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Sample records for voluntary leg extension

  1. Voluntary Movement Frequencies in Submaximal One- and Two-Legged Knee Extension Exercise and Pedaling.

    Science.gov (United States)

    Stang, Julie; Wiig, Håvard; Hermansen, Marte; Hansen, Ernst Albin

    2016-01-01

    Understanding of behavior and control of human voluntary rhythmic stereotyped leg movements is useful in work to improve performance, function, and rehabilitation of exercising, healthy, and injured humans. The present study aimed at adding to the existing understanding within this field. To pursue the aim, correlations between freely chosen movement frequencies in relatively simple, single-joint, one- and two-legged knee extension exercise were investigated. The same was done for more complex, multiple-joint, one- and two-legged pedaling. These particular activities were chosen because they could be considered related to some extent, as they shared a key aspect of knee extension, and because they at the same time were different. The activities were performed at submaximal intensities, by healthy individuals (n = 16, thereof eight women; 23.4 ± 2.7 years; 1.70 ± 0.11 m; 68.6 ± 11.2 kg). High and fair correlations (R-values of 0.99 and 0.75) occurred between frequencies generated with the dominant leg and the nondominant leg during knee extension exercise and pedaling, respectively. Fair to high correlations (R-values between 0.71 and 0.95) occurred between frequencies performed with each of the two legs in an activity, and the two-legged frequency performed in the same type of activity. In general, the correlations were higher for knee extension exercise than for pedaling. Correlations between knee extension and pedaling frequencies were of modest occurrence. The correlations between movement frequencies generated separately by each of the legs might be interpreted to support the following working hypothesis, which was based on existing literature. It is likely that involved central pattern generators (CPGs) of the two legs share a common frequency generator or that separate frequency generators of each leg are attuned via interneuronal connections. Further, activity type appeared to be relevant. Thus, the apparent common rhythmogenesis for the two legs appeared

  2. Voluntary movement frequencies in submaximal one- and two-legged knee extension exercise and pedaling

    Directory of Open Access Journals (Sweden)

    Julie Sørbø Stang

    2016-02-01

    Full Text Available Understanding of behavior and control of human voluntary rhythmic stereotyped leg movements is useful in work to improve performance, function, and rehabilitation of exercising, healthy, and injured humans. The present study aimed at adding to the existing understanding within this field. To pursue the aim, correlations between freely chosen movement frequencies in relatively simple, single-joint, one- and two-legged knee extension exercise were investigated. The same was done for more complex, multiple-joint, one- and two-legged pedaling. These particular activities were chosen because they could be considered related to some extent, as they shared a key aspect of knee extension, and because they at the same time were different. The activities were performed at submaximal intensities, by healthy individuals (n=16, thereof 8 women; 23.4±2.7 years; 1.70±0.11 m; 68.6±11.2 kg.High and fair correlations (R-values of 0.99 and 0.75 occurred between frequencies generated with the dominant leg and the nondominant leg during knee extension exercise and pedaling, respectively. Fair to high correlations (R-values between 0.71 and 0.95 occurred between frequencies performed with each of the two legs in an activity, and the two-legged frequency performed in the same type of activity. In general, the correlations were higher for knee extension exercise than for pedaling. Correlations between knee extension and pedaling frequencies were of modest occurrence.The correlations between movement frequencies generated separately by each of the legs might be interpreted to support the following working hypothesis, which was based on existing literature. It is likely that involved central pattern generators (CPGs of the two legs share a common frequency generator or that separate frequency generators of each leg are attuned via interneuronal connections. Further, activity type appeared to be relevant. Thus, the apparent common rhythmogenesis for the two legs

  3. Impaired Interlimb Coordination of Voluntary Leg Movements in Poststroke Hemiparesis

    Science.gov (United States)

    Tseng, Shih-Chiao

    2010-01-01

    Appropriate interlimb coordination of the lower extremities is particularly important for a variety of functional human motor behaviors such as jumping, kicking a ball, or simply walking. Specific interlimb coordination patterns may be especially impaired after a lesion to the motor system such as stroke, yet this has not been thoroughly examined to date. The purpose of this study was to investigate the motor deficits in individuals with chronic stroke and hemiparesis when performing unilateral versus bilateral inphase versus bilateral antiphase voluntary cyclic ankle movements. We recorded ankle angular trajectories and muscle activity from the dorsiflexors and plantarflexors and compared these between subjects with stroke and a group of healthy age-matched control subjects. Results showed clear abnormalities in both the kinematics and EMG of the stroke subjects, with significant movement degradation during the antiphase task compared with either the unilateral or the inphase task. The abnormalities included prolonged cycle durations, reduced ankle excursions, decreased agonist EMG bursts, and reduced EMG modulation across movement phases. By comparison, the control group showed nearly identical performance across all task conditions. These findings suggest that stroke involving the corticospinal system projection to the leg specifically impairs one or more components of the neural circuitry involved in lower extremity interlimb coordination. The express susceptibility of the antiphase pattern to exaggerated motor deficits could contribute to functional deficits in a number of antiphase leg movement tasks, including walking. PMID:20463199

  4. Muscle strategies for leg extensions on a "Reformer" apparatus.

    Science.gov (United States)

    Cantergi, Débora; Loss, Jefferson Fagundes; Jinha, Azim; Brodt, Guilherme Auler; Herzog, Walter

    2015-04-01

    Considering the kinematics of leg extensions performed on a Reformer apparatus, one would expect high activation of hip and knee extensor muscle groups. However, because of the bi-articular nature of some lower limb muscles, and the possibility to vary the direction of force application on the Reformer bar, muscles can be coordinated theoretically in a variety of ways and still achieve the desired outcome. Hence, the aim of this study was to determine the knee and hip moments during leg extensions performed on the Reformer apparatus and to estimate the forces in individual muscles crossing these joints using static optimization. Fifteen subjects performed leg extensions exercises on the Reformer apparatus using an individually chosen resistance. To our big surprise, we found that subjects performed the exercise using two conceptually different strategies (i) the first group used simultaneous hip and knee extension moments, (ii) while the second group used simultaneous hip flexion and knee extension moments to perform the exercise. These different strategies were achieved by changing the direction of the resultant force applied by the subject's feet on the Reformer bar. While leg extensions on the Reformer apparatus have been thought to strengthen the hip and knee extensors muscles, our results demonstrate that patients can perform the exercise in a different and unexpected way. In order to control the hip and knee moments and achieve the desired outcome of the exercise, the direction of force application on the Reformer bar must be controlled carefully.

  5. Acute effect of static stretching on power output during concentric dynamic constant external resistance leg extension.

    Science.gov (United States)

    Yamaguchi, Taichi; Ishii, Kojiro; Yamanaka, Masanori; Yasuda, Kazunori

    2006-11-01

    The purpose of the present study was to clarify the effect of static stretching on muscular performance during concentric isotonic (dynamic constant external resistance [DCER]) muscle actions under various loads. Concentric DCER leg extension power outputs were assessed in 12 healthy male subjects after 2 types of pretreatment. The pretreatments included (a) static stretching treatment performing 6 types of static stretching on leg extensors (4 sets of 30 seconds each with 20-second rest periods; total duration 20 minutes) and (b) nonstretching treatment by resting for 20 minutes in a sitting position. Loads during assessment of the power output were set to 5, 30, and 60% of the maximum voluntary contractile (MVC) torque with isometric leg extension in each subject. The peak power output following the static stretching treatment was significantly (p extensive static stretching significantly reduces power output with concentric DCER muscle actions under various loads. Common power activities are carried out by DCER muscle actions under various loads. Therefore, the result of the present study suggests that relatively extensive static stretching decreases power performance.

  6. Pedicled fillet of leg flap for extensive pressure sore coverage.

    Science.gov (United States)

    Jandali, Shareef; Low, David W

    2009-10-27

    Multiple large decubitus ulcers present a reconstructive challenge to the plastic surgeon. When stage IV pressure sores become recurrent or extensive, traditional flaps either have already been exhausted or would not be sufficient to cover the defect. A retrospective review was performed on all paraplegic patients who had chronic, extensive, and stage IV decubitus ulcers, and underwent reconstruction using a pedicled continuous musculocutaneous flap of the entire leg between 1998 and 2007. The extent and size of the debrided pressure sores, number of previous flap reconstructions, intraoperative blood loss, postoperative complications, and years of follow-up were all recorded. A description of the operative technique is also given. Four patients underwent a total leg fillet flap in the study period, with follow-up ranging from 2 to 7 years. Indications included extensive and bilateral trochanteric, sacral, and ischial pressure sores. Complications included intraoperative blood loss and postoperative heterotopic calcification. The total leg fillet flap is a very large and robust flap that offers paraplegic patients coverage of extensive stage IV pressure sores of the trochanteric, sacral, and ischial areas.

  7. Evidence of residual force enhancement for multi-joint leg extension.

    Science.gov (United States)

    Hahn, Daniel; Seiberl, Wolfgang; Schmidt, Susanne; Schweizer, Katrin; Schwirtz, Ansgar

    2010-05-28

    Force enhancement is a well accepted property of skeletal muscle and has been observed at all structural levels ranging from single myofibrils to voluntarily activated m. quadriceps femoris in vivo. However, force enhancement has not been studied for multi-joint movements like human leg extension; therefore knowledge about its relevance in daily living remains limited. The purpose of this study was to determine whether there is force enhancement during maximal voluntary multi-joint leg extension. Human leg extension was studied (n=22) on a motor driven leg press dynamometer where external reaction forces under the feet as well as activity of 8 lower extremity muscles were measured. In addition, torque in the ankle and knee joints was calculated using inverse dynamics. The steady-state isometric force, joint torques, and muscle activation after active stretch (20 degrees stretch amplitude at 60 degrees/s) were compared with the corresponding values obtained during isometric reference contractions. There was consistent force enhancement during and following stretch for both forces and joint torques. Potentiation during stretch reached values between 26% and 30%, while a significant force enhancement of 10.5-12.3% and 4.3-7.4% remained 0.5-1 and 2.5-3s after stretch, respectively. During stretch, EMG signals of m. gastrocnemius medialis and lateralis were significantly increased, while following stretch all analyzed muscles showed the same activity as during the reference contractions. We conclude from these results that force enhancement exists in everyday movements and should be accounted for when analyzing or modelling human movement.

  8. Knee and ankle joint torque-angle relationships of multi-joint leg extension.

    Science.gov (United States)

    Hahn, Daniel; Olvermann, Matthias; Richtberg, Jan; Seiberl, Wolfgang; Schwirtz, Ansgar

    2011-07-28

    The force-length-relation (F-l-r) is an important property of skeletal muscle to characterise its function, whereas for in vivo human muscles, torque-angle relationships (T-a-r) represent the maximum muscular capacity as a function of joint angle. However, since in vivo force/torque-length data is only available for rotational single-joint movements the purpose of the present study was to identify torque-angle-relationships for multi-joint leg extension. Therefore, inverse dynamics served for calculation of ankle and knee joint torques of 18 male subjects when performing maximum voluntary isometric contractions in a seated leg press. Measurements in increments of 10° knee angle from 30° to 100° knee flexion resulted in eight discrete angle configurations of hip, knee and ankle joints. For the knee joint we found an ascending-descending T-a-r with a maximum torque of 289.5° ± 43.3 Nm, which closely matches literature data from rotational knee extension. In comparison to literature we observed a shift of optimum knee angle towards knee extension. In contrast, the T-a-r of the ankle joint vastly differed from relationships obtained for isolated plantar flexion. For the ankle T-a-r derived from multi-joint leg extension subjects operated over different sections of the force-length curve, but the ankle T-a-r derived from isolated joint efforts was over the ascending limb for all subjects. Moreover, mean maximum torque of 234.7 ± 56.6 Nm exceeded maximal strength of isolated plantar flexion (185.7 ± 27.8 Nm). From these findings we conclude that muscle function between isolated and more physiological multi-joint tasks differs. This should be considered for ergonomic and sports optimisation as well as for modelling and simulation of human movement.

  9. The Effects of Hamstring Stretching on Leg Rotation during Knee Extension.

    Science.gov (United States)

    Kimura, Atsushi

    2013-06-01

    [Purpose] This study investigated the effects of hamstring stretching on leg rotation during active knee extension. [Subjects] Subjects were 100 bilateral legs of 50 healthy women without articular disease. [Methods] Hamstring hardness, leg rotation and muscle activities of the knee extensors during active knee extension were measured before and after hamstring stretching. [Results] Hamstring hardness was significantly decreased after hamstring stretching. The leg rotation angle, variation in leg rotation angle, variation in leg external rotation angle, and muscle activities of the vastus lateralis and rectus femoris were significantly increased after hamstring stretching. A moderate positive correlation was found between variation in leg rotation and variation in muscle hardness in hamstring. [Conclusion] Leg rotation during active knee extension was increased by hamstring stretching. Hamstring stretching would be effective as a pretreatment for restoring proper leg rotation when knee extension is conducted as a therapeutic exercise.

  10. Analysis of Interrelationships among Voluntary and Prosthetic Leg Joint Parameters Using Cyclograms

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    Nur Azah Hamzaid

    2017-04-01

    Full Text Available The walking mechanism of a prosthetic leg user is a tightly coordinated movement of several joints and limb segments. The interaction among the voluntary and mechanical joints and segments requires particular biomechanical insight. This study aims to analyze the inter-relationship between amputees' voluntary and mechanical coupled leg joints variables using cyclograms. From this analysis, the critical gait parameters in each gait phase were determined and analyzed if they contribute to a better powered prosthetic knee control design. To develop the cyclogram model, 20 healthy able-bodied subjects and 25 prosthesis and orthosis users (10 transtibial amputees, 5 transfemoral amputees, and 10 different pathological profiles of orthosis users walked at their comfortable speed in a 3D motion analysis lab setting. The gait parameters (i.e., angle, moment and power for the ankle, knee and hip joints were coupled to form 36 cyclograms relationship. The model was validated by quantifying the gait disparities of all the pathological walking by analyzing each cyclograms pairs using feed-forward neural network with backpropagation. Subsequently, the cyclogram pairs that contributed to the highest gait disparity of each gait phase were manipulated by replacing it with normal values and re-analyzed. The manipulated cyclograms relationship that showed highest improvement in terms of gait disparity calculation suggested that they are the most dominant parameters in powered-knee control. In case of transfemoral amputee walking, it was identified using this approach that at each gait sub-phase, the knee variables most responsible for closest to normal walking were: knee power during loading response and mid-stance, knee moment and knee angle during terminal stance phase, knee angle and knee power during pre-swing, knee angle at initial swing, and knee power at terminal swing. No variable was dominant during mid-swing phase implying natural pendulum effect of the

  11. Hydraulic leg extension is not necessarily the main drive in large spiders.

    Science.gov (United States)

    Weihmann, Tom; Günther, Michael; Blickhan, Reinhard

    2012-02-15

    Unlike most other arthropods, spiders have no extensor muscles in major leg joints. Therefore, hydraulic pressure generated in the prosoma provides leg extension. For decades, this mechanism was held responsible for the generation of the majority of the ground reaction forces, particularly in the hind legs. During propulsion, the front leg pairs must shorten whereas the hind legs have to be extended. Assuming that hind legs are essentially driven by hydraulics, their force vectors must pass the leg joints ventrally. However, at least in accelerated escape manoeuvres, we show here for the large cursorial spider species Ancylometes concolor that these force vectors, when projected into the leg plane, pass all leg joints dorsally. This indicates a reduced impact of the hydraulic mechanism on the generation of ground reaction forces. Although hydraulic leg extension still modulates their direction, the observed steep force vectors at the hind legs indicate a strong activity of flexors in the proximal joint complex that push the legs against the substrate. Consequently, the muscular mechanisms are dominant at least in the hind legs of large spiders.

  12. Brain-imaging during an isometric leg extension task at graded intensities

    Directory of Open Access Journals (Sweden)

    Vera eAbeln

    2013-10-01

    Full Text Available Imaging the brain during complex and intensive movements is challenging due to the susceptibility of brain-imaging methods for motion and myogenic artifacts. A few studies measured brain activity during either single-joint or low-intensity exercises; however, the cortical activation state during larger movements with increases up to maximal intensity has barely been investigated so far. Eleven right-handed volunteers (22-45 years in age performed isometric leg extensions with their right leg at 20%, 40%, 60%, 80% and 100% of their maximal voluntary contraction. Contractions were hold for 20 seconds respectively. Electroencephalographic (EEG and electromyographic (EMG activity was recorded. Standardized low-resolution brain electromagnetic tomography (sLORETA was used to localize the cortical current density within the premotor (PMC, primary motor (M1, primary somatosensory (S1 and somatosensory association cortex (SAC. ANOVA was used for repeated measures for comparison of intensities and between the left and right hemispheres.The quality of the EEG signal was satisfying up to 80% intensity. At 100% half of the participants were not able to keep their neck and face muscles relaxed, leading to myogenic artifacts. Higher contralateral versus ipsilateral hemispheric activity was found for the S1, SAC and PMC. M1 possessed higher ipsilateral activity. The highest activity was localized in the M1, followed by S1, PMC and SAC. EMG activity and cortical current density within the M1 increased with exercise intensity. EEG recordings during bigger movements up to submaximal intensity (80% are possible, but maximal intensities are still hard to investigate when subjects contracted their neck and face muscles at the same time. Isometric contractions mainly involve the M1, whereas the S1, PMC and SAC seem not to be involved in the force output. Limitations and recommendations for future studies are discussed.

  13. Brain-imaging during an isometric leg extension task at graded intensities.

    Science.gov (United States)

    Abeln, Vera; Harig, Alexandra; Knicker, Axel; Vogt, Tobias; Schneider, Stefan

    2013-01-01

    Imaging the brain during complex and intensive movements is challenging due to the susceptibility of brain-imaging methods for motion and myogenic artifacts. A few studies measured brain activity during either single-joint or low-intensity exercises; however, the cortical activation state during larger movements with increases up to maximal intensity has barely been investigated so far. Eleven right-handed volunteers (22-45 years in age) performed isometric leg extensions with their right leg at 20, 40, 60, 80, and 100% of their maximal voluntary contraction. Contractions were hold for 20 s respectively. Electroencephalographic (EEG) and electromyographic (EMG) activity was recorded. Standardized low-resolution brain electromagnetic tomography (sLORETA) was used to localize the cortical current density within the premotor (PMC), primary motor (M1), primary somatosensory (S1) and somatosensory association cortex (SAC). ANOVA was used for repeated measures for comparison of intensities and between the left and right hemispheres. The quality of the EEG signal was satisfying up to 80% intensity. At 100% half of the participants were not able to keep their neck and face muscles relaxed, leading to myogenic artifacts. Higher contralateral vs. ipsilateral hemispheric activity was found for the S1, SAC and, PMC. M1 possessed higher ipsilateral activity. The highest activity was localized in the M1, followed by S1, PMC, and SAC. EMG activity and cortical current density within the M1 increased with exercise intensity. EEG recordings during bigger movements up to submaximal intensity (80%) are possible, but maximal intensities are still hard to investigate when subjects contracted their neck and face muscles at the same time. Isometric contractions mainly involve the M1, whereas the S1, PMC, and SAC seem not to be involved in the force output. Limitations and recommendations for future studies are discussed.

  14. Acute effects of dynamic stretching exercise on power output during concentric dynamic constant external resistance leg extension.

    Science.gov (United States)

    Yamaguchi, Taichi; Ishii, Kojiro; Yamanaka, Masanori; Yasuda, Kazunori

    2007-11-01

    The purpose of the present study was to clarify the acute effect of dynamic stretching exercise on muscular performance during concentric dynamic constant external resistance (DCER, formally called isotonic) muscle actions under various loads. Concentric DCER leg extension power outputs were measured in 12 healthy male students after 2 types of pretreatment. The pretreatments were: (a) dynamic stretching treatment including 2 types of dynamic stretching exercises of leg extensors and the other 2 types of dynamic stretching exercises simulating the leg extension motion (2 sets of 15 times each with 30-second rest periods between sets; total duration: about 8 minutes), and (b) nonstretching treatment by resting for 8 minutes in a sitting position. Loads during measurement of the power output were set to 5, 30, and 60% of the maximum voluntary contractile (MVC) torque with isometric leg extension in each subject. The power output after the dynamic stretching treatment was significantly (p after the nonstretching treatment under each load (5% MVC: 468.4 +/- 102.6 W vs. 430.1 +/- 73.0 W; 30% MVC: 520.4 +/- 108.5 W vs. 491.0 +/- 93.0 W; 60% MVC: 487.1 +/- 100.6 W vs. 450.8 +/- 83.7 W). The present study demonstrated that dynamic stretching routines, such as dynamic stretching exercise of target muscle groups and dynamic stretching exercise simulating the actual motion pattern, significantly improve power output with concentric DCER muscle actions under various loads. These results suggested that dynamic stretching routines in warm-up protocols enhance power performance because common power activities are carried out by DCER muscle actions under various loads.

  15. Effects of static stretching for 30 seconds and dynamic stretching on leg extension power.

    Science.gov (United States)

    Yamaguchi, Taichi; Ishii, Kojiro

    2005-08-01

    The purposes of this study were to clarify the effects of static stretching for 30 seconds and dynamic stretching on leg extension power. Eleven healthy male students took part in this study. Each subject performed static stretching and dynamic stretching on the 5 muscle groups in the lower limbs and nonstretching on separate days. Leg extension power was measured before and after the static stretching, dynamic stretching, and nonstretching. No significant difference was found between leg extension power after static stretching (1788.5 +/- 85.7 W) and that after nonstretching (1784.8 +/- 108.4 W). On the other hand, leg extension power after dynamic stretching (2022.3 +/- 121.0 W) was significantly (p < 0.01) greater than that after nonstretching. These results suggest that static stretching for 30 seconds neither improves nor reduces muscular performance and that dynamic stretching enhances muscular performance.

  16. Differential glucose uptake in quadriceps and other leg muscles during one-legged dynamic submaximal knee-extension exercise

    DEFF Research Database (Denmark)

    Kalliokoski, Kari K; Boushel, Robert; Langberg, Henning;

    2011-01-01

    One-legged dynamic knee-extension exercise (DKE) is a widely used model to study the local cardiovascular and metabolic responses to exercise of the quadriceps muscles. In this study, we explored the extent to which different muscles of the quadriceps are activated during exercise using positron...... in the vastus intermedius (VI) and lowest in the vastus lateralis (VL; VI vs VL, p muscles in the exercising leg was 35 ± 9%. Compared...... to mean GU in QF (=100%), GU was on average 73% in VL, 84% in rectus femoris, 115% in vastus medialis, and 142% in VI. Variable activation of hamstring muscles and muscles of the lower leg was also observed. These results show that GU of different muscles of quadriceps muscle group as well as between...

  17. Differential glucose uptake in quadriceps and other leg muscles during one-legged dynamic submaximal knee-extension exercise

    Directory of Open Access Journals (Sweden)

    Kari eKalliokoski

    2011-10-01

    Full Text Available One-legged dynamic knee-extension exercise (DKE is a widely used model to study the local cardiovascular and metabolic responses to exercise of the quadriceps muscles. In this study, we explored the extent to which different muscles of the quadriceps are activated during exercise using positron emission tomography (PET determined uptake of [18F]-fluoro-deoxy-glucose (GU during DKE. Five healthy male subjects performed DKE at 25 W for 35 min and both the contracting and contralateral resting leg were scanned with PET from mid-thigh and distally. On average, exercise GU was the highest in the vastus intermedius (VI and lowest in the vastus lateralis (VL (VI vs VL, p<0.05, whereas the coefficient of variation was highest in VL (VL vs VI, p<0.05. Coefficient of variation between the mean values of the four QF muscles in the exercising leg was 35±9%. Compared to mean GU in QF (=100%, GU was on average 73% in VL, 84% in rectus femoris, 115% in vastus medialis, and 142% in VI. Variable activation of hamstring muscles and muscles of the lower leg was also observed. These results show that GU of different muscles of quadriceps muscle group as well as between individuals vary greatly during DKE, and suggests that muscle activity is not equal between quadriceps muscles in this exercise model. Furthermore, posterior thigh muscles and lower leg muscles are more active than hitherto thought even during this moderate exercise intensity.

  18. Differential glucose uptake in quadriceps and other leg muscles during one-legged dynamic submaximal knee-extension exercise.

    Science.gov (United States)

    Kalliokoski, Kari K; Boushel, Robert; Langberg, Henning; Scheede-Bergdahl, Celena; Ryberg, Ann Kathrine; Døssing, Simon; Kjær, Andreas; Kjær, Michael

    2011-01-01

    One-legged dynamic knee-extension exercise (DKE) is a widely used model to study the local cardiovascular and metabolic responses to exercise of the quadriceps muscles. In this study, we explored the extent to which different muscles of the quadriceps are activated during exercise using positron emission tomography (PET) determined uptake of [(18)F]-fluoro-deoxy-glucose (GU) during DKE. Five healthy male subjects performed DKE at 25 W for 35 min and both the contracting and contralateral resting leg were scanned with PET from mid-thigh and distally. On average, exercise GU was the highest in the vastus intermedius (VI) and lowest in the vastus lateralis (VL; VI vs VL, p muscles in the exercising leg was 35 ± 9%. Compared to mean GU in QF (=100%), GU was on average 73% in VL, 84% in rectus femoris, 115% in vastus medialis, and 142% in VI. Variable activation of hamstring muscles and muscles of the lower leg was also observed. These results show that GU of different muscles of quadriceps muscle group as well as between individuals vary greatly during DKE, and suggests that muscle activity is not equal between quadriceps muscles in this exercise model. Furthermore, posterior thigh muscles and lower leg muscles are more active than hitherto thought even during this moderate exercise intensity.

  19. Leg-extension strength and chair-rise performance in elderly women with Parkinson's disease.

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    Pääsuke, Mati; Ereline, Jaan; Gapeyeva, Helena; Joost, Kadri; Mõttus, Karin; Taba, Pille

    2004-10-01

    The lower extremity performance in elderly female patients with mild to moderate Parkinson's disease (PD; n = 12) and controls (n = 16) was compared. Isometric dynamometry and force-plate measurements were used. PD patients had lower (p leg-extension force (MF), BL isometric MF relative to body mass, and maximal rate of isometric force development than control participants. BL strength deficit was greater (p leg-extensor muscles. Reduced BL leg-extension strength might contribute to the difficulty of individuals with PD to rise from a chair.

  20. Differential glucose uptake in quadriceps and other leg muscles during one-legged dynamic submaximal knee-extension exercise

    OpenAIRE

    Kari eKalliokoski; Robert eBoushel; Henning eLangberg; Celena eScheede-Bergdahl; Ann Kathrine Ryberg; Simon eDoessing; Andreas eKjaer; Michael eKjaer

    2011-01-01

    One-legged dynamic knee-extension exercise (DKE) is a widely used model to study the local cardiovascular and metabolic responses to exercise of the quadriceps muscles. In this study, we explored the extent to which different muscles of the quadriceps are activated during exercise using positron emission tomography (PET) determined uptake of [18F]-fluoro-deoxy-glucose (GU) during DKE. Five healthy male subjects performed DKE at 25 W for 35 min and both the contracting and contralateral resti...

  1. Differential glucose uptake in quadriceps and other leg muscles during one-legged dynamic submaximal knee-extension exercise

    OpenAIRE

    Kari eKalliokoski; Robert eBoushel; Henning eLangberg; Celena eScheede-Bergdahl; Ann Kathrine Ryberg; Simon eDoessing; Andreas eKjaer; Michael eKjaer

    2011-01-01

    One-legged dynamic knee-extension exercise (DKE) is a widely used model to study the local cardiovascular and metabolic responses to exercise of the quadriceps muscles. In this study, we explored the extent to which different muscles of the quadriceps are activated during exercise using positron emission tomography (PET) determined uptake of [18F]-fluoro-deoxy-glucose (GU) during DKE. Five healthy male subjects performed DKE at 25 W for 35 min and both the contracting and contralateral resti...

  2. Bilateral leg extension power and fat-free mass in young oarsmen.

    Science.gov (United States)

    Yoshiga, Chie C; Higuchi, Mitsuru

    2003-11-01

    We evaluated the impact of bilateral leg extension power and fat-free mass on 2000 m rowing ergometer performance in 332 young oarsmen (age 21+/-2 years, height 1.76+/-0.05 m, body mass 62+/-6 kg; mean+/-s). The 2000 m rowing performance time was correlated with height (1.62-1.93 m; R2=0.23, Pleg extension power (1202-3302 W; R2=0.38, Pleg extension power as regressor variables. Fat-free mass explained 58% of the variability in rowing performance and the inclusion of bilateral leg extension power improved the power of prediction by 5%. The results suggest that rowing involves almost every muscle in the body and that bilateral leg extension power is very important during this activity.

  3. Extension and customization of self-stability control in compliant legged systems.

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    Ernst, M; Geyer, H; Blickhan, R

    2012-12-01

    Several recent studies on the control of legged locomotion in animal and robot running focus on the influence of different leg parameters on gait stability. In a preceding investigation self-stability controls showing deadbeat behavior could be obtained by studying the dynamics of the system in dependence of the leg orientation carefully adjusted during the flight phase. Such controls allow to accommodate disturbances of the ground level without having to detect them. Here we further this method in two ways. Besides the leg orientation, we allow changes in leg stiffness during flight and show that this extension substantially improves the rejection of ground disturbances. In a human like example the tolerance of random variation in ground level over many steps increased from 3.5% to 35% of leg length. In single steps changes of about 70% leg length (either up or down) could be negotiated. The variable leg stiffness not only allows to start with flat leg orientations maximizing step tolerances but also increase the control subspace. This allows to customize self-stability controls and to consider physical and technical limitations found in animals and robots.

  4. Differential Glucose Uptake in Quadriceps and Other Leg Muscles During One-Legged Dynamic Submaximal Knee-Extension Exercise

    OpenAIRE

    Kalliokoski, Kari K.; Boushel, Robert; Langberg, Henning; Scheede-Bergdahl, Celena; Ryberg, Ann Kathrine; Døssing, Simon; Kjær, Andreas; Kjær, Michael

    2011-01-01

    One-legged dynamic knee-extension exercise (DKE) is a widely used model to study the local cardiovascular and metabolic responses to exercise of the quadriceps muscles. In this study, we explored the extent to which different muscles of the quadriceps are activated during exercise using positron emission tomography (PET) determined uptake of [18F]-fluoro-deoxy-glucose (GU) during DKE. Five healthy male subjects performed DKE at 25 W for 35 min and both the contracting and contralateral restin...

  5. Leg extension power deficit and mobility limitation in women recovering from hip fracture.

    Science.gov (United States)

    Portegijs, Erja; Sipilä, Sarianna; Rantanen, Taina; Lamb, Sarah E

    2008-05-01

    After hip fracture, muscle strength and power remain persistently poor, especially in the fractured leg. This study explores whether asymmetrical leg extension power (LEP) deficit affects mobility in women after proximal femoral fracture (PFF). In this observational study, LEP of both legs, 10- and 50-foot walking speed, and stair-climbing speed were measured in 43 women, aged 73-96, at 1 and 13 wks after surgical repair of PFF. Asymmetrical LEP deficit was calculated as (fractured/(sum both legs)) x 100%. Between weeks 1 and 13 after PFF surgery, LEP increased in the fractured and nonfractured legs by 100% and 30%, respectively. Asymmetrical deficit was reduced from 28.5 +/- 10.2% to 40.4 +/- 8.6%. Linear regression analyses showed that poorer LEP of the nonfractured leg at week 1 correlated significantly with slower walking (beta > 0.525, P stair-climbing speed (beta > 0.349, P 0.354, P stair-climbing speed (beta > 0.343, P walking speed. Higher LEP of the nonfractured leg predicted better recovery of mobility after PFF. Larger asymmetrical LEP deficit correlated with limitation in climbing stairs-a more challenging mobility task where fluent performance requires unilateral force production.

  6. Isokinetic Leg Flexion and Extension Strength of Elite Adolescent Female Track and Field Athletes.

    Science.gov (United States)

    Housh, Terry J.; And Others

    1984-01-01

    Adolescent female track-and-field athletes were measured to compare isokinetic strength of leg flexion and extension movements. Throwers, jumpers, middle-distance runners, and sprinters participated in the study. Throwers were found to be stronger in absolute strength, but there were no significant differences in relative strength. Results are…

  7. Perceived exertion is related to muscle activity during leg extension exercise.

    Science.gov (United States)

    Duncan, Michael J; Al-Nakeeb, Yahya; Scurr, Joanna

    2006-01-01

    This study examined the relationship between ratings of perceived exertion and muscle activity during dynamic leg extension exercise using a resistance exercise specific OMNI-RPE scale. Twenty volunteers (10 males, 10 females, age 22.2 +/- 3.1 yr) performed one set of leg extension exercise at 30%, 60%, and 90% of their one-repetition maximum (1-RM). OMNI-RPE responses were assessed for both the active muscle (OMNI-AM) and the overall body (OMNI-O) following each intensity. Electromyography (EMG) data were collected from the rectus femoris, vastus lateralis, and vastus medialis muscles. A two-factor repeated measures ANOVA showed a significant OMNI-RPE (region) X intensity interaction (p muscle groups (all p Muscle activity was significantly and positively related to OMNI-RPE in both the active muscle and overall body (all p < 0.01). The OMNI-Res RPE scale may be a promising technique for regulating resistance training intensity.

  8. Normalized knee-extension strength or leg-press power after fast-track total knee arthroplasty

    DEFF Research Database (Denmark)

    Aalund, Peter K; Larsen, Kristian; Hansen, Torben Bæk

    2013-01-01

    and dynamic leg presses to determine their body-mass normalized knee extension strength and leg press power, respectively. The 10-m fast speed walking and 30-s chair stand tests were used to determine performance-based function, while the Western Ontario McMaster University Osteoarthritis Index (WOMAC...

  9. Chronic ulceration of the leg following extensive scarring due to a snake bite complicated by squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Mello, L.F.B.; Barcelos, M.G.; Nogueira Neto, N.C. [Dept. of Radiology, National Cancer Institute - INCA, Rio de Janeiro, RJ (Brazil); Meohas, W. [Dept. of Surgery (Bone and Soft Tissue), National Cancer Institute - INCA, Rio de Janeiro, RJ (Brazil); Pinto, L.W. [Department of Surgical Pathology, National Cancer Institute - INCA, Rio de Janeiro, RJ (Brazil); Melo, P.A. [Pharmacology Lab. of Snake-related Toxins, Department of Basic and Clinical Pharmacology, Federal University of Rio de Janeiro - UFRJ, Rio de Janeiro, RJ (Brazil); Smith, J. [Dept. of Radiology, National Cancer Institute - INCA, Rio de Janeiro, RJ (Brazil); Rua Humberto de Campos 974/1301, Leblon 22430 - 190, Rio de Janeiro, RJ (Brazil)

    2000-05-01

    Chronic ulcers of the leg are common in Brazil, perhaps more common than in the developed world. We report a case of a chronic ulcer of the leg following extensive scarring due to a bite by a venomous snake, which eventually led to a squamous cell carcinoma. (orig.)

  10. Effect of stochastic modulation of inter-pulse interval during stimulated isokinetic leg extension

    Directory of Open Access Journals (Sweden)

    Efe Anil Aksöz

    2016-07-01

    Full Text Available Recumbent cycling exercise achieved by functional electrical stimulation (FES of the paralyzed leg muscles is effective for cardiopulmonary and musculoskeletal conditioning after spinal cord injury, but its full potential has not yet been realized. Mechanical power output and efficiency is very low and endurance is limited due to early onset of muscle fatigue. The aim of this work was to compare stochastic modulation of the inter-pulse interval (IPI to constant-frequency stimulation during an isokinetic leg extension task similar to FES-cycling. Seven able-bodied subjects participated: both quadriceps muscles were stimulated (n = 14 with two activation patterns (P1-constant frequency, P2-stochastic IPI. There was significantly higher power output with P2 during the first 30 s (p = 0.0092, the last 30 s (p = 0.018 and overall (p = 0.0057, but there was no overall effect on fatiguability when stimulation frequency was randomly modulated.

  11. Effect of Stochastic Modulation of Inter-Pulse Interval During Stimulated Isokinetic Leg Extension

    Science.gov (United States)

    Aksöz, Efe Anil; Laubacher, Marco; Binder-Macleod, Stuart; Hunt, Kenneth J.

    2016-01-01

    Recumbent cycling exercise achieved by functional electrical stimulation (FES) of the paralyzed leg muscles is effective for cardiopulmonary and musculoskeletal conditioning after spinal cord injury, but its full potential has not yet been realized. Mechanical power output and efficiency is very low and endurance is limited due to early onset of muscle fatigue. The aim of this work was to compare stochastic modulation of the inter-pulse interval (IPI) to constant-frequency stimulation during an isokinetic leg extension task similar to FES-cycling. Seven able-bodied subjects participated: both quadriceps muscles were stimulated (n = 14) with two activation patterns (P1-constant frequency, P2-stochastic IPI). There was significantly higher power output with P2 during the first 30 s (p = 0.0092), the last 30 s (p = 0.018) and overall (p = 0.0057), but there was no overall effect on fatiguability when stimulation frequency was randomly modulated. PMID:27990242

  12. Range of motion and leg rotation affect EMG activation levels of the superficial quadriceps muscles during leg extension.

    Science.gov (United States)

    Signorile, Joseph F; Lew, Karen; Stoutenberg, Mark; Pluchino, Alessandra; Lewis, John E; Gao, Jinrun

    2014-06-30

    The leg extension (LE) is commonly used to strengthen the quadriceps muscles during training and rehabilitation. This study examined the effects of limb position (POS) and range of motion (ROM) on quadriceps electromyography (EMG) during 8 repetitions (REP) of LE. Twenty-four participants performed eight LE REP at their 8-repetition maximum with lower limbs medially rotated (TI), laterally rotated (TO), and neutral (NEU). Each REP EMG was averaged over the first, middle, and final 0.524 rad ROM. For vastus medialis oblique (VMO), a REP x ROM interaction was detected (p<0.02). The middle 0.524 rad produced significantly higher EMG than the initial 0.524 rad for REP 6-8 and the final 0.524 rad produced higher EMG than the initial 0.524 rad for REP 1, 2, 3, 4, 6, 8 (p<0.05). For rectus femoris (RF), EMG activity increased across REP with TO generating the greatest activity (p<0.001). For vastus lateralis (VL), EMG increased across REP (p<0.001) with NEU and TO EMG increasing linearly throughout ROM, and TI activity greatest during the middle 0.524 rad. We conclude that to target the VMO the optimal ROM is the final 1.047 rad regardless of POS, while maximum EMG for the RF is generated using TO regardless of ROM. In contrast, the VL is maximally activated using TI over the first 1.047 rad ROM or in NEU over the final 0.524 rad ROM.

  13. Range of motion and leg rotation affect electromyography activation levels of the superficial quadriceps muscles during leg extension.

    Science.gov (United States)

    Signorile, Joseph F; Lew, Karen M; Stoutenberg, Mark; Pluchino, Alessandra; Lewis, John E; Gao, Jinrun

    2014-09-01

    Leg extension (LE) is commonly used to strengthen the quadriceps muscles during training and rehabilitation. This study examined the effects of limb position (POS) and range of motion (ROM) on quadriceps electromyography (EMG) during 8 repetitions (REP) of LE. Twenty-four participants performed 8 LE REP at their 8 repetition maximum with lower limbs medially rotated (TI), laterally rotated (TO), and neutral (NEU). Each REP EMG was averaged over the first, middle, and final 0.524 rad ROM. For vastus medialis oblique (VMO), a REP × ROM interaction was detected (p < 0.02). The middle 0.524 rad produced significantly higher EMG than the initial 0.524 rad for REP 6-8 and the final 0.524 rad produced higher EMG than the initial 0.524 rad for REP 1, 2, 3, 4, 6, and 8 (p ≤ 0.05). For rectus femoris (RF), EMG activity increased across REP with TO generating the greatest activity (p < 0.001). For vastus lateralis (VL), EMG increased across REP (p < 0.001) with NEU and TO EMG increasing linearly throughout ROM and TI activity greatest during the middle 0.524 rad. We conclude that to target the VMO, the optimal ROM is the final 1.047 rad regardless of POS, while maximum EMG for the RF is generated using TO regardless of ROM. In contrast, the VL is maximally activated using TI over the first 1.047 rad ROM or in NEU over the final 0.524 rad ROM.

  14. Acute effects of dynamic stretching exercise on power output during concentric dynamic constant external resistance leg extension

    OpenAIRE

    YAMAGUCHI, TAICHI; Ishii, Kojiro; Yamanaka, Masanori; YASUDA, KAZUNORI

    2007-01-01

    AbstractThe purpose of the present study was to clarify the acute effect of dynamic stretching exercise on muscular performance during concentric dynamic constant external resistance (DCER, formally called isotonic) muscle actions under various loads. Concentric DCER leg extension power outputs were measured in 12 healthy male students after 2 types of pretreatment. The pre- treatments were: (a) dynamic stretching treatment including 2 types of dynamic stretching exercises of leg extensors an...

  15. The impact of foot position on electromyographical activity of the superficial quadriceps muscles during leg extension.

    Science.gov (United States)

    Stoutenberg, Mark; Pluchino, Alessandra P; Ma, Fangchao; Hoctor, Jennifer E; Signorile, Joseph F

    2005-11-01

    This study investigated variations in electromyographic (EMG) responses of the vastus lateralis (VL), rectus femoris (RF), and vastus medialis (VM) due to foot position during leg extension. Twenty-four men and women (23.67 +/= 4.02 years) performed 8 repetitions at 70% of 8 repetition maximum with their leg medially rotated, laterally rotated, and neutral. Repeated-measures analyses of variance indicated that the highest normalized root mean square (NrmsEMG) for the VM and VL occurred with medial rotation, and the highest NrmsEMG for the RF occurred with lateral rotation. Significant NrmsEMG increases and median power frequency decreases occurred across repetitions regardless of foot position. Therefore, medial rotation produced the greatest muscle activation for the VL and VM, whereas lateral rotation produced the greatest activation in the RF. These findings are applicable to athletes or bodybuilders who are seeking to selectively increase either the size or performance of a specific muscle of the quadriceps group.

  16. Posture effects on spontaneous limb movements, alternated stepping, and the leg extension response in neonatal rats.

    Science.gov (United States)

    Mendez-Gallardo, Valerie; Roberto, Megan E; Kauer, Sierra D; Brumley, Michele R

    2016-03-01

    The development of postural control is considered an important factor for the expression of coordinated behavior such as locomotion. In the natural setting of the nest, newborn rat pups adapt their posture to perform behaviors of ecological relevance such as those related to suckling. The current study explores the role of posture in the expression of three behaviors in the newborn rat: spontaneous limb activity, locomotor-like stepping behavior, and the leg extension response (LER). One-day-old rat pups were tested in one of two postures--prone or supine--on each of these behavioral measures. Results showed that pups expressed more spontaneous activity while supine, more stepping while prone, and no differences in LER expression between the two postures. Together these findings show that posture affects the expression of newborn behavior patterns in different ways, and suggest that posture may act as a facilitator or a limiting factor in the expression of different behaviors during early development.

  17. Effect of leg support on muscle cross-correlation of bilateral erector spinae during trunk flexion-extension performance.

    Science.gov (United States)

    Shan, Xinhai; Wei, Yugang; Chen, Zhentao; Fan, Lixia; Shi, Weifei; Yang, Shulong

    2014-01-01

    Investigations corresponding to the affected factors of the cross-correlation of pair muscles are limited though muscle activation patterns of bilateral erector spinae (ES) during trunk flexion-extension performance in standing have been utilized as an indicator in the evaluation of low back pain condition. The purpose of the study is to evaluate the effect of leg support on the cross-correlation of bilateral ES, and to test if the average of bilateral ES could weaken this effect. Twenty male university students volunteered for this study. Each performed the trunk flexion-extension in three leg support conditions randomly with the condition of single left leg support, double leg support and single right leg support, respectively. Each condition included three trials of trunk flexion-extension with the cycle of 5s flexion and 5s extension in standing. Surface electromyography from the right ES muscle as well as from the left one was recorded. The cross-correlation both in pair muscle of right-left ES and in pair muscle of right-average of bilateral ES was calculated in the flexion as well as extension period. A one-way ANOVA with repeated measures was used. The results showed that leg support has some effect on cross-correlation of bilateral ES, which causes the absolute value of phase lag to be significantly larger in flexion period. It is suggested that this effect could be weakened by the average of bilateral ES through significantly increasing the cross-correlation coefficient, and decreasing the absolute value of phase lag.

  18. Sensorimotor training during expression of the leg extension response (LER) in 1-day-old rats.

    Science.gov (United States)

    Belnap, Starlie C; Allmond, Jacob T; Boomhower, Steven R; Roberto, Megan E; Brumley, Michele R

    2014-11-01

    In newborn rats, the leg extension response (LER) is a coordinated hyperextension of the hindlimbs that is shown in response to anogenital stimulation. Here we examined the influence of sensorimotor training on LER expression in postnatal day 1 rats. In Experiment 1, we examined if proprioceptive feedback facilitates LER expression. We did this by repeatedly stimulating the pup's anogenital region with a vibrotactile device, to experimentally evoke the LER, thus increasing LER-relevant hindlimb proprioceptive feedback during training. In trained subjects, the LER was evoked every 4 min for 15 trials, followed by a final LER test. Results indicated that proprioceptive feedback on its own did not alter later expression of the LER. In Experiment 2, we examined the effect of both proprioceptive and cutaneous feedback on LER expression, through the use of a range of motion (ROM) restriction during training. During ROM restriction, a Plexiglas plate was placed beneath the pup at 50% of limb length. After the 15th training trial, a final LER test occurred with no ROM restriction in place. Compared to controls, pups that experienced ROM restriction exhibited a significantly shorter LER duration, and smaller hip and ankle angles during the LER test (indicating greater limb flexion). Together these findings show that concurrent proprioceptive and cutaneous feedback, but not proprioceptive feedback alone, has persistent effects on expression of this newborn action pattern.

  19. Relationships between the extent of apnea-induced bradycardia and the vascular response in the arm and leg during dynamic two-legged knee extension exercise.

    Science.gov (United States)

    Nishiyasu, Takeshi; Tsukamoto, Rina; Kawai, Katsuhito; Hayashi, Keiji; Koga, Shunsaku; Ichinose, Masashi

    2012-02-01

    Our aim was to test the hypothesis that apnea-induced hemodynamic responses during dynamic exercise in humans differ between those who show strong bradycardia and those who show only mild bradycardia. After apnea-induced changes in heart rate (HR) were evaluated during dynamic exercise, 23 healthy subjects were selected and divided into a large response group (L group; n = 11) and a small response group (S group; n = 12). While subjects performed a two-legged dynamic knee extension exercise at a work load that increased HR by 30 beats/min, apnea-induced changes in HR, cardiac output (CO), mean arterial pressure (MAP), arterial O(2) saturation (Sa(O(2))), forearm blood flow (FBF), and leg blood flow (LBF) were measured. During apnea, HR in the L group (54 ± 2 beats/min) was lower than in the S group (92 ± 3 beats/min, P leg vascular conductance (LVC), and total vascular conductance (TVC) were all reduced, and MAP was increased in both groups, although the changes in CO, TVC, LBF, LVC, and MAP were larger in the L group than in the S group (P muscle regions.

  20. Tissue temperature transients in resting contra-lateral leg muscle tissue during isolated knee extension.

    Science.gov (United States)

    Kenny, Glen P; Reardon, Frank D; Ducharme, Michel B; Reardon, Mark L; Zaleski, Wytek

    2002-12-01

    This study was designed to evaluate the role of non-active tissue in the retention and dissipation of heat during and following intense isolated muscle activity. Six subjects performed an incremental isotonic test (constant angular velocity, increases in force output) on a KIN-COM isokinetic apparatus to determine their maximal oxygen consumption during single knee extensions (VO2sp). In a subsequent session, a thin wire multi-sensor temperature probe was inserted into the left vastus medialis under ultrasound guidance at a specific internal marker. The deepest temperature sensor (tip, Tmu10) was located approximately 10 mm from the femur and deep femoral artery with 2 additional sensors located at 15 (Tmu25) and 30 (Tmu40) mm from the tip. Implant site was midway between and medial to a line joining the anterior superior iliac spine and base of patella. Esophageal temperature (Tes) temperature was measured as an index of core temperature. Subjects rested in a supine position for 60 min followed by 30 min of seated rest in an ambient condition of 22 degree C. Subjects then performed 15 min of isolated single right knee extensions against a dynamic resistance on a KIN COM corresponding to 60% of VO2sp at 60 degree x sec(-1). Exercise was followed by 60 min of seated rest. Resting Tes was 37 degree C while Tmu10, Tmu25, and Tmu40 were 36.58, 36.55 and 36.45 degree C, respectively. Exercise resulted in a Tes increase of 0.31 C above pre-exercise resting. Tmu of the non-exercising leg increased 0.23, 0.19 and 0.09 degree C for Tmu10, Tmu25, and Tmu40, respectively. While Tes decreased to baseline values within approximately 15 min of end-exercise, Tmu10 reached resting values following approximately 40 min of recovery. These results suggest that during isolated muscle activity, convective heat transfer by the blood to non-active muscle tissue may have a significant role in maintaining resting core temperature.

  1. Investigation of jack-up leg extension for deep water operations

    Directory of Open Access Journals (Sweden)

    Yousri M.A. Welaya

    2015-03-01

    Full Text Available Since the first jack-up was built, jackups have become the most popular type of mobile offshore drilling unit (MODU for offshore exploration and development purposes in shallow water. The most pivotal component of the jack-up unit is the leg, which can directly affect the global performance of the unit. In this paper, an investigation into extending the length of the jack up leg is carried out in order to study the enhancement of the rig capability to drill in deeper water approaching the range of the Semisubmersible Drilling Unit (SSDU (300-1000ft. A study of the performance of a deep-water jack-up unit is performed with different leg lengths. Typical leg scantling dimensions and identical external loads are assigned, and then a detailed Finite Element Analysis (FEA model is created in order to simulate the jack-up leg unit’s structural behavior. A Multi-point Constraint (MPC element together with the spring element is used to deal with the boundary conditions. Finally, a comparative analysis for five leg lengths is carried out to illustrate their performance, including the ultimate static strength, and weight.

  2. Loading the limb during rhythmic leg movements lengthens the duration of both flexion and extension in human infants.

    Science.gov (United States)

    Musselman, Kristin E; Yang, Jaynie F

    2007-02-01

    Sensory input is critical for adapting motor outputs to meet environmental conditions. A ubiquitous force on all terrestrial animals is gravity. It is possible that when performing rhythmic movements, animals respond to load-related feedback in the same way by prolonging the muscle activity resisting the load. We hypothesized that for rhythmic leg movements, the period (extension or flexion) experiencing the higher load will be longer and vary more strongly with cycle period. Six rhythmic movements were studied in human infants (aged 3-10 mo), each providing different degrees of load-related feedback to the legs during flexion and extension of the limb. Kicking in supine provided similar loads (inertial) during flexion and extension. Stepping on a treadmill, kicking in supine against a foot-plate, and kicking in sitting loaded the legs during extension more than flexion, whereas air-stepping and air-stepping with ankle weights did the opposite. Video, electrogoniometry, surface electromyography, and contact forces were recorded. We showed that load-related feedback could make either the duration of flexion or extension longer. Within the tasks of stepping and kicking against a plate, infants who exerted lower forces showed shorter extensor durations than those who exerted higher forces. Because older babies tend to step with greater force, we wished to rule out the contribution of age. Eight babies (>8 mo old) were studied during stepping, in which we manipulated the amount of weight-bearing. The same effect of load was seen. Hence, the degree of loading directly affects the duration of extension in an incremental way.

  3. The effect of hypoxia on pulmonary O2 uptake, leg blood flow and muscle deoxygenation during single-leg knee-extension exercise.

    Science.gov (United States)

    DeLorey, Darren S; Shaw, Colin N; Shoemaker, J Kevin; Kowalchuk, John M; Paterson, Donald H

    2004-05-01

    The effect of hypoxic breathing on pulmonary O(2) uptake (VO(2p)), leg blood flow (LBF) and O(2) delivery and deoxygenation of the vastus lateralis muscle was examined during constant-load single-leg knee-extension exercise. Seven subjects (24 +/- 4 years; mean +/-s.d.) performed two transitions from unloaded to moderate-intensity exercise (21 W) under normoxic and hypoxic (P(ET)O(2)= 60 mmHg) conditions. Breath-by-breath VO(2p) and beat-by-beat femoral artery mean blood velocity (MBV) were measured by mass spectrometer and volume turbine and Doppler ultrasound (VingMed, CFM 750), respectively. Deoxy-(HHb), oxy-, and total haemoglobin/myoglobin were measured continuously by near-infrared spectroscopy (NIRS; Hamamatsu NIRO-300). VO(2p) data were filtered and averaged to 5 s bins at 20, 40, 60, 120, 180 and 300 s. MBV data were filtered and averaged to 2 s bins (1 contraction cycle). LBF was calculated for each contraction cycle and averaged to 5 s bins at 20, 40, 60, 120, 180 and 300 s. VO(2p) was significantly lower in hypoxia throughout the period of 20, 40, 60 and 120 s of the exercise on-transient. LBF (l min(-1)) was approximately 35% higher (P > 0.05) in hypoxia during the on-transient and steady-state of KE exercise, resulting in a similar leg O(2) delivery in hypoxia and normoxia. Local muscle deoxygenation (HHb) was similar in hypoxia and normoxia. These results suggest that factors other than O(2) delivery, possibly the diffusion of O(2,) were responsible for the lower O(2) uptake during the exercise on-transient in hypoxia.

  4. Pelvic movement strategies and leg extension power in patients with end-stage medial compartment knee osteoarthritis: a cross-sectional study.

    Science.gov (United States)

    Kierkegaard, Signe; Jørgensen, Peter Bo; Dalgas, Ulrik; Søballe, Kjeld; Mechlenburg, Inger

    2015-09-01

    During movement tasks, patients with medial compartment knee osteoarthritis use compensatory strategies to minimise the joint load of the affected leg. Movement strategies of the knees and trunk have been investigated, but less is known about movement strategies of the pelvis during advancing functional tasks, and how these strategies are associated with leg extension power. The aim of the study was to investigate pelvic movement strategies and leg extension power in patients with end-stage medial compartment knee osteoarthritis compared with controls. 57 patients (mean age 65.6 years) scheduled for medial uni-compartmental knee arthroplasty, and 29 age and gender matched controls were included in this cross-sectional study. Leg extension power was tested with the Nottingham Leg Extension Power-Rig. Pelvic range of motion was derived from an inertia-based measurement unit placed over the sacrum bone during walking, stair climbing and stepping. Patients had lower leg extension power than controls (20-39 %, P 0.06). Furthermore, an inverse association (coefficient: -0.03 to -0.04; R (2) = 13-22 %) between leg extension power and pelvic range of motion during stair and step descending was found in the patients. Compared to controls, patients with medial compartment knee osteoarthritis use greater pelvic movements during advanced functional performance tests, particularly when these involve descending tasks. Further studies should investigate if it is possible to alter these movement strategies by an intervention aimed at increasing strength and power for the patients.

  5. Within- and between-session reliability of the maximal voluntary knee extension torque and activation.

    Science.gov (United States)

    Park, Jihong; Hopkins, J Ty

    2013-01-01

    A ratio between the torque generated by maximal voluntary isometric contraction (MVIC) and exogenous electrical stimulus, central activation ratio (CAR), has been widely used to assess quadriceps function. To date, no data exist regarding between-session reliability of this measurement. Thirteen neurologically sound volunteers underwent three testing sessions (three trials per session) with 48 hours between-session. Subjects performed MVICs of the quadriceps with the knee locked at 90° flexion and the hip at 85°. Once the MVIC reached a plateau, an electrical stimulation from superimposed burst technique (SIB: 125 V with peak output current 450 mA) was manually delivered and transmitted directly to the quadriceps via stimulating electrodes. CAR was calculated by using the following equation: CAR = MVIC torque/MVIC + SIB torque. Intraclass correlation coefficients (ICC) were calculated within- (ICC((2,1))) and between-session (ICC((2,k))) for MVIC torques and CAR values. Our data show that quadriceps MVIC and CAR are very reliable both within- (ICC((2,1)) = 0.99 for MVIC; 0.94 for CAR) and between-measurement sessions (ICC((2,k)) = 0.92 for MVIC; 0.86 for CAR) in healthy young adults. For clinical research, more data of the patients with pathological conditions are required to ensure reproducibility of calculation of CAR.

  6. Quantification of reflex activity in stroke survivors during an imposed multi-joint leg extension movement.

    Science.gov (United States)

    Black, Iian; Nichols, Diane; Pelliccio, Marlena; Hidler, Joseph

    2007-11-01

    The goal of this study was to compare short- and long-latency reflex responses in eight major lower-extremity muscle groups following an imposed multi-joint leg movement between a group of 14 chronic (>1 year) stroke survivors and 10 healthy age-matched controls, and to investigate the influence of joint velocities and muscle excitation levels on these reflex responses in each respective group. Subjects were seated with their foot anchored to a sliding footplate that could extend their leg. Prior to the leg being moved, subjects were instructed to pre-activate hip and knee flexors and extensors. Feedback of joint torque was used to help subjects activate muscles over a range of excitation levels. Following pre-activation, the subject's leg was passively extended so the knee or hip joint rotated at one of three different speeds (30, 60, and 120 degrees /s). In general, it was found that the magnitude of stroke survivors' reflex response was greater compared to controls' in certain biarticular muscles, notably the gastrocnemius and medial hamstring, and the uniarticular adductor longus, and that the long-latency reflex component (between 40 and 150 ms post-movement) accounted for most of the observed differences. Furthermore, while reflex response amplitudes increased in both groups with increasing movement speed, the rate of increase was significantly larger in stroke subjects than in controls. Clinically, these findings may help explain why stroke survivors walk slowly since it is under these conditions that reflex responses better emulate those of their able-bodied counterparts.

  7. Effect of stochastic modulation of inter-pulse interval during stimulated isokinetic leg extension

    OpenAIRE

    Efe Anil Aksöz; Marco Laubacher; Stuart Binder-Macleod; Hunt, Kenneth J

    2016-01-01

    Recumbent cycling exercise achieved by functional electrical stimulation (FES) of the paralyzed leg muscles is effective for cardiopulmonary and musculoskeletal conditioning after spinal cord injury, but its full potential has not yet been realized. Mechanical power output and efficiency is very low and endurance is limited due to early onset of muscle fatigue. The aim of this work was to compare stochastic modulation of the inter-pulse interval (IPI) to constant-frequency stimulation during ...

  8. Characteristics of fast voluntary and electrically evoked isometric knee extensions during 56 days of bed rest with and without exercise countermeasure.

    NARCIS (Netherlands)

    Mulder, E.R.; Gerrits, K.H.; Rittweger, J.; Felsenberg, D.; Stegeman, D.F.; Haan, A. de

    2008-01-01

    The contractile characteristics of fast voluntary and electrically evoked unilateral isometric knee extensions were followed in 16 healthy men during 56 days of horizontal bed rest and assessed at bed rest days 4, 7, 10, 17, 24, 38 and 56. Subjects were randomized to either an inactive control group

  9. Association between regional quadriceps oxygenation and blood oxygen saturation during normoxic one-legged dynamic knee extension

    DEFF Research Database (Denmark)

    Esaki, Kazuki; Hamaoka, Takafumi; Rådegran, Göran;

    2005-01-01

    one-legged dynamic knee extension exercise (1L-KEE). Five healthy male subjects (age 25+/-2 year, height 177.8+/-4.8 cm, body weight 67.1 +/- 5.0 kg; mean +/- SD) performed 1L-KEE at 20, 40, and 60% of peak work rate (WR-peak) each for 4 min. S(fv)o2 was measured at rest and during the 3rd minute......It is not clear whether muscle oxygenation (O(2-NIRS)) measured by near-infrared spectroscopy (NIRS) correlates with femoral venous SO2 (S(fv)o2) during normoxic exercise. Therefore, the purpose of this study was to compare physiologically calibrated O(2-NIRS) with S(fv)o2 in subjects performing...

  10. Age-related differences in motor coordination during simultaneous leg flexion and finger extension: influence of temporal pressure.

    Science.gov (United States)

    Hussein, Tarek; Yiou, Eric; Larue, Jacques

    2013-01-01

    Although the effect of temporal pressure on spatio-temporal aspects of motor coordination and posture is well established in young adults, there is a clear lack of data on elderly subjects. This work examined the aging-related effects of temporal pressure on movement synchronization and dynamic stability. Sixteen young and eleven elderly subjects performed series of simultaneous rapid leg flexions in an erect posture paired with ipsilateral index-finger extensions, minimizing the difference between heel and finger movement onsets. This task was repeated ten times under two temporal conditions (self-initiated [SI] vs. reaction-time [RT]). Results showed that, first, temporal pressure modified movement synchronization; the finger extension preceded swing heel-off in RT, and inversely in SI. Synchronization error and associated standard deviation were significantly greater in elderly than in young adults in SI only, i.e. in the condition where proprioception is thought to be crucial for temporal coordination. Secondly, both groups developed a significantly shorter mediolateral (ML) anticipatory postural adjustment duration in RT (high temporal pressure) than in SI. In both groups, this shortening was compensated by an increase in the anticipatory peak of centre-of-gravity (CoG) acceleration towards the stance-leg so that ML dynamic stability at foot-off, quantified with the "extrapolated centre-of-mass", remained unchanged across temporal conditions. This increased CoG acceleration was associated with an increased anticipatory peak of ML centre-of-pressure shift towards the swing-leg in young adults only. This suggested that the ability to accelerate the CoG with the centre-of-pressure shift was degraded in elderly, probably due to weakness in the lower limb muscles. Dynamic stability at foot-off was also degraded in elderly, with a consequent increased risk of ML imbalance and falling. The present study provides new insights into the ability of elderly adults to deal

  11. Age-related differences in motor coordination during simultaneous leg flexion and finger extension: influence of temporal pressure.

