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Sample records for stretching groups performed

  1. Static versus dynamic stretching: Chronic and acute effects on Agility performance in male athletes

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    Iman Taleb-Beydokhti

    2015-04-01

    Full Text Available The purpose of this study was to examine the acute and chronic effects of static & dynamic stretching protocols on agility performance in amateur handball players. Twelve male amateur handball players (age: 19.66 ± 4.02 years old, weight: 67.12 ± 8.73 kg, height: 178.29 ± 7.81 cm participated in this study. The athletes were randomly allocated into two groups: static stretching or dynamic stretching. All of them underwent an initial evaluation and were submitted to the first intervention. They were evaluated once again and at the end of 12 training sessions. The results analyzed using ANOVA showed that there was a significant decrease in agility time after dynamic stretching against no stretching in the acute phase; but, there were no significant differences between dynamic stretching and no stretching in the chronic phase. In addition, there was no a significant difference between no stretching and static stretching in the acute phase; while, There was a significant decrease in agility time after no stretching against static stretching in the chronic phase. It was concluded that acute dynamic stretching as part of a warm-up may decrease agility time performance, whereas static stretching seems to increase agility time performance. Consequently, the acute and chronic static stretching should not be performed prior to an explosive athletic performance. Keywords: Handball, Agility, Dynamic stretching, Static stretching

  2. EFFECT OF DIFFERENT STRETCHING PROTOCOLS ON VERTICAL JUMP PERFORMANCE

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    Emre Serin

    2018-04-01

    Full Text Available This study aimed to examine the effect of different stretching exercises on vertical jump performance. A total of 14 national male athletes sporting in the elite level took part in the study. The age average of the participants was 20.25±1.03 year, the average height was 1.80±.08 m, the average body weight was 77.14±18.91 kg, average of sporting age was 9.87±3.31 year and the average number of participation in international games was 10.0±3.31. As stretching protocol: Method 1 (5 minutes of jogging and 2 minutes of active rest followed by Method 2 (static stretching for 4 different muscle groups 3 repetitions for 15 seconds of static stretching, rest for 10 seconds between groups and then consecutively, Method 3 (Dynamic stretching exercises with 3 repetitions for 15 seconds and 10 seconds rest between different muscle groups were applied in the study. The vertical jump performance before and after different stretching exercises of the participants was determined by means of the vertical jump test using the smart speed lite system. Before and after the training of all athletes, HR was recorded with a heart rate monitor (RS 800, Polar Vantage NV, Polar Electro Oy, Finland with 5 seconds intervals. Before the study, the chest band of the heartbeat monitor was placed on the chest of the athlete and the HR was recorded from the monitor. SPSS 15.0 statistical package program was used for evaluation and calculation of the data. In this study in addition to descriptive statistics (mean and standard deviation paired samples t-test was used to determine the difference between the vertical jump performance of the participants before and after different stretching exercises. As a result, this study showed that; applying the dynamic and static stretching exercises consecutively affected the vertical jump performance 4.5 cm positively (p<.05. It is suggested that different dynamic and static stretching exercises should be included in the vertical jump.

  3. Stretching

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    ... after a workout. Stretching still can be a beneficial activity after you have sufficiently warmed up. The ... light aerobic activity and stretching. If you're running at a quick pace, you can slow down ...

  4. The acute effect of static and dynamic stretching during warm-ups on anaerobic performance in trained women

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    rouhollah haghshenas

    2014-09-01

    Full Text Available The purpose of this study was to investigate effects of static stretching, dynamic stretching and no stretching methods on power and speed in volleyball players. Therefore, Twenty-four volleyball players (height: 173.29 ± 7.81 m; mass: 62.12 ± 8.73 kg; age: 22.66 ± 4.02 years; experience: 3.27 ± 6.37 were tested for speed performance using the 20 meter sprint test and also for power using vertical jump test after static stretching, dynamic stretching and no stretching. The results analyzed using ANOVA showed that There was a significant increase in height jump after dynamic stretching against static stretching. But, there were no significant differences between no stretching and static stretching groups. In addition, there was a significant decrease in time 20 meter sprint after dynamic stretching against static stretching and no stretching groups. The results of this study suggest that it may be desirable for volleyball players to perform dynamic exercises before the performance of activities that require a high power output.

