Lillian; Tait, Steven; Trevino, Maurice

    1991-01-01

    Low frequency vibrations generated during exercise using the cycle ergometer onboard the Space Shuttle are disrupting sensitive microgravity experiments. The design team is asked by NASA/USRA to generate alternatives for the design of a vibration isolation system for the cycle ergometer. It is the design team's objective to present alternative designs and a problem solution for a vibration isolation system for an exercise cycle ergometer to be used onboard the Space Shuttle. In the development of alternative designs, the design team emphasizes passive systems as opposed to active control systems. This decision is made because the team feels that passive systems are less complex than active control systems, external energy sources are not required, and mass is reduced due to the lack of machinery such as servomotors or compressors typical of active control systems. Eleven alternative designs are developed by the design team. From these alternatives, three active control systems are included to compare the benefits of active and passive systems. Also included in the alternatives is an isolation system designed by an independent engineer that was acquired late in the project. The eight alternatives using passive isolation systems are narrowed down by selection criteria to four considered to be the most promising by the design team. A feasibility analysis is performed on these four passive isolation systems. Based on the feasibility analysis, a final design solution is chosen and further developed. From the development of the design, the design team has concluded that passive systems are not effective at isolating vibrations for the low frequencies considered for this project. Recommendations are made for guidelines of passive isolation design and application of such systems.

  5. Single-row vs. double-row arthroscopic rotator cuff repair: clinical and 3 Tesla MR arthrography results.

    PubMed

    Tudisco, Cosimo; Bisicchia, Salvatore; Savarese, Eugenio; Fiori, Roberto; Bartolucci, Dario A; Masala, Salvatore; Simonetti, Giovanni

    2013-01-27

    Arthroscopic rotator cuff repair has become popular in the last few years because it avoids large skin incisions and deltoid detachment and dysfunction. Earlier arthroscopic single-row (SR) repair methods achieved only partial restoration of the original footprint of the tendons of the rotator cuff, while double-row (DR) repair methods presented many biomechanical advantages and higher rates of tendon-to-bone healing. However, DR repair failed to demonstrate better clinical results than SR repair in clinical trials. MR imaging at 3 Tesla, especially with intra-articular contrast medium (MRA), showed a better diagnostic performance than 1.5 Tesla in the musculoskeletal setting. The objective of this study was to retrospectively evaluate the clinical and 3 Tesla MRA results in two groups of patients operated on for a medium-sized full-thickness rotator cuff tear with two different techniques. The first group consisted of 20 patients operated on with the SR technique; the second group consisted of 20 patients operated on with the DR technique. All patients were evaluated at a minimum of 3 years after surgery. The primary end point was the re-tear rate at 3 Tesla MRA. The secondary end points were the Constant-Murley Scale (CMS), the Simple Shoulder Test (SST) scores, surgical time and implant expense. The mean follow-up was 40 months in the SR group and 38.9 months in the DR group. The mean postoperative CMS was 70 in the SR group and 68 in the DR group. The mean SST score was 9.4 in the SR group and 10.1 in the DR group. The re-tear rate was 60% in the SR group and 25% in the DR group. Leakage of the contrast medium was observed in all patients. To the best of our knowledge, this is the first report on 3 Tesla MRA in the evaluation of two different techniques of rotator cuff repair. DR repair resulted in a statistically significant lower re-tear rate, with longer surgical time and higher implant expense, despite no difference in clinical outcomes. We think that

  6. [Biomechanical and physiological substantiation for application of functional muscle electrostimulation in performing rhythmic movements on bicycle ergometer].

    PubMed

    Petrushanskaia, K A; Vitenzon, A S; Gritsenko, G P; Sutchenkov, I A

    2004-01-01

    Kinematic and electromyographic parameters in conduction of rhythmic movements on the bicycle ergometer were studied in a group of healthy subjects. It is shown that these movements are characterized by a stable biomechanical and innervation stereotype consisting of two interacting synergies: flexor and extensor. Force extensor synergy plays the key role which provides both triggering and maintenance of certain rhythm of rotation. Flexor synergy is primarily corrective. Basing on the data obtained, stimulated muscles are selected in basic phases of the cycle, algorithms of time and amplitude programs of muscle electrostimulation in conduction of bicycle ergometry are proposed.

  7. Force-velocity relationship and maximal power on a cycle ergometer. Correlation with the height of a vertical jump.

    PubMed

    Vandewalle, H; Peres, G; Heller, J; Panel, J; Monod, H

    1987-01-01

    The force-velocity relationship on a Monark ergometer and the vertical jump height have been studied in 152 subjects practicing different athletic activities (sprint and endurance running, cycling on track and/or road, soccer, rugby, tennis and hockey) at an average or an elite level. There was an approximately linear relationship between braking force and peak velocity for velocities between 100 and 200 rev.min-1. The highest indices of force P0, velocity V0 and maximal anaerobic power (Wmax) were observed in the power athletes. There was a significant relationship between vertical jump height and Wmax related to body mass.

  8. The extension of a uniform canopy reflectance model to include row effects

    NASA Technical Reports Server (NTRS)

    Suits, G. H. (Principal Investigator)

    1981-01-01

    The effect of row structure is assumed to be caused by the variation in density of vegetation across rows rather than to a profile in canopy height. The calculation of crop reflectance using vegetation density modulation across rows follows a parallel procedure to that for a uniform canopy. Predictions using the row model for wheat show that the effect of changes in sun to row azimuth are greatest in Landsat Band 5 (red band) and can result in underestimation of crop vigor.

  9. Comparative cervical profiles of adult and under-18 front-row rugby players: implications for playing policy.

    PubMed

    Hamilton, D F; Gatherer, D; Robson, J; Graham, N; Rennie, N; Maclean, J G B; Simpson, A H R W

    2014-05-05

    To compare the cervical isometric strength, fatigue endurance and range of motion of adult and under-18 age-grade front-row rugby players to inform the development of a safe age group policy with particular reference to scrummaging. Cross-sectional cohort study. 'Field testing' at Murrayfield stadium. 30 high-performance under-18 players and 22 adult front-row rugby players. Isometric neck strength, height, weight and grip strength. Youth players demonstrated the same height and grip strength as the adult players; however, the adults were significantly heavier and demonstrated substantially greater isometric strength (p<0.001). Only two of the 'elite' younger players could match the adult mean cervical isometric strength value. In contrast to school age players in general, grip strength was poorly associated with neck strength (r=0.2) in front-row players; instead, player weight (r=0.4) and the number of years' experience of playing in the front row (r=0.5) were the only relevant factors in multivariate modelling of cervical strength (R(2)=0.3). Extreme forces are generated between opposing front rows in the scrum and avoidance of mismatch is important if the risk of injury is to be minimised. Although elite youth front-row rugby players demonstrate the same peripheral strength as their adult counterparts on grip testing, the adults demonstrate significantly greater cervical strength. If older youths and adults are to play together, such findings have to be noted in the development of age group policies with particular reference to the scrum.

  10. Validated biomechanical model for efficiency and speed of rowing.

    PubMed

    Pelz, Peter F; Vergé, Angela

    2014-10-17

    The speed of a competitive rowing crew depends on the number of crew members, their body mass, sex and the type of rowing-sweep rowing or sculling. The time-averaged speed is proportional to the rower's body mass to the 1/36th power, to the number of crew members to the 1/9th power and to the physiological efficiency (accounted for by the rower's sex) to the 1/3rd power. The quality of the rowing shell and propulsion system is captured by one dimensionless parameter that takes the mechanical efficiency, the shape and drag coefficient of the shell and the Froude propulsion efficiency into account. We derive the biomechanical equation for the speed of rowing by two independent methods and further validate it by successfully predicting race times. We derive the theoretical upper limit of the Froude propulsion efficiency for low viscous flows. This upper limit is shown to be a function solely of the velocity ratio of blade to boat speed (i.e., it is completely independent of the blade shape), a result that may also be of interest for other repetitive propulsion systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. 7 CFR 810.204 - Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... barley and Six-rowed Blue Malting barley. 810.204 Section 810.204 Agriculture Regulations of the... Standards for Barley Principles Governing the Application of Standards § 810.204 Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley. Grade Minimum limits of—...

  12. 7 CFR 810.204 - Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... barley and Six-rowed Blue Malting barley. 810.204 Section 810.204 Agriculture Regulations of the... Standards for Barley Principles Governing the Application of Standards § 810.204 Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley. Grade Minimum limits of—...

  13. 7 CFR 810.204 - Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... barley and Six-rowed Blue Malting barley. 810.204 Section 810.204 Agriculture Regulations of the... Standards for Barley Principles Governing the Application of Standards § 810.204 Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley. Grade Minimum limits of—...

  14. 7 CFR 810.204 - Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... barley and Six-rowed Blue Malting barley. 810.204 Section 810.204 Agriculture Regulations of the... Standards for Barley Principles Governing the Application of Standards § 810.204 Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley. Grade Minimum limits of—...

  15. 7 CFR 810.204 - Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... barley and Six-rowed Blue Malting barley. 810.204 Section 810.204 Agriculture Regulations of the... Standards for Barley Principles Governing the Application of Standards § 810.204 Grades and grade requirements for Six-rowed Malting barley and Six-rowed Blue Malting barley. Grade Minimum limits of—...

  16. Single-Row or Double-Row Fixation Technique for Full-Thickness Rotator Cuff Tears: A Meta-Analysis

    PubMed Central

    Zhou, Jiaojiao; Yuan, Chaoqun; Chen, Kai; Cheng, Biao

    2013-01-01

    Background The single-row and double-row fixation techniques have been widely used for rotator cuff tears. However, whether the double-row technique produces superior clinical or anatomic outcomes is still considered controversial. This study aims to use meta-analysis to compare the clinical and anatomical outcomes between the two techniques. Methods The Pubmed, Embase, and Cochrane library databases were searched for relevant studies published before November 1, 2012. Studies clearly reporting a comparison of the single-row and double-row techniques were selected. The Constant, ASES, and UCLA scale systems and the rotator cuff integrity rate were evaluated. The weighted mean differences and relative risks were calculated using a fixed-effects or random-effects model. Results Eight studies were included in this meta-analysis. The weighted mean differences of the ASES (−0.84; P = 0.04; I2 = 0%) and UCLA (−0.75; P = 0.007; I2 = 0%) scales were significantly low in the single-row group for full-thickness rotator cuff tears. For tear sizes smaller than 3 cm, no significant difference was found between the groups no matter in Constant (P = 0.95; I2 = 0%), ASES (P = 0.77; I2 = 0%), or UCLA (P = 0.24; I2 = 13%) scales. For tear sizes larger than 3 cm, the ASES (−1.95; P = 0.001; I2 = 49%) and UCLA (−1.17; P = 0.006; I2 = 0%) scales were markedly lower in the single-row group. The integrity of the rotator cuff (0.81; P = 0.0004; I2 = 10%) was greater and the partial thickness retear rate (1.93; P = 0.007; I2 = 10%) was less in the double-row group. Full-thickness retears showed no difference between the groups (P = 0.15; I2 = 0%). Conclusion The meta-analysis suggests that the double-row fixation technique increases post-operative rotator cuff integrity and improves the clinical outcomes, especially for full-thickness rotator cuff tears larger than 3 cm. For tear sizes smaller than 3 cm

  17. A parallelization of the row-searching algorithm

    NASA Astrophysics Data System (ADS)

    Yaici, Malika; Khaled, Hayet; Khaled, Zakia; Bentahar, Athmane

    2012-11-01

    The problem dealt in this paper concerns the parallelization of the row-searching algorithm which allows the search for linearly dependant rows on a given matrix and its implementation on MPI (Message Passing Interface) environment. This algorithm is largely used in control theory and more specifically in solving the famous diophantine equation. An introduction to the diophantine equation is presented, then two parallelization approaches of the algorithm are detailed. The first distributes a set of rows on processes (processors) and the second makes a distribution per blocks. The sequential algorithm and its two parallel forms are implemented using MPI routines, then modelled using UML (Unified Modelling Language) and finally evaluated using algorithmic complexity.

  18. Hydrodynamic characteristics of three rows of vertical slotted wall breakwaters

    NASA Astrophysics Data System (ADS)

    Alsaydalani, Majed O.; Saif, Mohammed A. N.; Helal, Medhat M.

    2017-09-01

    In this study, we examine the hydrodynamic characteristics of three rows of vertical slotted wall breakwaters in which the front and middle walls are permeable and partially immersed in a water channel of constant depth, whereas the third wall is impermeable. The wave-structure interaction and flow behavior of this type of breakwater arrangement are complicated and must be analyzed before breakwaters can be appropriately designed. To study the hydrodynamic breakwater performance, we developed a mathematical model based on the eigenfunction expansion method and a least squares technique for predicting wave interaction with three rows of vertical slotted wall breakwaters. We theoretically examined the wave transmission, reflection, energy loss, wave runup, and wave force under normal regular waves. Comparisons with experimental measurements show that the mathematical model results adequately reproduce most of the important features. The results of this investigation provide a better understanding of the hydrodynamic performance of triple-row vertical slotted wall breakwaters.

  19. Nutrition and Supplements for Elite Open-Weight Rowing.

    PubMed

    Boegman, Susan; Dziedzic, Christine E

    2016-01-01

    Competitive rowing events are raced over 2,000 m requiring athletes to have highly developed aerobic and anaerobic systems. Elite rowers therefore undertake training sessions focused on lactate tolerance, strength and power as well as aerobic and anaerobic capacity development, that can amount to a 24-h training week. The training stimuli and consequent metabolic demands of each session in a rowing training program differ depending on type, length, and intensity. Nutrition guidelines for endurance- and power-based sports should be drawn upon; however, individualized and flexible nutrition plans are critical to successfully meet the daily, weekly, and cyclic nutrient requirements of a rower. This review will provide an overview of key nutritional strategies to optimize training and enhance adaptation, and briefly discuss supplement strategies that may support health and enhance performance in elite rowing.

  20. Comparative cervical profiles of adult and under-18 front-row rugby players: implications for playing policy

    PubMed Central

    Hamilton, D F; Gatherer, D; Robson, J; Graham, N; Rennie, N; MacLean, J G B; Simpson, A H R W

    2014-01-01

    Objective To compare the cervical isometric strength, fatigue endurance and range of motion of adult and under-18 age-grade front-row rugby players to inform the development of a safe age group policy with particular reference to scrummaging. Design Cross-sectional cohort study. Setting ‘Field testing’ at Murrayfield stadium. Participants 30 high-performance under-18 players and 22 adult front-row rugby players. Outcome measures Isometric neck strength, height, weight and grip strength. Results Youth players demonstrated the same height and grip strength as the adult players; however, the adults were significantly heavier and demonstrated substantially greater isometric strength (p<0.001). Only two of the ‘elite’ younger players could match the adult mean cervical isometric strength value. In contrast to school age players in general, grip strength was poorly associated with neck strength (r=0.2) in front-row players; instead, player weight (r=0.4) and the number of years’ experience of playing in the front row (r=0.5) were the only relevant factors in multivariate modelling of cervical strength (R2=0.3). Conclusions Extreme forces are generated between opposing front rows in the scrum and avoidance of mismatch is important if the risk of injury is to be minimised. Although elite youth front-row rugby players demonstrate the same peripheral strength as their adult counterparts on grip testing, the adults demonstrate significantly greater cervical strength. If older youths and adults are to play together, such findings have to be noted in the development of age group policies with particular reference to the scrum. PMID:24797427

  1. Functional Outcomes After Double-Row Versus Single-Row Rotator Cuff Repair: A Prospective Randomized Trial.

    PubMed

    Nicholas, Stephen J; Lee, Steven J; Mullaney, Michael J; Tyler, Timothy F; Fukunaga, Takumi; Johnson, Christopher D; McHugh, Malachy P

    2016-10-01

    The functional benefits of double-row (DR) versus single-row (SR) rotator cuff repair are not clearly established. To examine the effect of DR versus SR rotator cuff repair on functional outcomes and strength recovery in patients with full-thickness tears. Randomized controlled trial; Level of evidence, 2. Forty-nine patients were randomized to DR or SR repairs; 36 patients (13 women, 23 men; mean age, 62 ± 7 years; 20 SR, 16 DR) were assessed at a mean 2.2 ± 1.6 years after surgery (range, 1-7 years; tear size: 17 medium, 13 large, 9 massive). The following data were recorded prior to surgery and at follow-up: Penn shoulder score, American Shoulder and Elbow Surgeons (ASES), and Simple Shoulder Test (SST) results; range of motion (ROM) for shoulder flexion, external rotation (ER) at 0° and 90° of abduction, and internal rotation (IR) at 90° of abduction; and shoulder strength (Lafayette manual muscle tester) in empty- and full-can tests, abduction, and ER at 0° of abduction. Treatment (SR vs DR) × time (pre- vs postoperative) mixed-model analysis of variance was used to assess the effect of rotator cuff repair. Rotator cuff repair markedly improved Penn, ASES, and SST scores (P < .001), with similar improvement between SR and DR repairs (treatment × time, P = .38-.10) and excellent scores at follow-up (DR vs SR: Penn, 91 ± 11 vs 92 ± 11 [P = .73]; ASES, 87 ± 12 vs 92 ± 12 [P = .21]; SST, 11.4 ± 1.0 vs 11.3 ± 1.0 [P = .76]). Patients with DR repairs lost ER ROM at 0° of abduction (preoperative to final follow-up, 7° ± 10° loss [P = .013]). ER ROM did not significantly change with SR repair (5° ± 14° gain, P = .16; treatment by time, P = .008). This effect was not apparent for ER ROM at 90° of abduction (treatment × time, P = .26). IR ROM improved from preoperative to final follow-up (P < .01; SR, 17° ± 27°; DR, 7° ± 21°; treatment × time, P = .23). Rotator cuff repair markedly improved strength in empty-can (54%), full-can (66

  2. 4. ROW OF SPARE THREEHIGH ROLL STANDS ADJACENT TO THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. ROW OF SPARE THREE-HIGH ROLL STANDS ADJACENT TO THE 32/28 STRUCTURAL MILL. AN OVERHEAD CRANE LIFTED THESE STANDS INTO PLACE ON THE 32/28 MILL. - U.S. Steel Homestead Works, Structural Mill, Along Monongahela River, Homestead, Allegheny County, PA

  3. Effect of row orientation on energy balance components

    USDA-ARS?s Scientific Manuscript database

    Solar irradiance is the primary source of energy that is converted into sensible and latent heat fluxes in the soil-plant-atmosphere continuum. The orientation of agricultural crop rows relative to the sun’s zenith angle determines the amount of solar irradiance reaching the plant and soil surfaces...

  4. Relation of baseflow to row crop intensity in Iowa

    USGS Publications Warehouse

    Schilling, K.E.

    2005-01-01

    Increasing baseflow and baseflow percentage over the second half of the 20th century in Iowa has contributed to increasing nitrate-nitrogen concentrations measured in Iowa rivers because nitrate is primarily delivered to streams as baseflow and tile drainage. The relation of baseflow and baseflow percentage to row crop land use was evaluated for 11 Iowa rivers and their watersheds for their period of streamflow record (58-73 years period). Results indicated increasing baseflow in Iowa's rivers is significantly related to increasing row crop intensity. A 13-52% increase in row crop percentage in many Iowa watersheds has contributed to an increase of 33-135 mm increase in baseflow and 7-31% increase in baseflow percentage. Limited historical water quality data from two larger Iowa rivers (Cedar and Raccoon rivers) suggest that increasing row crop land use over the 20th century has produced more baseflow and contributed to increasing nitrate concentrations in Iowa's rivers. ?? 2004 Elsevier B.V. All rights reserved.

  5. Interior view to the east, note the row of transmitters ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view to the east, note the row of transmitters and the cables in the foreground - Over-the-Horizon Backscatter Radar Network, Christmas Valley Radar Site Transmit Sector Six Transmitter Building, On unnamed road west of Lost Forest Road, Christmas Valley, Lake County, OR

  6. Cotton Response to Herbicide Technologies, Row Patterns, and Tillage Systems

    USDA-ARS?s Scientific Manuscript database

    Cotton producers must make decisions related to cotton varieties, herbicide systems, tillage systems, and row patterns. A study was conducted to compare a conventional variety, a glyphosate tolerant variety, and a glufosinate tolerant variety in both conventional tillage and conservation tillage sys...