    Directory of Open Access Journals (Sweden)

    Tarek Hussein

    Full Text Available Although the effect of temporal pressure on spatio-temporal aspects of motor coordination and posture is well established in young adults, there is a clear lack of data on elderly subjects. This work examined the aging-related effects of temporal pressure on movement synchronization and dynamic stability. Sixteen young and eleven elderly subjects performed series of simultaneous rapid leg flexions in an erect posture paired with ipsilateral index-finger extensions, minimizing the difference between heel and finger movement onsets. This task was repeated ten times under two temporal conditions (self-initiated [SI] vs. reaction-time [RT]. Results showed that, first, temporal pressure modified movement synchronization; the finger extension preceded swing heel-off in RT, and inversely in SI. Synchronization error and associated standard deviation were significantly greater in elderly than in young adults in SI only, i.e. in the condition where proprioception is thought to be crucial for temporal coordination. Secondly, both groups developed a significantly shorter mediolateral (ML anticipatory postural adjustment duration in RT (high temporal pressure than in SI. In both groups, this shortening was compensated by an increase in the anticipatory peak of centre-of-gravity (CoG acceleration towards the stance-leg so that ML dynamic stability at foot-off, quantified with the "extrapolated centre-of-mass", remained unchanged across temporal conditions. This increased CoG acceleration was associated with an increased anticipatory peak of ML centre-of-pressure shift towards the swing-leg in young adults only. This suggested that the ability to accelerate the CoG with the centre-of-pressure shift was degraded in elderly, probably due to weakness in the lower limb muscles. Dynamic stability at foot-off was also degraded in elderly, with a consequent increased risk of ML imbalance and falling. The present study provides new insights into the ability of

  12. Cardiovascular responses to voluntary and nonvoluntary static exercise in humans.

    Science.gov (United States)

    Friedman, D B; Peel, C; Mitchell, J H

    1992-11-01

    We have measured the cardiovascular responses during voluntary and nonvoluntary (electrically induced) one-leg static exercise in humans. Eight normal subjects were studied at rest and during 5 min of static leg extension at 20% of maximal voluntary contraction performed voluntarily and nonvoluntarily in random order. Heart rate (HR), mean arterial pressure (MAP), and cardiac output (CO) were determined, and peripheral vascular resistance (PVR) and stroke volume (SV) were calculated. HR increased from approximately 65 +/- 3 beats/min at rest to 80 +/- 4 and 78 +/- 6 beats/min (P voluntary and nonvoluntary contractions, respectively. CO increased from 5.1 +/- 0.7 to 6.0 +/- 0.8 and 6.2 +/- 0.8 l/min (P voluntary and nonvoluntary contractions, respectively. PVR and SV did not change significantly during voluntary or nonvoluntary contractions. Thus the cardiovascular responses were not different between voluntary and electrically induced contractions. These results suggest that the increases in CO, HR, SV, MAP, and PVR during 5 min of static contractions can be elicited without any contribution from a central neural mechanism (central command). However, central command could still have an important role during voluntary static exercise.

  13. An anterior cruciate ligament injury does not affect the neuromuscular function of the non-injured leg except for dynamic balance and voluntary quadriceps activation

    NARCIS (Netherlands)

    Zult, Tjerk; Gokeler, Alli; van Raay, Jos J. A. M.; Brouwer, Reinoud W.; Zijdewind, Inge; Hortobagyi, Tibor

    The function of the anterior cruciate ligament (ACL) patients' non-injured leg is relevant in light of the high incidence of secondary ACL injuries on the contralateral side. However, the non-injured leg's function has only been examined for a selected number of neuromuscular outcomes and often

  14. An anterior cruciate ligament injury does not affect the neuromuscular function of the non-injured leg except for dynamic balance and voluntary quadriceps activation

    NARCIS (Netherlands)

    Zult, Tjerk; Gokeler, Alli; van Raay, Jos J A M; Brouwer, Reinoud W; Zijdewind, Inge; Hortobágyi, Tibor

    2016-01-01

    PURPOSE: The function of the anterior cruciate ligament (ACL) patients' non-injured leg is relevant in light of the high incidence of secondary ACL injuries on the contralateral side. However, the non-injured leg's function has only been examined for a selected number of neuromuscular outcomes and o

  15. Acute changes in muscle activation and leg extension performance after different running exercises in elite long distance runners.

    Science.gov (United States)

    Vuorimaa, Timo; Virlander, Rami; Kurkilahti, Pasi; Vasankari, Tommi; Häkkinen, Keijo

    2006-02-01

    This study investigated acute changes in muscle activation and muscular power performance after three different running exercises in elite long-distance runners. Twenty-two nationally and internationally ranked long-distance runners performed first an incremental treadmill running test until exhaustion (MR) and then 40 min continuous (TR) and intermittent (2 min run/2 min rest) (IR) running exercises at an intensity of 80 and 100% of the velocity associated with VO(2max), respectively. Muscle activation and muscular power performance tests (counter-movement jumps, CMJ, and a set of ten maximal half squats from the static starting position with an extra load of 35% of the subjects, one repetition maximum) were performed before and immediately after the runs. The average mechanical power (P) of the half squats was calculated and the root mean square electromyogram (EMGrms) from the vastus lateralis, vastus medialis, gastrocnemius and biceps femoris muscles was recorded simultaneously during the half squat performances. The results showed an acute exercise-induced increase in P (ANOVA time effect, P = 0.000) together with a reduction in EMGrms of the knee extensor muscles (ANOVA time effect, P = 0.000). However, mechanical P expressed as a relative change within the set decreased after MR. In TR the improvement in P correlated positively with the maximal running performance of the runners (P muscles, and may lead to a different coordination strategy in leg extension exercises performed into the vertical direction. After continuous type of running the power improvement correlates positively with maximal endurance running capacity, whereas after intermittent type of running it correlates negatively.

  16. Comparison of selective electromyographic activity of the superficial lumbar multifidus between prone trunk extension and four-point kneeling arm and leg lift exercises

    OpenAIRE

    Kim, Jun-Seok; Kang, Min-Hyeok; Jang, Jun-Hyeok; Oh, Jae-Seop

    2015-01-01

    [Purpose] This study examined the selective electromyographic activity of the lumbar paraspinal muscles in healthy male and female subjects in the prone trunk extension (PTE) and four-point kneeling arm and leg lift (FPKAL) exercises to determine the most beneficial exercise for selective activation of the lumbar multifidus (LM). [Subjects and Methods] Twenty healthy male and female subjects participated in this study. Surface electromyographic data were collected from the left-side lumbar er...

  17. Trunk and hip muscle recruitment patterns during the prone leg extension following a lateral ankle sprain: A prospective case study pre and post injury

    Directory of Open Access Journals (Sweden)

    Lehman Gregory J

    2006-02-01

    Full Text Available Abstract Background and case presentation The prone leg extension (PLE is commonly used to identify dysfunction of muscle recruitment patterns. The prone leg extension is theorized to identify proximal muscle disturbances which are a result of distal injury or dysfunction (i.e. an ankle sprain. This case study compares the trunk and hip muscle (bilateral lower erector spine, ipsilateral hamstring and ipsilateral gluteus maximus timing during a PLE of a 27 year old female runner during a healthy state (pre ankle sprain and 2 and 8 weeks post ankle sprain. Results and discussion The gluteus maximus muscle onsets at 8 weeks post injury appeared to occur earlier compared with 2 weeks post injury. The Right Erector Spinae at 8 weeks post injury was also active earlier compared with the participant's non-injured state. A large degree of variability can be noted within trials on the same day for all muscle groups. Conclusion An acute ankle injury did not result in a delay in gluteus maximus muscle activation. The utility of the prone leg extension as a clinical and functional test is questionable due to the normal variability seen during the test and our current inability to determine what is normal and what is dysfunctional.

  18. Characterizing rapid-onset vasodilation to single muscle contractions in the human leg.

    Science.gov (United States)

    Credeur, Daniel P; Holwerda, Seth W; Restaino, Robert M; King, Phillip M; Crutcher, Kiera L; Laughlin, M Harold; Padilla, Jaume; Fadel, Paul J

    2015-02-15

    Rapid-onset vasodilation (ROV) following single muscle contractions has been examined in the forearm of humans, but has not yet been characterized in the leg. Given known vascular differences between the arm and leg, we sought to characterize ROV following single muscle contractions in the leg. Sixteen healthy men performed random ordered single contractions at 5, 10, 20, 40, and 60% of their maximum voluntary contraction (MVC) using isometric knee extension made with the leg above and below heart level, and these were compared with single isometric contractions of the forearm (handgrip). Single thigh cuff compressions (300 mmHg) were utilized to estimate the mechanical contribution to leg ROV. Continuous blood flow was determined by duplex-Doppler ultrasound and blood pressure via finger photoplethysmography (Finometer). Single isometric knee extensor contractions produced intensity-dependent increases in peak leg vascular conductance that were significantly greater than the forearm in both the above- and below-heart level positions (e.g., above heart level: leg 20% MVC, +138 ± 28% vs. arm 20% MVC, +89 ± 17%; P contractions in the leg. Collectively, these data demonstrate the presence of a rapid and robust vasodilation to single muscle contractions in the leg that is largely independent of mechanical factors, thus establishing the leg as a viable model to study ROV in humans.

  19. The bilateral leg strength deficit is present in old, young and adolescent females during isokinetic knee extension and flexion.

    Science.gov (United States)

    Kuruganti, Usha; Seaman, Kenneth

    2006-06-01

    The bilateral limb deficit (BLD) describes the difference in maximal or near maximal force generating capacity of muscles when they are contracted alone or in combination with the contralateral muscles. A deficit occurs when the summed unilateral force is greater than the bilateral force. This study examined the presence of the BLD during isokinetic knee extensions and flexions in a group of adolescent females (n=8, mean of 15+/-1 years) and compared with previously reported data by this researcher of adult and older females. Data were collected from subjects during slow (45 deg/s) isokinetic knee extensions and flexions and it was found that a BLD exists during both extension and flexion regardless of age. Furthermore, this study is the first to examine the presence of the deficit in an adolescent population. Myoelectric signal (MES) data showed that there is no difference between bilateral and unilateral isokinetic knee extensions and flexions regardless of age group.

  20. Interaction against different environmental dynamics during a leg extension task is controlled by temporal rather than amplitude scaling of muscular activity.

    Science.gov (United States)

    Wuebbenhorst, Kati; Zschorlich, Volker

    2013-10-01

    Force exertion against different mechanical environments can affect motor control strategies in order to account for the altered environmental dynamics and to maintain the ability to produce force. Here, we investigated the change of muscular activity of selected muscles of the lower extremities while the participants interacted with an external mechanical device of variable stability. Twenty-five healthy participants exerted force against the device by performing a unilateral ballistic leg extension task under 1 or 3 degrees of freedom (DoF). Directional force data and electromyographic responses from four leg muscles (TA, VM, GM, PL) were recorded. Muscle responses to the altered experimental conditions were analyzed by calculating time to peak electrical activity (TTP), peak electrical activity (PEA), slope of EMG-signal and muscle activity. It was found that neuromuscular system adjustments to the task are expressed mainly by temporal (TTP) rather than amplitude (PEA) scaling of muscular activity. This change was specific for the investigated muscles. Moreover, a selective increase of muscle activity occurred while increasing external DoF. This scheme was accompanied by a significant reduction of applicable force against the device in the unstable 3 DoF condition. The findings suggest that orchestration of movement control is linked to environmental dynamics also affecting the ability to produce force under dynamic conditions. The adjustments of the neuromuscular system are rather temporal in nature being consistent with the impulse timing hypothesis of motor control.

  1. Comparison of selective electromyographic activity of the superficial lumbar multifidus between prone trunk extension and four-point kneeling arm and leg lift exercises.

    Science.gov (United States)

    Kim, Jun-Seok; Kang, Min-Hyeok; Jang, Jun-Hyeok; Oh, Jae-Seop

    2015-04-01

    [Purpose] This study examined the selective electromyographic activity of the lumbar paraspinal muscles in healthy male and female subjects in the prone trunk extension (PTE) and four-point kneeling arm and leg lift (FPKAL) exercises to determine the most beneficial exercise for selective activation of the lumbar multifidus (LM). [Subjects and Methods] Twenty healthy male and female subjects participated in this study. Surface electromyographic data were collected from the left-side lumbar erector spinae (LES) and LM muscles during PTE and FPKAL exercises. [Results] The LM/LES ratio related to selective activation of the lumbar paraspinal muscles during the FPKAL exercise was higher than that during PTE. [Conclusion] FPKAL exercise is safe and effective for the selective activation of the LM muscle.

  2. Operant Variability and Voluntary Action

    Science.gov (United States)

    Neuringer, Allen; Jensen, Greg

    2010-01-01

    A behavior-based theory identified 2 characteristics of voluntary acts. The first, extensively explored in operant-conditioning experiments, is that voluntary responses produce the reinforcers that control them. This bidirectional relationship--in which reinforcer depends on response and response on reinforcer--demonstrates the functional nature…

  3. Biomechanics of Counterweighted One-Legged Cycling.

    Science.gov (United States)

    Elmer, Steven J; McDaniel, John; Martin, James C

    2016-02-01

    One-legged cycling has served as a valuable research tool and as a training and rehabilitation modality. Biomechanics of one-legged cycling are unnatural because the individual must actively lift the leg during flexion, which can be difficult to coordinate and cause premature fatigue. We compared ankle, knee, and hip biomechanics between two-legged, one-legged, and counterweighted (11.64 kg) one-legged cycling. Ten cyclists performed two-legged (240 W), one-legged (120 W), and counterweighted one-legged (120 W) cycling (80 rpm). Pedal forces and limb kinematics were recorded to determine work during extension and flexion. During counterweighted one-legged cycling relative ankle dorsiflexion, knee flexion, and hip flexion work were less than one-legged but greater than two-legged cycling (all P cycling were greater than one-legged but less than two-legged cycling (all P cycling reduced but did not eliminate differences in joint flexion and extension actions between one- and two-legged cycling. Even with these differences, counterweighted one-legged cycling seemed to have advantages over one-legged cycling. These results, along with previous work highlighting physiological characteristics and training adaptations to counterweighted one-legged cycling, demonstrate that this exercise is a viable alternative to one-legged cycling.

  4. The contribution of leg press and knee extension strength and power to physical function in people with knee osteoarthritis: A cross-sectional study.

    Science.gov (United States)

    Tevald, Michael A; Murray, Amanda M; Luc, Brittney; Lai, Kafai; Sohn, David; Pietrosimone, Brian

    2016-12-01

    The purposes of this study were to 1) determine the additional contributions of leg press and knee extensor power, over and above that of strength, to the performance of physical function tasks in people with knee osteoarthritis, and 2) compare the ability of bilateral leg press to unilateral knee extensor strength and power to predict functional task performance.

  5. Leg pain

    Science.gov (United States)

    ... when you walk or exercise and improves with rest. The leg is black and blue. The leg is cold ... chap 81. Marcussen B, Hogrefe C, Amendola A. Leg pain and exertional compartment syndromes. In: Miller MD, Thompson SR, eds. DeLee & Drez's ...

  6. Voluntary Slavery

    Directory of Open Access Journals (Sweden)

    Danny Frederick

    2014-06-01

    Full Text Available The permissibility of actions depends upon facts about the flourishing and separateness of persons. Persons differ from other creatures in having the task of discovering for themselves, by conjecture and refutation, what sort of life will fulfil them. Compulsory slavery impermissibly prevents some persons from pursuing this task. However, many people may conjecture that they are natural slaves. Some of these conjectures may turn out to be correct. In consequence, voluntary slavery, in which one person welcomes the duty to fulfil all the commands of another, is permissible. Life-long voluntary slavery contracts are impermissible because of human fallibility; but fixed-term slavery contracts should be legally enforceable. Each person has the temporarily alienable moral right to direct her own life.

  7. Voluntary Slavery

    Directory of Open Access Journals (Sweden)

    Danny Frederick

    2014-06-01

    Full Text Available The permissibility of actions depends upon facts about the flourishing and separateness of persons. Persons differ from other creatures in having the task of discovering for themselves, by conjecture and refutation, what sort of life will fulfil them. Compulsory slavery impermissibly prevents some persons from pursuing this task. However, many people may conjecture that they are natural slaves. Some of these conjectures may turn out to be correct. In consequence, voluntary slavery, in which one person welcomes the duty to fulfil all the commands of another, is permissible. Life-long voluntary slavery contracts are impermissible because of human fallibility; but fixed-term slavery contracts should be legally enforceable. Each person has the temporarily alienable moral right to direct her own life.

  8. Leg extension power is a pre-disaster modifiable risk factor for post-traumatic stress disorder among survivors of the Great East Japan Earthquake: a retrospective cohort study.

    Science.gov (United States)

    Momma, Haruki; Niu, Kaijun; Kobayashi, Yoritoshi; Huang, Cong; Otomo, Atsushi; Chujo, Masahiko; Tadaura, Hiroko; Nagatomi, Ryoichi

    2014-01-01

    Post-traumatic stress disorder (PTSD) is a common psychological problem following natural disasters. Although pre-disaster risk factors are important for early detection and proactive support, the examination of such has been limited to sociodemographic factors, which were largely unaffected by the disasters. We examined the association between pre-disaster physical functioning and lifestyle and PTSD symptoms five months after the earthquake in the Great East Japan Earthquake survivors who were participating in a pre-existing cohort study. We designed a retrospective cohort study of a cooperative association in Sendai from August 2010 to August 2011. In 2010, lifestyle, physical condition, and sociodemographic factors were examined by self-reported questionnaires completed by 522 employees of this organization. We also measured the leg extension power of all the participants. PTSD symptoms were evaluated by the Japanese version of the Impact of Event Scale-Revised (IES-R-J) following the earthquake of 2011. In multivariate linear regression analysis, leg extension power (β = -0.128, P = 0.025), daily drinking (β  = 0.203, P = 0.006), and depressive symptoms (β  = 0.139, P = 0.008) were associated with total score of the IES-R-J among men. Moreover, for the IES-R-J subscale, leg extension power was also negatively associated with Intrusion (β = -0.114, P = 0.045) and Hyperarousal (β = -0.163, P = 0.004) after adjusting for all other significant variables. For women, hypertension (β  = 0.226, P = 0.032) and depressive symptoms (β  = 0.205, P = 0.046) were associated with the total score of the IES-R-J. Leg extension power is a potentially modifiable pre-disaster risk factor among men for attenuating the severity of PTSD symptoms associated with great disasters such as the Great East Japan Earthquake among men.

  9. Leg extension power is a pre-disaster modifiable risk factor for post-traumatic stress disorder among survivors of the Great East Japan Earthquake: a retrospective cohort study.

    Directory of Open Access Journals (Sweden)

    Haruki Momma

    Full Text Available BACKGROUND: Post-traumatic stress disorder (PTSD is a common psychological problem following natural disasters. Although pre-disaster risk factors are important for early detection and proactive support, the examination of such has been limited to sociodemographic factors, which were largely unaffected by the disasters. We examined the association between pre-disaster physical functioning and lifestyle and PTSD symptoms five months after the earthquake in the Great East Japan Earthquake survivors who were participating in a pre-existing cohort study. METHODS: We designed a retrospective cohort study of a cooperative association in Sendai from August 2010 to August 2011. In 2010, lifestyle, physical condition, and sociodemographic factors were examined by self-reported questionnaires completed by 522 employees of this organization. We also measured the leg extension power of all the participants. PTSD symptoms were evaluated by the Japanese version of the Impact of Event Scale-Revised (IES-R-J following the earthquake of 2011. RESULTS: In multivariate linear regression analysis, leg extension power (β = -0.128, P = 0.025, daily drinking (β  = 0.203, P = 0.006, and depressive symptoms (β  = 0.139, P = 0.008 were associated with total score of the IES-R-J among men. Moreover, for the IES-R-J subscale, leg extension power was also negatively associated with Intrusion (β = -0.114, P = 0.045 and Hyperarousal (β = -0.163, P = 0.004 after adjusting for all other significant variables. For women, hypertension (β  = 0.226, P = 0.032 and depressive symptoms (β  = 0.205, P = 0.046 were associated with the total score of the IES-R-J. CONCLUSIONS: Leg extension power is a potentially modifiable pre-disaster risk factor among men for attenuating the severity of PTSD symptoms associated with great disasters such as the Great East Japan Earthquake among men.

  10. Effects of transcranial magnetic stimulation during voluntary and non-voluntary stepping movements in humans.

    Science.gov (United States)

    Solopova, I A; Selionov, V A; Kazennikov, O V; Ivanenko, Y P

    2014-09-05

    Here, we compared motor evoked potentials (MEP) in response to transcranial magnetic stimulation of the motor cortex and the H-reflex during voluntary and vibration-induced air-stepping movements in humans. Both the MEPs (in mm biceps femoris, rectus femoris and tibialis anterior) and H-reflex (in m soleus) were significantly smaller during vibration-induced cyclic leg movements at matched amplitudes of angular motion and muscle activity. These findings highlight differences between voluntary and non-voluntary activation of the spinal pattern generator circuitry in humans, presumably due to an extra facilitatory effect of voluntary control/triggering of stepping on spinal motoneurons and interneurons. The results support the idea of active engagement of supraspinal motor areas in developing central pattern generator-modulating therapies. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Voluntary Environmental Governance Arrangements

    NARCIS (Netherlands)

    van der Heijden, J.

    2012-01-01

    Voluntary environmental governance arrangements have focal attention in studies on environmental policy, regulation and governance. The four major debates in the contemporary literature on voluntary environmental governance arrangements are studied. The literature falls short of sufficiently

  12. Voluntary Environmental Governance Arrangements

    NARCIS (Netherlands)

    van der Heijden, J.

    2012-01-01

    Voluntary environmental governance arrangements have focal attention in studies on environmental policy, regulation and governance. The four major debates in the contemporary literature on voluntary environmental governance arrangements are studied. The literature falls short of sufficiently specify

  13. Voluntary Service System (VSS)

    Data.gov (United States)

    Department of Veterans Affairs — Voluntary Service System (VSS) is a national-level application which replaced the site-based Voluntary Timekeeping System (VTK). VTK was used for many years at the...

  14. Muscle fatigue and exhaustion during dynamic leg exercise in normoxia and hypobaric hypoxia

    DEFF Research Database (Denmark)

    Fulco, C S; Lewis, S F; Frykman, Peter

    1996-01-01

    Using an exercise device that integrates maximal voluntary static contraction (MVC) of knee extensor muscles with dynamic knee extension, we compared progressive muscle fatigue, i.e., rate of decline in force-generating capacity, in normoxia (758 Torr) and hypobaric hypoxia (464 Torr). Eight...... healthy men performed exhaustive constant work rate knee extension (21 +/- 3 W, 79 +/- 2 and 87 +/- 2% of 1-leg knee extension O2 peak uptake for normoxia and hypobaria, respectively) from knee angles of 90-150 degrees at a rate of 1 Hz. MVC (90 degrees knee angle) was performed before dynamic exercise...... and during MVC force was 578 +/- 29 N in normoxia and 569 +/- 29 N in hypobaria before exercise and fell, at exhaustion, to similar levels (265 +/- 10 and 284 +/- 20 N for normoxia and hypobaria, respectively; P > 0.05) that were higher (P

  15. [The influence of the leg load and the support mobility under leg on the anticipatory postural adjustment].

    Science.gov (United States)

    Kazennikov, O V; Kireeva, T B; Shlykov, V Iu

    2015-01-01

    Anticipatory postural adjustment is an essential part of equilibrium maintainance during standing in human. So changes in stance condition could affect both control of equilibrium and anticipatory adjustment. Anticipatory changes in the stabilogram of each leg were studied in standing subject during the early stage of quick right arm lifting while legs were on two separated supports. The center of pressure (CP) movement was analyzed in three variants of experiment: both legs on immovable support, with only right leg on the movable support and with only left leg on the moveable support. In each standing condition subject stood with symmetrical load on two legs or with the load voluntary transferred to one leg. The anticipatory CP shift depended on the mobility of the support under the leg and on loading of the leg. While standing on unmovable supports with symmetrical load on the legs before lifting of the right arm CP of right leg shifted backward and CP of left leg--forward. While standing with one leg on movable support the anticipatory CP shift of this leg was small and did not depend on the load on the leg. However the shift of CP of the leg that was placed on the unmovable support depended on the load in the same way as in the case when both legs were on unmovable supports. Results suggested that since on movable support the support and proprioceptive afferent flow from distal part of the leg that was did not supply unambiguous information about body position, the role of distal joints in posture control is reduced.

  16. Selective contribution of each hamstring muscle to anterior cruciate ligament protection and tibiofemoral joint stability in leg-extension exercise: a simulation study.

    Science.gov (United States)

    Biscarini, Andrea; Botti, Fabio Massimo; Pettorossi, Vito Enrico

    2013-09-01

    A biomechanical model was developed to simulate the selective effect of the co-contraction force provided by each hamstring muscle on the shear and compressive tibiofemoral joint reaction forces, during open kinetic-chain knee-extension exercises. This model accounts for instantaneous values of knee flexion angle [Formula: see text], angular velocity and acceleration, and for changes in magnitude, orientation, and application point of external resistance. The tibiofemoral shear force (TFSF) largely determines the tensile force on anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). Biceps femoris is the most effective hamstring muscle in decreasing the ACL-loading TFSF developed by quadriceps contractions for [Formula: see text]. In this range, the semimembranosus generates the dominant tibiofemoral compressive force, which enhances joint stability, opposes anterior/posterior tibial translations, and protects cruciate ligaments. The semitendinosus force provides the greatest decreasing gradient of ACL-loading TFSF for [Formula: see text], and the greatest increasing gradient of tibiofemoral compressive force for [Formula: see text]. However, semitendinosus efficacy is strongly limited by its small physiological section. Hamstring muscles behave as a unique muscle in enhancing the PCL-loading TFSF produced by quadriceps contractions for [Formula: see text]. The levels of hamstrings co-activation that suppress the ACL-loading TFSF considerably shift when the knee angular acceleration is changed while maintaining the same level of knee extensor torque by a concurrent adjustment in the magnitude of external resistance. The knowledge of the specific role and the optimal activation level of each hamstring muscle in ACL protection and tibiofemoral stability are fundamental for planning safe and effective rehabilitative knee-extension exercises.

  17. Isokinetic leg strength and power in elite handball players.

    Science.gov (United States)

    González-Ravé, José M; Juárez, Daniel; Rubio-Arias, Jacobo A; Clemente-Suarez, Vicente J; Martinez-Valencia, María A; Abian-Vicen, Javier

    2014-06-28

    Isokinetic strength evaluation of the knee flexion and extension in concentric mode of contraction is an important part of the comprehensive evaluation of athletes. The aims of this study were to evaluate the isokinetic knee peak torque in both the extension and flexion movement in the dominant and non-dominant leg, and the relationship with jumping performance. Twelve elite male handball players from the top Spanish handball division voluntary participated in the study (age 27.68 ± 4.12 years; body mass 92.89 ± 12.34 kg; body height 1.90 ± 0.05 m). The knee extensor and flexor muscle peak torque of each leg were concentrically measured at 60º/s and 180º/s with an isokinetic dynamometer. The Squat Jump and Countermovement Jump were performed on a force platform to determine power and vertical jump height. Non-significant differences were observed between legs in the isokinetic knee extension (dominant= 2.91 ± 0.53 Nm/kg vs non-dominant = 2.70 ± 0.47 Nm/kg at 60º/s; dominant = 1.90 ± 0.31 Nm/kg vs non-dominant = 1.83 ± 0.29 Nm/kg at 180º/s) and flexion peak torques (dominant = 1.76 ± 0.29 Nm/kg vs non-dominant = 1.72 ± 0.39 Nm/kg at 60º/s; dominant = 1.30 ± 0.23 Nm/kg vs non-dominant = 1.27 ± 0.35 Nm/kg at 180º/s). Low and non-significant correlation coefficients were found between the isokinetic peak torques and vertical jumping performance (SJ = 31.21 ± 4.32 cm; CMJ = 35.89 ± 4.20 cm). Similar isokinetic strength was observed between the legs; therefore, no relationship was found between the isokinetic knee flexion and extension peak torques as well as vertical jumping performance in elite handball players.

  18. Effect of acute hypoxia on muscle blood flow, VO₂p, and [HHb] kinetics during leg extension exercise in older men.

    Science.gov (United States)

    Zerbini, Livio; Spencer, Matthew D; Grey, Tyler M; Murias, Juan M; Kowalchuk, John M; Schena, Federico; Paterson, Donald H

    2013-07-01

    The adjustment of pulmonary oxygen uptake (VO2p), heart rate (HR), limb blood flow (LBF), and muscle deoxygenation [HHb] was examined during the transition to moderate-intensity, knee-extension exercise in six older adults (70 ± 4 years) under two conditions: normoxia (FIO₂ = 20.9 %) and hypoxia (FIO₂ = 15 %). The subjects performed repeated step transitions from an active baseline (3 W) to an absolute work rate (21 W) in both conditions. Phase 2 VO₂p, HR, LBF, and [HHb] data were fit with an exponential model. Under hypoxic conditions, no change was observed in HR kinetics, on the other hand, LBF kinetics was faster (normoxia 34 ± 3 s; hypoxia 28 ± 2), whereas the overall [HHb] adjustment (τ' = TD + τ) was slower (normoxia 28 ± 2; hypoxia 33 ± 4 s). Phase 2 VO₂p kinetics were unchanged (p < 0.05). The faster LBF kinetics and slower [HHb] kinetics reflect an improved matching between O₂ delivery and O₂ utilization at the microvascular level, preventing the phase 2 VO₂p kinetics from become slower in hypoxia. Moreover, the absolute blood flow values were higher in hypoxia (1.17 ± 0.2 L min(-1)) compared to normoxia (0.96 ± 0.2 L min(-1)) during the steady-state exercise at 21 W. These findings support the idea that, for older adults exercising at a low work rate, an increase of limb blood flow offsets the drop in arterial oxygen content (CaO₂) caused by breathing an hypoxic mixture.

  19. Sympathetic adaptations to one-legged training

    Science.gov (United States)

    Ray, C. A.

    1999-01-01

    The purpose of the present study was to determine the effect of leg exercise training on sympathetic nerve responses at rest and during dynamic exercise. Six men were trained by using high-intensity interval and prolonged continuous one-legged cycling 4 day/wk, 40 min/day, for 6 wk. Heart rate, mean arterial pressure (MAP), and muscle sympathetic nerve activity (MSNA; peroneal nerve) were measured during 3 min of upright dynamic one-legged knee extensions at 40 W before and after training. After training, peak oxygen uptake in the trained leg increased 19 +/- 2% (P leg exercise and indicates that attenuation of MSNA to exercise reported with forearm training also occurs with leg training.

  20. The spinal reflex cannot be perceptually separated from voluntary movements.

    Science.gov (United States)

    Ghosh, Arko; Haggard, Patrick

    2014-01-01

    Both voluntary and involuntary movements activate sensors in the muscles, skin, tendon and joints. As limb movement can result from a mixture of spinal reflexes and voluntary motor commands, the cortical centres underlying conscious proprioception might either aggregate or separate the sensory inputs generated by voluntary movements from those generated by involuntary movements such as spinal reflexes. We addressed whether healthy volunteers could perceive the contribution of a spinal reflex during movements that combined both reflexive and voluntary contributions. Volunteers reported the reflexive contribution in leg movements that were partly driven by the knee-jerk reflex induced by a patellar tendon tap and partly by voluntary motor control. In one condition, participants were instructed to kick back in response to a tendon tap. The results were compared to reflexes in a resting baseline condition without voluntary movement. In a further condition, participants were instructed to kick forwards after a tap. Volunteers reported the perceived reflex contribution by repositioning the leg to the perceived maximum displacement to which the reflex moved the leg after each tendon tap. In the resting baseline condition, the reflex was accurately perceived. We found a near-unity slope of linear regressions of perceived on actual reflexive displacement. Both the slope value and the quality of regression fit in individual volunteers were significantly reduced when volunteers were instructed to generate voluntary backward kicks as soon as they detected the tap. In the kick forward condition, kinematic analysis showed continuity of reflex and voluntary movements, but the reflex contribution could be estimated from electromyography (EMG) recording on each trial. Again, participants' judgements of reflexes showed a poor relation to reflex EMG, in contrast to the baseline condition. In sum, we show that reflexes can be accurately perceived from afferent information. However

  1. Déficit bilateral nos movimentos de flexão e extensão de perna e flexão do cotovelo Déficit bilateral en los movimientos de flexion y extension de la pierna y flexion del codo Bilateral deficit in leg flexion and extension and elbow flexion movements

    Directory of Open Access Journals (Sweden)

    Christianne Pereira Giesbrecht Chaves

    2004-12-01

    áxima (CM en la flexión y extensión de pierna e flexión del de codo aisladamente y entre la suma de esos dos resultados con aquel desarrollado simultaneamente por las dos piernas y los dos brazos, respectivamente. Sometemos a 60 indivíduos al ejercicio de flexión y extensión de pierna y a flexión de codo a un test de 1RM. Los resultados para los movimientos de flexión y extensión de pierna y flexión de codo izquierdos y derechos en la CM fueron de 31,6 (± 7,9, 32,0 (± 8,0, 20,2 (± 9,2, 20,2 (± 9,8, 29,3 (± 13,9 e 29,8 (± 14,1 kg respectivamente, y se mostraron similares (p > 0,05 y fuertemente asociados (r = 0,96, 0,96 e 0,98. Comparando la suma de los valores unilaterales con los de ejecución bilateral, la CM presentó una diferencia significativa para los movimientos de extensión de pierna (p = 0,04 y flexión de codo (p = 0,03, el mismo no fué observado en el movimiento de flexión de pierna (p = 0,75. Este resultado puede ser explicado por el menor incremento de carga - dos kilos y medio en este último movimiento en relación a los dos movimientos anteriores - cinco kilos. A pesar de la mayoría de los sujetos sean diestros, no hubo diferencias unilaterales en la CM a pesar de no todos estar entrenados. La suma de los resultados unilaterales fué mayor en 9,8% y 4,0% para los movimientos de extensión de la pierna y flexión del codo, respectivamente, de aquel obtenido bilateralmente, mostrando, probablemente una limitación central en la coordenación motora de un movimiento complejo hecho en máxima velocidad y con carga elevada. Por otro lado, en el movimiento de flexión de pierna, la suma de los resultados unilaterales fué inferior a la bilateral (-0,6%, presentando un posible aprendizage del movimiento y adaptación al entrenamiento con pesos a partir de las doce semanas.Endurance exercises (EE may be performed unilaterally and bilaterally. The objective was to compare the maximum load (ML in leg flexion and extension and elbow flexion alone

  2. Strength Training to Contraction Failure Increases Voluntary Activation of the Quadriceps Muscle Shortly After Total Knee Arthroplasty

    DEFF Research Database (Denmark)

    Mikkelsen, Elin Karin; Jakobsen, Thomas Linding; Holsgaard-Larsen, Anders;

    2016-01-01

    OBJECTIVE: The objective of this study was to investigate voluntary activation of the quadriceps muscle during one set of knee extensions performed until contraction failure in patients shortly after total knee arthroplasty. DESIGN: This was a cross-sectional study of 24 patients with total knee...... arthroplasty. One set of knee extensions was performed until contraction failure, using a predetermined 10 repetition maximum loading. In the operated leg, electromyographic (EMG) activity of the lateral and medial vastus, semitendinosus, and biceps femoris muscles was recorded during the set. Muscle activity...... (%EMGmax) and median power frequency of the EMG power spectrum were calculated for each repetition decile (10%-100% contraction failure). RESULTS: Muscle activity increased significantly over contractions from a mean of 90.0 and 93.6 %EMGmax (lateral vastus and medial vastus, respectively) at 10...

  3. Reconstruction of foot flexion-extension function after replantation of amputated leg%小腿中段离断再植后重建足跖屈背伸功能

    Institute of Scientific and Technical Information of China (English)

    陈秋生; 余斌; 杨建成; 江浩; 陈霞; 竺筠雯

    2001-01-01

    Objective To investigate the foot function reconstruction after replantation of amputated leg. Methods The n erveless injury muscle in the amputated limbs was cut off, a section tensor fascia lata was resected off to replace the injured muscle. Meanwhile, transfer biceps femoris muscle and sartoriu s muscle to strengthen extensive muscles, and transfer semimembranosus muscle an d gracilis muscle to strengthen flexion muscles. Postoperation functional exer cises of the ankle was carried out. Results 2 patients were tre ated with this t echnique, followed up for more than 2 years. The extension and flexion muscle st rength reached MRC4 with satisfactory ankle function, the range of motion of ank le was restored nearly to normal. Conclusion The technique is e ffective to reconstruct most functions of the normal muscles and restore foot function.%目的 探讨小腿中段离断再植后足跖屈背伸功能重建的方法 。方法 常规断肢再植,术中将离断肢远段失神经支配的肌组织切除,只 保留肌腱及肌腱膜,切取髂胫束条桥接远端背伸肌腱和近端肌腹,同时和前移缝匠肌、股二 头肌长头缝接,加强足背伸肌力;桥接远端跖屈肌腱和近端肌腹,同时和游离的半腱肌、股 薄肌缝接,加强足跖屈肌力。结果 治疗2例,分别随访2年8个月及2年5个 月,足背伸、跖屈肌力达Ⅳ~Ⅳ+,踝关节活动度近正常。结论 应用髂 胫束条桥接远断端的肌腱和近断端的正常肌组织,同时利用缝匠肌、股二头肌、半腱肌、股 薄肌加强足的背伸、跖屈肌力,是一种有效的功能重建方法。

  4. Restless Legs Syndrome Foundation

    Science.gov (United States)

    ... Into Relieved Are you experiencing symptoms linked to restless legs syndrome (RLS)? Find tools and support to help get ... I couldn’t sleep. Fortunately, I found the Restless Legs Syndrome Foundation and learned what type of doctor to ...

  5. Restless Legs Syndrome

    Science.gov (United States)

    ... and Teens, Men, WomenTags: neurological disorders, restless legs syndrome, RLS, sitting, sleep disorders, sleeping, uncomfortable feeling in legs at rest Family Health, Kids and Teens, Men, Women November ...

  6. Voluntary attention increases perceived spatial frequency.

    Science.gov (United States)

    Abrams, Jared; Barbot, Antoine; Carrasco, Marisa

    2010-08-01

    Voluntary covert attention selects relevant sensory information for prioritized processing. The behavioral and neural consequences of such selection have been extensively documented, but its phenomenology has received little empirical investigation. Involuntary attention increases perceived spatial frequency (Gobell & Carrasco, 2005), but involuntary attention can differ from voluntary attention in its effects on performance in tasks mediated by spatial resolution (Yeshurun, Montagna, & Carrasco, 2008). Therefore, we ask whether voluntary attention affects the subjective appearance of spatial frequency--a fundamental dimension of visual perception underlying spatial resolution. We used a demanding rapid serial visual presentation task to direct voluntary attention and measured perceived spatial frequency at the attended and unattended locations. Attention increased the perceived spatial frequency of suprathreshold stimuli and also improved performance on a concurrent orientation discrimination task. In the control experiment, we ruled out response bias as an alternative account by using a lengthened interstimulus interval, which allows observers to disengage attention from the cued location. In contrast to the main experiment, the observers showed neither increased perceived spatial frequency nor improved orientation discrimination at the attended location. Thus, this study establishes that voluntary attention increases perceived spatial frequency. This phenomenological consequence links behavioral and neurophysiological studies on the effects of attention.

  7. Restless legs syndrome

    Directory of Open Access Journals (Sweden)

    Ovallath S

    2012-10-01

    Full Text Available Sujith Ovallath, P DeepaJames Parkinson's Movement Disorder Research Centre, Kannur Medical College, Kerala, IndiaBackground: Restless legs syndrome (RLS is a common sleep-related disorder characterized by abnormal sensation and an urge to move the lower limbs. Symptoms occur at rest in the evening or at night, and they are alleviated by moving the affected extremity or by walking. Although the exact etiopathogenesis of RLS remains elusive, the rapid improvement of symptoms with dopaminergic agents suggests that dopaminergic system dysfunction may be a basic mechanism. Dopaminergic agents are the best-studied agents, and are considered first-line treatment of RLS.Objective: To review the diagnostic criteria, clinical features, etiopathogenesis, and the treatment options of RLS.Methods: The suggestions are based on evidence from studies published in peer-reviewed journals, or upon a comprehensive review of the medical literature.Results/conclusion: Extensive data are available for proving the link between the dopaminergic system and RLS. A possible genetic link also has been studied extensively. Dopamine agonists, especially pramipexole and ropinirole, are particularly useful in the treatment of RLS. Pharmacological treatment should however be limited to those patients who suffer from clinically relevant RLS with impaired sleep quality or quality of life.Keywords: dopamine, levodopa, pramipexole

  8. Rethinking voluntary euthanasia.

    Science.gov (United States)

    Stoyles, Byron J; Costreie, Sorin

    2013-12-01

    Our goal in this article is to explicate the way, and the extent to which, euthanasia can be voluntary from both the perspective of the patient and the perspective of the health care providers involved in the patient's care. More significantly, we aim to challenge the way in which those engaged in ongoing philosophical debates regarding the morality of euthanasia draw distinctions between voluntary, involuntary, and nonvoluntary euthanasia on the grounds that drawing the distinctions in the traditional manner (1) fails to reflect what is important from the patient's perspective and (2) fails to reflect the significance of health care providers' interests, including their autonomy and integrity.

  9. Pavlov's conceptualization of voluntary movements within the framework of the theory of higher nervous activity.

    Science.gov (United States)

    Windholz, G

    1998-01-01

    Pavlov became interested in the nature of voluntary movements after receiving Konorski and Miller's letter in 1928 describing their experiments on conditioning of motor movements in dogs. Their paradigmatic experiment involved presenting an indifferent stimulus, followed by passive raising of the dog's leg and then reinforcement. If the same stimulus was provided during a number of trials, the animal lifted its corresponding leg. In 1928 Pavlov asked his students to condition motor movements in his laboratory. Although their findings were equivocal, Pavlov incorporated the so-called voluntary movements into his theory of higher nervous activity. Voluntary movements were responses to external environmental contingencies. On the cortical level, the motor analyzer's cells had both afferent and efferent functions. In Pavlov's view, the motor analyzer's cells established connections with the afferent cells of other sensory analyzers. Pavlov held that motor movements, as responses to external and internal environments, give humans the illusion of voluntary behavior.

  10. Analysis of Foot Slippage Effects on an Actuated Spring-mass Model of Dynamic Legged Locomotion

    National Research Council Canada - National Science Library

    Yizhar Or; Moti Moravia

    2016-01-01

      The classical model of spring-loaded inverted pendulum (SLIP) and its extensions have been widely accepted as a simple description of dynamic legged locomotion at various scales in humans, legged robots and animals...

  11. Voluntary Public Unemployment Insurance

    DEFF Research Database (Denmark)

    O. Parsons, Donald; Tranæs, Torben; Bie Lilleør, Helene

    Denmark has drawn much attention for its active labor market policies, but is almost unique in offering a voluntary public unemployment insurance program requiring a significant premium payment. A safety net program – a less generous, means-tested social assistance plan – completes the system...

  12. Repeatability of maximal voluntary force and of surface EMG variables during voluntary isometric contraction of quadriceps muscles in healthy subjects.

    Science.gov (United States)

    Rainoldi, A; Bullock-Saxton, J E; Cavarretta, F; Hogan, N

    2001-12-01

    The repeatability of initial values and rate of change of EMG signal mean spectral frequency (MNF), average rectified values (ARV), muscle fiber conduction velocity (CV) and maximal voluntary contraction (MVC) was investigated in the vastus medialis obliquus (VMO) and vastus lateralis (VL) muscles of both legs of nine healthy male subjects during voluntary, isometric contractions sustained for 50 s at 50% MVC. The values of MVC were recorded for both legs three times on each day and for three subsequent days, while the EMG signals have been recorded twice a day for three subsequent days. The degree of repeatability was investigated using the Fisher test based upon the ANalysis Of VAriance (ANOVA), the Standard Error of the Mean (SEM) and the Intraclass Correlation Coefficient (ICC). Data collected showed a high level of repeatability of MVC measurement (normalized SEM from 1.1% to 6.4% of the mean). MNF and ARV initial values also showed a high level of repeatability (ICC>70% for all muscles and legs except right VMO). At 50% MVC level no relevant pattern of fatigue was observed for the VMO and VL muscles, suggesting that other portions of the quadriceps might have contributed to the generated effort. These observations seem to suggest that in the investigation of muscles belonging to a multi-muscular group at submaximal level, the more selective electrically elicited contractions should be preferred to voluntary contractions.

  13. Steerable Hopping Six-Legged Robot

    Science.gov (United States)

    Younse, Paulo; Aghazarian, Hrand

    2010-01-01

    The figure depicts selected aspects of a six-legged robot that moves by hopping and that can be steered in the sense that it can be launched into a hop in a controllable direction. This is a prototype of hopping robots being developed for use in scientific exploration of rough terrain on remote planets that have surface gravitation less than that of Earth. Hopping robots could also be used on Earth, albeit at diminished hopping distances associated with the greater Earth gravitation. The upper end of each leg is connected through two universal joints to an upper and a lower hexagonal frame, such that the tilt of the leg depends on the relative position of the two frames. Two non-back-driveable worm-gear motor drives are used to control the relative position of the two frames along two axes 120 apart, thereby controlling the common tilt of all six legs and thereby, further, controlling the direction of hopping. Each leg includes an upper and a lower aluminum frame segment with a joint between them. A fiberglass spring, connected via hinges to both segments, is used to store hopping energy prior to launch into a hop and to cushion the landing at the end of the hop. A cable for loading the spring is run into each leg through the center of the universal joints and then down along the center lines of the segments to the lower end of the leg. A central spool actuated by a motor with a harmonic drive and an electromagnetic clutch winds in all six cables to compress all six springs (thereby also flexing all six legs) simultaneously. To ensure that all the legs push off and land in the same direction, timing- belt pulley drives are attached to the leg segments, restricting the flexing and extension of all six legs to a common linear motion. In preparation for a hop, the spool can be driven to load the spring legs by an amount corresponding to a desired hop distance within range. The amount of compression can be computed from the reading of a shaft-angle encoder that

  14. Leg contracture in mice: an assay of normal tissue response

    Energy Technology Data Exchange (ETDEWEB)

    Stone, H.B.

    1984-07-01

    Leg contracture, defined as the difference in extensibility of the control and irradiated hind legs of mice, was found to correlate with single doses of radiation from about 20 to 80 Gy. The time of development of the early phase of the response coincided with that reported for the appearance of the acute skin response, and in some cases, partially reversed as this reaction healed. The contracture then progressed again at a moderate rate through 90 days, and then more slowly through one year. Skin contraction, measured by decrease in intertattoo distance, was assayed in the same mice. It followed the same time course as leg contracture, but had a different dose-response relationship. To determine the contribution of skin contraction to the overall leg contracture response, mice were sacrificed and the leg contracture measured before and after the removal of the skin of the leg. After doses of up to 30 Gy, little contracture remained from skinning the leg, indicating that skin contraction was largely responsible for leg contracture in this dose range. After doses of about 45 Gy and above, some contracture remained in the skinned legs, although less than in intact legs. There was little or no enhancement of either skin contraction or leg contracture by the hypoxic cell sensitizers metronidazole or misonidazole.

  15. Lyden-af-Leg

    DEFF Research Database (Denmark)

    Toft, Herdis

    Præsentation af seniorforsker-projekt Lyden-af-Leg i et traderingsperspektiv og med indledende fokus på YouTube som traderings-platform.......Præsentation af seniorforsker-projekt Lyden-af-Leg i et traderingsperspektiv og med indledende fokus på YouTube som traderings-platform....

  16. Sympathetic adaptations to one-legged training

    Science.gov (United States)

    Ray, C. A.

    1999-01-01

    The purpose of the present study was to determine the effect of leg exercise training on sympathetic nerve responses at rest and during dynamic exercise. Six men were trained by using high-intensity interval and prolonged continuous one-legged cycling 4 day/wk, 40 min/day, for 6 wk. Heart rate, mean arterial pressure (MAP), and muscle sympathetic nerve activity (MSNA; peroneal nerve) were measured during 3 min of upright dynamic one-legged knee extensions at 40 W before and after training. After training, peak oxygen uptake in the trained leg increased 19 +/- 2% (P training (108 +/- 5 to 96 +/- 5 beats/min and 132 +/- 8 to 119 +/- 4 mmHg, respectively, during the third minute of exercise; P training. However, MSNA was significantly less during the third minute of exercise after training (32 +/- 2 to 22 +/- 3 bursts/min; P training effect on MSNA remained when MSNA was expressed as bursts per 100 heartbeats. Responses to exercise in five untrained control subjects were not different at 0 and 6 wk. These results demonstrate that exercise training prolongs the decrease in MSNA during upright leg exercise and indicates that attenuation of MSNA to exercise reported with forearm training also occurs with leg training.

  17. Effects of aging on maximal and rapid velocity capacities of the leg extensors.

    Science.gov (United States)

    Thompson, Brennan J; Conchola, Eric C; Palmer, Ty B; Stock, Matt S

    2014-10-01

    Declines in muscle strength and power are commonly reported as a consequence of aging; however, few studies have investigated the influence of aging on maximal and rapid velocity characteristics. The objective of this study was to examine the effects of aging on maximal and rapid velocity characteristics of the leg extensor muscles. Twenty-three young (age=25±3yrs) and twenty-one old (72±4yrs) men performed three leg extension maximal voluntary contractions (MVCs) at 240°·s(-1) and at maximum unloaded velocity (Vmax). Vmax was calculated as the highest velocity attained during the unloaded MVC and RVD was the linear slope of the velocity-time curve for the 240deg·s(-1) (RVD240) and maximum unloaded velocity (RVD-Vmax) contractions. The old men exhibited lower (Pmuscle to generate velocity rapidly versus the ability to generate maximal velocity. Such findings highlight the importance of time-dependent velocity measures when assessing the effects of aging on rapid velocity capacities.

  18. Leg 179 summary

    Digital Repository Service at National Institute of Oceanography (India)

    Pettigrew, T.J.; Casey, J.F.; Miller, D.J.; Araki, E.; Boissonnas, R.; Busby, R.; Einaudi, F.; Gerdom, M.; Guo, Z.P.; Hopkins, H.; Myers, G.; Rao, D.G.; Shibata, T.; Thy, P.

    Ocean Drilling Program (ODP) Leg 179 set out with two primary objectives. These objectives were (1) testing the recently developed hammer drill-in casing system on the Atlantis Bank, Southwest Indian Ridge (SWIR), and (2) drilling a cased reentry...

  19. RESTLESS LEGS SYNDROME

    Directory of Open Access Journals (Sweden)

    Dmitriy Valer'evich Artem'ev

    2009-01-01

    Full Text Available The paper describes the epidemiology, etiology, pathogenesis, clinical picture, diagnosis, differential diagnosis, and treatment of restless legs syndrome. Recommendations are given how to choose therapeutic modalities and drugs in relation to different factors.

  20. Voluntary Simplicity: A Lifestyle Option.

    Science.gov (United States)

    Pestle, Ruth E.

    This guide provides practical ideas for incorporating the concept of voluntary simplicity into home economics classes. Discussed in the first chapter are the need to study voluntary simplicity, its potential contributions to home economics, and techniques and a questionnaire for measuring student attitudes toward the concept. The remaining…

  1. Toward voluntary parenthood.

    Science.gov (United States)

    Scarr, S

    2000-06-01

    David Lykken's proposal to license married parents for child rearing, and to deny the same opportunity to single and inept parents, springs from his deep concern for millions of youngsters cruelly subjected to abusive and neglectful rearing circumstances. Children from such inadequate homes grow up to have high rates of school failure, criminality, and drug addiction. The problem is clear, but Lykken's remedies of mandated marriage and parental licensure are unacceptable in U.S. society, where our reproductive rights are fortunately protected by our Constitution. As a devoted proponent of reproductive rights, I propose a legally and morally acceptable proposal to the same end. Increasing women's effective control of reproduction and moving toward entirely voluntary parenthood will accomplish the same goals without compromising our civil liberties.

  2. Venous leg ulcers.

    Science.gov (United States)

    Nelson, E Andrea

    2011-12-21

    Leg ulcers usually occur secondary to venous reflux or obstruction, but 20% of people with leg ulcers have arterial disease, with or without venous disorders. Between 1.5 and 3.0/1000 people have active leg ulcers. Prevalence increases with age to about 20/1000 in people aged over 80 years. We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of standard treatments, adjuvant treatments, and organisational interventions for venous leg ulcers? What are the effects of advice about self-help interventions in people receiving usual care for venous leg ulcers? What are the effects of interventions to prevent recurrence of venous leg ulcers? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2011 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). We found 101 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. In this systematic review we present information relating to the effectiveness and safety of the following interventions: compression bandages and stockings, cultured allogenic (single or bilayer) skin replacement, debriding agents, dressings (cellulose, collagen, film, foam, hyaluronic acid-derived, semi-occlusive alginate), hydrocolloid (occlusive) dressings in the presence of compression, intermittent pneumatic compression, intravenous prostaglandin E1, larval therapy, laser treatment (low-level), leg ulcer clinics, multilayer elastic system, multilayer elastomeric (or non-elastomeric) high-compression regimens or bandages, oral treatments (aspirin, flavonoids, pentoxifylline, rutosides, stanozolol, sulodexide

  3. [Restless legs syndrome].

    Science.gov (United States)

    Lai, Szu-Chia; Chen, Rou-Shayn

    2008-03-01

    The restless legs syndrome (RLS) is a common neurological disorder to take possession of increasing attention. RLS is characterized by an urge to move the legs, usually accompanied by uncomfortable or unpleasant sensations, that occurs or worsen at rest and is relieved by activity. The symptoms of RLS have a major impact on nocturnal sleep and daytime functions. The clinical diagnostic criteria were established and published in 2003 by International Restless Legs Syndrome Study Group (IRLSSG). All four essential criteria must be met for a positive diagnosis. However, RLS encompassed an idiopathic form of genetic or unknown origin and secondary forms associated with many causes. Special awareness should be kept for differential diagnosis such as uremia, iron deficiency anemia, polyneuropathy, rheumatoid arthritis, and other neurodegenerative diseases. Polysomnography, actinography, L-dopa loading test, and suggested immobilization test (SIT) are helpful tools to reduce the diagnostic puzzle of false positive and false negative. Pathophysiological concepts of RLS are essentially based on the neuroimaging and neurophysiological data to assume a dysfunction of the dopaminergic system, possibly on the All neuron group localized in the hypothalamus. These neurons modulate spinal excitability and alter the sensory processing predominantly of leg afferents. Treatment may be closely linked to the dopaminergic system and iron metabolism. Dopaminergic stimulation with levodopa or dopamine agonists is the first choice in idiopathic restless legs syndrome, but the long-term adverse effect of augmentation should be carefully monitored.

  4. Hemoglobinopathies and Leg Ulcers.

    Science.gov (United States)

    Alavi, Afsaneh; Kirsner, Robert S

    2015-09-01

    Major hemoglobinopathies, including sickle cell anemia, are becoming a global health issue. Leg ulcers are the most common cutaneous manifestation of sickle cell disease and an important contributor to morbidity burden in this population. Leg ulcers following sickling disorders are extremely painful, and hard to heal. The clinical evidence for the optimal management of these ulcers is limited. Treating the cause and the strategies to prevent sickling are the mainstay of treatment. The basic principles of wound bed preparation and compression therapy is beneficial in these patients.

  5. Fatigue-related firing of muscle nociceptors reduces voluntary activation of ipsilateral but not contralateral lower limb muscles.

    Science.gov (United States)

    Kennedy, David S; Fitzpatrick, Siobhan C; Gandevia, Simon C; Taylor, Janet L

    2015-02-15

    During fatiguing upper limb exercise, maintained firing of group III/IV muscle afferents can limit voluntary drive to muscles within the same limb. It is not known if this effect occurs in the lower limb. We investigated the effects of group III/IV muscle afferent firing from fatigued ipsilateral and contralateral extensor muscles and ipsilateral flexor muscles of the knee on voluntary activation of the knee extensors. In three experiments, we examined voluntary activation of the knee extensors by measuring changes in superimposed twitches evoked by femoral nerve stimulation. Subjects attended on 2 days for each experiment. On one day a sphygmomanometer cuff occluded blood flow of the fatigued muscles to maintain firing of group III/IV muscle afferents. After a 2-min extensor contraction (experiment 1; n = 9), mean voluntary activation was lower with than without maintained ischemia (47 ± 19% vs. 87 ± 8%, respectively; P contraction (MVC) (experiment 2; n = 8), mean voluntary activation was also lower with than without ischemia (59 ± 21% vs. 79 ± 9%; P muscle afferents reduces voluntary activation of the fatigued muscle and nonfatigued antagonist muscles in the same leg. However, group III/IV muscle afferents from the fatigued left leg had no effect on the unfatigued right leg. This suggests that any "crossover" of central fatigue in the lower limbs is not mediated by group III/IV muscle afferents.

  6. Analyzing voluntary medical incident reports.

    Science.gov (United States)

    Gong, Yang; Richardson, James; Zhijian, Luan; Alafaireet, Patricia; Yoo, Illhoi

    2008-11-06

    Voluntary medical incident reports lacking consistency and accuracy impede the ultimate use of the reports for patient safety research. To improve this, two coders examined harm score usage in a voluntary medical incident reporting system where the harm scores were selected from a predefined list by different reporters. The two coders inter-rater agreement percent was 82%. The major categories and reviewed harm score jointly demonstrate that this process is critical and necessary in preparing the voluntary reports for further content and semantics analysis.

  7. The mangled lower leg

    NARCIS (Netherlands)

    Hoogendoorn, Jochem Maarten

    2002-01-01

    A surgeon faced with a patient presenting with an open tibial/fibular fracture in combination with severe damage of the surrounding soft tissues, has to make the difficult decision whether to attempt salvage or to perform an immediate amputation of the leg. Until late in the nineteenth century the

  8. Leg med vision

    DEFF Research Database (Denmark)

    Munk, Mette; Bertelsen, Katrine

    2011-01-01

    alle med interesse for leg og bevægelse i daginstitutioner. Bogen er skrevet i et samarbejde mellem Ringsted Kommune og det nationale videncenter for sundhed, kost og motion for børn og unge, KOSMOS (www.vicekosmos.dk).Der er i samarbejde med to daginstitutioner indhentet vigtige og kvalificerede...

  9. Leg CT scan

    Science.gov (United States)

    ... x-ray beam rotates around you. (Modern "spiral" scanners can perform the exam without stopping.) A computer creates separate images of the body area, called slices. These images can be stored, viewed on a monitor, or printed on film. Three-dimensional (3D) models of the leg can be created by ...

  10. Leg design in hexapedal runners

    National Research Council Canada - National Science Library

    Full, R J; Blickhan, R; Ting, L H

    1991-01-01

    .... To explain how diverse leg designs can result in common whole-body dynamics, we used a miniature force platform to measure the ground reaction forces produced by individual legs of the cockroach Blaberus discoidalis...

  11. The Notion of Voluntary Unemployment.

    Science.gov (United States)

    Standing, Guy

    1981-01-01

    Considers the distinction between voluntary and involuntary unemployment by analyzing six behavioral characteristics attributed to groups of workers suspected of indulging in the former, and the labor market mechanisms supposedly encouraging them. (Author/CT)

  12. Leg strength is associated with ventilatory efficiency in older women.

    Science.gov (United States)

    Gonzales, J U; Tucker, S H; Kalasky, M J; Proctor, D N

    2012-07-01

    The aim of the present study was to determine if leg function is associated with ventilatory efficiency during exercise in healthy older adults. 24 women and 18 men aged 60-80 years performed treadmill exercise to fatigue for calculation of ventilatory efficiency using the ratio of ventilation to carbon dioxide at the anaerobic threshold (VE/VCO₂@AT). On a separate day, participants performed leg strength testing and graded single-leg knee extension exercise. The VE/VCO₂@AT was higher in women than men (33±3 vs. 30±3; p=0.03). After adjustment for age and VO(₂max), leg strength (knee extensor isometric force) was inversely associated with VE/VCO₂@AT in women (r= - 0.44, p=0.03) while no relationships were found for men. Strength-matched women and men had similar VE/VCO₂@AT indicating that the correlation between leg strength and VE/VCO₂@AT was strength- but not sex-specific. During knee extensor exercise, women with lower leg strength had increased VE/VCO₂ slope across 0-15 W as compared to higher strength women (38±8 vs. 31±3; p<0.05), while no differences were found for men. These results find leg strength to be associated with ventilatory responses to exercise in healthy older women, a finding that might be related to lower leg strength in women than men.

  13. A comparison of two gluteus maximus EMG maximum voluntary isometric contraction positions

    Directory of Open Access Journals (Sweden)

    Bret Contreras

    2015-09-01

    Full Text Available Background. The purpose of this study was to compare the peak electromyography (EMG of the most commonly-used position in the literature, the prone bent-leg (90° hip extension against manual resistance applied to the distal thigh (PRONE, to a novel position, the standing glute squeeze (SQUEEZE.Methods. Surface EMG electrodes were placed on the upper and lower gluteus maximus of thirteen recreationally active females (age = 28.9 years; height = 164 cm; body mass = 58.2 kg, before three maximum voluntary isometric contraction (MVIC trials for each position were obtained in a randomized, counterbalanced fashion.Results. No statistically significant (p < 0.05 differences were observed between PRONE (upper: 91.94%; lower: 94.52% and SQUEEZE (upper: 92.04%; lower: 85.12% for both the upper and lower gluteus maximus. Neither the PRONE nor SQUEEZE was more effective between all subjects.Conclusions. In agreement with other studies, no single testing position is ideal for every participant. Therefore, it is recommended that investigators employ multiple MVIC positions, when possible, to ensure accuracy. Future research should investigate a variety of gluteus maximus MVIC positions in heterogeneous samples.

  14. A comparison of two gluteus maximus EMG maximum voluntary isometric contraction positions.

    Science.gov (United States)

    Contreras, Bret; Vigotsky, Andrew D; Schoenfeld, Brad J; Beardsley, Chris; Cronin, John

    2015-01-01

    Background. The purpose of this study was to compare the peak electromyography (EMG) of the most commonly-used position in the literature, the prone bent-leg (90°) hip extension against manual resistance applied to the distal thigh (PRONE), to a novel position, the standing glute squeeze (SQUEEZE). Methods. Surface EMG electrodes were placed on the upper and lower gluteus maximus of thirteen recreationally active females (age = 28.9 years; height = 164 cm; body mass = 58.2 kg), before three maximum voluntary isometric contraction (MVIC) trials for each position were obtained in a randomized, counterbalanced fashion. Results. No statistically significant (p < 0.05) differences were observed between PRONE (upper: 91.94%; lower: 94.52%) and SQUEEZE (upper: 92.04%; lower: 85.12%) for both the upper and lower gluteus maximus. Neither the PRONE nor SQUEEZE was more effective between all subjects. Conclusions. In agreement with other studies, no single testing position is ideal for every participant. Therefore, it is recommended that investigators employ multiple MVIC positions, when possible, to ensure accuracy. Future research should investigate a variety of gluteus maximus MVIC positions in heterogeneous samples.