  5. Upper Limb Static-Stretching Protocol Decreases Maximal Concentric Jump Performance

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    Paulo H. Marchetti

    2014-12-01

    Full Text Available The purpose of the present study was to evaluate the acute effects of an upper limb static-stretching (SS protocol on the maximal concentric jump performance. We recruited 25 young healthy, male, resistance trained individuals (stretched group, n = 15 and control group, n = 10 in this study. The randomized between group experimental protocol consisted of a three trials of maximal concentric jump task, before and after a SS of the upper limb. Vertical ground reaction forces (vGRF and surface electromyography (sEMG of both gastrocnemius lateralis (GL and vastus lateralis (VL were acquired. An extensive SS was employed consisting of ten stretches of 30 seconds, with 15 seconds of rest, and 70-90% of the point of discomfort (POD. ANOVA (2x2 (group x condition was used for shoulder joint range of motion (ROM, vGRF and sEMG. A significant interaction for passive ROM of the shoulder joint revealed significant increases between pre- and post-SS protocol (p < 0.001. A significant interaction demonstrated decreased peak force and an increased peak propulsion duration between pre- and post-stretching only for stretch group (p = 0.021, and p = 0.024, respectively. There was a significant main effect between groups (stretch and control for peak force for control group (p = 0.045. Regarding sEMG variables, there were no significant differences between groups (control versus stretched or condition (pre-stretching versus post-stretching for the peak amplitude of RMS and IEMG for both muscles (VL and GL. In conclusion, an acute extensive SS can increase the shoulder ROM, and negatively affect both the propulsion duration and peak force of the maximal concentric jump, without providing significant changes in muscle activation.

  6. Effect of spinal manipulative therapy with stretching compared with stretching alone on full-swing performance of golf players: a randomized pilot trial☆

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    Costa, Soraya M.V.; Chibana, Yumi E.T.; Giavarotti, Leandro; Compagnoni, Débora S.; Shiono, Adriana H.; Satie, Janice; Bracher, Eduardo S.B.

    2009-01-01

    Abstract Objective There has been a steady growth of chiropractic treatment using spinal manipulative therapy (SMT) that aims to increase the performance of athletes in various sports. This study evaluates the effect of SMT by chiropractors on the performance of golf players. Methods Golfers of 2 golf clubs in São Paulo, Brazil, participated in this study. They were randomized to 1 of 2 groups: Group I received a stretch program, and group II received a stretch program in addition to SMT. Participants in both groups performed the same standardized stretching program. Spinal manipulative therapy to dysfunctional spinal segments was performed on group II only. All golfers performed 3 full-swing maneuvers. Ball range was considered as the average distance for the 3 shots. Treatment was performed after the initial measurement, and the same maneuvers were performed afterward. Each participant repeated these procedures for a 4-week period. Student t test, Mann-Whitney nonparametric test, and 1-way analysis of variance for repeated measures with significance level of 5% were used to analyze the study. Results Forty-three golfers completed the protocol. Twenty participants were allocated to group I and 23 to group II. Average age, handicap, and initial swing were comparable. No improvement of full-swing performance was observed during the 4 sessions on group I (stretch only). An improvement was observed at the fourth session of group II (P = .005); when comparing the posttreatment, group II had statistical significance at all phases (P = .003). Conclusions Chiropractic SMT in association with muscle stretching may be associated with an improvement of full-swing performance when compared with muscle stretching alone. PMID:19948307

  7. Acute Effect of Static Stretching on Lower Limb Movement Performance by Using STABL Virtual Reality System.

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    Ameer, Mariam A; Muaidi, Qassim I

    2017-07-17

    The effect of acute static stretch (ASS) on the lower limb RT has been recently questioned to decrease the risk of falling and injuries in situations requiring a rapid reaction, as in the cases of balance disturbance. The main purpose of this study was to detect the effect of ASS on the lower limb RT by using virtual reality device. Two Group Control Group design. Research laboratory. The control and experimental groups were formed randomly from sixty female university students. Each participant in the experimental group was tested before and after ASS for the quadriceps, hamstrings and planter flexor muscles, and compared with the control group with warming-up exercise only. The stretching program involved warming-up in the form of circular running inside the lab for 5 minutes followed by stretching of each muscle group thrice, to the limit of discomfort of 45 s, with resting period of 15s between stretches. The measurements included the RT of the dominant lower extremity by using the dynamic stability program, STABL Virtual Reality System (Model No. DIZ 2709, Motek Medical and Force Link Merged Co., Amsterdam). There was statistically significant reduction (F = 162, P= .00) in post-test RT between the two groups, and significant decrease in RT after stretching, in the experimental group (7.5%) (P= .00). ASS of the lower limb muscles tends to decrease the lower limb RT and improve movement performance.