  7. Illinois Occupational Skill Standards: Row Crop Production Cluster.

    ERIC Educational Resources Information Center

    Illinois Occupational Skill Standards and Credentialing Council, Carbondale.

    This document, which is intended as a guide for work force preparation program providers, details the Illinois occupational skill standards for programs preparing students for employment in occupations in the row crop production cluster. The document begins with a brief overview of the Illinois perspective on occupational skill standards and…

  8. 102. VIEW OF WEST ROW OF CABINETS IN LANDLINE INSTRUMENTATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    102. VIEW OF WEST ROW OF CABINETS IN LANDLINE INSTRUMENTATION ROOM (106), LSB (BLDG. 770). LOGIC CONTROL AND MONITOR UNITS BOOSTER AND FUEL SYSTEMS ON LEFT; LANDLINE SIGNAL CONDITIONERS ON RIGHT. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  9. A mathematical model concerning reflectance from a row crop

    NASA Technical Reports Server (NTRS)

    Jaggi, R. K.

    1972-01-01

    The recent work of Allen, Gayle, and Richardson (1970) and Suits (1972) has been extended to compute directional reflectance from a crop row. A model is constructed which takes into account edge effects and aids in discriminating crops with leaf orientation in preferred directions. This report only contains the development of the mathematical equations. Numerical results will be published in a forthcoming report.

  10. Power, Consent and Resistance: An Autoethnography of Competitive Rowing

    ERIC Educational Resources Information Center

    Purdy, Laura; Potrac, Paul; Jones, Robyn

    2008-01-01

    This study builds upon existing socio-cultural work into sports coaching by probing the meanings and varieties of the shared coach-athlete experience. Specifically, the paper utilises an autoethnographic approach in an attempt to chart the complex and dynamic relationship that existed between me, the principal author, as a rowing coxswain and my…

  11. 1. Elevator row at Duluth. Rice's Point showing context of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Elevator row at Duluth. Rice's Point showing context of Peavey Duluth Terminal and Occident Terminal. - Peavey Duluth Terminal Elevator, South side of first slip, north from outer end of Rice's Point, east of Garfield Avenue, Duluth, St. Louis County, MN

  12. Strip tillage for single and twin-row peanut

    USDA-ARS?s Scientific Manuscript database

    Soil degradation and rising production costs have prompted grower interest in conservation tillage with high residue cover crops for peanut (Arachis hypogaea L.). The objective was to evaluate single and twin-row peanut production across three different strip tillage implements with and without a c...

  13. Cervical range of motion, cervical and shoulder strength in senior versus age-grade Rugby Union International front-row forwards.

    PubMed

    Davies, Mark; Moore, Isabel S; Moran, Patrick; Mathema, Prabhat; Ranson, Craig A

    2016-05-01

    To provide normative values for cervical range of motion (CROM), isometric cervical and shoulder strength for; International Senior professional, and International Age-grade Rugby Union front-row forwards. Cross-sectional population study. All international level front-row players within a Rugby Union Tier 1 Nation. Nineteen Senior and 21 Age-grade front-row forwards underwent CROM, cervical and shoulder strength testing. CROM was measured using the CROM device and the Gatherer System was used to measure multi-directional isometric cervical and shoulder strength. The Age-grade players had significantly lower; cervical strength (26-57% deficits), cervical flexion to extension strength ratios (0.5 vs. 0.6), and shoulder strength (2-36% deficits) than the Senior players. However, there were no differences between front-row positions within each age group. Additionally, there were no differences between age groups or front-row positions in the CROM measurements. Senior Rugby Union front-row forwards have greater cervical and shoulder strength than Age-grade players, with the biggest differences being in cervical strength, highlighting the need for age specific normative values. Importantly, Age-grade players should be evaluated to ensure they have developed sufficient cervical strength prior to entering professional level Rugby Union. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Sports biomechanics in the research of the Department of Biomechanics of University School of Physical Education in Poznań. Part 2. Biomechanics of rowing: research conducted in the rowing pool and under real conditions. Reconstruction and synthesis.

    PubMed

    Dworak, Lechosław B

    2010-01-01

    The purpose of this study was to reconstruct the early phase of scientific research conducted at the Department of Biomechanics of the College of Physical Education and since 1972 at the University School of Physical Education in Poznań, with special attention paid to the works on biomechanics of rowing, carried out as part of the Ministerial Project PR 105 entitled The effectiveness of training, sports competition as well as regeneration in sports. Two kinds of biomechanical research are described: the several years' expert research conducted on the Rowing National Team in an original two-module Rowing Pool Testing Station BTW-1, as well as research on geometric optimization of the rowing station, conducted under real conditions, in reservoirs, with the use of a prototypical, unique at that time, computer measurement system BIOMIK, installed in the rower's own boat. The projects were carried out by doctoral students from the Department of Biomechanics and the Department of Clinical Biomechanics, Andrzej Lisiecki and Wojciech Mikołajczyk, respectively.

  15. A simple ergometer for 31P NMR spectroscopy during dynamic forearm exercise in a whole body magnetic resonance imaging system.

    PubMed

    Nishijima, H; Nishida, M; Anzai, T; Yonezawa, K; Fukuda, H; Sato, I; Yasuda, H

    1992-03-01

    The purpose of this study was to construct a simple ergometer for the 31P NMR spectroscopic study of dynamic forearm exercise in a whole body magnetic resonance imaging system and to evaluate the total system and the physiological response to this type of exercise using a multistage protocol. The system consisted of a completely nonmagnetic assembly including a rope, pulley and weights. The work of lifting weights was quantitated. The exercise protocol of 1-min increments in work load enabled subjects to reach maximal effort. Phosphocreatine decreased linearly with an increase in work load and was accompanied by a fall in pH and an increase in lactate level in the antecubital vein of the exercising forearm; concomitantly, there was a slight increase in whole body oxygen uptake and heart rate. Spectroscopy gave reproducible results using this exercise protocol. These results demonstrate that this system provides a reliable means for performing 31P magnetic resonance spectroscopy studies during forearm exercise.

  16. Accelerated cardiac MR stress perfusion with radial sampling after physical exercise with an MR-compatible supine bicycle ergometer.

    PubMed

    Pflugi, Silvio; Roujol, Sébastien; Akçakaya, Mehmet; Kawaji, Keigo; Foppa, Murilo; Heydari, Bobby; Goddu, Beth; Kissinger, Kraig; Berg, Sophie; Manning, Warren J; Kozerke, Sebastian; Nezafat, Reza

    2015-08-01

    To evaluate the feasibility of accelerated cardiac MR (CMR) perfusion with radial sampling using nonlinear image reconstruction after exercise on an MR-compatible supine bike ergometer. Eight healthy subjects were scanned on two separate days using radial and Cartesian CMR perfusion sequences in rest and exercise stress perfusion. Four different methods (standard gridding, conjugate gradient SENSE [CG-SENSE], nonlinear inversion with joint estimation of coil-sensitivity profiles [NLINV] and compressed sensing with a total variation constraint [TV]) were compared for the reconstruction of radial data. Cartesian data were reconstructed using SENSE. All images were assessed by two blinded readers in terms of image quality and diagnostic value. CG-SENSE and NLINV were scored more favorably than TV (in both rest and stress perfusion cases, P < 0.05) and gridding (for rest perfusion cases, P < 0.05). TV images showed patchy artifacts, which negatively influenced image quality especially in the stress perfusion images acquired with a low number of radial spokes. Although CG-SENSE and NLINV received better scores than Cartesian sampling in both rest and exercise stress perfusion cases, these differences were not statistically significant (P > 0.05). We have demonstrated the feasibility of accelerated CMR perfusion using radial sampling after physical exercise using a supine bicycle ergometer in healthy subjects. For reconstruction of undersampled radial perfusion, CG-SENSE and NLINV resulted in better image quality than standard gridding or TV reconstruction. Further technical improvements and clinical assessment are needed before using this approach in patients with suspected coronary artery disease. © 2014 Wiley Periodicals, Inc.

  17. Work and power outputs determined from pedalling and flywheel friction forces during brief maximal exertion on a cycle ergometer.

    PubMed

    Hibi, N; Fujinaga, H; Ishii, K

    1996-01-01

    Work and power outputs during short-term, maximal exertion on a friction loaded cycle ergometer are usually calculated from the friction force applied to the flywheel. The inertia of the flywheel is sometimes taken into consideration, but the effects of internal resistances and other factors have been ignored. The purpose of this study was to estimate their effects by comparing work or power output determined from the force exerted on the pedals (pedalling force) with work or power output determined from the friction force and the moment of inertia of the rotational parts. A group of 22 male college students accelerated a cycle ergometer as rapidly as possible for 3 s. The total work output determined from the pedalling force (TWp) was significantly greater than that calculated from the friction force and the moment of inertia (TWf). Power output determined from the pedalling force during each pedal stroke (SPp) was also significantly greater than that calculated from the friction force and the moment of inertia. Percentage difference (% diff), defined by % diff = ¿(TWp - TWf)/TWf¿ x 100, ranged from 16.8% to 49.3% with a mean value of 30.8 (SD 9.1)%. It was observed that % diff values were higher in subjects with greater TWp or greater maximal SPp. These results would indicate that internal resistances and other factors, such as the deformation of the chain and the vibrations of the entire system, may have significant effects on the measurements of work and power outputs. The effects appear to depend on the magnitudes of pedalling force and pedal velocity.

  18. Effects of Indoor Rowing Exercise on the Body Composition and the Scoliosis of Visually Impaired People: A Preliminary Study

    PubMed Central

    Shin, Ka-Young; Lim, Jong-Youb; Cho, Ah-Ra; Lim, Young-Ho

    2015-01-01

    Objective To evaluate the effects of rowing exercise on body composition, laboratory data, fitness and scoliosis in visually impaired people. The majority of visually impaired people do not participate in active sports due to efficiency and safety issues. Rowing is a safe whole-body exercise with aerobic and anaerobic components. Methods Twenty subjects were recruited from among those admitted to a facility for visually impaired people (16 men and 4 women). Laboratory data, body composition, physical fitness, Cobb's angle, and fall index were checked before and after 6 weeks (5 days a week) of indoor rowing using Concept2 Model E. Results After the training, fat mass and total body fat percent decreased significantly. In the fitness test, back strength and trunk flexion score increased significantly. Laboratory data showed significant increases in serum protein and albumin and decreases in low-density lipoprotein (LDL) cholesterol. There were 9 subjects with scoliosis and after the training Cobb's angle decreased by 1.11°±1.55°, though this was not statistically significant. Conclusion Visually impaired people frequently have abnormal body composition, low physical fitness, and scoliosis. A rowing exercise program can be helpful, with a positive effect on body composition and physical fitness; however, with respect to scoliosis, we need an earlier intervention program in visually impaired people. PMID:26361596

  19. An experimental study on refrigerant distribution in a two row/four pass parallel flow minichannel heat exchanger

    NASA Astrophysics Data System (ADS)

    Byun, Ho-Won; Kim, Nae-Hyun

    2016-10-01

    R-410A distribution was experimentally studied for a parallel flow evaporator having two row/four pass configuration. The evaporator has inlet, intermediate and row-crossing headers. Tests were conducted for the mass flux from 70 to 130 kg/m2s with the quality at the inlet of 0.2 and exit superheat 5 °C. Significant heat transfer degradation (13-40 %) was realized for the two row/four pass configuration due to flow mal-distribution. Of the three insert hole sizes, 4.0 mm hole yielded the least heat transfer degradation followed by 6.0 and 2.0 mm holes. At the inlet header, more liquid flowed into upstream channels. At the intermediate headers, more liquid was supplied into downstream channels. Similar flow distribution was obtained before and after the row crossing header. Header pressure drops were obtained by subtracting the flat tube pressure drops and other minor pressure drops from measured pressure drops.

  20. Study of Low Reynolds Number Effects on the Losses in Low-Pressure Turbine Blade Rows

    NASA Technical Reports Server (NTRS)

    Ashpis, David E.; Dorney, Daniel J.

    1998-01-01

    Experimental data from jet-engine tests have indicated that unsteady blade row interactions and separation can have a significant impact on the efficiency of low-pressure turbine stages. Measured turbine efficiencies at takeoff can be as much as two points higher than those at cruise conditions. Several recent studies have revealed that Reynolds number effects may contribute to the lower efficiencies at cruise conditions. In the current study numerical experiments have been performed to study the models available for low Reynolds number flows, and to quantify the Reynolds number dependence of low-pressure turbine cascades and stages. The predicted aerodynamic results exhibit good agreement with design data.

  1. The Effect of Bicycle Ergometer Exercise at Varying Intensities on the Heart Rate, EMG and Mood State Responses to a Mental Arithmetic Stressor.

    ERIC Educational Resources Information Center

    McGowan, Colleen R.; And Others

    1985-01-01

    This study examined the effect of bicycle ergometer exercise at varying metabolic intensities upon the heart rate, electromyographic (EMG), and mood state responses to a timed mental arithmetric stressor of 12 adult males. Exercise influenced heart rate and EMG but not physiological and psychological responses to the arithmetic stressor.…

  2. The Effect of Bicycle Ergometer Exercise at Varying Intensities on the Heart Rate, EMG and Mood State Responses to a Mental Arithmetic Stressor.

    ERIC Educational Resources Information Center

    McGowan, Colleen R.; And Others

    1985-01-01

    This study examined the effect of bicycle ergometer exercise at varying metabolic intensities upon the heart rate, electromyographic (EMG), and mood state responses to a timed mental arithmetric stressor of 12 adult males. Exercise influenced heart rate and EMG but not physiological and psychological responses to the arithmetic stressor.…

  3. Simulation of design-unbiased point-to-particle sampling compared to alternatives on plantation rows

    Treesearch

    Thomas B. Lynch; David Hamlin; Mark J. Ducey

    2016-01-01

    Total quantities of tree attributes can be estimated in plantations by sampling on plantation rows using several methods. At random sample points on a row, either fixed row lengths or variable row lengths with a fixed number of sample trees can be assessed. Ratio of means or mean of ratios estimators can be developed for the fixed number of trees option but are not...

  4. Alternate row placement is ineffective for cultural control of Meloidogyne incognita in cotton

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to determine if planting cotton into the space between the previous year's rows reduces crop loss due to nematodes compared to planting in the same row every year. Row placement had a significant (P = 0.05) effect on nematode counts only on 8 July 2005. Plots receiv...

  5. Row-Sum of a Class of M-Bonomial Coefficients

    ERIC Educational Resources Information Center

    Asiru, Muniru A.

    2011-01-01

    Formulae for row-sum of M-bonomial coefficients [image omitted] where G is an mth g-gonal number is developed from a study of the ratio between consecutive terms of the sequence of row-sum. The result generalizes the formula for row-sum of binomial coefficients: [image omitted].

  6. Row Spacing and Plant Population Effects on Cotton Produced With or Without Irrigation

    USDA-ARS?s Scientific Manuscript database

    Field studies were conducted from 2006 through 2008 to evaluate the effects of twin-row spacings, populations, and irrigation on cotton (Gossypium hirsutum L.) lint yields. Twin row systems, consisting of twin 18-, 25- and 38-cm rows on a 1-m bed at populations of 111,000 and 148,000 plants/acre, w...

  7. Growth and yield of valencia, spanish, virginia and runner market type peanuts in various row spacings

    USDA-ARS?s Scientific Manuscript database

    Currently, the majority of peanuts grown in New Mexico and West Texas are planted in single rows on beds 36 to 40 inches apart. In 2006-2008, several field studies were conducted with Valencia peanuts comparing single row, twin row, and diamond planting patterns in various populations. The basic c...

  8. Cultural practices to improve in-row weed control with cultivation in organic peanut production

    USDA-ARS?s Scientific Manuscript database

    Cultivation is a proven effective means of weed control in organic peanut. However, weeds in-row often escape control. Research trials were conducted in Ty Ty, GA to modify cultural practices to help peanut suppress weed emergence in-row. Modified cultural practices were three row pattern/seeding...

  9. 32. TYPICAL BRYANT ITEMS FROM THE 1930S; TOP ROW LEFT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. TYPICAL BRYANT ITEMS FROM THE 1930S; TOP ROW LEFT TO RIGHT: PORCELAIN CASED SWITCH, ROTARY SWITCH, SHORTING PLUG TO BYPASS FUSE; SECOND ROW: BRASS INCANDESCENT LAMP SURFACE RECEPTACLE, INCANDESCENT LAMPHOLDER WITH ADAPTER FOR GLASS GLOBE; THIRD ROW: PORCELAIN BASE ROTARY SWITCH, APPLIANCE BREAKER WITH COVER REMOVED, APPLIANCE BREAKER - Bryant Electric Company, 1421 State Street, Bridgeport, Fairfield County, CT

  10. Row-Sum of a Class of M-Bonomial Coefficients

    ERIC Educational Resources Information Center

    Asiru, Muniru A.

    2011-01-01

    Formulae for row-sum of M-bonomial coefficients [image omitted] where G is an mth g-gonal number is developed from a study of the ratio between consecutive terms of the sequence of row-sum. The result generalizes the formula for row-sum of binomial coefficients: [image omitted].

  11. Effects of 16-week high-intensity interval training using upper and lower body ergometers on aerobic fitness and morphological changes in healthy men: a preliminary study

    PubMed Central

    Osawa, Yusuke; Azuma, Koichiro; Tabata, Shogo; Katsukawa, Fuminori; Ishida, Hiroyuki; Oguma, Yuko; Kawai, Toshihide; Itoh, Hiroshi; Okuda, Shigeo; Matsumoto, Hideo

    2014-01-01

    It is unclear whether combined leg and arm high-intensity interval training (HIIT) improves fitness and morphological characteristics equal to those of leg-based HIIT programs. The aim of this study was to compare the effects of HIIT using leg-cycling (LC) and arm-cranking (AC) ergometers with an HIIT program using only LC. Effects on aerobic capacity and skeletal muscle were analyzed. Twelve healthy male subjects were assigned into two groups. One performed LC-HIIT (n=7) and the other LC- and AC-HIIT (n=5) twice weekly for 16 weeks. The training programs consisted of eight to 12 sets of >90% VO2 (the oxygen uptake that can be utilized in one minute) peak for 60 seconds with a 60-second active rest period. VO2 peak, watt peak, and heart rate were measured during an LC incremental exercise test. The cross-sectional area (CSA) of trunk and thigh muscles as well as bone-free lean body mass were measured using magnetic resonance imaging and dual-energy X-ray absorptiometry. The watt peak increased from baseline in both the LC (23%±38%; P<0.05) and the LC–AC groups (11%±9%; P<0.05). The CSA of the quadriceps femoris muscles also increased from baseline in both the LC (11%±4%; P<0.05) and the LC–AC groups (5%±5%; P<0.05). In contrast, increases were observed in the CSA of musculus psoas major (9%±11%) and musculus anterolateral abdominal (7%±4%) only in the LC–AC group. These results suggest that a combined LC- and AC-HIIT program improves aerobic capacity and muscle hypertrophy in both leg and trunk muscles. PMID:25395872

  12. Zonal wavefront sensor with reduced number of rows in the detector array.

    PubMed

    Boruah, Bosanta R; Das, Abhijit

    2011-07-10

    In this paper, we describe a zonal wavefront sensor in which the photodetector array can have a smaller number of rows. The test wavefront is incident on a two-dimensional array of diffraction gratings followed by a single focusing lens. The periodicity and the orientation of the grating rulings of each grating can be chosen such that the +1 order beam from the gratings forms an array of focal spots in the detector plane. We show that by using a square array of zones, it is possible to generate an array of +1 order focal spots having a smaller number of rows, thus reducing the height of the required detector array. The phase profile of the test wavefront can be estimated by measuring the displacements of the +1 order focal spots for the test wavefront relative to the +1 order focal spots for a plane reference wavefront. The narrower width of the photodetector array can offer several advantages, such as a faster frame rate of the wavefront sensor, a reduced amount of cross talk between the nearby detector zones, and a decrease in the maximum thermal noise. We also present experimental results of a proof-of-concept experimental arrangement using the proposed wavefront sensing scheme.