  15. ORTHOPEDIC LEG BRACE

    Science.gov (United States)

    Myers, William Neil (Inventor)

    2005-01-01

    Knee braces generally have been rigid in both the knee bending direction and in the knee straightening direction unless a manually operated release is incorporated in them to allow the knee to bend. Desirably a braced knee joint should effectively duplicate the compound, complex, actions of a normal knee. The key to knee braces is the knee joint housing. The housing herein carries a number of cam action pawls. with teeth adapted to engage the internal teeth of a ratchet ring mounted in the housing. Cam action return springs and the shape of the cam action pawl teeth allow rotation of the ratchet ring in a leg straightening direction while still supporting a load. The leg can then be extended during walking while at the same time being prevented by the cam action pawls from buckling in the knee bending direction.

  16. Restless legs syndrome.

    Science.gov (United States)

    Klingelhoefer, Lisa; Bhattacharya, Kalyan; Reichmann, Heinz

    2016-08-01

    Restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED), is a common movement disorder characterised by an uncontrollable urge to move because of uncomfortable, sometimes painful sensations in the legs with a diurnal variation and a release with movement. The pathophysiology is only partially known and a genetic component together with dopaminergic and brain iron dysregulation plays an important role. Secondary causes for RLS need to be excluded. Treatment depends on the severity and frequency of RLS symptoms, comprises non-pharmacological (eg lifestyle changes) and pharmacological interventions (eg dopaminergic medication, alpha-2-delta calcium channel ligands, opioids) and relieves symptoms only. Augmentation is the main complication of long-term dopaminergic treatment of RLS. This article will provide a clinically useful overview of RLS with provision of diagnostic criteria, differential diagnoses, possible investigations and different treatment strategies with their associated complications. © 2016 Royal College of Physicians.

  17. Venous Leg Ulcers.

    Science.gov (United States)

    Vivas, Alejandra; Lev-Tov, Hadar; Kirsner, Robert S

    2016-08-02

    This issue provides a clinical overview of venous leg ulcers, focusing on prevention, diagnosis, treatment, and practice improvement. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers.

  18. have a hollow leg

    Institute of Scientific and Technical Information of China (English)

    周立

    2003-01-01

    英语对话 A:We must prevent our family members from getting involved with drugs, really. B:That’s a sure thing.We must make sure that they never involve them- selves with that. A:By the way,does your husband drink a lot? B:Yeah.That’s the only thing that keeps worrying me.And he often boasts that he has a hollow leg and nobody can drink him under the ta- ble.

  19. Comparing Voluntary and Mandatory Gameplay

    Directory of Open Access Journals (Sweden)

    Esther Kuindersma

    2016-09-01

    Full Text Available Gameplay is commonly considered to be a voluntary activity. Game designers generally believe that voluntary gameplay is essentially different from mandatory gameplay. Such a belief may be a challenge for serious games, as instruction is usually mandatory. The article describes the outcomes of two experiments on the impact of voluntariness on the learning effect and enjoyment of a serious game. In the first experiment freedom of choosing to play a serious game was studied, with participants who had volunteered to participate. The results suggested that, contrary to the opinion of many game designers, being required to play a serious game does not automatically take the fun out of the game. The second experiment had voluntary participants and mandatory participants, who had to participate as part of a homework assignment. The outcomes show that mandatory participants enjoyed the game as much as the voluntary participants, even if they had to play the game for a minimum required time. These studies indicate that mandatory gameplay does not reduce enjoyment and learning effect.

  20. Voluntary organisation and adult education

    Directory of Open Access Journals (Sweden)

    Konrad Elsdon

    1998-12-01

    Full Text Available The author starts by offering a definition of voluntary organisations. He then discusses their importance and role, focusing on the issue of adult education wi­ thin these organisations. He also wells upon learning and change of voluntary organisation members, making use of the results of a study he conducted together with his collaborators. One of their fin­dings has been that voluntary organisati­ons, due to their organisational targets li­ke painting, singing or caring for people in need, lead their members to learning, i.e. essentially content learning. Moreo­ver, voluntary organisations offer a fair number of opportunities for social lear­ning and change. ln spite of the fact that the respondents were mostly not aware of the outcomes of their learning and change, careful listeners conducting the interview made them understand the im­portance of the learning they had gone through. The author concludes by poin­ ting out that formal education of adults can get its inspiration in learning in voluntary organisations. On the other hand, such learning would benefit greatly from findings and methods of formal education of adults.

  1. Voluntary activation of human knee extensors measured using transcranial magnetic stimulation.

    Science.gov (United States)

    Goodall, S; Romer, L M; Ross, E Z

    2009-09-01

    The aim of this study was to determine the applicability and reliability of a transcranial magnetic stimulation twitch interpolation technique for measuring voluntary activation of a lower limb muscle group. Cortical voluntary activation of the knee extensors was determined in nine healthy men on two separate visits by measuring superimposed twitch torques evoked by transcranial magnetic stimulation during isometric knee extensions of varying intensity. Superimposed twitch amplitude decreased linearly with increasing voluntary torque between 50 and 100% of mean maximal torque, allowing estimation of resting twitch amplitude and subsequent calculation of voluntary activation. There were no systematic differences for maximal voluntary activation within day (mean +/- s.d. 90.9 +/- 6.2 versus 90.7 +/- 5.9%; P = 0.98) or between days (90.8 +/- 6.0 versus 91.2 +/- 5.7%; P = 0.92). Systematic bias and random error components of the 95% limits of agreement were 0.23 and 9.3% within day versus 0.38 and 7.5% between days. Voluntary activation was also determined immediately after a 2 min maximal voluntary isometric contraction; in four of these subjects, voluntary activation was determined 30 min after the sustained contraction. Immediately after the sustained isometric contraction, maximal voluntary activation was reduced from 91.2 +/- 5.7 to 74.2 +/- 12.0% (P knee extensors.

  2. Differential diagnosis of leg ulcers.

    Science.gov (United States)

    Pannier, F; Rabe, E

    2013-03-01

    Leg and foot ulcers are symptoms of very different diseases. The aim of this paper is to demonstrate the differential diagnosis of leg ulcers. The majority of leg ulcers occur in the lower leg or foot. In non-venous ulcers the localization in the foot area is more frequent. The most frequent underlying disease is chronic venous disease. In 354 leg ulcers, Koerber found 75.25% venous leg ulcers, 3.66% arterial leg ulcers, 14.66% ulcers of mixed venous and arterial origin and 13.5% vasculitic ulcers. In the Swedish population of Skaraborg, Nelzen found a venous origin in 54% of the ulcer patients. Each leg ulcer needs a clinical and anamnestic evaluation. Duplex ultrasound is the basic diagnostic tool to exclude vascular anomalies especially chronic venous and arterial occlusive disease. Skin biopsies help to find a correct diagnosis in unclear or non-healing cases. In conclusion, chronic venous disease is the most frequent cause of leg ulcerations. Because 25% of the population have varicose veins or other chronic venous disease the coincidence of pathological venous findings and ulceration is very frequent even in non-venous ulcerations. Leg ulcers without the symptoms of chronic venous disease should be considered as non-venous.

  3. Leg cramps and restless legs syndrome during pregnancy.

    Science.gov (United States)

    Hensley, Jennifer G

    2009-01-01

    Sleep disturbance during pregnancy can result in excessive daytime sleepiness, diminished daytime performance, inability to concentrate, irritability, and the potential for an increased length of labor and increased risk of operative birth. Sleep disturbance may be the result of a sleep disorder, such as leg cramps, a common yet benign disorder, or restless legs syndrome, a sensorimotor disorder. Both disrupt sleep, are distressing to the pregnant woman, and mimic one another and other serious disorders. During pregnancy, up to 30% of women can be affected by leg cramps, and up to 26% can be affected by restless legs syndrome.

  4. Textiloma in the leg

    Directory of Open Access Journals (Sweden)

    Patel Amol

    2007-01-01

    Full Text Available Textiloma is defined as a tumor formed due to retained gauze. It is rarely reported in the musculoskeletal system. We are presenting a case with a soft tissue swelling over the lateral aspect of the lower third of the leg, come for implant removal of the distal tibia and fibular fracture. We removed the soft tissue mass enbloc thinking it to be a benign tumor. On cutting the mass on the operation table, a gauze piece encased by fibrous tissue was found. Textiloma can present as tumoral forms and can mimic as a pseudo-tumor.

  5. The effect of spinal manipulation on imbalances in leg strength.

    Science.gov (United States)

    Chilibeck, Philip D; Cornish, Stephen M; Schulte, Al; Jantz, Nathan; Magnus, Charlene R A; Schwanbeck, Shane; Juurlink, Bernhard H J

    2011-09-01

    We hypothesized that spinal manipulation (SM) would reduce strength imbalances between legs. Using an un-blinded randomized design, 28 males and 21 females (54 ± 19y) with at least a 15% difference in isometric strength between legs for hip flexion, extension, abduction, or knee flexion were randomized to treatment or placebo (mock spinal manipulation). Strength of the stronger and weaker legs for hip flexion, extension, abduction, and/or knee flexion was assessed before and after the intervention. SM reduced the relative strength difference between legs for knee flexion (mean ± SD 57 ± 53 to 5 ± 14%) and hip flexion (24 ± 12 to 11 ± 15%) compared to placebo (34 ± 29 to 24 ± 36%, and 20 ± 18 to 22 ± 26%, respectively) (p = 0.05). SM also improved strength in the weak leg for hip abduction (104 ± 43 to 116 ± 43 Nm) compared to placebo (84 ± 24 to 85 ± 31 Nm) (p = 0.03). This study suggests that spinal manipulation may reduce imbalances in strength between legs for knee and hip flexion.

  6. Emphysematous Pyelonephritis Presenting as Necrotizing Fasciitis of the Leg

    Directory of Open Access Journals (Sweden)

    Yu-Xiong Ye

    2009-03-01

    Full Text Available We report a 50-year-old man with poorly controlled diabetes mellitus who presented with a painful, swollen right leg. He had also experienced right flank pain for 1 week prior to admission. Physical examination was notable for tenderness over the right flank. The right leg was diffusely swollen and exquisitely tender to touch, with palpable crepitance. Laboratory tests revealed leukocytosis and pyuria. Computed tomography showed a right ureteral stone with hydronephrosis and characteristic findings of emphysematous pyelonephritis. Furthermore, a right perirenal gas-forming abscess with extension to the right leg was noted. The patient was successfully treated with antibiotic therapy, aggressive control of blood sugar, percutaneous drainage of the hydronephrosis and perirenal abscess, and aggressive debridement of the leg.

  7. Voluntary euthanasia: a utilitarian perspective.

    Science.gov (United States)

    Singer, Peter

    2003-10-01

    Belgium legalised voluntary euthanasia in 2002, thus ending the long isolation of the Netherlands as the only country in which doctors could openly give lethal injections to patients who have requested help in dying. Meanwhile in Oregon, in the United States, doctors may prescribe drugs for terminally ill patients, who can use them to end their life--if they are able to swallow and digest them. But despite President Bush's oft-repeated statements that his philosophy is to 'trust individuals to make the right decisions' and his opposition to 'distant bureaucracies', his administration is doing its best to prevent Oregonians acting in accordance with a law that its voters have twice ratified. The situation regarding voluntary euthanasia around the world is therefore very much in flux. This essay reviews ethical arguments regarding voluntary euthanasia and physician-assisted suicide from a utilitarian perspective. I shall begin by asking why it is normally wrong to kill an innocent person, and whether these reasons apply to aiding a person who, when rational and competent, asks to be killed or given the means to commit suicide. Then I shall consider more specific utilitarian arguments for and against permitting voluntary euthanasia.

  8. Social Cohesion and Voluntary Associations

    Science.gov (United States)

    Heuser, Brian L.

    2005-01-01

    Voluntary organizations exert great influence over how social norms and ethical codes are guided into action. As such, they have a significant impact on societal levels of social cohesion. Although social capital involves generalized trust becoming manifest as spontaneous sociability, social cohesion is determined by how that sociability is…

  9. Voluntary Incentive Early Retirement Programs.

    Science.gov (United States)

    Research Dialogues, 1988

    1988-01-01

    Arrangements in educational institutions for voluntary early retirement programs are discussed. Retirement at any age can be a profound and stressful lifetime change; and it can also represent a welcome transition into newly satisfying and rewarding opportunities. The focus is on: mandatory retirement (exceptions and the new meaning of "early");…

  10. Voluntary disclosure: Evidence from UK

    NARCIS (Netherlands)

    N.S. Zourarakis (Nicolaos)

    2009-01-01

    textabstractThis paper investigates the voluntary disclosure of Intellectual Capital (IC) of British firms and provides some evidence on an unexplored area of the literature; that of the association of Corporate Governance (CG) with IC disclosure. Inconsistent with expectations, the results show tha

  11. Optimal load balancing leveling method for multi-leg flexible platforms

    Science.gov (United States)

    Gang, Xianyue; Chai, Shan

    2013-09-01

    The working platforms supported with multiple extensible legs must be leveled before they come into operation. Although the supporting stiffness and reliability of the platform are improved with the increasing number of the supporting legs, the increased overdetermination of the multi-leg platform systems leads to leveling coupling problem among legs and virtual leg problem in which some of the supporting legs bear zero or quasi zero loads. These problems make it quite complex and time consuming to level such a multi-leg platform. Based on rigid body kinematics, an approximate equation is formulated to rapidly calculate the leg extension for leveling a rigid platform, then a proportional speed control strategy is proposed to reduce the unexpected platform distortion and leveling coupling between supporting legs. Taking both the load coupling between supporting legs and the elastic flexibility of the working platform into consideration, an optimal balancing legs’ loads(OBLL) model is firstly put forward to deal with the traditional virtual leg problem. By taking advantage of the concept of supporting stiffness matrix, a coupling extension method(CEM) is developed to solve this OBLL problem for multi-leg flexible platform. At the end, with the concept of supporting stiffness matrix and static transmissibility matrix, an optimal load balancing leveling method is proposed to achieve geometric leveling and legs’ loads balancing simultaneously. Three numerical examples are given out to illustrate the performance of proposed methods. This paper proposes a method which can effectively quantify all of the legs’ extension at the same time, achieve geometric leveling and legs’ loads balancing simultaneously. By using the proposed methods, the stability, precision and efficiency of auto-leveling control process can be improved.

  12. Voluntary sterilization in Serbia: Unmet need?

    OpenAIRE

    Rašević Mirjana M.

    2002-01-01

    Is voluntary sterilization as a birth control method accepted in Serbia? This is certainly a question that is being imposed for research, regardless of the fact that voluntary sterilization is neither accessible nor promoted. Most importantly because there is no understanding in the social nor political sphere for legalization of voluntary sterilization as a form of birth control, apart from the clear necessity for this, first, step. They are: the recognition that voluntary sterilization is a...

  13. Differentiating nocturnal leg cramps and restless legs syndrome.

    Science.gov (United States)

    Rana, Abdul Qayyum; Khan, Fatima; Mosabbir, Abdullah; Ondo, William

    2014-07-01

    Leg pain and discomfort are common complaints in any primary physician's clinic. Two common causes of pain or discomfort in legs are nocturnal leg cramps (NLC) and restless leg syndrome (RLS). NLC present as painful and sudden contractions mostly in part of the calf. Diagnosis of NLC is mainly clinical and sometimes involves investigations to rule out other mimics. RLS is a condition characterized by the discomfort or urge to move the lower limbs, which occurs at rest or in the evening/night. The similarity of RLS and leg cramps poses the issue of errors in diagnosing and differentiating the two. In this paper we review the pathopysiology of each entity and their diagnosis as well as treatment. The two conditions are then compared to appreciate the differences and similarities. Finally, suggestions are recommended for complete assessment.

  14. [Restless-legs syndrome].

    Science.gov (United States)

    Karroum, E; Konofal, E; Arnulf, I

    2008-01-01

    Restless-legs syndrome (RLS) is a sensorimotor disorder, characterized by an irresistible urge to move the legs usually accompanied or caused by uncomfortable and unpleasant sensations. It begins or worsens during periods of rest or inactivity, is partially or totally relieved by movements and is exacerbated or occurs at night and in the evening. RLS sufferers represent 2 to 3% of the general population in Western countries. Supportive criteria include a family history, the presence of periodic-leg movements (PLM) when awake or asleep and a positive response to dopaminergic treatment. The RLS phenotypes include an early onset form, usually idiopathic with a familial history and a late onset form, usually secondary to peripheral neuropathy. Recently, an atypical RLS phenotype without PLM and l-DOPA resistant has been characterized. RLS can occur in childhood and should be distinguished from attention deficit/hyperactivity disorder, growing pains and sleep complaints in childhood. RLS should be included in the diagnosis of all patients consulting for sleep complaints or discomfort in the lower limbs. It should be differentiated from akathisia, that is, an urge to move the whole body without uncomfortable sensations. Polysomnographic studies and the suggested immobilization test can detect PLM. Furthermore, an l-DOPA challenge has recently been validated to support the diagnosis of RLS. RLS may cause severe-sleep disturbances, poor quality of life, depressive and anxious symptoms and may be a risk factor for cardiovascular disease. In most cases, RLS is idiopathic. It may also be secondary to iron deficiency, end-stage renal disease, pregnancy, peripheral neuropathy and drugs, such as antipsychotics and antidepressants. The small-fiber neuropathy can mimic RLS or even trigger it. RLS is associated with many neurological and sleep disorders including Parkinson's disease, but does not predispose to these diseases. The pathophysiology of RLS includes an altered brain

  15. A Model for Evaluating eXtension Communities of Practice

    Science.gov (United States)

    Kelsey, Kathleen D.; Stafne, Eric T.

    2012-01-01

    As Americans shift their work and leisure activities online, Extension seeks to remain viable by delivering programs through a website known as eXtension. eXtension is predicated on the voluntary labor of Extension specialists and educators who form Communities of Practice to create and deliver content through the website. Evaluation of eXtension…

  16. 22 CFR 513.210 - Voluntary exclusion.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Voluntary exclusion. 513.210 Section 513.210... GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (GRANTS) Effect of Action § 513.210 Voluntary exclusion. Persons who accept voluntary exclusions under § 513.315 are excluded in accordance with the terms of...

  17. Myonecrosis in the leg caused by Salmonella enteritidis

    DEFF Research Database (Denmark)

    Jørring, S; Kolmos, H J; Klareskov, B

    1994-01-01

    Five weeks after an episode of gastroenteritis, a 65-year-old diabetic male developed an extensive myonecrosis, with gas production in the left leg caused by Salmonella enteritidis. The patient was treated with surgical revision and antibiotics. To our knowledge, this is the first case of myonecr......Five weeks after an episode of gastroenteritis, a 65-year-old diabetic male developed an extensive myonecrosis, with gas production in the left leg caused by Salmonella enteritidis. The patient was treated with surgical revision and antibiotics. To our knowledge, this is the first case...... of myonecrosis with gas production in a leg caused by Salmonella enteritidis, in which the patient survived, and the limb was saved....

  18. Klinefelter Syndrome With Leg Ulcers

    Directory of Open Access Journals (Sweden)

    Narendra G

    1999-01-01

    Full Text Available Leg ulcers are frequently caused by venous insufficiency, arterial insufficiency, neuropathy, or a combination of these factors. Klinefelter syndrome in association with chronic leg ulcers have been reported earlier. We report a case of Klinefelter syndrome with non- healing ulcer. The diagnosis of the Klinefelter syndrome was confirmed by karyotyping.

  19. The Acute Compartment Syndrome of the Lower Leg: A Difficult Diagnosis?

    NARCIS (Netherlands)

    J. Vlot; M.G. Eversdijk (Martin); D. den Hartog (Dennis); P.P. Oprel (Pim); W.E. Tuinebreijer (Wim)

    2010-01-01

    textabstractThree patients, two adults and one child, developed an acute compartment syndrome of the lower leg. Due to delay in diagnosis, severe complications developed, resulting in two transfemoral amputations. In the youngest patient, the lower leg was able to be saved after extensive reconstruc

  20. The Acute Compartment Syndrome of the Lower Leg: A Difficult Diagnosis?

    NARCIS (Netherlands)

    J. Vlot; M.G. Eversdijk (Martin); D. den Hartog (Dennis); P.P. Oprel (Pim); W.E. Tuinebreijer (Wim)

    2010-01-01

    textabstractThree patients, two adults and one child, developed an acute compartment syndrome of the lower leg. Due to delay in diagnosis, severe complications developed, resulting in two transfemoral amputations. In the youngest patient, the lower leg was able to be saved after extensive

  1. International Voluntary Renewable Energy Markets (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Heeter, J.

    2012-06-01

    This presentation provides an overview of international voluntary renewable energy markets, with a focus on the United States and Europe. The voluntary renewable energy market is the market in which consumers and institutions purchase renewable energy to match their electricity needs on a voluntary basis. In 2010, the U.S. voluntary market was estimated at 35 terawatt-hours (TWh) compared to 300 TWh in the European market, though key differences exist. On a customer basis, Australia has historically had the largest number of customers, pricing for voluntary certificates remains low, at less than $1 megawatt-hour, though prices depend on technology.

  2. Genetics Home Reference: restless legs syndrome

    Science.gov (United States)

    ... Johns Hopkins Medicine MalaCards: restless legs syndrome Merck Manual Professional Version Patient Support and Advocacy Resources (3 links) European Alliance for Restless Legs Syndrome National Organization for Rare Disorders (NORD) Restless Leg Syndrome Foundation ...

  3. Twitch potentiation induced by stimulated and voluntary isometric contractions at various torque levels in human knee extensor muscles.

    Science.gov (United States)

    Miyamoto, Naokazu; Yanai, Toshimasa; Kawakami, Yasuo

    2011-03-01

    The purpose of this study was to compare the extent of twitch potentiation (TP) after stimulated or voluntary contractions at identical intensities for the human knee extensor muscles. Isometric knee extensions of 10 s were performed at 20%, 40%, and 60% of maximal voluntary contraction (MVC) torque level, through percutaneous electrical stimulation of the quadriceps at 80 Hz or voluntary contraction. Twitch responses were evoked by stimulating the femoral nerve percutaneously with supramaximal intensity. The extent of TP after the stimulated contraction was greater than that after the voluntary contraction at the 20% MVC torque level, whereas a stimulated contraction induced a smaller extent of TP than did a voluntary contraction at contraction intensities higher than 40% MVC. We suggest that this contraction intensity dependence of differences in TP after stimulated and voluntary isometric conditioning contractions is responsible for differences in the recruitment pattern of motor units during the conditioning contractions.

  4. Lower extremity extension force and electromyography properties as a function of knee angle and their relation to joint torques: implications for strength diagnostics.

    Science.gov (United States)

    Hahn, Daniel

    2011-06-01

    The purpose of this study was to evaluate whether and how isometric multijoint leg extension strength can be used to assess athletes' muscular capability within the scope of strength diagnosis. External reaction forces (Fext) and kinematics were measured (n = 18) during maximal isometric contractions in a seated leg press at 8 distinct joint angle configurations ranging from 30 to 100° knee flexion. In addition, muscle activation of rectus femoris, vastus medialis, biceps femoris c.l., gastrocnemius medialis, and tibialis anterior was obtained using surface electromyography (EMG). Joint torques for hip, knee, and ankle joints were computed by inverse dynamics. The results showed that unilateral Fext decreased significantly from 3,369 ± 575 N at 30° knee flexion to 1,015 ± 152 N at 100° knee flexion. Despite maximum voluntary effort, excitation of all muscles as measured by EMG root mean square changed with knee flexion angles. Moreover, correlations showed that above-average Fext at low knee flexion is not necessarily associated with above-average Fext at great knee flexion and vice versa. Similarly, it is not possible to deduce high joint torques from high Fext just as above-average joint torques in 1 joint do not signify above-average torques in another joint. From these findings, it is concluded that an evaluation of muscular capability by means of Fext as measured for multijoint leg extension is strongly limited. As practical recommendation, we suggest analyzing multijoint leg extension strength at 3 distinct knee flexion angles or at discipline-specific joint angles. In addition, a careful evaluation of muscular capacity based on measured Fext can be done for knee flexion angles ≥ 80°. For further and detailed analysis of single muscle groups, the use of inverse dynamic modeling is recommended.

  5. A biological micro actuator: graded and closed-loop control of insect leg motion by electrical stimulation of muscles.

    Science.gov (United States)

    Cao, Feng; Zhang, Chao; Vo Doan, Tat Thang; Li, Yao; Sangi, Daniyal Haider; Koh, Jie Sheng; Huynh, Ngoc Anh; Bin Aziz, Mohamed Fareez; Choo, Hao Yu; Ikeda, Kazuo; Abbeel, Pieter; Maharbiz, Michel M; Sato, Hirotaka

    2014-01-01

    In this study, a biological microactuator was demonstrated by closed-loop motion control of the front leg of an insect (Mecynorrhina torquata, beetle) via electrical stimulation of the leg muscles. The three antagonistic pairs of muscle groups in the front leg enabled the actuator to have three degrees of freedom: protraction/retraction, levation/depression, and extension/flexion. We observed that the threshold amplitude (voltage) required to elicit leg motions was approximately 1.0 V; thus, we fixed the stimulation amplitude at 1.5 V to ensure a muscle response. The leg motions were finely graded by alternation of the stimulation frequencies: higher stimulation frequencies elicited larger leg angular displacement. A closed-loop control system was then developed, where the stimulation frequency was the manipulated variable for leg-muscle stimulation (output from the final control element to the leg muscle) and the angular displacement of the leg motion was the system response. This closed-loop control system, with an optimized proportional gain and update time, regulated the leg to set at predetermined angular positions. The average electrical stimulation power consumption per muscle group was 148 µW. These findings related to and demonstrations of the leg motion control offer promise for the future development of a reliable, low-power, biological legged machine (i.e., an insect-machine hybrid legged robot).

  6. A biological micro actuator: graded and closed-loop control of insect leg motion by electrical stimulation of muscles.

    Directory of Open Access Journals (Sweden)

    Feng Cao

    Full Text Available In this study, a biological microactuator was demonstrated by closed-loop motion control of the front leg of an insect (Mecynorrhina torquata, beetle via electrical stimulation of the leg muscles. The three antagonistic pairs of muscle groups in the front leg enabled the actuator to have three degrees of freedom: protraction/retraction, levation/depression, and extension/flexion. We observed that the threshold amplitude (voltage required to elicit leg motions was approximately 1.0 V; thus, we fixed the stimulation amplitude at 1.5 V to ensure a muscle response. The leg motions were finely graded by alternation of the stimulation frequencies: higher stimulation frequencies elicited larger leg angular displacement. A closed-loop control system was then developed, where the stimulation frequency was the manipulated variable for leg-muscle stimulation (output from the final control element to the leg muscle and the angular displacement of the leg motion was the system response. This closed-loop control system, with an optimized proportional gain and update time, regulated the leg to set at predetermined angular positions. The average electrical stimulation power consumption per muscle group was 148 µW. These findings related to and demonstrations of the leg motion control offer promise for the future development of a reliable, low-power, biological legged machine (i.e., an insect-machine hybrid legged robot.

  7. Restless legs syndrome: literature review

    Directory of Open Access Journals (Sweden)

    Emmanouil Symvoulakis

    Full Text Available Restless legs syndrome is a distressing condition, with negative effects on sleep and daytime activities that affect personal, family and occupational life. The overall impact of restless legs syndrome on quality of life is comparable to that of chronic and frustrating conditions such as depression and diabetes. Misdiagnosis and inappropriate treatment may increase patients' suffering in terms of uncertainty, overuse or misuse of care services and lack of trust. Presenting a synthesis of the main topics in the literature on restless legs syndrome facilitates for a better understanding and its management in primary care settings.

  8. Man with leg rash.

    Science.gov (United States)

    Hwang, Michael Huynh; Khesbak, Ziyad; Liu, Yiju Teresa

    2017-10-01

    A 51-year-old male presented to the ED with a rash to his left thigh (figure 1) with erythema, swelling and pain. He endorsed paraesthesias, pruritus, fevers, vomiting and diarrhoea. Initial vitals were unremarkable. He was well appearing with an 8×8 cm violaceous patch on his left medial thigh with vesicles, surrounding erythema and induration with a second, smaller lesion on the right thigh. Both rashes were extremely tender.emermed;34/10/686/F1F1F1Figure 1Erythematosus and vesicular rash in bilateral legs.A bedside ultrasound image of the rash was obtained (figure 2).emermed;34/10/686/F2F2F2Figure 2Bedside ultrasound of rash. What is the most likely cause of the patient's rash?A. Herpes zosterB. CellulitisC. Necrotising fasciitisD. Bullous pemphigoid. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  9. Leg-adjustment strategies for stable running in three dimensions.

    Science.gov (United States)

    Peuker, Frank; Maufroy, Christophe; Seyfarth, André

    2012-09-01

    The dynamics of the center of mass (CoM) in the sagittal plane in humans and animals during running is well described by the spring-loaded inverted pendulum (SLIP). With appropriate parameters, SLIP running patterns are stable, and these models can recover from perturbations without the need for corrective strategies, such as the application of additional forces. Rather, it is sufficient to adjust the leg to a fixed angle relative to the ground. In this work, we consider the extension of the SLIP to three dimensions (3D SLIP) and investigate feed-forward strategies for leg adjustment during the flight phase. As in the SLIP model, the leg is placed at a fixed angle. We extend the scope of possible reference axes from only fixed horizontal and vertical axes to include the CoM velocity vector as a movement-related reference, resulting in six leg-adjustment strategies. Only leg-adjustment strategies that include the CoM velocity vector produced stable running and large parameter domains of stability. The ability of the model to recover from perturbations along the direction of motion (directional stability) depended on the strategy for lateral leg adjustment. Specifically, asymptotic and neutral directional stability was observed for strategies based on the global reference axis and the velocity vector, respectively. Additional features of velocity-based leg adjustment are running at arbitrary low speed (kinetic energy) and the emergence of large domains of stable 3D running that are smoothly transferred to 2D SLIP stability and even to 1D SLIP hopping. One of the additional leg-adjustment strategies represented a large convex region of parameters where stable and robust hopping and running patterns exist. Therefore, this strategy is a promising candidate for implementation into engineering applications, such as robots, for instance. In a preliminary comparison, the model predictions were in good agreement with the experimental data, suggesting that the 3D SLIP is an

  10. [Restless legs syndrome - a review].

    Science.gov (United States)

    Sveinsson, Olafur Arni; Sigurdsson, Albert Pall

    2012-01-01

    Restless legs syndrome (RLS) is a common disorder with a prevalence between 10-20% in Iceland. There are two forms of RLS, idiopathic and secondary. Symptom onset of RLS before the age of 45 suggests an idiopathic form with no known underlying cause but inheritance. Symptom onset after age of 45 indicates a secondary form with an underlying cause without inheritance. Causes for secondary forms are for example: iron depletion, uraemia and polyneuropathy. Symptoms of RLS are uncomfortable and unpleasant deep sensations in the legs that are felt at rest, accompanied by an urge to move the legs, typically just before sleep. Accompanying RLS is a sleep disturbance that can lead to daytime somnolence, decreased quality of life, poor concentration, memory problems, depression and decreased energy. Dopamine agonists are currently the first line treatment for RLS. restless legs, periodic limb movements, sleep disturbance, dopamine agonists.

  11. Restless leg syndrome in pregnancy.

    Science.gov (United States)

    Grover, Aarti; Clark-Bilodeau, Courtney; D'Ambrosio, Carolyn M

    2015-09-01

    Restless leg syndrome, more recently renamed Willis-Ekbom disease, is a condition that disrupts sleep and occurs more frequently in the pregnant population. We present a 39-year-old woman with restless legs syndrome in the third trimester and discuss the epidemiology, pathophysiology and therapeutic options in the pregnant population while highlighting the challenges posed by the lack of safety data of approved drugs.

  12. Botulinum toxin injection improved voluntary motor control in selected patients with post-stroke spasticity

    Institute of Scientific and Technical Information of China (English)

    Shuo-Hsiu Chang; Gerald E Francisco; Sheng Li

    2012-01-01

    The effect of botulinum toxin type A injection on voluntary grip control was examined in a 53-year-old female, who sustained a hemorrhagic right middle cerebral artery stroke 3 years previously, which resulted in finger flexor spasticity and residual weak finger/wrist extension. The patient received 50 units of botulinum toxin type A injection each to the motor points (2 sites/muscle) of the left flexor digitorum superficialis and flexor digitorum profundus, respectively. Botulinum toxin injection led to weakness and tone reduction in the spastic finger flexors, but improved grip release time in grip initiation/release reaction time tasks. Improved release time was accompanied by shortened extensor electromyography activity, and improved release time likely correlated with blocked co-contraction of finger flexors during voluntary finger extension. This case report demonstrated that botulinum toxin injection improved voluntary motor control of the hand in a chronic stroke patient with residual finger extension.

  13. Restless legs syndrome.

    Science.gov (United States)

    Miletić, Vladimir; Relja, Maja

    2011-12-01

    Being of the most frequent causes of insomnia, which in the end leads to chronic fatigue, inadequate performance of daily activities, and serious disruption of quality of living, restless legs syndrome (RLS) is nowadays not only a serious medical problem but a socio-economical one as well. Prevalence of the disorder in general population is estimated at 5 to 15%. Family history is positive in over 50% of idiopathic RLS patients which points to genetic basis of the disorder. The characteristics of the secondary or acquired form of RLS are symptoms that start later in life as well as a rapid progression of the disease. On the other hand, idiopathic RLS more often starts at a younger age and the prognoses are better. Over twenty disorders and conditions are brought in connection with secondary RLS. Although the cause of primary RLS is still unknown, there is a strong connection between central metabolism of iron as well as dopamine levels and RLS manifestation. A differential diagnosis of RLS includes a wide specter of motor and sensory disorders. Diagnosis is based on clinical features and the history of disease. To correctly diagnose idiopathic RLS one must first eliminate secondary causes of RLS and then also exclude any disorders with clinical features that mimic those of RLS. It has been estimated that some 20 to 25% of patients need pharmacological therapy. Best initial therapy is the application of nonergot dopamine agonists. Anticonvulsants, benzodiazepines and opioides can be given to patients who are refractory to dopaminergic therapy, those suffering from RLS with emphasized painful sensory component and those with RLS connected with insomnia.

  14. Intrinsic muscle strength and voluntary activation of both lower limbs and functional performance after stroke.

    Science.gov (United States)

    Horstman, Astrid M; Beltman, Marijke J; Gerrits, Karin H; Koppe, Peter; Janssen, Thomas W; Elich, Peter; de Haan, Arnold

    2008-07-01

    The objective of this study was to assess the nature of muscle weakness in both legs after stroke compared with able-bodied control individuals and to examine whether there is a relationship between the degree of muscle weakness and coactivation of knee extensors and flexors as well as voluntary activation capacity of knee extensors of both paretic and non-paretic legs and indices of functional performance. Maximal voluntary isometric torques of knee extensors (MVCe) and flexors (MVCf) were determined in 14 patients (bilaterally) and 12 able-bodied controls. Simultaneous measurements were made of torque and surface EMG from agonist and antagonist muscles. Coactivation was calculated. Supramaximal triplets were evoked with electrical stimulation to estimate maximal torque capacity and degree of voluntary activation of knee extensors. MVCs, activation and coactivation parameters were correlated to scores of seven functional performance tests. MVCe, MVCf and voluntary activation were lower in paretic lower limb (PL) compared with both non-paretic lower limb (NL) and control. Besides, all these parameters of NL were also lower than control. Electrically evoked torque capacity of knee extensors of PL was about 60% of both NL and control, which were not significantly different from each other. Strong significant correlations between strength, as well as voluntary activation, and functional performance were found. Coactivation did not correlate well with functional performance. Thus, whereas for NL activation failure can explain weakness, for PL both activation failure and reduced intrinsic torque capacity are responsible for the severe weakness. Activation capacity and muscle strength correlated strongly to functional performance, while coactivation did not.

  15. Unilateral eccentric contraction of the plantarflexors leads to bilateral alterations in leg dexterity

    Directory of Open Access Journals (Sweden)

    Akira Nagamori

    2016-11-01

    Full Text Available Eccentric contractions can affect musculotendon mechanical properties and disrupt muscle proprioception, but their behavioral consequences are poorly understood. We tested whether repeated eccentric contractions of plantarflexor muscles of one leg affected the dexterity of either leg. Twenty healthy male subjects (27.3+/-4.0 yrs compressed a compliant and slender spring prone to buckling with each isolated leg. The maximal instability they could control (i.e., the maximal average sustained compression force, or lower extremity dexterity force, LEDForce quantified the dexterity of each leg. We found that eccentric contractions did not affect LEDForce, but reduced force variability (LEDSD. Surprisingly, LEDForce increased in the non-exposed, contralateral leg. These effects were specific to exposure to eccentric contractions because an effort-matched exposure to walking did not affect leg dexterity. In the exposed leg, eccentric contractions (i reduced voluntary error corrections during spring compressions (i.e., reduced 0.5-4 Hz power of LEDForce; (ii did not change spinal excitability (i.e., unaffected H-reflexes; and (iii changed the structure of the neural drive to the alpha-motoneuron pool (i.e., reduced EMG power within the 4-8 Hz physiological tremor band. These results suggest that repeated eccentric contractions alter the feedback control for dexterity in the exposed leg by reducing muscle spindle sensitivity. Moreover, the unexpected improvement in LEDForce in the non-exposed contralateral leg was likely a consequence of crossed-effects on its spinal and supraspinal feedback control. We discuss the implications of these bilateral effects of unilateral eccentric contractions, their effect on spinal and supraspinal control of dynamic foot-ground interactions, and their potential to facilitate rehabilitation from musculoskeletal and neuromotor impairments.

  16. Differences in twitch potentiation between voluntary and stimulated quadriceps contractions of equal intensity.

    Science.gov (United States)

    Jubeau, M; Gondin, J; Martin, A; Van Hoecke, J; Maffiuletti, N A

    2010-02-01

    This study compared the extent of twitch and M-wave potentiation (POT) between voluntary and stimulated quadriceps contractions performed at the same intensity. Sixteen healthy men completed 10-s isometric knee extensions at 40% of the maximal voluntary contraction torque under electrical stimulation and voluntary conditions. Single stimuli were delivered to the femoral nerve to evoke twitches before (PRE) and from 3 to 600 s after the end of each conditioning contraction. Changes in twitch contractile properties and M-wave characteristics were compared between the conditions. The extent of twitch peak torque POT was smaller for the stimulated (122+/-20% of PRE) than for the voluntary condition (133+/-20% of PRE). The magnitude of POT for the maximal rate of twitch torque development was also smaller for the stimulated trial. Rectus femoris M-wave amplitude was potentiated by the voluntary but not by the stimulated contraction. It was concluded that stimulated contractions resulted in smaller twitch and M-wave POT than voluntary contractions, despite equivalent torque output and duration. The spatially and temporally fixed recruitment of motor units with electrical stimulation and therefore the lower number of activated motor units compared with voluntary actions of equal intensity could explain the present findings.

  17. 78 FR 49382 - Voluntary Education Programs

    Science.gov (United States)

    2013-08-14

    ... English, reading, writing, speaking, mathematics, and computer skills that are essential to successful job... education advisor: Education Services Specialist, Education Services Officer (ESO), Voluntary...

  18. Restless Legs Syndrome and Leg Motor Restlessness in Parkinson's Disease

    Science.gov (United States)

    Miyamoto, Masayuki; Miyamoto, Tomoyuki; Hirata, Koichi

    2015-01-01

    Sleep disturbances are important nonmotor symptoms in Parkinson's disease (PD) that are associated with a negative impact on quality of life. Restless legs syndrome (RLS), which is characterized by an urge to move the legs accompanied by abnormal leg sensations, can coexist with PD, although the pathophysiology of these disorders appears to be different. RLS and PD both respond favorably to dopaminergic treatment, and several investigators have reported a significant relationship between RLS and PD. Sensory symptoms, pain, motor restlessness, akathisia, and the wearing-off phenomenon observed in PD should be differentiated from RLS. RLS in PD may be confounded by chronic dopaminergic treatment; thus, more studies are needed to investigate RLS in drug-naïve patients with PD. Recently, leg motor restlessness (LMR), which is characterized by an urge to move the legs that does not fulfill the diagnostic criteria for RLS, has been reported to be observed more frequently in de novo patients with PD than in age-matched healthy controls, suggesting that LMR may be a part of sensorimotor symptoms intrinsic to PD. In this paper, we provide an overview of RLS, LMR, and PD and of the relationships among these disorders. PMID:26504610

  19. Dynamics of Voluntary Cough Maneuvers

    Science.gov (United States)

    Naire, Shailesh

    2008-11-01

    Voluntary cough maneuvers are characterized by transient peak expiratory flows (PEF) exceeding the maximum expiratory flow-volume (MEFV) curve. In some cases, these flows can be well in excess of the MEFV, generally referred to as supramaximal flows. Understanding the flow-structure interaction involved in these maneuvers is the main goal of this work. We present a simple theoretical model for investigating the dynamics of voluntary cough and forced expiratory maneuvers. The core modeling idea is based on a 1-D model of high Reynolds number flow through flexible-walled tubes. The model incorporates key ingredients involved in these maneuvers: the expiratory effort generated by the abdominal and expiratory muscles, the glottis and the flexibility and compliance of the lung airways. Variations in these allow investigation of the expiratory flows generated by a variety of single cough maneuvers. The model successfully reproduces PEF which is shown to depend on the cough generation protocol, the glottis reopening time and the compliance of the airways. The particular highlight is in simulating supramaximal PEF for very compliant tubes. The flow-structure interaction mechanisms behind these are discussed. The wave speed theory of flow limitation is used to characterize the PEF. Existing hypotheses of the origin of PEF, from cough and forced expiration experiments, are also tested using this model.

  20. Quantitation of progressive muscle fatigue during dynamic leg exercise in humans

    DEFF Research Database (Denmark)

    Fulco, C S; Lewis, S F; Frykman, Peter

    1995-01-01

    to quadriceps femoris. The slope of the linear relationship between O2 uptake and work rate was 13.7 ml O2/W (r = 0.93). This slope and the increase of heart rate relative to increasing work intensity agreed with published values for D leg exercise. Test-retest values for O2 uptake were similar (P > 0...... (*P rates). Virtually identical declines in MVC were observed by the end of graded work rate DKE and submaximal constant work rate DKE tests. Quantitation of progressive muscle fatigue during D leg exercise provides a framework to study the effects of a variety......There is virtually no published information on muscle fatigue, defined as a gradual decline in force-generating capacity, during conventional dynamic (D) leg exercise. To quantitate progression of fatigue, we developed 1) a model featuring integration of maximal voluntary static contraction (MVC...

  1. Restless legs syndrome and periodic leg movements of sleep.

    Science.gov (United States)

    Rye, David B; Trotti, Lynn Marie

    2012-11-01

    Women are more commonly affected than men by restless legs syndrome, and prevalence is highest amongst those of northern European heritage. The motor manifestations include nonvolitional myoclonus (periodic leg movements). Disinhibition of spinal sensorimotor circuits may underlie these primary features and can be affected by peripheral as well as supraspinal networks. Insufficient mobilizable iron stores increase expressivity in some individuals. The sensorimotor features are relieved by dopamine, especially dopamine agonists, gabapentin and its derivatives, and opioids. A diagnosis relies on recognition of key primary and supportive features, and treatments are generally well tolerated, efficacious, and life-changing. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. EFFECTS OF VIEWING DISTANCE AND HEAD FLEXION ON POSTURAL CONTROL DURING ONE AND TWO-LEGGED STANCE

    Directory of Open Access Journals (Sweden)

    Osamu Aoki

    2015-10-01

    Full Text Available Background: Short viewing distances and head flexion decrease and increase postural sway, respectively. Few studies have examined the effects of these factors during one-legged stance or voluntary body leaning within the base of support, both of which often occur in daily life. The purpose of this study was to examine the effect of viewing distance and head flexion in several postural control conditions. Materials and Methods: Fifteen healthy young subjects participated in this study, and center of pressure (CoP displacement was measured in five conditions (gazing 600 cm forward, 150 cm forward, downward, forward with eyes closed, and downward with eyes closed during two- and one-legged stances and voluntary body leaning. Measurements included that the root mean square (RMS of the anteroposterior (A-P and mediolateral (M-L directions during two- and one-legged stance, and maximum A-P and M-L distances during voluntary body leaning. Results: Our results showed that the M-L RMS of 150 cm was less than that of 600 cm during one-legged stance (p = 0.01. Moreover, the A-P and M-L RMS values of downward gazing were lower than those of 600 cm (A-P RMS: p = 0.003 and M-L RMS: p = 0.002. The M-L distances of 150 cm and downward were larger than that of 600 cm (p = 0.002 and p < 0.001, respectively. Conclusions: Our findings suggest that the effect of viewing distance was more evident during one-legged stance and voluntary body leaning.

  3. 75 FR 47504 - Voluntary Education Programs

    Science.gov (United States)

    2010-08-06

    ... America. TTT helps relieve teacher shortages, especially in math, science, special education, and other... of the Secretary 32 CFR Part 68 RIN 0790-AI50 Voluntary Education Programs AGENCY: Office of the... for the operation of voluntary education programs within DoD. Included are: Procedures for Service...

  4. Pedagogical Aspects of Voluntary School Work

    Science.gov (United States)

    Mária Jármai, Erzsébet; Palányi, Ildikó Zsupanekné

    2015-01-01

    The economic importance of voluntary work has been exceedingly appreciated in the last few decades. This is not surprising at all, because it is highly profitable according to the related estimated data. There are 115,9 million people doing voluntary work only in Europe, which means that they would create the world's 7th biggest economy with EUR…

  5. 14 CFR 234.7 - Voluntary reporting.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Voluntary reporting. 234.7 Section 234.7 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS AIRLINE SERVICE QUALITY PERFORMANCE REPORTS § 234.7 Voluntary reporting. (a) In addition to the...

  6. Changing Dynamics in the Voluntary Market (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Heeter, J.

    2014-12-01

    Voluntary green power markets are those in which consumers and institutions voluntarily purchase renewable energy to match their electricity needs. This presentation, presented at the Renewable Energy Markets Conference in December 2014, outlines the voluntary market in 2013, including community choice aggregation and community solar.

  7. 12 CFR 546.4 - Voluntary dissolution.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Voluntary dissolution. 546.4 Section 546.4... ASSOCIATIONS-MERGER, DISSOLUTION, REORGANIZATION, AND CONVERSION § 546.4 Voluntary dissolution. A Federal savings association's board of directors may propose a plan for dissolution of the association. The plan...

  8. Leg ulcers due to hyperhomocysteinemia

    Directory of Open Access Journals (Sweden)

    Krupa Shankar D

    2006-01-01

    Full Text Available Chronic leg ulcers are rare in young adults and generally indicate a vascular cause. We report a case of a 26-year-old man with leg ulcers of eight months duration. Doppler study indicated venous incompetence and a postphlebitic limb. However, as the distribution and number of ulcers was not consistent with stasis alone and no features of collagen vascular disease were noted, a hyperviscosity state was considered and confirmed with significantly elevated homocysteine level in the serum. Administration of vitamins B1, B2, B6 and B12, trimethyl-glycine, mecobalamine, folic acid and povidone iodine dressings with culture-directed antibiotic therapy led to a satisfactory healing of ulcers over a period of one month. Hyperhomocysteinemia must be considered in the differential diagnosis of leg ulcers in young individuals.

  9. Promethus Hot Leg Piping Concept

    Energy Technology Data Exchange (ETDEWEB)

    AM Girbik; PA Dilorenzo

    2006-01-24

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  10. Between voluntary agreement and legislation

    DEFF Research Database (Denmark)

    Gwozdz, Wencke; Hedegaard, Liselotte; Reisch, Lucia

    2009-01-01

    Voluntary agreements and self-imposed standards are broadly applied to restrict the influence food advertising exerts on children’s food choices – yet their effects are unknown. The current project will therefore investigate whether and, if yes, how the Danish Code for Responsible Food Marketing...... Communication towards Children (hereafter: CODE) – with its dependence on a supportive institutional environment and acceptance of as well as dynamics between involved key stakeholders like consumers, political actors and firms – contributes to fighting the obesity pandemic.Thus, we explore within this article...... what information about the process of implementing the CODE as well as about the evolved dynamics between key stakeholders is already available. Here, the recently published report of the PolMark project sheds light on the dynamics between the key stakeholders in relation to the current Danish...

  11. Effect of antagonist muscle fatigue on knee extension torque.

    Science.gov (United States)

    Beltman, J G M; Sargeant, A J; Ball, D; Maganaris, C N; de Haan, A

    2003-09-01

    The effect of hamstring fatigue on knee extension torque was examined at different knee angles for seven male subjects. Before and after a dynamic flexion fatigue protocol (180 degrees s(-1), until dynamic torque had declined by 50%), maximal voluntary contraction extension torque was measured at four knee flexion angles (90 degrees, 70 degrees, 50 degrees and 30 degrees ). Maximal torque generating capacity and voluntary activation of the quadriceps muscle were determined using electrical stimulation. Average rectified EMG of the biceps femoris was determined. Mean dynamic flexion torque declined by 48+/-11%. Extensor maximal voluntary contraction torque, maximal torque generating capacity, voluntary activation and average rectified EMG at the four knee angles were unaffected by the hamstring fatigue protocol. Only at 50 degrees knee angle was voluntary activation significantly lower (15.7%) after fatigue ( P<0.05). In addition, average rectified EMG before fatigue was not significantly influenced by knee angle. It was concluded that a fatigued hamstring muscle did not increase the maximal voluntary contraction extension torque and knee angle did not change coactivation. Three possible mechanisms may explain the results: a potential difference in recruited fibre populations in antagonist activity compared with the fibres which were fatigued in the protocol, a smaller loss in isometric torque generating capacity of the hamstring muscle than was expected from the dynamic measurements and/or a reduction in voluntary activation.

  12. Mutability of bifunctional thigh muscle activity in pedaling due to contralateral leg force generation.

    Science.gov (United States)

    Kautz, S A; Brown, D A; Van der Loos, H F M; Zajac, F E

    2002-09-01

    Locomotion requires uninterrupted transitions between limb extension and flexion. The role of contralateral sensorimotor signals in executing smooth transitions is little understood even though their participation is crucial to bipedal walking. However, elucidating neural interlimb coordinating mechanisms in human walking is difficult because changes to contralateral sensorimotor activity also affect the ipsilateral mechanics. Pedaling, conversely, is ideal for studying bilateral coordination because ipsilateral mechanics can be independently controlled. In pedaling, the anterior and posterior bifunctional thigh muscles develop needed anterior and posterior crank forces, respectively, to dominate the flexion-to-extension and extension-to-flexion transitions. We hypothesized that contralateral sensorimotor activity substantially contributes to the appropriate activation of these bifunctional muscles during the limb transitions. Bilateral pedal forces and surface electromyograms (EMGs) from four thigh muscles were collected from 15 subjects who pedaled with their right leg against a right-crank servomotor, which emulated the mechanical load experienced in conventional two-legged coupled-crank pedaling. In one pedaling session, the contralateral (left) leg pseudo-pedaled (i.e., EMG activity and pedal forces were pedaling-like, but pedal force was not allowed to affect crank rotation). In other sessions, the mechanically decoupled contralateral leg was first relaxed and then produced rhythmic isometric force trajectories during either leg flexion or one of the two limb transitions of the pedaling leg. With contralateral force production in the extension-to-flexion transition (predominantly by the hamstrings), rectus femoris activity and work output increased in the pedaling leg during its flexion-to-extension transition, which occurs simultaneously with contralateral extension-to-flexion in conventional pedaling. Similarly, with contralateral force production in the

  13. Locomotor-like leg movements evoked by rhythmic arm movements in humans.

    Directory of Open Access Journals (Sweden)

    Francesca Sylos-Labini

    Full Text Available Motion of the upper limbs is often coupled to that of the lower limbs in human bipedal locomotion. It is unclear, however, whether the functional coupling between upper and lower limbs is bi-directional, i.e. whether arm movements can affect the lumbosacral locomotor circuitry. Here we tested the effects of voluntary rhythmic arm movements on the lower limbs. Participants lay horizontally on their side with each leg suspended in an unloading exoskeleton. They moved their arms on an overhead treadmill as if they walked on their hands. Hand-walking in the antero-posterior direction resulted in significant locomotor-like movements of the legs in 58% of the participants. We further investigated quantitatively the responses in a subset of the responsive subjects. We found that the electromyographic (EMG activity of proximal leg muscles was modulated over each cycle with a timing similar to that of normal locomotion. The frequency of kinematic and EMG oscillations in the legs typically differed from that of arm oscillations. The effect of hand-walking was direction specific since medio-lateral arm movements did not evoke appreciably leg air-stepping. Using externally imposed trunk movements and biomechanical modelling, we ruled out that the leg movements associated with hand-walking were mainly due to the mechanical transmission of trunk oscillations. EMG activity in hamstring muscles associated with hand-walking often continued when the leg movements were transiently blocked by the experimenter or following the termination of arm movements. The present results reinforce the idea that there exists a functional neural coupling between arm and legs.

  14. Determinants and features of voluntary disclosure in the Chinese stock market

    Directory of Open Access Journals (Sweden)

    Yang Lan

    2013-12-01

    Full Text Available This paper offers in-depth analysis of the determinants and features of voluntary disclosure based on information in the annual reports of 1066 Chinese firms listed on the Shanghai and Shenzhen Stock Exchanges. This extensive sample represents about 80% of all public companies in China. Our findings suggest that voluntary disclosure in China is positively related to firm size, leverage, assets-in-place, and return on equity and is negatively related to auditor type and the level of maturity or sophistication of the intermediary and legal environments. We also find some evidence to suggest a quadratic convex association between state ownership and voluntary disclosure. However, our analysis provides no evidence that extensive disclosure benefits public companies in China in the form of a lower cost of equity.

  15. Determinants and features of voluntary disclosure in the Chinese stock market

    Institute of Scientific and Technical Information of China (English)

    Yang; Lan; Lili; Wang; Xueyong; Zhang

    2013-01-01

    This paper offers in-depth analysis of the determinants and features of voluntary disclosure based on information in the annual reports of 1066 Chinese firms listed on the Shanghai and Shenzhen Stock Exchanges. This extensive sample represents about 80% of all public companies in China. Our findings suggest that voluntary disclosure in China is positively related to firm size,leverage, assets-in-place, and return on equity and is negatively related to auditor type and the level of maturity or sophistication of the intermediary and legal environments. We also find some evidence to suggest a quadratic convex association between state ownership and voluntary disclosure. However, our analysis provides no evidence that extensive disclosure benefits public companies in China in the form of a lower cost of equity.

  16. Altering spinal cord excitability enables voluntary movements after chronic complete paralysis in humans.

    Science.gov (United States)

    Angeli, Claudia A; Edgerton, V Reggie; Gerasimenko, Yury P; Harkema, Susan J

    2014-05-01

    Previously, we reported that one individual who had a motor complete, but sensory incomplete spinal cord injury regained voluntary movement after 7 months of epidural stimulation and stand training. We presumed that the residual sensory pathways were critical in this recovery. However, we now report in three more individuals voluntary movement occurred with epidural stimulation immediately after implant even in two who were diagnosed with a motor and sensory complete lesion. We demonstrate that neuromodulating the spinal circuitry with epidural stimulation, enables completely paralysed individuals to process conceptual, auditory and visual input to regain relatively fine voluntary control of paralysed muscles. We show that neuromodulation of the sub-threshold motor state of excitability of the lumbosacral spinal networks was the key to recovery of intentional movement in four of four individuals diagnosed as having complete paralysis of the legs. We have uncovered a fundamentally new intervention strategy that can dramatically affect recovery of voluntary movement in individuals with complete paralysis even years after injury.

  17. MYOELECTRIC ALTERATIONS AFTER VOLUNTARY INDUCED HIGH - AND LOW - FREQUENCY FATIGUE

    Directory of Open Access Journals (Sweden)

    Vojko Strojnik

    2008-06-01

    Full Text Available The aim of the study was to find whether voluntary induced high- and low-frequency peripheral fatigue exhibit specific alteration in surface EMG signal (SEMG during evoked and maximum voluntary contractions. Ten male students of physical education performed 60 s long stretch-shortening cycle (SSC exercise with maximal intensity and 30 s long concentric (CON exercise with maximal intensity. To verify voluntary induced peripheral fatigue, knee torques during low- (T20 and high-frequency electrical stimulation (T100 of relaxed vastus lateralis muscle (VL were obtained. Contractile properties of the VL were measured with passive twitch and maximal voluntary knee extension test (MVC. Changes in M-waves and SEMG during MVC test were used to evaluate the differences in myoelectrical signals. T100/T20 ratio decreased by 10.9 ± 8.4 % (p < 0.01 after the SSC exercise and increased by 35.9 ± 17.5 % (p < 0.001 after the CON exercise. Significant SEMG changes were observed only after the CON exercise where peak to peak time of the M-waves increased by 9.2 ± 13.3 % (p < 0.06, SEMG amplitude during MVC increased by 32.9 ± 21.6 % (p < 0.001 and SEMG power spectrum median frequency decreased by 11.0 ± 10.5 % (p < 0.05. It is concluded that high frequency fatigue wasn't reflected in SEMG, however the SEMG changes after the CON seemed to reflect metabolic changes due to acidosis

  18. FAQs on leg ulcer care.

    Science.gov (United States)

    Anderson, Irene; King, Brenda; Knight, Susan; Keynes, Milton

    In a webchat on leg ulcer management issues, hosted by Nursing Times, participants raised three key areas of care: the role of healthcare assistants in compression bandaging; reporting and investigating damage caused by compression therapy; and recommendations for dressings to be used under compression. This article discusses each of these in turn.

  19. Physiological alterations of maximal voluntary quadriceps activation by changes of knee joint angle.

    Science.gov (United States)

    Becker, R; Awiszus, F

    2001-05-01

    The purpose of this study was to investigate the influence of different angles of the knee joint on voluntary activation of the quadriceps muscle, estimating the ability of a subject to activate a muscle maximally by means of voluntary contraction. Isometric torque measurement was performed on 6 healthy subjects in 5 degrees intervals between 30 degrees and 90 degrees of knee joint flexion. Superimposed twitches at maximal voluntary contraction (MVC) and at a level of 60% and 40% of the MVC were applied and the voluntary activation estimated. At between 30 degrees and 75 degrees of knee flexion, the maximal extension torque increased at an average rate of 2.67 +/- 0.6 Nm/degree, followed by a decline with further flexion. However, throughout the joint-angle range tested, voluntary activation increased on average by 0.37%/degree with a maximum at 90 degrees of flexion. Due to the influence of joint position it is not possible to generalize results obtained at the knee joint angle of 90 degrees of flexion, which is usually used for the quadriceps twitch-interpolation technique. Consequently, it is useful to investigate voluntary activation deficits in knee joint disorders at a range of knee joint angles that includes, in particular, the more extended joint angles used frequently during daily activity.

  20. Restless Legs Syndrome -- Causes and Symptoms

    Science.gov (United States)

    ... Overview & Facts Causes & Symptoms Self-Tests & Diagnosis Treatment Restless Legs Syndrome - Causes & Symptoms Causes What causes of restless legs syndrome varies from person to person. In some cases ...

  1. AN ECONOMETRIC APPROACH ABOUT VOLUNTARY TURNOVER

    Directory of Open Access Journals (Sweden)

    ADALET EREN

    2013-06-01

    Full Text Available This study analyzes individual and organizational variables that affect voluntary turnover are determined in the special defence and security companies. A binomial logistic regression model is used to estimate voluntary turnover.  Binomial Logistic regression, reliability test (scale alfa, variance (ANOVA, Post-hoc/Tukey, correlation (Pearson and other basic statistical techniques  with SPSS 13 statistical packet program was used in the analyzes ofresearch data. The study finds that; situation of suppose working, number of child, number of death child, number of home’s moving, support of rent, total monthly income of household, last work’s region, number of prizes, affect voluntary turnover are determined.

  2. Bed rest attenuates sympathetic and pressor responses to isometric exercise in antigravity leg muscles in humans.

    Science.gov (United States)

    Kamiya, Atsunori; Michikami, Daisaku; Shiozawa, Tomoki; Iwase, Satoshi; Hayano, Junichiro; Kawada, Toru; Sunagawa, Kenji; Mano, Tadaaki

    2004-05-01

    Although spaceflight and bed rest are known to cause muscular atrophy in the antigravity muscles of the legs, the changes in sympathetic and cardiovascular responses to exercises using the atrophied muscles remain unknown. We hypothesized that bed rest would augment sympathetic responses to isometric exercise using antigravity leg muscles in humans. Ten healthy male volunteers were subjected to 14-day 6 degrees head-down bed rest. Before and after bed rest, they performed isometric exercises using leg (plantar flexion) and forearm (handgrip) muscles, followed by 2-min postexercise muscle ischemia (PEMI) that continues to stimulate the muscle metaboreflex. These exercises were sustained to fatigue. We measured muscle sympathetic nerve activity (MSNA) in the contralateral resting leg by microneurography. In both pre- and post-bed-rest exercise tests, exercise intensities were set at 30 and 70% of the maximum voluntary force measured before bed rest. Bed rest attenuated the increase in MSNA in response to fatiguing plantar flexion by approximately 70% at both exercise intensities (both P antigravity leg muscles.

  3. A leg-local neural mechanism mediates the decision to search in stick insects.

    Science.gov (United States)

    Berg, Eva M; Hooper, Scott L; Schmidt, Joachim; Büschges, Ansgar

    2015-08-01

    In many animals, individual legs can either function independently, as in behaviors such as scratching or searching, or be used in coordinated patterns with other legs, as in walking or climbing. While the control of walking has been extensively investigated, the mechanisms mediating the behavioral choice to activate individual legs independently are poorly understood. We examined this issue in stick insects, in which each leg can independently produce a rhythmic searching motor pattern if it doesn't find a foothold [1-4]. We show here that one non-spiking interneuron, I4, controls searching behavior in individual legs. One I4 is present in each hemi-segment of the three thoracic ganglia [5, 6]. Search-inducing sensory input depolarizes I4. I4 activity was necessary and sufficient to initiate and maintain searching movements. When substrate contact was provided, I4 depolarization no longer induced searching. I4 therefore both integrates search-inducing sensory input and is gated out by other sensory input (substrate contact). Searching thus occurs only when it is behaviorally appropriate. I4 depolarization never elicited stepping. These data show that individual, locally activated neurons can mediate the behavioral choice to use individual legs independently. This mechanism may be particularly important in insects' front legs, which can function independently like vertebrate arms and hands [7]. Similar local command mechanisms that selectively activate the pattern generators controlling repeated functional units such as legs or body segments may be present in other systems.