  8. The effects of stretching on the flexibility, muscle performance and functionality of institutionalized older women

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    D. Gallon

    2011-03-01

    Full Text Available Stretching has been widely used to increase the range of motion. We assessed the effects of a stretching program on muscle-tendon length, flexibility, torque, and activities of daily living of institutionalized older women. Inclusion/exclusion criteria were according to Mini-Mental State Examination (MMSE (>13, Barthel Index (>13 and Lysholm Scoring Scale (>84. Seventeen 67 ± 9 year-old elderly women from a nursing home were divided into 2 groups at random: the control group (CG, N = 9 participated in enjoyable cultural activities; the stretching group (SG, N = 8 performed active stretching of hamstrings, 4 bouts of 1 min each. Both groups were supervised three times per week over a period of 8 weeks. Peak torque was assessed by an isokinetic method. Both groups were evaluated by a photogrammetric method to assess muscle-tendon length of uni- and biarticular hip flexors and hamstring flexibility. All measurements were analyzed before and after 8 weeks by two-way ANOVA with the level of significance set at 5%. Hamstring flexibility increased by 30% in the SG group compared to pre-training (76.5 ± 13.0° vs 59.5 ± 9.0°, P = 0.0002 and by 9.2% compared to the CG group (76.5 ± 13.0° vs 64.0 ± 12.0°, P = 0.0018. Muscle-tendon lengths of hip biarticular flexor muscles (124 ± 6.8° vs 118.3 ± 7.6°, 5.0 ± 7.0%, P = 0.031 and eccentric knee extensor peak torque were decreased in the CG group compared to pre-test values (-49.4 ± 16.8 vs -60.5 ± 18.9 Nm, -15.7 ± 20%, P = 0.048. The stretching program was sufficient to increase hamstring flexibility and a lack of stretching can cause reduction of muscle performance.

  9. Mechanical stretching effect on the actuator performance of cellulose electroactive paper

    International Nuclear Information System (INIS)

    Kim, Jung-Hwan; Yun, Ki-Ju; Kim, Joo-Hyung; Kim, Jaehwan

    2009-01-01

    The mechanical stretching effect on the actuating performance of electroactive cellulose paper (EAPap) was studied. A lattice elongation of cellulose fibrils due to in-plane tensile stress along the stretching direction was observed by the x-ray diffraction method. The shrinkage of the fibril diameter as a function of stretching ratio was confirmed by surface and cross-sectional images. While the actuator performance in terms of bending displacement decreased as the stretching ratio increased, the resonance frequency linearly increased as the stretching ratio increased, which was compared with the theoretical frequency data found from a cantilever beam model. The actuator efficiency was evaluated from the electrical input power consumption and the mechanical output power of an EAPap actuator. It was revealed that the stretching process increased the electro-mechanical efficiency of the EAPap actuator. The mechanism of the influence of the stretching effect on the performance of an EAPap actuator is discussed

  10. ACUTE EFFECTS OF THREE DIFFERENT STRETCHING PROTOCOLS ON THE WINGATE TEST PERFORMANCE

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    Bruno L. Franco

    2012-03-01

    Full Text Available The purpose of this study was to examine the acute effects of different stretching exercises on the performance of the traditional Wingate test (WT. Fifteen male participants performed five WT; one for familiarization (FT, and the remaining four after no stretching (NS, static stretching (SS, dynamic stretching (DS, and proprioceptive neuromuscular facilitation (PNF. Stretches were targeted for the hamstrings, quadriceps, and calf muscles. Peak power (PP, mean power (MP, and the time to reach PP (TP were calculated. The MP was significantly lower when comparing the DS (7.7 ± 0.9 W/kg to the PNF (7.3 ± 0.9 W/kg condition (p < 0.05. For PP, significant differences were observed between more comparisons, with PNF stretching providing the lowest result. A consistent increase of TP was observed after all stretching exercises when compared to NS. The results suggest the type of stretching, or no stretching, should be considered by those who seek higher performance and practice sports that use maximal anaerobic power.

  11. Acute effect of different stretching methods on flexibility and jumping performance in competitive artistic gymnasts.

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    Dallas, G; Smirniotou, A; Tsiganos, G; Tsopani, D; Di Cagno, A; Tsolakis, Ch

    2014-12-01

    The purpose of this study was to investigate the acute effects of 3 different warm up methods of stretching (static, proprioceptive neuromuscular facilitation, and stretching exercises on a Vibration platform) on flexibility and legs power-jumping performance in competitive artistic gymnasts. Eighteen competitive artistic gymnasts were recruited to participate in this study. Subjects were exposed to each of 3 experimental stretching conditions: static stretching (SS), proprioceptive neuromuscular facilitation stretching (PNF), and stretching exercises on a Vibration platform (S+V). Flexibility assessed with sit and reach test (S & R) and jumping performance with squat jump (SJ) and counter movement jump (CMJ) and were measured before, immediately after and 15 min after the interventions. Significant differences were observed for flexibility after all stretching conditions for S+V (+1.1%), SS (+5.7%) and PNF (+6.8%) (P=0.000), which remained higher 15 min after interventions (S+V (1.1%), SS (5.3%) and PNF (5.5%), respectively (P=0.000). PNF stretching increased flexibility in competitive gymnasts, while S+V maintained jumping performance when both methods were used as part of a warm-up procedure.