  13. Canopy Apparent Photosynthetic Characteristics and Yield of Two Spike-Type Wheat Cultivars in Response to Row Spacing under High Plant Density

    PubMed Central

    Cai, Tie

    2016-01-01

    R2 and R3 treatments. At the same time, a longer duration of CAP and green leaf area was maintained in R1 during grain filling. Compared with conventional row spacing, Wennong6 in R1 treatment obtained 21.0% and 19.1% higher grain yield in 2011 and 2012, respectively, while for Jimai22 it increased by 11.3% and 11.4%, respectively. A close association of yield with CAP and LAI at mid-grain filling was observed. In conclusion, for the tested growing conditions, decreasing the row spacing to an optimal distance (15 cm) maintained a longer duration of LAI and CAP during grain filling, made a better coordination of group and individual leaf photosynthesis, and accumulated higher aboveground biomass, leading to a greater grain yield. In addition, Wennong6 had a more rational canopy architecture than Jimai22 (improved LT and higher LAI) and CAP under 15-cm row spacing, leading to a higher grain yield, which indicated that the large-spike type cultivar has the potential to obtain higher yields by increasing plant density through optimum row spacing allocation (15 cm). PMID:26845330

  14. Canopy Apparent Photosynthetic Characteristics and Yield of Two Spike-Type Wheat Cultivars in Response to Row Spacing under High Plant Density.

    PubMed

    Liu, Tiening; Wang, Zhenlin; Cai, Tie

    2016-01-01

    R2 and R3 treatments. At the same time, a longer duration of CAP and green leaf area was maintained in R1 during grain filling. Compared with conventional row spacing, Wennong6 in R1 treatment obtained 21.0% and 19.1% higher grain yield in 2011 and 2012, respectively, while for Jimai22 it increased by 11.3% and 11.4%, respectively. A close association of yield with CAP and LAI at mid-grain filling was observed. In conclusion, for the tested growing conditions, decreasing the row spacing to an optimal distance (15 cm) maintained a longer duration of LAI and CAP during grain filling, made a better coordination of group and individual leaf photosynthesis, and accumulated higher aboveground biomass, leading to a greater grain yield. In addition, Wennong6 had a more rational canopy architecture than Jimai22 (improved LT and higher LAI) and CAP under 15-cm row spacing, leading to a higher grain yield, which indicated that the large-spike type cultivar has the potential to obtain higher yields by increasing plant density through optimum row spacing allocation (15 cm).

  15. Reliability of Upright and Supine Power Measurements Using an Inertial Load Cycle Ergometer

    NASA Technical Reports Server (NTRS)

    Wickwire, P. J.; Leach, M.; Ryder, J.; Ploutz-Snyder, R.; Ploutz-Snyder, L.

    2011-01-01

    Practical, reliable, and time efficient methods of measuring muscular power are desirable for both research and applied testing situations. The inertial-load cycling method (ILC; Power/Cycle, Austin, TX) requires subjects to pedal as fast as possible against the inertial load of a flywheel for only 3-5 seconds, which could help reduce the time and effort required for maximal power testing. PURPOSE: 1) To test the intramachine reliability of ILC over 3 separate sessions, 2) to compare postural stance (upright vs. supine) during testing, and 3) to compare the maximal power (Pmax) output measured using ILC to that obtained from traditional isokinetic and leg press testing. METHODS: Subjects (n = 12) were tested on 4 non-consecutive days. The following tests were done on the first day of testing: isometric knee extension, isokinetic knee extension at several speeds, isokinetic power/endurance at 180/sec (Biodex System 4), leg press maximal isometric force, and leg press power/endurance. The other 3 days consisted exclusively of ILC testing. Subjects performed 6 ILC tests in an upright position and 6 ILC tests in a supine position on each day. The starting position was counterbalanced. Mixed-effects linear modeling was used to determine if any differences existed between testing days and between upright and supine for Pmax and revolutions per minute at Pmax (RPMpk). Mixed-modeling was also used to calculate intraclass correlation coefficients (ICC) to determine the reliability of the ILC on each testing day for Pmax and RPMpk (ICCs were calculated separately for upright and supine). gKendall fs Tau a h was used to determine the association between ILC Pmax and isokinetic and leg press data. RESULTS: For Pmax, significant differences were found between days 1 and 2 (upright: p = 0.018; supine: p = 0.014) and between days 1 and 3 (upright: p = 0.001; supine: p = 0.002), but not between days 2 and 3 (upright: p = 0.422; supine: p = 0.501). Pmax ICC values were greater than

  16. The Cross-Validation of the United States Air Force Submaximal Cycle Ergometer Test to Estimate Aerobic Capacity

    DTIC Science & Technology

    1994-06-01

    orthopaedic limitations to exercise, pregnancy , blood donation within 15 days of the first visit, use of beta-blocker drugs or beta-agonist asthma medication...Anemia Arthritis Asthma - -_ Back injury or problem - -_ Blood clots Bronchitis - _ Cirrhosis - -_ Claudication - -. Elbow or shoulder problems...obesity/overweight - -_ Phlebitis Prostate trouble -.- ~ Rheumatic fever - Seizure disorder - -_ Stomach disease - Thyroid disease -_ _ Tumors or

  17. Skid-row rescue missions: A religious approach to alcoholism.

    PubMed

    Fagan, R W

    1987-06-01

    The focus of this study is on the religious service at which many skid-row rescue missions require attendance to receive benefits. Data were obtained from an observation study of thirty-seven skid-row rescue missions in Los Angeles and Seattle, interviews with ten mission directors, and mission newsletters. The missions use material benefits to attract potential converts. The theme of spiritual conversion is predominant in the mission service (sermons, songs, testimonies). Mission personnel feel they have been called by God, often have backgrounds similar to the people they serve, and view the skid rowers' problems as primarily personal and spiritual. Skid rowers resent the use of religion as bait, view their problems as primarily structural, and use the missions only as a last resort. The missions need to be compared to other alcoholism rehabilitation and religious institutions. A key component to their continued existence is outside Christian supporters.

  18. High Energy-Efficiency Retrofits to Baltimore's Row Homes

    SciTech Connect

    Chalk, J.; Johnson, A.L.; Lipscomb, L.; Wendt, R.

    1999-04-19

    The purpose of the research project is to develop high-perfommnce, energy-eflicient retrofits of existing row homes in Baltimore, Maryland. These efficiency enhancements are to optimize building envelope improvements, mechanical equipment improvements and operational improvements to the highest cost-effective level. Furthermore, this project is to investigate and demonstrate the impact of high-performance energy-efficiency retrofit improvements on row homes in the Historic East area of Baltimore. Three homes awaiting renovation are planned to receive building envelope, mechanical system, and electrical system improvements that will improve their energy petiormance. An incremental additional cost ceiling of $4000 for the energy eftlciency improvements, beyond those normally installed, has been set by the project.

  19. A parallel householder tridiagonalization stratagem using scattered row decomposition

    NASA Technical Reports Server (NTRS)

    Chang, H. Y.; Utku, S.; Salama, M.; Rapp, D.

    1988-01-01

    Householder's method for tridiagonalizing a real symmetric matrix, a major step in evaluating eigenvalues of the matrix, is modified into a parallel algorithm for a concurrent machine of message passing type. Each processor of the concurrent machine has its own CPU, communications control and local memory. Messages are passed through connections between processors. Although the basic algorithm is inherently serial, the computations can be spread over all processors by scattering different rows of the matrix into processors, hence the term 'Scattered Row Decomposition'. The steps in the serial and the parallel algorithms are identified. Expressions for efficiency and speedup are given in terms of problem and machine parameters. For a concurrent machine of ring type interconnection, a selected representative problem of large order exhibits efficiency approaching 66 per cent.

  20. Bilateral Second Carpal Row Duplication Associated with Multiple Epiphyseal Dysplasia

    PubMed Central

    Cladiere-Nassif, Victoire; Delaroche, Caroline; Pottier, Edwige; Feron, Jean-Marc

    2015-01-01

    We report a case of a 75-year-old woman presenting a hitherto undescribed condition of bilateral second carpal row duplication. She was diagnosed in childhood with both Marfan and Ehlers-Danlos syndromes, with no clear evidence and no further medical follow-up. She presented throughout her life with various articular symptoms, which appeared to be compatible with a diagnosis of multiple epiphyseal dysplasia, and underwent several surgical procedures on her knees and hips. Most recently, she was reporting pain at the base of the fifth metacarpal bone of the left hand. X-ray images and computed tomography (CT) were obtained for exploration and showed a total second row duplication in both carpi, with a total number of 18 carpal bones in each wrist. PMID:26649258

  1. Optimisation of the mean boat velocity in rowing.

    PubMed

    Rauter, G; Baumgartner, L; Denoth, J; Riener, R; Wolf, P

    2012-01-01

    In rowing, motor learning may be facilitated by augmented feedback that displays the ratio between actual mean boat velocity and maximal achievable mean boat velocity. To provide this ratio, the aim of this work was to develop and evaluate an algorithm calculating an individual maximal mean boat velocity. The algorithm optimised the horizontal oar movement under constraints such as the individual range of the horizontal oar displacement, individual timing of catch and release and an individual power-angle relation. Immersion and turning of the oar were simplified, and the seat movement of a professional rower was implemented. The feasibility of the algorithm, and of the associated ratio between actual boat velocity and optimised boat velocity, was confirmed by a study on four subjects: as expected, advanced rowing skills resulted in higher ratios, and the maximal mean boat velocity depended on the range of the horizontal oar displacement.

  2. Astronaut Hammond gets microgravity exercise on rowing machine

    NASA Image and Video Library

    1994-09-10

    STS064-09-026 (9-20 Sept. 1994) --- Astronaut L. Blaine Hammond, STS-64 pilot, gets microgravity exercise on the rowing machine. This area of the space shuttle Discovery's middeck was also used for the treadmill exercising device. Blaine and five other NASA astronauts spent almost 11 days in Earth orbit in support of the mission. Photo credit: NASA or National Aeronautics and Space Administration

  3. A review of turbomachinery blade-row interaction research

    NASA Technical Reports Server (NTRS)

    Smith, Todd E.

    1988-01-01

    Analytical and experimental research in the area of unsteady aerodynamics of turbomachinery has conventionally been applied to blading which oscillates when placed in a uniformly flowing fluid. Comparatively less effort has been offered for the study of blading which is subjected to nonuniformities within the flow field. The fluid dynamic environment of a blade-row embedded within multi-stage turbomachines is dominated by such highly unsteady fluid flow conditions. The production of wakes and circumferential pressure variations from adjacent blade-rows causes large unsteady energy transfers between the fluid and the blades. Determination of the forced response of a blade requires the ability to predict the unsteady loads which are induced by these aerodynamic sources. A review of research publications was done to determine recent investigations of the response of turbomachinery blading subjected to aerodynamic excitations. Such excitations are a direct result of the blade-row aerodynamic interaction which occurs between adjacent cascades of blades. The reports and papers reviewed have been organized into areas emphasizing experimental or analytical efforts.

  4. [Comparative study of the repair of full thickness tear of the supraspinatus by means of "single row" or "suture bridge" techniques].

    PubMed

    Arroyo-Hernández, M; Mellado-Romero, M A; Páramo-Díaz, P; Martín-López, C M; Cano-Egea, J M; Vilá Y Rico, J

    2015-01-01

    The purpose of this study is to analyze if there is any difference between the arthroscopic reparation of full-thickness supraspinatus tears with simple row technique versus suture bridge technique. We accomplished a retrospective study of 123 patients with full-thickness supraspinatus tears between January 2009 and January 2013 in our hospital. There were 60 simple row reparations, and 63 suture bridge ones. The mean age in the simple row group was 62.9, and in the suture bridge group was 63.3 years old. There were more women than men in both groups (67%). All patients were studied using the Constant test. The mean Constant test in the suture bridge group was 76.7, and in the simple row group was 72.4. We have also accomplished a statistical analysis of each Constant item. Strength was higher in the suture bridge group, with a significant statistical difference (p 0.04). The range of movement was also greater in the suture bridge group, but was not statistically significant. Suture bridge technique has better clinical results than single row reparations, but the difference is not statistically significant (p = 0.298).

  5. An experimental investigation of turbomachine blade row aeromechanics

    NASA Astrophysics Data System (ADS)

    Feiereisen, John Michael

    This research was directed at understanding two major issues in turbomachine unsteady aerodynamics: (1) two-dimensional modeling of the unsteady aerodynamic excitation to a blade row within the constraints of linearized theory, and (2) the resulting unsteady aerodynamic loading of a blade row utilizing linearized theory analysis. These objectives were pursued by means of a series of experiments in the Purdue Annular Cascade Research Facility. This facility experimentally reproduces the fundamental unsteady flow phenomena inherent in axial flow turbomachines. The unsteady periodic flow field generated by rotating rows of perforated plates and airfoil cascades was measured with a two-component hot-wire anemometer and an unsteady total pressure probe and characterized in terms of the two-dimensional unsteady velocity and unsteady static pressure perturbations. The resulting unsteady periodic chordwise surface pressure distributions on a downstream stator row were measured with miniature high-frequency response pressure transducers mounted within the stator airfoils. Thus the unsteady aerodynamic excitation and resulting unsteady aerodynamic response were quantitatively ascertained. The periodic unsteady flow perturbations were analyzed as superpositions of harmonic vortical and potential flow perturbations, with each of these fundamental perturbations modeled as a spatial flow nonuniformity which is temporally steady in an appropriately rotating reference frame. The unsteady velocity associated with an harmonic vortical perturbation was shown to be parallel to the mean velocity vector in the rotating relative reference frame. The unsteady potential perturbations were shown to either propagate or decay axially depending upon flow conditions, with the propagation or decay determined by the mean relative Mach number in the rotating reference frame. Unsteady flow fields generated by rotating rows of perforated plates were found to be almost purely vortical perturbations

  6. Improving the efficiency of isolated microspore culture in six-row spring barley: II-exploring novel growth regulators to maximize embryogenesis and reduce albinism.

    PubMed

    Esteves, Patricio; Clermont, Isabelle; Marchand, Suzanne; Belzile, François

    2014-06-01

    Two alternative cytokinins, thidiazuron and meta-topoline, were tested in isolated microspore culture on recalcitrant barley genotypes (six-row, spring), and green plant regeneration was improved substantially. Doubled-haploid (DH) plants are coveted in plant breeding and in genetic studies, since they are rapidly obtained and perfectly homozygous. In barley, DHs are produced mainly via androgenesis, and isolated microspore culture (IMC) constitutes the method offering the greatest potential efficiency. However, IMC can often be challenging in some genotypes because of low yield of microspores, low regeneration and high incidence of albinism. Six-row spring-type barleys, the predominant type grown in Eastern Canada, are considered recalcitrant in this regard. Our general objective was to optimize an IMC protocol for DH production in six-row spring barley. In particular, we explored the use of alternative hormones in the induction medium (thidiazuron and dicamba), and in the regeneration medium (meta-topoline). This optimization was performed on two typical six-row spring (ACCA and Léger), a two-row spring (Gobernadora) and a two-row winter (Igri) barley cultivar. When 6-benzyl-aminopurine (BAP) was replaced by a combination of thidiazuron and dicamba in the induction medium, a 5.1-fold increase (P < 0.01) in the production of green plants resulted. This increase was mainly achieved by a reduction of albinism. Moreover, a 2.9-fold increase (P < 0.01) in embryo differentiation into green plants was obtained using meta-topoline instead of BAP in the regeneration medium. Together, these innovations allowed us to achieve a substantial improvement in the efficiency of IMC in this recalcitrant type of barley. These results were later successfully validated using sets of F1s from a six-row spring barley breeding program.

  7. Eccentric Ergometer Training Promotes Locomotor Muscle Strength but Not Mitochondrial Adaptation in Patients with Severe Chronic Obstructive Pulmonary Disease

    PubMed Central

    MacMillan, Norah J.; Kapchinsky, Sophia; Konokhova, Yana; Gouspillou, Gilles; de Sousa Sena, Riany; Jagoe, R Thomas; Baril, Jacinthe; Carver, Tamara E.; Andersen, Ross E.; Richard, Ruddy; Perrault, Hélène; Bourbeau, Jean; Hepple, Russell T.; Taivassalo, Tanja

    2017-01-01

    Eccentric ergometer training (EET) is increasingly being proposed as a therapeutic strategy to improve skeletal muscle strength in various cardiorespiratory diseases, due to the principle that lengthening muscle actions lead to high force-generating capacity at low cardiopulmonary load. One clinical population that may particularly benefit from this strategy is chronic obstructive pulmonary disease (COPD), as ventilatory constraints and locomotor muscle dysfunction often limit efficacy of conventional exercise rehabilitation in patients with severe disease. While the feasibility of EET for COPD has been established, the nature and extent of adaptation within COPD muscle is unknown. The aim of this study was therefore to characterize the locomotor muscle adaptations to EET in patients with severe COPD, and compare them with adaptations gained through conventional concentric ergometer training (CET). Male patients were randomized to either EET (n = 8) or CET (n = 7) for 10 weeks and matched for heart rate intensity. EET patients trained on average at a workload that was three times that of CET, at a lower perception of leg fatigue and dyspnea. EET led to increases in isometric peak strength and relative thigh mass (p < 0.01) whereas CET had no such effect. However, EET did not result in fiber hypertrophy, as morphometric analysis of muscle biopsies showed no increase in mean fiber cross-sectional area (p = 0.82), with variability in the direction and magnitude of fiber-type responses (20% increase in Type 1, p = 0.18; 4% decrease in Type 2a, p = 0.37) compared to CET (26% increase in Type 1, p = 0.04; 15% increase in Type 2a, p = 0.09). EET had no impact on mitochondrial adaptation, as revealed by lack of change in markers of mitochondrial biogenesis, content and respiration, which contrasted to improvements (p < 0.05) within CET muscle. While future study is needed to more definitively determine the effects of EET on fiber hypertrophy and associated underlying

  8. Eccentric Ergometer Training Promotes Locomotor Muscle Strength but Not Mitochondrial Adaptation in Patients with Severe Chronic Obstructive Pulmonary Disease.

    PubMed

    MacMillan, Norah J; Kapchinsky, Sophia; Konokhova, Yana; Gouspillou, Gilles; de Sousa Sena, Riany; Jagoe, R Thomas; Baril, Jacinthe; Carver, Tamara E; Andersen, Ross E; Richard, Ruddy; Perrault, Hélène; Bourbeau, Jean; Hepple, Russell T; Taivassalo, Tanja

    2017-01-01

    Eccentric ergometer training (EET) is increasingly being proposed as a therapeutic strategy to improve skeletal muscle strength in various cardiorespiratory diseases, due to the principle that lengthening muscle actions lead to high force-generating capacity at low cardiopulmonary load. One clinical population that may particularly benefit from this strategy is chronic obstructive pulmonary disease (COPD), as ventilatory constraints and locomotor muscle dysfunction often limit efficacy of conventional exercise rehabilitation in patients with severe disease. While the feasibility of EET for COPD has been established, the nature and extent of adaptation within COPD muscle is unknown. The aim of this study was therefore to characterize the locomotor muscle adaptations to EET in patients with severe COPD, and compare them with adaptations gained through conventional concentric ergometer training (CET). Male patients were randomized to either EET (n = 8) or CET (n = 7) for 10 weeks and matched for heart rate intensity. EET patients trained on average at a workload that was three times that of CET, at a lower perception of leg fatigue and dyspnea. EET led to increases in isometric peak strength and relative thigh mass (p < 0.01) whereas CET had no such effect. However, EET did not result in fiber hypertrophy, as morphometric analysis of muscle biopsies showed no increase in mean fiber cross-sectional area (p = 0.82), with variability in the direction and magnitude of fiber-type responses (20% increase in Type 1, p = 0.18; 4% decrease in Type 2a, p = 0.37) compared to CET (26% increase in Type 1, p = 0.04; 15% increase in Type 2a, p = 0.09). EET had no impact on mitochondrial adaptation, as revealed by lack of change in markers of mitochondrial biogenesis, content and respiration, which contrasted to improvements (p < 0.05) within CET muscle. While future study is needed to more definitively determine the effects of EET on fiber hypertrophy and associated underlying

  9. Effects of row-type, row-spacing, seeding rate, soil-type, and cultivar differences on soybean seed nutrition under US Mississippi Delta conditions

    USDA-ARS?s Scientific Manuscript database

    Management practices such as seeding rate (SR), planting date (PD), and row-type (RT: single- and twin-rows) may alter seed nutrition in soybean. The objective of this research was to investigate the effects of SR and PD on soybean seed composition (protein, oil, fatty acids, and sugars) and mineral...