  4. Contribution of non-extensor muscles of the leg to maximal-effort countermovement jumping

    OpenAIRE

    Yoshioka Shinsuke; Komura Taku; Nagano Akinori; Fukashiro Senshi

    2005-01-01

    Abstract Background The purpose of this study was to determine the effects of non-extensor muscles of the leg (i.e., muscles whose primary function is not leg extension) on the kinematics and kinetics of human maximal-effort countermovement jumping. Although it is difficult to address this type of question through experimental procedures, the methodology of computer simulation can be a powerful tool. Methods A skeletal model that has nine rigid body segments and twenty degrees of freedom was ...

  5. [Restless legs syndrome and nocturnal leg pain : Differential diagnosis and treatment].

    Science.gov (United States)

    Hornyak, M; Stiasny-Kolster, K; Evers, S; Happe, S

    2011-09-01

    Pain in the legs belongs to the five most frequent regional pain symptoms. Restless legs syndrome (RLS) presents a particular differential diagnosis for pain in the legs, which is characterized by a nocturnal urge to move the legs often associated with painful sensations in the legs. It is one of the most common neurological disorders and probably the leading cause of nocturnal pain in the legs. In this overview, the diagnosis and therapy of RLS as well as aspects of pain therapy of the disorder are presented. In addition, the differential diagnoses for exclusion of other specific causes of nocturnal pain in the legs are discussed.

  6. Neuronal correlates of voluntary facial movements.

    Science.gov (United States)

    Krippl, Martin; Karim, Ahmed A; Brechmann, André

    2015-01-01

    Whereas the somatotopy of finger movements has been extensively studied with neuroimaging, the neural foundations of facial movements remain elusive. Therefore, we systematically studied the neuronal correlates of voluntary facial movements using the Facial Action Coding System (FACS, Ekman et al., 2002). The facial movements performed in the MRI scanner were defined as Action Units (AUs) and were controlled by a certified FACS coder. The main goal of the study was to investigate the detailed somatotopy of the facial primary motor area (facial M1). Eighteen participants were asked to produce the following four facial movements in the fMRI scanner: AU1+2 (brow raiser), AU4 (brow lowerer), AU12 (lip corner puller) and AU24 (lip presser), each in alternation with a resting phase. Our facial movement task induced generally high activation in brain motor areas (e.g., M1, premotor cortex, supplementary motor area, putamen), as well as in the thalamus, insula, and visual cortex. BOLD activations revealed overlapping representations for the four facial movements. However, within the activated facial M1 areas, we could find distinct peak activities in the left and right hemisphere supporting a rough somatotopic upper to lower face organization within the right facial M1 area, and a somatotopic organization within the right M1 upper face part. In both hemispheres, the order was an inverse somatotopy within the lower face representations. In contrast to the right hemisphere, in the left hemisphere the representation of AU4 was more lateral and anterior compared to the rest of the facial movements. Our findings support the notion of a partial somatotopic order within the M1 face area confirming the "like attracts like" principle (Donoghue et al., 1992). AUs which are often used together or are similar are located close to each other in the motor cortex.

  7. Neuronal correlates of voluntary facial movements

    Directory of Open Access Journals (Sweden)

    Martin eKrippl

    2015-10-01

    Full Text Available Whereas the somatotopy of finger movements has been extensively studied with neuroimaging, the neural foundations of facial movements remain elusive. Therefore, we systematically studied the neuronal correlates of voluntary facial movements using the Facial Action Coding System (FACS,Ekman et al., 2002. The facial movements performed in the MRI scanner were defined as Action Units (AUs and were controlled by a certified FACS coder. The main goal of the study was to investigate the detailed somatotopy of the facial primary motor area (facial M1. Eighteen participants were asked to produce the following four facial movements in the fMRI scanner: AU1+2 (brow raiser, AU4 (brow lowerer, AU12 (lip corner puller and AU24 (lip presser, each in alternation with a resting phase.Our facial movement task induced generally high activation in brain motor areas (e.g. M1, premotor cortex, SMA, putamen, as well as in the thalamus, insula and visual cortex. BOLD activations revealed overlapping representations for the four facial movements. However, within the activated facial M1 areas, we could find distinct peak activities in the left and right hemisphere supporting a rough somatotopic upper to lower face organization within the right facial M1 area, and a somatotopic organization within the right M1 upper face part. In both hemispheres, the order was an inverse somatotopy within the lower face representations. In contrast to the right hemisphere, in the left hemisphere the representation of AU 4 was more lateral and anterior compared to the rest of the facial movements. Our findings support the notion of a partial somatotopic order within the M1 face area confirming the like attracts like principle (Donoghue et al., 1992 . AUs which are often used together or are similar are located close to each other in the motor cortex.

  8. Anticipatory signatures of voluntary memory suppression.

    Science.gov (United States)

    Hanslmayr, Simon; Leipold, Philipp; Pastötter, Bernhard; Bäuml, Karl-Heinz

    2009-03-04

    Voluntary memory suppression can keep unwanted memories from entering consciousness, inducing later forgetting of the information. In the present study, we searched for the existence of anticipatory processes, mediating such voluntary memory suppression. Using the think/no-think paradigm, subjects received a cue whether to prepare to think of a previously studied cue-target pair or whether to not let a previously studied cue-target pair enter consciousness. Examining event-related potentials, we identified two electrophysiological processes of voluntary memory suppression: (1) an early anticipatory process operating before the memory cue for a to-be-suppressed memory was provided, and (2) a later process operating after memory cue presentation. Both ERP effects were due to a decreased right frontal and left parietal positivity. They were positively related and predicted later forgetting. The results point to the existence of anticipatory processes, mediating voluntary memory suppression.

  9. Pedagogical Aspects of Voluntary School Work

    Directory of Open Access Journals (Sweden)

    Mária Jármai Erzsébet

    2015-03-01

    Full Text Available The economic importance of voluntary work has been exceedingly appreciated in the last few decades. This is not surprising at all, because it is highly profitable according to the related estimated data. There are 115,9 million people doing voluntary work only in Europe, which means that they would create the world's 7th biggest economy with EUR 282 billion value creation if they formed an individual state. The organizations know that voluntary work has several advantages apart from the economic benefits. It is profitable both for the society and for the individuals as well. Several researches have proven that voluntary work positively influences the development of the personality, because the key-competencies - such as: co-operation, empathy, solidarity, conflict handling, problem solving, etc. - expected in the labor market can be improved.

  10. Managing voluntary turnover through challenging assignments

    NARCIS (Netherlands)

    Preenen, P.T.Y.; Pater, I.E. de; Vianen, A.E.M. van; Keijzer, L.

    2011-01-01

    This study examines employees' challenging assignments as manageable means to reduce turnover intentions, job search behaviors, and voluntary turnover. Results indicate that challenging assignments are negatively related to turnover intentions and job search behaviors and that these relationships

  11. Corticospinal excitability in human voluntary movement

    NARCIS (Netherlands)

    Elswijk, G.A.F. van

    2008-01-01

    The research described in this thesis addressed the neurophysiologic changes in the human corticospinal system during preparation and execution of voluntary hand movements. The experiments involved transcranial magnetic stimulation (TMS) of the motor cortex combined with electromyography (EMG) and e

  12. Contemplated Suicide Among Voluntary and Involuntary Retirees

    Science.gov (United States)

    Peretti, Peter O.; Wilson, Cedric

    1978-01-01

    This study explored anomic and egoistic dimensions of contemplated suicide among voluntary and involuntary retired males. Results indicated a direct relationship between anomie and egoism on the one hand, and contemplation of suicide on the other. (Author)

  13. A Free Market Requires Voluntary Actions

    DEFF Research Database (Denmark)

    Sløk-Madsen, Stefan Kirkegaard

    are essential to the construct of consumer sovereignty. Understanding the degree of voluntary actions in a given commercial setting has implications for both business strategy and policy making. This paper thus aims to contribute to explain why restricted markets become crony capitalism.......This paper draws attention to the importance of the understanding of voluntary actions in the free market construct. Failing to understand the role of voluntary actions in the free market construct will often result in discussions of capitalism versus socialism focusing on asset ownership...... and not consumer sovereignty. I argue that asset ownership is less important than true consumer sovereignty, which again is the essential argument for why capitalism is the superior mode of resource allocation and social organization. The paper analyzes how our understanding of markets and voluntary actions...

  14. Contemplated Suicide Among Voluntary and Involuntary Retirees

    Science.gov (United States)

    Peretti, Peter O.; Wilson, Cedric

    1978-01-01

    This study explored anomic and egoistic dimensions of contemplated suicide among voluntary and involuntary retired males. Results indicated a direct relationship between anomie and egoism on the one hand, and contemplation of suicide on the other. (Author)

  15. Changes in voluntary quadriceps activation predict changes in muscle strength and gait biomechanics following knee joint effusion.

    Science.gov (United States)

    Pietrosimone, Brian; Lepley, Adam S; Murray, Amanda M; Thomas, Abbey C; Bahhur, Nael O; Schwartz, Todd A

    2014-09-01

    It has been hypothesized that arthrogenic muscle inhibition is responsible for altering physical function following knee injury. The association between the onset of arthrogenic muscle inhibition, measured using voluntary quadriceps activation, and changes in muscle strength and gait biomechanics are unknown. Outcomes were collected before and following a 60 ml experimental knee effusion in eighteen healthy participants. Voluntary quadriceps activation was the predictor variable, while the criterion variable included, maximal voluntary isometric strength, peak knee flexion angle, peak internal knee extension moment, and peak vertical ground reaction forces during the first half of stance phase upon stair descent. Percent change scores (Δ) were imputed into linear regression equations to determine associations between predictor and criterion variables. The variance in Δ voluntary quadriceps activation significantly predicted 87% the variance in the Δ strength (R(2)=0.87, Pknee flexion angle, Δ voluntary quadriceps activation predicted an additional 29% (Δ R(2)=0.29, P=0.007) of the variance in the Δ knee extension moment (R(2)=0.54, P=0.003, Δ knee extension moment=-10.79+0.74Δ knee flexion angle+1.64Δ voluntary quadriceps activation) following knee effusion. Immediate quadriceps activation deficits following joint effusion result in immediate alterations in muscle strength, knee extensor moment and vertical ground reaction force during gait. Published by Elsevier Ltd.

  16. Pull factors of Finland and voluntary work

    OpenAIRE

    Jurvakainen, Janika

    2016-01-01

    This thesis studies pull factors of Finland and voluntary work. The aim of this study is to understand the pull factors of Finland from the perspective of young travelers. Which pull factors attract to choose Finland as their destination? In addition, which pull factors attract young travelers to participate in international voluntary work? The commissioner of this thesis is Allianssi Youth Exchange. The thesis is research-based and includes a quantitative Webropol survey and some qualit...

  17. Chronic Knee Injuries Impair the Voluntary Activation of Quadriceps Femoris%陈旧性膝关节运动损伤者股四头肌随意动员能力下降

    Institute of Scientific and Technical Information of China (English)

    徐刚; 黄力平; 周石; 王昭君; 李猛; 敖铭; 王聪; 赵美苓; 梁军

    2012-01-01

    目的:观察陈旧性膝关节运动损伤股四头肌随意动员能力的变化.方法:60名天津体育学院学生,自愿参加测试,根据其是否有陈旧性膝关节运动损伤分为2组,损伤组(有训练史)30人,对照组(无训练史)30人.应用股四头肌随意动员能力评定系统测定分析股四头肌最大随意等长肌力(MVC)、随意动员能力(MA)和力量上升速率(RFD).结果:对照组两侧股四头肌MVC、MA和RFD无显著差异(P>0.05),损伤组两侧股四头肌MVC无显著性差异(P>0.05).对照组右侧股四头肌MVC、RFD值显著低于损伤组未损伤侧(P<0.05,P< 0.01),损伤组膝关节损伤侧MA、RFD值显著低于未损伤侧(P< 0.05,P< 0.01).结论:即使陈旧性膝关节运动损伤者股四头肌肌肉力量已恢复到未损伤侧水平,其随意动员能力和力量上升速率依然较低,膝关节神经肌肉控制仍较差,这可能是影响陈旧性膝关节运动损伤功能状态的主要因素之一.股四头肌随意动员能力评价系统可检测这一变化.%Objective To determine whether voluntary activation of quadriceps femoris persons with chronic knee injuries is impaired. Methods Thirty participants with knee injuries and thirty healthy participants voluntarily participated in the study. Muscle strength in maximum voluntary contraction (MVC) .muscle activation (MA),and the rate of force development (RFD) in isometric knee extension were assessed for both legs using a custom-built dynamometer. Independent-Samples T test was used to compare the mean values between the two groups or/and both legs. Results No significant differences were found in the measured variables between the two legs in the healthy control group. There was no significant difference in the MVC between legs in the injury group(P>0.05). The MVC and RFD of the right leg in the control group were lower than the uninjured left side in the injury group (P<0.05,P< 0.01). The MA and RFD of the injured side in

  18. Restless legs syndrome in multiple system atrophy.

    Science.gov (United States)

    Ghorayeb, Imad; Dupouy, Sandrine; Tison, François; Meissner, Wassilios G

    2014-12-01

    The purpose of the study was to evaluate the frequency of restless legs syndrome in 30 patients with multiple system atrophy. Eight patients complained from restless legs syndrome, their severity score was 19.4 ± 4.1. Pittsburgh Sleep Quality Index scores were significantly higher in patients with restless legs syndrome than those without (9.3 ± 3.7 vs. 4.8 ± 2.9, p = 0.00165). Periodic limb movements were found in 75% of patients with restless legs syndrome. Restless legs syndrome is more prevalent in multiple system atrophy as compared to the acknowledged prevalence in the general population.

  19. Elastic actuation for legged locomotion

    Science.gov (United States)

    Cao, Chongjing; Conn, Andrew

    2017-04-01

    The inherent elasticity of dielectric elastomer actuators (DEAs) gives this technology great potential in energy efficient locomotion applications. In this work, a modular double cone DEA is developed with reduced manufacturing and maintenance time costs. This actuator can lift 45 g of mass (5 times its own weight) while producing a stroke of 10.4 mm (23.6% its height). The contribution of the elastic energy stored in antagonistic DEA membranes to the mechanical work output is experimentally investigated by adding delay into the DEA driving voltage. Increasing the delay time in actuation voltage and hence reducing the duty cycle is found to increase the amount of elastic energy being recovered but an upper limit is also noticed. The DEA is then applied to a three-segment leg that is able to move up and down by 17.9 mm (9% its initial height), which demonstrates the feasibility of utilizing this DEA design in legged locomotion.

  20. 47 CFR 80.310 - Watch required by voluntary vessels.

    Science.gov (United States)

    2010-10-01

    ... Watches § 80.310 Watch required by voluntary vessels. Voluntary vessels not equipped with DSC must.... Voluntary vessels equipped with VHF-DSC equipment must maintain a watch on 2182 kHz and on either 156.525... used to communicate. Voluntary vessels equipped with MF-HF DSC equipment must have the radio turned...

  1. Win-stay-lose-learn promotes cooperation in the prisoner's dilemma game with voluntary participation.

    Science.gov (United States)

    Chu, Chen; Liu, Jinzhuo; Shen, Chen; Jin, Jiahua; Shi, Lei

    2017-01-01

    Voluntary participation, demonstrated to be a simple yet effective mechanism to promote persistent cooperative behavior, has been extensively studied. It has also been verified that the aspiration-based win-stay-lose-learn strategy updating rule promotes the evolution of cooperation. Inspired by this well-known fact, we combine the Win-Stay-Lose-Learn updating rule with voluntary participation: Players maintain their strategies when they are satisfied, or players attempt to imitate the strategy of one randomly chosen neighbor. We find that this mechanism maintains persistent cooperative behavior, even further promotes the evolution of cooperation under certain conditions.

  2. Avoiding a fate worse than death: an argument for legalising voluntary physician-based euthanasia.

    Science.gov (United States)

    Werren, Julia; Yuksel, Necef; Smith, Saxon

    2012-09-01

    The legalisation of voluntary physician-based euthanasia is currently the subject of much political, social and ethical debate and there is evidence in Australia of growing support for its implementation. In addressing many of the issues that surround legalisation, the article looks at some overseas jurisdictions that have legalised euthanasia to determine whether the social, political and ethical concerns prominent in the Australian debate have proved problematic in other jurisdictions. In addition, the article examines the report on the Dying with Dignity Bill 2009 (Tas) which commented extensively on the issues relating to voluntary physician-based euthanasia.

  3. RAPID KNEE-EXTENSIONS TO INCREASE QUADRICEPS MUSCLE ACTIVITY IN PATIENTS WITH TOTAL KNEE ARTHROPLASTY: A RANDOMIZED CROSS-OVER STUDY

    Science.gov (United States)

    Wilquin, Lousia; Jakobsen, Thomas Linding; Holsgaard-Larsen, Anders; Bandholm, Thomas

    2017-01-01

    Background Inhibition of the quadriceps muscle and reduced knee-extension strength is common shortly following total knee arthroplasty (weeks to months), due to reduced voluntary activation of the quadriceps muscle. In healthy subjects, strength training with heavy loads is known to increase agonist muscle activity, especially if the exercise is conducted using rapid muscle contractions. Purpose The purpose of this study was to examine if patients with total knee arthroplasty could perform rapid knee-extensions using a 10 RM load four to eight weeks after surgery, and the degree to which rapid knee-extensions were associated with greater voluntary quadriceps muscle activity during an experimental strength training session, compared to that elicited using slow knee-extensions. Study Design A randomized cross-over study. Methods Twenty-four patients (age 66.5) 4-8 weeks post total knee arthroplasty randomly performed one set of five rapid, and one set of five slow knee-extensions with the operated leg, using a load of their 10 repetition maximum, while surface electromyography recordings were obtained from the vastus medialis and lateralis of the quadriceps muscle. Results Data from 23 of the 24 included patients were analyzed. Muscle activity was significantly higher during rapid knee-extensions (120.2% [10th-90th percentile: 98.3-149.1]) compared to slow knee-extensions (106.0% [88.8-140.8]) for the vastus lateralis (pknee-extensions were performed at a median angular velocity of 19.7 degrees/sec (13.7-24.4) and 51.4 degrees/sec (28.9-63.1), respectively Conclusion Four to eight weeks after their total knee arthroplasty, the patients in the present study were able to conduct rapid knee-extensions according to the experimental protocol with an approximately doubled angular velocity compared to slow knee-extensions. This was associated with increased muscle activity in the vastus lateralis when compared to slow knee-extensions, but not in the vastus medialis. Whether

  4. Pediatric restless legs syndrome diagnostic criteria: an update by the International Restless Legs Syndrome Study Group.

    Science.gov (United States)

    Picchietti, Daniel L; Bruni, Oliviero; de Weerd, Al; Durmer, Jeffrey S; Kotagal, Suresh; Owens, Judith A; Simakajornboon, Narong

    2013-12-01

    Specific diagnostic criteria for pediatric restless legs syndrome (RLS) were published in 2003 following a workshop at the National Institutes of Health. Due to substantial new research and revision of the adult RLS diagnostic criteria, a task force was chosen by the International Restless Legs Syndrome Study Group (IRLSSG) to consider updates to the pediatric diagnostic criteria. A committee of seven pediatric RLS experts developed a set of 15 consensus questions to review, conducted a comprehensive literature search, and extensively discussed potential revisions. The committee recommendations were approved by the IRLSSG executive committee and reviewed by the IRLSSG membership. The pediatric RLS diagnostic criteria were simplified and integrated with the newly revised adult RLS criteria. Specific recommendations were developed for pediatric application of the criteria, including consideration of typical words used by children to describe their symptoms. Pediatric aspects of differential diagnosis, comorbidity, and clinical significance were then defined. In addition, the research criteria for probable and possible pediatric RLS were updated and criteria for a related condition, periodic limb movement disorder (PLMD), were clarified. Revised diagnostic criteria for pediatric RLS have been developed, which are intended to improve clinical practice and promote further research. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  5. 设计师访谈:Three Legged Legs

    Institute of Scientific and Technical Information of China (English)

    JOE; RUSS

    2007-01-01

    Greg Gunn、Casey Hunt和Reza Rasoli,又称Three Legged Legs。于2006年获得了全球学生动画奖(Global Student Animation Award)。现在他们又带回了一个精彩的新短片《Samurai》。我们自然也不会放过这次机会,看看能不能了解到更多内幕信息。

  6. [When to worry about before a vascular chronic leg ulcer?].

    Science.gov (United States)

    Lazareth, I

    2016-09-01

    Leg ulcers are a chronic condition. Healing can be long for venous ulcers and the risk of complications is significant. Infection is the most severe complication and can occur in the form of easily diagnosed acute bacterial dermohypodermitis that generally responds well to antibiotic treatment if given at an appropriate dose or in the form of localized infection that is more difficult to diagnosis. Indeed, no consensus has been reached in the literature on the clinical criteria to retain for the diagnosis of localized infection. Similarly, the most appropriate treatment remains to be established. Local care would be a logical starting point, followed by systemic antibiotics if this approach is unsuccessful. Individual conditions also should be taken into consideration (immunodepression, severe arteriopathy warranting more rapid use of systemic antibiotics). The second most frequent complication is an allergic reaction to a topical agent used for wound care. The rate of sensitivization in patients with leg ulcers is high (60 %), although the rate is declining with modern dressings. No product can be considered perfectly safe for these polysensitized patients. Dermocorticoid therapy can be very effective. Allergology tests are needed. Certain leg ulcers require special care from diagnosis. An arterial origin must be suspected for deep, or necrotic ulcers. Arterial supply must be explored rapidly, followed by a revascularization procedure when necessary. Highly painful superficial extensive necrotic ulcers due to necrotic angiodermitis require hospital care for skin grafts that will control the antiodermitis and provide pain. Carcinoma should be suspected in cases of leg ulcers with an atypical localization exhibiting excessive budding. A biopsy is mandatory for leg ulcers with an unusual course (absence of healing despite well-conducted care).

  7. [Pain in venous thrombosis of the leg].

    Science.gov (United States)

    Henriet, J P

    1992-01-01

    According to D. Reinharez, pain and edema are the commonest presenting symptoms in phlebology. Pain is one of the most classical symptoms of an ordinary deep venous thrombosis, a valuable feature when present, in the form of deep tension, heaviness, swelling and a feeling of dead weight. It is often absent or slight. It may consist merely of a dull cramp, or of an "undefinable" (C. Bourde) odd, heavy leg. It generally affects the calf but may involve the sole of the foot, the heel, the thigh, the groin or even the true pelvis. This feeling, although "imprecise and variable" (P. Wallois, P. Griton) is highly suggestive. It increases on standing and walking in the form of unilateral uncomfortable tension, heaviness or painful swelling, which maybe a source of worry or even anxiety to the patient. Tenderness on palpation of venous tracts and their stretching is more suggestive. In the opinion of M. Duruble, Neuhof's sign (feeling of tender fullness of the calf) is more reliable than Homans' sign (pain in the calf caused by passive dorsiflexion of the foot, with the lower limb in extension) which essentially stretches only the posterior tibial venous system. The value of Sigg's sign (pain in the popliteal fossa on passive extension of the knee) is controversial. Far more rare is phlegmasia coerulea dolens or Grégoire's blue leg, complicating phlegmasia alba dolens or of sudden onset, with initial very severe or even "intolerable" pain (J.J. Pinot) in Scarpa's triangle, rapidly spreading to the limb. In varicose phlebitis (M. Perrin) or superficial thrombophlebitis or varico-phlebitis (A.A. Ramelet) or superficial venitis (J.P. Henriet), pain most often consists of moderate burning tension overlying the thrombosed vein(s), increased by palpation and mobilisation. Sometimes severe initially, it is exacerbated by the slightest touch. In total, pain, regardless of its characteristics, its site and/or its severity, is one of the most constant clinical features of venous

  8. Wing and body motion and aerodynamic and leg forces during take-off in droneflies

    OpenAIRE

    Chen, Mao Wei; Zhang, Yan Lai; Sun, Mao

    2013-01-01

    Here, we present a detailed analysis of the take-off mechanics in droneflies performing voluntary take-offs. Wing and body kinematics of the insects during take-off were measured using high-speed video techniques. Based on the measured data, the inertia force acting on the insect was computed and the aerodynamic force of the wings was calculated by the method of computational fluid dynamics. Subtracting the aerodynamic force and the weight from the inertia force gave the leg force. In take-of...

  9. Epilepsy and restless legs syndrome.

    Science.gov (United States)

    Geyer, James D; Geyer, Emery E; Fetterman, Zachary; Carney, Paul R

    2017-03-01

    Restless legs syndrome (RLS) is a common neurological movement disorder occurring in approximately 10% of the general population. The prevalence of moderately severe RLS is 2.7% overall (3.7% for women and 1.7% for men). Epilepsy is also a common neurological disorder with significant associated morbidity and impact on quality of life. We evaluated the severity and frequency of primary RLS in patients with localization-related temporal lobe epilepsy (TLE) and investigated the role of prodromal RLS symptoms as a warning sign and lateralizing indicator. All epilepsy patients seen in the outpatient clinic were screened for movement disorders from 2005 to 2015. Ninety-eight consecutive patients with localization-related TLE (50 right TLE and 48 left TLE) who met inclusion criteria were seen in the outpatient clinic. The control group consisted of 50 individuals with no history or immediate family history of epilepsy. Each patient was evaluated with the International Restless Legs Study Group (IRLSSG) questionnaire, NIH RLS diagnostic criteria, ferritin level, and comprehensive sleep screening including polysomnography. Furthermore, patients with obstructive sleep apnea or a definite cause of secondary restless legs syndrome such as low serum ferritin or serum iron levels were also excluded from the study. There was a significant association between the type of epilepsy and whether or not patients had RLS χ(2) (1)=10.17, prestlessness was typically described as moderately severe. The RLS symptoms were more common and somewhat more severe in the right TLE group than the left TLE group. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. [Epidemiology of restless legs syndrome].

    Science.gov (United States)

    Ghorayeb, I; Tison, F

    2009-01-01

    Restless legs syndrome (RLS) is a chronic sensorimotor disorder where patients complain of an almost irresistible urge to move their legs. This urge can often be accompanied by pain or other unpleasant sensations, it either occurs or worsens with rest particularly at night, and improves with activity. The International Restless Legs Syndrome Study Group has established four essential criteria for clinical diagnosis of RLS. Affecting an estimated 7.2 to 11.5% of the adult population, the symptoms of RLS may be associated with significant sleep disturbance and may have a negative impact on quality of life. The prevalence of RLS increases with age, and women are more frequently affected than men. In France, the estimated prevalence is 8.5%. Among sufferers, 4.4% complain of very severe symptoms. Although RLS is mainly idiopathic, several clinical conditions have been associated with it, especially iron deficiency with or without anemia, end-stage renal disease and pregnancy. These conditions may share a common pathophysiological mechanism involving a disorder of iron metabolism. By contrast, controversy persists as to whether polyneuropathy, particularly when associated with diabetes, is to be considered as an important cause of secondary RLS. This association is difficult to demonstrate as conventional electromyography is not adequate to detect small fiber neuropathy often associated with diabetes. RLS is often underdiagnosed and few subjects receive recommended RLS drug treatment. There is a clear need for complementary education to improve the accurate diagnosis of RLS. Indeed, better knowledge of this syndrome is a prerequisite to prompt an appropriate therapeutic management.

  11. Neuroimaging in Restless Legs Syndrome.

    Science.gov (United States)

    Provini, Federica; Chiaro, Giacomo

    2015-09-01

    Neuroimaging studies are of crucial relevance in defining the pathophysiology of restless legs syndrome (RLS). MRI studies showed no structural brain lesions and confirmed a central iron deficiency. Structural and functional studies showed an involvement of the thalamus, sensorimotor cortical areas, and cerebellum in RLS and assessed neurotransmission abnormalities in the dopaminergic and opiate systems. Finally, glutamatergic hyperactivity has been proposed as a cause of disrupted and shortened sleep in RLS. Differences among the results of the studies make it difficult to draw any definitive conclusions, thus, suggesting the need for future research.

  12. Common mechanics of mode switching in locomotion of limbless and legged animals.

    Science.gov (United States)

    Kuroda, Shigeru; Kunita, Itsuki; Tanaka, Yoshimi; Ishiguro, Akio; Kobayashi, Ryo; Nakagaki, Toshiyuki

    2014-06-06

    Crawling using muscular waves is observed in many species, including planaria, leeches, nemertea, aplysia, snails, chitons, earthworms and maggots. Contraction or extension waves propagate along the antero-posterior axis of the body as the crawler pushes the ground substratum backward. However, the observation that locomotory waves can be directed forward or backward has attracted much attention over the past hundred years. Legged organisms such as centipedes and millipedes exhibit parallel phenomena; leg tips form density waves that propagate backward or forward. Mechanical considerations reveal that leg-density waves play a similar role to locomotory waves in limbless species, and that locomotory waves are used by a mechanism common to both legged and limbless species to achieve crawling. Here, we report that both mode switching of the wave direction and friction control were achieved when backward motion was induced in the laboratory. We show that the many variations of switching in different animals can essentially be classified in two types according to mechanical considerations. We propose that during their evolution, limbless crawlers first moved in a manner similar to walking before legs were obtained. Therefore, legged crawlers might have learned the mechanical mode of movement involved in walking long before obtaining legs.

  13. From Voluntary Collective Action to Organized Collaboration?

    DEFF Research Database (Denmark)

    Hattke, Fabian; Blaschke, Steffen; Frost, Jetta

    2016-01-01

    internationalization. Based on our results, we suggest that, depending on the field of action, voluntary collective action and organized collaboration are substitutes with regard to performance. Our study contributes to the literature on collective action and to research on public organizations in pluralistic......Our study examines the relationship between voluntary collective action, organized collaboration, and the provision of public goods in pluralistic organizations. Using German higher education as a context, we investigate whether specialized central support structures contribute to performance...... in three fields of action: the training of young scientists, internationalization, and gender diversity. The findings indicate that organized collaboration may lead to improved performance in the training of young scientists and gender diversity. Conversely, voluntary collective action enhances...

  14. Voluntary reporting of greenhouse gases, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    The Voluntary Reporting Program for greenhouse gases is part of an attempt by the U.S. Government to develop innovative, low-cost, and nonregulatory approaches to limit emissions of greenhouse gases. It is one element in an array of such programs introduced in recent years as part of the effort being made by the United States to comply with its national commitment to stabilize emissions of greenhouse gases under the Framework Convention on Climate Change. The Voluntary Reporting Program, developed pursuant to Section 1605(b) of the Energy Policy Act of 1992, permits corporations, government agencies, households, and voluntary organizations to report to the Energy Information Administration (EIA) on actions taken that have reduced or avoided emissions of greenhouse gases.

  15. Why is the force-velocity relationship in leg press tasks quasi-linear rather than hyperbolic?

    Science.gov (United States)

    Bobbert, Maarten F

    2012-06-01

    Force-velocity relationships reported in the literature for functional tasks involving a combination of joint rotations tend to be quasi-linear. The purpose of this study was to explain why they are not hyperbolic, like Hill's relationship. For this purpose, a leg press task was simulated with a musculoskeletal model of the human leg, which had stimulation of knee extensor muscles as only independent input. In the task the ankles moved linearly, away from the hips, against an imposed external force that was reduced over contractions from 95 to 5% of the maximum isometric value. Contractions started at 70% of leg length, and force and velocity values were extracted when 80% of leg length was reached. It was shown that the relationship between leg extension velocity and external force was quasi-linear, while the relationship between leg extension velocity and muscle force was hyperbolic. The discrepancy was explained by the fact that segmental dynamics canceled more and more of the muscle force as the external force was further reduced and velocity became higher. External power output peaked when the imposed external force was ∼50% of maximum, while muscle power output peaked when the imposed force was only ∼15% of maximum; in the latter case ∼70% of muscle power was buffered by the leg segments. According to the results of this study, there is no need to appeal to neural mechanisms to explain why, in leg press tasks, the force-velocity relationship is quasi-linear rather than hyperbolic.

  16. Hemochromatosis Patients as Voluntary Blood Donors

    Directory of Open Access Journals (Sweden)

    Tara E Power

    2004-01-01

    Full Text Available The present study was designed to investigate hemochromatosis patients' suitability as blood donors as well as their perceptions and experience with the current public donation system. Participants were gathered from a list of current hemochromatosis patients (n=120 and members of the Canadian Hemochromatosis Society (n=1000. Of the 1120 surveys mailed out to these groups, 801 surveys were returned completed. The sample respondents had a mean age of 57.44 years (SD=12.73; range 19 to 87 years, and 57% were men. It was found that 20% (160 of the respondents have donated blood since their diagnosis; however, only 12% of the respondents indicated that they use voluntary blood donation as a means of maintaining their iron levels. Forty per cent of the respondents indicated that they had been refused from voluntary donation. Despite the fact that in May 2001 the Canadian Blood Services, in collaboration with the Canadian Hemochromatosis Society, began a promotion campaign to encourage hemochromatosis patients to become voluntary blood donors, the present study found that 15% of the respondents reported having been refused from the voluntary blood donation service due to the diagnosis of hemochromatosis. With respect to quality of life, it was found that individuals who donate blood were generally healthier with respect to physical functioning and bodily pain, however, these findings may indicate that hemochromatosis patients who are healthier are better able to donate at public blood banks, rather than that voluntary blood donation has an effect on the donors' physical functioning over phlebotomy clinic users. These study findings suggest that although there may be other medical factors limiting individuals from donating, hemochromatosis patients are interested in being voluntary blood donors and this potential resource is currently under-used.

  17. Restless legs syndrome and periodic leg movements in patients with movement disorders: Specific considerations.

    Science.gov (United States)

    Högl, Birgit; Stefani, Ambra

    2017-05-01

    Restless legs syndrome is a frequent neurological disorder with potentially serious and highly distressing treatment complications. The role and potential implications of periodic leg movements during sleep range from being a genetic risk marker for restless legs syndrome to being a cardiovascular risk factor. The diagnosis of restless legs syndrome in patients with daytime movement disorders is challenging and restless legs syndrome needs to be differentiated from other sleep-related movement disorders. This article provides an update on the diagnosis of restless legs syndrome as an independent disorder and the role of periodic leg movements and reviews the association of restless legs syndrome with Parkinson's disease and other movement disorders. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.

  18. LegC3, an effector protein from Legionella pneumophila, inhibits homotypic yeast vacuole fusion in vivo and in vitro.

    Directory of Open Access Journals (Sweden)

    Terry L Bennett

    Full Text Available During infection, the intracellular pathogenic bacterium Legionella pneumophila causes an extensive remodeling of host membrane trafficking pathways, both in the construction of a replication-competent vacuole comprised of ER-derived vesicles and plasma membrane components, and in the inhibition of normal phagosome:endosome/lysosome fusion pathways. Here, we identify the LegC3 secreted effector protein from L. pneumophila as able to inhibit a SNARE- and Rab GTPase-dependent membrane fusion pathway in vitro, the homotypic fusion of yeast vacuoles (lysosomes. This vacuole fusion inhibition appeared to be specific, as similar secreted coiled-coiled domain containing proteins from L. pneumophila, LegC7/YlfA and LegC2/YlfB, did not inhibit vacuole fusion. The LegC3-mediated fusion inhibition was reversible by a yeast cytosolic extract, as well as by a purified soluble SNARE, Vam7p. LegC3 blocked the formation of trans-SNARE complexes during vacuole fusion, although we did not detect a direct interaction of LegC3 with the vacuolar SNARE protein complexes required for fusion. Additionally, LegC3 was incapable of inhibiting a defined synthetic model of vacuolar SNARE-driven membrane fusion, further suggesting that LegC3 does not directly inhibit the activity of vacuolar SNAREs, HOPS complex, or Sec17p/18p during membrane fusion. LegC3 is likely utilized by Legionella to modulate eukaryotic membrane fusion events during pathogenesis.

  19. Treatment of restless legs syndrome.

    Science.gov (United States)

    Comella, Cynthia L

    2014-01-01

    Restless legs syndrome (RLS) is a common disorder diagnosed by the clinical characteristics of restlessness in the legs associated often with abnormal sensations that start at rest and are improved by activity, occurring with a diurnal pattern of worsened symptoms at night and improvement in the morning. RLS is the cause of impaired quality of life in those more severely afflicted. Treatment of RLS has undergone considerable change over the last few years. Several classes of medications have demonstrated efficacy, including the dopaminergic agents and the alpha-2-delta ligands. Levodopa was the first dopaminergic agent found to be successful. However, chronic use of levodopa is frequently associated with augmentation that is defined as an earlier occurrence of symptoms frequently associated with worsening severity and sometimes spread to other body areas. The direct dopamine agonists, including ropinirole, pramipexole, and rotigotine patch, are also effective, although side effects, including daytime sleepiness, impulse control disorders, and augmentation, may limit usefulness. The alpha-2-delta ligands, including gabapentin, gabapentin enacarbil, and pregabalin, are effective for RLS without known occurrence of augmentation or impulse control disorders, although sedation and dizziness can occur. Other agents, including the opioids and clonazepam do not have sufficient evidence to recommend them as treatment for RLS, although in an individual patient, they may provide benefit.

  20. Targinact for restless legs syndrome.

    Science.gov (United States)

    2016-04-01

    Idiopathic restless legs syndrome (RLS)--also known as Willis-Ekbom disease--is a neurological condition characterised by an overwhelming urge to move the legs, occurring during rest or inactivity, especially at night. Symptoms are highly variable in frequency and severity, and can affect sleep and quality of life. First-line management includes addressing precipitating or aggravating factors and providing explanation, reassurance and advice on self-help strategies. Drug therapy (e.g. a dopamine agonist) is used for patients with more severe symptoms. In December 2014, the marketing authorisation for a modified-release preparation containing oxycodone and naloxone (Targinact-Napp Pharmaceuticals) was expanded to include use in the treatment of severe to very severe RLS after failure of dopaminergic therapy.(10)Here we review the management of adults with RLS, including the place of oxycodone/naloxone. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  1. The institutional dynamics of voluntary organisations

    DEFF Research Database (Denmark)

    Aagaard, Peter

    this theoretical frame to analyse case studies of three voluntary organisations.  As a part of the analysis I describe four sets of institutional settings that can influence voluntary organisations ability to create institutional dynamic: institutionalization, moderation, self-organisation and loose-coupling....... organisations. I establish a theoretical frame of institutional dynamic, build primarily on J.G. March's theory on exploration and exploitation. I focus on two organisational arrangements drawn from the theory: The degree of strategic decision-making and the degree of diversity among the volunteers. I use...

  2. Impairment of voluntary control of finger motion following stroke: role of inappropriate muscle coactivation.

    Science.gov (United States)

    Kamper, D G; Rymer, W Z

    2001-05-01

    Subjects with chronic hemiplegia following stroke attempted to perform voluntary isometric, isokinetic, and free contractions of the extensor muscles of the metacarpophalangeal (MCP) joints. We recorded torque, metacarpophalangeal joint angle and velocity, and electromyographic (EMG) activity of the extrinsic extensors and flexors and the first dorsal interosseous (FDI). We found that voluntary MCP joint extension in hemiparetic subjects was greatly impaired in comparison with control subjects: only two of the 11 stroke subjects were able to generate even 0.21 N-m of isometric extension torque, only two could produce positive finger extension with no load, and none could develop an isokinetic concentric extension. Deficits seemed to result from a combination of coactivation of the finger flexor and extensor muscles and decreased voluntary excitation of the extensors, as normalized flexor and FDI EMG activity were greater for stroke than for control subjects (P < 0.001), but normalized extensor activity was reduced (P < 0.001). Copyright 2001 John Wiley & Sons, Inc.

  3. Restless legs syndrome mimicking S1 radiculopathy.

    Science.gov (United States)

    Zambelis, Th; Wolgamuth, B R; Papoutsi, S N; Economou, N T

    2016-01-01

    Α case of a chronic idiopathic form of a severe type of Restless Legs Syndrome (RLS), which developed during pregnancy and persisted after this, misdiagnosed for 34 years as radiculopathy S1, is reported. In spite of the thorough clinical and laboratory investigation, in addition to constant changes of the therapeutic approach, the diagnosis of S1 radiculopathy could not be confirmed, resulting in a chronic clinical course; the latter was characterized by relapses and remissions not attributed or linked in any way to the treatment (various types of). In fact, it was due to a routine workup in a sleep clinic, where the patient was referred because of a coincident chronic insomnia (Restless Legs Syndrome is a known and important cause of insomnia/chronic insomnia), which resulted in a proper diagnosis and treatment of this case. With the use of Restless Legs Syndrome appropriate treatment (Pramipexole 0.18 mg taken at bedtime, a dopaminergic agent and Level A recommended drug for Restless Legs Syndrome) an excellent response and immediate elimination of symptoms was achieved. Restless Legs Syndrome may present with a variety of symptoms (with the most prominent shortly being reported with the acronym URGE: Urge to move the legs usually associated with unpleasant leg sensations, Rest induces symptoms, Getting active brings relief, Evening and night deteriorate symptoms); given the fact that Restless Legs Syndrome presents with a great variety and heterogeneity of symptoms (mostly pain, dysesthesia and paresthesia), which may occur in several other diseases (the so called "RLS mimics"), proper diagnosis of Restless Legs Syndrome usually fails. Restless Legs Syndrome misinterpreted as S1 radiculopathy, to the best of our knowledge, has not been reported yet in the literature. Here, case history, clinical course and common RLS mimics are presented. Different forms of Restless Legs Syndrome manifestations, which are commonly -as in this case- misinterpreted due to their

  4. 77 FR 72941 - Voluntary Education Programs

    Science.gov (United States)

    2012-12-07

    ... decision will be made by the selected DoD contractor for the complete `third party review' process. Comment... seeks to enhance the educational opportunities to Service members who may have difficulty in completing... transitions to second careers in teaching. Voluntary education programs. Continuing, adult, or...

  5. Decentralized trade with bargaining and voluntary matching

    DEFF Research Database (Denmark)

    Tranæs, Torben; Sloth, Birgitte; Hendon, Ebbe

    1994-01-01

    Rubinstein and Wolinsky (1990) study a market with one seller, two buyers, and voluntary matching. Both the competitive outcomepc and the bilateral bargaining outcomepb are possible in subgame perfect equilibrium. We consider two variations. First, if there is a cost larger thanpc−pc to the seller...

  6. Social orienting: reflexive versus voluntary control.

    Science.gov (United States)

    Hill, Julia L; Patel, Saumil; Gu, Xue; Seyedali, Nassim S; Bachevalier, Jocelyne; Sereno, Anne B

    2010-09-24

    Many studies have shown that the direction of gaze of a face covertly facilitates the response to a target presented in the matching direction. In this study we seek to determine whether there exist separate reflexive and voluntary forms of such covert social orienting and how they interact with each other. We measured the effect of the predictive value of a gaze cue on manual choice reaction times. When the predictive value of the gaze cue was zero, a facilitatory cueing effect was still observed which peaked at a cue onset to target onset delay (CTD) of 150ms and largely diminished beyond a CTD of 500ms. When the gaze cue was 100% predictive of the future location of the target, at CTDs greater than 200, the predictive cue resulted in a significantly greater facilitation of response than occurred with a non-predictive cue. These results suggest that given enough time (about 200ms), the social cue is interpreted and a willful or voluntary spatially-specific social cueing effect occurs. In addition, we found that a predictive cue resulted in a significant slowing of the observer's responses up to a CTD of 200ms. These findings show that, similar to non-social spatial orienting, there appear to be two forms of social orienting including a reflexive component and voluntary component. We suggest a model of social orienting in which the voluntary social orienting system modulates tonic inhibition of the reflexive social orienting system. Published by Elsevier Ltd.

  7. Equality, self‐respect and voluntary separation

    NARCIS (Netherlands)

    M.S. Merry

    2012-01-01

    This paper argues that self‐respect constitutes an important value, and further, an important basis for equality. It also argues that under conditions of inequality‐producing segregation, voluntary separation in schooling may be more likely to provide the resources necessary for self‐respect. A prim

  8. School Ethical Climate and Teachers' Voluntary Absence

    Science.gov (United States)

    Shapira-Lishchinsky, Orly; Rosenblatt, Zehava

    2010-01-01

    Purpose: This paper aims to offer a theoretical framework for linking school ethical climate with teachers' voluntary absence. The paper attempts to explain this relationship using the concept of affective organizational commitment. Design/methodology/approach: Participants were 1,016 school teachers from 35 high schools in Israel. Data were…

  9. Voluntary Oral Administration of Losartan in Rats.

    Science.gov (United States)

    Diogo, Lucília N; Faustino, Inês V; Afonso, Ricardo A; Pereira, Sofia A; Monteiro, Emília C; Santos, Ana I

    2015-09-01

    Gavage is a widely performed technique for daily dosing in laboratory rodents. Although effective, gavage comprises a sequence of potentially stressful procedures for laboratory animals that may introduce bias into experimental results, especially when the drugs to be tested interfere with stress-dependent parameters. We aimed to test vehicles suitable for drug delivery by voluntary ingestion in rats. Specifically, Male Wistar rats (age, 2 to 3 mo) were used to test nut paste (NUT), peanut butter (PB), and sugar paste (SUG) as vehicles for long-term voluntary oral administration of losartan, an angiotensin II receptor blocker. Vehicles were administered for 28 d without drug to assess effects on the glucose level and serum lipid profile. Losartan was mixed with vehicles and either offered to the rats or administered by gavage (14 d) for subsequent quantification of losartan plasma levels by HPLC. After a 2-d acclimation period, all rats voluntarily ate the vehicles, either alone or mixed with losartan. NUT administration reduced blood glucose levels. The SUG group had higher concentrations of losartan than did the gavage group, without changes in lipid and glucose profiles. Our results showed that NUT, PB, and SUG all are viable for daily single-dose voluntary ingestion of losartan and that SUG was the best alternative overall. Drug bioavailability was not reduced after voluntary ingestion, suggesting that this method is highly effective for chronic oral administration of losartan to laboratory rodents.

  10. Staff's perceptions of voluntary assertiveness skills training.

    Science.gov (United States)

    McVanel, Sarah; Morris, Beth

    2010-01-01

    Clinicians' ability to be assertive when unsure or concerned about procedures, treatment modalities, or patients' symptoms is key in reducing risk and preventing sentinel events. In this article, the authors provide a framework for generic, voluntary assertiveness communication skills workshops that any educator can implement.

  11. Voluntary Organizations: Commitment, Leadership, and Organizational Effectiveness

    Science.gov (United States)

    Ekeland, Terry P.

    2004-01-01

    Voluntary organizations offer a unique opportunity to interpret participant relationships, leadership influences, and organizational effectiveness unencumbered by employment relationships. Regardless of organizational structure or purpose, all organizations are affected to some degree by their leadership and their membership. Based on the…

  12. Environmental Voluntary Agreements in the Dutch Context

    NARCIS (Netherlands)

    Bressers, Johannes T.A.; de Bruijn, Theo; Croci, Edoardo

    2005-01-01

    This paper describes and analyses the use of environmental voluntary agreements, or covenants, in Dutch environmental policy. Covenants have become a widely used policy instrument in the Netherlands. This trend reinforces the strong neo-corporatist traits of Dutch society with its tendency towards

  13. Voluntary Community Organisations in Metropolitan Development

    DEFF Research Database (Denmark)

    Larsen, Jacob Norvig

    While short-term enrolling of citizens in urban regeneration projects often has proven quite successful, permanent embedding of projects in voluntary community-based settings seems to be much more difficult to obtain. This has implications for long term sustainability of urban regeneration projec...

  14. Eligibility and Exclusion of Hemochromatosis Patients as Voluntary Blood Donors

    Directory of Open Access Journals (Sweden)

    M Levstik

    1998-01-01

    Full Text Available BACKGROUND: Hereditary hemochromatosis patients are excluded in many countries as voluntary blood donors. In 1991, changes in the Canadian Red Cross policy allowed healthy hemochromatosis patients to become voluntary donors.

  15. Results of the global survey on Voluntary Sustainability Standards

    OpenAIRE

    Lernoud, Julia

    2015-01-01

    Results of the global survey on Voluntary Sustainability Standards: - Voluntary Sustainability Standards (VSS) area worldwide and selected commodities - Cocoa: Area growth by VSS 2008-2014 - Growth of VSS compliant area worldwide 2008-2013 (selected crops)

  16. China Initiates Voluntary Certification of Public Security Products

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ Reporters learned from the Certification and Accreditation Administration of China(CNCA)that burglar-proof door became the first batch of voluntary certification product in public security products.China has formally initiated voluntary certification of public security products.

  17. Voluntary sterilization in Serbia: Unmet need?

    Directory of Open Access Journals (Sweden)

    Rašević Mirjana M.

    2002-01-01

    Full Text Available Is voluntary sterilization as a birth control method accepted in Serbia? This is certainly a question that is being imposed for research, regardless of the fact that voluntary sterilization is neither accessible nor promoted. Most importantly because there is no understanding in the social nor political sphere for legalization of voluntary sterilization as a form of birth control, apart from the clear necessity for this, first, step. They are: the recognition that voluntary sterilization is an efficient and safe birth control method, respectability of basic human as well as sexual and reproductive rights, spreading of sterilization as a form of birth control among population of both developed and developing countries and an epidemic diffusion of repeated induced abortions in Serbia. Thus individual recognition of the advantages of relying on voluntary sterilization, in a non-encouraging atmosphere, certainly represents one more argument to enable couples to prevent conception by sterilization. Since it was impossible to carry out a representative research among the population of men and women who are at risk for conception, an attempt was made to obtain a reply to the set question among women who decided to induce abortion. It was done out of at least two reasons. The first being that women with induced abortion in their reproductive history were the target group for voluntary sterilization. The second reason was based on the assumption that bringing a decision on induced abortion is preceded by the reconsideration of an earlier adopted strategy regarding children, giving birth and contraception and thus its rational component is revealed more and therefore more easily measurable. The research was carried out in the University Clinic of Obstetrics and Gynecology 'Narodni front' in Belgrade from January 21st o March 1st 2002, and included 296 women. By comparing the social and demographic characteristics of the female respondents, as well as

  18. Why do flamingos stand on one leg?

    Science.gov (United States)

    Anderson, Matthew J; Williams, Sarah A

    2010-01-01

    A series of observational studies of captive Caribbean flamingos Phoenicopterus ruber were conducted to determine why flamingos rest on one leg. While frequently asked by the general public, this basic question has remained unanswered by the scientific community. Here we suggest that the latency of flamingos to initiate forward locomotion following resting on one leg is significantly longer than following resting on two, discounting the possibility that unipedal resting reduces muscle fatigue or enhances predatory escape. Additionally, we demonstrate that flamingos do not display lateral preferences at the individual or group levels when resting on one leg, with each bird dividing its resting time across both legs. We show that while flamingos prefer resting on one leg to two regardless of location, the percentage of birds resting on one leg is significantly higher among birds standing in the water than among those on land. Finally, we demonstrate a negative relationship between temperature and the percentage of observed birds resting on one leg, such that resting on one leg decreases as temperature rises. Results strongly suggest that unipedal resting aids flamingos in thermoregulation. (c) 2009 Wiley-Liss, Inc.

  19. X-Ray Exam: Femur (Upper Leg)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Femur (Upper Leg) KidsHealth > For Parents > X-Ray Exam: Femur (Upper Leg) A A A ... español Radiografía: fémur What It Is A femur X-ray is a safe and painless test that ...

  20. Ropinirole treatment for restless legs syndrome.

    Science.gov (United States)

    Molnar, Miklos Zsolt; Fornadi, Katalin; Shapiro, Colin M

    2006-09-01

    In this paper we discuss therapy with ropinirole (known as adartrel in the United Kingdom) in patients with restless legs syndrome. Restless legs syndrome is characterized by an urge to move the legs, uncomfortable sensations in the legs and worsening of these symptoms during rest with at least temporary relief brought on by activity. Current recommendations suggest dopaminergic therapy (levodopa or dopamine receptor agonists like ropinirole) as the first-line treatment for restless legs syndrome. Based on the results of randomized, placebo-controlled, double-blind trials, we conclude that ropinirole is effective in reducing symptoms of restless legs syndrome in the general population. Ropinirole has no serious or common side effects that would limit its use significantly. Rebound and augmentation problems are relatively rarely seen with ropinirole, although properly designed comparative trials are still needed to address this question. It must be noted, however, that most published studies with ropinirole compare this drug with placebo. Very few studies have compared ropinirole with other drugs (L-dopa, gabapentin, opioids, benzodiazepines, other dopaminergic agents and selegiline hydrochloride). No cost-effectiveness trial has been published yet. Treatment of restless legs syndrome with ropinirole shows it to be effective, well-tolerated and safe and it can be used in restless legs syndrome in general.

  1. Diagnosis and treatment of restless legs syndrome.

    Science.gov (United States)

    Sales, Samantha; Sanghera, Manjit K; Klocko, David J; Stewart, R Malcolm

    2016-07-01

    Restless legs syndrome (RLS) is a disorder characterized by an irresistible urge to move the legs during rest, usually accompanied by uncomfortable sensations in the affected extremity or extremities. RLS can manifest at any age but prevalence increases with advancing age. This article describes the symptoms of RLS, associated comorbidities, and how to diagnose and manage RLS.

  2. One-repetition maximum strength test represents a valid means to assess leg strength in vivo in humans.

    Science.gov (United States)

    Verdijk, Lex B; van Loon, Luc; Meijer, Kenneth; Savelberg, Hans H C M

    2009-01-01

    Skeletal muscle strength is often determined to evaluate the adaptive response to an exercise intervention programme. Although dynamometry is considered the "gold standard" for the assessment of muscle strength in vivo, one-repetition maximum (1-RM) testing performed on training-specific equipment is more commonly applied. We assessed the validity of specific knee extension 1-RM testing by comparison with dynamometry in a heterogeneous population (n=55). All participants performed 1-RM tests on regular leg extension and leg press machines. Additionally, isometric (at seven different knee angles) and isokinetic (at four different velocities) knee extension peak torques were determined. Pearson's r was calculated for the relationship between 1-RM data and peak torques for the entire population and for subgroups defined by age and gender. One-repetition maximum strength correlated strongly with the dynamometer results. One-repetition maximum leg extension correlated more strongly with peak torques than did 1-RM leg press (0.78leg muscle strength in vivo in young and elderly men and women. Considering the importance of training specificity in strength assessment, we argue that 1-RM testing can be applied to assess changes in leg muscle strength following an exercise intervention.

  3. Update in restless legs syndrome

    Science.gov (United States)

    Salas, Rachel E.; Gamaldo, Charlene E.; Allen, Richard P.

    2016-01-01

    Purpose of review Although restless legs syndrome (RLS) is a disorder recognized in the medical literature since the 17th century, there have only recently been significant clinical and scientific advances in diagnosis, epidemiology and understanding the disorder, mainly due to the advent of dopaminergic treatment. Recent findings Recent discoveries have uncovered the iron–dopamine connection in RLS and the basic dopaminergic pathology related to the RLS symptoms. These have led to new understanding of the morbidity of RLS and the many conditions associated with RLS, which have also supported new approaches to treatment. These developments are each briefly described here. Summary Although there has been progress in understanding, diagnosing and treating RLS, it remains an underdiagnosed and undertreated condition severely impairing functioning of patients with moderate-to-severe disease. Much work is needed to improve on current, as well as other novel therapies. PMID:20581683

  4. Opioids for restless legs syndrome.

    Science.gov (United States)

    de Oliveira, César Osório; Carvalho, Luciane Bc; Carlos, Karla; Conti, Cristiane; de Oliveira, Marcio M; Prado, Lucila Bf; Prado, Gilmar F

    2016-06-29

    Restless legs syndrome (RLS) is a distressing and common neurological disorder that may have a huge impact in the quality of life of those with frequent and intense symptoms. Patients complain of unpleasant sensations in the legs, at or before bedtime, and feel an urge to move the legs, which improves with movement, such as walking. Symptoms start with the patient at rest (e.g. sitting or lying down), and follow a circadian pattern, increasing during the evening or at night. Many pharmacological intervention are available for RLS, including drugs used to treat Parkinson's disease (L-Dopa and dopaminergic agonists), epilepsy (anticonvulsants), anxiety (benzodiazepines), and pain (opioids). Dopaminergic drugs are those most frequently used for treatment of RLS, but some patients do not respond effectively and require other medication. Opioids, a class of medications used to treat severe pain, seem to be effective in treating RLS symptoms, and are recommended for patients with severe symptoms, because RLS and pain appear to share the same mechanism in the central nervous system. All available drugs are associated to some degree with side effects, which can impede treatment. Opioids are associated with adverse events such as constipation, tolerance, and dependence. This justifies the conduct of a systematic review to ascertain whether opioids are safe and effective for treatment of RLS. To asses the effects of opioids compared to placebo treatment for restless legs syndrome in adults. We searched the Cochrane Central Register of Controlled trials, CENTRAL 2016, issue 4 and MEDLINE, EMBASE, and LILACS up to April 2016, using a search strategy adapted by Cochraneto identify randomised clinical trials. We checked the references of each study and established personal communication with other authors to identify any additional studies. We considered publications in all languages. Randomised controlled clinical trials of opioid treatment in adults with idiopathic RLS. Two

  5. Shewanella alga bacteremia in two patients with lower leg ulcers

    DEFF Research Database (Denmark)

    Domínguez, H.; Vogel, Birte Fonnesbech; Gram, Lone

    1996-01-01

    of infection. Both patients survived; however, one of them had extensive myonecrosis, while the other patient had an uncomplicated course. The strains were initially believed to be Shewanella putrefaciens on the basis of key characteristics and results of the API 20NE identification system (bioMerieux, Marcy l......The first Danish cases of Shewanella alga bacteremia in two patients with chronic lower leg ulcers are reported. Both patients were admitted to the hospital during the same month of a very warm summer and had been exposed to the same marine environment, thereby suggesting the same source......'Etoile, France), but further genetic and physiological analyses identified them as Shewanella alga....

  6. Crypsis via leg clustering: twig masquerading in a spider.

    Science.gov (United States)

    Zhang, Shichang; Mao, Kuei-Kai; Lin, Po-Ting; Ho, Chiu-Ju; Hung, Wei; Piorkowski, Dakota; Liao, Chen-Pan; Tso, I-Min

    2015-03-01

    The role of background matching in camouflage has been extensively studied. However, contour modification has received far less attention, especially in twig-mimicking species. Here, we studied this deceptive strategy by revealing a special masquerade tactic, in which the animals protract and cluster their legs linearly in the same axis with their bodies when resting, using the spider Ariamnes cylindrogaster as a model. We used cardboard papers to construct dummies resembling spiders in appearance and colour. To differentiate the most important factors in the concealment effect, we manipulated body size (long or short abdomen) and resting postures (leg clustered or spread) of the dummies and recorded the responses of predators to different dummy types in the field. The results showed that dummies with clustered legs received significantly less attention from predators, regardless of the body length. Thus, we conclude that A. cylindrogaster relies on the resting posture rather than body size for predator avoidance. This study provides, to the best of our knowledge, empirical evidence for the first time that twig-mimicking species can achieve effective camouflage by contour modification.

  7. Intensive treatment of leg lymphedema

    Directory of Open Access Journals (Sweden)

    Pereira de Godoy Jose

    2010-01-01

    Full Text Available Background: Despite of all the problems caused by lymphedema, this disease continues to affect millions of people worldwide. Thus, the identification of the most efficacious forms of treatment is necessary. Aim: The aim of this study was to evaluate a novel intensive outpatient treatment for leg lymphedema. Methods: Twenty-three legs of 19 patients were evaluated in a prospective randomized study. The inclusion criteria were patients with Grade II and III lymphedema, where the difference, measured by volumetry, between the affected limb below the knee and the healthy limb was greater than 1.5 kg. Intensive treatment was carried out for 6- to 8-h sessions in the outpatient clinic. Analysis of variance was utilized for statistical analysis with an alpha error of 5% (P-value < 0.05 being considered significant. Results: All limbs had significant reductions in size with the final mean loss being 81.1% of the volume of edema. The greatest losses occurred in the first week (P-value < 0.001. Losses of more than 90% of the lymphedema occurred in 9 (39.13% patients; losses of more than 80% in 13 (56.52%, losses of more than 70% in 17 (73.91% and losses of more than 50% were recorded for 95.65% of the patients; only 1 patient lost less than 50% (37.9% of the edema. Conclusion: The intensive treatment of lymphedema in the outpatient clinic can produce significant reductions in the volume of edema over a short period of time and can be recommended for any grade of lymphedema, in particular the more advanced degrees.

  8. Moving from voluntary euthanasia to non-voluntary euthanasia: equality and compassion.

    Science.gov (United States)

    Amaraskekara, Kumar; Bagaric, Mirko

    2004-09-01

    The recent Dutch law legalising active voluntary euthanasia will reignite the euthanasia debate. An illuminating method for evaluating the moral status of a practice is to follow the implications of the practice to its logical conclusion. The argument for compassion is one of the central arguments in favour of voluntary active euthanasia. This argument applies perhaps even more forcefully in relation to incompetent patients. If active voluntary euthanasia is legalised, arguments based on compassion and equality will be directed towards legalising active non-voluntary euthanasia in order to make accelerated termination of death available also to the incompetent. The removal of discrimination against the incompetent has the potential to become as potent a catch-cry as the right to die. However, the legalisation of non-voluntary euthanasia is undesirable. A review of the relevant authorities reveals that there is no coherent and workable "best interests" test which can be invoked to decide whether an incompetent patient is better off dead. This provides a strong reason for not stepping onto the slippery path of permitting active voluntary euthanasia.

  9. 5 CFR 919.1020 - Voluntary exclusion or voluntarily excluded.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Voluntary exclusion or voluntarily excluded. 919.1020 Section 919.1020 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED...) Definitions § 919.1020 Voluntary exclusion or voluntarily excluded. (a) Voluntary exclusion means a person's...

  10. 37 CFR 351.2 - Voluntary negotiation period; settlement.

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Voluntary negotiation period... CONGRESS COPYRIGHT ROYALTY JUDGES RULES AND PROCEDURES PROCEEDINGS § 351.2 Voluntary negotiation period..., the Copyright Royalty Judges will announce the beginning of a voluntary negotiation period and...

  11. 15 CFR 12.3 - Development of voluntary product standards.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Development of voluntary product... AND LABELING § 12.3 Development of voluntary product standards. (a) Invitation to participate in the development of a voluntary product standard. Whenever the Secretary publishes a final determination of...

  12. Neurobiology: reconstructing the neural control of leg coordination.

    Science.gov (United States)

    Zill, Sasha N; Keller, Bridget R

    2009-05-12

    Walking is adaptable because the timing of movements of individual legs can be varied while maintaining leg coordination. Recent work in stick insects shows that leg coordination set by interactions of pattern generating circuits can be overridden by sensory feedback.

  13. Influence of trunk muscle co-contraction on spinal curvature during sitting cross-legged.

    Science.gov (United States)

    Watanabe, S; Kobara, K; Ishida, H; Eguchi, A

    2010-01-01

    In Asia, many activities of daily living (ADL) are performed while sitting cross-legged on the floor. This sitting posture rotates the pelvis in a more dorsal direction and lumbar lordosis is more flattened than while sitting on a chair. Sitting cross-legged induces a greater load on the intervertebral discs and spine, especially when in a slumped position that is known to increase disc pressure even more and to aggravate chronic low back pain (CLBP). Therefore, it is very important to instruct Asian people about the correct sitting posture. In addition, it is known that co-contraction of the deep spine-stabilizing muscles enhances lumbar segmental stability and the sacroiliac joint. However, little is known about the influence of co-contraction of the trunk deep muscles on spinal curvature while sitting cross-legged on the floor. The purpose of this study was to compare EMG (electromyographic) activity of the trunk muscles while slump cross-legged sitting with that during co-contraction of the trunk muscles and to investigate how this co-contraction influences spinal curvature. Ten healthy male volunteers (21.7 +/- 2.5 years old) without CLBP participated in the study. Bipolar surface electrodes were attached to the rectus abdominis, the obliquus externus abdominis, the obliquus internus abdominis, the lower back extensor muscles (L3) and the multifidus on the right side. EMG signals were continuously recorded while slump sitting cross-legged and during co-contraction of the trunk muscles. They were amplified, band-pass filtered, digitized and stored by a data acquisition system. The average muscle activity values over the five-second sample for each sitting posture were normalized to maximal voluntary contractions (%MVC). While the subjects performed both sitting postures, the curvature of the spine was measured using a skin-surface and hand-held device, the "Spinal Mouse". More significant activities of the trunk muscles, with the exception of the rectus

  14. Bottom-"wide" Approach to Climate Change - Typology and Analysis on Climate Vulnerability Reduction through Voluntary Actions

    Directory of Open Access Journals (Sweden)

    Kiyoto Yamaura

    2013-07-01

    Full Text Available Climate change risk is mostly and often unfairly cast upon those who are vulnerable. As one of the effective and spreadable means in reducing human vulnerability to climate change, this paper and its findings address the role, strength and limitations of voluntary actions. Through an extensive review of various climate change literature, projects and interviews among practitioners, the authors looked at thetypes of interventions and results that voluntary actions have achieved. The paperintroducesvarious types of voluntary activities such as awareness raising, community mobilization and empowerment, community-based adaptation and mitigation, and voluntary environmental regulations and schemes. Such bottom-"wide" approach to climate change is closely linked with civil environmentalism with broad focus and also scientifically strengthened by its engagement with civic science. It urges shifting the mind-set of international development agencies to flexibly accommodate and maximize the potential of voluntary, bottom-wide actions in combating climate change. Finally, the paper lists out pieces of recommendation to further improve and fully utilize voluntary actions in reducing vulnerabilityon the ground, by emphasizing long-term orientation, capacity development, monitoring and evaluation and building partnerships at the local level.

  15. Arm movements can increase leg muscle activity during submaximal recumbent stepping in neurologically intact individuals.

    Science.gov (United States)

    de Kam, Digna; Rijken, Hennie; Manintveld, Toos; Nienhuis, Bart; Dietz, Volker; Duysens, Jacques

    2013-07-01

    Facilitation of leg muscle activity by active arm movements during locomotor tasks could be beneficial during gait rehabilitation after spinal cord injury. The present study explored the effects of arm movements on leg muscle activity during submaximal recumbent stepping. Healthy subjects exercised on a recumbent stepping machine both with and without arm movements. Activity of five leg muscles was recorded and compared for stepping with and without arm movements. To determine which arm movements are optimal for leg muscle facilitation, subjects were instructed to step with 1) mechanically coupled vs. decoupled arm and leg movements, 2) synchronous vs. asynchronous arm movements, and 3) at 50 vs. 70 RPM. Leg muscle activity was increased by active arm movements in all muscles, except the vastus lateralis muscle. Activity of other extensors (soleus, medial gastrocnemius, and biceps femoris) was primarily increased during the extension phase, whereas activity of flexors (tibialis anterior) was also increased during the flexion phase. Facilitation was more or less consistent for both frequencies and for synchronous and asynchronous movements. For coupled arm movements, facilitation tended to be diminished or absent. The observed facilitation in the present study is probably of neuromuscular rather than biomechanical origin, since the arms are probably hardly involved in postural control or weight-bearing during recumbent stepping. Further studies in patients should explore the possibility to integrate neuromuscular facilitation in rehabilitation programs.

  16. Towards a bio-inspired leg design for high-speed running.

    Science.gov (United States)

    Ananthanarayanan, Arvind; Azadi, Mojtaba; Kim, Sangbae

    2012-12-01

    High-speed terrestrial locomotion inevitably involves high acceleration and extensive loadings on the legs. This imposes a challenging trade-off between weight and strength in leg design. This paper introduces a new design paradigm for a robotic leg inspired by musculoskeletal structures. The central hypothesis is that employing a tendon-bone co-location architecture not only provides compliance in the leg, but can also reduce bone stresses caused by bending on structures. This hypothesis is applied to a leg design, and verified by simulations and the experiments on a prototype. In addition, we also present an optimization scheme to maximize the strength to weight ratio. Using the tendon-bone co-location architecture, the stress on the bone during a stride is reduced by up to 59%. A new foam-core prototyping technique enables creating structural characteristics similar to mammalian bones in the robotic leg. This method allows us to use lighter polymeric structures that are cheaper and quicker to fabricate than conventional fabrication methods, and can eventually greatly shorten the design iteration cycle time.

  17. Positioning the hip with respect to the COM: Consequences for leg operation.

    Science.gov (United States)

    Blickhan, Reinhard; Andrada, Emanuel; Müller, Roy; Rode, Christian; Ogihara, Naomichi

    2015-10-07

    In bipedal runners and hoppers the hip is not located at the center of mass in the sagittal projection. This displacement influences operation and energetics of the leg attached to the hip. To investigate this influence in a first step a simple conservative bouncing template is developed in which a heavy trunk is suspended to a massless spring at a pivot point above the center of mass. This model describes the orientation of the ground reaction forces observed in experiments on running birds. In a second step it is assumed that an effective telescope leg with its hip fixed to the trunk remote from the COM generates the same ground reaction forces as those predicted by the template. For this effective leg the influence of hip placement on leg operation and energetics is investigated. Placing the hip directly below, at, or above the pivot point results in high axial energy storage. Posterior placement increases axial losses and hip work whereas anterior placement would require axial work and absorption at the hip. Shifting the hip far posteriorly as observed in some birds can lead to the production of pure extension torques throughout the stance phase. It is proposed that the relative placement of the hip with respect to the center of mass is an important measure to modify effective leg operation with possible implications for balancing the trunk and the control of legged motion systems.

  18. Voluntary low-force contraction elicits prolonged low-frequency fatigue and changes in surface electromyography and mechanomyography

    DEFF Research Database (Denmark)

    Blangsted, Anne Katrine; Sjøgaard, Gisela; Madeleine, Pascal

    2005-01-01

    ) and in particular mechanomyography (MMG) during low-force rather than high-force test contractions. Seven subjects performed static wrist extension at 10% maximal voluntary contraction (MVC) for 10 min (10%MVC10 min). Wrist force response to electrical stimulation of extensor carpi radialis muscle (ECR) quantified...

  19. Burrowing as a novel voluntary strength training method for mice : A comparison of various voluntary strength or resistance exercise methods

    NARCIS (Netherlands)

    Roemers, P; Mazzola, P N; De Deyn, P P; Bossers, W J; van Heuvelen, M J G; van der Zee, E A

    2017-01-01

    BACKGROUND: Voluntary strength training methods for rodents are necessary to investigate the effects of strength training on cognition and the brain. However, few voluntary methods are available. NEW METHOD: The current study tested functional and muscular effects of two novel voluntary strength

  20. Expansion Compression Contacts for Thermoelectric Legs

    Science.gov (United States)

    Sakamoto, Jeffrey

    2009-01-01

    In a proposed alternative to previous approaches to making hot-shoe contacts to the legs of thermoelectric devices, one relies on differential thermal expansion to increase contact pressures for the purpose of reducing the electrical resistances of contacts as temperatures increase. The proposed approach is particularly applicable to thermoelectric devices containing p-type (positive-charge-carrier) legs made of a Zintl compound (specifically, Yb14MnSb11) and n-type (negative charge-carrier) legs made of SiGe. This combination of thermoelectric materials has been selected for further development, primarily on the basis of projected thermoelectric performance. However, it is problematic to integrate, into a practical thermoelectric device, legs made of these materials along with a metal or semiconductor hot shoe that is required to be in thermal and electrical contact with the legs. This is partly because of the thermal-expansion mismatch of these materials: The coefficient of thermal expansion (CTE) of SiGe is 4.5 x 10(exp -6) C (exp -1), while the CTE of Yb14MnSb11 is 20 x 10(exp -6) C(exp -1). Simply joining a Yb14MnSb11 and a SiGe leg to a common hot shoe could be expected to result in significant thermal stresses in either or both legs during operation. Heretofore, such thermal stresses have been regarded as disadvantageous. In the proposed approach, stresses resulting from the CTE mismatch would be turned to advantage.

  1. Cardiorespiratory, metabolic, and biomechanical responses during functional electrical stimulation leg exercise: health and fitness benefits.

    Science.gov (United States)

    Davis, Glen M; Hamzaid, Nur A; Fornusek, Ché

    2008-08-01

    Functional electrical stimulation (FES)-induced leg exercise offers the potential for individuals with lower-limb paralysis to otherwise gain some benefits conferred by leg exercise. Although its original intent is to reactivate the leg muscles to produce functional upright mobility, as a rehabilitation therapy, FES-evoked exercise increases the whole-body metabolism of individuals with spinal cord injury (SCI) so that they may gain general and localized health and fitness benefits. The physiological and psychosocial responses during FES-evoked cycling, standing, rowing, leg extension, or stepping have been extensively explored for over 20 years. Some of the advantages of such exercise include augmented cardiorespiratory fitness, promotion of leg blood circulation, increased activity of specific metabolic enzymes or hormones, greater muscle volume and fiber size, enhanced functional exercise capacity such as strength and endurance, and altered bone mineral density. Positive psychosocial adaptations have also been reported among SCI individuals who undergo FES exercise. This article presents a position review of the available literature on the effects of FES-evoked exercise since the earliest date until 2007, to warrant a conclusion about the current status and potential of FES-evoked exercise for paralyzed people.

  2. The relationship of leg volume and leg mass with anaerobic performance and knee strength in wrestlers

    Directory of Open Access Journals (Sweden)

    Erdal ZORBA

    2010-01-01

    Full Text Available The purpose of the present study was to determination of the relationship between leg volume, leg mass with anaerobic performance and knee strength in wrestlers. 31 wrestlers from a university students participated in this study voluntarily (age: 21.09 ± 0.99 yrs. Circumferential measurement were used for the determination of leg volume by Frustum Method and after that, a regression formula was used. For this formulas, while the R square (R2 value was .95 and the standart error value was .056. Leg mass was determined by the Hanavan Method. Wingate Anaerobic Power Test (WAnT was used for the determination of anaerobic performance and Isometric Knee Dynamometer was used for the determination of knee strength. Results of Pearson Product Moment correlation analysis, leg volume was significantly correlated with leg mass (r=.993; p<0.01, peak power (r=.523; p<0.01 and mean power (r=.585; p<0.01. Similarly leg mass was significantly correlated with peak power (r=.654; p<0.01 and mean power (r=.704; p<0.01. In addition, peak power was found to be significantly correlated with leg strength (r=.430; p<0.05 and mean power (r=.613; p<0.01. As a conclusion, the findings of the present study indicated that leg volume and leg mass plays important role in anaerobic performance in wrestlers and isometric knee strength was found to be correlated with anaerobic performance.

  3. Voluntary reporting of greenhouse gases 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    The Voluntary Reporting of Greenhouse Gases Program, required by Section 1605(b) of the Energy Policy Act of 1992, records the results of voluntary measures to reduce, avoid, or sequester greenhouse gas emissions. In 1998, 156 US companies and other organizations reported to the Energy information Administration that, during 1997, they had achieved greenhouse gas emission reductions and carbon sequestration equivalent to 166 million tons of carbon dioxide, or about 2.5% of total US emissions for the year. For the 1,229 emission reduction projects reported, reductions usually were measured by comparing an estimate of actual emissions with an estimate of what emissions would have been had the project not been implemented.

  4. Voluntary simulation workshops in nursing education

    DEFF Research Database (Denmark)

    Selberg, Hanne; Nielsen, Mette Elisabeth

    2012-01-01

    Voluntary simulation workshops in nursing education Hanne Selberg1, Mette Elisabeth Nielsen1, Mette Wenzel Horsted2, Karen Bertelsen2, Marianne Linnet Rasmussen2,Rikke Lohmann Panton3, Copenhagen, Mette Kjeldal Jensen4 Background Changes in nursing education in Denmark towards an academic approach...... with more theory and less practical training have resulted in discussions regarding the lack of practical skills amongst novice nurses. A Danish study of students’ drop-out from the nursing education indicates that difficulties in combining theory and practice are one of the motivating factors behind...... the students’ decision to drop out (Jensen et al. 2008). Within the past year our faculty has conducted several projects with the aim of integrating simulation into the curriculum. Furthermore, voluntary simulation workshop has been carried out as an additional offer in the nursing education. The purpose has...

  5. The Political Importance of Voluntary Work.

    Science.gov (United States)

    Kunneman, Harry

    This paper aims to develop a complex articulation of the civic meaningfulness of voluntary work that clarifies its political importance as a countervailing narrative pointing beyond dominant neoliberal and consumptive articulations of a good life. To start with, it sketches a hermeneutic perspective on civic meaningfulness based on the work of Paul Ricoeur. Subsequently, it introduces the ideas of 'ethical complexity', 'epistemological complexity' and 'diapoiesis', building on insights from critical complexity thinking and relational biology. It argues that these notions can provide a bridge between hermeneutic perspectives on meaning and values, on the one hand, and questions of meaning and values on the level of scientific and technological developments and within professional organizations, on the other. Thus a broader, more complex picture emerges of the civic meaningfulness of voluntary work in our times.

  6. Voluntary Management Earnings Forecasts and Discretionary Accruals

    DEFF Research Database (Denmark)

    Gramlich, Jeffrey; Sørensen, Ole Vagn

    2004-01-01

    This paper seeks to determine whether Danish managers exercise discretionary accruals to reach earnings forecast targets they voluntarily specify in conjunction with initial public offerings (IPOs). Because the Danish accounting and legal environment is more permissive than the US, we use Denmark...... as a natural laboratory for learning how business would occur without strict rules, enforcement and sanctions. Danish managers often volunteer pro forma financial statements for results that are expected to occur subsequent to the IPO. We examine a sample of 58 Danish firms that issue voluntary management...... earnings forecasts in connection with IPOs that occur between 1984 and 1996. The evidence we uncover strongly suggests that pre-managed earnings are adjusted toward these targets. In contrast with Kasznik's (1999 Kasznik, R. (1999). On the association between voluntary disclosure and earnings management...

  7. Factors that affect voluntary vaccination of children in Japan.

    Science.gov (United States)

    Shono, Aiko; Kondo, Masahide

    2015-03-10

    Some important vaccinations are not included in the routine childhood immunization schedule in Japan. Voluntary vaccinations are usually paid as an out-of-pocket expense. Low voluntary vaccination coverage rates and high target disease incidence are assumed to be a consequence of voluntary vaccination. Therefore, this study aimed to explore factors associated with voluntary vaccination patterns in children. We conducted an online survey of 1243 mothers from a registered survey panel who had at least one child 2 months to vaccination mainly correlated positively with annual household income and mothers' positive opinions about voluntary vaccinations, but negatively with number of children. Financial support, especially for low income households and households with more than one child, may motivate parents to vaccinate their children. Communication is also an important issue. More opportunities for education and information about voluntary vaccinations should be provided to mothers without distinguishing between voluntary and routine vaccination.

  8. Startle activation is additive with voluntary cortical activation irrespective of stimulus modality.

    Science.gov (United States)

    Maslovat, Dana; Drummond, Neil M; Carter, Michael J; Carlsen, Anthony N

    2015-10-01

    When a startling acoustic stimulus (SAS) is presented during a simple reaction time (RT) task, it can trigger the prepared response through an involuntary initiation pathway. Previous research modelling the effects of presenting a SAS at various intervals following a non-startling auditory imperative signal (IS) suggested that involuntary initiation-related neural activation is additive with the voluntary initiation processes. The current study tested the predictions of this additive model when the SAS and IS are of different modalities by using a visual rather than auditory go-signal. Because voluntary RT latencies are delayed for visual stimuli compared to acoustic stimuli, it was hypothesised that the time course of additive activation would be similarly delayed. Participants performed 150 RT trials requiring a targeted 20° wrist extension task with a SAS presented 0-125 ms following a visual go-signal. Results were not different to those predicted by an additive model (p=0.979), yet were significantly different to those predicted by a horse-race model (p=0.037), indicating a joint contribution of voluntary and involuntary activation, even when the IS and SAS are of different modalities. Furthermore, the results indicated that voluntary RT differences due to stimulus modality are attributable to processes that occur prior to the increase in initiation-related activation.

  9. Transiliac Leg Lengthening in Poliomyelitis

    Directory of Open Access Journals (Sweden)

    Baghdadi Taghi

    2009-10-01

    Full Text Available The development and widespread use of a prophylactic vaccine significantly reduced the incidence of poliomyelitis. At present we more commonly encounter with poliomyelitis sequelae especially in developing countries. We evaluate the results of a modified innominate osteotomy for leg length discrepancy in poliomyelitis. Instead of triangular bone graft as in Salter’s innominate osteotomy , a trapezoidal bone graft from the ilium is inserted in the site of osteotomy after gradual distraction of the limb. 25 patients (9 males and 16 females with mean age of 25 years (17-37 years were treated by this method. All of them had poliomyelitis with limb shortening. At a mean follow-up of 7 years (3 months to 17 years an average of 3 cm (2.5-3.5 was achieved. Complication was seen in three patients including injury to the lateral cutaneouns nerve of thigh and displacement of osteotomy in two patients .except in one all of the patients satisfied with the operation. We believe this method is safe, effective and cost-benefit for treating of moderate shortening of the lower limb in poliomyelitis.

  10. Pharmacotherapy for restless legs syndrome.

    Science.gov (United States)

    Ferini-Strambi, Luigi; Marelli, Sara

    2014-06-01

    Restless legs syndrome (RLS) is a common condition characterized by paresthesia and an urge to move. Predominantly, symptoms occur at rest in the evening or at night, and they are alleviated by moving the affected extremity. RLS prevalence in the general population has been estimated to be approximately 5%. This review presents all options for the treatment of RLS. Pharmacological treatment should be limited to those patients who suffer from clinically relevant RLS, that is, when symptoms impair the patient's quality of life, daytime functioning, social functioning or sleep. Treatment on demand is a clinical need in some RLS patients, and medications include carbidopa/levodopa, pramipexole, ropinirole, oxycodone, methadone, codeine and tramadol. Chronic RLS should be treated with either a nonergot dopamine agonist or an α-2-δ calcium channel ligand. A dopamine agonist is a more appropriate choice in the presence of depression and overweight. As α-2-δ ligands can alleviate chronic pain and may be helpful in treating anxiety and insomnia, the presence of any of these comorbidities may favor their use. For RLS present through much of the day and night, the use of long-acting agents, such as the rotigotine patch or gabapentin enacarbil should be considered. In refractory RLS, oral prolonged release oxycodone-naloxone should be considered.

  11. Mitigating greenhouse gas emissions: Voluntary reporting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-01

    The Voluntary Reporting Program, developed pursuant to Section 1605(b) of the Energy Policy Act of 1992, permits corporations, government agencies, households, and voluntary organizations to report on their emissions of greenhouse gases, and on actions taken that have reduced or avoided emissions or sequestered carbon, to the Energy Information Administration (EIA). This, the second annual report of the Voluntary Reporting Program, describes information provided by the participating organizations on their aggregate emissions and emissions reductions, as well as their emissions reduction or avoidance projects, through 1995. This information has been compiled into a database that includes reports from 142 organizations and descriptions of 967 projects that either reduced greenhouse gas emissions or sequestered carbon. Fifty-one reporters also provided estimates of emissions, and emissions reductions achieved, for their entire organizations. The projects described actions taken to reduce emissions of carbon dioxide from energy production and use; to reduce methane and nitrous oxide emissions from energy use, waste management, and agricultural processes; to reduce emissions of halocarbons, such as CFCs and their replacements; and to increase carbon sequestration.

  12. Voluntary Green Power Market Forecast through 2015

    Energy Technology Data Exchange (ETDEWEB)

    Bird, L.; Holt, E.; Sumner, J.; Kreycik, C.

    2010-05-01

    Various factors influence the development of the voluntary 'green' power market--the market in which consumers purchase or produce power from non-polluting, renewable energy sources. These factors include climate policies, renewable portfolio standards (RPS), renewable energy prices, consumers' interest in purchasing green power, and utilities' interest in promoting existing programs and in offering new green options. This report presents estimates of voluntary market demand for green power through 2015 that were made using historical data and three scenarios: low-growth, high-growth, and negative-policy impacts. The resulting forecast projects the total voluntary demand for renewable energy in 2015 to range from 63 million MWh annually in the low case scenario to 157 million MWh annually in the high case scenario, representing an approximately 2.5-fold difference. The negative-policy impacts scenario reflects a market size of 24 million MWh. Several key uncertainties affect the results of this forecast, including uncertainties related to growth assumptions, the impacts that policy may have on the market, the price and competitiveness of renewable generation, and the level of interest that utilities have in offering and promoting green power products.

  13. Hip proprioceptors preferentially modulate reflexes of the leg in human spinal cord injury.

    Science.gov (United States)

    Onushko, Tanya; Hyngstrom, Allison; Schmit, Brian D

    2013-07-01

    Stretch-sensitive afferent feedback from hip muscles has been shown to trigger long-lasting, multijoint reflex responses in people with chronic spinal cord injury (SCI). These reflexes could have important implications for control of leg movements during functional activities, such as walking. Because the control of leg movement relies on reflex regulation at all joints of the limb, we sought to determine whether stretch of hip muscles modulates reflex activity at the knee and ankle and, conversely, whether knee and ankle stretch afferents affect hip-triggered reflexes. A custom-built servomotor apparatus was used to stretch the hip muscles in nine chronic SCI subjects by oscillating the legs about the hip joint bilaterally from 10° of extension to 40° flexion. To test whether stretch-related feedback from the knee or ankle would be affected by hip movement, patellar tendon percussions and Achilles tendon vibration were delivered when the hip was either extending or flexing. Surface electromyograms (EMGs) and joint torques were recorded from both legs. Patellar tendon percussions and Achilles tendon vibration both elicited reflex responses local to the knee or ankle, respectively, and did not influence reflex responses observed at the hip. Rather, the movement direction of the hip modulated the reflex responses local to the joint. The patellar tendon reflex amplitude was larger when the perturbation was delivered during hip extension compared with hip flexion. The response to Achilles vibration was modulated by hip movement, with an increased tonic component during hip flexion compared with extension. These results demonstrate that hip-mediated sensory signals modulate activity in distal muscles of the leg and appear to play a unique role in modulation of spastic muscle activity throughout the leg in SCI.

  14. The relationship of leg volume and leg mass with anaerobic performance and knee strength in wrestlers

    Directory of Open Access Journals (Sweden)

    Erdal Zorba

    2010-01-01

    Full Text Available The purpose of the present study was to determination of the relationship between leg volume, leg mass with anaerobic performance and knee strength in wrestlers. 31 wrestlers from a university students participated in this study voluntarily (X age: 21.09 ± 0.99 yrs. Circumferential measurement were used for the determination of leg volume by Frustum Method and after that, a regression formula was used. For this formulas, while the R square (R2 value was .95 and the standart error value was .056. Leg mass was determined by the Hanavan Method. Wingate Anaerobic Power Test (WAnT was used for the determination of anaerobic performance and Isometric Knee Dynamometer was used for the determination of knee strength. Results of Pearson Product Moment correlation analysis, leg volume was significantly correlated with leg mass (r=.993; pnee strength was found to be correlated with anaerobic performance.

  15. Suprachiasmatic vasopressin and the circadian regulation of voluntary locomotor behavior.

    Science.gov (United States)

    Cormier, Holly C; Della-Maggiore, Valeria; Karatsoreos, Ilia N; Koletar, Margaret M; Ralph, Martin R

    2015-01-01

    A role for arginine vasopressin in the circadian regulation of voluntary locomotor behavior (wheel running activity) was investigated in the golden hamster, Mesocricetus auratus. Spontaneous nocturnal running was suppressed in a dose-dependent manner by systemic injections of vasopressin, and also in a concentration-dependent manner by microinjections directly into the hypothalamic suprachiasmatic nucleus. Pre-injections of a vasopressin V1 receptor antagonist into the nucleus reduced the suppression of behavior by vasopressin. Ethogram analyses revealed that peripheral drug injections predominantly increased grooming, flank marking, and sleep-related behaviors. Central injections did not induce sleep, but increased grooming and periods of 'quiet vigilance' (awake but not moving). Nocturnal behavioral profiles following either peripheral or central injections were similar to those shown by untreated animals in the hour prior to the onset of nocturnal wheel running. Site control vasopressin injections into the medial preoptic area or periaqueductal gray increased flank marking and grooming, but had no significant effect on locomotion, suggesting behavioral specificity of a vasopressin target near the suprachiasmatic nucleus. Both peripheral and central administration increased FOS-like immunoreactivity in the retinorecipient core of the suprachiasmatic nucleus. The distribution of FOS-positive cells overlapped the calbindin subregion, but was more extensive, and most calbindin-positive cells did not co-express FOS. We propose a model of temporal behavioral regulation wherein voluntary behavior, such as nocturnal locomotor activity, is inhibited by the activity of neurons in the suprachiasmatic ventrolateral core that project to the posterior hypothalamus and are driven by rhythmic vasopressin input from the dorsomedial shell.

  16. Clinical quality indicators of venous leg ulcers

    DEFF Research Database (Denmark)

    Kjaer, Monica L; Mainz, Jan; Soernsen, Lars T

    2005-01-01

    In the clinical setting, diagnosis and treatment of venous leg ulcers can vary considerably from patient to patient. The first step to reducing this variation is to document venous leg ulcer care through use of quantitative scientific documentation principles. This requires the development of valid...... and reliable evidence-based quality indicators of venous leg ulcer care. A Scandinavian multidisciplinary, cross-sectional panel of wound healing experts developed clinical quality indicators on the basis of scientific evidence from the literature and subsequent group nominal consensus of the panel......; an independent medical doctor tested the feasibility and reliability of these clinical indicators, assessing the quality of medical technical care on 100 consecutive venous leg ulcer patients. Main outcome measures were healing, recurrence, pain, venous disease diagnosis, differential diagnosis and treatment...

  17. Poison ivy on the leg (image)

    Science.gov (United States)

    This is a typical early appearance of a poison ivy rash, located on the leg. These early lesions ... line where the skin has brushed against the poison ivy plant. The rash is caused by skin contact ...

  18. Support Leg Loading in Punt Kicking

    Science.gov (United States)

    Kermond, John; Konz, Stephen

    1978-01-01

    Maximum distance in football punt kicking is associated with a maximum force transfer to the ball rather than a maximum force transfer through the ground via the support leg. For maximum distance, tred lightly. (Author)

  19. Leg or foot amputation - dressing change

    Science.gov (United States)

    ... gov/ency/patientinstructions/000018.htm Leg or foot amputation - dressing change To use the sharing features on ... guideline for management for rehabilitation of lower limb amputation. January 2008. www.healthquality.va.gov/guidelines/Rehab/ ...

  20. Wing and body motion and aerodynamic and leg forces during take-off in droneflies.

    Science.gov (United States)

    Chen, Mao Wei; Zhang, Yan Lai; Sun, Mao

    2013-12-06

    Here, we present a detailed analysis of the take-off mechanics in droneflies performing voluntary take-offs. Wing and body kinematics of the insects during take-off were measured using high-speed video techniques. Based on the measured data, the inertia force acting on the insect was computed and the aerodynamic force of the wings was calculated by the method of computational fluid dynamics. Subtracting the aerodynamic force and the weight from the inertia force gave the leg force. In take-off, a dronefly increases its stroke amplitude gradually in the first 10-14 wingbeats and becomes airborne at about the 12th wingbeat. The aerodynamic force increases monotonously from zero to a value a little larger than its weight, and the leg force decreases monotonously from a value equal to its weight to zero, showing that the droneflies do not jump and only use aerodynamic force of flapping wings to lift themselves into the air. Compared with take-offs in insects in previous studies, in which a very large force (5-10 times of the weight) generated either by jumping legs (locusts, milkweed bugs and fruit flies) or by the 'fling' mechanism of the wing pair (butterflies) is used in a short time, the take-off in the droneflies is relatively slow but smoother.

  1. Microgravity, Mesh-Crawling Legged Robots

    Science.gov (United States)

    Behar, Alberto; Marzwell, Neville; Matthews, Jaret; Richardson, Krandalyn; Wall, Jonathan; Poole, Michael; Foor, David; Rodgers, Damian

    2008-01-01

    The design, fabrication, and microgravity flight-testing are part of a continuing development of palm-sized mobile robots that resemble spiders (except that they have six legs apiece, whereas a spider has eight legs). Denoted SpiderBots (see figure), they are prototypes of proposed product line of relatively inexpensive walking robots that could be deployed in large numbers to function cooperatively in construction, repair, exploration, search, and rescue activities in connection with exploration of outer space and remote planets.

  2. Win-stay-lose-learn promotes cooperation in the prisoner’s dilemma game with voluntary participation

    Science.gov (United States)

    Chu, Chen; Liu, Jinzhuo; Shen, Chen; Jin, Jiahua; Shi, Lei

    2017-01-01

    Voluntary participation, demonstrated to be a simple yet effective mechanism to promote persistent cooperative behavior, has been extensively studied. It has also been verified that the aspiration-based win-stay-lose-learn strategy updating rule promotes the evolution of cooperation. Inspired by this well-known fact, we combine the Win-Stay-Lose-Learn updating rule with voluntary participation: Players maintain their strategies when they are satisfied, or players attempt to imitate the strategy of one randomly chosen neighbor. We find that this mechanism maintains persistent cooperative behavior, even further promotes the evolution of cooperation under certain conditions. PMID:28182707

  3. Three cross leg flaps for lower leg reconstruction of Gustilo type III C open fracture

    Directory of Open Access Journals (Sweden)

    Kazufumi Sano

    2016-01-01

    Full Text Available A 60 year old male had Gustilo type III C open fracture of the right lower leg. After radical debridement, the large open defect including certain loss of the bone tissue was successfully augmented and covered, by consecutive three cross-leg flaps, which consisted of the free rectus abdominis musculocutaneous flap, the fibula osteocutaneous flap and the conventional sural flap. Although indication for amputation or preservation is decided with multiple factors in each case, a strategic combination of cross-leg flap, free flap, external fixation and vascular delay could increase the potential of preservation of the lower leg with even disastrous Gustilo type III C.

  4. Passive legged, multi-segmented, robotic vehicle.

    Energy Technology Data Exchange (ETDEWEB)

    Hayward, David R.

    2003-11-01

    The Passive-legged, Multi-segmented, Robotic Vehicle concept is a simple legged vehicle that is modular and scaleable, and can be sized to fit through confined areas that are slightly larger than the size of the vehicle. A specific goal of this project was to be able to fit through the opening in the fabric of a chain link fence. This terrain agile robotic platform will be composed of multiple segments that are each equipped with appendages (legs) that resemble oars extending from a boat. Motion is achieved by pushing with these legs that can also flex to fold next to the body when passing through a constricted area. Each segment is attached to another segment using an actuated joint. This joint represents the only actuation required for mobility. The major feature of this type of mobility is that the terrain agility advantage of legs can be attained without the complexity of the multiple-actuation normally required for the many joints of an active leg. The minimum number of segments is two, but some concepts require three or more segments. This report discusses several concepts for achieving this type of mobility, their design, and the results obtained for each.

  5. Fast unilateral isometric knee extension torque development and bilateral jump height.

    Science.gov (United States)

    de Ruiter, Cornelis J; Van Leeuwen, Daniel; Heijblom, Arjan; Bobbert, Maarten F; de Haan, Arnold

    2006-10-01

    We hypothesized that the initial rate (first 40 ms) of unilateral knee extensor torque development during a maximally fast isometric contraction would depend on the subjects' ability for fast neural activation and that it would predict bilateral jumping performance. Nine males (21.8 +/- 0.9 yr, means +/- SD) performed unilateral fast isometric knee extensions (120 degrees knee angle) without countermovement on a dynamometer and bilateral squat jumps (SJ) and countermovement jumps (CMJ) starting from 90 and 120 degrees knee angles (full extension = 180 degrees ). The dynamometer contractions started either from full relaxation or from an isometric pre-tension (15% maximal isometric torque, Tmax). Torque time integral for the first 40 ms after torque onset (TTI-40, normalized to Tmax) and averaged normalized rectified knee extensor EMG for 40 ms before fast torque onset (EMG-40) were used to quantify initial torque rise and voluntary muscle activation. TTI-40 without pre-tension (range: 0.02-0.19% Tmax per second) was significantly lower than TTI-40 with pre-tension, and both were significantly (r = 0.81 and 0.80) related to EMG-40. During jumping, similar significant positive relations were found between jump height and knee extensor EMG during the first 100 ms of the rise in ground reaction force. There also were significant positive linear relations between dynamometer TTI-40 and jump height (r = 0.75 (SJ 90), 0.84 (SJ 120), 0.76 (CMJ 90), and 0.86 (CMJ 120)) but not between dynamometer Tmax and jump height (-0.16 < r < 0.02). One-legged TTI-40 to a large extent explained the variation in jump height. The ability to produce a high efferent neural drive before muscle contraction seemed to dominate performance in both the simple single-joint isometric task and the complex multijoint dynamic task.

  6. The parallel programming of voluntary and reflexive saccades.

    Science.gov (United States)

    Walker, Robin; McSorley, Eugene

    2006-06-01

    A novel two-step paradigm was used to investigate the parallel programming of consecutive, stimulus-elicited ('reflexive') and endogenous ('voluntary') saccades. The mean latency of voluntary saccades, made following the first reflexive saccades in two-step conditions, was significantly reduced compared to that of voluntary saccades made in the single-step control trials. The latency of the first reflexive saccades was modulated by the requirement to make a second saccade: first saccade latency increased when a second voluntary saccade was required in the opposite direction to the first saccade, and decreased when a second saccade was required in the same direction as the first reflexive saccade. A second experiment confirmed the basic effect and also showed that a second reflexive saccade may be programmed in parallel with a first voluntary saccade. The results support the view that voluntary and reflexive saccades can be programmed in parallel on a common motor map.

  7. Voluntary energy optimisation - Taking responsibility; Verantwortungsvoll

    Energy Technology Data Exchange (ETDEWEB)

    Baettig, I.

    2006-07-01

    This interview with Konrad Kyburz, CEO of a printing shop in Dielsdorf, Switzerland, discusses how energy consumption can be reduced on a voluntary basis. The provision free-of-charge of heat recovered from the drying ovens of the printing presses to a nearby sports facility is discussed. The realisation of an energy consumption analysis and the resulting increases in the efficiency of energy usage in the printing facility are discussed. Further improvements such as the use of variable-frequency compressor drives and heating with natural gas that helped in making energy savings of well over 15% are discussed.

  8. Voluntary participation and cooperation in a collective-good game.

    OpenAIRE

    Kene Boun My; Benoît Chalvignac

    2009-01-01

    We study the effect of voluntary participation in the context of a collective-good experiment. We investigate whether the freedom to participate in the game or not increases contribution levels and enhances their evolution. The analysis of two voluntary participation treatments supports a positive effect of an attractive exit option on both contribution levels and their sustainability. We conclude that the voluntary contribution mechanism can provide sustainable cooperation levels and that th...

  9. Reversal of optic neuropathy secondary to voluntary globe luxation.

    Science.gov (United States)

    Yaman, Aylin; Ozturk, Taylan; Soylev, Meltem F

    2009-04-01

    Luxation of the globe is rare in the general population and may be spontaneous, voluntary, or traumatic. Spontaneous or voluntary globe luxation results from shallow orbit, floppy eyelids, lax orbital ligaments, backward displacement of orbital septum, or proptotic eyes due to orbital tumors or infiltrative processes, as in Grave's ophthalmopathy. The authors report a case with unilateral voluntary globe luxation presented with unilateral progressive visual loss.

  10. Current State of the Voluntary Renewable Energy Market (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Heeter, J.

    2013-09-01

    This presentation highlights the status of the voluntary green power market in 2012. The voluntary green power market totaled more than 48 million MWh in 2012, with about 1.9 million customers participating. The supply continues to be dominated by wind, though solar is increasing its share of utility green pricing programs. Prices for voluntary renewable energy certificates (RECs) increased to above $1/MWh.

  11. Genetic parameters for claw and leg health, foot and leg conformation, and locomotion in Danish Holsteins

    DEFF Research Database (Denmark)

    Laursen, M. V.; Boelling, D.; Mark, Thomas

    2009-01-01

    The purpose of this study was to estimate the genetic correlations among claw and leg health and potential indicator traits. Claw health was defined as absence of heel horn erosion, interdigital dermatitis, interdigital phlegmon, interdigital hyperplasia, laminitis, and sole ulcer. Leg health...

  12. The effect of gender on force, muscle activity, and frontal plane knee alignment during maximum eccentric leg-press exercise.

    Science.gov (United States)

    Liebensteiner, Michael C; Platzer, Hans-Peter; Burtscher, Martin; Hanser, Friedrich; Raschner, Christian

    2012-03-01

    To investigate for gender differences during eccentric leg-press exercise. Tears of the anterior cruciate ligament (ACL) are considered to be related to eccentric tasks, altered neuromuscular control (e.g., reduced co-contraction of hamstrings), and increased knee abduction (valgus alignment). Based on these observations and the fact that ACL tears are more common in women, it was hypothesized that men and women differ significantly with regard to key parameters of force, knee stabilization, and muscle activity when exposed to maximum eccentric leg extension. Thirteen women and thirteen men were matched for age and physical activity. They performed maximum isokinetic eccentric leg-pressing against footplates of varied stability. The latter was done because earlier studies had shown that perturbational test conditions might be relevant in respect of ACL injuries. Key parameters of force, frontal plane knee stabilization, and muscle recruitment of significant muscles crossing the knee were recorded. The 'force stabilization deficit' (difference between maximum forces under normal and perturbed leg-pressing) did not differ significantly between genders. Likewise, parameters of muscle activity and frontal plane leg stabilization revealed no significant differences between men and women. This study is novel, in that gender differences in parameters of force, muscle activity, and leg kinematic were investigated during functional conditions of eccentric leg-pressing. No gender differences were observed in the measured parameters. However, the conclusion should be viewed with caution because the findings concurred with, but also contrasted, previous research in this field. Diagnostic study, Level III.

  13. Quantifying thigh muscle co-activation during isometric knee extension contractions: within- and between-session reliability.

    Science.gov (United States)

    Katsavelis, Dimitrios; Threlkeld, A Joseph

    2014-08-01

    Muscle co-activation around the knee is important during ambulation and balance. The wide range of methodological approaches for the quantification of co-activation index (CI) makes comparisons across studies and populations difficult. The present study determined within- and between-session reliability of different methodological approaches for the quantification of the CI of the knee extensor and flexor muscles during maximum voluntary isometric contractions (MVICs). Eight healthy volunteers participated in two repeated testing sessions. A series of knee extension MVICs of the dominant leg with concomitant torque and electromyographic (EMG) recordings were captured. CI was calculated utilizing different analytical approaches. Intraclass correlation coefficient (ICC) showed that within-session measures displayed higher reliability (ICC>0.861) and lower variability (Coefficient of variation; CV24.2%). A selection of a 500ms or larger window of RMS EMG activity around the PT delivered more reliable and less variable results than other approaches. Our findings suggest that the CI can provide a reliable measure for comparisons among conditions and is best utilized for within-session experimental designs.

  14. Modelling the maximum voluntary joint torque/angular velocity relationship in human movement.

    Science.gov (United States)

    Yeadon, Maurice R; King, Mark A; Wilson, Cassie

    2006-01-01

    The force exerted by a muscle is a function of the activation level and the maximum (tetanic) muscle force. In "maximum" voluntary knee extensions muscle activation is lower for eccentric muscle velocities than for concentric velocities. The aim of this study was to model this "differential activation" in order to calculate the maximum voluntary knee extensor torque as a function of knee angular velocity. Torque data were collected on two subjects during maximal eccentric-concentric knee extensions using an isovelocity dynamometer with crank angular velocities ranging from 50 to 450 degrees s(-1). The theoretical tetanic torque/angular velocity relationship was modelled using a four parameter function comprising two rectangular hyperbolas while the activation/angular velocity relationship was modelled using a three parameter function that rose from submaximal activation for eccentric velocities to full activation for high concentric velocities. The product of these two functions gave a seven parameter function which was fitted to the joint torque/angular velocity data, giving unbiased root mean square differences of 1.9% and 3.3% of the maximum torques achieved. Differential activation accounts for the non-hyperbolic behaviour of the torque/angular velocity data for low concentric velocities. The maximum voluntary knee extensor torque that can be exerted may be modelled accurately as the product of functions defining the maximum torque and the maximum voluntary activation level. Failure to include differential activation considerations when modelling maximal movements will lead to errors in the estimation of joint torque in the eccentric phase and low velocity concentric phase.

  15. One-legged endurance training: leg blood flow and oxygen extraction during cycling exercise

    DEFF Research Database (Denmark)

    Rud, B; Foss, O; Krustrup, Peter

    2012-01-01

    Aim: As a consequence of enhanced local vascular conductance, perfusion of muscles increases with exercise intensity to suffice the oxygen demand. However, when maximal oxygen uptake (VO(2) max) and cardiac output are approached, the increase in conductance is blunted. Endurance training increases...... muscle metabolic capacity, but to what extent that affects the regulation of muscle vascular conductance during exercise is unknown. Methods: Seven weeks of one-legged endurance training was carried out by twelve subjects. Pulmonary VO(2) during cycling and one-legged cycling was tested before and after...... training, while VO(2) of the trained leg (TL) and control leg (CL) during cycling was determined after training. Results: VO(2) max for cycling was unaffected by training, although one-legged VO(2) max became 6.7 (2.3)% (mean ± SE) larger with TL than with CL. Also TL citrate synthase activity was higher...

  16. Effect of induced leg muscle fatigue on exertional dyspnea in healthy subjects.

    Science.gov (United States)

    Sharma, Pramod; Morris, Norman R; Adams, Lewis

    2015-01-01

    The genesis of dyspnea is complex. It appears to be related to central respiratory drive although prevailing leg fatigue could independently potentiate dyspnea. We hypothesized that experimentally induced leg fatigue generates more intense exertional dyspnea for a given level of ventilatory drive. Following familiarization, 19 healthy subjects (32.2 ± 7.6 yr; 11 men) performed a 5-min treadmill test (speed: ∼4 km/h; grade: ∼25%) on two separate days randomized between control (C) and experimentally induced leg fatigue (E) achieved by repeated knee extension against 40% body weight until task failure. Oxygen uptake (V̇o2, l/min), carbon dioxide output (V̇co2, l/min), ventilation (V̇e, l/min), and respiratory rate (fR) were measured breath by breath. Heart rate (HR) and perceived dyspnea intensity (0-10 numerical scale) were recorded continuously. Data were averaged over 30-s intervals. Exertional dyspnea during E was statistically significantly higher (E vs. C: 4.2 ± 0.2 vs. 3.4 ± 0.2, P leg fatigue. These findings support the hypothesis that the intensity of exertional dyspnea is exacerbated by peripheral afferent information from fatigued leg muscles.

  17. [Contralateral replantation after bilateral traumatic lower leg amputation. Case report with 6 year follow-up].

    Science.gov (United States)

    Betz, A; Stock, W; Hierner, R; Sebisch, E; Schweiberer, L

    1995-05-01

    A 66-year-old patient attempted suicide by jumping in front of a train. The lower extremities were amputated at different levels. On the right side, there was a complete amputation within the distal third of the lower leg. Proximal to the amputation site, there was an extensive soft-tissue and bone defect. On the left side, there was a crush injury of the tarsal and mid-tarsal bones. The left lower leg showed only few injuries. An ipsilateral (anatomical) replantation was not possible. In order to save one lower extremity, we decided to carry out a cross-over (contralateral) replantation of the right foot to the left lower leg. After a follow-up of six years, the patient is able to walk well with her prosthesis on the right side and the right foot hooked up to the left lower leg. Functionally, this treatment (cross-over replantation-one-side prosthesis of the lower leg) is much better than the prosthesis on both extremities, as the result has shown. Also from a psychological point of view, it seems to be better for the patient to preserve one extremity even with a cross-over replanted foot.

  18. Association between Thigh Muscle Volume and Leg Muscle Power in Older Women.

    Directory of Open Access Journals (Sweden)

    Ulrich Lindemann

    Full Text Available The construct of sarcopenia is still discussed with regard to best appropriate measures of muscle volume and muscle function. The aim of this post-hoc analysis of a cross-sectional experimental study was to investigate and describe the hierarchy of the association between thigh muscle volume and measurements of functional performance in older women. Thigh muscle volume of 68 independently living older women (mean age 77.6 years was measured via magnetic resonance imaging. Isometric strength was assessed for leg extension in a movement laboratory in sitting position with the knee flexed at 90° and for hand grip. Maximum and habitual gait speed was measured on an electronic walk way. Leg muscle power was measured during single leg push and during sit-to-stand performance. Thigh muscle volume was associated with sit-to-stand performance power (r = 0.628, leg push power (r = 0.550, isometric quadriceps strength (r = 0.442, hand grip strength (r = 0.367, fast gait speed (r = 0.291, habitual gait speed (r = 0.256, body mass index (r = 0.411 and age (r = -0.392. Muscle power showed the highest association with thigh muscle volume in healthy older women. Sit-to-stand performance power showed an even higher association with thigh muscle volume compared to single leg push power.

  19. Association between Thigh Muscle Volume and Leg Muscle Power in Older Women.

    Science.gov (United States)

    Lindemann, Ulrich; Mohr, Christian; Machann, Juergen; Blatzonis, Konstantinos; Rapp, Kilian; Becker, Clemens

    2016-01-01

    The construct of sarcopenia is still discussed with regard to best appropriate measures of muscle volume and muscle function. The aim of this post-hoc analysis of a cross-sectional experimental study was to investigate and describe the hierarchy of the association between thigh muscle volume and measurements of functional performance in older women. Thigh muscle volume of 68 independently living older women (mean age 77.6 years) was measured via magnetic resonance imaging. Isometric strength was assessed for leg extension in a movement laboratory in sitting position with the knee flexed at 90° and for hand grip. Maximum and habitual gait speed was measured on an electronic walk way. Leg muscle power was measured during single leg push and during sit-to-stand performance. Thigh muscle volume was associated with sit-to-stand performance power (r = 0.628), leg push power (r = 0.550), isometric quadriceps strength (r = 0.442), hand grip strength (r = 0.367), fast gait speed (r = 0.291), habitual gait speed (r = 0.256), body mass index (r = 0.411) and age (r = -0.392). Muscle power showed the highest association with thigh muscle volume in healthy older women. Sit-to-stand performance power showed an even higher association with thigh muscle volume compared to single leg push power.

  20. Voluntary self-touch increases body ownership

    Directory of Open Access Journals (Sweden)

    Masayuki eHara

    2015-10-01

    Full Text Available Experimental manipulations of body ownership have indicated that multisensory integration is central to forming bodily self-representation. Voluntary self-touch is a unique multisensory situation involving corresponding motor, tactile and proprioceptive signals. Yet, even though self-touch is frequent in everyday life, its contribution to the formation of body ownership is not well understood. Here we investigated the role of voluntary self-touch in body ownership using a novel adaptation of the rubber hand illusion (RHI, in which a robotic system and virtual reality allowed participants self-touch of real and virtual hands. In the first experiment, active and passive self-touch were applied in the absence of visual feedback. In the second experiment, we tested the role of visual feedback in this bodily illusion. Finally, in the third experiment, we compared active and passive self-touch to the classical RHI in which the touch is administered by the experimenter. We hypothesized that active self-touch would increase ownership over the virtual hand through the addition of motor signals strengthening the bodily illusion. The results indicated that active self-touch elicited stronger illusory ownership compared to passive self-touch and sensory only stimulation, and indicate an important role of active self-touch in the formation of bodily self.

  1. Evaluation of the information and support services in the voluntary sector using a new P-C-P (pivotal-core-peripheral) attributes model.

    Science.gov (United States)

    Philip, G; Stewart, J

    2000-11-01

    This paper describes the development and use of a modified SERVQUAL research instrument for measuring the service quality of voluntary organizations from the perspective of their 'customers'. A series of focus group meetings were run with providers and users of the services to identify the appropriate dimensions of service quality. These were structured meetings led by the researchers addressing set questions in a group setting. The meeting enabled the identification of six different dimensions of service quality which neatly mapped on to the pivotal-core-peripheral (P-C-P attributes model [Philip and Hazlett, 1997]), which was developed after extensive research of existing models such as SERVQUAL. These dimensions were used to develop a questionnaire to assess service quality within the voluntary sector. The questionnaire was distributed to 2005 service users, representing eight voluntary organizations from across Northern Ireland. The research resulted in the development of a methodology and research instrument suitable for measuring service quality in the voluntary sector.

  2. Functional recovery following manipulation of muscles and sense organs in the stick insect leg.

    Science.gov (United States)

    Bässler, Ulrich; Wolf, Harald; Stein, Wolfgang

    2007-11-01

    We studied functional recovery of leg posture and walking behaviour in the femur-tibia joint control system of stick insects. Leg extensions in resting animals and during walking are produced by different parts of a single extensor muscle. (a) Ablation of the muscle part responsible for fast movements prevented leg extension during the swing phase. Resting posture remained unaffected. Within a few post-operative days, extension movements recovered, provided that sensory feedback was available. Extension movements were now driven by the muscle part which in intact animals controls the resting posture only. (b) Selective ablation of this (slow) muscle part affected the resting posture, while walking was unaffected. The resting posture partly recovered during subsequent days. To test the range of functional recovery and underlying mechanisms, we additionally transected muscle motor innervation, or we inverted or ablated sensory feedback. We found that recovery was based on both muscular and neuronal mechanisms. The latter required appropriate sensory feedback for the process of recovery, but not for the maintenance of the recovered state. Our results thus indicate the existence of a sensory template that guides recovery. Recovery was limited to a behavioural range that occurs naturally in intact animals, though in different behavioural contexts.

  3. Kinematic control of extreme jump angles in the red leg running frog (Kassina maculata).

    Science.gov (United States)

    Richards, Christopher Thomas; Porro, Laura Beatriz; Collings, Amber Jade

    2017-03-08

    The kinematic flexibility of frog hindlimbs enables multiple locomotor modes within a single species. Prior work has extensively explored maximum performance capacity in frogs; however, the mechanisms by which anurans modulate performance within locomotor modes remain unclear. We explored how Kassina maculata, a species known for both running and jumping abilities, modulates takeoff angle from horizontal to nearly vertical. Specifically, how do 3D motions of leg segments coordinate to move the center of mass (COM) upwards and forwards? How do joint rotations modulate jump angle? High-speed video was used to quantify 3D joint angles and their respective rotation axis vectors. Inverse kinematics was used to determine how hip, knee and ankle rotations contribute to components of COM motion. Independent of takeoff angle, leg segment retraction (rearward rotation) was twofold greater than adduction (downward rotation). Additionally, the joint rotation axis vectors reoriented through time suggesting dynamic shifts in relative roles of joints. We found two hypothetical mechanisms for increasing takeoff angle: Firstly, greater knee and ankle excursion increased shank adduction, elevating the COM. Secondly, during the steepest jumps the body rotated rapidly backwards to redirect the COM velocity. This rotation was not caused by pelvic angle extension, but rather by kinematic transmission from leg segments via reorientation of the joint rotation axes. We propose that K. maculata uses proximal leg retraction as the principal kinematic drive while dynamically tuning jump trajectory by knee and ankle joint modulation.

  4. Dimensional synthesis of a leg mechanism

    Science.gov (United States)

    Pop, F.; Lovasz, E.-Ch; Pop, C.; Dolga, V.

    2016-08-01

    An eight bar leg mechanism dimensional synthesis is presented. The mathematical model regarding the synthesis is described and the results obtained after computation are verified with help of 2D mechanism simulation in Matlab. This mechanism, inspired from proposed solution of Theo Jansen, is integrated into the structure of a 2 DOF quadruped robot. With help of the kinematic synthesis method described, it is tried to determine new dimensions for the mechanism, based on a set of initial conditions. These are established by taking into account the movement of the end point of the leg mechanism, which enters in contact with the ground, during walking. An optimization process based on the results obtained can be conducted further in order to find a better solution for the leg mechanism.

  5. Dipoles on a Two-leg Ladder

    DEFF Research Database (Denmark)

    Gammelmark, Søren; Zinner, Nikolaj Thomas

    2013-01-01

    We study polar molecules with long-range dipole-dipole interactions confined to move on a two-leg ladder for different orientations of the molecular dipole moments with respect to the ladder. Matrix product states are employed to calculate the many-body ground state of the system as function...... of lattice filling fractions, perpendicular hopping between the legs, and dipole interaction strength. We show that the system exhibits zig-zag ordering when the dipolar interactions are predominantly repulsive. As a function of dipole moment orientation with respect to the ladder, we find...... that there is a critical angle at which ordering disappears. This angle is slightly larger than the angle at which the dipoles are non-interacting along a single leg. This behavior should be observable using current experimental techniques....

  6. AN EFFECTIVE HUMAN LEG MODELING METHOD

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Digital medicine is a new concept in medical field, and the need for digital human body is increasing these years. This paper used Free Form Deformation (FFD) to model the motion of human leg. It presented the motion equations of knee joint on the basis of anatomic structure and motion characters, then transmitted the deformation to the mesh of leg through a simplified FFD that only used two-order B-spline basis function. The experiments prove that this method can simulate the bend of leg and the deformation of muscles fairly well. Compared with the method of curved patches, this method is more convenient and effective. Further more, those equations can be easily applied to other joint models of human body.

  7. Leg Spasticity and Ambulation in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Swathi Balantrapu

    2014-01-01

    Full Text Available Background. Spasticity of the legs is common in multiple sclerosis (MS, but there has been limited research examining its association with ambulatory outcomes. Objective. This study examined spasticity of the legs and its association with multiple measures of ambulation in persons with MS. Methods. The sample included 84 patients with MS. Spasticity of the legs was measured using a 5-point rating scale ranging between 0 (normal and 4 (contracted. Patients completed the 6-minute walk (6 MW, timed 25 foot walk (T25FW, and timed up-and-go (TUG, and O2 cost of walking was measured during the 6 MW. The patients undertook two walking trials on a GAITRite (CIR systems, Inc. for measuring spatial and temporal parameters of gait. The patients completed the Multiple Sclerosis Walking Scale-12 (MSWS-12 and wore an accelerometer over a seven-day period. Results. 52% (n=44 of the sample presented with spasticity of the legs. Those with leg spasticity had significantly worse ambulation as measured by 6 MW (P=0.0001, d=-0.86, T25FW (P=0.003,d=0.72, TUG (P=0.001, d=0.84, MSWS-12 (P=0.0001,d=1.09, O2 cost of walking (P=0.001, d=0.75, average steps/day (P<0.05, d=-0.45, and walking velocity (P<0.05, d=-0.53 and cadence (P<0.05, d=-0.46. Conclusion. Leg spasticity was associated with impairments in ambulation, including alterations in spatiotemporal parameters and free-living walking.

  8. Six weeks' aerobic retraining after two weeks' immobilization restores leg lean mass and aerobic capacity but does not fully rehabilitate leg strenght in young and older men

    DEFF Research Database (Denmark)

    Vigelsø Hansen, Andreas; Gram, Martin; Wiuff, Caroline

    2015-01-01

    OBJECTIVE: To determine the effect of aerobic retraining as rehabilitation after short-term leg immobilization on leg strength, leg work capacity, leg lean mass, leg muscle fibre type composition and leg capillary supply, in young and older men. SUBJECTS AND DESIGN: Seventeen young (23 ± 1 years)...

  9. Radioprotection by WR-151327 against the late normal tissue damage in mouse hind legs from gamma ray radiation

    Energy Technology Data Exchange (ETDEWEB)

    Matsushita, Satoru; Ando, Koichi; Koike, Sachiko [National Institute of Radiological Sciences, Chiba (Japan)] [and others

    1994-11-15

    To evaluate the protective effect of WR-151327 on late radiation-induced damaged to normal tissues in mice, the right hind legs of mice with or without WR-151327 administration (400 mg/kg) were irradiated with {sup 137}Cs gamma rays. Leg contracture and skin shrinkage assays were performed at 380 days after irradiation. The mice were killed on day 400 postirradiation and histological sections of the legs were made. The thickness of the dermis, epidermis, and skin (dermis plus epidermis) was measured. The muscular area of the legs and the posterior knee angle between the femur and tibia were also measured. The left hind legs were similarly assessed as nonirradiated controls. Group means and standard deviations were calculated and dose-response curves were drawn for every endpoint. Then, the dose modifying factor (DMF) for each endpoint and the correlations among endpoints were determined. Latae damage assayed by leg contracture and skin shrinkage progressed with increasing radiation dose. However, it was reduced by drug treatment. The significant effect was indicated for skin shrinkage by a DMF of 1.8 at 35%. The DMF for leg contracture was 1.3 at 6 mm. In the irradiated legs, epidermal hyperplasia and dermal fibrosis in the skin, muscular atrophy, and extension disturbance of the knee joint were observed. These changes progressed with increasing radiation dose. Skin damage assayed by the present endpoints was also reduced by drug treatment by DMFs of 1.4 to 1.7. However, DMFs for damage to the muscle and knee were not determined because no isoeffect was observed. There were good correlations between leg contracture or skin shrinkage and the other endpoints in both untreated and drug-treated mice. WR-151327 has the potential to protect against radiation-induced late normal tissue damage. 17 refs., 6 figs., 2 tabs.

  10. The Molecular Genetics of Restless Legs Syndrome.

    Science.gov (United States)

    Rye, David B

    2015-09-01

    Restless legs syndrome (RLS) is a common sensorimotor trait defined by symptoms that interfere with sleep onset and maintenance in a clinically meaningful way. Nonvolitional myoclonus while awake and asleep is a sign of the disorder and an informative endophenotype. The genetic contributions to RLS/periodic leg movements are substantial, are among the most robust defined to date for a common disease, and account for much of the variance in disease expressivity. The disorder is polygenic, as revealed by recent genome-wide association studies. Experimental studies are revealing mechanistic details of how these common variants might influence RLS expressivity.

  11. The mysteries of restless legs syndrome.

    Science.gov (United States)

    Martin, Caren McHenry

    2007-11-01

    Restless legs syndrome (RLS) is a sensorimotor disorder characterized by the uncontrollable urge to move the legs. This urge can often be accompanied by pain or other unpleasant sensations, and it either occurs or worsens with rest. Affecting an estimated 6% to 15% of the adult population, RLS compromises the patient's ability to sleep and can significantly decrease quality of life. Because diagnosis currently relies solely on patient (or caregiver) interview, recognizing the symptoms of RLS and knowing what medications treat this condition--as well as the many that exacerbate it--is important for all health care practitioners.

  12. Review of periodic limb movement and restless leg syndrome

    Directory of Open Access Journals (Sweden)

    Natarajan R

    2010-01-01

    Full Text Available Periodic limb movement (PLM and Restless leg syndrome (RLS are types of sleep disorders that are not very well recognized in clinical practice. While RLS is a clinical diagnosis, the diagnosis of PLM is made by polysomnography. They share the same pathophysiology and often respond to the same treatment. To date all the epidemiological studies have reported the prevalence between 2% and 15%. It has recently become known that mild obstructive sleep apnea and upper airway resistance syndrome (UARS can masquerade as PLM syndrome. New discoveries have been made with regard to genetics and PLM and RLS. Detailed review on this subject should improve the awareness of these disorders, both among general physicians and specialists. Extensive review of journals in the past 20 years was made using Medline search.

  13. 5 CFR 831.405 - Interest on voluntary contributions.

    Science.gov (United States)

    2010-01-01

    ....405 Section 831.405 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE... contributions stop earning interest on the earliest of— (1) The date when OPM authorizes payment to the... voluntary contributions to purchase additional annuity, voluntary contributions stop earning interest on...

  14. Efficiency of voluntary closing hand and hook prostheses

    NARCIS (Netherlands)

    Smit, G.; Plettenburg, D.H.

    2010-01-01

    The Delft Institute of Prosthetics and Orthotics has started a research program to develop an improved voluntary closing, body-powered hand prosthesis. Five commercially available voluntary closing terminal devices were mechanically tested: three hands [Hosmer APRL VC hand, Hosmer Soft VC Male hand,

  15. Voluntary and involuntary adaptation of gait in Parkinson's disease

    NARCIS (Netherlands)

    Zijlstra, W; Rutgers, AWF; Van Weerden, TW

    1998-01-01

    Voluntary and involuntary adaptation of gait in Parkinson's disease (PD) were studied in two separate experiments. In the first experiment, effects of changes in voluntary control were studied by asking PD patients and age-matched healthy subjects to adapt their walking pattern to visual cues result

  16. Re-Examining the Relationship between Age and Voluntary Turnover

    Science.gov (United States)

    Ng, Thomas W. H.; Feldman, Daniel C.

    2009-01-01

    In their quantitative review of the literature, Healy, Lehman, and McDaniel [Healy, M. C., Lehman, M., & McDaniel, M. A. (1995). Age and voluntary turnover: A quantitative review. "Personnel Psychology, 48", 335-345] concluded that age is only weakly related to voluntary turnover (average r = -0.08). However, with the significant changes in…

  17. Conditioning Bottlenose Dolphins (Tursiops Truncatus Gilli) for Voluntary Diving Studies

    Science.gov (United States)

    1992-12-31

    heartrate (EKG) to validate "voluntary" nature of dive EXAMINE ACTIVE DIVING CONDITIONS (open Ocean Mewwmenr) dive profiles using TDR respiration... heartrate electrodes Open Ocean Experiments ’wear instrument package (TDR) perform voluntary dive up to 200 meters readily present tail flukes for

  18. Students' vocational choices and voluntary action: A 12-nation study

    NARCIS (Netherlands)

    D. Haski-Leventhal (Debbie); R.A. Cnaan (Ram); F. Handy (Femida); J.L. Brudney (Jeffrey); K. Holmes (Kirsten); L. Hustinx (Lesley); C. Kang (Chulhee); M. Kassam (Meenaz); L.C.P.M. Meijs (Lucas); B. Ranade (Bhagyashree); N. Yamauchi (Naoto); A.B. Yeung (Anne Birgitta); S. Zrinscak (Sinisa)

    2008-01-01

    textabstractPrevious research on student involvement suggested that business and engineering students manifest lowest rates of voluntary action. Similarly, it was thought that social science students are the most involved in voluntary action, with students of natural sciences and humanities in the m

  19. Integrating Voluntary Simplicity of Lifestyle into Home Economics.

    Science.gov (United States)

    Pestle, Ruth E.