  10. A new proposal to guide velocity and inclination in the ramp protocol for the treadmill ergometer.

    PubMed

    Barbosa e Silva, Odwaldo; Sobral Filho, Dário C

    2003-07-01

    To suggest criteria to guide protocol prescription in ramp treadmill testing, according to sex and age, based on velocity, inclination, and max VO2 reached by the population studied. Prospective study describing heart rate (HR), time, velocity, inclination, and VO2 estimated at maximum effort of 1840 individuals from 4 to 79 years old, who performed a treadmill test (TT) according to the ramp protocol. A paired Student t test was used to assess the difference between predicted and reached max VO2, calculated according to the formulas of the "American College of Sports Medicine". Submaximal HR was surpassed in 90.1% of the examinations, with a mean time of 10.0 2.0 minute. Initial and peak inclination velocity of the exercise and max VO2 were inversely proportional to age and were greater in male patients. Predicted Max VO2 was significantly lower than that reached in all patients, except for female children and adolescents (age < 20 years old). Use of velocity, inclination, and maximum VO2 actually reached, as a criterion in prescribing the ramp protocol may help in the performance of exercise in treadmill testing. The ramp protocol was well accepted in all age groups and sexes with exercise time within the programmed 8 to 12 minutes.

  11. A biomechanical comparison of tendon-bone interface motion and cyclic loading between single-row, triple-loaded cuff repairs and double-row, suture-tape cuff repairs using biocomposite anchors.

    PubMed

    Barber, F Alan; Drew, Otis R

    2012-09-01

    To compare tendon-bone interface motion and cyclic loading in a single-row, triple-loaded anchor repair with a suture-tape, rip-stop, double-row rotator cuff repair. Using 18 human shoulders from 9 matched cadaveric pairs, we created 2 groups of rotator cuff repairs. Group 1 was a double-row, rip-stop, suture-tape construct. Group 2 was a single-row, triple-loaded construct. Before mechanical testing, the supraspinatus footprint was measured with calipers. A superiorly positioned digital camera optically measured the tendon footprint motion during 60° of humeral internal and external rotation. Specimens were secured at a fixed angle not exceeding 45° in reference to the load. After preloading, each sample was cycled between 10 N and 100 N for 200 cycles at 1 Hz, followed by destructive testing at 33 mm/s. A digital camera with tracking software measured the repair displacement at 100 and 200 cycles. Ultimate load and failure mode for each sample were recorded. The exposed anterior footprint border (6.5% ± 6%) and posterior footprint border (0.9% ± 1.7%) in group 1 were statistically less than the exposed anterior footprint border (30.3% ± 17%) and posterior footprint border (29.8% ± 14%) in group 2 (P = .003 and P < .001, respectively). The maximal internal rotation and external rotation tendon footprint displacements in group 1 (1.6 mm and 1.4 mm, respectively) were less than those in group 2 (both 3.6 mm) (P = .007 and P = .004, respectively). Mean displacement after 100 cycles for group 1 and group 2 was 2.0 mm and 3.2 mm, respectively, and at 200 cycles, mean displacement was 2.5 mm and 4.2 mm, respectively (P = .02). The mean ultimate failure load in group 1 (586 N) was greater than that in group 2 (393 N) (P = .02). The suture-tendon interface was the site of most construct failures. The suture-tape, rip-stop, double-row rotator cuff repair had greater footprint coverage, less rotational footprint displacement, and a greater mean ultimate failure load

  12. Functional results after proximal row carpectomy to salvage a wrist.

    PubMed

    Kremer, Thomas; Sauerbier, Michael; Trankle, Markus; Dragu, Adrian; Germann, Guenter; Baumeister, Steffen

    2008-01-01

    Proximal row carpectomy is a movement-preserving procedure in the treatment of arthrosis of the wrist. We have retrospectively assessed the objective and subjective functional results after proximal row carpectomy. Assessment of outcome included measurement of range of movement (ROM), grip strength and self-assessment of pain relief with a visual analogue scale (VAS) and the Disabilities of arm, shoulder, and hand (DASH) questionnaire. Results were graded using the Mayo and Krimmer wrist scores. Fourty-five patients (mean age 48 (30-67) years) were evaluated with a follow-up of 32 (8-115) months. Underlying conditions included: degenerative arthritis secondary to scapholunate advanced collapse deformity, or chronic scaphoid non-union (n=35), Kienbock disease stage III (n=4), chronic perilunate dislocation and fracture-dislocation (n=4), avascular necrosis of the scaphoid (n=1), and severe radiocarpal arthrosis secondary to distal radial fracture (n=1). Active ROM for wrist extension and flexion was 70 degrees and mean radial and ulnar deviation 30.8 degrees . Grip strength was 51% of the unaffected side. The average DASH score was 26. The intensity of the pain, measured by VAS, was reduced by 44% after strenuous activities and by 71% at rest. The Mayo and Krimmer wrist scores were 55 and 62 points indicating good results; 32 patients returned to work and 25 patients to their former occupation. Our results show that proximal row carpectomy is a technically easy operation that preserves a satisfying ROM and pain relief, and is recommended when the head of the capitate and the lunate fossa are not affected by arthrosis.

  13. The Energetic Assessment of Frictional Instability Based on Rowe's Theory

    NASA Astrophysics Data System (ADS)

    Hirata, M.; Muto, J.; Nagahama, H.

    2015-12-01

    Frictional instability that controls the occurrence of unstable slips has been related to (1) rate and state dependent friction law (Dieterich, 1979; Ruina, 1983) and (2) shear localization in a gouge layer (e.g., Byerlee et al., 1978; Logan et al., 1979). Ikari et al. (2011) indicated that the transitions of frictional parameters obtained from the rate and state dependent friction law involve shear localization. However, the underlining theoretical background for their link has been unknown. Therefore, in this study, we investigate their relation theoretically and experimentally based on Rowe's theory on constant minimum energy ratio (Rowe, 1962) describing particle deformations quantitatively by energetic analysis. In theoretical analysis using analytical dynamics and irreversible thermodynamics, the energetic criterion about frictional instability is obtained; unstable slip occurs at energy ratios below 1. In friction experiments using a gas medium apparatus, simulated fault gouge deforms obeying the Rowe's theory. Additionally, the energy ratios change gradually with shear and show below 1 before the occurrence of unstable slip. Moreover, energy ratios are derived from volume changes. Transition of energy ratios from increase to decrease, which has been confirmed at the end of compaction, indicates the onset of volume increase toward the occurrence of unstable slip. The volume increases likely correspond to the formation of R1-shears with open mode character, which occurs prior to the unstable slip. Shear localization leads to a change in internal friction angle which is a statistical parameter to constitute a energy ratio. In short, changes in internal friction angle play an important role in evolving from being frictionally stable to unstable. From these results, the physical and energetic background for their link between the frictional parameter and shear localization becomes clear.

  14. Film cooling: case of double rows of staggered jets.

    PubMed

    Dorignac, E; Vullierme, J J; Noirault, P; Foucault, E; Bousgarbiès, J L

    2001-05-01

    An experimental investigation of film cooling of a wall in a case of double rows of staggered hot jets (65 degrees C) in an ambient air flow. The wall is heated at a temperature value between the one of the jets and the one of the main flow. Experiments have been carried out for different injection rates, the main flow velocity is maintained at 32 m/s. Association of the measures of temperature profiles by cold wire and the measures of wall temperature by infrared thermography allows us to describe the behaviour of the flows and to propose the best injection which assures a good cooling of the plate.

  15. 9. Detail view of columns on first floor. This row ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Detail view of columns on first floor. This row of columns indicates the former location of the exterior mill wall before World War II era expansion. The unusual column and beam connection was a key part of the mill structural system patented by Providence, Rhode Island engineers Charles Praray and Charles Makepeace in 1894. Each column was originally located in the apex of triangular window bay, but not connected to the exterior wall. Modifications on the right side of each column support the beams of the addition. - Dixie Cotton Mill, 710 Greenville Street, La Grange, Troup County, GA

  16. Plant, soil, and shadow reflectance components of row crops

    NASA Technical Reports Server (NTRS)

    Richardson, A. J.; Wiegand, C. L.; Gausman, H. W.; Cuellar, J. A.; Gerbermann, A. H.

    1975-01-01

    Data from the first Earth Resource Technology Satellite (LANDSAT-1) multispectral scanner (MSS) were used to develop three plant canopy models (Kubelka-Munk (K-M), regression, and combined K-M and regression models) for extracting plant, soil, and shadow reflectance components of cropped fields. The combined model gave the best correlation between MSS data and ground truth, by accounting for essentially all of the reflectance of plants, soil, and shadow between crop rows. The principles presented can be used to better forecast crop yield and to estimate acreage.

  17. Plant, soil, and shadow reflectance components of row crops

    NASA Technical Reports Server (NTRS)

    Richardson, A. J.; Wiegand, C. L.; Gausman, H. W.; Cuellar, J. A.; Gerbermann, A. H.

    1975-01-01

    Data from the first Earth Resource Technology Satellite (LANDSAT-1) multispectral scanner (MSS) were used to develop three plant canopy models (Kubelka-Munk (K-M), regression, and combined K-M and regression models) for extracting plant, soil, and shadow reflectance components of cropped fields. The combined model gave the best correlation between MSS data and ground truth, by accounting for essentially all of the reflectance of plants, soil, and shadow between crop rows. The principles presented can be used to better forecast crop yield and to estimate acreage.

  18. Diagnostic Imaging of Pulmonary Thromboembolism by Multidetector-row CT

    PubMed Central

    2010-01-01

    For diagnosis of pulmonary thromboembolism, multidetector-row computed tomography (CT) is a minimally invasive imaging technique that can be performed rapidly with high sensitivity and specificity, and has been increasingly employed as the imaging modality of first choice for this disease. Since deep vein thrombosis in the legs, which is important as a thrombus source, can be evaluated immediately after the diagnosis of pulmonary thromboembolism, this diagnostic method is considered to provide important information when deciding on a comprehensive therapeutic strategy for this disease. PMID:23555409

  19. Two-source energy balance model to calculate row crop E.T. and ET:Advances at ARS, Bushland, TX 2010-2015

    USDA-ARS?s Scientific Manuscript database

    The two-source energy balance (TSEB) model has undergone several advances recently that improved its accuracy in calculating evaporation (E), transpiration (T), and evapotranspiration (ET) for row crops. These advances were tested using microlysimeter, sap flow, and large weighing lysimeter measurem...

  20. An experimental investigation of the generation and consequences of acoustic waves in an axial-flow compressor - The effect of variations in the axial spacing between blade rows

    NASA Astrophysics Data System (ADS)

    Parker, R.; Stoneman, S. A. T.

    1987-08-01

    The excitation of acoustic resonances in axial-flow compressors was investigated experimentally on a low speed, single stage test rig. It was found that the axial spacing between blade rows had a marked effect on the acoustic amplitudes and on the speeds at which the various resonances were excited. A simple model which is consistent with the experimental results is proposed.

  1. Risk evaluation to fish ponds of drift from common aerially-applied herbicides to five major row crops of the delta

    USDA-ARS?s Scientific Manuscript database

    Row crop herbicides were tested for possible adverse effects on fish production pond plankton and water quality in triplicate 500-L outdoor, pool mesocosms. Treatments were drift at low (1% of full field rates) and high levels (10% of the full rate) to production ponds of 5 ha and larger, and no dri...

  2. Can Row Spacing Influence Arthropod Communities in Soybean? Implications for Early and Late Planting.

    PubMed

    Buchanan, Amanda L; Zobel, Emily; Hinds, Jermaine; Rosario-Lebron, Armando; Hooks, Cerruti R R

    2015-06-01

    Row spacing in agricultural systems can influence crop yield as well as pest and predator abundances. Soybean (Glycine max L. Merrill) growers in Maryland typically plant in narrow (∼19 cm), medium (∼38 cm), or wide (∼76 cm)-spaced rows, and there is a general lack of information on how these row-spacing schemes influence arthropod abundance and soybean yields. A study was conducted during two growing seasons to determine the effect of soybean row spacing and planting date (early and late) on soybean arthropods and yield. Despite a great deal of variation in arthropod responses to row spacing, and interactions between row spacing and study year, leaf-feeding herbivores were generally more abundant in narrow-spaced soybeans. All arthropod functional groups were more abundant, and yield was greater in early-planted soybeans relative to late-planted soybeans. Potential causes and implications of these finding are discussed.

  3. Validity of submaximal exercise testing in adults with athetospastic cerebral palsy.

    PubMed

    Satonaka, Ayako; Suzuki, Nobuharu; Kawamura, Morio

    2012-03-01

    To examine the validity of the multistage submaximal cycle ergometer test for adults with athetospastic cerebral palsy. Cross-sectional and correlative study. Oxygen uptake and heart rates were recorded while the participants underwent the maximal cycle ergometer test and the multistage submaximal cycle ergometer test. Peak oxygen consumption (Vo(2)peak) was achieved by the maximal cycle test. Maximum oxygen consumption (VO(2)max) was predicted by the multistage submaximal cycle ergometer test. Research laboratory setting. Adults with athetospastic cerebral palsy (N=16; 10 women and 6 men; mean age ± SD, 43.7±14.5y). Not applicable. Peak VO(2) was compared with the predicted VO(2)max. Mean VO(2)peak and the predicted VO(2)max ± SD were 866.9±202.9 mL/min(-1) and 857.4±248.4 mL/min(-1), respectively. There was not a significant difference between VO(2)peak values and the predicted VO(2)max values (r=.28). And there was a significant correlation between VO(2)peak values and the predicted VO(2)max values (r=.94, P<.001). SE of the estimate (or SE for X to Y) was 71.2 mL/min(-1), equivalent to 7.4%. The multistage submaximal cycle ergometer test may provide a valid VO(2)max estimate of adults with athetospastic cerebral palsy. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  4. Development of Magnetorheological Resistive Exercise Device for Rowing Machine

    PubMed Central

    Žiliukas, Pranas

    2016-01-01

    Training equipment used by professional sportsmen has a great impact on their sport performance. Most universal exercisers may help only to improve the general physical condition due to the specific kinematics and peculiar resistance generated by their loading units. Training of effective techniques and learning of psychomotor skills are possible only when exercisers conform to the movements and resistance typical for particular sports kinematically and dynamically. Methodology of developing a magnetorheological resistive exercise device for generating the desired law of passive resistance force and its application in a lever-type rowing machine are described in the paper. The structural parameters of a controllable hydraulic cylinder type device were found by means of the computational fluid dynamics simulation performed by ANSYS CFX software. Parameters describing the magnetorheological fluid as non-Newtonian were determined by combining numerical and experimental research of the resistance force generated by the original magnetorheological damper. A structural scheme of the device control system was developed and the variation of the strength of magnetic field that affects the magnetorheological fluid circulating in the device was determined, ensuring a variation of the resistance force on the oar handle adequate for the resistance that occurs during a real boat rowing stroke. PMID:27293479

  5. Development of Magnetorheological Resistive Exercise Device for Rowing Machine.

    PubMed

    Grigas, Vytautas; Šulginas, Anatolijus; Žiliukas, Pranas

    2015-01-01

    Training equipment used by professional sportsmen has a great impact on their sport performance. Most universal exercisers may help only to improve the general physical condition due to the specific kinematics and peculiar resistance generated by their loading units. Training of effective techniques and learning of psychomotor skills are possible only when exercisers conform to the movements and resistance typical for particular sports kinematically and dynamically. Methodology of developing a magnetorheological resistive exercise device for generating the desired law of passive resistance force and its application in a lever-type rowing machine are described in the paper. The structural parameters of a controllable hydraulic cylinder type device were found by means of the computational fluid dynamics simulation performed by ANSYS CFX software. Parameters describing the magnetorheological fluid as non-Newtonian were determined by combining numerical and experimental research of the resistance force generated by the original magnetorheological damper. A structural scheme of the device control system was developed and the variation of the strength of magnetic field that affects the magnetorheological fluid circulating in the device was determined, ensuring a variation of the resistance force on the oar handle adequate for the resistance that occurs during a real boat rowing stroke.

  6. Women's religious conversions on death row: theorizing religion and state.

    PubMed

    Cooey, P M

    2002-01-01

    Most scholars of religion who approach the phenomena associated with religious conversion in order to theorize religion tend to ignore the legal and political implications of the actual context in which conversion occurs for theorizing religion itself. Meanwhile, political and legal theorists who attend to the implications of executing convicted murderers who undergo religious conversion on death row err in a different direction. They virtually ignore the significance of the claims made by the converts and their associates about the conversion themselves for theorizing the state. Scholars across disciplines increasingly address issues of race, class, gender, and sexual orientation in respect to theorizing religion and theorizing the state independently of one another. At the same time, they do not seize the opportunity to incorporate their analyses into a wider study of the sociocultural production of religion and state in relation to each other. I examine the religious conversion of Karla Faye Tucker and Wanda Jean Allen on death row, as well as the scholarship that their convictions, conversions, and executions have generated across academic disciplines and fields. Close examination illustrates well the necessity for theorizing religion and the state in relation to one another in order to understand either adequately.

  7. Directional reflectance factor distributions of a cotton row crop

    NASA Technical Reports Server (NTRS)

    Kimes, D. S.; Newcomb, W. W.; Schutt, J. B.; Pinter, P. J., Jr.; Jackson, R. D.

    1984-01-01

    The directional reflectance factor distribution spanning the entire exitance hemisphere was measured for a cotton row crop (Gossypium barbadense L.) with 39 percent ground cover. Spectral directional radiances were taken in NOAA satellite 7 AVHRR bands 1 and 2 using a three-band radiometer with restricted 12 deg full angle field of view at half peak power points. Polar co-ordinate system plots of directional reflectance factor distributions and three-dimensional computer graphic plots of scattered flux were used to study the dynamics of the directional reflectance factor distribution as a function of spectral band, geometric structure of the scene, solar zenith and azimuth angles, and optical properties of the leaves and soil. The factor distribution of the incomplete row crops was highly polymodal relative to that for complete vegetation canopies. Besides the enhanced reflectance for the antisolar point, a reflectance minimum was observed towards the forwardscatter direction in the principle plane of the sun. Knowledge of the mechanics of the observed dynamics of the data may be used to provide rigorous validation for two- or three-dimensional radiative transfer models, and is important in interpreting aircraft and satellite data where the solar angle varies widely.

  8. Complete inclusion of adaptive rowing only 1000 m ahead.

    PubMed

    Smoljanovic, Tomislav; Bojanic, Ivan; Hannafin, Jo A; Urhausen, Axel; Theisen, Daniel; Seil, Romain; Lacoste, Alain

    2013-09-01

    Adaptive rowing (AR) at the Paralympic level is accessible for rowers with physical disability. AR was included for the first time in the Beijing 2008 Paralympic Games. Racing distance for all AR events is currently 1000 m, which impedes public recognition of this sport and leads to many organisational challenges during the inclusive World Rowing Championships. The aim of this report was to discuss the feasibility of increasing AR race distance to 2000 m from a sports injury and athletic health perspective. As limited data on injury and illness risks exist in AR, knowledge and experiences had to be taken from other Paralympic sports. The anticipated duration of 2000 m AR competitions is either comparable or considerably lower than that of the other Paralympic disciplines with similar characteristics. AR has inherent injury and health risks especially within thorax, shoulders and low back region, but they are not expected to be significantly modified by increased racing times. Specific considerations need to be taken into account for athletes with a spinal cord injury, like in other sport disciplines. There are no distinctive contra-indications for AR events of 2000 m based on the current literature review and a 10-year experience in this sport. Long-term follow-ups are needed to understand fully the injury and health risk associated with AR and to develop appropriate prevention strategies.