    This curriculum guide presents guidelines for teaching concepts of Voluntary Simplicity in home economics in Florida. (Voluntary Simplicity is a lifestyle in which individuals choose to live more simply, considering the limited nature of the world's resources.) It is designed for use as a separate unit within different subject matter areas or as…

  20. 5 CFR 831.406 - Withdrawal of voluntary contributions.

    Science.gov (United States)

    2010-01-01

    ... precedence set forth in section 8342(c) of title 5, United States Code, is entitled to payment of the balance... contributions. (a) Before receiving additional annuity payments based on the voluntary contributions, a person who has made voluntary contributions may withdraw the balance while still an employee or Member,...

  1. 78 FR 54444 - Advisory Committee on Voluntary Foreign Aid Meeting

    Science.gov (United States)

    2013-09-04

    ...; ] AGENCY FOR INTERNATIONAL DEVELOPMENT Advisory Committee on Voluntary Foreign Aid Meeting AGENCY: United... Aid (ACVFA). Date: Wednesday, September 18, 2013. Time: 2:30 p.m. to 4:00 p.m. Location: Horizon Room..., Executive Director, Advisory Committee on Voluntary Foreign Aid (ACVFA), U.S. Agency for...

  2. 27 CFR 25.221 - Voluntary destruction of beer.

    Science.gov (United States)

    2010-04-01

    ... beer. 25.221 Section 25.221 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Voluntary Destruction § 25.221 Voluntary destruction of beer. (a) On brewery premises. (1) A brewer may destroy, at the brewery, beer on which the tax has...

  3. Assessment of the vibration on the foam legged and sheet metal-legged passenger seat

    Directory of Open Access Journals (Sweden)

    L. Dahil

    2015-10-01

    Full Text Available In this study, it was aim ed to decrease the vibration reaching to passenger from the legs of vehicle seats. In order to determine the levels of vibrations reaching at passengers, a test pad placed under the passenger seat was used, and HVM100 device was used for digitizing the information obtained. By transferring the vibration data to system by using HVM100 device, the acceleration graphics were prepared with Blaze software. As a result, it was determined that the acceleration values of seat legs made of foam material were lower than that of seat legs made of 2 mm thick sheet metal, so they damped the vibration better.

  4. Restless legs symptoms in a patient with above knee amputations: a case of phantom restless legs.

    Science.gov (United States)

    Hanna, Philip A; Kumar, Sanjeev; Walters, Arthur S

    2004-01-01

    We describe a 78-year-old gentleman who, following bilateral above-knee amputations, developed symptoms of restless legs syndrome in the absent portions of his lower extremities. These symptoms improved with dopamine agonist therapy. In addition, he later developed parkinsonism with prominent rest tremor on metoclopramide. This suggests that this individual had a dopamine-deficient state which predisposed him to both restless legs syndrome and drug-induced or drug-exacerbated parkinsonism. We propose expanding the spectrum of phantom limb phenomena to include phantom restless legs.

  5. Mechanics of cuticular elastic energy storage in leg joints lacking extensor muscles in arachnids.

    Science.gov (United States)

    Sensenig, Andrew T; Shultz, Jeffrey W

    2003-02-01

    Certain leg joints in arachnids lack extensor muscles and have elastically deformable transarticular sclerites spanning their arthrodial membranes, an arrangement consistent with a model in which flexor muscles load transarticular sclerites during flexion and energy from elastic recoil is used for extension. This study quantifies the potential contribution of elastic recoil to extension torque at joints of the fourth leg of representative arachnids. Extension torques of isolated joints with and without transarticular sclerites were measured as the joint was rotated through angles and at angular velocities comparable with those used by walking animals. The procedure was repeated with the joint subjected to different internal fluid pressures in order to assess the potential role of hydraulically induced extension. The efficiency of elastic energy storage (resilience) in the absence of internal fluid pressure was 70-90% for joints with well-developed transarticular sclerites, and the magnitude of torque was similar to those produced by different joint extension mechanisms in other arthropods. Increased internal fluid pressure acted synergistically with transarticular sclerites in some joints but had little or no effect in others. Joints that lacked both extensor muscles and transarticular sclerites appeared to be specialized for hydraulic extension, and joints operated by antagonistic muscles lacked apparent specializations for either elastic or hydraulic extension. It is well known that elastic energy storage is a significant contributor to propulsion in running vertebrates and certain arthropods, where elastic elements are loaded as the center of mass falls during one phase of the locomotor cycle. However, transarticular sclerites are apparently loaded by contraction of flexor muscles when the leg is not in contact with the substratum. Hence the mechanism of a transarticular sclerite is more similar to the flight and jumping mechanisms of other arthropods than to

  6. Voluntary chemical castration of a mental patient.

    Science.gov (United States)

    Brahams, D

    1988-06-01

    Britain's High Court recently overruled two decisions of the Mental Health Act Commission that denied certification of a voluntary experimental drug treatment to a mental patient, holding that the standard for informed consent is determined not by the subjective judgment of the commissioners but by whether the patient knows the nature and likely effects of treatment and that its use in his case is a novel one. The background facts of the case involving a 27-year-old pedophile receiving goserelin implantations to reduce testosterone levels are presented and the issues of jurisdiction under the Mental Health Act 1983 and the commissioners' duty to act fairly and to consider the likely benefits of treatment are discussed.

  7. Analysis of Foot Slippage Effects on an Actuated Spring-mass Model of Dynamic Legged Locomotion

    Directory of Open Access Journals (Sweden)

    Yizhar Or

    2016-04-01

    Full Text Available The classical model of spring-loaded inverted pendulum (SLIP and its extensions have been widely accepted as a simple description of dynamic legged locomotion at various scales in humans, legged robots and animals. Similar to the majority of models in the literature, the SLIP model assumes ideal sticking contact of the foot. However, there are practical scenarios of low ground friction that causes foot slippage, which can have a significant influence on dynamic behaviour. In this work, an extension of the SLIP model with two masses and torque actuation is considered, which accounts for possible slippage under Coulomb’s friction law. The hybrid dynamics of this model is formulated and numerical simulations under representative parameter values reveal several types of stable periodic solutions with stick slip transitions. Remarkably, it is found that slippage due to low friction can sometimes increase average speed and improve energetic efficiency by significantly reducing the mechanical cost of transport.

  8. Lateral asymmetry of voluntary attention orienting

    Directory of Open Access Journals (Sweden)

    B.A. Castro-Barros

    2010-08-01

    Full Text Available We recently demonstrated that automatic attention favors the right side of space and, in the present study, we investigated whether voluntary attention also favors this side. Six reaction time experiments were conducted. In each experiment, 12 new 18-25-year-old male right-handed individuals were tested. In Experiments 1, 2, 3 (a, b and 4 (a, b, tasks with increasing attentional demands were used. In Experiments 1, 2, 3a, and 4a, attention was oriented to one or both sides by means of a central spatially informative visual cue. A left or right side visual target appeared 100, 300, or 500 ms later. Attentional effects were observed in the four experiments. In Experiments 2, 3a and 4a, these effects were greater when the cue indicated the right side than when it indicated the left side (respectively: 16 ± 10 and 44 ± 6 ms, P = 0.015, for stimulus onset asynchrony of 500 ms in Experiment 2; 38 ± 10 and 70 ± 7 ms, P = 0.011, for Experiment 3a, and 23 ± 11 and 61 ± 10 ms, P = 0.009, for Experiment 4a. In Experiments 3b and 4b, the central cue pointed to both sides and was said to be non-relevant for task performance. In these experiments right and left reaction times did not differ. The most conservative interpretation of the present findings is that voluntary attention orienting favors the right side of space, particularly when a difficult task has to be performed.

  9. Computer-assisted detection of nocturnal leg motor activity in patients with restless legs syndrome and periodic leg movements during sleep.

    Science.gov (United States)

    Ferri, Raffaele; Zucconi, Marco; Manconi, Mauro; Bruni, Oliviero; Miano, Silvia; Plazzi, Giuseppe; Ferini-Strambi, Luigi

    2005-08-01

    To assess the performance of a new method for automatic detection of periodic leg movements during sleep. Leg movements during sleep were visually detected in the tibialis anterior muscles recordings of 15 patients with restless legs syndrome and 15 normal controls. Leg movements were detected automatically by means of a new computer method with which electromyogram signals are first digitally band-pass filtered and then rectified; subsequently, the detection of leg movements is performed by using 2 thresholds: one for the starting point and another to detect the end point of each leg movement. Sensitivity and false-positive rate were obtained; the American Sleep Disorders Association parameters were also computed, and the results analyzed by means of the Kendall W coefficient, the linear correlation coefficient and the Bland-Altman plots. N/A. Fifteen patients with restless legs syndrome and periodic leg movements and 15 controls. High values of the Kendall W coefficient of concordance between automatic and visual analysis were found with values close to 1 and the linear correlation coefficient for leg movements index and total leg movements index was > 0.950 (p visual and computer detection, which were -9.01 and +9.89 for the periodic leg movement index. None of the normal controls was found to have periodic leg movement indexes >5 after automatic analysis. Our method can be applied to the clinical evaluation of periodic leg movements during sleep, with some caution in patients with a low periodic leg movement indexes. Large-scale research application is possible and can be considered as reliable.

  10. Voluntary exercise at the expense of reproductive success in Djungarian hamsters ( Phodopus sungorus)

    Science.gov (United States)

    Petri, Ines; Scherbarth, Frank; Steinlechner, Stephan

    2010-09-01

    Energy demands of gestation and lactation represent a severe challenge for small mammals. Therefore, additional energetic burdens may compromise successful breeding. In small rodents, food restriction, cold exposure (also in combination) and wheel running to obtain food have been shown to diminish reproductive outcome. Although exhibited responses such as lower incidence of pregnancy, extended lactation periods and maternal infanticide were species dependent, their common function is to adjust energetic costs to the metabolic state reflecting the trade-off between maternal investment and self-maintenance. In the present study, we sought to examine whether voluntary exercise affects reproduction in Djungarian hamsters ( Phodopus sungorus), which are known for their high motivation to run in a wheel. Voluntary exercise resulted in two different effects on reproduction; in addition to increased infanticide and cannibalism, which was evident across all experiments, the results of one experiment provided evidence that free access to a running wheel may prevent successful pregnancy. It seems likely that the impact of voluntary wheel running on reproduction was associated with a reduction of internal energy resources evoked by extensive exercise. Since the hamsters were neither food-restricted nor forced to run in the present study, an energetic deficit as reason for infanticide in exercising dams would emphasise the particularly high motivation to run in a wheel.

  11. Neuromuscular performance of maximal voluntary explosive concentric contractions is influenced by angular acceleration.

    Science.gov (United States)

    Hahn, D; Bakenecker, P; Zinke, F

    2016-12-28

    Torque production during maximal voluntary explosive contractions is considered to be a functionally more relevant neuromuscular measure than steady-state torque, but little is known about accelerated concentric contractions. This study investigated torque, muscle activity, and fascicle behavior during isometric and fast concentric contractions of quadriceps femoris. Ten participants performed maximal voluntary explosive isometric, isovelocity, and additional concentric knee extensions at angular accelerations ranging from 700 to 4000° s(-2) that resulted in an angular velocity of 300° s(-1) at 40° knee flexion. Concentric torque at 40° knee flexion was corrected for inertia, and the corresponding isometric torque was matched to the time when the target knee angle of 40° was reached during concentric contractions. Electromyography of quadriceps femoris and hamstrings and ultrasound of vastus lateralis were measured to determine muscle activity, fascicle length, and fascicle velocity (FV). The faster the acceleration, the more torque was produced during concentric contractions at 40° knee flexion, which was accompanied by a reduction in FV. In comparison with isometric conditions, concentric quadriceps muscle activity was increased and torque during accelerations ≥3000° s(-2) equaled the time-matched isometric torque. Our results provide novel evidence that acceleration influences torque production during maximal voluntary explosive concentric contractions. This is suggested to be due to series elasticity and reduced force depression.

  12. Simultaneous Knee Extensor Muscle Action Induces an Increase in Voluntary Force Generation of Plantar Flexor Muscles.

    Science.gov (United States)

    Suzuki, Takahito; Shioda, Kohei; Kinugasa, Ryuta; Fukashiro, Senshi

    2017-02-01

    Suzuki, T, Shioda, K, Kinugasa, R, and Fukashiro, S. Simultaneous knee extensor muscle action induces an increase in voluntary force generation of plantar flexor muscles. J Strength Cond Res 31(2): 365-371, 2017-Maximum activation of the plantar flexor muscles is required for various sporting activities that involve simultaneous plantar flexion and knee extension. During a multi-joint movement, activation of the plantar flexor muscles is affected by the activity of the knee extensor muscles. We hypothesized that coactivation of the plantar flexor muscles and knee extensor muscles would result in a higher plantar flexion torque. To test this hypothesis, 8 male volunteers performed maximum voluntary isometric action of the plantar flexor muscles with and without isometric action of the knee extensor muscles. Surface electromyographic data were collected from 8 muscles of the right lower limb. Voluntary activation of the triceps surae muscles, evaluated using the interpolated twitch technique, significantly increased by 6.4 percentage points with intentional knee extensor action (p = 0.0491). This finding is in line with a significant increase in the average rectified value of the electromyographic activity of the vastus lateralis, fibularis longus, and soleus muscles (p = 0.013, 0.010, and 0.045, respectively). The resultant plantar flexion torque also significantly increased by 11.5% of the predetermined maximum (p = 0.031). These results suggest that higher plantar flexor activation coupled with knee extensor activation facilitates force generation during a multi-joint task.

  13. Top Ten Tiks Far Beautiful Legs

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    HERE experts provide women witha guide In better stocking buys. 1. Brightly-colored stockings suchas flaming red or pure blue suit only tall,slim ladies with elegant legs. 2. Opaque stockings, suit only slimlegs. 3. Dark or thinly striped stockings

  14. Clinical aspects of lower leg compartment syndrome

    NARCIS (Netherlands)

    Brand, Johan Gerard Henric van den

    2004-01-01

    A compartment syndrome is a condition in which increased pressure within a limited space compromises the circulation and function of tissues within that space. Although pathofysiology is roughly similar in chronic exertional and acute compartment syndrome of the lower leg, the clinical presentation

  15. Hereditary spherocytosis presenting as indolent leg ulcers

    Directory of Open Access Journals (Sweden)

    Muhammed K

    1997-01-01

    Full Text Available Indolent leg ulcertation, which is the rarest manifestation of hereditary spherocytosis, started at the age of 5 years affecting a 15-year-old boy and his mother is reported. Review of literature showed very few reports from India and abroad. The response to oral folic acid was excellent

  16. An automatic hinge system for leg orthoses

    NARCIS (Netherlands)

    Rietman, J.S.; Goudsmit, J.; Meulemans, D.; Halbertsma, J.P.K.; Geertzen, J.H.B.

    2004-01-01

    This paper describes a new, automatic hinge system for leg orthoses, which provides knee stability in stance, and allows knee-flexion during swing. Indications for the hinge system are a paresis or paralysis of the quadriceps muscles. Instrumented gait analysis was performed in three patients, fitte

  17. Mechanics of six-legged runners.

    Science.gov (United States)

    Full, R J; Tu, M S

    1990-01-01

    Six-legged pedestrians, cockroaches, use a running gait during locomotion. The gait was defined by measuring ground reaction forces and mechanical energy fluctuations of the center of mass in Blaberus discoidalis (Serville) as they travelled over a miniature force platform. These six-legged animals produce horizontal and vertical ground-reaction patterns of force similar to those found in two-, four- and eight-legged runners. Lateral forces were less than half the vertical force fluctuations. At speeds between 0.08 and 0.66 ms-1, horizontal kinetic and gravitational potential energy changes were in phase. This pattern of energy fluctuation characterizes the bouncing gaits used by other animals that run. Blaberus discoidalis attained a maximum sustainable stride frequency of 13 Hz at 0.35 ms-1, the same speed and frequency predicted for a mammal of the same mass. Despite differences in body form, the mass-specific energy used to move the center of mass a given distance (0.9 J kg-1m-1) was the same for cockroaches, ghost crabs, mammals, and birds. Similarities in force production, stride frequency and mechanical energy production during locomotion suggest that there may be common design constraints in terrestrial locomotion which scale with body mass and are relatively independent of body form, leg number and skeletal type.

  18. Well Leg Compartment Syndrome After Abdominal Surgery

    DEFF Research Database (Denmark)

    Christoffersen, Jens Krogh; Hove, Lars Dahlgaard; Mikkelsen, Kim Lyngby;

    2016-01-01

    BACKGROUND: Well leg compartment syndrome (WLCS) is a complication to abdominal surgery. We aimed to identify risk factors for and outcome of WLCS in Denmark and literature. METHODS: Prospectively collected claims to the Danish Patient Compensation Association (DPCA) concerning WLCS after abdominal...

  19. Leg og læring

    DEFF Research Database (Denmark)

    Pedersen, Annette

    2008-01-01

    Leg synes at have et potentiale som metode til at fremme læring. Men hvordan? Legen har en vis grad af parallelitet med den virkelige verden i dens interaktive og relationelle strukturer. Det bliver muligt at finde nye meninger i interaktioner, som refererer til vante interaktionsformer, men alli...

  20. A completely intramedullary leg lengthening device

    NARCIS (Netherlands)

    Aalsma, A.M.M.; Hekman, E.E.G.; Stapert, J.W.J.L.; Grootenboer, H.J.

    1998-01-01

    The procedure and the external fixator for lengthening long bones was developed by G.A. Ilizarov in the late 1960's. This technique has, despite its proven abilities for leg lengthening and correction of angular deformities, some considerable disadvantages for patients. Discomfort, infections and re

  1. Clinical aspects of lower leg compartment syndrome

    NARCIS (Netherlands)

    Brand, Johan Gerard Henric van den

    2004-01-01

    A compartment syndrome is a condition in which increased pressure within a limited space compromises the circulation and function of tissues within that space. Although pathofysiology is roughly similar in chronic exertional and acute compartment syndrome of the lower leg, the clinical

  2. Priming voluntary autobiographical memories: Implications for the organisation of autobiographical memory and voluntary recall processes.

    Science.gov (United States)

    Mace, John H; Clevinger, Amanda M

    2013-01-01

    The goal of this study was to show that voluntary autobiographical memories could be primed by the prior activation of autobiographical memories. Three experiments demonstrated voluntary memory priming with three different approaches. In Experiment 1 primed participants were asked to recall memories from their elementary school years. In a subsequent memory task primed participants were asked to recall memories from any time period, and they produced significantly more memories from their elementary school years than unprimed participants. In Experiment 2 primed participants were asked to recall what they were doing when they had heard various news events occurring between 1998 and 2005. Subsequently these participants produced significantly more memories from this time period than unprimed participants. In Experiment 3 primed participants were asked to recall memories from their teenage years. Subsequently these participants were able to recall more memories from ages 13-15 than unprimed participants, where both had only 1 second to produce a memory. We argue that the results support the notion that episodic memories can activate one another and that some of them are organised according to lifetime periods. We further argue that the results have implications for the reminiscence bump and voluntary recall of the past.

  3. Power output, isometric strength and steadiness in the leg muscles of pre- and postmenopausal women; the effects of hormone replacement therapy.

    Science.gov (United States)

    Carville, Serena F; Rutherford, Olga M; Newham, Di J

    2006-02-01

    There are conflicting reports of the effects of hormone replacement therapy (HRT) on strength preservation in postmenopausal women, while any effect on power output has received little attention. Decreased steadiness of force generation has been reported in older muscles and may be related to the hormonal changes associated with the menopause, but the effect of HRT has not been investigated. We have studied the effect of HRT on strength, power output and isometric force steadiness in healthy women. Sixteen young (aged 27.4 +/- 1.4 years, mean +/- SEM) and 29 postmenopausal women were studied. Fifteen of the latter were taking HRT (68.1 +/- 1.4 years, HRT+) and 14 (70.5 +/- 1.5 years, HRT-) had never done so. During isometric quadriceps contractions the force steadiness (coefficient of variation of force) was measured at 10, 25, 50 and 100% maximum voluntary contraction (MVC). The average power generated by an explosive leg extension was recorded. The HRT- group generated less power (110.2 +/- 7.2 W) than both the HRT+ (136.5 +/- 10.9 W, P = 0.027) and young (136.2 +/- 5.8 W, P = 0.027) subjects. Power output was similar in the HRT+ and younger subjects. The HRT- subjects were weaker than the younger ones (241.3 +/- 14.0 N vs. 297.6 +/- 13 N, P = 0.006). The strength of the HRT+ group (255.5 +/- 14 N) was not significantly different to the other two groups. There was no difference in steadiness between the three groups at any of the force levels. HRT appears to maintain power output to a greater extent than isometric strength in postmenopausal women. There was no evidence for an effect of either age or HRT on isometric steadiness in the quadriceps.

  4. 76 FR 16000 - Voluntary Protection Programs Information; Extension of the Office of Management and Budget's...

    Science.gov (United States)

    2011-03-22

    ...-evaluations for applicants/ participants subject to OSHA's Process Safety Management (PSM) Standard... covered under the PSM standard must submit responses to the PSM application supplement along with their... its continued adherence to programmatic requirements. Applicants covered under the PSM standard...

  5. A colored leg banding technique for Amazona parrots

    Science.gov (United States)

    Meyers, J.M.

    1995-01-01

    A technique for individual identification of Amazona was developed using plastic leg bands. Bands were made from 5- and 7-mm-wide strips of laminated PVC coiled 2.5 times with an inside diameter 4-5 mm gt the maximum diameter of the parrot's leg. Seventeen parrots were captured in Puerto Rico, marked with individual plastic leg bands, and observed for 204-658 d with only one lost or damaged plastic band. Plastic leg bands did not cause injury to or calluses on parrots' legs. The plastic material used for making leg bands was available in 18 colors in 1994, which would allow unique marking of 306 individuals using one plastic leg band on each leg.

  6. APAs Constraints to Voluntary Movements: The Case for Limb Movements Coupling

    Science.gov (United States)

    Baldissera, Fausto G.; Tesio, Luigi

    2017-01-01

    When rhythmically moving two limbs in either the same or in opposite directions, one coupling mode meets constraints that are absent in the other mode. Isodirectional (ISO) flexion-extensions of the ipsilateral hand and foot can be easily performed with either the hand prone or supine. Instead, antidirectional (ANTI) movements require attentive effort and irresistibly tend to reverse into ISO when frequency increases. Experimental evidence indicates that the direction dependent easy-difficult dichotomy is caused by interference of the anticipatory postural commands associated to movements of one limb with voluntary commands to the other limb. Excitability of the resting wrist muscles is subliminally modulated at the period of ipsilateral foot oscillations, being phase-opposite in the antagonists and distributed so as to facilitate ISO and obstacle ANTI coupling of the hand (either prone or supine) with the foot. Modulation is driven by cortical signals dispatched to the forearm simultaneously with the voluntary commands moving the foot. If right foot oscillations are performed when standing on the left foot with the right hand touching a fixed support, the subliminal excitability modulation is replaced by overt contractions of forearm muscles conforming the APAs features. This suggests that during hand-foot ANTI coupling the voluntary commands to forearm muscles are contrasted by APAs commands of opposite sign linked to foot oscillations. Correlation between the easy-difficult dichotomy and the APAs distribution is also found in coupled adduction-abduction of the arms or hands in the transverse plane and in coupled flexion-extension of the arms in the parasagittal plane. In all these movements, APAs commands linked to the movement of each limb reach the motor pathways to the contralateral muscles homologous to the prime movers and can interfere during coupling with their voluntary activation. APAs are also generated in postural muscles of trunk and lower limbs and

  7. Land Use and Land Cover - MO 2008 Brownfields Voluntary Cleanup Program Sites (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The Brownfields/Voluntary Cleanup Program (BVCP) provides property buyers, sellers, developers, bankers, development agencies, local government and other voluntary...

  8. Muscle functional MRI analysis of trunk muscle recruitment during extension exercises in asymptomatic individuals.

    Science.gov (United States)

    De Ridder, E M D; Van Oosterwijck, J O; Vleeming, A; Vanderstraeten, G G; Danneels, L A

    2015-04-01

    The present study examined the activity levels of the thoracic and lumbar extensor muscles during different extension exercise modalities in healthy individuals. Therefore, 14 subjects performed four different types of extension exercises in prone position: dynamic trunk extension, dynamic-static trunk extension, dynamic leg extension, and dynamic-static leg extension. Pre- and post-exercise muscle functional magnetic resonance imaging scans from the latissimus dorsi, the thoracic and lumbar parts of the longissimus, iliocostalis, and multifidus were performed. Differences in water relaxation values (T2-relaxation) before and after exercise were calculated (T2-shift) as a measure of muscle activity and compared between extension modalities. Linear mixed-model analysis revealed higher lumbar extensor activity during trunk extension compared with leg extension (T2-shift of 5.01 ms and 3.55 ms, respectively) and during the dynamic-static exercise performance compared with the dynamic exercise performance (T2-shift of 4.77 ms and 3.55 ms, respectively). No significant differences in the thoracic extensor activity between the exercises could be demonstrated. During all extension exercises, the latissimus dorsi was the least activated compared with the paraspinal muscles. While all extension exercises are equivalent effective to train the thoracic muscles, trunk extension exercises performed in a dynamic-static way are the most appropriate to enhance lumbar muscle strength.

  9. Protection by S-2-(3-aminopropylamino)ethylphosphorothioic acid against radiation-induced leg contractures in mice. [Gamma Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, N.; Milas, L.

    1983-04-01

    S-2-(3-Aminopropylamino)ethylphosphorothioic acid (WR-2721) was shown to provide marked protection against development of radiation-induced leg contractures in C3Hf/Kam mice whose legs were exposed to single doses of gamma-radiation. The radiation doses ranged from 3300 to 6200 rads delivered to the right hind thighs from two parallelly opposed 137Cs sources. WR-2721 was given i.p. 30 min before irradiation. The severity of radiation-induced leg contractures in untreated and WR-2721-treated mice was followed for 342 days after irradiation. The degree of leg contractures in both control and WR-2721-treated mice increased up to 100 days after radiation, when the change stabilized, remaining more or less at the same level to the end of the observation period. During this entire period, the severity of contractures was less in WR-2721-treated mice. The dose-modifying factor for the level of 5 mm reduction in leg extension was 1.5 at 182 days after irradiation. Since WR-2721 did not prevent the radiocurability of 8-mm fibrosarcomas growing in the same legs, these data imply that WR-2721 has a high potential for increasing therapeutic gain when combined with irradiation in the treatment of tumors of an appreciable size.

  10. How to Treat Restless Leg Syndrome with Traditional Chinese Medicine?

    Institute of Scientific and Technical Information of China (English)

    林宗广

    2003-01-01

    @@ In clinic, restless leg syndrome manifests to have thesymptoms of unbearable soreness, numbness,insect-crawling like itching and electric-shock likeburning sensation in the deep muscles of both legs,which generally appear symmetrically, or severer inone leg, and attack mostly in the night before sleep,but rarely in the day time.

  11. Leg intravenous pressure during head-up tilt.

    NARCIS (Netherlands)

    Groothuis, J.T.; Poelkens, F.; Wouters, C.W.; Kooijman, M.; Hopman, M.T.E.

    2008-01-01

    Leg vascular resistance is calculated as the arterial-venous pressure gradient divided by blood flow. During orthostatic challenges it is assumed that the hydrostatic pressure contributes equally to leg arterial, as well as to leg venous pressure. Because of venous valves, one may question whether,

  12. Lower leg electrical impedance after distal bypass surgery

    DEFF Research Database (Denmark)

    Belanger, G K; Bolbjerg, M L; Heegaard, N H;

    1998-01-01

    Electrical impedance was determined in 13 patients following distal bypass surgery to evaluate lower leg oedema as reflected by its circumference. Tissue injury was assessed by the plasma concentration of muscle enzymes. After surgery, the volume of the control lower leg increased from 1250 (816...... to be a useful method for the evaluation of lower leg oedema after distal bypass surgery....

  13. Protection against high intravascular pressure in giraffe legs

    DEFF Research Database (Denmark)

    Petersen, Karin K; Hørlyck, Arne; Østergaard, Kristine Hovkjær

    2013-01-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination...

  14. Voluntary Noise Mapping for Smart City

    Science.gov (United States)

    Poslončec-Petrić, V.; Vuković, V.; Frangeš, S.; Bačić, Ž.

    2016-09-01

    One of the main concept objectives of smart cities is to create a quality living environment that is long-term sustainable and economically justified. In that context, modern cities are aware of the exposure to various forms of physical and non-physical pollution that needs to be remediated, eliminated or reduced. To achieve that it is necessary to quality determine the sources and reasons of each pollution. The most prominent examples of physical pollution that affects the quality of life of citizens in cities are light and noise pollution. Noise pollution or noise, is mostly the consequence of road and rail traffic in cities and it directly affects the health of citizens. Traffic control, reduction of peak congestion, dispersion and traffic redirection or building protective barriers, are ways that cities use to reduce the amount of noise or its effects. To make these measures efficient it is necessary to obtain the information related to the level of noise in certain areas, streets, cities. To achieve this, smart cities use noise mapping. The city of Zagreb since 2012, participates in the i-SCOPE project (interoperable Smart City services trough Open Platform for urban Ecosystems). i-SCOPE delivers an open platform on top of which it develops, three "smart city" services: optimization of energy consumption through a service for accurate assessment of solar energy potential and energy loss at building level, environmental monitoring through a real-time environmental noise mapping service leveraging citizen's involvement will who act as distributed sensors city-wide measuring noise levels through an application on their mobile phones and improved inclusion and personal mobility of aging and diversely able citizens through an accurate personal routing service. The students of Faculty of Geodesy University of Zagreb, who enrolled in the course Thematic Cartography, were actively involved in the voluntary data acquisition in order to monitor the noise in real time

  15. VOLUNTARY NOISE MAPPING FOR SMART CITY

    Directory of Open Access Journals (Sweden)

    V. Poslončec-Petrić

    2016-09-01

    Full Text Available One of the main concept objectives of smart cities is to create a quality living environment that is long-term sustainable and economically justified. In that context, modern cities are aware of the exposure to various forms of physical and non-physical pollution that needs to be remediated, eliminated or reduced. To achieve that it is necessary to quality determine the sources and reasons of each pollution. The most prominent examples of physical pollution that affects the quality of life of citizens in cities are light and noise pollution. Noise pollution or noise, is mostly the consequence of road and rail traffic in cities and it directly affects the health of citizens. Traffic control, reduction of peak congestion, dispersion and traffic redirection or building protective barriers, are ways that cities use to reduce the amount of noise or its effects. To make these measures efficient it is necessary to obtain the information related to the level of noise in certain areas, streets, cities. To achieve this, smart cities use noise mapping. The city of Zagreb since 2012, participates in the i-SCOPE project (interoperable Smart City services trough Open Platform for urban Ecosystems. i-SCOPE delivers an open platform on top of which it develops, three "smart city" services: optimization of energy consumption through a service for accurate assessment of solar energy potential and energy loss at building level, environmental monitoring through a real-time environmental noise mapping service leveraging citizen's involvement will who act as distributed sensors city-wide measuring noise levels through an application on their mobile phones and improved inclusion and personal mobility of aging and diversely able citizens through an accurate personal routing service. The students of Faculty of Geodesy University of Zagreb, who enrolled in the course Thematic Cartography, were actively involved in the voluntary data acquisition in order to monitor the

  16. Interaction of Compliance and Voluntary Renewable Energy Markets

    Energy Technology Data Exchange (ETDEWEB)

    Bird, L.; Lokey, E.

    2007-10-01

    In recent years, both compliance and voluntary markets have emerged to help support the development of renewable energy resources. Both of these markets are growing rapidly and today about half of U.S. states have RPS policies in place, with a number of these policies adopted in the last several years. In addition, many states have recently increased the stringency of their RPS policies. This paper examines key market interaction issues between compliance and voluntary renewable energy markets. It provides an overview of both the compliance and voluntary markets, addressing each market's history, purpose, size, scope, and benefits while addressing issues, including double counting.

  17. Interaction of Compliance and Voluntary Renewable Energy Markets

    Energy Technology Data Exchange (ETDEWEB)

    Bird, Lori [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lokey, Elizabeth [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2007-10-01

    In recent years, both compliance and voluntary markets have emerged to help support the development of renewable energy resources. Both of these markets are growing rapidly and today about half of U.S. states have RPS policies in place, with a number of these policies adopted in the last several years. In addition, many states have recently increased the stringency of their RPS policies. This paper examines key market interaction issues between compliance and voluntary renewable energy markets. It provides an overview of both the compliance and voluntary markets, addressing each market's history, purpose, size, scope, and benefits while addressing issues, including double counting.

  18. Ecological Research of the Voluntary Disclosure about Listed Companies

    Science.gov (United States)

    Hu, Jing-Jing; Yan, Guang-Le

    In the paper, the research subject is the ecological relationship between the Small and Medium-sized Enterprises(SMEs) and the Large-scale Enterprises(Les). From the perspective of ecology, setting up the competitive model basic on the Logistic model, and carrying out further analysis about the voluntary information disclosure of listed company, then getting the strategic choice about the voluntary information disclosure and the ecological explanation of false information, and the dynamic mechanism and strategy of the voluntary information disclosure of listed company.

  19. Is leg muscle strength correlated with functional balance and mobility among inpatients in geriatric rehabilitation?

    Science.gov (United States)

    Hasselgren, Låtta; Olsson, Lillemor Lundin; Nyberg, Lars

    2011-01-01

    Determinants of functional balance and mobility have rarely been investigated in geriatric wards. This study examined if leg muscle strength correlates to functional balance and mobility among geriatric inpatients. Fifty inpatients, 29 women and 21 men (mean age 79.6 years) were included. Functional balance was assessed with the Berg Balance Scale (BBS) and mobility was assessed with the Physiotherapy Clinical Outcome Variable Scale (COVS). Strength in the leg extension muscles was measured as 1 Repetition Maximum (1RM) in a leg press and strength in the ankle muscles was measured with Medical Research Council grades (MRC, 0-5). The sum scores, and most of the single items, of the BBS and the COVS significantly correlated to 1RM/body weight, ankle dorsiflexion, and plantar flexion. In a stepwise multiple regression, ankle dorsiflexion and 1RM/body weight together accounted for 39% of the variance of the BBS and 41% of the variance of the COVS. Estimated values of the BBS and the COVS can be calculated from the equation. In clinical work, the knowledge about how leg muscle strength associates with balance and mobility may be useful in analyzing underlying causes of reduced balance and mobility function, and in planning rehabilitation programs.

  20. Ulcer pain in patients with venous leg ulcers related to antibiotic treatment and compression therapy.

    Science.gov (United States)

    Akesson, Nina; Oien, Rut Frank; Forssell, Henrik; Fagerström, Cecilia

    2014-09-01

    The aim of this study was to compare venous leg ulcer patients with and without ulcer pain to see whether ulcer pain affected the use of antibiotic treatment and compression therapy throughout healing. A total of 431 patients with venous leg ulcers were included during the study period. Every patient was registered in a national quality registry for patients with hard-to-heal leg, foot, and pressure ulcers. A high incidence of ulcer pain (57%) was found when the patients entered the study. Patients with ulcer pain had been treated more extensively with antibiotics both before and during the study period. Throughout healing there was a significant reduction of antibiotic use among patients in the 'no pain' group, from 44% to 23% (P=0.008). There was no significant difference between the two groups concerning compression therapy (85% vs. 88%), but 12% of patients in the 'pain' group did not get their prescribed compression compared with 6% of patients in the 'no pain' group. The groups did not differ significantly in terms of ulcer duration, ulcer size or healing time. This study shows a high incidence of ulcer pain, confirming that pain has a great impact on patients with venous leg ulcers. Results further suggest that the presence of ulcer pain increases the prescription of antibiotics but does not affect the use of compression therapy. Several advantages were found from using a national quality registry. The registry is a valuable clinical tool showing the importance of accurate diagnosis and effective treatment.

  1. A Kinematic Analysis of the Jumping Front-Leg Axe-Kick in Taekwondo.

    Science.gov (United States)

    Preuschl, Emanuel; Hassmann, Michaela; Baca, Arnold

    2016-03-01

    The jumping front-leg axe-kick is a valid attacking and counterattacking technique in Taekwondo competition (Streif, 1993). Yet, the existing literature on this technique is sparse (Kloiber et al., 2009). Therefore, the goal of this study was to determine parameters contributing significantly to maximum linear speed of the foot at impact. Parameters are timing of segment and joint angular velocity characteristics and segment lengths of the kicking leg. Moreover, we were interested in the prevalence of proximal-to-distal-sequencing. Three-dimensional kinematics of the kicks of 22 male Taekwondo-athletes (age: 23.3 ± 5.3 years) were recorded via a motion capturing system (Vicon Motion Systems Limited, Oxford, UK). The participants performed maximum effort kicks onto a rack-held kicking pad. Only the kick with the highest impact velocity was analysed, as it was assumed to represent the individual's best performance. Significant Pearson correlations to impact velocity were found for pelvis tilt angular displacement (r = 0.468, p taekwondo athlete's do not influence their impact velocities.In order to raise the impact velocity in the jumping front-leg axe-kick an athlete should avoid tilting back with the torso. Instead, an upright position should be maintained.In the leg-lowering period, we suggest hitting the target by using hip extension with a rather straight knee, instead of flexing the knee.

  2. Crystal structure of Legionella pneumophila type IV secretion system effector LegAS4.

    Science.gov (United States)

    Son, Jonghyeon; Jo, Chang Hwa; Murugan, Ravichandran N; Bang, Jeong Kyu; Hwang, Kwang Yeon; Lee, Woo Cheol

    2015-10-02

    The SET domain of LegAS4, a type IV secretion system effector of Legionella pneumophila, is a eukaryotic protein motif involved in histone methylation and epigenetic modulation. The SET domain of LegAS4 is involved in the modification of Lys4 of histone H3 (H3K4) in the nucleolus of the host cell, thereby enhancing heterochromatic rDNA transcription. Moreover, LegAS4 contains an ankyrin repeat domain of unknown function at its C-terminal region. Here, we report the crystal structure of LegAS4 in complex with S-adenosyl-l-methionine (SAM). Our data indicate that the ankyrin repeats interact extensively with the SET domain, especially with the SAM-binding amino acids, through conserved residues. Conserved surface analysis marks Glu159, Glu203, and Glu206 on the SET domain serve as candidate residues involved in interaction with the positively charged histone tail. Conserved surface residues on the ankyrin repeat domain surround a small pocket, which is suspected to serve as a binding site for an unknown ligand.

  3. Bio-Inspired Controller for a Robot Cheetah with a Neural Mechanism Controlling Leg Muscles

    Institute of Scientific and Technical Information of China (English)

    Xin Wang; Mantian Li; Pengfei Wang; Wei Guo; Lining Sun

    2012-01-01

    The realization of a high-speed running robot is one of the most challenging problems in developing legged robots.The excellent performance of cheetahs provides inspiration for the control and mechanical design of such robots.This paper presents a three-dimensional model of a cheetah that predicts the locomotory behaviors of a running cheetah.Applying biological knowledge of the neural mechanism,we control the muscle flexion and extension during the stance phase,and control the positions of the joints in the flight phase via a PD controller to minimize complexity.The proposed control strategy is shown to achieve similar locomotion of a real cheetah.The simulation realizes good biological properties,such as the leg retraction,ground reaction force,and spring-like leg behavior.The stable bounding results show the promise of the controller in high-speed locomotion.The model can reach 2.7 m·s- 1 as the highest speed,and can accelerate from 0 to 1.5 m·s -1 in one stride cycle.A mechanical structure based on this simulation is designed to demonstrate the control approach,and the most recently developed hindlimb controlled by the proposed controller is presented in swinging-leg experiments and jump-force experiments.

  4. Single Phase Online UPS Design Using Three Leg Converters

    Directory of Open Access Journals (Sweden)

    R. Ramesh,

    2014-03-01

    Full Text Available The single phase online UPS integrate with the three leg type converter which operate with battery charger and the inverter. The first leg controls the ability of charging battery. The third leg controls the output voltage. The common leg is used to control the line frequency. The battery charger has the ability of making the correction of power factor during the battery charging. The inverter is used to maintain the output voltage and to limit the output current. The main feature of the three leg converter is used to reduce the number of switching devices. So that the system has the low value of power loss and low cost.

  5. Corporate volunteering - motivation for voluntary work

    Directory of Open Access Journals (Sweden)

    Debora Azevedo

    2008-07-01

    Full Text Available Nowadays, when the welfare state is a responsibility of the entire society, organizations in the private sector assume co-responsibility for social issues. They are also pressured by the challenges presented by technological advances and the globalization , involving new parameters and requirements for quality. In this context, the concept of Corporate Social Responsibility (RSC emerges as an option for solutions to the issues related to the company and the whole community. Among the actions of the RSC is the Corporate Volunteering-program, which aims to promote / encourage employes to do voluntary work. A central issue when talking about volunteering is the withdrawal of these (SILVA and FEITOSA, 2002; TEODÓSIO, 1999 and, in accordance with the Community Solidarity (1997, one of the possible causes for the withdrawal is the lack of clarity as to the motives and expectations that lead the person to volunteer themselves. This study uses qualitative research and triangulation of feedback from volunteers, coordinators of volunteers and social organizations, to present a framework from which it is possible to analyze the various motivations for the volunteer work. Key words: Corporate Volunteering program. Volunteering. Corporate social responsibility.

  6. Expectations and voluntary attrition in nursing students.

    Science.gov (United States)

    O'Donnell, Hugh

    2011-01-01

    This paper presents a series of findings generated during a larger study which aimed to develop a theoretical understanding of the reasons why nursing students voluntarily leave pre-registration nursing programmes. In this study, significant incongruence was found to exist between student expectations of pre-registration nursing programmes and the reality of these programmes following entry. The resulting dissonance was identified as an important factor in student decisions to voluntarily withdraw. A single case study design was selected to explore the causes of voluntary attrition in nursing students within a School of Nursing and Midwifery. The study population was obtained through purposeful sampling and consisted of 15 students who had previously voluntarily withdrawn from pre-registration nursing programmes. A semi-structured interview method was used to collect data from study participants. The interview schedule developed for use in the study reflected the key components of the conceptual model of higher education (HE) student attrition (Tinto, 1975, 1987, 1993). All interviews were tape recorded to facilitate later transcription. The Cyclical or Interactive Model of Qualitative Research (Miles and Huberman, 1994) was used to analyse data collected from study participants. This paper describes the unrealistic range of expectations which nursing students have of nursing, the information sources and experiences which inform student expectations and how ambiguous expectations contributed to voluntarily attrition.

  7. Perceived coercion in voluntary hospital admission.

    LENUS (Irish Health Repository)

    O'Donoghue, Brian

    2014-01-30

    The legal status of service users admitted to psychiatric wards is not synonymous with the level of coercion that they can perceive during the admission. This study aimed to identify and describe the proportion of individuals who were admitted voluntarily but experienced levels of perceived coercion comparable to those admitted involuntarily. Individuals admitted voluntarily and involuntarily to three psychiatric hospitals were interviewed using the MacArthur Admission Experience Interview and the Structured Clinical Interview for DSM-IV diagnoses. One hundered sixty-one individuals were interviewed and 22% of the voluntarily admitted service users had levels of perceived coercion similar to that of the majority of involuntarily admitted service users. Voluntarily admitted service users who experienced high levels of perceived coercion were more likely to have more severe psychotic symptoms, have experienced more negative pressures and less procedural justices on admission. Individuals brought to hospital under mental health legislation but who subsequently agreed to be admitted voluntarily and those treated on a secure ward also reported higher levels of perceived coercion. It needs to be ensured that if any service user, whether voluntary or involuntary, experiences treatment pressures or coercion that there is sufficient oversight of the practice, to ensure that individual\\'s rights are respected.

  8. Multi-leg heat pipe evaporator

    Science.gov (United States)

    Alario, J. P.; Haslett, R. A. (Inventor)

    1986-01-01

    A multileg heat pipe evaporator facilitates the use and application of a monogroove heat pipe by providing an evaporation section which is compact in area and structurally more compatible with certain heat exchangers or heat input apparatus. The evaporation section of a monogroove heat pipe is formed by a series of parallel legs having a liquid and a vapor channel and a communicating capillary slot therebetween. The liquid and vapor channels and interconnecting capillary slots of the evaporating section are connected to the condensing section of the heat pipe by a manifold connecting liquid and vapor channels of the parallel evaporation section legs with the corresponding liquid and vapor channels of the condensing section.

  9. Clinical quality indicators of venous leg ulcers

    DEFF Research Database (Denmark)

    Kjaer, Monica L; Mainz, Jan; Soernsen, Lars T

    2005-01-01

    and reliable evidence-based quality indicators of venous leg ulcer care. A Scandinavian multidisciplinary, cross-sectional panel of wound healing experts developed clinical quality indicators on the basis of scientific evidence from the literature and subsequent group nominal consensus of the panel......%) were assessed for venous surgery. Distal arterial pressure was measured following initial examination in 33 of the patients (34%). All patients (100%) were prescribed compression therapy. Of the 98 patients, 11 (11%) had ulcers recur in 3 months and 72 (73%) healed in 12 months, which is in line......; an independent medical doctor tested the feasibility and reliability of these clinical indicators, assessing the quality of medical technical care on 100 consecutive venous leg ulcer patients. Main outcome measures were healing, recurrence, pain, venous disease diagnosis, differential diagnosis and treatment...

  10. Multi-leg heat pipe evaporator

    Science.gov (United States)

    Alario, J. P.; Haslett, R. A.

    1986-04-01

    A multileg heat pipe evaporator facilitates the use and application of a monogroove heat pipe by providing an evaporation section which is compact in area and structurally more compatible with certain heat exchangers or heat input apparatus. The evaporation section of a monogroove heat pipe is formed by a series of parallel legs having a liquid and a vapor channel and a communicating capillary slot therebetween. The liquid and vapor channels and interconnecting capillary slots of the evaporating section are connected to the condensing section of the heat pipe by a manifold connecting liquid and vapor channels of the parallel evaporation section legs with the corresponding liquid and vapor channels of the condensing section.

  11. Pharmacologic treatment of venous leg ulcers.

    Science.gov (United States)

    Dormandy, J A

    1995-01-01

    In terms of prevalence, total cost and morbidity, venous leg ulcers are probably by far the most important type of ulcerations in the leg. The macrocirculatory defect leading to a raised ambulatory venous pressure is now accepted as a common initial pathologic pathway. Most current treatment modalities, such as surgery or external compression, are designed to control the macrovascular defect. However, it is the microcirculatory consequences of the venous hypertension that give rise to the trophic skin changes and ultimately to ulceration. At this microcirculatory level, pharmacotherapy may be a useful adjunct in the treatment of venous leg ulcers. The microcirculatory pathophysiologic changes include decreased fibrinolytic activity, elevated plasma fibrinogen, microcirculatory thrombi, and inappropriate activation of the white blood cells. The oxidative burst from the activated white cells probably plays a key role by releasing locally leukocyte-derived free radicals, proteolytic enzymes, cytokines, platelet-activating factor, and a number of other noxious mediators. An important additional component in recalcitrant venous ulcers is co-existing arterial disease, which is probably present in 15-20% of cases. Decreased arterial perfusion pressure will further aggravate the ischemic changes caused by the venous hypertension. Pentoxifylline downregulates leukocyte activation, reduces leukocyte adhesion, and also has fibrinolytic effects. A number of clinical studies have therefore been carried out to examine the clinical efficacy of pentoxifylline in treatment of venous leg ulcers. Probably the largest published placebo-controlled, double-blind randomized study was reported in 1990. In this study, 80 patients received either pentoxifylline 400 mg three times a day orally or matching placebo for 6 months or until their reference ulcer healed if this occurred sooner. Complete healing of the reference ulcer occurred in 23 of the 38 patients treated with pentoxifylline

  12. Restless Legs Syndrome and Psychiatric Disorders.

    Science.gov (United States)

    Mackie, Susan; Winkelman, John W

    2015-09-01

    There are strong epidemiologic ties between restless legs syndrome (RLS) and a wide array of psychiatric conditions. Although the mechanism of this association is not fully understood, there are likely bidirectional cause-and-effect relationships. Appreciation of psychiatric comorbidity is an essential component of the treatment of RLS. Clinicians should be prepared to facilitate appropriate psychiatric treatment and consider the complex interactions between psychiatric medications, RLS medications, and the clinical course of both illnesses.

  13. Visual based localization for a Legged Robot

    OpenAIRE

    Martín Rico, Francisco; Matellán Olivera, Vicente; González-Careaga, Rafaela; Barrera González, Pablo; Cañas, José María

    2006-01-01

    P. 708-715 This paper presents a visual based localization mechanism for a legged robot. Our proposal, fundamented on a probabilistic approach, uses a precompiled topological map where natural landmarks like doors or ceiling lights are recognized by the robot using its on-board camera. Experiments have been conducted using the AIBO Sony robotic dog showing that it is able to deal with noisy sensors like vision and to approximate world models representing indoor of c...

  14. Vision based behaviors for a legged robot

    OpenAIRE

    Ruiz, Juan V.; Montero, Pablo; Martín Rico, Francisco; Matellán Olivera, Vicente

    2005-01-01

    This article describes two vision-based behaviors designed for an autonomous legged robot. These behaviors have been designed in a modular way in order to be able to integrate them in an architecture named DSH (Dynamic Schema Hierarchies), which is also briefly described. These behaviors have been tested in office indoor environments and experiments carried out are also described in this paper. The platform used in these experiments carried out are also described in theis paper. The platform ...

  15. Clinical Value of the Assessment of Changes in MEP Duration with Voluntary Contraction.

    Science.gov (United States)

    Brum, Marisa; Cabib, Christopher; Valls-Solé, Josep

    2015-01-01

    Transcranial magnetic stimulation (TMS) gives rise to muscle responses, known as motor evoked potentials (MEP), through activation of the motor pathways. Voluntary contraction causes facilitation of MEPs, which consists of shortening MEP latency, increasing MEP amplitude and widening MEP duration. While an increase in excitability of alpha motorneurons and the corticospinal tract can easily explain latency shortening and amplitude increase, other mechanisms have to be accounted for to explain the increase in duration. We measured the increase in duration of the MEP during contraction with respect to rest in a group of healthy volunteers and retrospectively assessed this parameter in patients who were examined in a standardized fashion during the past 5 years. We included 25 healthy subjects, 21 patients with multiple sclerosis, 33 patients with acute stroke, 5 patients with hereditary spastic paraparesis, and 5 patients with signs suggesting psychogenic paresis. We found already significant differences among groups in the MEP duration at rest, patients with MS had a significantly longer duration, and patients with stroke had significantly shorter duration, than the other two groups. The increase in MEP duration during voluntary contraction was different in patients and in healthy subjects. It was significantly shorter in MS and significantly longer in stroke patients. It was absent in the five patients with suspected psychogenic weakness. In patients with HSP, an abnormally increase in duration occurred only in leg muscles. Our results suggest that the increase in duration of the MEP during contraction may reveal the contribution of propriospinal interneurons to the activation of alpha motorneurons. This mechanism may be altered in some diseases and, therefore, the assessment proposed in this work may have clinical applicability for the differential diagnosis of weakness.

  16. Clinical value of the assessment of changes in MEP duration with voluntary contraction

    Directory of Open Access Journals (Sweden)

    Josep eValls-Sole

    2016-01-01

    Full Text Available Transcranial magnetic stimulation (TMS gives rise to muscle responses, known as motor evoked potentials (MEP, through activation of the motor pathways. Voluntary contraction causes facilitation of MEPs, which consists of shortening MEP latency, increasing MEP amplitude and widening MEP duration. While an increase in excitability of alpha motorneurons and the corticospinal tract can easily explain latency shortening and amplitude increase, other mechanisms have to be accounted for to explain the increase in duration. We measured the extent of the increase in duration that adds at the end of the MEP during contraction with respect to rest in a group of healthy volunteers and retrospectively assessed this parameter in patients who were examined in a standardized fashion during the past 5 years. We included 25 healthy subjects, 21 patients with multiple sclerosis, 33 patients with acute stroke, 5 patients with hereditary spastic paraparesis and 5 patients with signs suggesting psychogenic paresis. We found already significant differences among groups in the MEP duration at rest, patients with MS had a significantly longer duration, and patients with stroke had significantly shorter duration, than the other two groups. The increase in MEP duration during voluntary contraction was different in patients and in healthy subjects. It was significantly shorter in MS and significantly longer in stroke patients. It was absent in the 5 patients with suspected psychogenic weakness. In patients with HSP, an abnormally increase in duration occurred only in leg muscles. Our results suggest that the increase in duration of the MEP during contraction may reveal the contribution of propriospinal interneurons to the activation of alpha motorneurons. This mechanism may be altered in some diseases and, therefore, the assessment proposed in this work may have clinical applicability for the differential diagnosis of weakness.

  17. Association of Quadriceps Strength and Psychosocial Factors With Single-Leg Hop Performance in Patients With Meniscectomy.

    Science.gov (United States)

    Hsu, Chao-Jung; George, Steven Z; Chmielewski, Terese L

    2016-12-01

    Clinicians use the single-leg hop test to assess readiness for return to sports after knee injury. Few studies have reported the results of single-leg hop testing after meniscectomy. Additionally, the contributions of impairments in quadriceps strength and psychosocial factors to single-leg hop performance are unknown. To compare single-leg hop performance (distance and landing mechanics) between limbs and to examine the association of single-leg hop performance with quadriceps strength and psychosocial factors in patients with meniscectomy. Descriptive laboratory study. A total of 22 subjects who underwent meniscectomy for traumatic meniscal tears received either standard rehabilitation alone or with additional quadriceps strengthening. Testing was conducted immediately postrehabilitation and at 1 year postsurgery. A single-leg hop test was performed bilaterally, and hop distance was used to create a hop symmetry index. Landing mechanics (peak knee flexion angle, knee extension moment, and peak vertical ground-reaction force) were analyzed with a motion-capture system and a force plate. An isokinetic dynamometer (60 deg/s) assessed knee extensor peak torque and rate of torque development (RTD0-200ms and RTD0-peak torque). Questionnaires assessed fear of reinjury (Tampa Scale for Kinesiophobia [TSK-11]) and self-efficacy (Knee Activity Self-Efficacy [KASE]). Rehabilitation groups did not significantly differ in single-leg hop performance; therefore, groups were combined for further analyses. The mean hop symmetry index was 88.6% and 98.9% at postrehabilitation and 1 year postsurgery, respectively. Compared with the nonsurgical limb, the surgical limb showed decreased peak knee flexion angle at postrehabilitation and decreased knee extension moment at 1 year postsurgery. The hop symmetry index was positively associated with peak torque, RTD0-200ms, and the KASE score at postrehabilitation. Moreover, at postrehabilitation, the peak knee flexion angle was positively

  18. Legged-locomotion on inclined granular media

    Science.gov (United States)

    Rieser, Jennifer; Qian, Feifei; Goldman, Daniel

    Animals traverse a wide variety of complex environments, including situations in which the ground beneath them can yield (e.g. dry granular media in desert dunes). Locomotion strategies that are effective on level granular media can fail when traversing a granular slope. Taking inspiration from successful legged-locomotors in sandy, uneven settings, we explore the ability of a small (15 cm long, 100 g), six-c-shaped legged robot to run uphill in a bed of 1-mm-diameter poppy seeds, using an alternating tripod gait. Our fully automated experiments reveal that locomotor performance can depend sensitively on both environmental parameters such as the inclination angle and volume fraction of the substrate, and robot morphology and control parameters like leg shape, step frequency, and the friction between the feet of the robot and the substrate. We assess performance by measuring the average speed of the robot, and we find that the robot tends to perform better at higher step frequency and lower inclination angles, and that average speed decreases more rapidly with increasing angle for higher step frequency.

  19. Proprioceptive Actuation Design for Dynamic Legged locomotion

    Science.gov (United States)

    Kim, Sangbae; Wensing, Patrick; Biomimetic Robotics Lab Team

    Designing an actuator system for highly-dynamic legged locomotion exhibited by animals has been one of the grand challenges in robotics research. Conventional actuators designed for manufacturing applications have difficulty satisfying challenging requirements for high-speed locomotion, such as the need for high torque density and the ability to manage dynamic physical interactions. It is critical to introduce a new actuator design paradigm and provide guidelines for its incorporation in future mobile robots for research and industry. To this end, we suggest a paradigm called proprioceptive actuation, which enables highly- dynamic operation in legged machines. Proprioceptive actuation uses collocated force control at the joints to effectively control contact interactions at the feet under dynamic conditions. In the realm of legged machines, this paradigm provides a unique combination of high torque density, high-bandwidth force control, and the ability to mitigate impacts through backdrivability. Results show that the proposed design provides an impact mitigation factor that is comparable to other quadruped designs with series springs to handle impact. The paradigm is shown to enable the MIT Cheetah to manage the application of contact forces during dynamic bounding, with results given down to contact times of 85ms and peak forces over 450N. As a result, the MIT Cheetah achieves high-speed 3D running up to 13mph and jumping over an 18-inch high obstacle. The project is sponsored by DARPA M3 program.

  20. Aloe Vera and Infected Leg Ulcers

    Directory of Open Access Journals (Sweden)

    Asima Banu

    2012-06-01

    Full Text Available Background Infected leg ulcers are major health problems resulting in morbidity and disability and are usually chronic and refractory to antimicrobial treatment. Aims The present study is aimed at determining the bacteria involved in leg ulcers and their resistance patterns to commonly used antibiotics as well as to determine whether Aloe Vera has antibacterial activity against multi-drug resistant organisms and promotes wound healing. Method A total of 30 cases with leg ulcers infected with multi-drug resistant organisms were treated with topical aloe vera gel and 30 age and sex-matched controls were treated with topical antibiotics. Culture and sensitivity was done from the wounds on alternate days and the ulcer was clinically and microbiologically assessed after 10 days. The results were compiled and statistically analysed. Results Cultures of the study group who were using aloe vera dressings showed no growth by the fifth day in 10 (33.3% cases, seventh day in another 16 (53.3% and ninth day in two of the remaining four cases (6.7% while in two (6.7% cases there was no decrease in the bacterial count. This means that of the 30 cases, 28 showed no growth by the end of 11 days while two cases showed no decrease in bacterial count. Growth of bacteria in study group is decreased from 100% (30 cases to 6.7% (2 cases by day 11 with P

  1. Leg edema from intrathecal opiate infusions.

    Science.gov (United States)

    Aldrete, J A; Couto da Silva JM

    2000-01-01

    Despite the increasing popularity of intrathecal infusions to treat patients with long-term non-cancer-related pain, this therapy is not without serious side-effects. Five out of 23 patients who had intrathecal infusions of opiates for longer than 24 months developed leg and feet edema. As predisposing factors, cardiovascular disease, deep venous thrombosis, peripheral vascular disease, and venous stasis of the lower extremities were considered. Every patient who developed pedal and leg edema after the implantation of an infusion pump was also found to have leg edema and venous stasis prior to the time when the pump was inserted. This complication was severe enough to limit their physical activity, and to produce lymphedema, ulcerations and hyperpigmentation of the skin. Reduction of the edema occurred when the dose of the opiate was decreased, and in two cases in which the infusion was discontinued, there was almost complete resolution of the syndrome. It appears that the pre-existence of pedal edema and of venous stasis is a relative contraindication to the long-term intrathecal infusion of opiates in patients with chronic non-cancer pain. Copyright 2000 European Federation of Chapters of the International Association for the Study of Pain.

  2. Knee-extension-assist for knee-ankle-foot orthoses.

    Science.gov (United States)

    Spring, Alexander; Kofman, Jonathan; Lemaire, Edward

    2011-01-01

    Individuals with quadriceps muscle weakness often have difficulty generating the knee-extension moments required for common mobility tasks. A new device that provides a knee-extension moment was designed to help individuals perform sit-to-stand and stand-to-sit. The knee-extension-assist (KEA) was designed as a modular component to be incorporated into existing knee-ankle-foot-orthoses (KAFO). The KEA loads a set of springs as the knee flexes under bodyweight and returns the stored energy as an extension moment during knee extension. The springs can be locked in place at the end of flexion to prevent unwanted knee extension while seated. When the affected leg is unloaded, the device disengages, allowing free joint motion. A prototype KEA underwent mechanical testing and biomechanical evaluation on an able-bodied individual during sit-to-stand and stand-to-sit.

  3. Voluntary work organization in higher educational establishment: theory and practice

    Directory of Open Access Journals (Sweden)

    Sergey V. Polatayko

    2011-01-01

    Full Text Available The article analyses basic questions of voluntary work formation in higher educational establishment, its conceptual and legislative basis, defines basic directions of students agencies activities and forms of their participation in higher educational establishment activities.

  4. Respiratory inductance plethysmography is suitable for voluntary hyperventilation test.

    Science.gov (United States)

    Calabrese, Pascale; Besleaga, Tudor; Eberhard, André; Vovc, Victor; Baconnier, Pierre

    2007-01-01

    The aim of this work was to evaluate the goodness of fit of a signal issued of the respiratory inductance plethysmography (RIP) derivative to the airflow signal during rest, voluntary hyperventilation, and recovery. RIP derivative signal was filtered with an adjusted filter based on each subject airflow signal (pneumotachography). For each subject and for each condition (rest, voluntary hyperventilation, and recovery) comparisons were performed between the airflow signal and the RIP derivative signal filtered with an adjusted filter obtained either on rest signal or on the studied part of the signals (voluntary hyperventilation or recovery). Results show that the goodness of fit was : (1) higher than 90% at almost all comparisons (122 on 132), (2) not improved by applying an adjusted filter obtained on the studied part of the signals. These results suggest that RIP could be used for studying breathing during voluntary hyperventilation and recovery using adjusted filters obtained from comparison to airflow signal at rest.

  5. 78 FR 71476 - Authority for Voluntary Withholding on Other Payments

    Science.gov (United States)

    2013-11-29

    ...)(3) authorizes the Secretary to provide regulations for withholding from (A) remuneration for... AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Temporary regulations. SUMMARY: This document contains temporary regulations under the Internal Revenue Code (Code) relating to voluntary withholding...

  6. Improving Voluntary Environmental Management Programs: Facilitating Learning and Adaptation

    Science.gov (United States)

    Genskow, Kenneth D.; Wood, Danielle M.

    2011-05-01

    Environmental planners and managers face unique challenges understanding and documenting the effectiveness of programs that rely on voluntary actions by private landowners. Programs, such as those aimed at reducing nonpoint source pollution or improving habitat, intend to reach those goals by persuading landowners to adopt behaviors and management practices consistent with environmental restoration and protection. Our purpose with this paper is to identify barriers for improving voluntary environmental management programs and ways to overcome them. We first draw upon insights regarding data, learning, and adaptation from the adaptive management and performance management literatures, describing three key issues: overcoming information constraints, structural limitations, and organizational culture. Although these lessons are applicable to a variety of voluntary environmental management programs, we then present the issues in the context of on-going research for nonpoint source water quality pollution. We end the discussion by highlighting important elements for advancing voluntary program efforts.

  7. Do anti-embolism stockings fit our legs? Leg survey and data analysis.

    Science.gov (United States)

    Macintyre, Lisa; Kent, Kimberly; McPhee, Donna

    2013-07-01

    Anti-embolism stockings are commonly used worldwide to prevent the development of thrombosis in hospitalised patients. Patients are typically measured for, and fitted with, anti-embolism stockings during extended periods of non-ambulation. Anti-embolism stockings must critically fit the leg to achieve optimum blood flow and thus success of prophylaxis. Therefore, hospitals endeavour to maintain stock of anti-embolism stockings that fit the majority of their patients. The objective of this study was to establish whether popular styles/brands of anti-embolism stockings "fitted" the legs of convenience sampled volunteers. Volunteer's legs were measured at ankle, calf and thigh following guidance from British nurses and in accordance with brand instructions. Leg measurements were subsequently compared to the size charts of 10 anti-embolism stocking styles made by 4 different manufacturers. "Fit" is defined as a volunteer's leg measurements matching any stocking size in a range at all measurement points. Volunteers were measured in different settings around Scotland, including private homes, work places and shopping centres. A convenience sample of 471 volunteers (283 female, 188 male) were recruited on the basis of willingness to participate and being over 16 years old. Volunteers ranged from 17 years to 82 years old with an average age of 35. The 10 different styles of anti-embolism stockings, made by 4 different brands, examined for this paper had a size match coefficient ranging from 0% to 100% for our volunteer's legs. The size match coefficient is strongly influenced by the Brand's sizing policy. The proportion of legs that "fit" a particular brand of anti-embolism stockings can be increased through: (1) the reduction of the number of leg measurement points that need to be matched to the size chart of the stockings; (2) the use of open-ended size ranges; (3) the use of increased size range width and (4) the use of increased overlap between sizes. However, all but

  8. [Pentoxifylline medication within the scope of leg-ulcer therapy. Results of a field study using Trental 400].

    Science.gov (United States)

    Pemler, K; Penth, B; Adams, H J

    1979-06-07

    513 patients with chronic ulcers of the leg were treated with Trental 400 orally in addition to local therapy. Regarding the reduction of the symptoms: ulcer extension, coldness of the leg, paraesthesia, resting pain and improvement of walking distance, 215 patients were classified as considerably improved, 195 distinctly improved, 53 slightly improved and 44 unchanged. Four cases worsened, two cases could not be classified. The possibility of combining oral therapy with local treatment and surgical measures (skin-flaps) is shown in three case reports. Gastro-intestinal tolerance of Trental 400 was good, interactions with concomitantly administered drugs were not reported.

  9. A Case of Painless Legs and Moving Toes Syndrome in Parkinson’s Disease Responsive to Dopaminergic Therapy

    Directory of Open Access Journals (Sweden)

    Sumihiro Kawajiri

    2016-01-01

    Full Text Available Painless Legs and Moving Toes Syndrome (PoLMT is a rare movement disorder characterized by flexion, extension, abduction, adduction, and torsion of toes without pain. It is considered a variant of Painful Legs and Moving Toes Syndrome (PLMT, which is characterized by similar movements but with pain. Although neuropathy and several central nervous system (CNS involvements have been reported to be associated with PoLMT, the actual cause and mechanism remain unclear. Here we describe the first case of PoLMT in Parkinson’s Disease (PD, parallel to parkinsonism in severity, who demonstrated a good response to dopaminergic therapy.

  10. Assessing voluntary muscle activation with the twitch interpolation technique.

    Science.gov (United States)

    Shield, Anthony; Zhou, Shi

    2004-01-01

    The twitch interpolation technique is commonly employed to assess the completeness of skeletal muscle activation during voluntary contractions. Early applications of twitch interpolation suggested that healthy human subjects could fully activate most of the skeletal muscles to which the technique had been applied. More recently, however, highly sensitive twitch interpolation has revealed that even healthy adults routinely fail to fully activate a number of skeletal muscles despite apparently maximal effort. Unfortunately, some disagreement exists as to how the results of twitch interpolation should be employed to quantify voluntary activation. The negative linear relationship between evoked twitch force and voluntary force that has been observed by some researchers implies that voluntary activation can be quantified by scaling a single interpolated twitch to a control twitch evoked in relaxed muscle. Observations of non-linear evoked-voluntary force relationships have lead to the suggestion that the single interpolated twitch ratio can not accurately estimate voluntary activation. Instead, it has been proposed that muscle activation is better determined by extrapolating the relationship between evoked and voluntary force to provide an estimate of true maximum force. However, criticism of the single interpolated twitch ratio typically fails to take into account the reasons for the non-linearity of the evoked-voluntary force relationship. When these reasons are examined, it appears that most are even more challenging to the validity of extrapolation than they are to the linear equation. Furthermore, several factors that contribute to the observed non-linearity can be minimised or even eliminated with appropriate experimental technique. The detection of small activation deficits requires high resolution measurement of force and careful consideration of numerous experimental details such as the site of stimulation, stimulation intensity and the number of interpolated

  11. Effect of Renal Transplantation in Restless Legs Syndrome.

    Science.gov (United States)

    Kahvecioglu, Serdar; Yildiz, Demet; Buyukkoyuncu, Nilufer; Celik, Huseyin; Tufan, Fatih; Kılıç, Ahmet Kasım; Gul, Bulent; Yildiz, Abdulmecid

    2016-02-01

    Restless legs syndrome is a disorder in which patients have irresistible urge to move legs during rest. Restless legs syndrome seems to be common in end-stage renal disease. After a successful renal transplant, symptoms ameliorate with renal function improvement and restless legs syndrome is seen less in this population. Here, we aimed to investigate restless legs syndrome frequency and associated factors in renal transplant patients. In a cross-sectional study with 193 patients (116 hemodialysis patients, 45 transplant patients, and 32 controls), the presence of restless legs syndrome was assessed using the Restless Legs Syndrome Questionnaire. Medical history, demographic, and laboratory data were collected from the patients' medical records. Patients were questioned about the presence of restless legs syndrome using the Restless Legs Syndrome Questionnaire. Patients were evaluated with Beck Depression Scale for depression and Pittsburgh tests for sleep disturbances. While the rate of restless legs syndrome was similar between transplants and controls, it was significantly greater in hemodialysis patients. Hemodialysis patients and controls had similar depression scores that were higher compared with transplant patients. Pittsburgh score was similar in transplant patients and controls and significantly increased in the hemodialysis patients. The rate of insomnia was significantly higher in the hemodialysis patients compared with the other 2 groups. Logistic regression analysis revealed independent correlates of restless legs syndrome as insomnia, Beck depression score, and being on hemodialysis. Linear regression analysis showed that independent correlates of higher Pittsburgh score were higher depression score, higher age, and presence of restless legs syndrome. The prevalence of restless legs syndrome is significantly lower in transplant patients than it is in patients on maintenance dialysis. In renal transplant patients, restless legs syndrome frequency was

  12. What's new: Management of venous leg ulcers: Approach to venous leg ulcers.

    Science.gov (United States)

    Alavi, Afsaneh; Sibbald, R Gary; Phillips, Tania J; Miller, O Fred; Margolis, David J; Marston, William; Woo, Kevin; Romanelli, Marco; Kirsner, Robert S

    2016-04-01

    Leg ulcerations are a common problem, with an estimated prevalence of 1% to 2% in the adult population. Venous leg ulcers are primarily treated in outpatient settings and often are managed by dermatologists. Recent advances in the diagnosis and treatment of leg ulcers combined with available evidence-based data will provide an update on this topic. A systematized approach and the judicious use of expensive advanced therapeutics are critical. Specialized arterial and venous studies are most commonly noninvasive. The ankle brachial pressure index can be performed with a handheld Doppler unit at the bedside by most clinicians. The vascular laboratory results and duplex Doppler findings are used to identify segmental defects and potential operative candidates. Studies of the venous system can also predict a subset of patients who may benefit from surgery. Successful leg ulcer management requires an interdisciplinary team to make the correct diagnosis, assess the vascular supply, and identify other modifiable factors to optimize healing. The aim of this continuing medical education article is to provide an update on the management of venous leg ulcers. Part I is focused on the approach to venous ulcer diagnostic testing.

  13. LEG CONQUASATION CAUSED BY PETROL TILLER WITH OPEN LOWER LEG FRACTURE

    Directory of Open Access Journals (Sweden)

    Ivan Golubović

    2014-03-01

    Full Text Available We present a 71-year old patient admitted to Plastic and Reconstructive Surgery Clinic, Clinical Center Niš for the right leg conquasation. The patient was injured accidentally by a petrol tiller. On admission, both thigh and lower leg conquasation was observed with large wound on anteromedial thigh and one on medial side of the lower leg. Soft tissue and bones were covered with dirt and pieces of clothing. The wounds were thoroughly rinsed and dirt was removed followed by detailed debridement. After primary surgical treatment of the wound, open proximal lower leg fracture was stabilized with external skeletal fixation using two nails in the proximal and two nails in the distal fragment. Soft tissue defect was treated by plastic surgeon. The patient was administered anti-tetanus protection, antibiotic treatment and anticoagulant prophylaxis of deep vein thrombosis and pulmonary thromboembolism. Physical therapy was initiated subsequent to successful healing of the soft tissue wounds. External skeletal fixation was removed after three months for infection around the proximal nails and the treatment was contuinued using functional Sarmiento’s plaster imobilization leading to full recovery of open lower leg fracture.

  14. Restless Legs Syndrome and Leg Motor Restlessness in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Keisuke Suzuki

    2015-01-01

    Full Text Available Sleep disturbances are important nonmotor symptoms in Parkinson’s disease (PD that are associated with a negative impact on quality of life. Restless legs syndrome (RLS, which is characterized by an urge to move the legs accompanied by abnormal leg sensations, can coexist with PD, although the pathophysiology of these disorders appears to be different. RLS and PD both respond favorably to dopaminergic treatment, and several investigators have reported a significant relationship between RLS and PD. Sensory symptoms, pain, motor restlessness, akathisia, and the wearing-off phenomenon observed in PD should be differentiated from RLS. RLS in PD may be confounded by chronic dopaminergic treatment; thus, more studies are needed to investigate RLS in drug-naïve patients with PD. Recently, leg motor restlessness (LMR, which is characterized by an urge to move the legs that does not fulfill the diagnostic criteria for RLS, has been reported to be observed more frequently in de novo patients with PD than in age-matched healthy controls, suggesting that LMR may be a part of sensorimotor symptoms intrinsic to PD. In this paper, we provide an overview of RLS, LMR, and PD and of the relationships among these disorders.

  15. Voluntary reaction time and long-latency reflex modulation.

    Science.gov (United States)

    Forgaard, Christopher J; Franks, Ian M; Maslovat, Dana; Chin, Laurence; Chua, Romeo

    2015-12-01

    Stretching a muscle of the upper limb elicits short (M1) and long-latency (M2) reflexes. When the participant is instructed to actively compensate for a perturbation, M1 is usually unaffected and M2 increases in size and is followed by the voluntary response. It remains unclear if the observed increase in M2 is due to instruction-dependent gain modulation of the contributing reflex mechanism(s) or results from voluntary response superposition. The difficulty in delineating between these alternatives is due to the overlap between the voluntary response and the end of M2. The present study manipulated response accuracy and complexity to delay onset of the voluntary response and observed the corresponding influence on electromyographic activity during the M2 period. In all active conditions, M2 was larger compared with a passive condition where participants did not respond to the perturbation; moreover, these changes in M2 began early in the appearance of the response (∼ 50 ms), too early to be accounted for by voluntary overlap. Voluntary response latency influenced the latter portion of M2, with the largest activity seen when accuracy of limb position was not specified. However, when participants aimed for targets of different sizes or performed movements of various complexities, reaction time differences did not influence M2 period activity, suggesting voluntary activity was sufficiently delayed. Collectively, our results show that while a perturbation applied to the upper limbs can trigger a voluntary response at short latency (reflex gain modulation remains an important contributor to EMG changes during the M2 period. Copyright © 2015 the American Physiological Society.

  16. Voluntary "involuntary" commitment--the briar-patch syndrome.

    Science.gov (United States)

    Miller, R D

    1980-01-01

    Szasz and others have pointed out that many so-called voluntary admissions to mental hospitals have various elements of coercion involved, and are thus not truly voluntary. The author contends that the converse situation is also true, that many patients admitted under involuntary commitment papers arrange for their own commitments. Reasons for such choices are discussed in the context of a review of the literature and several case histories.

  17. Voluntary euthanasia under control? Further empirical evidence from The Netherlands.

    Science.gov (United States)

    Jochemsen, H; Keown, J

    1999-01-01

    Nineteen ninety-six saw the publication of a major Dutch survey into euthanasia in the Netherlands. This paper outlines the main statistical findings of this survey and considers whether it shows that voluntary euthanasia is under effective control in the Netherlands. The paper concludes that although there has been some improvement in compliance with procedural requirements, the practice of voluntary euthanasia remains beyond effective control. PMID:10070633

  18. Students' vocational choices and voluntary action: A 12-nation study

    OpenAIRE

    Haski-Leventhal, Debbie; Cnaan, Ram; Handy, Femida; Brudney, Jeffrey; Holmes, Kirsten; Hustinx, Lesley; Kang, ChulHee; Kassam, Meenaz; Meijs, Lucas; Ranade, Bhagyashree; Yamauchi, Naoto; Yeung, Anne Birgitta; Zrinscak, Sinisa

    2008-01-01

    textabstractPrevious research on student involvement suggested that business and engineering students manifest lowest rates of voluntary action. Similarly, it was thought that social science students are the most involved in voluntary action, with students of natural sciences and humanities in the middle. However, there were very few studies that empirically compared these assertions. Furthermore, these assertions were not investigated from cross-cultural perspectives. Based on a study of stu...

  19. The We and the I: The Logic of Voluntary Associations

    OpenAIRE

    Melnik, Ekaterina; Zimmermann, Jean-Benoît

    2015-01-01

    This paper sheds new light on the economic logic of voluntary associations and the relationship between individual contribution and collective action. The aims are twofold. Firstly, we seek to explain how "team reasoning" (Bacharach et al. 2006) can deeply change the functioning of voluntary associations (which are considered to produce a public good) when some or all of the individual members group together to make collective decisions about their involvement or contribution, rather than dec...

  20. Interaction of poststroke voluntary effort and functional neuromuscular electrical stimulation.

    Science.gov (United States)

    Makowski, Nathaniel; Knutson, Jayme; Chae, John; Crago, Patrick

    2013-01-01

    Functional electrical stimulation (FES) may be able to augment functional arm and hand movement after stroke. Poststroke neuroprostheses that incorporate voluntary effort and FES to produce the desired movement must consider how forces generated by voluntary effort and FES combine, even in the same muscle, in order to provide an appropriate level of stimulation to elicit the desired assistive force. The goal of this study was to determine whether the force produced by voluntary effort and FES add together independently of effort or whether the increment in force depends on the level of voluntary effort. Isometric force matching tasks were performed under different combinations of voluntary effort and FES. Participants reached a steady level of force, and while attempting to maintain a constant effort level, FES was applied to augment the force. Results indicate that the increment in force produced by FES decreases as the level of initial voluntary effort increases. Potential mechanisms causing the change in force output are proposed, but the relative contribution of each mechanism is unknown.

  1. Comparison of body-powered voluntary opening and voluntary closing prehensor for activities of daily life

    Directory of Open Access Journals (Sweden)

    Kelsey Berning

    2014-05-01

    Full Text Available Persons with an upper-limb amputation who use a body-powered prosthesis typically control the prehensor through contralateral shoulder movement, which is transmitted through a Bowden cable. Increased cable tension either opens or closes the prehensor; when tension is released, some passive element, such as a spring, returns the prehensor to the default state (closed or open. In this study, we used the Southampton Hand Assessment Procedure to examine functional differences between these two types of prehensors in 29 nondisabled subjects (who used a body-powered bypass prosthesis and 2 persons with unilateral transradial amputations (who used a conventional body-powered device. We also administered a survey to determine whether subjects preferred one prehensor or the other for specific tasks, with a long-term goal of assessing whether a prehensor that could switch between both modes would be advantageous. We found that using the voluntary closing prehensor was 1.3 s faster (p = 0.02 than using the voluntary opening prehensor, across tasks, and that there was consensus among subjects on which types of tasks they preferred to do with each prehensor type. Twenty-five subjects wanted a device that could switch between the two modes in order to perform particular tasks.

  2. Hedonic value of intentional action provides reinforcement for voluntary generation but not voluntary inhibition of action.

    Science.gov (United States)

    Parkinson, Jim; Haggard, Patrick

    2013-12-01

    Intentional inhibition refers to stopping oneself from performing an action at the last moment, a vital component of self-control. It has been suggested that intentional inhibition is associated with negative hedonic value, perhaps due to the frustration of cancelling an intended action. Here we investigate hedonic implications of the free choice to act or inhibit. Participants gave aesthetic ratings of arbitrary visual stimuli that immediately followed voluntary decisions to act or to inhibit action. We found that participants for whom decisions to act produced a strong positive hedonic value for the immediately following visual stimulus made more choices to act than those with weaker hedonic value for action. This finding is consistent with reinforcement learning of action decisions. However, participants who experienced inhibition as generating more positive hedonic value did not choose to inhibit more than other participants. Thus, voluntary inhibition of action did not act as reinforcement for future inhibitory behaviour. Our finding that inhibition of action lacks motivational capacity may explain why self-control is both difficult and limited.

  3. Comparison of body-powered voluntary opening and voluntary closing prehensor for activities of daily life.

    Science.gov (United States)

    Berning, Kelsey; Cohick, Sarah; Johnson, Reva; Miller, Laura Ann; Sensinger, Jonathon W

    2014-01-01

    Persons with an upper-limb amputation who use a body-powered prosthesis typically control the prehensor through contralateral shoulder movement, which is transmitted through a Bowden cable. Increased cable tension either opens or closes the prehensor; when tension is released, some passive element, such as a spring, returns the prehensor to the default state (closed or open). In this study, we used the Southampton Hand Assessment Procedure to examine functional differences between these two types of prehensors in 29 nondisabled subjects (who used a body-powered bypass prosthesis) and 2 persons with unilateral transradial amputations (who used a conventional body-powered device). We also administered a survey to determine whether subjects preferred one prehensor or the other for specific tasks, with a long-term goal of assessing whether a prehensor that could switch between both modes would be advantageous. We found that using the voluntary closing prehensor was 1.3 s faster (p = 0.02) than using the voluntary opening prehensor, across tasks, and that there was consensus among subjects on which types of tasks they preferred to do with each prehensor type. Twenty-five subjects wanted a device that could switch between the two modes in order to perform particular tasks.

  4. Voluntary control of human jaw stiffness.

    Science.gov (United States)

    Shiller, Douglas M; Houle, Guillaume; Ostry, David J

    2005-09-01

    Recent studies of human arm movement have suggested that the control of stiffness may be important both for maintaining stability and for achieving differences in movement accuracy. In the present study, we have examined the voluntary control of postural stiffness in 3D in the human jaw. The goal is to address the possible role of stiffness control in both stabilizing the jaw and in achieving the differential precision requirements of speech sounds. We previously showed that patterns of kinematic variability in speech are systematically related to the stiffness of the jaw. If the nervous system uses stiffness control as a means to regulate kinematic variation in speech, it should also be possible to show that subjects can voluntarily modify jaw stiffness. Using a robotic device, a series of force pulses was applied to the jaw to elicit changes in stiffness to resist displacement. Three orthogonal directions and three magnitudes of forces were tested. In all conditions, subjects increased the magnitude of jaw stiffness to resist the effects of the applied forces. Apart from the horizontal direction, greater increases in stiffness were observed when larger forces were applied. Moreover, subjects differentially increased jaw stiffness along a vertical axis to counteract disturbances in this direction. The observed changes in the magnitude of stiffness in different directions suggest an ability to control the pattern of stiffness of the jaw. The results are interpreted as evidence that jaw stiffness can be adjusted voluntarily, and thus may play a role in stabilizing the jaw and in controlling movement variation in the orofacial system.

  5. Cortical potentials associated with voluntary mandibular movements.

    Science.gov (United States)

    Yoshida, K; Kaji, R; Hamano, T; Kohara, N; Kimura, J; Shibasaki, H; Iizuka, T

    2000-07-01

    Movement-related cortical potentials (MRCPs) are negative potentials over the scalp, which gradually increase prior to voluntary movements, and might be applied to elucidate the cortical efferent function of the mandibular movements. We compared the MRCPs accompanying various mandibular movements to study the motor control mechanism underlying these movements. Electroencephalograms (EEGs) were recorded from 11 electrodes placed over the scalp (F3, Fz, F4, T3, C3, Cz, C4, T4, P3, Pz, and P4), according to the International 10-20 System, and electromyograms (EMGs) were obtained from surface electrodes over the masseter muscle and the anterior belly of the digastric muscle. Ten healthy subjects were requested to make brisk and self-paced mandibular movements in 4 different directions (mouth-opening and -closing, and left and right lateral movements). We obtained MRCPs by averaging the EEG, using the visually determined EMG onset as a trigger signal. In all the movements, a slowly increasing, bilaterally widespread negativity starting 1.5 to 2.0 sec before the EMG onset (Bereitschaftspotential, or BP proper) was observed, with the maximum over the vertex region. The negative slope (NS') occurred about 300 to 700 msec before the EMG onset. The cortical maps of BP/NS' (BP and NS' combined), immediately prior to the mouth-opening and closing, showed a symmetrical distribution, whereas that for the lateral movements showed a tendency of predominance over the hemisphere ipsilateral to the direction of the movement. BP/NS' amplitudes at the onset of movement differed significantly or tended to do so between open, close, and lateral movements, suggesting that MRCP recordings may thus provide a means to explore the role of the cerebral cortex in the control of mandibular movements.

  6. Voluntary organizations in development in South Asia.

    Science.gov (United States)

    Maloney, C

    1987-01-01

    The governments of South Asian countries have become aware of the substantial role that nongovernment organizations (NGOs) or voluntary agencies can play in rural development and other nation building activities. Although private agencies cannot substitute for government programs, there is general consensus that NGOs use development funds more efficiently and innovatively than government programs. NGOs in Bangladesh, India, and Pakistan exemplify the influence these organizations have on development in South Asia. The Lutheran World Service in Bangladesh, a foreign origin NGO, has branched out from its original aim of providing relief and war rehabilitation to give skills training and technical assistance to the poor. The Bangladesh Rural Advancement Committee, an indigenous NGO, works for the well-being and self-reliance of the landless poor, those with very small farms, and women. NGOs in Bangladesh have been especially innovative in developing methods to encourage self-help, such as local organization and credit, which are often combined with training in practical skills, literacy, nutrition, and family planning. Present NGO activity in India is dominated by the Gandhian tradition. There is a potential conflict between the philosophy of the NGO's in terms of building on the people's felt needs from the bottom up and the tendency of government agencies to want to plan for the people. In Pakistan, the concept of development-oriented NGOs is recent and not yet strong, although the government has adopted a policy of routing funds from government and from bilateral donor agencies through NGOs in 2 areas--family planning and women's welfare. The chief limitation of NGOs is their scope, meaning that the major burden of the development process rests on government agencies.

  7. Spontaneous locomotor activity in late-stage chicken embryos is modified by stretch of leg muscles.

    Science.gov (United States)

    Bradley, Nina S; Ryu, Young U; Yeseta, Marie C

    2014-03-15

    Chicks initiate bilateral alternating steps several days before hatching and adaptively walk within hours of hatching, but emergence of precocious walking skills is not well understood. One of our aims was to determine whether interactions between environment and movement experience prior to hatching are instrumental in establishing precocious motor skills. However, physiological evidence of proprioceptor development in the chick has yet to be established; thus, one goal of this study was to determine when in embryogenesis proprioception circuits can code changes in muscle length. A second goal was to determine whether proprioception circuits can modulate leg muscle activity during repetitive limb movements for stepping (RLMs). We hypothesized that proprioception circuits code changes in muscle length and/or tension, and modulate locomotor circuits producing RLMs in anticipation of adaptive locomotion at hatching. To this end, leg muscle activity and kinematics were recorded in embryos during normal posture and after fitting one ankle with a restraint that supported the limb in an atypical posture. We tested the hypotheses by comparing leg muscle activity during spontaneous RLMs in control posture and ankle extension restraint. The results indicated that proprioceptors detect changes in muscle length and/or muscle tension 3 days before hatching. Ankle extension restraint produced autogenic excitation of the ankle flexor and reciprocal inhibition of the ankle extensor. Restraint also modified knee extensor activity during RLMs 1 day before hatching. We consider the strengths and limitations of these results and propose that proprioception contributes to precocious locomotor development during the final 3 days before hatching.

  8. Relationship between hip and core strength and frontal plane alignment during a single leg squat.

    Science.gov (United States)

    Stickler, Laurie; Finley, Margaret; Gulgin, Heather

    2015-02-01

    The purpose of this study was to examine the relationship between frontal plane kinematics of the single leg squat and strength of the trunk and hip in females. Forty healthy females participated in this study. An isometric "make" test using a dynamometer was used to assess peak force normalized to body weight for hip abduction, hip extension, hip external rotation, and a sidelying plank test. Two-dimensional software was used to analyze the frontal plane projection angle (FPPA) and pelvic angle during a single leg squat to 60°. All 4 strength factors were significantly correlated with the FPPA, ranging from r = 0.396 to r = 0.466. During multiple regression analysis, hip abduction strength was the greatest predictor of the variation in FPPA at r(2) = 0.22, p = 0.002. Thus, hip abduction strength accounted for 22% of the variation in the FPPA during the single leg squat. The only strength factor demonstrating a significant correlation with the pelvic angle was hip extension strength (r = 0.550, p core musculature on the impact on the FPPA during a single squat, with focus on the hip abductors. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Leg movements during wakefulness in restless legs syndrome: time structure and relationships with periodic leg movements during sleep.

    Science.gov (United States)

    Ferri, Raffaele; Manconi, Mauro; Plazzi, Giuseppe; Bruni, Oliviero; Cosentino, Filomena I I; Ferini-Strambi, Luigi; Zucconi, Marco

    2012-05-01

    Approximately one third of patients with restless legs syndrome (RLS) also show periodic leg movements (PLM) during relaxed wake fulness (PLMW). In contrast with the large amount of data published on periodic leg movements during sleep (PLMS), PLMW have received less attention from the scientific community. The objective of this study was to evaluate the correlations/differences of time-structure and response to a dopamine-agonist between PLMW and PLMS in patients with RLS. Ninety idiopathic RLS patients and 28 controls were recruited. Subjects underwent clinical and neurophysiological evaluation, hematological screening, and one or two consecutive full-night polysomnographic studies. A subset of patients received 0.25mg of pramipexole or placebo before the second recording. Polysomnographic recordings were scored and LM activity was analyzed during sleep and during the epochs of wakefulness occurring during the first recording hour. RLS patients had higher LM activity during wakefulness than controls, but with a similar periodicity. Even if correlated, the ability of the PLMW index to predict the PLMS index decreased with increasing LM activity. Intermovement intervals during wakefulness showed one peak only at approximately 4s, gradually decreasing with increasing interval in both patients and controls. The effect of pramipexole was very limited and involved the small periodic portion of LM activity during wakefulness. PLMW index and PLMS index were correlated; however, the magnitude of this correlation was not sufficient to suggest that PLMW can be good predictors of PLMS. Short-interval LM activity during wakefulness and sleep might be linked to the severity of sleep disruption in RLS patients and the differences between their features obtained during wakefulness or sleep might be relevant for the diagnosis of sleep disturbances in RLS. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Profile of altered brain iron acquisition in restless legs syndrome

    Science.gov (United States)

    Ponnuru, Padmavathi; Wang, Xin-Sheng; Patton, Stephanie M.; Allen, Richard P.; Earley, Christopher J.

    2011-01-01

    Restless legs syndrome is a neurological disorder characterized by an urgency to move the legs during periods of rest. Data from a variety of sources provide a compelling argument that the amount of iron in the brain is lower in individuals with restless legs syndrome compared with neurologically normal individuals. Moreover, a significant percentage of patients with restless legs syndrome are responsive to intravenous iron therapy. The mechanism underlying the decreased iron concentrations in restless legs syndrome brains is unknown. We hypothesize that the source of the brain iron deficit is at the blood–brain interface. Thus we analysed the expression of iron management proteins in the epithelial cells of the choroid plexus and the brain microvasculature in post-mortem tissues. The choroid plexus, obtained at autopsy, from 18 neurologically normal controls and 14 individuals who had primary restless legs syndrome was subjected to histochemical staining for iron and immunostaining for iron management proteins. Iron and heavy chain ferritin staining was reduced in the epithelial cells of choroid plexus in restless legs syndrome. Divalent metal transporter, ferroportin, transferrin and its receptor were upregulated in the choroid plexus in restless legs syndrome. Microvessels were isolated from the motor cortex of 11 restless legs syndrome and 14 control brains obtained at autopsy and quantitative immunoblot analyses was performed. Expression of heavy chain ferritin, transferrin and its receptor in the microvessels from restless legs syndrome was significantly decreased compared with the controls but divalent metal protein 1, ferroportin, prohepcidin, mitochondrial ferritin and light-chain ferritin remained unchanged. The presence of an iron regulatory protein was demonstrated in the brain microvasculature and the activity of this protein is decreased in restless legs syndrome; a finding similar to our earlier report in neuromelanin cells from the substantia

  11. Profile of altered brain iron acquisition in restless legs syndrome.

    Science.gov (United States)

    Connor, James R; Ponnuru, Padmavathi; Wang, Xin-Sheng; Patton, Stephanie M; Allen, Richard P; Earley, Christopher J

    2011-04-01

    Restless legs syndrome is a neurological disorder characterized by an urgency to move the legs during periods of rest. Data from a variety of sources provide a compelling argument that the amount of iron in the brain is lower in individuals with restless legs syndrome compared with neurologically normal individuals. Moreover, a significant percentage of patients with restless legs syndrome are responsive to intravenous iron therapy. The mechanism underlying the decreased iron concentrations in restless legs syndrome brains is unknown. We hypothesize that the source of the brain iron deficit is at the blood-brain interface. Thus we analysed the expression of iron management proteins in the epithelial cells of the choroid plexus and the brain microvasculature in post-mortem tissues. The choroid plexus, obtained at autopsy, from 18 neurologically normal controls and 14 individuals who had primary restless legs syndrome was subjected to histochemical staining for iron and immunostaining for iron management proteins. Iron and heavy chain ferritin staining was reduced in the epithelial cells of choroid plexus in restless legs syndrome. Divalent metal transporter, ferroportin, transferrin and its receptor were upregulated in the choroid plexus in restless legs syndrome. Microvessels were isolated from the motor cortex of 11 restless legs syndrome and 14 control brains obtained at autopsy and quantitative immunoblot analyses was performed. Expression of heavy chain ferritin, transferrin and its receptor in the microvessels from restless legs syndrome was significantly decreased compared with the controls but divalent metal protein 1, ferroportin, prohepcidin, mitochondrial ferritin and light-chain ferritin remained unchanged. The presence of an iron regulatory protein was demonstrated in the brain microvasculature and the activity of this protein is decreased in restless legs syndrome; a finding similar to our earlier report in neuromelanin cells from the substantia nigra

  12. Actigraphic assessment of periodic leg movements in patients with restless legs syndrome.

    Science.gov (United States)

    Cippà, Maria A T; Baumann, Christian R; Siccoli, Massimiliano M; Bassetti, Claudio L; Poryazova, Rositsa; Werth, Esther

    2013-10-01

    The diagnosis of restless legs syndrome (RLS) relies upon diagnostic criteria which are based on history only, and dopaminergic treatment is not normally the first choice of treatment for all patients. It would be worthwhile to identify patients non-responsive to dopaminergic treatment beforehand, because they may suffer from a restless legs-like syndrome and may require alternative treatment. We included retrospectively 24 adult patients fulfilling the four essential criteria for restless legs and 12 age-matched healthy controls. They were investigated by ambulatory actigraphy from both legs over three nights, and patients started treatment with dopamine agonists after this diagnostic work-up. We examined 12 responders to dopaminergic treatment and 12 non-responders and studied the association between response to dopaminergic treatment and the periodic limb movement index (PLMI) as assessed with actigraphy. Demographic characteristics, excessive daytime sleepiness and fatigue at baseline were similar in all three groups. Baseline RLS severity was similar between responders and non-responders [International Restless Legs Severity Scale (IRLS): 25 ± 9 and 24 ± 8]. Group comparisons of PLMI before treatment initiation showed significant differences between the three groups. Post-hoc pairwise comparisons revealed that healthy controls had significantly lower PLMI (4.9 ± 4.5) than responders (29.3 ± 22.7) and non-responders (13.3 ± 11.2). Similarly, the PLMI in responders was lower than in non-responders. PLMI day-to-day variability did not differ between responders and non-responders and there was no correlation between treatment effect, as assessed by the decrease of the IRLS and baseline PLMI. Our retrospective study indicates that actigraphy to assess periodic limb movements may contribute to a better diagnosis of dopamine-responsive restless legs syndrome.

  13. The natural shock absorption of the leg spring.

    Science.gov (United States)

    Kim, Wangdo; João, Filipa; Tan, John; Mota, Patricia; Vleck, Veronica; Aguiar, Liliana; Veloso, Antonio

    2013-01-04

    When a human being runs, muscles, tendons, and ligaments together behave like a single linear spring. This "leg spring" can be described remarkably well by spring/mass models. Although leg-stiffness during running (and logically, therefore, in hopping) has been shown to be adjusted in line with the individual characteristics of the external contact surface, the relative contribution of each of the sub-components of the leg spring to the mechanics of running is unclear. We proposed the three-degree-of-freedom leg spring chain in a position of stable equilibrium under the action of the leg stiffness. If the leg spring receives a displacement in hopping, the forces will no longer equilibrate, but the system will be exposed to the action of a force on a leg spring chain. We thus have two corresponding sets of modes, one set being the mode about which the chain is displaced, the other set for the forces which are evoked in consequence of the displacement. We found that if the leg has been displaced from a position of equilibrium about one of harmonic modes, then a vibration about this harmonic mode evokes a system of forces in the leg spring which in its turn tends to produce a motion on the original harmonic mode, and thus produce oscillation about the same harmonic mode. Our results suggest that the desired harmonic mode can be explained in terms of the natural shock absorption ability of the leg.

  14. Leg stiffness of sprinters using running-specific prostheses

    Science.gov (United States)

    McGowan, Craig P.; Grabowski, Alena M.; McDermott, William J.; Herr, Hugh M.; Kram, Rodger

    2012-01-01

    Running-specific prostheses (RSF) are designed to replicate the spring-like nature of biological legs (bioL) during running. However, it is not clear how these devices affect whole leg stiffness characteristics or running dynamics over a range of speeds. We used a simple spring–mass model to examine running mechanics across a range of speeds, in unilateral and bilateral transtibial amputees and performance-matched controls. We found significant differences between the affected leg (AL) of unilateral amputees and both ALs of bilateral amputees compared with the bioL of non-amputees for nearly every variable measured. Leg stiffness remained constant or increased with speed in bioL, but decreased with speed in legs with RSPs. The decrease in leg stiffness in legs with RSPs was mainly owing to a combination of lower peak ground reaction forces and increased leg compression with increasing speeds. Leg stiffness is an important parameter affecting contact time and the force exerted on the ground. It is likely that the fixed stiffness of the prosthesis coupled with differences in the limb posture required to run with the prosthesis limits the ability to modulate whole leg stiffness and the ability to apply high vertical ground reaction forces during sprinting. PMID:22337629

  15. Relationship between Leg Mass, Leg Composition and Foot Velocity on Kicking Accuracy in Australian Football

    Science.gov (United States)

    Hart, Nicolas H.; Nimphius, Sophia; Spiteri, Tania; Cochrane, Jodie L.; Newton, Robert U.

    2016-01-01

    Kicking a ball accurately over a desired distance to an intended target is arguably the most important skill to acquire in Australian Football. Therefore, understanding the potential mechanisms which underpin kicking accuracy is warranted. The aim of this study was to examine the relationship between leg mass, leg composition and foot velocity on kicking accuracy in Australian Football. Thirty-one Australian Footballers (n = 31; age: 22.1 ± 2.8 years; height: 1.81 ± 0.07 m; weight: 85.1 ± 13.0 kg; BMI: 25.9 ± 3.2) each performed ten drop punt kicks over twenty metres to a player target. Athletes were separated into accurate (n = 15) and inaccurate (n = 16) kicking groups. Leg mass characteristics were assessed using whole body DXA scans. Foot velocity was determined using a ten-camera optoelectronic, three-dimensional motion capture system. Interactions between leg mass and foot velocity evident within accurate kickers only (r = -0.670 to -0.701). Relative lean mass was positively correlated with kicking accuracy (r = 0.631), while no relationship between foot velocity and kicking accuracy was evident in isolation (r = -0.047 to -0.083). Given the evident importance of lean mass, and its interaction with foot velocity for accurate kickers; future research should explore speed-accuracy, impulse-variability, limb co-ordination and foot-ball interaction constructs in kicking using controlled with-in subject studies to examine the effects of resistance training and skill acquisition programs on the development of kicking accuracy. Key points Accurate kickers expressed a very strong inverse relationship between leg mass and foot velocity. Inaccurate kickers were unable to replicate this, with greater volatility in their performance, indicating an ability of accurate kickers to mediate foot velocity to compensate for leg mass in order to deliver the ball over the required distance. Accurate kickers exhibited larger quantities of relative lean mass and lower

  16. Multiple-step model-experiment matching allows precise definition of dynamical leg parameters in human running.

    Science.gov (United States)

    Ludwig, C; Grimmer, S; Seyfarth, A; Maus, H-M

    2012-09-21

    The spring-loaded inverted pendulum (SLIP) model is a well established model for describing bouncy gaits like human running. The notion of spring-like leg behavior has led many researchers to compute the corresponding parameters, predominantly stiffness, in various experimental setups and in various ways. However, different methods yield different results, making the comparison between studies difficult. Further, a model simulation with experimentally obtained leg parameters typically results in comparatively large differences between model and experimental center of mass trajectories. Here, we pursue the opposite approach which is calculating model parameters that allow reproduction of an experimental sequence of steps. In addition, to capture energy fluctuations, an extension of the SLIP (ESLIP) is required and presented. The excellent match of the models with the experiment validates the description of human running by the SLIP with the obtained parameters which we hence call dynamical leg parameters.

  17. Long-term paired associative stimulation can restore voluntary control over paralyzed muscles in incomplete chronic spinal cord injury patients.

    Science.gov (United States)

    Shulga, Anastasia; Lioumis, Pantelis; Zubareva, Aleksandra; Brandstack, Nina; Kuusela, Linda; Kirveskari, Erika; Savolainen, Sarianna; Ylinen, Aarne; Mäkelä, Jyrki P

    2016-01-01

    Emerging therapeutic strategies for spinal cord injury aim at sparing or restoring at least part of the corticospinal tract at the acute stage. Hence, approaches that strengthen the weak connections that are spared or restored are crucial. Transient plastic changes in the human corticospinal tract can be induced through paired associative stimulation, a noninvasive technique in which transcranial magnetic brain stimulation is synchronized with electrical peripheral nerve stimulation. A single paired associative stimulation session can induce transient plasticity in spinal cord injury patients. It is not known whether paired associative stimulation can strengthen neuronal connections persistently and have therapeutic effects that are clinically relevant. We recruited two patients with motor-incomplete chronic (one para- and one tetraplegic) spinal cord injuries. The patients received paired associative stimulation for 20-24 weeks. The paraplegic patient, previously paralyzed below the knee level, regained plantarflexion and dorsiflexion of the ankles of both legs. The tetraplegic patient regained grasping ability. The newly acquired voluntary movements could be performed by the patients in the absence of stimulation and for at least 1 month after the last stimulation session. In this unblinded proof-of-principle demonstration in two subjects, long-term paired associative stimulation induced persistent and clinically relevant strengthening of neural connections and restored voluntary movement in previously paralyzed muscles. Further study is needed to confirm whether long-term paired associative stimulation can be used in rehabilitation after spinal cord injury by itself and, possibly, in combination with other therapeutic strategies.

  18. A Kinematic Analysis of the Jumping Front-Leg Axe-Kick in Taekwondo

    Directory of Open Access Journals (Sweden)

    Emanuel Preuschl, Michaela Hassmann, Arnold Baca

    2016-03-01

    Full Text Available The jumping front-leg axe-kick is a valid attacking and counterattacking technique in Taekwondo competition (Streif, 1993. Yet, the existing literature on this technique is sparse (Kloiber et al., 2009. Therefore, the goal of this study was to determine parameters contributing significantly to maximum linear speed of the foot at impact. Parameters are timing of segment and joint angular velocity characteristics and segment lengths of the kicking leg. Moreover, we were interested in the prevalence of proximal-to-distal-sequencing. Three-dimensional kinematics of the kicks of 22 male Taekwondo-athletes (age: 23.3 ± 5.3 years were recorded via a motion capturing system (Vicon Motion Systems Limited, Oxford, UK. The participants performed maximum effort kicks onto a rack-held kicking pad. Only the kick with the highest impact velocity was analysed, as it was assumed to represent the individual’s best performance. Significant Pearson correlations to impact velocity were found for pelvis tilt angular displacement (r = 0.468, p < 0.05 and for hip extension angular velocity (r = -0.446, p < 0.05 and for the timing of the minima of pelvis tilt velocity (r = -0.426, p < 0.05 and knee flexion velocity (r = -0.480, p < 0.05. Backward step linear regression analysis suggests a model consisting of three predictor variables: pelvis tilt angular displacement, hip flexion velocity at target contact and timing of pelvic tilt angular velocity minimum (adjusted R2 = 0.524. Results of Chi-Squared tests show that neither for the leg-raising period (χ2 = 2.909 of the technique, nor for the leg-lowering period a pattern of proximal-to-distal sequencing is prevalent (χ2 = 0.727. From the results we conclude that the jumping front-leg axe-kick does not follow a proximal-to-distal pattern. Raising the leg early in the technique and apprehending the upper body to be leant back during the leg-lowering period seems to be beneficial for high impact velocity. Furthermore

  19. D-ribose benefits restless legs syndrome.

    Science.gov (United States)

    Shecterle, Linda; Kasubick, Robert; St Cyr, John

    2008-11-01

    Restless legs syndrome is a neurological disorder characterized by unpleasant sensations and pain, predominantly in the lower extremities while at rest, accompanied by an uncontrollable urge for movement for relief. We report on two affected male individuals, a father and son, ages 71 and 47, from a family in which three generations carry the diagnosis. To evaluate any potential benefit of D-ribose in this condition, each individual orally consumed 5-g doses of D-ribose daily at different trial stages. Each stage lasted 3 weeks with a 2-week washout period between stages. The initial stage involved a single 5 gm dose of D-ribose consumed at breakfast. Throughout the second stage, D-ribose was taken at breakfast and lunch. In the third stage, D-ribose was taken at all meals, breakfast, lunch, and dinner. Diaries by the subjects pertaining to their documentation and severity of restless legs syndrome symptoms was compiled. During the initial stage both men reported a general feeling of more energy and less fatigue, most notably after exercise, without any significant changes in their symptoms. With the increase in the daily dose of D-ribose, in the second stage, their leg twitching and the feeling to move during the day was reduced for 1 subject, and rarely present in the other. Both still experienced the unpleasant sensations during the night. However, during the final stage, a further increase in the daily dose of D-ribose eliminated their daily symptoms and the symptoms at night were of a lesser degree and had a later occurrence. Both men reported that D-ribose did not totally eliminate their discomfort, but the severity and onset of symptoms affecting their quality of life was substantially improved with D-ribose without any adverse reactions.

  20. [Bow legged adjectives in ancient literature].

    Science.gov (United States)

    Simon, Frantisek; Steger, Florian

    2011-01-01

    This article addresses the issue of capturing the medical entity called 'curved legs' in a terminologically exact way. In so doing, it refers to the long-lasting process of differentiation of exact nuances of meaning in Ancient Greek and Latin. In the chronological perusal of ancient Greek literature, it becomes evident that the various adjectives employed are often vague when looking at non-medical literature. By contrast, in the Hippocratic corpus these terms are for the first time annotated with explanations intended to lead to a more precise understanding of the described deformity. Further attempts of differentiation can be found in the writings of Galen, who not only distinguishes between outward and inward curvatures, but also between deformities of the thigh and lower leg as well as between pathological and natural curvatures. Latin literature also provides a series of adjectives that were initially often used in the meaning of 'curved' but it was not until Celsus that these were differentiated with respect to the type and direction of the curvature. When comparing Greek and Latin adjectives, it turns out that though the Latin term blaesus can be traced back etymologically to the Greek word beta lambda alpha iota sigma ó zeta, the meaning of beta lambda alpha iota sigma ó zeta does not fully correspond to that of the Latin word. It is not before the later common transliteration of Greek words that this adjective took on the meaning of beta lambda alpha iota sigma ó zeta; however, this was finally lost again. In summary, the article concludes that exact word meanings in ancient literature are often unclear and precise ascriptions of meanings are inconsistent. In the case of "curved legs," this has led to misunderstandings regarding the respective types and directions of the curvature.

  1. Opt-out HIV testing in prison: informed and voluntary?

    Science.gov (United States)

    Rosen, David L; Golin, Carol E; Grodensky, Catherine A; May, Jeanine; Bowling, J Michael; DeVellis, Robert F; White, Becky L; Wohl, David A

    2015-01-01

    HIV testing in prison settings has been identified as an important mechanism to detect cases among high-risk, underserved populations. Several public health organizations recommend that testing across health-care settings, including prisons, be delivered in an opt-out manner. However, implementation of opt-out testing within prisons may pose challenges in delivering testing that is informed and understood to be voluntary. In a large state prison system with a policy of voluntary opt-out HIV testing, we randomly sampled adult prisoners in each of seven intake prisons within two weeks after their opportunity to be HIV tested. We surveyed prisoners' perception of HIV testing as voluntary or mandatory and used multivariable statistical models to identify factors associated with their perception. We also linked survey responses to lab records to determine if prisoners' test status (tested or not) matched their desired and perceived test status. Thirty-eight percent (359/936) perceived testing as voluntary. The perception that testing was mandatory was positively associated with age less than 25 years (adjusted relative risk [aRR]: 1.45, 95% confidence interval [CI]: 1.24, 1.71) and preference that testing be mandatory (aRR: 1.81, 95% CI: 1.41, 2.31) but negatively associated with entry into one of the intake prisons (aRR: 0.41 95% CI: 0.27, 0.63). Eighty-nine percent of prisoners wanted to be tested, 85% were tested according to their wishes, and 82% correctly understood whether or not they were tested. Most prisoners wanted to be HIV tested and were aware that they had been tested, but less than 40% understood testing to be voluntary. Prisoners' understanding of the voluntary nature of testing varied by intake prison and by a few individual-level factors. Testing procedures should ensure that opt-out testing is informed and understood to be voluntary by prisoners and other vulnerable populations.

  2. Journal of Agricultural Extension

    African Journals Online (AJOL)

    Mission Statement The mission of the "Journal of Agricultural Extension" is to publish ... diffusion and adoption of innovations; extension communication models and ... Socio-Economic Determinants of Cocoyam Farmer's Strategies for Climate ...

  3. Effects of unilateral leg muscle fatigue on balance control in perturbed and unperturbed gait in healthy elderly.

    Science.gov (United States)

    Toebes, Marcel J P; Hoozemans, Marco J M; Dekker, Joost; van Dieën, Jaap H

    2014-01-01

    This study assessed effects of unilateral leg muscle fatigue (ULMF) on balance control in gait during the stance and swing phases of the fatigued leg in healthy elderly, to test the assumption that leg muscle strength limits balance control during the stance-phase. Ten subjects (aged 63.4, SD 5.5 years) walked on a treadmill in 4 conditions: unperturbed unfatigued, unperturbed fatigued, perturbed unfatigued, and perturbed fatigued. The perturbations were lateral trunk pulls just before contralateral heel contact. ULMF was evoked by unilateral squat exercise until task failure. Isometric knee extension strength was measured to verify the presence of muscle fatigue. Between-stride standard deviations and Lyapunov exponents of trunk kinematics were used as indicators of balance control. Required perturbation force and the deviation of trunk kinematics from unperturbed gait were used to assess perturbation responses. Knee extension strength decreased considerably (17.3% SD 8.6%) as a result ULMF. ULMF did not affect steady-state gait balance. Less force was required to perturb subjects when the fatigued leg was in the stance-phase compared to the swing-phase. Subjects showed a faster return to the unperturbed gait pattern in the fatigued than in the unfatigued condition, after perturbations in swing and stance of the fatigued leg. The results of this study are not in line with the hypothesized effects of leg muscle fatigue on balance in gait. The healthy elderly subjects were able to cope with substantial ULMF during steady-state gait and demonstrated faster balance recovery after laterally directed mechanical perturbations in the fatigued than in the unfatigued condition.

  4. Refractory leg ulcers associated with Klinefelter syndrome.

    Science.gov (United States)

    Yabuno, Yuto; Tosa, Mamiko; Iwakiri, Itaru; Nomoto, Shunichi; Kaneko, Mayuko; Kuwahara, Kousuke; Hyakusoku, Hiko; Murakami, Masahiro

    2015-01-01

    We present a man with refractory leg ulcers, bilateral varicosis of the lower extremities, and Buerger disease. Autoimmune work-up was negative. However, chromosome analysis showed Klinefelter syndrome (48 XXY). Ulcerative lesions of the lower extremities are a complication of Klinefelter syndrome. To date, the pathogenesis of ulcers in Klinefelter syndrome has not been clarified, but several factors, such as abnormalities of fibrinolysis and prothrombotic states, might be involved. Our present case emphasizes the importance of considering Klinefelter syndrome in the differential diagnosis of a male patient with nonhealing ulcers of the lower extremities.

  5. Leg ulcer in lepromatous leprosy - Case report*

    Science.gov (United States)

    Fernandes, Tania Rita Moreno de Oliveira; dos Santos, Talita Suzany Siqueira; Lopes, Ramon Rodrigues de Macedo

    2016-01-01

    In Brazil, leprosy is a widespread infectious and contagious disease. Clinicians and specialists view leprosy broadly as a systemic infection, since, in its manifestations, it mimics many conditions, such as rheumatic, vascular, ENT, neurological and dermatological diseases. There are few studies that characterize the factors associated with ulcers in leprosy. These injuries should be prevented and treated promptly to avoid serious problems like secondary infections, sepsis, carcinomatous degeneration and amputations. We describe a patient with ulcers on his legs, involving late diagnosis of lepromatous leprosy. PMID:27828650

  6. Coordinated intelligent adaptive control of legged robots

    Science.gov (United States)

    McLauchlan, Lifford; Mehrübeoğlu, Mehrübe

    2006-05-01

    In planetary or hazardous environment exploration, there will be unforseen environmental circumstances which can not be planned. To overcome telerobotic control issues due to communication delays, autonomous robot control becomes necessary. Autonomously controlled landers and instrumentation can be used in exploration, such as lunar and martian missions. However, wheeled robots have difficulty in exploring uneven terrain; thus, legged robots can be used in such situations. This research develops intelligent and adaptive control of mobile robots to perform functions such as environmental exploration in coordination and obstacle avoidance. The coordinated control is demonstrated in simulations.

  7. Painful legs and moving toes syndrome

    Directory of Open Access Journals (Sweden)

    Qiu-ying Ma

    2015-10-01

    Full Text Available Painful legs and moving toes syndrome (PLMT is a rare movement disorder with low diagnostic rate, which is characterized by lower limb pain with involuntary movements of feet or toes. Etiology and pathogenesis of this disease is still unclear. Patients have different clinical manifestations, so the diagnosis is difficult. Treatment methods for PLMT are numerous, but so far the treatment of this disease is still a major challenge for clinicians. Further research is still needed to guide clinical work. DOI: 10.3969/j.issn.1672-6731.2015.10.013

  8. Restless Legs Syndrome After Single Low Dose Quetiapine Administration.

    Science.gov (United States)

    Soyata, Ahmet Z; Celebi, Fahri; Yargc, Lutfi I

    2016-01-01

    Restless legs syndrome is an underdiagnosed sensori-motor disorder and psychotropic drugs are one of the main secondary causes of the illness. The most common psychotropic agents that cause restless legs syndrome are antidepressants; however, antipsychotics have also been reported to induce restless legs syndrome. The prevalence, vulnerability factors and the underlying mechanism of antipsychotic-induced restless legs syndrome are unclear. A possible explanation is that dopaminergic blockade is the main precipitator of the syndrome. Quetiapine-induced restless legs syndrome is another point of interest because of its low binding to D2 receptors. We herein report the case of a restless legs syndrome that emerged after a single low dose quetiapine administration.

  9. Mechanical Engineering of Leg Joints of Anthropomorphic Robot

    Directory of Open Access Journals (Sweden)

    Pavluk Nikita

    2016-01-01

    Full Text Available The problem of design engineering of anthropomorphic robot legs is considered. An overview of the existing anthropomorphic robots and an analysis of servomechanisms and bearing parts involved in the assembly of robot legs are presented. We propose an option for constructing the legs of the robot Antares under development. A two-motor layout, used in the knee, ensures higher joint power along with independent interaction with the neighboring upper and lower leg joints when bending. To reduce the electrical load on the main battery of the robot, the upper legs are provided with a mounting pad for additional batteries powering servos. Direct control of the servos is also carried out through the sub-controllers, responsible for all 6 engines installed in the articular joints of the robot legs.

  10. Symmetry Analysis of Thermoelectric Energy Converters with Inhomogeneous Legs

    Science.gov (United States)

    Korzhuev, M. A.

    2010-09-01

    Symmetry analysis has been applied to thermoelectric energy converters [thermoelectric generators (TEG), coolers (TEC), and heaters (TEH)] with inhomogeneous legs. The features of the crystallographic symmetry of thermoelectric materials and the symmetry of legs, thermocouples, and modules are studied. The effect of symmetry on the figure of merit Z of thermoelectric energy converters is considered. A general rule for proper placement of legs in thermoelectric converters is developed. A modified tetratomic classification for thermoelectric energy converters with inhomogeneous legs (TEGa, TEGb, TEC, and TEH) is proposed. An increase in Z for thermoelectric energy converters with inhomogeneous legs is due to the bulk thermoelectric effect. An increase in Z gives the reduction of irreversible processes in the modules (Joule heating and thermal conductivity), accompanying breaking of the symmetry of the legs. It is found that violations of the symmetry requirements can lead to significant energy losses in converters.

  11. Reconstruction of an external hemipelvectomy defect with a two-stage fillet of leg-free flap.

    Science.gov (United States)

    Boehmler, James H; Francis, Stacey H; Grawe, Roxanne K; Mayerson, Joel L

    2010-05-01

    The defect created by external hemipelvectomy for bone and soft tissue tumor resection is a challenge to reconstruct because of the exposure of bone, neurovascular structures, and peritoneal contents, particularly in the setting of previous radiotherapy. In a nonsalvageable limb with extensive tumor involvement and radiation damage, a free fillet of leg flap can be used to provide the necessary large volume of tissue for reconstruction without donor site morbidity. Because of the lengthy operative time for the hemipelvectomy procedure, the fillet of leg flap may be subject to long ischemia time and a subsequently compromised outcome. A two-stage fillet of leg flap for a hemipelvectomy defect was performed with two goals: to decrease ischemia time and to allow the necessary resuscitation of the patient between operative stages. Stage one was dissection of a lower fillet of leg flap, transfer and anastomosis to the contralateral femoral vessels, and temporary inset in the groin. The patient and flap were observed in the intensive care unit for several days. The patient returned to the operating room 3 days later for staged external hemipelvectomy and inset of the viable fillet of leg flap. Throughout follow-up, the reconstructive results and functional outcome were excellent.

  12. Stable bipedal walking with a swing-leg protraction strategy.

    Science.gov (United States)

    Bhounsule, Pranav A; Zamani, Ali

    2017-01-25

    In bipedal locomotion, swing-leg protraction and retraction refer to the forward and backward motion, respectively, of the swing-leg before touchdown. Past studies have shown that swing-leg retraction strategy can lead to stable walking. We show that swing-leg protraction can also lead to stable walking. We use a simple 2D model of passive dynamic walking but with the addition of an actuator between the legs. We use the actuator to do full correction of the disturbance in a single step (a one-step dead-beat control). Specifically, for a given limit cycle we perturb the velocity at mid-stance. Then, we determine the foot placement strategy that allows the walker to return to the limit cycle in a single step. For a given limit cycle, we find that there is swing-leg protraction at shallow slopes and swing-leg retraction at steep slopes. As the limit cycle speed increases, the swing-leg protraction region increases. On close examination, we observe that the choice of swing-leg strategy is based on two opposing effects that determine the time from mid-stance to touchdown: the walker speed at mid-stance and the adjustment in the step length for one-step dead-beat control. When the walker speed dominates, the swing-leg retracts but when the step length dominates, the swing-leg protracts. This result suggests that swing-leg strategy for stable walking depends on the model parameters, the terrain, and the stability measure used for control. This novel finding has a clear implication in the development of controllers for robots, exoskeletons, and prosthetics and to understand stability in human gaits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Leg stiffness of sprinters using running-specific prostheses

    OpenAIRE

    McGowan, Craig P.; Grabowski, Alena M.; McDermott, William J.; Herr, Hugh M.; Kram, Rodger

    2012-01-01

    Running-specific prostheses (RSF) are designed to replicate the spring-like nature of biological legs (bioL) during running. However, it is not clear how these devices affect whole leg stiffness characteristics or running dynamics over a range of speeds. We used a simple spring–mass model to examine running mechanics across a range of speeds, in unilateral and bilateral transtibial amputees and performance-matched controls. We found significant differences between the affected leg (AL) of uni...

  14. Redefining RECs: Additionality in the voluntary Renewable Energy Certificate market

    Science.gov (United States)

    Gillenwater, Michael Wayne

    In the United States, electricity consumers are told that they can "buy" electricity from renewable energy projects, versus fossil fuel-fired facilities, through participation in a voluntary green power program. The marketing messages communicate to consumers that their participation and premium payments for a green label will cause additional renewable energy generation and thereby allow them to claim they consume electricity that is absent pollution as well as reduce pollutant emissions. Renewable Energy Certificates (RECs) and wind energy are the basis for the majority of the voluntary green power market in the United States. This dissertation addresses the question: Do project developers respond to the voluntary REC market in the United States by altering their decisions to invest in wind turbines? This question is investigated by modeling and probabilistically quantifying the effect of the voluntary REC market on a representative wind power investor in the United States using data from formal expert elicitations of active participants in the industry. It is further explored by comparing the distribution of a sample of wind power projects supplying the voluntary green power market in the United States against an economic viability model that incorporates geographic factors. This dissertation contributes the first quantitative analysis of the effect of the voluntary REC market on project investment. It is found that 1) RECs should be not treated as equivalent to emission offset credits, 2) there is no clearly credible role for voluntary market RECs in emissions trading markets without dramatic restructuring of one or both markets and the environmental commodities they trade, and 3) the use of RECs in entity-level GHG emissions accounting (i.e., "carbon footprinting") leads to double counting of emissions and therefore is not justified. The impotence of the voluntary REC market was, at least in part, due to the small magnitude of the REC price signal and lack of

  15. Market Motivations for Voluntary Carbon Disclosure in Real Estate Industry

    Science.gov (United States)

    Ufere, Kalu Joseph; Alias, Buang; Godwin Uche, Aliagha

    2016-07-01

    Climate change mitigation in developing economies is a balancing act, between economic development and environmental sustainability. The need for market friendly determinants for low carbon economy, without compromising economic development is of essence. The aim of the study is to determine market friendly factors, which motivates voluntary carbon information disclosure, in the real estate industry. The study modeled economic factor with three variables and financial market factor with three variables against voluntary carbon information disclosure in the real estate industry. Structural equation modeling was used for the modeling and content analysis was used to collect data on the level of voluntary carbon information disclosure, from 2013 annual reports of 126 real estate sector companies listed in the Kuala Lumpur Stock Exchange (KLSE). The model achieved a good fit, and was acceptable prediction. The results show that financial market factor has a significant predictive influence on voluntary carbon disclosure. The application of the result is that financial market factor is has a significantly positive influence on companies’ willingness to make voluntary carbon disclosure in the real estate industry. The result may be limited to the real estate industry that is highly leveraged on syndicated fund.

  16. Lower leg electrical impedance after distal bypass surgery

    DEFF Research Database (Denmark)

    Belanger, G K; Bolbjerg, M L; Heegaard, N H

    1998-01-01

    Electrical impedance was determined in 13 patients following distal bypass surgery to evaluate lower leg oedema as reflected by its circumference. Tissue injury was assessed by the plasma concentration of muscle enzymes. After surgery, the volume of the control lower leg increased from 1250 (816...... of troponin I (n = 8). In conclusion, tissue injury was reflected by increases in muscle enzymes in plasma. We found an inverse correlation between lower leg electrical impedance and volume, but the deviation in electrical impedance was approximately twice that of the leg volume. Electrical impedance appears...

  17. Protection against high intravascular pressure in giraffe legs

    DEFF Research Database (Denmark)

    Petersen, Karin K; Hørlyck, Arne; Østergaard, Kristine Hovkjær

    2013-01-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination....... All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure....... revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along...