  9. [RESEARCH PROGRESS OF BIOMECHANICS OF PROXIMAL ROW CARPAL INSTABILITY].

    PubMed

    Guo, Jinhai; Huang, Fuguo

    2015-01-01

    To review the research progress of the biomechanics of proximal row carpal instability (IPRC). The related literature concerning IPRC was extensively reviewed. The biomechanical mechanism of the surrounding soft tissue in maintaining the stability of the proximal row carpal (PRC) was analyzed, and the methods to repair or reconstruct the stability and function of the PRC were summarized from two aspects including basic biomechanics and clinical biomechanics. The muscles and ligaments of the PRC are critical to its stability. Most scholars have reached a consensus about biomechanical mechanism of the PRC, but there are still controversial conclusions on the biomechanics mechanism of the surrounding soft tissue to stability of distal radioulnar joint when the triangular fibrocartilage complex are damaged and the biomechanics mechanism of the scapholunate ligament. At present, there is no unified standard about the methods to repair or reconstruct the stability and function of the PRC. So, it is difficult for clinical practice. Some strides have been made in the basic biomechanical study on muscle and ligament and clinical biomechanical study on the methods to repair or reconstruct the stability and function of PRC, but it will be needed to further study the morphology of carpal articular surface and the adjacent articular surface, the pressure of distal carpals to proximal carpal and so on.

  10. Yankee Rowe isotopics benchmark using MCNP-XT

    SciTech Connect

    Xu, Z.; Whitmer, C.

    2013-07-01

    The Yankee Rowe spent fuel isotopic data provides a valuable source to benchmark the burnup calculations as part of verification and validation (V and V) efforts for the TerraPower's Monte Carlo depletion code, MCNP-XT. A total of 71 fuel rods were selected in the Yankee Rowe isotopic measurements covering a burnup range up to 44 MWd/kg ({approx}4.4%) under both the asymptotic spectrum and the non-asymptotic spectrum. The MCNP-XT pin cell depletion provides a comparison against the asymptotic spectrum measurement; and full assembly depletion with 322 depletion materials provides comparisons against various non-asymptotic depletion conditions. All calculations are performed based on the recent ENDF/B-VII.O data. Furthermore, the Monte Carlo depletion uncertainties and biases were examined showing their effect as insignificant. The set of burnup calculations cover the scattered experimental measurements demonstrating excellent agreement with the measured values. This benchmark exercise demonstrates the depletion analysis capability of the MCNP-XT code and validates the low burnup range. (authors)

  11. Recent technologic advances in multi-detector row cardiac CT.

    PubMed

    Halliburton, Sandra Simon

    2009-11-01

    Recent technical advances in multi-detector row CT have resulted in lower radiation dose, improved temporal and spatial resolution, decreased scan time, and improved tissue differentiation. Lower radiation doses have resulted from the use of pre-patient z collimators, the availability of thin-slice axial data acquisition, the increased efficiency of ECG-based tube current modulation, and the implementation of iterative reconstruction algorithms. Faster gantry rotation and the simultaneous use of two x-ray sources have led to improvements in temporal resolution, and gains in spatial resolution have been achieved through application of the flying x-ray focal-spot technique in the z-direction. Shorter scan times have resulted from the design of detector arrays with increasing numbers of detector rows and through the simultaneous use of two x-ray sources to allow higher helical pitch. Some improvement in tissue differentiation has been achieved with dual energy CT. This article discusses these recent technical advances in detail.

  12. Comparison of the Clinical and Radiological Oucomes of Conventional Double row and Double row Suture Bridge Repairs in Rotator Cuff Tears

    PubMed Central

    Muiño, José María Silberberg; Gimenez, Martín Alejandro; Salvucci, Mauro Gabriel Maroa; Ferro, Diego; Rullan, Ramón Muiña; Blanchero, Pablo

    2017-01-01

    Objectives: To compare clinical and radiological results of two types of rotator cuff (RC) repairs: the double row and double row-suture bridge. Methods: Forty-two patients with a complete tear (medium and large size) of the RC were repaired by a double row arthroscopic technique. Minimum follow-up was 19 months (range, 19-28 months). Clinical outcomes were assessed by the Modified Constant Scale and satisfaction rate by an independent observer; VAS, UCLA and ASES. Radiological results were assed by a postoperative MRI by a musculoskeletal radiologist. Results: Series of 22 patients in the double row technique (Group A) and 20 patients in the double-row suture bridge (Gruop B). Statistically there was a significant improvement in the Constant Scale, satisfaction rate, muscle assessment, VAS, UCLA and ASES in both groups after the surgical procedure. There were no significant clinical differences between both groups at any time after the surgical procedure. According to MRI postop, 19/22 shoulders in Group A and 18/20 in Group B remained intact, with no significant differences between the two groups. Conclusion: RC repairs with double row and double-row-suture bridge techniques provide clinical and radiological good and excelent results. In our retrospective, mid-size study, we have found no differences between these two repair techniques.

  13. Multiphase contrast-saline mixture injection with dual-flow in 64-row MDCT coronary CTA.

    PubMed

    Cao, Lizhen; Du, Xiangying; Li, Pengyu; Liu, Yaou; Li, Kuncheng

    2009-03-01

    To explore the feasibility of multiphase contrast-saline mixture with dual-flow injection technique for visualization of right ventricular (RV) cavity and interventricular septum (IVS) in 64-row multidetector computed tomography (MDCT) coronary angiography. Twenty-four patients underwent coronary CT angiography (CTA) imaging with 64-row MDCT. In twelve patients (group A), 60 ml contrast medium (CM) bolus was followed by 40 ml saline, and in the other twelve patients (group B), 50 ml CM bolus was followed by 50 ml contrast-saline mixture at 60:40 ratio. The CM, saline and contrast-saline mixture flow rate were all 5.0 ml/s. Two experienced radiologists measured the CT values of ascending aorta, descending aorta, pulmonary artery and RV, rated the uniformity of RV cavity, the visualization of coronary arteries and IVS independently. By Kappa test, agreement between the two radiologists was 0.93 and 0.86 concerning the CT value measurements and the grades of the three indexes, respectively. By t-test, the mean CT values of ascending aorta and descending aorta of the two groups had no statistical difference (t=1.459, P>0.05; t=1.619, P>0.05); while the mean CT values of pulmonary artery and RV cavity had statistical differences (t=8.316, P<0.05; t=10.372, P<0.05). By two-related rank sum test, according to the visualization of coronary arteries and the uniformity of RV cavity, there were no statistical differences (U=66.00, P>0.05; U=54.00, P>0.05); while according to the visualization of IVS, group B was better than group A (U=8.00, P<0.05). In coronary CTA, a contrast-saline mixture after CM bolus can provide clear visualization of RV and IVS and LV without impairing coronary CTA image.

  14. Screening for carotid injury in trauma patients: image quality of 16-detector-row computed tomography angiography.

    PubMed

    Borisch, I; Boehme, T; Butz, B; Hamer, O W; Feuerbach, S; Zorger, N

    2007-09-01

    The introduction of multidetector-row computed tomography (MDCT) has revolutionized the initial management of multiply injured patients. This technology has the potential to improve the imaging of traumatic vascular injuries. To evaluate the quality of multidetector-row computed tomography angiography (MDCTA) of the carotid arteries in the setting of a routine whole-body trauma scan. 87 trauma patients underwent a routine whole-body CT scan in a 16-detector-row scanner including an MDCTA with a reconstructed axial slice thickness of 3 mm. Images were reviewed by three experienced radiologists with emphasis on image quality. Contrast density, severity, and origin of artifacts and the occurrence of vessel lesions were assessed for different vessel segments. 3642 separate vessel segments were evaluated. Contrast density was rated good or sufficient for diagnosis in 99.8%. A total of 67.3% of vessel segments were free of artifacts, while 27.9% of vessel segments showed minor artifacts not impairing diagnostic evaluation. Clinically relevant artifacts obscuring a vessel segment occurred in 4.7% and were mostly caused by dental hardware. Four dissections of the internal carotid artery were diagnosed by all three radiologists. As a rapid screening test for blunt carotid artery injury, integration of MDCTA in the routine imaging workup of trauma patients utilizing a whole-body CT trauma scan is possible and practicable. Image quality is mostly sufficient for diagnosis, but impaired in a few cases by artifacts deriving primarily from dental hardware.

  15. 7 CFR 718.108 - Measuring acreage including skip row acreage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE FARM MARKETING QUOTAS, ACREAGE ALLOTMENTS, AND PRODUCTION ADJUSTMENT PROVISIONS... production planting techniques. (d) The Deputy Administrator has the discretionary authority to allow row...

  16. Mechanical and propelling efficiency in swimming derived from exercise using a laboratory-based whole-body swimming ergometer.

    PubMed

    Zamparo, Paola; Swaine, Ian L

    2012-08-15

    Determining the efficiency of a swimming stroke is difficult because different "efficiencies" can be computed based on the partitioning of mechanical power output (W) into its useful and nonuseful components, as well as because of the difficulties in measuring the forces that a swimmer can exert in water. In this paper, overall efficiency (η(O) = W(TOT)/Ė, where W(TOT) is total mechanical power output, and Ė is overall metabolic power input) was calculated in 10 swimmers by means of a laboratory-based whole-body swimming ergometer, whereas propelling efficiency (η(P) = W(D)/W(TOT), where W(D) is the power to overcome drag) was estimated based on these values and on values of drag efficiency (η(D) = W(D)/Ė): η(P) = η(D)/η(O). The values of η(D) reported in the literature range from 0.03 to 0.09 (based on data for passive and active drag, respectively). η(O) was 0.28 ± 0.01, and η(P) was estimated to range from ≈ 0.10 (η(D) = 0.03) to 0.35 (η(D) = 0.09). Even if there are obvious limitations to exact simulation of the whole swimming stroke within the laboratory, these calculations suggest that the data reported in the literature for η(O) are probably underestimated, because not all components of W(TOT) can be measured accurately in this environment. Similarly, our estimations of η(P) suggest that the data reported in the literature are probably overestimated.

  17. Heat Transfer, Adiabatic Effectiveness and Injectant Distributions Downstream of Single Rows and Two Staggered Rows of Film-Cooling Holes with Simple and Compound Angles

    DTIC Science & Technology

    1991-12-01

    ROWS AND TWO STAGGERED ROWS OF FILM-COOLING HOLES WITH SIMPLE AND COMPOUND ANGLES 92-01241 by DIII l, p111111~ 11I Stephen Mark Jackson DECEMBER 1991...HOLES WITH SIMPLE AND COMPOUND ANGLES 12. PERSONAL AUTHORS STEPHEN MARK JACKSON 13a TYPE OF REPORT 13b TIME COVERED 14. DATE OF REPORT (Year. A4int, Day...Rows of Film-Cooling Holes with Simple and Compound Angles by Stephen Mark Jackson lieutenant, United States Navy B.S., United States Naval Academy, 1983

  18. Acute appendicitis: comparison of low-dose and standard-dose unenhanced multi-detector row CT.

    PubMed

    Keyzer, Caroline; Tack, Denis; de Maertelaer, Viviane; Bohy, Pascale; Gevenois, Pierre Alain; Van Gansbeke, Daniel

    2004-07-01

    To prospectively compare low- and standard-dose unenhanced multi-detector row computed tomography (CT) in patients suspected of having acute appendicitis. Ninety-five consecutive patients underwent two unenhanced multi-detector row CT examinations with 4 x 2.5-mm collimation, 120 kVp, and 30 and 100 effective mAs. Two radiologists independently read the images obtained at each dose during two sessions. Readers recorded visualization of the appendix and presence of gas in its lumen, appendicolith, periappendiceal fat stranding, cecal wall thickening, and abscess or phlegmon to measure the diameter of the appendix and to propose diagnosis (appendicitis or alternative). Data were compared according to dose and reader, with definite diagnosis established on basis of surgical findings (n = 37) or clinical follow-up. chi(2) tests and logistic regression were used. Measurement agreements were assessed with Cohen kappa statistics. Twenty-nine patients had a definite diagnosis of appendicitis. No difference was observed between the frequency of visualization of the appendix (P =.874) neither in its mean diameter (P =.101-.696, according to readers and sessions) nor in the readers' overall diagnosis (P =.788) at each dose. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of each sign were not different between doses. Fat stranding, appendicolith, and diameter were the most predictive signs, regardless of dose, yielding approximately 90% of correct diagnoses. The ability to propose a correct alternative diagnosis was not influenced by the dose. Low-dose unenhanced multi-detector row CT has similar diagnostic performance as standard-dose unenhanced multi-detector row CT for the diagnosis of acute appendicitis. Copyright RSNA, 2004

  19. Proximal row carpectomy: minimum 20-year follow-up.

    PubMed

    Wall, Lindley B; Didonna, Michael L; Kiefhaber, Thomas R; Stern, Peter J

    2013-08-01

    Proximal row carpectomy (PRC) is a motion-sparing procedure for degenerative disorders of the proximal carpal row. Reported results at a minimum 10-year follow-up consistently show maintenance of strength, motion, and satisfaction with an average conversion rate to radiocarpal arthrodesis of 12%. We hypothesized that PRC would continue to provide a high level of satisfaction and function at a minimum of 20 years. Seventeen wrists in 16 patients, including 7 laborers, underwent PRC for symptomatic degenerative disorders of the proximal carpal row at an average age of 36 years. Patients returned for radiographic and clinical evaluation, and the Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) questionnaire and Patient-Related Wrist Evaluation were used for subjective assessment. Follow-up was a minimum of 20 years (average, 24 y). Eleven wrists (65%) underwent no further surgery at a minimum 20-year follow-up. The average time to failure of PRC, defined as the time from PRC to radiocarpal arthrodesis, was 11 years (range, 8 mo to 20 y). Ten of 11 patients who did not undergo radiocarpal arthrodesis continued to be satisfied, with minimal decrease in motion and grip strength compared with the uninvolved side. Average score for QuickDASH was 16 and for Patient-Related Wrist Evaluation was 26. The flexion-extension arc was 68°, and grip strength was 72% of the contralateral side. All patients returned to their original employment. There was no correlation between degenerative radiographic changes and satisfaction level. The predicted probability of failure revealed a higher risk in patients who underwent PRC at a younger age, which leveled off at age 40 years. PRC provides satisfaction at a minimum of 20 years with a survival rate of 65%. Whereas we recommend a minimum age for PRC between 35 and 40 years, young patients should not be excluded as PRC candidates; these patients should undergo appropriate preoperative counseling of their increased failure risk

  20. Multi-detector row CT of pancreatic islet cell tumors.

    PubMed

    Horton, Karen M; Hruban, Ralph H; Yeo, Charles; Fishman, Elliot K

    2006-01-01

    Pancreatic islet cell tumors (ICTs) are neuroendocrine neoplasms that produce and secrete hormones to a variable degree. These neoplasms can present a diagnostic challenge, both clinically and radiologically. ICTs can be classified as either syndromic or nonsyndromic on the basis of their clinical manifestations. Multi-detector row computed tomography (CT) plays an important role in the diagnosis and staging of both syndromic and nonsyndromic ICTs. In general, syndromic ICTs are less than 3 cm in size. They are typically hyperenhancing and are usually best seen on CT scans obtained during the arterial phase. Nonsyndromic ICTs tend to be larger than syndromic ICTs at presentation and are more likely to be cystic or necrotic. It is important for the radiologist to be familiar with appropriate CT protocol for the evaluation of patients with suspected pancreatic ICT and to understand the variable CT appearances of these neoplasms. (c) RSNA, 2006.

  1. Configuring bonds between first-row transition metals.

    PubMed

    Eisenhart, Reed J; Clouston, Laura J; Lu, Connie C

    2015-11-17

    Alfred Werner, who pioneered the field of coordination chemistry, envisioned coordination complexes as a single, transition metal atom at the epicenter of a vast ligand space. The idea that the locus of a coordination complex could be shared by multiple metals held together with covalent bonds would eventually lead to the discovery of the quadruple and quintuple bond, which have no analogues outside of the transition metal block. Metal-metal bonding can be classified into homometallic and heterometallic groups. Although the former is dominant, the latter is arguably more intriguing because of the inherently larger chemical space in which metal-metal bonding can be explored. In 2013, Lu and Thomas independently reported the isolation of heterometallic multiple bonds with exclusively first-row transition metals. Structural and theoretical data supported triply bonded Fe-Cr and Fe-V cores. This Account describes our continued efforts to configure bonds between first-row transition metals from titanium to copper. Double-decker ligands, or binucleating platforms that brace two transition metals in proximity, have enabled the modular synthesis of diverse metal-metal complexes. The resulting complexes are also ideal for investigating the effects of an "ancillary" metal on the properties and reactivities of an "active" metal center. A total of 38 bimetallic complexes have been compiled comprising 18 unique metal-metal pairings. Twenty-one of these bimetallics are strictly isostructural, allowing for a systematic comparison of metal-metal bonding. The nature of the chemical bond between first-row metals is remarkably variable and depends on two primary factors: the total d-electron count, and the metals' relative d-orbital energies. Showcasing the range of covalent bonding are a quintuply bonded (d-d)(10) Mn-Cr heterobimetallic and the singly bonded late-late pairings, e.g., Fe-Co, which adopt unusually high spin states. A long-term goal is to rationally tailor the

  2. Transfer of Complex Skill Learning from Virtual to Real Rowing

    PubMed Central

    Rauter, Georg; Sigrist, Roland; Koch, Claudio; Crivelli, Francesco; van Raai, Mark; Riener, Robert; Wolf, Peter

    2013-01-01

    Simulators are commonly used to train complex tasks. In particular, simulators are applied to train dangerous tasks, to save costs, and to investigate the impact of different factors on task performance. However, in most cases, the transfer of simulator training to the real task has not been investigated. Without a proof for successful skill transfer, simulators might not be helpful at all or even counter-productive for learning the real task. In this paper, the skill transfer of complex technical aspects trained on a scull rowing simulator to sculling on water was investigated. We assume if a simulator provides high fidelity rendering of the interactions with the environment even without augmented feedback, training on such a realistic simulator would allow similar skill gains as training in the real environment. These learned skills were expected to transfer to the real environment. Two groups of four recreational rowers participated. One group trained on water, the other group trained on a simulator. Within two weeks, both groups performed four training sessions with the same licensed rowing trainer. The development in performance was assessed by quantitative biomechanical performance measures and by a qualitative video evaluation of an independent, blinded trainer. In general, both groups could improve their performance on water. The used biomechanical measures seem to allow only a limited insight into the rowers' development, while the independent trainer could also rate the rowers' overall impression. The simulator quality and naturalism was confirmed by the participants in a questionnaire. In conclusion, realistic simulator training fostered skill gains to a similar extent as training in the real environment and enabled skill transfer to the real environment. In combination with augmented feedback, simulator training can be further exploited to foster motor learning even to a higher extent, which is subject to future work. PMID:24376518

  3. Proprioceptive isokinetic exercise test

    NASA Technical Reports Server (NTRS)

    Dempster, P. T.; Bernauer, E. M.; Bond, M.; Greenleaf, J. E.

    1993-01-01

    Proprioception, the reception of stimuli within the body that indicates position, is an important mechanism for optimal human performance. People exposed to prolonged bed rest, microgravity, or other deconditioning situations usually experience reduced proprioceptor and kinesthetic stimuli that compromise body balance, posture, and equilibrium. A new proprioceptive test is described that utilizes the computer-driven LIDO isokinetic ergometer. An overview of the computer logic, software, and testing procedure for this proprioceptive test, which can be performed with the arms or legs, is described.

  4. The friction experiments using simulated fault gouge: Rowe's constant energy ratio

    NASA Astrophysics Data System (ADS)

    Hirata, M.; Muto, J.; Nagahama, H.; Otsuki, K.

    2013-12-01

    Rowe (1962) introduced a concept called minimum energy ratio principle to get a stress-dilatancy relation of granular materials under axisymmetric stress condition, and postulated that the ratio of rate of dissipation of energy in internal friction to rate of supply of energy in the direction of the major principal stress shall be a minimum and a constant value. However, the physical basis of this principle or physical meanings of the minimum incremental energy ratio have been questioned by many investigators. So we conducted friction experiments using simulated fault gouge in a gas-medium apparatus to test Rowe's hypothesis of constant energy ratio. The friction experiments using simulated fault gouge in a gas-medium apparatus was conducted under the confining pressure 140-180 MPa, and strain rate 10-3 /s. Dry quartz powders for gouge were sandwiched into two gabbro cylinders, which were 20 mm in diameter, 40 mm in length, and cut by a 50o to their cylindrical axis. To clarify mechanical behaviors of fault gouge, we repeated holding loads at several desired values, and used strain gauges glued onto a gauge layer directly with the high-speed data acquisition systems. During holding stage, we obtained the ratio of energy rate of the major principal compressional stress to minor compression stresses, or the energy rate ratio of input energy to output one. The ratio of energy rates showed a constant value in lower energy rates, on the other hand, it deviated from the constant value in higher energy rates. According to Rowe's theory of the constant energy ratio, the change in the ratio of energy rate indicates the change in angle of internal friction. Riedel shear angle related to internal friction angle decreases with shear strain (Gu and Wong, 1994), so it can be said that the change in internal friction angle is related to microstructure development. Therefore, the energy ratio in the lower energy rates is constant and the ratio in the higher energy rates varies

  5. Rowing increases stroke volume and cardiac output to a greater extent than cycling.

    PubMed

    Horn, P; Ostadal, P; Ostadal, B

    2015-01-01

    Exercise stimulates increases in heart rate (HR), stroke volume (SV) and cardiac output (CO). These adaptive mechanisms are strongly dependent on the type of exercise. Both rowing and cycling are widely used for physical training worldwide; however, evidence regarding the differences in major hemodynamic parameters during rowing and cycling remains insufficient. Ten healthy male volunteers were randomly assigned to perform either a rowing or cycling exercise. After 20 min rest, the group who had rowed first performed the cycling exercise and vice versa. Exercise was performed at a power-to-weight ratio of 2 W/kg for 2 min. HR, SV, CO and blood pressure (BP) were measured noninvasively using pulse-wave analysis at baseline and immediately after each exercise. HR, SV and CO were significantly higher after exercise than at rest. Whereas HR was comparable between rowing and cycling, SV and CO were significantly higher after rowing than after cycling. BP was comparable among all three measurements. Rowing increased SV and CO to a greater extent than cycling, whereas HR and BP were not influenced by the type of exercise. Our data suggest that rowing leads to more extensive stimulation of cardiac contractility and/or decreases in peripheral vascular resistance compared with cycling.

  6. A parallel row-based algorithm for standard cell placement with integrated error control

    NASA Technical Reports Server (NTRS)

    Sargent, Jeff S.; Banerjee, Prith

    1989-01-01

    A new row-based parallel algorithm for standard-cell placement targeted for execution on a hypercube multiprocessor is presented. Key features of this implementation include a dynamic simulated-annealing schedule, row-partitioning of the VLSI chip image, and two novel approaches to control error in parallel cell-placement algorithms: (1) Heuristic Cell-Coloring; (2) Adaptive Sequence Length Control.

  7. The effects of color plastic mulches and row covers on the growth and yield of okra

    USDA-ARS?s Scientific Manuscript database

    Okra [Abelmoschus esculentus (l.) Moench'Clemson Spineless'] was grown on an Orangeburg sandy loam soil in shorter, AL. Okra was direct seeded in single rows. The experiment consisted of twelve experimental treatments as follows: (1) Black plastic mulch (BPM) + spunbonded row cover (RC), (2) BPM, (3...

  8. Plastic Mulches and Row Covers on the grow and production of Summer Squash.

    USDA-ARS?s Scientific Manuscript database

    Summer squash [Cucurbita pepo (L) ‘Prelude II’] was grown on an Orangeburg sandy loam soil in Shorter, AL. The summer squash was direct seeded in single rows. The experiment consisted of twelve experimental treatments as follows: (1) Black plastic mulch (BPM) + spunbonded row cover (RC), (2) BPM, (...

  9. 77 FR 15597 - Special Local Regulation; USAT Triathlon/Race Rowing Competition; Black Warrior River; Tuscaloosa...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-16

    ... The University of Alabama Women's rowing team is sponsoring a Race Rowing Competition between the... or copying at the Docket Management Facility (M-30), U.S. Department of Transportation, West Building...., Monday through Friday, except Federal holidays; and U.S. Coast Guard Sector Mobile (spw), Building...

  10. Implements and cultivation frequency to improve in-row weed control in organic peanut production

    USDA-ARS?s Scientific Manuscript database

    Weed control in organic peanut production is difficult and costly, which limits expansion of the production system. Sweep cultivation in the row middles is effective, but weeds remain in the crop row causing yield loss. Research trials were conducted in Tifton, GA to evaluate implements and freque...

  11. 33 CFR 100.724 - Annual Augusta Invitational Rowing Regatta; Savannah River, Augusta, GA.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Rowing Regatta; Savannah River, Augusta, GA. 100.724 Section 100.724 Navigation and Navigable Waters... WATERS § 100.724 Annual Augusta Invitational Rowing Regatta; Savannah River, Augusta, GA. (a) Definitions. (1) Regulated area. The regulated area is formed by a line drawn directly across the Savannah...

  12. 33 CFR 100.724 - Annual Augusta Invitational Rowing Regatta; Savannah River, Augusta, GA.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Rowing Regatta; Savannah River, Augusta, GA. 100.724 Section 100.724 Navigation and Navigable Waters... WATERS § 100.724 Annual Augusta Invitational Rowing Regatta; Savannah River, Augusta, GA. (a) Definitions. (1) Regulated area. The regulated area is formed by a line drawn directly across the Savannah...

  13. 33 CFR 100.724 - Annual Augusta Invitational Rowing Regatta; Savannah River, Augusta, GA.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Rowing Regatta; Savannah River, Augusta, GA. 100.724 Section 100.724 Navigation and Navigable Waters... WATERS § 100.724 Annual Augusta Invitational Rowing Regatta; Savannah River, Augusta, GA. (a) Definitions. (1) Regulated area. The regulated area is formed by a line drawn directly across the Savannah...

  14. 33 CFR 100.724 - Annual Augusta Invitational Rowing Regatta; Savannah River, Augusta, GA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Rowing Regatta; Savannah River, Augusta, GA. 100.724 Section 100.724 Navigation and Navigable Waters... WATERS § 100.724 Annual Augusta Invitational Rowing Regatta; Savannah River, Augusta, GA. (a) Definitions. (1) Regulated area. The regulated area is formed by a line drawn directly across the Savannah...

  15. Building Generalized Inverses of Matrices Using Only Row and Column Operations

    ERIC Educational Resources Information Center

    Stuart, Jeffrey

    2010-01-01

    Most students complete their first and only course in linear algebra with the understanding that a real, square matrix "A" has an inverse if and only if "rref"("A"), the reduced row echelon form of "A", is the identity matrix I[subscript n]. That is, if they apply elementary row operations via the Gauss-Jordan algorithm to the partitioned matrix…

  16. Single- and double-row repair for rotator cuff tears - biology and mechanics.

    PubMed

    Papalia, Rocco; Franceschi, Francesco; Vasta, Sebastiano; Zampogna, Biagio; Maffulli, Nicola; Denaro, Vincenzo

    2012-01-01

    We critically review the existing studies comparing the features of single- and double-row repair, and discuss suggestions about the surgical indications for the two repair techniques. All currently available studies comparing the biomechanical, clinical and the biological features of single and double row. Biomechanically, the double-row repair has greater performances in terms of higher initial fixation strength, greater footprint coverage, improved contact area and pressure, decreased gap formation, and higher load to failure. Results of clinical studies demonstrate no significantly better outcomes for double-row compared to single-row repair. Better results are achieved by double-row repair for larger lesions (tear size 2.5-3.5 cm). Considering the lack of statistically significant differences between the two techniques and that the double row is a high cost and a high surgical skill-dependent technique, we suggest using the double-row technique only in strictly selected patients. Copyright © 2012 S. Karger AG, Basel.

  17. Spray deposition inside multiple-row nursery trees with a laser-guided sprayer

    USDA-ARS?s Scientific Manuscript database

    Multiple-row container-grown trees require specially designed sprayers to achieve efficient spray delivery quality. A five-port air-assisted sprayer with both automatic and manual control modes was developed to discharge adequate spray deposition inside multiple-row tree plants. The sprayer resulted...

  18. Building Generalized Inverses of Matrices Using Only Row and Column Operations

    ERIC Educational Resources Information Center

    Stuart, Jeffrey

    2010-01-01

    Most students complete their first and only course in linear algebra with the understanding that a real, square matrix "A" has an inverse if and only if "rref"("A"), the reduced row echelon form of "A", is the identity matrix I[subscript n]. That is, if they apply elementary row operations via the Gauss-Jordan algorithm to the partitioned matrix…

  19. Inter-row evapotranspiration in arid and humid wine-grape vineyards

    USDA-ARS?s Scientific Manuscript database

    The architecture of wine-grape vineyards is characterized by tall plants (approx. 1.5 m) and widely spaced rows (approx. 3 m). This wide row spacing, developed to allow sunlight interception, air flow, and field operations, creates a complex system for water and energy budgets. Because of the wide r...

  20. Assessment of modification factors for a row of bolts or timber connectors

    Treesearch

    Thomas Lee Wilkinson

    1980-01-01

    When bolts or timber connectors are used in a row, with load applied parallel to the row, load will be unequally distributed among the fasteners. This study assessed methods of predicting this unequal load distribution, looked at how joint variables can affect the distribution, and compared the predictions with data existing in the literature. Presently used design...

  1. Radiometer footprint model to estimate sunlit and shaded components for row crops

    USDA-ARS?s Scientific Manuscript database

    This paper describes a geometric model for computing the relative proportion of sunlit vegetation, shaded vegetation, sunlit soil, and shaded soil appearing in a circular or elliptical radiometer footprint for row crops, where the crop rows were modeled as continuous ellipses. The model was validate...

  2. Variations in hemostatic parameters after near-maximum exercise and specific tests in athletes.

    PubMed

    Cerneca, F; Crocetti, G; Gombacci, A; Simeone, R; Tamaro, G; Mangiarotti, M A

    1999-03-01

    The clotting state of the blood changes according to the type of physical exercise to which a group of healthy subjects are subjected. We studied the behaviour of the coagulation system before and after near-maximum, specific and standardized exercise tests in three groups of males practising sports defined as demanding in terms of cardiovascular output. The study was a comparative investigation between athletes and the group of controls composed of presumably healthy males. athletes training for competitions such as marathon, rowing and weightlifting. we tested 7 rowers using the rowing machine, 12 marathon runners using the treadmill, 7 weightlifters using their own exercise equipment, and 7 healthy subjects (controls) using the cycle ergometer. during the tests we monitored heart rates, maximal oxygen intake, anaerobic threshold, respiratory quotient, maximum ventilation, and lactic acid. The following coagulation tests were performed before and after near-maximum exercise: prothrombin time (PT), partial activated thromboplastin time (PTT), fibrinogen (FBG), antithrombin III (ATIII), protein C (PC), protein S (PS), prothrombin fragment 1 + 2 (F1 + 2), tissue activator of plasminogen (t-PA) and its inhibitor (PAI). The most significant results showed a low basal PC in the rowers which decreased further after near-maximum exercise; significantly higher basal activities of ATIII, PC and PS in the marathon runners compared to the rowers; a high proportion of weightlifters showed a reduction in t-PA after exercise and an increase of PAI; the controls were the only group in which fibrinolytic activity and all the circulating anticoagulants increased after near-maximum exercise. Thus subjects who practise aerobic sports differ principally in terms of variations in inhibitors (low PC in rowers and marathon runners, increased presence of inhibitors in controls). The weightlifters did not show any significant variations, and so the kind of exercise involved (training to

  3. Predicting maximal aerobic capacity (VO2max) from the critical velocity test in female collegiate rowers.

    PubMed

    Kendall, Kristina L; Fukuda, David H; Smith, Abbie E; Cramer, Joel T; Stout, Jeffrey R

    2012-03-01

    The objective of this study was to examine the relationship between the critical velocity (CV) test and maximal oxygen consumption (VO2max) and develop a regression equation to predict VO2max based on the CV test in female collegiate rowers. Thirty-five female (mean ± SD; age, 19.38 ± 1.3 years; height, 170.27 ± 6.07 cm; body mass, 69.58 ± 0.3 1 kg) collegiate rowers performed 2 incremental VO2max tests to volitional exhaustion on a Concept II Model D rowing ergometer to determine VO2max. After a 72-hour rest period, each rower completed 4 time trials at varying distances for the determination of CV and anaerobic rowing capacity (ARC). A positive correlation was observed between CV and absolute VO2max (r = 0.775, p < 0.001) and ARC and absolute VO2max (r = 0.414, p = 0.040). Based on the significant correlation analysis, a linear regression equation was developed to predict the absolute VO2max from CV and ARC (absolute VO2max = 1.579[CV] + 0.008[ARC] - 3.838; standard error of the estimate [SEE] = 0.192 L·min(-1)). Cross validation analyses were performed using an independent sample of 10 rowers. There was no significant difference between the mean predicted VO2max (3.02 L·min(-1)) and the observed VO2max (3.10 L·min(-1)). The constant error, SEE and validity coefficient (r) were 0.076 L·min(-1), 0.144 L·min(-1), and 0.72, respectively. The total error value was 0.155 L·min(-1). The positive relationship between CV, ARC, and VO2max suggests that the CV test may be a practical alternative to measuring the maximal oxygen uptake in the absence of a metabolic cart. Additional studies are needed to validate the regression equation using a larger sample size and different populations (junior- and senior-level female rowers) and to determine the accuracy of the equation in tracking changes after a training intervention.

  4. Comparison of oxygen uptake during and after the execution of resistance exercises and exercises performed on ergometers, matched for intensity

    PubMed Central

    Freitas, Nuno Miguel; Saavedra, Francisco José; Scott, Christopher B.; dos Reis, Victor Machado; Simão, Roberto; Garrido, Nuno

    2016-01-01

    Abstract The aim of this study was to compare the values of oxygen uptake (VO2) during and after strength training exercises (STe) and ergometer exercises (Ee), matched for intensity and exercise time. Eight men (24 ± 2.33 years) performed upper and lower body cycling Ee at the individual’s ventilatory threshold (VE/VCO2). The STe session included half squats and the bench press which were performed with a load at the individual blood lactate concentration of 4 mmol/l. Both sessions lasted 30 minutes, alternating 50 seconds of effort with a 10 second transition time between upper and lower body work. The averaged overall VO2 between sessions was significantly higher for Ee (24.96 ± 3.6 ml·kg·min-1) compared to STe (21.66 ± 1.77 ml·kg·min-1) (p = 0.035), but this difference was only seen for the first 20 minutes of exercise. Absolute VO2 values between sessions did not reveal differences. There were more statistically greater values in Ee compared to STe, regarding VO2 of lower limbs (25.44 ± 3.84 ml·kg·min-1 versus 21.83 ± 2·24 ml·kg·min-1; p = 0.038) and upper limbs (24.49 ± 3.84 ml·kg·min-1 versus 21.54 ± 1.77 ml·kg·min-1; p = 0.047). There were further significant differences regarding the moment effect (p<0.0001) of both STe and Ee sessions. With respect to the moment × session effect, only VO2 5 minutes into recovery showed significant differences (p = 0.017). In conclusion, although significant increases in VO2 were seen following Ee compared to STe, it appears that the load/intensity, and not the material/equipment used for the execution of an exercise, are variables that best influence oxygen uptake. PMID:28149422

  5. Comparison of oxygen uptake during and after the execution of resistance exercises and exercises performed on ergometers, matched for intensity.

    PubMed

    Vilaça-Alves, José; Freitas, Nuno Miguel; Saavedra, Francisco José; Scott, Christopher B; Dos Reis, Victor Machado; Simão, Roberto; Garrido, Nuno

    2016-12-01

    The aim of this study was to compare the values of oxygen uptake (VO2) during and after strength training exercises (STe) and ergometer exercises (Ee), matched for intensity and exercise time. Eight men (24 ± 2.33 years) performed upper and lower body cycling Ee at the individual's ventilatory threshold (VE/VCO2). The STe session included half squats and the bench press which were performed with a load at the individual blood lactate concentration of 4 mmol/l. Both sessions lasted 30 minutes, alternating 50 seconds of effort with a 10 second transition time between upper and lower body work. The averaged overall VO2 between sessions was significantly higher for Ee (24.96 ± 3.6 ml·kg·min(-1)) compared to STe (21.66 ± 1.77 ml·kg·min(-1)) (p = 0.035), but this difference was only seen for the first 20 minutes of exercise. Absolute VO2 values between sessions did not reveal differences. There were more statistically greater values in Ee compared to STe, regarding VO2 of lower limbs (25.44 ± 3.84 ml·kg·min(-1) versus 21.83 ± 2·24 ml·kg·min(-1); p = 0.038) and upper limbs (24.49 ± 3.84 ml·kg·min(-1) versus 21.54 ± 1.77 ml·kg·min(-1); p = 0.047). There were further significant differences regarding the moment effect (p<0.0001) of both STe and Ee sessions. With respect to the moment × session effect, only VO2 5 minutes into recovery showed significant differences (p = 0.017). In conclusion, although significant increases in VO2 were seen following Ee compared to STe, it appears that the load/intensity, and not the material/equipment used for the execution of an exercise, are variables that best influence oxygen uptake.

  6. Positive ions of the first- and second-row transition metal hydrides

    NASA Technical Reports Server (NTRS)

    Pettersson, Lars G. M.; Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Partridge, Harry

    1987-01-01

    Theoretical dissociation energies for the first- and second-row transition metal hydride positive ions are critically compared against recent experimental values obtained from ion beam reactive scattering methods. Theoretical spectroscopic parameters and dipole moments are presented for the ground and several low-lying excited states. The calculations employ large Gaussian basis sets and account for electron correlation using the single-reference single- and double-excitation configuration interaction and coupled-pair-functional methods. The Darwin and mass-velocity contributions to the relativistic energy are included in the all-electron calculations on the first-row systems using first-order perturbation theory, and in the second-row systems using the Hay and Wadt relativistic effective core potentials. The theoretical D(0) values for the second-row transition metal hydride positive ions should provide a critical measure of the experimental values, which are not as refined as many of those in the first transition row.

  7. Significance of agricultural row structure on the microwave emissivity of soils

    NASA Technical Reports Server (NTRS)

    Promes, P. M.; Jackson, T. J.; O'Neill, P. E.

    1987-01-01

    A series of field experiments was carried out to extend the data base available for verifying agricultural row effect models of emissivity. The row effects model was used to simulate a data base from which an algorithm could be developed to account for row effects when the scene dielectric constant and small-scale roughness are unknown. One objective of the study was to quantify the significance of row structure and to develop a practical procedure for removing the effects of periodic row structure on the microwave emissivity of a soil in order to use the emissivity values to estimate the soil moisture. A second objective was to expand the data set available for model verification through field observations using a truck-mounted 1.4-GHz microwave radiometer.

  8. Novel ultrahigh resolution data acquisition and image reconstruction for multi-detector row CT

    SciTech Connect

    Flohr, T. G.; Stierstorfer, K.; Suess, C.; Schmidt, B.; Primak, A. N.; McCollough, C. H.

    2007-05-15

    We present and evaluate a special ultrahigh resolution mode providing considerably enhanced spatial resolution both in the scan plane and in the z-axis direction for a routine medical multi-detector row computed tomography (CT) system. Data acquisition is performed by using a flying focal spot both in the scan plane and in the z-axis direction in combination with tantalum grids that are inserted in front of the multi-row detector to reduce the aperture of the detector elements both in-plane and in the z-axis direction. The dose utilization of the system for standard applications is not affected, since the grids are moved into place only when needed and are removed for standard scanning. By means of this technique, image slices with a nominal section width of 0.4 mm (measured full width at half maximum=0.45 mm) can be reconstructed in spiral mode on a CT system with a detector configuration of 32x0.6 mm. The measured 2% value of the in-plane modulation transfer function (MTF) is 20.4 lp/cm, the measured 2% value of the longitudinal (z axis) MTF is 21.5 lp/cm. In a resolution phantom with metal line pair test patterns, spatial resolution of 20 lp/cm can be demonstrated both in the scan plane and along the z axis. This corresponds to an object size of 0.25 mm that can be resolved. The new mode is intended for ultrahigh resolution bone imaging, in particular for wrists, joints, and inner ear studies, where a higher level of image noise due to the reduced aperture is an acceptable trade-off for the clinical benefit brought about by the improved spatial resolution.