  18. Passive mechanical properties of legs from running insects.

    Science.gov (United States)

    Dudek, Daniel M; Full, Robert J

    2006-04-01

    While the dynamics of running arthropods have been modeled as a spring-mass system, no such structures have been discovered that store and return energy during bouncing. The hindleg of the cockroach Blaberus discoidalis is a good candidate for a passive, vertical leg spring because its vertically oriented joint axes of rotation limit the possibility of active movements and contributions of muscle properties. We oscillated passive legs while measuring force to determine the leg's dynamic, mechanical properties. The relative dimensionless stiffness of an individual cockroach leg was equal to that estimated for a single leg of a biped or quadruped. Leg resilience ranged from 60 to 75%, affording the possibility that the leg could function as a spring to store and return the mechanical energy required to lift and accelerate the center of mass. Because hysteresis was independent of oscillation frequency, we rejected the use of a Voigt model - a simple spring in parallel with a viscous damper. A hysteretic damping model fit the cockroach leg force-displacement data over a wide range of frequencies and displacement using just two parameters. Rather than simply acting as a spring to minimize energy, we hypothesize that legs must manage both energy storage and absorption for rapid running to be most effective.

  19. Tennis leg: mechanism of injury and radiographic presentation.

    Science.gov (United States)

    Pacheco, Rafael A; Stock, Harlan

    2013-08-01

    As summer is upon us, we thought a discussion of tennis leg would be beneficial to our fellow clinicians. Tennis leg is a relatively common clinical condition, classically manifesting as acute, sports-related pain in the mid-calf. First described in 1883, the pathogenesis has been debated--tennis leg was first attributed to rupture of the plantaris tendon, though more recent investigations have implicated rupture of the medial head of the gastrocnemius at its myotendinous junction. For simplicity, many authors use the term tennis leg to describe all such acute muscle injuries in the superficial calf.

  20. Contribution of non-extensor muscles of the leg to maximal-effort countermovement jumping

    Directory of Open Access Journals (Sweden)

    Yoshioka Shinsuke

    2005-09-01

    Full Text Available Abstract Background The purpose of this study was to determine the effects of non-extensor muscles of the leg (i.e., muscles whose primary function is not leg extension on the kinematics and kinetics of human maximal-effort countermovement jumping. Although it is difficult to address this type of question through experimental procedures, the methodology of computer simulation can be a powerful tool. Methods A skeletal model that has nine rigid body segments and twenty degrees of freedom was developed. Two sets of muscle models were attached to this skeletal model: all (most of major muscles in the leg ("All Muscles" model and major extensor muscles in the leg (i.e., muscles whose primary function is leg extension; "Extensors Only" model. Neural activation input signal was represented by a series of step functions with a step duration of 0.05 s. Simulations were started from an identical upright standing posture. The optimal pattern of the activation input signal was searched through extensive random-search numerical optimization with a goal of maximizing the height reached by the mass centre of the body after jumping up. Results The simulated kinematics was almost two-dimensional, suggesting the validity of two-dimensional analyses when evaluating net mechanical outputs around the joints using inverse dynamics. A greater jumping height was obtained for the "All Muscles" model (0.386 m than for the "Extensors Only" model (0.301 m. For the "All Muscles" model, flexor muscles developed force in the beginning of the countermovement. For the "All Muscles" model, the sum of the work outputs from non-extensor muscles was 47.0 J, which was 13% of the total amount (359.9 J. The quantitative distribution of the work outputs from individual muscles was markedly different between these two models. Conclusion It was suggested that the contribution of non-extensor muscles in maximal-effort countermovement jumping is substantial. The use of a computer

  1. Compression Stockings for Treating Venous Leg Ulcers

    Directory of Open Access Journals (Sweden)

    J. P. Benigni

    2013-01-01

    Full Text Available Background. In order to treat venous leg ulcers, it is recommended to use high pressure compression (30–40 mmHg at the ankle. Compression stockings which are not operator dependant could be the best option because of their pressure control. However 30–40 mmHg compression stockings are often hard to put on. Putting two lower pressure compression stockings over each other could be a good therapeutic alternative. Objectives. To compare the in vitro pressures given by the manufacturers of 2 antiulcer kits with the in vivo interface pressures measured in healthy subjects and to evaluate the stiffness and friction indices from those kits based on the interface pressure in order to assess their clinical properties. Material and Methods. Using a Kikuhime pressure device, interface pressure was measured in 12 healthy subjects at the reference point B1. One stiffness index (Static Stiffness Index (SSI and a friction index have been calculated. Results. Mediven Ulcer kit gets the recommended pressures whereas Jobst’s Ulcer Care kit does not for treating a venous leg ulcer. Jobst’s Ulcer Care transmits entirely the pressure in relation to a friction index close to 1. Conclusion. This antiulcer kit study underlines that in vivo and in vitro pressures can be different (Jobst’s Ulcer Care kit and Mediven Ulcer kit. In order not to lose pressure, it is important to take into account the friction index when superimposing two stockings.

  2. Lower leg musculoskeletal geometry and sprint performance.

    Science.gov (United States)

    Karamanidis, Kiros; Albracht, Kirsten; Braunstein, Bjoern; Moreno Catala, Maria; Goldmann, Jan-Peter; Brüggemann, Gert-Peter

    2011-05-01

    The purpose of this study was to investigate whether sprint performance is related to lower leg musculoskeletal geometry within a homogeneous group of highly trained 100-m sprinters. Using a cluster analysis, eighteen male sprinters were divided into two groups based on their personal best (fast: N=11, 10.30±0.07s; slow: N=7, 10.70±0.08s). Calf muscular fascicle arrangement and Achilles tendon moment arms (calculated by the gradient of tendon excursion versus ankle joint angle) were analyzed for each athlete using ultrasonography. Achilles tendon moment arm, foot and ankle skeletal geometry, fascicle arrangement as well as the ratio of fascicle length to Achilles tendon moment arm showed no significant (p>0.05) correlation with sprint performance, nor were there any differences in the analyzed musculoskeletal parameters between the fast and slow sprinter group. Our findings provide evidence that differences in sprint ability in world-class athletes are not a result of differences in the geometrical design of the lower leg even when considering both skeletal and muscular components.

  3. Restless legs syndrome in hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Shahram Rafie

    2016-01-01

    Full Text Available Restless legs syndrome (RLS is a neurological disorder characterized by uncomfortable sensation of paresthesia in legs that subsequently causes involuntary and continuous movement of the lower limbs, especially at rest. Its prevalence in hemodialysis is more than that in the general population. Different risk factors have been suggested for RLS. We studied the prevalence and risk factors of RLS in 137 hemodialysis patients followed up at our center. The patients completed at least three months on dialysis and fulfilled four criteria for the diagnosis of RLS. We compared the patients with and without RLS, and the odds ratios (ORs were estimated by the logistic regression models. The prevalence of RLS was 36.5% in the study patients. Among the variables, diabetes was the only predicting factor for the development of RLS. The diabetic patients may be afflicted with RLS 2.25 times more than the non-diabetics. Women developed severe RLS 5.23 times more than men. Neurodegeneration, decrease in dopamine level, higher total oxidant status, and neuropathy in diabetic patients may explain the RLS symptoms.

  4. Migraine and restless legs syndrome: current perspectives

    Directory of Open Access Journals (Sweden)

    Ferreira KS

    2015-12-01

    Full Text Available Karen dos Santos Ferreira, Fabíola Dach, Alan L Eckeli, José Geraldo SpecialiDepartment of Neurosciences and Behavioral Sciences, Division of Neurology, University Hospital, Medical School of Ribeirao Preto, University of São Paulo, São Paulo, BrazilAbstract: The relationship between migraine and restless legs syndrome (RLS has been described in the literature for some years, based on clinical findings and pathophysiological considerations. There are some possible factors relating migraine and RLS. Both are diseases involving the central nervous system, the two diseases seem to share a dopaminergic mechanism, and it is also believed that they may share a genetic origin. At present, doctors who work with these two diseases should be encouraged not to simply investigate the simultaneous presence of both, but should also apply a treatment better adapted to this possibility. Research should be directed at some still unanswered questions for a better understanding of the association between migraine and RLS.Keywords: migraine, restless legs syndrome, physiopathology, comorbidities

  5. [RESTLESS LEGS SYNDROME--WILLIS-EKBOM DISEASE].

    Science.gov (United States)

    Ruppert, Élisabeth; Bataillard, Marc; Bourgin, Patrice

    2015-09-01

    Restless legs syndrome (RLS) is a sensorimotor disorder with a high prevalence (10% in Caucasian populations). It is a purely clinical diagnosis characterized by an urge to move the lower limbs usually accompanied or caused by unpleasant sensations in the legs with an improvement in symptoms with movement. These sensations occur during inactivity or at rest and worsen in the evening or at night. RLS may not only impact the quality of life for an individual, but may also increase mortality. Disease markers such as genetic predispositions have been identified, as well as reduced iron stores with altered intracerebral iron homeostasis and dopaminergic dysfunction. Medication is often necessary in severe forms, with low doses of dopaminergic agonists being the first-line of treatment. The use of α2δ ligands is an alternative. Finally benzodiazepines and opioid medications can be effective in refractory cases. In less severe forms of RLS, a non-pharmacological approach is usually sufficient with avoidance of stimulants and correction of contributing factors.

  6. Restless Legs Syndrome with Current Diagnostic Criteria

    Directory of Open Access Journals (Sweden)

    Meral Bilgilisoy Filiz

    2015-08-01

    Full Text Available Restless legs syndrome (RLS, also known as Willis-Ekbom disease, is a chronic movement disorder, characterized by an urge to move legs usually accompanied by uncomfortable sensations and sleep disorders. The prevalence of the syndrome ranges from 1% to 15% in the general population, and about 2% during childhood. RLS is the most common movement disorder in pregnancy. However RLS still remains underdiagnosed probably due to lack of accurate information about the disease. Family history is positive in 50-70% of the primary RLS patients. The secondary form of the syndrome is associated with iron deficiency, renal failure, pregnancy, diabetes mellitus and many rheumatologic disorders. Secondary forms generally manifest at older ages and have a rapid progression with a poorer prognosis. The pathophysiology of RLS is focused on the dopaminergic system, reduced central nervous system iron levels and genetic linkages. Diagnosis is based on clinical features and the diagnostic criteria suggested by International RLS Study Group. Secondary causes must be carefully investigated before the treatment. In mild forms of the disease non-pharmacologic therapies might be useful, while in moderate or severe forms of the disease generally pharmacologic therapies such as dopamine agonists, anticonvulsants, opioids and benzodiazepines are required. (Turkish Journal of Osteoporosis 2015;21: 87-95

  7. Restless legs syndrome in hemodialysis patients.

    Science.gov (United States)

    Rafie, Shahram; Jafari, Majid; Azizi, Mostafa; Bahadoram, Mohammad; Jafari, Shima

    2016-03-01

    Restless legs syndrome (RLS) is a neurological disorder characterized by uncomfortable sensation of paresthesia in legs that subsequently causes involuntary and continuous movement of the lower limbs, especially at rest. Its prevalence in hemodialysis is more than that in the general population. Different risk factors have been suggested for RLS. We studied the prevalence and risk factors of RLS in 137 hemodialysis patients followed up at our center. The patients completed at least three months on dialysis and fulfilled four criteria for the diagnosis of RLS. We compared the patients with and without RLS, and the odds ratios (ORs) were estimated by the logistic regression models. The prevalence of RLS was 36.5% in the study patients. Among the variables, diabetes was the only predicting factor for the development of RLS. The diabetic patients may be afflicted with RLS 2.25 times more than the non-diabetics. Women developed severe RLS 5.23 times more than men. Neurodegeneration, decrease in dopamine level, higher total oxidant status, and neuropathy in diabetic patients may explain the RLS symptoms.

  8. Designing a Competency-Based New County Extension Personnel Training Program: A Novel Approach

    Science.gov (United States)

    Brodeur, Cheri Winton; Higgins, Cynthia; Galindo-Gonzalez, Sebastian; Craig, Diane D.; Haile, Tyann

    2011-01-01

    Voluntary county personnel turnover occurs for a multitude of reasons, including the lack of job satisfaction, organizational commitment, and job embeddedness and lack of proper training. Loss of personnel can be costly both economically and in terms of human capital. Retention of Extension professionals can be improved through proper training or…

  9. 75 FR 52542 - Extension of Agency Information Collection Activity Under OMB Review: Department of Homeland...

    Science.gov (United States)

    2010-08-26

    ... Management and Budget (OMB) control number 1652-0044, to OMB for review and approval of an extension of the... submission of identifying and travel experience information by individuals requesting redress through the... involves a voluntary customer satisfaction survey to identify areas for program improvement. The...

  10. Oxygenation and EMG in the proximal and distal vastus lateralis during submaximal isometric knee extension

    DEFF Research Database (Denmark)

    Crenshaw, Albert G.; Bronee, Lars; Krag, Ida

    2010-01-01

    /or (2) fatigue development. Nine males performed 2-min sustained isometric knee extensions at 15% and 30% maximum voluntary contraction during which oxygenation and EMG were recorded simultaneously from proximal and distal locations of the vastus lateralis muscle. Near infrared spectroscopy variables...

  11. Muscle Damage following Maximal Eccentric Knee Extensions in Males and Females.

    Directory of Open Access Journals (Sweden)

    K M Hicks

    Full Text Available To investigate whether there is a sex difference in exercise induced muscle damage.Vastus Lateralis and patella tendon properties were measured in males and females using ultrasonography. During maximal voluntary eccentric knee extensions (12 reps x 6 sets, Vastus Lateralis fascicle lengthening and maximal voluntary eccentric knee extensions torque were recorded every 10° of knee joint angle (20-90°. Isometric torque, Creatine Kinase and muscle soreness were measured pre, post, 48, 96 and 168 hours post damage as markers of exercise induced muscle damage.Patella tendon stiffness and Vastus Lateralis fascicle lengthening were significantly higher in males compared to females (p0.05. Creatine Kinase levels post exercise induced muscle damage were higher in males compared to females (p<0.05, and remained higher when maximal voluntary eccentric knee extension torque, relative to estimated quadriceps anatomical cross sectional area, was taken as a covariate (p<0.05.Based on isometric torque loss, there is no sex difference in exercise induced muscle damage. The higher Creatine Kinase in males could not be explained by differences in maximal voluntary eccentric knee extension torque, Vastus Lateralis fascicle lengthening and patella tendon stiffness. Further research is required to understand the significant sex differences in Creatine Kinase levels following exercise induced muscle damage.

  12. RAPID KNEE-EXTENSIONS TO INCREASE QUADRICEPS MUSCLE ACTIVITY IN PATIENTS WITH TOTAL KNEE ARTHROPLASTY

    DEFF Research Database (Denmark)

    Husted, Rasmus Skov; Wilquin, Lousia; Jakobsen, Thomas Linding

    2017-01-01

    BACKGROUND: Inhibition of the quadriceps muscle and reduced knee-extension strength is common shortly following total knee arthroplasty (weeks to months), due to reduced voluntary activation of the quadriceps muscle. In healthy subjects, strength training with heavy loads is known to increase ago...

  13. Rapid knee-extensions to increase quadriceps muscle activity in patients with total knee arthroplasty

    DEFF Research Database (Denmark)

    Husted, Rasmus Skov; Wilquin, Lousia; Jakobsen, Thomas Linding

    2017-01-01

    BACKGROUND: Inhibition of the quadriceps muscle and reduced knee-extension strength is common shortly following total knee arthroplasty (weeks to months), due to reduced voluntary activation of the quadriceps muscle. In healthy subjects, strength training with heavy loads is known to increase...... agonist muscle activity, especially if the exercise is conducted using rapid muscle contractions. PURPOSE: The purpose of this study was to examine if patients with total knee arthroplasty could perform rapid knee-extensions using a 10 RM load four to eight weeks after surgery, and the degree to which...... rapid knee-extensions were associated with greater voluntary quadriceps muscle activity during an experimental strength training session, compared to that elicited using slow knee-extensions. STUDY DESIGN: A randomized cross-over study. METHODS: Twenty-four patients (age 66.5) 4-8 weeks post total knee...

  14. Investigational approaches to therapies for restless legs syndrome.

    Science.gov (United States)

    de Biase, Stefano; Merlino, Giovanni; Lorenzut, Simone; Valente, Mariarosaria; Gigli, Gian Luigi

    2014-06-01

    Restless Legs Syndrome (RLS) is a common neurological disorder that impairs nocturnal rest, causing decreased alertness, depressed mood, reduced job performance and poor quality of life. In patients affected by severe RLS, pharmacological treatment is mandatory. The present review is based on an extensive Internet and PubMed search from 1994 - 2014. It focuses on drugs currently in development for the treatment of RLS. The drugs currently available for treating RLS do not always allow the patient to obtain a dose capable of controlling the symptoms, particularly in the long term. There is still the need for effective and well-tolerated new drugs. Monoamine oxidase B inhibitors could be good candidates for the initial treatment of RLS, sparing stronger dopaminergic agents for later stages of the disease. Oxycodone-naloxone has demonstrated a significant and sustained effect on patients with severe RLS inadequately controlled with first-line drugs; it could be used as a long-term treatment option in severe cases of RLS for which alternative satisfactory drug regimens are unavailable. There is a paucity of data comparing medications in head-to-head trials to determine their relative effectiveness and adverse event profiles. Furthermore, there is also a need for further studies that evaluate nondopaminergic agonists and combination therapies for treating RLS.

  15. Sensory signals of unloading in one leg follow stance onset in another leg: transfer of load and emergent coordination in cockroach walking.

    Science.gov (United States)

    Zill, Sasha N; Keller, Bridget R; Duke, Elizabeth R

    2009-05-01

    The transfer of load from one leg to another is an essential component in walking, but sense organs that signal this process have rarely been identified. We used high-speed digital imaging and neurophysiological recordings to characterize activities of tibial campaniform sensilla, receptors that detect forces via cuticular strains, in the middle legs of cockroaches during walking. Previous studies demonstrated that the distal tibial sensilla discharge when body load is suddenly decreased in freely standing animals. Sensory recordings during walking showed that distal receptors in the middle leg fired an intense burst near the end of the stance phase. We tested the hypothesis that initiation of distal firing resulted from the action of other legs entering stance. Analysis of leg movements in slow walking showed that sensory bursts in the middle leg closely followed stance onset of the ipsilateral hind leg while the ipsilateral front leg entered stance earlier in phase. Similar phases of leg movement were found in slow walking in experiments in which animals had no implanted recording wires. Those studies also demonstrated that the opposite middle leg entered stance earlier in phase. Measurements of leg positions in walking showed that the hind leg tarsus was placed closest to the middle leg, in keeping with a "targeting" strategy. Triggering of distal bursts in the middle leg by mechanical action of the hind leg could facilitate the onset of swing in the middle leg through local reflex effects and contribute to emergent coordination of leg movements in metachronal gaits.

  16. Neurons controlling voluntary vocalization in the macaque ventral premotor cortex.

    Directory of Open Access Journals (Sweden)

    Gino Coudé

    Full Text Available The voluntary control of phonation is a crucial achievement in the evolution of speech. In humans, ventral premotor cortex (PMv and Broca's area are known to be involved in voluntary phonation. In contrast, no neurophysiological data are available about the role of the oro-facial sector of nonhuman primates PMv in this function. In order to address this issue, we recorded PMv neurons from two monkeys trained to emit coo-calls. Results showed that a population of motor neurons specifically fire during vocalization. About two thirds of them discharged before sound onset, while the remaining were time-locked with it. The response of vocalization-selective neurons was present only during conditioned (voluntary but not spontaneous (emotional sound emission. These data suggest that the control of vocal production exerted by PMv neurons constitutes a newly emerging property in the monkey lineage, shedding light on the evolution of phonation-based communication from a nonhuman primate species.

  17. Suicide and voluntary active euthanasia: why the difference in attitude?

    Science.gov (United States)

    Beech, I

    1995-06-01

    It appears that the attitudes of health professionals differ towards suicide and voluntary active euthanasia. An acceptance of, if not an agreement with, voluntary active euthanasia exists, while there is a general consensus that suicide should be prevented. This paper searches for a working definition of suicide, to discover ethical reasons for the negative value that suicide assumes, and also to provide a term of reference when comparing suicide with euthanasia. On arriving at a working definition of suicide, it is compared with voluntary active euthanasia. An analysis of utilitarian and deontological considerations is provided and proves to be inconclusive with respect to the ethical principles informing the attitudes of professionals. Therefore, a search for other influences is attempted; this indicates that psychological influences inform attitudes to a greater degree than ethical principles.

  18. Propensity for Voluntary Travel Behavior Changes: An Experimental Analysis

    DEFF Research Database (Denmark)

    Meloni, Italo; Sanjust, Benedetta; Sottile, Eleonora;

    2013-01-01

    implementation, which consisted of providing car users with a personalized travel plan after the first week of observation (before) and using the second week to monitoring the post-behavior (after). These data have then been used to estimate a Mixed Logit for the choice to use a personal vehicle or a light metro......In this paper we analyze individual propensity to voluntary travel behavior change combining concepts from theory of change with the methodologies deriving from behavioral models. In particular, following the theory of voluntary changes, we set up a two-week panel survey including soft measure......; and a Multinomial Logit for the decision to change behavior. Results from both models show the relevance of providing information about available alternatives to individuals while promoting voluntary travel behavioral change....

  19. Klinefelter's syndrome presenting with leg ulcers.

    Science.gov (United States)

    De Morentin, Helena Martinez; Dodiuk-Gad, Roni P; Brenner, Sarah

    2004-01-01

    A 54-year-old man of Persian origin presented to our department with a 1-year history of ulcers on the right leg that had been unresponsive to numerous topical treatments, accompanied by lymphedema of the right leg. Medical history included hypergonadotropic hypogonadism, which had not been further investigated. He was treated for 20 years with testosterone IM once monthly, which he stopped a year before the current hospitalization for unclear reasons. The patient reported no congenital lymphedema. Physical examination revealed two deep skin ulcers (Figure 1) on the right leg measuring 10 cm in diameter with raised irregular inflammatory borders and a boggy, necrotic base discharging a purulent hemorrhagic exudate. Bilateral leg pitting edema and right lymphangitis with lymphadenitis were noted. He had low head hair implantment, sparse hair on the body and head, hyperpigmentation on both legs, onychodystrophia of the toenails (mainly the large toe and less prominent on the other toes), which was atrophic lichen-planus-like in appearance and needed no trimming (Figure 2), normal hand nails, oral thrush, and angular cheilitis. Other physical findings were gynecomastia, pectus excavatum, small and firm testicles, long extremities, asymmetrical goiter, systolic murmur 2/6 in left sternal border, and slow and inappropriate behavior. The patient's temperature on admission was 39 degrees C. Blood cultures were negative for bacterial growth. Results of laboratory investigations included hemoglobin (11.2 g/dL), hematocrit (26.8%), normal mean corpuscular volume and mean corpuscular hemoglobin volume, and red blood cell distribution width (16%). Blood smear showed spherocytes, slight hypochromia, anisocytosis, macrocytosis, and microcytosis. Blood chemistry values were taken for iron (4 micro g/dL [normal range 40-150 micro g/dL]), transferrin (193 mg/dL [normal range 220-400 mg/dL]), ferritin (1128 ng/mL [normal range 14-160 ng/mL]), transferrin saturation (1.5% [normal

  20. Final voluntary release assessment/corrective action report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-12

    The US Department of Energy, Carlsbad Area Office (DOE-CAO) has completed a voluntary release assessment sampling program at selected Solid Waste Management Units (SWMUs) at the Waste Isolation Pilot Plant (WIPP). This Voluntary Release Assessment/Corrective Action (RA/CA) report has been prepared for final submittal to the Environmental protection Agency (EPA) Region 6, Hazardous Waste Management Division and the New Mexico Environment Department (NMED) Hazardous and Radioactive Materials Bureau to describe the results of voluntary release assessment sampling and proposed corrective actions at the SWMU sites. The Voluntary RA/CA Program is intended to be the first phase in implementing the Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) and corrective action process at the WIPP. Data generated as part of this sampling program are intended to update the RCRA Facility Assessment (RFA) for the WIPP (Assessment of Solid Waste Management Units at the Waste Isolation Pilot Plant), NMED/DOE/AIP 94/1. This Final Voluntary RA/CA Report documents the results of release assessment sampling at 11 SWMUs identified in the RFA. With this submittal, DOE formally requests a No Further Action determination for these SWMUs. Additionally, this report provides information to support DOE`s request for No Further Action at the Brinderson and Construction landfill SWMUs, and to support DOE`s request for approval of proposed corrective actions at three other SWMUs (the Badger Unit Drill Pad, the Cotton Baby Drill Pad, and the DOE-1 Drill Pad). This information is provided to document the results of the Voluntary RA/CA activities submitted to the EPA and NMED in August 1995.

  1. VOLUNTARY DISCLOSURE OF CASH FLOWS INFORMATION AND COMPANY'S CHARACTERISTICS: EVIDENCE FROM THE CROATIAN CAPITAL MARKET

    Directory of Open Access Journals (Sweden)

    Željana Aljinović Barać

    2012-12-01

    Full Text Available This paper focuses on the voluntary disclosure of cash flows information of Croatian large companies whose shares are listed on the Zagreb Stock Exchange, with the aim to identify characteristics of companies that provide extensive disclosures. In order to conduct the research and test the likelihood that company publicly announces wealth of information about cash flows, three groups of company’s features are defined as variables: accounting data, capital market information and company’s qualitative characteristics. Verification of empirical evidence was provided through the sample of Croatian listed companies using logistic regression analysis. Obtained results indicate that despite the desire of the regulatory authorities that capital market investors receive all relevant information, companies voluntarily disclose information about cash flows very rarely. Those companies are young (i.e. their shares are listed on an organized securities market for a short time and profitable, with growing net income and growing cash flow from operating activities and usually use indirect method for operating cash flow report. The provision of features of Croatian companies that voluntary disclose cash flow information can be found as contribution of our research, because this topic in a cases of macro-oriented accounting system economies, i.e. bank oriented economies with emerging capital market is still unexplored.

  2. Voluntary vs directed siting -- or somewhere in-between?

    Energy Technology Data Exchange (ETDEWEB)

    Peelle, E.B.

    1994-04-01

    Waste siting gridlock in the United States and Canada has led to experimentation with voluntary and hybrid or ``mixed mode`` siting. We review nuclear and hazardous waste voluntary siting (VS) results for selected cases in the U.S, and Canada. Findings indicate that VS is not a panacea, but that current siting efforts are inadequate tests of its potential. We suggest trials of improved VS protocols and more effort on hybrid approaches in which the developer chooses the site but is required to reach agreement on conditions with local stakeholders. Mixed mode siting may be better suited to the US context and its three-tiered governmental system.

  3. The voluntary control of facial action units in adults.

    Science.gov (United States)

    Gosselin, Pierre; Perron, Mélanie; Beaupré, Martin

    2010-04-01

    We investigated adults' voluntary control of 20 facial action units theoretically associated with 6 basic emotions (happiness, fear, anger, surprise, sadness, and disgust). Twenty young adults were shown video excerpts of facial action units and asked to reproduce them as accurately as possible. Facial Action Coding System (FACS; Ekman & Friesen, 1978a) coding of the facial productions showed that young adults succeeded in activating 18 of the 20 target actions units, although they often coactivated other action units. Voluntary control was clearly better for some action units than for others, with a pattern of differences between action units consistent with previous work in children and adolescents. Copyright 2010 APA, all rights reserved.

  4. Market Brief: Status of the Voluntary Renewable Energy Certificate Market (2011 Data)

    Energy Technology Data Exchange (ETDEWEB)

    Heeter, J.; Armstrong, P.; Bird, L.

    2012-09-01

    This report documents the status and trends of U.S. 'voluntary' markets -- those in which consumers and institutions purchase renewable energy to match their electricity needs on a voluntary basis. Voluntary REC markets continue to exhibit growth and spur renewable energy development. Voluntary green power markets provide an additional revenue stream for renewable energy projects and raise consumer awareness of the benefits of renewable energy. Although a full estimate of the size of the voluntary market is not available for 2011, this review uses indicative metrics to capture 2011 voluntary market trends.

  5. Market Brief. Status of the Voluntary Renewable Energy Certificate Market (2011 Data)

    Energy Technology Data Exchange (ETDEWEB)

    Heeter, Jenny [National Renewable Energy Lab. (NREL), Golden, CO (United States); Armstrong, Philip [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bird, Lori [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2012-09-01

    This report documents the status and trends of U.S. 'voluntary' markets -- those in which consumers and institutions purchase renewable energy to match their electricity needs on a voluntary basis. Voluntary REC markets continue to exhibit growth and spur renewable energy development. Voluntary green power markets provide an additional revenue stream for renewable energy projects and raise consumer awareness of the benefits of renewable energy. Although a full estimate of the size of the voluntary market is not available for 2011, this review uses indicative metrics to capture 2011 voluntary market trends.

  6. Plyometric training improves voluntary activation and strength during isometric, concentric and eccentric contractions.

    Science.gov (United States)

    Behrens, Martin; Mau-Moeller, Anett; Mueller, Karoline; Heise, Sandra; Gube, Martin; Beuster, Nico; Herlyn, Philipp K E; Fischer, Dagmar-C; Bruhn, Sven

    2016-02-01

    This study investigated effects of plyometric training (6 weeks, 3 sessions/week) on maximum voluntary contraction (MVC) strength and neural activation of the knee extensors during isometric, concentric and eccentric contractions. Twenty-seven participants were randomly assigned to the intervention or control group. Maximum voluntary torques (MVT) during the different types of contraction were measured at 110° knee flexion (180°=full extension). The interpolated twitch technique was applied at the same knee joint angle during isometric, concentric and eccentric contractions to measure voluntary activation. In addition, normalized root mean square of the EMG signal at MVT was calculated. The twitch torque signal induced by electrical nerve stimulation at rest was used to evaluate training-related changes at the muscle level. In addition, jump height in countermovement jump was measured. After training, MVT increased by 20Nm (95% CI: 5-36Nm, P=0.012), 24Nm (95% CI: 9-40Nm, P=0.004) and 27Nm (95% CI: 7-48Nm, P=0.013) for isometric, concentric and eccentric MVCs compared to controls, respectively. The strength enhancements were associated with increases in voluntary activation during isometric, concentric and eccentric MVCs by 7.8% (95% CI: 1.8-13.9%, P=0.013), 7.0% (95% CI: 0.4-13.5%, P=0.039) and 8.6% (95% CI: 3.0-14.2%, P=0.005), respectively. Changes in the twitch torque signal of the resting muscle, induced by supramaximal electrical stimulation of the femoral nerve, were not observed, indicating no alterations at the muscle level, whereas jump height was increased. Given the fact that the training exercises consisted of eccentric muscle actions followed by concentric contractions, it is in particular relevant that the plyometric training increased MVC strength and neural activation of the quadriceps muscle regardless of the contraction mode. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  7. Type Safe Extensible Programming

    Science.gov (United States)

    Chae, Wonseok

    2009-10-01

    Software products evolve over time. Sometimes they evolve by adding new features, and sometimes by either fixing bugs or replacing outdated implementations with new ones. When software engineers fail to anticipate such evolution during development, they will eventually be forced to re-architect or re-build from scratch. Therefore, it has been common practice to prepare for changes so that software products are extensible over their lifetimes. However, making software extensible is challenging because it is difficult to anticipate successive changes and to provide adequate abstraction mechanisms over potential changes. Such extensibility mechanisms, furthermore, should not compromise any existing functionality during extension. Software engineers would benefit from a tool that provides a way to add extensions in a reliable way. It is natural to expect programming languages to serve this role. Extensible programming is one effort to address these issues. In this thesis, we present type safe extensible programming using the MLPolyR language. MLPolyR is an ML-like functional language whose type system provides type-safe extensibility mechanisms at several levels. After presenting the language, we will show how these extensibility mechanisms can be put to good use in the context of product line engineering. Product line engineering is an emerging software engineering paradigm that aims to manage variations, which originate from successive changes in software.

  8. Torque-wrench extension

    Science.gov (United States)

    Peterson, D. H.

    1981-01-01

    Torque-wrench extension makes it easy to install and remove fasteners that are beyond reach of typical wrenches or are located in narrow spaces that prevent full travel of wrench handle. At same time, tool reads applied torque accurately. Wrench drive system, for torques up to 125 inch-pounds, uses 2 standard drive-socket extensions in aluminum frame. Extensions are connected to bevel gear that turns another bevel gear. Gears produce 1:1 turn ratio through 90 degree translation of axis of rotation. Output bevel has short extension that is used to attach 1/4-inch drive socket.

  9. Treatment of sickle cell leg ulcers with pentoxifylline.

    Science.gov (United States)

    Frost, M L; Treadwell, P

    1990-06-01

    A 58-year-old black man with leg ulcers of 43 years duration responded to pentoxifylline 400 mg tid in 8 months. The ability of pentoxifylline to increase erythrocyte flexibility and decrease blood viscosity was the basis for our use of this agent. Oral pentoxifylline may be a useful adjunct in healing sickle cell leg ulcers and preventing their recurrence.

  10. A Brief Survey Paper on Multi-Legged Robots

    Directory of Open Access Journals (Sweden)

    Mohammad Behmanesh

    2015-03-01

    Full Text Available This paper presents a brief survey on multi-legged robots and their applications in agriculture such as for harvesting. Multi-legged robots have the benefit of more flexibility and adapt to different rough terrain in a better way. They also have very important applications in fulfilling the dangerous tasks such as mine detecting.

  11. Ubx Regulates Differential Enlargement and Diversification of Insect Hind Legs

    Science.gov (United States)

    Mahfooz, Najmus; Turchyn, Nataliya; Mihajlovic, Michelle; Hrycaj, Steven; Popadić, Aleksandar

    2007-01-01

    Differential enlargement of hind (T3) legs represents one of the hallmarks of insect evolution. However, the actual mechanism(s) responsible are yet to be determined. To address this issue, we have now studied the molecular basis of T3 leg enlargement in Oncopeltus fasciatus (milkweed bug) and Acheta domesticus (house cricket). In Oncopeltus, the T3 tibia displays a moderate increase in size, whereas in Acheta, the T3 femur, tibia, and tarsus are all greatly enlarged. Here, we show that the hox gene Ultrabithorax (Ubx) is expressed in the enlarged segments of hind legs. Furthermore, we demonstrate that depletion of Ubx during embryogenesis has a primary effect in T3 legs and causes shortening of leg segments that are enlarged in a wild type. This result shows that Ubx is regulating the differential growth and enlargement of T3 legs in both Oncopeltus and Acheta. The emerging view suggests that Ubx was co-opted for a novel role in regulating leg growth and that the transcriptional modification of its expression may be a universal mechanism for the evolutionary diversification of insect hind legs. PMID:17848997

  12. Restless Legs Syndrome -- Self-Tests and Diagnosis

    Science.gov (United States)

    ... Overview & Facts Causes & Symptoms Self-Tests & Diagnosis Treatment Restless Legs Syndrome - Self-Tests & Diagnosis Self-Tests Do you have ... to any of these questions you may have restless legs syndrome Diagnosis Talk to a board certified sleep medicine ...

  13. Criteria in diagnosing nocturnal leg cramps : a systematic review

    NARCIS (Netherlands)

    Hallegraeff, Joannes; de Greef, Mathieu; Krijnen, Wim; van der Schans, Cees

    2017-01-01

    Background: Up to 33% of the general population over 50 years of age are affected by nocturnal leg cramps. Currently there are no generally accepted clinical characteristics, which identify nocturnal leg cramps. This study aims to identify these clinical characteristics and to differentiate between

  14. X-Ray Exam: Lower Leg (Tibia and Fibula)

    Science.gov (United States)

    ... 2-Year-Old X-Ray Exam: Lower Leg (Tibia and Fibula) KidsHealth > For Parents > X-Ray Exam: Lower Leg (Tibia and Fibula) A A A What's in this ... Child If You Have Questions en español Radiografía: tibia y peroné What It Is An X-ray ...

  15. Beengebrekenonderzoek bij varkens = Research on leg weakness / osteochondrosis in swine

    NARCIS (Netherlands)

    Wal, van der P.G.

    1983-01-01

    Uit onderzoek bleek dat leg weakness, de uiterlijke verschijnselen van beengebreken, niet het resultaat is van osteochondrosis, een verstoring van het verbeningsproces van kraakbeen. De ontwikkeling van de symptomen van leg weakness kunnen onderdrukt worden door natriumbicarbonaat aan het voer toe

  16. Leg length, sitting height and postmenopausal breast cancer risk

    DEFF Research Database (Denmark)

    Mellemkjær, L; Christensen, J; Frederiksen, K

    2012-01-01

    Tallness has consistently been associated with an increased risk of breast cancer. We investigated the association further by decomposing height into leg length and sitting height.......Tallness has consistently been associated with an increased risk of breast cancer. We investigated the association further by decomposing height into leg length and sitting height....

  17. Ubx regulates differential enlargement and diversification of insect hind legs.

    Directory of Open Access Journals (Sweden)

    Najmus Mahfooz

    Full Text Available Differential enlargement of hind (T3 legs represents one of the hallmarks of insect evolution. However, the actual mechanism(s responsible are yet to be determined. To address this issue, we have now studied the molecular basis of T3 leg enlargement in Oncopeltus fasciatus (milkweed bug and Acheta domesticus (house cricket. In Oncopeltus, the T3 tibia displays a moderate increase in size, whereas in Acheta, the T3 femur, tibia, and tarsus are all greatly enlarged. Here, we show that the hox gene Ultrabithorax (Ubx is expressed in the enlarged segments of hind legs. Furthermore, we demonstrate that depletion of Ubx during embryogenesis has a primary effect in T3 legs and causes shortening of leg segments that are enlarged in a wild type. This result shows that Ubx is regulating the differential growth and enlargement of T3 legs in both Oncopeltus and Acheta. The emerging view suggests that Ubx was co-opted for a novel role in regulating leg growth and that the transcriptional modification of its expression may be a universal mechanism for the evolutionary diversification of insect hind legs.

  18. Ontogenetic shifts in functional morphology of dragonfly legs (Odonata: Anisoptera).

    Science.gov (United States)

    Leipelt, Klaus Guido; Suhling, Frank; Gorb, Stanislav N

    2010-12-01

    Anisopteran leg functions change dramatically from the final larval stadium to the adult. Larvae use legs mainly for locomotion, walking, climbing, clinging, or burrowing. Adults use them for foraging and grasping mates, for perching, clinging to the vegetation, and for repelling rivals. In order to estimate the ontogenetic shift in the leg construction from the larva to the adult, this study quantitatively compared lengths of fore, mid, and hind legs and the relationships between three leg segments, femur, tibia, and tarsus, in larval and adult Anisoptera of the families Gomphidae, Aeshnidae, Cordulegastridae, Corduliidae, and Libellulidae, represented by two species each. We found that leg segment length ratio as well as ontogenetic shift in length ratios was different between families, but rather similar within the families. While little ontogenetic shift occurred in Aeshnidae, there were some modifications in Corduliidae and Libellulidae. The severest shift occurred in Gomphidae and Cordulegastridae, both having burrowing larvae. These two families form a cluster, which is in contrast to their taxonomic relationship within the Anisoptera. Cluster analysis implies that the function of larval legs is primarily responsible for grouping, whereas adult behavior or the taxonomic relationships do not explain the grouping. This result supports the previous hypothesis about the convergent functional shift of leg characters in the dragonfly ontogenesis.

  19. Impact of Restless Legs Syndrome on Cardiovascular Autonomic Control.

    Science.gov (United States)

    Bertisch, Suzanne M; Muresan, Cristen; Schoerning, Laura; Winkelman, John W; Taylor, J Andrew

    2016-03-01

    To examine whether patients with restless legs syndrome demonstrate specific alterations in cardiovascular autonomic control. Patients with moderate-severe restless legs syndrome (n = 20, 80% female) and controls (n = 20) matched for age, sex, body mass index, and free of hypertension and cardiovascular disease were enrolled. We assessed cardiovagal baroreflex gain via the modified Oxford technique, sympathetically mediated vascular responses to isometric exercise to fatigue, bradycardiac response to Valsalva maneuver, and respiratory sinus arrhythmia during paced breathing. Standard electrocardiography, beat-by-beat arterial pressure, respiration, and popliteal blood flow velocity were recorded continuously. Resting blood pressure and heart rate were similar between groups. However, baroreflex gain averaged 14.3 ± 1.4 msec/mm Hg in restless legs syndrome and was lower than in controls (22.6 ± 3.5 msec/mm Hg, P = 0.04). Hemodynamic responses to isometric exercise were similar between groups, though participants with restless legs syndrome had lower leg blood flow (P leg vascular resistance (P legs syndrome demonstrate compromised cardiovagal control, specific to the arterial baroreflex, with greater peripheral vascular resistance, potentially due to heightened sympathetic outflow. These autonomic alterations may directly relate to the higher prevalence of cardiovascular disease in restless legs syndrome. © 2016 Associated Professional Sleep Societies, LLC.

  20. The recalcitrant venous leg ulcer - A never ending story?

    NARCIS (Netherlands)

    S.W.I. Reeder (Suzan); M.B. Maessen-Visch (Birgitte); S.I. Langendoen; K.P. de Roos; H.A.M. Neumann (Martino)

    2013-01-01

    textabstractIntroduction: In general, four particular causes of recalcitrant venous leg ulcers may be distinguished. These are foot pump insufficiency, chronic venous compartment syndrome and non-re-canalized popliteal vein thrombosis. The fourth cause of recalcitrant venous leg ulcers is lipodermat

  1. Restless legs syndrome in opioid dependent patients

    Directory of Open Access Journals (Sweden)

    Abhishek Ghosh

    2014-01-01

    Full Text Available Although frequently underdiagnosed, several epidemiological studies have estimated the prevalence of restless legs syndrome (RLS in western countries at 5-15% of the general population. The diagnosis is usually made on a clinical basis, according to the criteria established by the international RLS study group. There are case reports of transient RLS in opiate withdrawal. We describe three opiate (dextropropoxyphene (DPP dependent young male patients; two of them had DPP intoxication/withdrawal seizure developing RLS during opiate withdrawal. However, their RLS persisted even after the remission of other withdrawal symptoms. Thyroid function test, hemogram, serum ferritin were normal in all of them. The cases responded well to a treatment with ropinirole. Hence, there might be a causal association, which required further well-designed studies to substantiate. The sleep disturbances and use of benzodiazepines can be minimized by increasing clinician′s sensitivity to diagnose RLS.

  2. Series Elastic Actuators for legged robots

    Science.gov (United States)

    Pratt, Jerry E.; Krupp, Benjamin T.

    2004-09-01

    Series Elastic Actuators provide many benefits in force control of robots in unconstrained environments. These benefits include high force fidelity, extremely low impedance, low friction, and good force control bandwidth. Series Elastic Actuators employ a novel mechanical design architecture which goes against the common machine design principal of "stiffer is better." A compliant element is placed between the gear train and driven load to intentionally reduce the stiffness of the actuator. A position sensor measures the deflection, and the force output is accurately calculated using Hooke"s Law (F=Kx). A control loop then servos the actuator to the desired output force. The resulting actuator has inherent shock tolerance, high force fidelity and extremely low impedance. These characteristics are desirable in many applications including legged robots, exoskeletons for human performance amplification, robotic arms, haptic interfaces, and adaptive suspensions. We describe several variations of Series Elastic Actuators that have been developed using both electric and hydraulic components.

  3. Acute Compartment Syndrome of the Leg.

    Science.gov (United States)

    Konda, Sanjit R; Kester, Benjamin S; Fisher, Nina; Behery, Omar A; Crespo, Alexander M; Egol, Kenneth A

    2017-08-01

    Acute compartment syndrome (ACS) is well known among orthopaedic surgeons. The timely diagnosis and management of ACS is crucial to avoiding its sequelae, including renal failure, ischemic contractures, and limb loss. Despite its relative importance, ACS poses a challenge to many residents and clinicians as diagnosis relies largely on clinical judgment. Timely diagnosis and thorough compartment release are essential to optimizing outcomes in ACS. This video highlights a clinical case in which compartment syndrome of the leg was considered, diagnosed, and surgically managed. This video will present the indications for compartment release and a video-guided demonstration of compartment checks using an arterial line transducer, a 4-compartment fasciotomy with 2 incisions, and temporizing vessel loop closure. Compartment syndrome can be a devastating complication of common fractures. It is essential that orthopaedic practitioners understand the immediacy of intervention. We have a responsibility to provide timely, accurate diagnosis along with expedient surgical management.

  4. Integrated design of legged mechatronic system

    Institute of Scientific and Technical Information of China (English)

    ChinYin CHEN; IMing CHEN; ChiCheng CHENG

    2009-01-01

    This paper presents a system based on the integrated design and experiment for a one degree-of-freedom (DOF) legged mechatronic system (LMTS). A six-bar linkage mechanism, which is derived from a four-bar linkage with a symmetrical coupler point and pantograph into one, is designed, and common controllers are used to control the velocity and position loops.For system-based dynamic optimization, the design for control (DFC) approach is used to integrate the structure and control for improving dynamic performance with reduced control torque.Finally, for a rapid 3D graphical based implementation of the system, high-level computer-aided rapid system integration (CARSI) technology is used to integrate the structure design, controller design, and system implemen-tation into the design and analytical software environment based on Pro/engineer, XML syntax, Simmechanics, and Simulink. Thus, the development time for the LMTS is reduced.

  5. May 2015 critical care case of the month: an infected leg

    Directory of Open Access Journals (Sweden)

    Till SL

    2015-05-01

    Full Text Available No abstract available. Article truncated at 150 words. History of Present Illness: A 46-year-old transferred due to concern for necrotizing fasciitis. One the day prior to transfer purple discoloration was not noted in the lower portion of the left leg. On the day of transfer the leg became more purple, painful, and swollen. She presented to a pain clinic that advised her to go to an emergency room. The emergency room performed arterial Doppler ultrasound, which was normal and transferred her due to concern of necrotizing fasciitis. Past Medical History, Social History and Family History: She has a past medical history of fibromyalgia. She had an extensive surgical history including an appendectomy, bladder implant, cholecystectomy, dilatation and curettage, esophageal repair, left femoral artery repair due to a motor vehicle accident, partial hysterectomy, left knee surgery, and several left leg operations with grafting. Family history was non-contributory. The patient was single with two children, and smoked 1-2 packs of ...

  6. Computer-assisted 3D kinematic analysis of all leg joints in walking insects.

    Directory of Open Access Journals (Sweden)

    John A Bender

    Full Text Available High-speed video can provide fine-scaled analysis of animal behavior. However, extracting behavioral data from video sequences is a time-consuming, tedious, subjective task. These issues are exacerbated where accurate behavioral descriptions require analysis of multiple points in three dimensions. We describe a new computer program written to assist a user in simultaneously extracting three-dimensional kinematics of multiple points on each of an insect's six legs. Digital video of a walking cockroach was collected in grayscale at 500 fps from two synchronized, calibrated cameras. We improved the legs' visibility by painting white dots on the joints, similar to techniques used for digitizing human motion. Compared to manual digitization of 26 points on the legs over a single, 8-second bout of walking (or 106,496 individual 3D points, our software achieved approximately 90% of the accuracy with 10% of the labor. Our experimental design reduced the complexity of the tracking problem by tethering the insect and allowing it to walk in place on a lightly oiled glass surface, but in principle, the algorithms implemented are extensible to free walking. Our software is free and open-source, written in the free language Python and including a graphical user interface for configuration and control. We encourage collaborative enhancements to make this tool both better and widely utilized.

  7. Leg length discrepancy in scoliotic patients.

    Science.gov (United States)

    D'Amico, Moreno; Roncoletta, Piero; Di Felice, Francesca; Porto, Daniele; Bellomo, Rosagrazia; Saggini, Raoul

    2012-01-01

    The aetiological aspects as well as postural attitude implications represent an open question in scoliosis evaluation and treatment. Leg length discrepancy (LLD) is often recognised in scoliotic patients, but surprisingly still controversial is the use of underfoot wedge corrections in order to compensate pelvis tilt. In fact, literature reports conflicting results on the efficacy of LLD equalization also given the argued uncertainty of LLD clinical assessment and limitations related to X-ray measurements. Moreover concern is about anatomic and functional LLD and associated estimation of the pelvic torsion. In such a topic, a significant helpful tool has been demonstrated to be 3D kinematic optoelectronic measurements and other useful data obtained from force platforms and/or baropodographic systems. 135 (94.4%) out of 143 Scoliotic patients sample (av. age 16.4±10.2 Y range 4-66 Y), have been found to improve posture when LLD was corrected. The 143 patients showed a mean lower limb discrepancy of μ=10.2±5.2mm associated to a mean main scoliotic curve μ=16.4°±9.4° Cobb (frontal plane), mean Spinal offset μ=7.5±5.5mm and mean Global offset μ=10.1±7.1mm. The applied paired t-test comparison (indifferent vs. corrected orthostasis) showed significant (p < 0.05) postural improvements could be obtained in the whole or in a part of the considered postural parameters, after the application of suitable under-foot wedge. The present investigation confirm results of a previous study demonstrating the efficacy of under-foot wedge use in leg asymmetry correction, posture re-balancing and spine deformities reduction, pointing out the significant contribution of the 3D opto-electronic measurement approach in the critical process of assessing the correct under-foot wedge size, therapy planning and monitoring.

  8. Restless legs syndrome in patients on hemodialysis

    Directory of Open Access Journals (Sweden)

    Saleh Mohammad Yaser Salman

    2011-01-01

    Full Text Available Restless legs syndrome (RLS is common among dialysis patients, with a reported prevalence of 6-60%. The prevalence of RLS in Syrian patients on hemodialysis (HD is not known. The purpose of this study is to determine the prevalence of RLS in patients on regular HD, and to find the possible correlation between the presence of RLS and demographic, clinical, and biochemical factors. One hundred and twenty-three patients (male/female = 70/53, mean age = 41.95 ± 15.11 years on HD therapy at the Aleppo University Hospital were enrolled into the study. RLS was diagnosed based on criteria established by the International Restless Legs Syn-drome Study Group (IRLSSG. Data procured were compared between patients with and without RLS. Applying the IRLSSG criteria for the diagnosis, RLS was seen in 20.3% of the study pa-tients. No significant difference in age, gender, and intake of nicotine and caffeine was found between patients with and without the RLS. Similarly, there was no difference between the two groups in the duration of end-stage renal disease (ESRD, the period of dialysis dependence, dialysis adequacy, urea and creatinine levels, and the presence of anemia. The co-morbidities and the use of drugs also did not differ in the two groups. Our study suggests that the high prevalence of RLS among patients on HD requires careful attention and correct diagnosis can lead to better therapy and better quality of life. The pathogenesis of RLS is not clear and further studies are required to identify any possible cause as well as to discover the impact of this syndrome on sleep, quality of life, and possibly other complications such as cardiovasculare disease.

  9. Restless legs syndrome in patients on hemodialysis.

    Science.gov (United States)

    Salman, Saleh Mohammad Yaser

    2011-03-01

    Restless legs syndrome (RLS) is common among dialysis patients, with a reported prevalence of 6-60%. The prevalence of RLS in Syrian patients on hemodialysis (HD) is not known. The purpose of this study is to determine the prevalence of RLS in patients on regular HD, and to find the possible correlation between the presence of RLS and demographic, clinical, and biochemical factors. One hundred and twenty-three patients (male/female = 70/53, mean age = 41.95 ± 15.11 years) on HD therapy at the Aleppo University Hospital were enrolled into the study. RLS was diagnosed based on criteria established by the International Restless Legs Syn-drome Study Group (IRLSSG). Data procured were compared between patients with and without RLS. Applying the IRLSSG criteria for the diagnosis, RLS was seen in 20.3% of the study pa-tients. No significant difference in age, gender, and intake of nicotine and caffeine was found between patients with and without the RLS. Similarly, there was no difference between the two groups in the duration of end-stage renal disease (ESRD), the period of dialysis dependence, dialysis adequacy, urea and creatinine levels, and the presence of anemia. The co-morbidities and the use of drugs also did not differ in the two groups. Our study suggests that the high prevalence of RLS among patients on HD requires careful attention and correct diagnosis can lead to better therapy and better quality of life. The pathogenesis of RLS is not clear and further studies are required to identify any possible cause as well as to discover the impact of this syndrome on sleep, quality of life, and possibly other complications such as cardiovasculare disease.

  10. Short-interval leg movements during sleep entail greater cardiac activation than periodic leg movements during sleep in restless legs syndrome patients.

    Science.gov (United States)

    Ferri, Raffaele; Rundo, Francesco; Silvani, Alessandro; Zucconi, Marco; Aricò, Debora; Bruni, Oliviero; Lanuzza, Bartolo; Ferini-Strambi, Luigi; Manconi, Mauro

    2017-10-01

    Periodic leg movements during sleep (PLMS) are sequences of ≥4 motor events with intermovement intervals (IMI) of 10-90 s. PLMS are a supportive diagnostic criterion for restless legs syndrome (RLS) and entail cardiac activation, particularly when associated with arousal. RLS patients also over-express short-interval leg movements during sleep (SILMS), which have IMI leg movements. We found that the duration of the R-R interval decrease with SILMS doublets was significantly longer than that with PLMS, whereas the maximal decrease in R-R interval was similar. Scoring SILMS in RLS patients may therefore be relevant from a cardiac autonomic perspective. © 2017 European Sleep Research Society.

  11. A Terradynamics of Legged Locomotion on Granular Media

    CERN Document Server

    Li, Chen; Goldman, Daniel I; 10.1126/science.1229163

    2013-01-01

    The theories of aero- and hydrodynamics predict animal movement and device design in air and water through the computation of lift, drag, and thrust forces. Although models of terrestrial legged locomotion have focused on interactions with solid ground, many animals move on substrates that flow in response to intrusion. However, locomotor-ground interaction models on such flowable ground are often unavailable. We developed a force model for arbitrarily-shaped legs and bodies moving freely in granular media, and used this "terradynamics" to predict a small legged robot's locomotion on granular media using various leg shapes and stride frequencies. Our study reveals a complex but generic dependence of stresses in granular media on intruder depth, orientation, and movement direction and gives insight into the effects of leg morphology and kinematics on movement.

  12. Adaptive leg coordination with a biologically inspired neurocontroller

    Science.gov (United States)

    Braught, Grant; Thomopoulos, Stelios C.

    1996-10-01

    Natural selection is responsible for the creation of robust and adaptive control systems. Nature's control systems are created only from primitive building blocks. Using insect neurophysiology as a guide, a neural architecture for leg coordination in a hexapod robot has been developed. Reflex chains and sensory feedback mechanisms from various insects and crustacea form the basis of a pattern generator for intra-leg coordination. The pattern generator contains neural oscillators which learn from sensory feedback to produce stepping patterns. Using sensory feedback as the source of learning information allows the pattern generator to adapt to changes in the leg dynamics due to internal or external causes. A coupling between six of the single leg pattern generators is used to produce the inter-leg coordination necessary to establish stable gaits.

  13. Why do arms extract less oxygen than legs during exercise?

    DEFF Research Database (Denmark)

    Calbet, J A L; Holmberg, H-C; Rosdahl, H;

    2005-01-01

    To determine whether conditions for O2 utilization and O2 off-loading from the hemoglobin are different in exercising arms and legs, six cross-country skiers participated in this study. Femoral and subclavian vein blood flow and gases were determined during skiing on a treadmill at approximately 76......% maximal O2 uptake (V(O2)max) and at V(O2)max with different techniques: diagonal stride (combined arm and leg exercise), double poling (predominantly arm exercise), and leg skiing (predominantly leg exercise). The percentage of O2 extraction was always higher for the legs than for the arms. At maximal...... exercise (diagonal stride), the corresponding mean values were 93 and 85% (n = 3; P

  14. Detection of Periodic Leg Movements by Machine Learning Methods Using Polysomnographic Parameters Other Than Leg Electromyography

    Directory of Open Access Journals (Sweden)

    İlhan Umut

    2016-01-01

    Full Text Available The number of channels used for polysomnographic recording frequently causes difficulties for patients because of the many cables connected. Also, it increases the risk of having troubles during recording process and increases the storage volume. In this study, it is intended to detect periodic leg movement (PLM in sleep with the use of the channels except leg electromyography (EMG by analysing polysomnography (PSG data with digital signal processing (DSP and machine learning methods. PSG records of 153 patients of different ages and genders with PLM disorder diagnosis were examined retrospectively. A novel software was developed for the analysis of PSG records. The software utilizes the machine learning algorithms, statistical methods, and DSP methods. In order to classify PLM, popular machine learning methods (multilayer perceptron, K-nearest neighbour, and random forests and logistic regression were used. Comparison of classified results showed that while K-nearest neighbour classification algorithm had higher average classification rate (91.87% and lower average classification error value (RMSE = 0.2850, multilayer perceptron algorithm had the lowest average classification rate (83.29% and the highest average classification error value (RMSE = 0.3705. Results showed that PLM can be classified with high accuracy (91.87% without leg EMG record being present.

  15. Effects of gabapentin enacarbil on restless legs syndrome and leg pain in dementia with Lewy bodies.

    Science.gov (United States)

    Fujishiro, Hiroshige

    2014-06-01

    Restless legs syndrome (RLS) is a common neurological disorder. Dementia with Lewy bodies (DLB) is the second most common form of neurodegenerative dementia after Alzheimer's disease. Both RLS and DLB can be effectively treated by dopaminergic medications, suggesting the role of dopamine dysfunction in the pathogenesis of both diseases. Here, I report on a Japanese woman with probable DLB and RLS who was treated with gabapentin enacarbil, a non-dopaminergic agent. Because a dopamine agonist, a first-line therapy for moderate to severe RLS, caused the occurrence of metamorphopsia, an alternative treatment of gabapentin enacarbil was used; this treatment improved the patient's RLS without worsening her psychiatric symptoms. An alternative treatment is desirable for DLB patients with RLS because they often experience intolerable side-effects with a dopamine agonist, especially visual hallucinations. Administering gabapentin enacarbil also improved the continuous leg pain that occurred in conjunction with the development of RLS. Although the neurobiological mechanism in the development of pain remains unclear, a range of non-dopaminergic structures likely mediated pain processing in DLB in the present case based on neuropharmacological results. This is the first report reporting the effects of gabapentin enacarbil for RLS and leg pain in a DLB patient with psychiatric symptoms.

  16. Validation of a leg movements count and periodic leg movements analysis in a custom polysomnography system.

    Science.gov (United States)

    Stefani, Ambra; Heidbreder, Anna; Hackner, Heinz; Högl, Birgit

    2017-02-23

    Periodic leg movements (PLM) during sleep (PLMS) are considered strongly related to restless legs syndrome (RLS), and are associated with polymorphisms in RLS risk genes. Various software for automatic analysis of PLMS are available, but only few of them have been validated. Aim of this study was to validate a leg movements count and analysis integrated in a commercially available polysomnography (PSG) system against manual scoring. Twenty RLS patients with a PLMS index > 20/h and 20 controls with a PLMS index PLM was performed according to the standard American Academy of Sleep Medicine (AASM) criteria. LM and PLM indices during sleep and wakefulness, the rate of PLMS associated with respiratory events, intermovement interval and periodicity indices were manually and automatically scored. The correlation between manual and computerized scoring was high for all investigated parameters (Spearman correlation coefficients 0.751-0.996, p PLM analysis against the gold standard manual scoring according to AASM criteria. The data demonstrate that the software used in this study has an outstanding performance for computerized LM and PLM scoring, and LM and PLM indices generated with this software can be reliably integrated in the routine PSG report. This automatic analysis is also an excellent tool for research purposes.

  17. Investigation into the correlation between sensation and leg movement in restless legs syndrome.

    Science.gov (United States)

    Birinyi, Paul V; Allen, Richard P; Lesage, Susan; Dean, Terry; Earley, Christopher J

    2005-09-01

    We evaluated rest effects on restless legs syndrome (RLS) sensory and motor symptoms. During two 60-minute Suggested Immobilization Tests (SIT) subject's signals of RLS leg sensations and periodic leg movements while awake (PLMW) were recorded. Sensations, PLMW, sensations preceding or after PLMW, sensations occurring without following PLMW, and PLMW occurring without preceding sensation were determined. The RLS patients were divided into equal-sized high and low PLMW groups for further analysis. Data from 46 subjects (28 RLS and 18 controls) revealed sensations increased linearly with rest in RLS patients and controls. Movement rate increased linearly with rest for controls but increased rapidly for the first 45 minutes for all RLS patients. PLMW/hour increased with further rest for low but not high PLMW patients. Sensations followed by PLMW and PLMW without preceding sensations followed similar patterns. Sensations without subsequent PLMW increased dramatically in the last 15 minutes of the SITs. Whereas both sensory and motor signs of RLS increase with rest, there is minimal increase for controls. Patients with higher but not lower PLMW rates reached a ceiling for PLMW after 35 to 40 minutes. The temporal dissociation between sensory and motor events supports viewing these motor and sensory events as separate but loosely linked manifestations of RLS. (c) 2005 Movement Disorder Society.

  18. Leg stiffness and stride frequency in human running.

    Science.gov (United States)

    Farley, C T; González, O

    1996-02-01

    When humans and other mammals run, the body's complex system of muscle, tendon and ligament springs behaves like a single linear spring ('leg spring'). A simple spring-mass model, consisting of a single linear leg spring and a mass equivalent to the animal's mass, has been shown to describe the mechanics of running remarkably well. Force platform measurements from running animals, including humans, have shown that the stiffness of the leg spring remains nearly the same at all speeds and that the spring-mass system is adjusted for higher speeds by increasing the angle swept by the leg spring. The goal of the present study is to determine the relative importance of changes to the leg spring stiffness and the angle swept by the leg spring when humans alter their stride frequency at a given running speed. Human subjects ran on treadmill-mounted force platform at 2.5ms-1 while using a range of stride frequencies from 26% below to 36% above the preferred stride frequency. Force platform measurements revealed that the stiffness of the leg spring increased by 2.3-fold from 7.0 to 16.3 kNm-1 between the lowest and highest stride frequencies. The angle swept by the leg spring decreased at higher stride frequencies, partially offsetting the effect of the increased leg spring stiffness on the mechanical behavior of the spring-mass system. We conclude that the most important adjustment to the body's spring system to accommodate higher stride frequencies is that leg spring becomes stiffer.

  19. Kentucky's Urban Extension Focus

    Science.gov (United States)

    Young, Jeffery; Vavrina, Charles

    2014-01-01

    Defining the success of Urban Extension units is sometimes challenging. For those Extension agents, specialists, administrators, and others who have worked to bring solid, research-based programming to urban communities, it is no surprise that working in these communities brings its own unique and sometimes difficult challenges. Kentucky's Urban…

  20. 78 FR 68909 - Agency Information Collection (Knee and Lower Leg Conditions Disability Benefits Questionnaire...

    Science.gov (United States)

    2013-11-15

    ... AFFAIRS Agency Information Collection (Knee and Lower Leg Conditions Disability Benefits Questionnaire... Leg Conditions Disability Benefits Questionnaire)'' in any correspondence. FOR FURTHER INFORMATION... Control No. 2900-NEW (Knee and Lower Leg Conditions Disability Benefits Questionnaire)''....