  9. Edge-to-Stem Variability in Wet-Canopy Evaporation From an Urban Tree Row

    NASA Astrophysics Data System (ADS)

    Van Stan, John T.; Norman, Zachary; Meghoo, Adrian; Friesen, Jan; Hildebrandt, Anke; Côté, Jean-François; Underwood, S. Jeffrey; Maldonado, Gustavo

    2017-07-01

    Evaporation from wet-canopy (E_C ) and stem (E_S ) surfaces during rainfall represents a significant portion of municipal-to-global scale hydrologic cycles. For urban ecosystems, E_C and E_S dynamics play valuable roles in stormwater management. Despite this, canopy-interception loss studies typically ignore crown-scale variability in E_C and assume (with few indirect data) that E_S is generally {<}2% of total wet-canopy evaporation. We test these common assumptions for the first time with a spatially-distributed network of in-canopy meteorological monitoring and 45 surface temperature sensors in an urban Pinus elliottii tree row to estimate E_C and E_S under the assumption that crown surfaces behave as "wet bulbs". From December 2015 through July 2016, 33 saturated crown periods (195 h of 5-min observations) were isolated from storms for determination of 5-min evaporation rates ranging from negligible to 0.67 mm h^{-1} . Mean E_S (0.10 mm h^{-1} ) was significantly lower (p < 0.01 ) than mean E_C (0.16 mm h^{-1} ). But, E_S values often equalled E_C and, when scaled to trunk area using terrestrial lidar, accounted for 8-13% (inter-quartile range) of total wet-crown evaporation (E_S+E_C scaled to surface area). E_S contributions to total wet-crown evaporation maximized at 33%, showing a general underestimate (by 2-17 times) of this quantity in the literature. Moreover, results suggest wet-crown evaporation from urban tree rows can be adequately estimated by simply assuming saturated tree surfaces behave as wet bulbs, avoiding problematic assumptions associated with other physically-based methods.

  10. Comparison of BR3 surveillance and vessel plates to the surrogate plates representative of the Yankee Rowe PWR vessel

    SciTech Connect

    Fabry, A.; Chaouadi, R.; Puzzolante, J.L.; Van de Velde, J.; Biemiller, E.C.; Rosinski, S.T.; Carter, R.G.

    1999-10-01

    The sister pressure vessels at the BR3 and Yankee Rowe PWR plants were operated at lower-than-usual temperature ({approx}260 C) and their plates were austenitized at higher-than-usual temperature ({approx}970 C) -- a heat treatment leading to a coarser microstructure than is typical for the fine grain plates considered in development of USNRC Regulatory Guide 1.99. The surveillance programs provided by Westinghouse for the two plants were limited to the same A302-B plate representative of the Rowe vessel upper shell plate; this material displayed outlier behavior characterized by a 41J. Charpy-V Notch shift significantly larger than predicted by Regulatory Guide 1.99. Because lower irradiation temperature and nickel alloying are generally considered detrimental to irradiation sensitivity, there was a major concern that the nickel-modified lower Rowe plate and the nickel-modified BR3 plate may become too embrittled to satisfy the toughness requirements embodied in the PTS screening criterion. This paper compares three complementary studies undertaken to clarify these uncertainties: (1) The accelerated irradiation and test program launched in 1990 by Yankee Atomic Electric Company using typical vessel plate materials containing 0.24% copper at two nickel levels: YA1, 0.63% (A533-B) and YA9, 0.19% (A302-B). These were heat-treated to produce the coarse and fine grain microstructures representative of the Yankee/BR3 and the Regulatory Guide plates, respectively; (2) The BR3 surveillance and vessel testing program; this vessel was wet-annealed in 1984, relicensed for operation till the plant shutdown in 1987, and was trepanned in early 1995; (3) The accelerated irradiations in the Belgian test reactor BR2 of the Yankee coarse grain plates YA1 and YA9 together with BR3 vessel specimens extracted at nozzle elevation, a location with negligible radiation exposure. It is contended that the PTS screening criterion was never attained by the BR3 and Rowe plates, and that the

  11. Coordinated movement of the three rows of outer hair cells is essential for cochlear amplification

    NASA Astrophysics Data System (ADS)

    Murakoshi, Michio; Suzuki, Sho; Wada, Hiroshi

    2015-12-01

    The process known as cochlear amplification is realized by coordinated movement of the outer hair cells (OHCs) in response to changes in their membrane potential. In this process, the displacement amplitude of the basilar membrane (BM) is thought to be increased, thereby leading to the high sensitivity, wide dynamic range and sharp frequency selectivity of our hearing. Unfortunately, however, OHCs are vulnerable to noise exposure, ototoxic acid, aging and so on. Previous studies have shown that exposure to intense noise causes functional loss of OHCs from the innermost row (i.e., close to the modiolus) to the outermost row (i.e., close to the cochlear wall). On the contrary, by other traumatic stimuli such as ototoxic acid, aging and ischemia, such loss of OHCs has been reported to occur from the outermost row toward the innermost row. However, how the cochlear amplification changes when coordinated movement of OHCs is impaired, that is when the OHCs in one, two or all three rows have become dysfunctional, remains unclear. In the present study, therefore, a finite element (FE) model of the gerbil cochlea, which takes the motility of OHCs into account, was developed based on our previous FE model. Using this model, changes in the displacement amplitude of the BM due to the functional loss of OHCs in one, two or all three rows were investigated and the effects of incoordination of the three rows of OHCs on cochlear amplification were estimated. Results showed that the displacement amplitude of the BM significantly decreased when either the innermost row or the outermost row of OHCs lost its function, suggesting that all three rows of OHCs are required for cochlear amplification.

  12. 30 CFR 285.303 - How long will my ROW grant or RUE grant remain in effect?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE ENERGY ALTERNATE USES OF EXISTING... Renewable Energy Activities Row Grants and Rue Grants § 285.303 How long will my ROW grant or RUE...

  13. Effect of inter-row cultivation on soil CO2 emission in a peach plantation

    NASA Astrophysics Data System (ADS)

    Tóth, E.; Farkas, Cs.; Gelybó, Gy.; Lagzi, I.

    2012-04-01

    We examined the effect of inter-row cultivation on soil CO2 emission in a peach plantation planted in 1991. The soil is Ramann type brown forest soil /Mollic Cambisol/ developed on sandy loam. Every second row in the orchard is covered with undisturbed grass, and every other row is disked (depth: 12-15cm) with a two-three-week frequency. The humus content varies from 1,69% to 2,28% in the upper 20 cm layer, where the sand, loam and clay contents are 58%, 21% and 19 %, respectively. The average annual precipitation total is 570 mm (330 mm for the growing season) at the site. During the vegetation period of 2009 soil CO2 emission measurements were carried out with static chamber method in the differently managed rows. Parallel with CO2 measurements soil volumetric water content and soil temperature were also determined. Soil microbiological properties water-extractable organic carbon (WEOC) and water-extractable nitrogen (WEN) as well as substrate-induced respiration (SIR) were determined from disturbed soil samples collected on the first measurement day. The measured soil physical properties showed that different soil management practices influence soil water content, bulk density and soil temperature as well. Soil water content was higher in the grass covered row on 10 of the 13 measurement days, the difference - which reached 10 v% - was the highest on the warmest days. Soil temperature is also different in case of disked and grass covered rows, found to be lower in the grass covered rows on every measurement days. SIR, WEOC and WEN were all higher in the grass covered row (19.45 μg CO2-C g-1 soil 36.91 μg g-1 soil, 139.36 μg g-1 soil, respectively) than in the disked row (4.88 μg CO2-C g-1 soil 25.43 μg C g-1 soil, 61.25 μg N g-1 soil, respectively) in 2009. Soil CO2 emission also differed between the two rows, grass covered rows produced higher emission in all measurements days without exemption. The difference between CO2 fluxes from the two cultivation

  14. 77 FR 25077 - Special Local Regulation; Wy-Hi Rowing Regatta, Trenton Channel; Detroit River, Wyandotte, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-27

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; Wy-Hi Rowing Regatta, Trenton... navigable waters immediately prior to, during, and immediately after the Wy-Hi Rowing Regatta. This special....35T09-0342 Special Local Regulation; Wy-Hi Rowing Regatta, Wyandotte, MI. (a) Regulated Area. A...

  15. 78 FR 25572 - Special Local Regulation; Wy-Hi Rowing Regatta, Trenton Channel; Detroit River, Wyandotte, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-02

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; Wy-Hi Rowing Regatta, Trenton... navigable waters immediately prior to, during, and immediately after the Wy-Hi Rowing Regatta. This special... to read as follows: Sec. 100.T09-0287 Special Local Regulation; Wy-Hi Rowing Regatta, Wyandotte, MI...

  16. Volume and crown characteristics of juvenile loblolly pine grown at various ratios of between and within row spacings

    Treesearch

    John R. Britt; Jason P. Reynolds

    2013-01-01

    In plantation forestry, several silvicultural treatments can be row oriented. When rows are treated individually, planting trees in wider rows may result in lower silvicultural treatment cost, facilitate future operations, such as thinning and fire fighting, and provide a longer period with open canopy conditions. All these scenarios could provide benefit to landowners...

  17. Stiffness matrix formulation for double row angular contact ball bearings: Analytical development and validation

    NASA Astrophysics Data System (ADS)

    Gunduz, Aydin; Singh, Rajendra

    2013-10-01

    Though double row angular contact ball bearings are widely used in industrial, automotive, and aircraft applications, the scientific literature on double row bearings is sparse. It is also shown that the stiffness matrices of two single row bearings may not be simply superposed to obtain the stiffness matrix of a double row bearing. To overcome the deficiency in the literature, a new, comprehensive, analytical approach is proposed based on the Hertzian theory for back-to-back, face-to-face, and tandem arrangements. The elements of the five-dimensional stiffness matrix for double row angular contact ball bearings are computed given either the mean bearing displacement or the mean load vector. The diagonal elements of the proposed stiffness matrix are verified with a commercial code for all arrangements under three loading scenarios. Some changes in stiffness coefficients are investigated by varying critical kinematic and geometric parameters to provide more insight. Finally, the calculated natural frequencies of a shaft-bearing experiment are successfully compared with measurements, thus validating the proposed stiffness formulation. For double row angular contact ball bearings, the moment stiffness and cross-coupling stiffness terms are significant, and the contact angle changes under loads. The proposed formulation is also valid for paired (duplex) bearings which behave as an integrated double row unit when the surrounding structural elements are sufficiently rigid.

  18. Arthroscopic double-row suture anchor fixation of minimally displaced greater tuberosity fractures.

    PubMed

    Ji, Jong-Hun; Kim, Weon-Yoo; Ra, Ki-Hang

    2007-10-01

    In cases of displaced greater tuberosity fractures, treatments by arthroscopic-assisted reduction and percutaneous screw fixation have been reported. However, in cases in which there is a comminuted fracture or a minimally displaced fracture combined with concomitant lesions such as rotator cuff tear or labral pathology, it is difficult to reduce the fracture and to treat other pathologies by use of a percutaneous screw. Recently, many surgeons have used the double-row repair method in rotator cuff repair, which provides a tendon-bone interface better suited for biologic healing and restoring normal anatomy. In accordance with this method, we used the arthroscopic technique of double-row suture anchor fixation for a minimally displaced greater tuberosity fracture without additional incision. Initially, debridement was performed on the fracture surface by use of a shaver, and the medial-row anchor was inserted through the anterior portal or the intact cuff. Two lateral-row anchors were inserted just anterior and posterior to the lower margin of the fractured fragment under C-arm guidance. The medial-row sutures and lateral-row sutures were then placed. Arthroscopic double-row suture anchor fixation of a displaced greater tuberosity fracture restores the original footprint of the rotator cuff and normal tendon-bone interface of the displaced greater tuberosity fracture.

  19. The effect of row structure on soil moisture retrieval accuracy from passive microwave data.

    PubMed

    Xingming, Zheng; Kai, Zhao; Yangyang, Li; Jianhua, Ren; Yanling, Ding

    2014-01-01

    Row structure causes the anisotropy of microwave brightness temperature (TB) of soil surface, and it also can affect soil moisture retrieval accuracy when its influence is ignored in the inversion model. To study the effect of typical row structure on the retrieved soil moisture and evaluate if there is a need to introduce this effect into the inversion model, two ground-based experiments were carried out in 2011. Based on the observed C-band TB, field soil and vegetation parameters, row structure rough surface assumption (Q p model and discrete model), including the effect of row structure, and flat rough surface assumption (Q p model), ignoring the effect of row structure, are used to model microwave TB of soil surface. Then, soil moisture can be retrieved, respectively, by minimizing the difference of the measured and modeled TB. The results show that soil moisture retrieval accuracy based on the row structure rough surface assumption is approximately 0.02 cm(3)/cm(3) better than the flat rough surface assumption for vegetated soil, as well as 0.015 cm(3)/cm(3) better for bare and wet soil. This result indicates that the effect of row structure cannot be ignored for accurately retrieving soil moisture of farmland surface when C-band is used.

  20. The Effect of Row Structure on Soil Moisture Retrieval Accuracy from Passive Microwave Data

    PubMed Central

    Xingming, Zheng; Kai, Zhao; Yangyang, Li; Jianhua, Ren; Yanling, Ding

    2014-01-01

    Row structure causes the anisotropy of microwave brightness temperature (TB) of soil surface, and it also can affect soil moisture retrieval accuracy when its influence is ignored in the inversion model. To study the effect of typical row structure on the retrieved soil moisture and evaluate if there is a need to introduce this effect into the inversion model, two ground-based experiments were carried out in 2011. Based on the observed C-band TB, field soil and vegetation parameters, row structure rough surface assumption (Qp model and discrete model), including the effect of row structure, and flat rough surface assumption (Qp model), ignoring the effect of row structure, are used to model microwave TB of soil surface. Then, soil moisture can be retrieved, respectively, by minimizing the difference of the measured and modeled TB. The results show that soil moisture retrieval accuracy based on the row structure rough surface assumption is approximately 0.02 cm3/cm3 better than the flat rough surface assumption for vegetated soil, as well as 0.015 cm3/cm3 better for bare and wet soil. This result indicates that the effect of row structure cannot be ignored for accurately retrieving soil moisture of farmland surface when C-band is used. PMID:25386626

  1. Direction-specific recruitment of rotator cuff muscles during bench press and row.

    PubMed

    Wattanaprakornkul, Duangjai; Halaki, Mark; Cathers, Ian; Ginn, Karen A

    2011-12-01

    Recent studies indicate that rotator cuff (RC) muscles are recruited in a reciprocal, direction-specific pattern during shoulder flexion and extension exercises. The main purpose of this study was to determine if similar reciprocal RC recruitment occurs during bench press (flexion-like) and row (extension-like) exercises. In addition, shoulder muscle activity was comprehensively compared between bench press and flexion; row and extension; and bench press and row exercises. Electromyographic (EMG) activity was recorded from 9 shoulder muscles sites in 15 normal volunteers. All exercises were performed at 20, 50 and 70% of subjects' maximal load. EMG data were normalized to standard maximal voluntary contractions. Infraspinatus activity was significantly higher than subscapularis during bench press, with the converse pattern during the row exercise. Significant differences in activity levels were found in pectoralis major, deltoid and trapezius between the bench press and flexion exercises and in lower trapezius between the row and extension exercises. During bench press and row exercises, the recruitment pattern in each active muscle did not vary with load. During bench press and row exercises, RC muscles contract in a reciprocal direction-specific manner in their role as shoulder joint dynamic stabilizers to counterbalance antero-posterior translation forces. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Single-Versus Double-Row Arthroscopic Rotator Cuff Repair in Massive Tears

    PubMed Central

    Wang, EnZhi; Wang, Liang; Gao, Peng; Li, ZhongJi; Zhou, Xiao; Wang, SongGang

    2015-01-01

    Background It is a challenge for orthopaedic surgeons to treat massive rotator cuff tears. The optimal management of massive rotator cuff tears remains controversial. Therefore, the goal of this study was to compare arthroscopic single- versus double-row rotator cuff repair with a larger sample size. Material/Methods Of the subjects with massive rotator cuff tears, 146 were treated using single-row repair, and 102 were treated using double-row repair. Pre- and postoperative functional outcomes and radiographic images were collected. The clinical outcomes were evaluated for a minimum of 2 years. Results No significant differences were shown between the groups in terms of functional outcomes. Regarding the integrity of the tendon, a lower rate of post-treatment retear was observed in patients who underwent double-row repair compared with single-row repair. Conclusions The results suggest that double-row repair is relatively superior in shoulder ROM and the strength of tendon compared with single-row repair. Future studies involving more patients in better-designed randomized controlled trials will be required. PMID:26017641

  3. Evaluation of native bees as pollinators of cucurbit crops under floating row covers.

    PubMed

    Minter, Logan M; Bessin, Ricardo T

    2014-10-01

    Production of cucurbit crops presents growers with numerous challenges. Several severe pests and diseases can be managed through the use of rotation, trap cropping, mechanical barriers, such as row covers, and chemical applications. However, considerations must also be made for pollinating insects, as adequate pollination affects the quantity and quality of fruit. Insecticides may negatively affect pollinators; a concern enhanced in recent years due to losses in managed Apis melifera L. colonies. Row covers can be used in place of chemical control before pollination, but when removed, pests have access to fields along with the pollinators. If pollination services of native bees could be harnessed for use under continuous row covers, both concerns could be balanced for growers. The potential of two bee species which specialize on cucurbit flowers, Peponapis pruinosa Say and Xenoglossa strenua Cresson, were assessed under continuous row covers, employed over acorn squash. Experimental treatments included plots with either naturally or artificially introduced bees under row covers and control plots with row covers either permanently removed at crop flowering, or employed continuously with no added pollinating insects. Pests in plots with permanently removed row covers were managed using standard practices used in certified organic production. Marketable yields from plots inoculated with bees were indistinguishable from those produced under standard practices, indicating this system would provide adequate yields to growers without time and monetary inputs of insecticide applications. Additionally, application of this technique was investigated for muskmelon production and discussed along with considerations for farm management.

  4. Valence calculations of binding energies of mid-row lanthanides

    NASA Astrophysics Data System (ADS)

    O'Malley, Steven M.; Beck, Donald R.

    2008-05-01

    Binding energies of mid-row lanthanides have been calculated by taking advantage of the >90% LS purity of the 4f^n subgroups of their neutral ground states ootnotetextAtomic Energy Levels -- The Rare-Earth Elements, edited by W. C. Martin, R. Zalubas, and L. Hagan, Natl. Bur. Stand. Ref. Data Ser. Natl. Bur. Stand. (U.S.) Circ. No. 60 (U.S. GPO, Washington, D.C., 1978).. As described in our recent work on Nd^- ootnotetextS. M. O'Malley and D. R. Beck, Phy. Rev. A 77, 012505 (2008)., the 4f^n electrons were treated as core-like and restricted to a single LS term throughout all Dirac-Fock and correlation configurations, resulting in manageable relativistic configuration-interaction calculations for these computationally complex systems. Several weakly bound 6p attachments (<200 meV) were found for each negative ion, and these were carefully analyzed with respect to approximate LS total configuration as well as the j's of the the 4f^n subgroup and 6p electron.

  5. On Drawn K-In-A-Row Games

    NASA Astrophysics Data System (ADS)

    Chiang, Sheng-Hao; Wu, I.-Chen; Lin, Ping-Hung

    In 2005, Wu and Huang [9] presented a generalized family of k-in-a-row games. The current paper simplifies the family to Connect(k, p). Two players alternately place p stones on empty squares of an infinite board in each turn. The player who first obtains k consecutive stones of his own horizontally, vertically, diagonally wins. A Connect(k, p)game is drawn if both have no winning strategy. Given p, this paper derives the value k draw(p), such that Connect(k draw(p), p) is drawn, as follows. (1) k draw(2) = 11. (2) For all p ≥ 3, k draw(p) = 3p+3d+8, where d is a logarithmic function of p. So, the ratio k draw(p)/p is approximate to 3 for sufficiently large p. To our knowledge, our k draw(p) are currently the smallest for all 2 ≤ p < 1000, except for p = 3.

  6. Rows of ATP Synthase Dimers in Native Mitochondrial Inner Membranes

    PubMed Central

    Buzhynskyy, Nikolay; Sens, Pierre; Prima, Valerie; Sturgis, James N.; Scheuring, Simon

    2007-01-01

    The ATP synthase is a nanometric rotary machine that uses a transmembrane electrochemical gradient to form ATP. The structures of most components of the ATP synthase are known, and their organization has been elucidated. However, the supramolecular assembly of ATP synthases in biological membranes remains unknown. Here we show with submolecular resolution the organization of ATP synthases in the yeast mitochondrial inner membranes. The atomic force microscopy images we have obtained show how these molecules form dimers with characteristic 15 nm distance between the axes of their rotors through stereospecific interactions of the membrane embedded portions of their stators. A different interaction surface is responsible for the formation of rows of dimers. Such an organization elucidates the role of the ATP synthase in mitochondrial morphology. Some dimers have a different morphology with 10 nm stalk-to-stalk distance, in line with ATP synthases that are accessible to IF1 inhibition. Rotation torque compensation within ATP synthase dimers stabilizes the ATP synthase structure, in particular the stator-rotor interaction. PMID:17557793

  7. Classification of lung area using multidetector-row CT images

    NASA Astrophysics Data System (ADS)

    Mukaibo, Tsutomu; Kawata, Yoshiki; Niki, Noboru; Ohmatsu, Hironobu; Kakinuma, Ryutaro; Eguchi, Kenji; Kaneko, Masahiro; Moriyama, Noriyuki

    2002-05-01

    Recently, we can get high quality images in the short time for the progress of X-ray CT scanner. And the three dimensional (3-D) analysis of pulmonary organs using multidetector-row CT (MDCT) images, is expected. This paper presents a method for classifying lung area into each lobe using pulmonary MDCT images of the whole lung area. It is possible to recognize the position of nodule by classifying lung area into these lobes. The structure of lungs differs on the right one and left one. The right lung is divided into three domains by major fissure and minor fissure. And, the left lung is divided into two domains by major fissure. Watching MDCT images carefully, we find that the surroundings of fissures have few blood vessels. Therefore, lung area is classified by extraction of the domain that the distance from pulmonary blood vessels is large and connective search of these extracted domains. These extraction and search are realized by 3-D weighted Hough transform.

  8. On the transonic aerodynamics of a compressor blade row

    NASA Technical Reports Server (NTRS)

    Erickson, J. C., Jr.; Lordi, J. A.; Rae, W. J.

    1971-01-01

    Linearized analyses have been carried out for the induced velocity and pressure fields within a compressor blade row operating in an infinite annulus at transonic Mach numbers of the flow relative to the blades. In addition, the relationship between the induced velocity and the shape of the mean blade surface has been determined. A computational scheme has been developed for evaluating the blade mean surface ordinates and surface pressure distributions. The separation of the effects of a specified blade thickness distribution from the effects of a specified distribution of the blade lift has been established. In this way, blade mean surface shapes that are necessary for the blades to be locally nonlifting have been computed and are presented for two examples of blades with biconvex parabolic arc sections of radially tapering thickness. Blade shapes that are required to achieve a zero thickness, uniform chordwise loading, constant work spanwise loading are also presented for two examples. In addition, corresponding surface pressure distributions are given. The flow relative to the blade tips has a high subsonic Mach number in the examples that have been computed. The results suggest that at near-sonic relative tip speeds the effective blade shape is dominated by the thickness distribution, with the lift distribution playing only a minor role.

  9. Supplemental basis functions for the second transition row elements

    NASA Technical Reports Server (NTRS)

    Walch, S. P.; Nelin, C. J.; Bauschlicher, C. W., Jr.

    1983-01-01

    It is noted that for molecular calculations, the basis sets presented by Huzinaga (1977) need to be augmented by (1) 5p functions to describe the 5s - 5p near degeneracy; (2) a diffuse 4d function to provide for a balanced description of the 5s2 4dn, 5s1 4d(n+1), and 4d(n+2) states of the atom; and (3) a set of 4f functions to correlate the 4d functions. Here, the diffuse 4d function is similar in function to the diffuse 3d function for the first transition row elements recommended by Hay (1977). A table is included giving the optimized values for the diffuse 4d, the 5p, and 4f (STO exponent) functions. The diffuse 4d function and the 5p functions are optimized at the SCF level on the basis of the 5s1 4d(n+1) state (except for Pd, which is optimized for the 4d10 state) and the 5s1 5p1 4dn state, respectively. The table also gives the energies and the atomic symmetries for each of the SCF calculations.

  10. Characterization of Genome-Wide Variation in Four-Row Wax, a Waxy Maize Landrace with a Reduced Kernel Row Phenotype.

    PubMed

    Liu, Hanmei; Wang, Xuewen; Wei, Bin; Wang, Yongbin; Liu, Yinghong; Zhang, Junjie; Hu, Yufeng; Yu, Guowu; Li, Jian; Xu, Zhanbin; Huang, Yubi

    2016-01-01

    In southwest China, some maize landraces have long been isolated geographically, and have phenotypes that differ from those of widely grown cultivars. These landraces may harbor rich genetic variation responsible for those phenotypes. Four-row Wax is one such landrace, with four rows of kernels on the cob. We resequenced the genome of Four-row Wax, obtaining 50.46 Gb sequence at 21.87× coverage, then identified and characterized 3,252,194 SNPs, 213,181 short InDels (1-5 bp) and 39,631 structural variations (greater than 5 bp). Of those, 312,511 (9.6%) SNPs were novel compared to the most detailed haplotype map (HapMap) SNP database of maize. Characterization of variations in reported kernel row number (KRN) related genes and KRN QTL regions revealed potential causal mutations in fea2, td1, kn1, and te1. Genome-wide comparisons revealed abundant genetic variations in Four-row Wax, which may be associated with environmental adaptation. The sequence and SNP variations described here enrich genetic resources of maize, and provide guidance into study of seed numbers for crop yield improvement.

  11. Does management intensity in inter rows effect soil physical properties in Austrian and Romanian vineyards?

    NASA Astrophysics Data System (ADS)

    Bauer, Thomas; Strauss, Peter; Stiper, Katrin; Klipa, Vladimir; Popescu, Daniela; Winter, Silvia; Zaller, Johann G.

    2016-04-01

    Successful viticulture is mainly influenced by soil and climate. The availability of water during the growing season highly influences wine quality and quantity. To protect soil from being eroded most of the winegrowers keep the inter row zones of the vineyards green. Greening also helps to provide water-stress to the grapes for harvesting high quality wines. However, these greening strategies concerning the intensity of inter row management differ from farm to farm and are mainly based on personal experience of the winegrowers. However to what extent different inter row management practices affect soil physical properties are not clearly understood yet. To measure possible effects of inter row management in vineyards on soil physical parameters we selected paired vineyards with different inter row management in Austria and Romania. In total more than 7000 soil analysis were conducted for saturated and unsaturated hydraulic conductivity, soil water retention, water stable aggregates, total organic carbon, cation exchange capacity, potassium, phosphorous, soil texture, bulk density and water infiltration. The comparison between high intensity management with at least one soil disturbance per year, medium intensity with one soil disturbance every second inter row per year and low intensity management with no soil disturbance since at least 5 years indicates that investigated soil physical properties did not improve for the upper soil layer (3-8cm). This is in contrast to general perceptions of improved soil physical properties due to low intensity of inter row management, i.e. permanent vegetated inter rows. This may be attributed to long term and high frequency mechanical stress by agricultural machinery in inter rows.

  12. New Slater-type orbital basis sets for first row transition elements

    NASA Astrophysics Data System (ADS)

    Bernardo, L. A. G.; Sordo, J. A.

    1986-08-01

    A comparative study, at the atomic level, of the quality of eight Slater-type orbitals (STO) basis sets has been carried out for the first row transition elements. Two new basis sets are proposed for these elements: the β1 basis set (small-size-type) and the α2 basis set (intermediate-size-type). Both basis sets have been developed according to the so-called δ test [J. A. Sordo and L. Pueyo, Int. J. Quantum Chem. XXVIII, 687 (1985)]. The results suggest that the errors detected by means of the δ test could be responsible for the wrong ordering predicted by 2-ζ (and lower quality basis sets) for the 4s13d10 (2S) and 4s23d9(2D) states in Cu. All the quality tests used indicated that β1 basis sets would be very appropriate for performing economical molecular calculations and that α2 basis sets, with only one STO more than 2-ζ basis sets, would provide atomic results near the Hartree-Fock limit.

  13. Experimental investigation of chair type, row spacing, occupants, and carpet on theatre chair absorption.

    PubMed

    Choi, Young-Ji; Bradley, John S; Jeong, Dae-Up

    2015-01-01

    This paper examines how the individual variations of chair type, row spacing, as well as the presence of occupants and carpet, combine to influence the absorption characteristics of theater chairs as a function of sample perimeter-to-area (P/A) ratios. Scale models were used to measure the interactive effects of the four test variables on the chair absorption characteristics, avoiding the practical difficulties of full scale measurements. All of the test variables led to effects that could lead to important changes to auditorium acoustics conditions. At mid and higher frequencies, the various effects can usually be explained as due to, more or less, porous absorbing material. In the 125 and 250 Hz octave bands, the major changes were attributed to resonant absorbing mechanisms. The results indicate that for accurate predictions of the effective absorption of the chairs in an auditorium, one should use the P/A method and reverberation chamber tests of the chair absorption coefficients to predict the absorption coefficients of each block of chairs and use these results as input in a room acoustics computer model of the auditorium. The application of these results to auditorium acoustics design is described, more approximate approaches are considered, and relations to existing methods are discussed.

  14. Simultaneous Rotator Cuff Repair and Arthroscopic Biceps Tenodesis Using Lateral Row Anchor

    PubMed Central

    Levy, Jonathan C.

    2012-01-01

    Treatment of concomitant long head of the biceps pathology in the setting of rotator cuff repair is often required. When a tenodesis of the biceps is used, additional anchors and surgical dissection are typically required. This adds additional surgical time, morbidity of additional surgical dissection, and additional anchor load and cost. We describe a novel technique for arthroscopic biceps tenodesis that uses the anterior lateral row anchor of a double-row rotator cuff repair to simultaneously secure the biceps tenodesis and rotator cuff tear. This technique provides a simple, reproducible, cost-effective means of performing a simultaneous biceps tenodesis and double-row rotator cuff repair. PMID:23766961

  15. Diurnal changes in reflectance factor due to Sun-row direction interactions

    NASA Technical Reports Server (NTRS)

    Bauer, M. E. (Principal Investigator); Vanderbilt, V. C.; Kollenkark, J. C.; Biehl, L. L.; Robinson, B. F.; Ranson, K. J.

    1981-01-01

    Over a two year period, data were collected regarding the canopies of soybeans grown in rows in planter boxes placed on a turntable in an effort to investigate changes in the spectral reflectance factor related to row direction, Sun direction, soil background, and crop development stage. Results demonstrate that the direction of rows in a soybean canopy can affect the reflectance factor of the canopy by as much as 230%. The results for the red spectral region tend to support the validity of canopy reflectance models; results for the infrared region do not.

  16. The relationship of nitrate concentrations in streams to row crop land use in Iowa

    USGS Publications Warehouse

    Schilling, K.E.; Libra, R.D.

    2000-01-01

    The relationship between row crop land use and nitrate N concentrations in surface water was evaluated for 15 Iowa watersheds ranging from 1002 to 2774 km2 and 10 smaller watersheds ranging from 47 to 775 km2 for the period 1996 to 1998. The percentage of land in row crop varied from 24 to >87% in the 15 large watersheds, and mean annual NO3-N concentrations ranged from 0.5 to 10.8 mg/L. In the small watersheds, row crop percentage varied from 28 to 87% and mean annual NO3-N concentrations ranged from 3.0 to 10.5 mg/L. In both cases, nitrate N concentrations were directly related to the percentage of row crop in the watershed (p 87% in the 15 large watersheds, and mean annual NO3-N concentrations ranged from 0.5 to 10.8 mg/L. In the small watersheds, row crop percentage varied from 28 to 87% and mean annual NO3-N concentrations ranged from 3.0 to 10.5 mg/L. In both cases, nitrate N concentrations were directly related to the percentage of row crop in the watershed (p<0.0003). Linear regression showed similar slope for both sets of watersheds (0.11) suggesting that average annual surface water nitrate concentrations in Iowa, and possibly similar agricultural areas in the midwestern USA, can be approximated by multiplying a watershed's row crop percentage by 0.1. Comparing the Iowa watershed data with similar data collected at a subwatershed scale in Iowa (0.1 to 8.1 km2) and a larger midcontinent scale (7300 to 237 100 km2) suggests that watershed scale affects the relationship of nitrate concentration and land use. The slope of nitrate concentration versus row crop percentage decreases with increasing watershed size.Mean nitrate concentrations and row crop land use were summarized for 15 larger and ten smaller watersheds in Iowa, and the relationship between NO3 concentration and land use was examined. Linear regression of mean NO3 concentration and percent row crop was highly significant for both sets of watershed data, but a stronger correlation was noted in the

  17. Results and analyses for irradiation/anneal experiments conducted on Yankee Rowe reactor pressure vessel surrogate materials. Final report

    SciTech Connect

    Biemiller, E.C.

    1995-12-01

    The Yankee Atomic Electric Company test irradiation program was implemented to characterize the irradiation response of representative Yankee Rowe reactor vessel beltline plate and weld materials and to remove uncertainties in the analysis of existing irradiation data on the Yankee Rowe reactor vessel steel. The effect of plate nickel content and microstructure on irradiation damage sensitivity was assessed. Typical reactor vessel plate materials each containing 0.24% (by weight) copper, but different nickel contents at 0.63% and 0.19%, were heat treated to produce different microstructures in the test materials. A Linde 80 weld containing 0.30% copper and 1.00% nickel was produced and heat treated to test microstructure effects on the irradiation response of weld metal. Materials taken from plate surface locations (vs 1/4 thickness) were included to test whether or not the improved toughness properties of the plate surface layer, resulting from a rapid quench, is maintained after irradiation. Irradiations were conducted at two irradiation temperatures (500{degrees}F and 550{degrees}F) to determine the effect of irradiation temperature on embrittlement. An annealing test matrix was also initiated to study the potential for a 650{degrees}F anneal. A major irradiation/annealing/reirradiation study was conducted by the DOE`s LWR Technology Center at Sandia National Laboratories (SNL), using an irradiation temperature of 550{degrees}F and a 850{degrees}F anneal. The results of the irradiation testing and the DOE/SNL annealing study show an irradiation temperature effect that is not consistent but, varies with the materials tested. The test results demonstrate that for nickel bearing steels, the superior toughness of plate surface material is maintained even after irradiation to high fluences and for the copper content tested, nickel has little effect on irradiation response.

  18. Spreadsheet Calculations for Jets in Crossflow: Opposed Rows of Inline and Staggered Holes and Single and Opposed Rows with Alternating Hole Sizes

    NASA Technical Reports Server (NTRS)

    Holdeman, James D.; Clisset, James R.; Moder, Jeffrey P.

    2010-01-01

    The primary purpose of this jet-in-crossflow study was to calculate expected results for two configurations for which limited or no experimental results have been published: (1) cases of opposed rows of closely-spaced jets from inline and staggered round holes and (2) rows of jets from alternating large and small round holes. Simulations of these configurations were performed using an Excel (Microsoft Corporation) spreadsheet implementation of a NASA-developed empirical model which had been shown in previous publications to give excellent representations of mean experimental scalar results suggesting that the NASA empirical model for the scalar field could confidently be used to investigate these configurations. The supplemental Excel spreadsheet is posted with the current report on the NASA Glenn Technical Reports Server (http://gltrs.grc.nasa.gov) and can be accessed from the Supplementary Notes section as TM-2010-216100-SUPPL1.xls. Calculations for cases of opposed rows of jets with the orifices on one side shifted show that staggering can improve the mixing, particularly for cases where jets would overpenetrate slightly if the orifices were in an aligned configuration. The jets from the larger holes dominate the mixture fraction for configurations with a row of large holes opposite a row of smaller ones although the jet penetration was about the same. For single and opposed rows with mixed hole sizes, jets from the larger holes penetrated farther. For all cases investigated, the dimensionless variance of the mixture fraction decreased significantly with increasing downstream distance. However, at a given downstream distance, the variation between cases was small.

  19. Treatment of acute perilunate dislocations: ORIF versus proximal row carpectomy.

    PubMed

    Muller, T; Hidalgo Diaz, J J; Pire, E; Prunières, G; Facca, S; Liverneaux, P

    2017-02-01

    Some authors have proposed performing proximal row carpectomy (PRC) as the initial treatment for perilunate dislocations. The goal of this retrospective study was to compare the results of a cohort of perilunate dislocation cases that were operated by open reduction and internal fixation (ORIF) or by PRC between 2006 and 2011. The cohort consisted of 21 men with a mean age of 33years, who either had an isolated perilunate dislocation (7 cases) or a fracture-dislocation (14 cases). All dislocations were dorsal, with 10 stage I and 12 stage II. Thirteen patients had been treated by ORIF (group 1) a mean of 1.2days after the injury. Eight patients had been treated by PRC (group 2) a mean of 18.7days after the injury. Immobilization time was 6-12weeks in group 1 and 2weeks in group 2. The mean operative time was 95minutes in group 1 and 65minutes in group 2. After a mean follow-up of 35months, the following outcomes were found for groups 1 and 2, respectively: pain 3/10 and 1/10, strength 77% and 73%, strength in supination 79% and 93%, strength in pronation 67% and 95%, QuickDASH 27/100 and 16/100, PRWE 43/150 and 15.5/150, flexion 69% and 57%, extension 84% and 58%, pronation 97% and 103%, supination 98% and 97%. There were four cases of osteoarthritis in both groups. Treatment of acute perilunate dislocations by PRC leads to medium-term results that are at least as good as those with ORIF treatment. The surgery duration is shorter with PRC, as is the immobilization period. Retrospective comparative. III. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. Meniscal Allograft Interposition Combined with Proximal Row Carpectomy.

    PubMed

    Steiner, Murphy M; Willsey, Matthew R; Werner, Frederick W; Harley, Brian J; Klein, Shay; Setter, Kevin J

    2017-02-01

    Background Proximal row carpectomy (PRC) is contraindicated in wrists with preexisting arthritis of the proximal capitate or radiolunate fossa. Patients with these conditions frequently pursue wrist arthrodesis with its associated functional limitations. Questions/Purposes The purpose of this study was to evaluate the results of using lateral meniscal allograft interposition (LMAI), in combination with PRC, in patients with symptomatic wrist arthritis. The primary question is whether this allograft will allow wrist function comparable to that in patients having only a PRC. A secondary question was to determine the short-term longevity of the allograft. Patients/Method Between 2006 and 2012, nine wrists underwent PRC with LMAI. Patient demographics and rates of complication or graft failure were determined. During independent clinical exams, functional outcomes were reviewed, patients completed a Disabilities of the Arm, Shoulder, and Hand (DASH) scores, and radiographs were taken. Results Four patients met the inclusion criteria, having clinical follow-up at an average of 4.2 years. DASH scores at the time of follow-up ranged from 9 to 33, with an average of 24. Average radiocapitate joint space in the first postoperative radiograph was 2.8 mm compared with 1.8 mm at the time of final follow-up. No wrists went on to arthrodesis. Conclusion Early outcomes of PRC with LMAI are comparable to those results found in the literature of PRC alone. LMAI with PRC may be a valid short-term option as a motion-preserving procedure in those patients contraindicated to having a PRC alone. Level of Evidence Level IV.