  12. Sequence-length variation of mtDNA HVS-I C-stretch in Chinese ethnic groups.

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    Chen, Feng; Dang, Yong-hui; Yan, Chun-xia; Liu, Yan-ling; Deng, Ya-jun; Fulton, David J R; Chen, Teng

    2009-10-01

    The purpose of this study was to investigate mitochondrial DNA (mtDNA) hypervariable segment-I (HVS-I) C-stretch variations and explore the significance of these variations in forensic and population genetics studies. The C-stretch sequence variation was studied in 919 unrelated individuals from 8 Chinese ethnic groups using both direct and clone sequencing approaches. Thirty eight C-stretch haplotypes were identified, and some novel and population specific haplotypes were also detected. The C-stretch genetic diversity (GD) values were relatively high, and probability (P) values were low. Additionally, C-stretch length heteroplasmy was observed in approximately 9% of individuals studied. There was a significant correlation (r=-0.961, Ppopulations. The results from the Fst and dA genetic distance matrix, neighbor-joining tree, and principal component map also suggest that C-stretch could be used as a reliable genetic marker in population genetics.

  13. Barriers to performing stretching exercises among Korean-Chinese female migrant workers in Korea.

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    Lee, Hyeonkyeong; Wilbur, JoEllen; Chae, Duckhee; Lee, Kyongeun; Lee, Meenhye

    2015-01-01

    The purpose of this study was to investigate the barriers to performing stretching exercise experienced by Korean-Chinese female migrant workers during a community-based 12-week stretching exercise intervention trial. Qualitative secondary data analysis was conducted using telephone counseling interview transcripts from 27 middle-aged, Korean-Chinese migrant women workers. A semistructured interview question asking barriers to performing stretching exercise was given to women who did not adhere to recommended stretching exercise. During the 12-week home-based stretching exercise intervention trial, six telephone calls were made to participants biweekly to elicit barriers to performing stretching exercise. Directed content analysis approach was utilized using three barrier categories: intrapersonal, interpersonal, and work-related environmental factors based on the ecological model. Participants experienced an average of 2.5 barriers during the study period. Intrapersonal barriers included lack of time and lack of motivation, and interpersonal barriers included no family to provide support and also a feeling resistance from coworkers. Work-related environmental barriers included frequent job changes, long working hours, lack of rest time, and unpredictable job demands. The findings highlight that migrant workers in Korea face unique work-related difficulties which present barriers to exercise. © 2014 Wiley Periodicals, Inc.

  14. Stretching Safely and Effectively

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    ... shown that stretching immediately before an event weakens hamstring strength. Instead of static stretching, try performing a " ... If you play soccer, for instance, stretch your hamstrings as you're more vulnerable to hamstring strains. ...

  15. Team Size and Stretching-Exercise Effects on Simulated Chest Compression Performance and Exertion

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    Jessica C. Schoen

    2017-09-01

    Full Text Available Introduction: Investigators conducted a prospective experimental study to evaluate the effect of team size and recovery exercises on individual providers’ compression quality and exertion. Investigators hypothesized that 1 larger teams would perform higher quality compressions with less exertion per provider when compared to smaller teams; and 2 brief stretching and breathing exercises during rest periods would sustain compressor performance and mitigate fatigue. Methods: In Phase I, a volunteer cohort of pre-clinical medical students performed four minutes of continuous compressions on a Resusci-Anne manikin to gauge the spectrum of compressor performance in the subject population. Compression rate, depth, and chest recoil were measured. In Phase II, the highest-performing Phase I subjects were placed into 2-, 3-, and/or 4-compressor teams; 2-compressor teams were assigned either to control group (no recovery exercises or intervention group (recovery exercises during rest. All Phase II teams participated in 20-minute simulations with compressor rotation every two minutes. Investigators recorded compression quality and real-time heart rate data, and calculated caloric expenditure from contact heart rate monitor measurements using validated physiologic formulas. Results: Phase I subjects delivered compressions that were 24.9% (IQR1–3: [0.5%–74.1%] correct with a median rate of 112.0 (IQR1–3: [103.5–124.9] compressions per minute and depth of 47.2 (IQR1–3: [35.7–55.2] mm. In their first rotations, all Phase II subjects delivered compressions of similar quality and correctness (p=0.09. Bivariate analyses of 2-, 3-, and 4-compressor teams’ subject compression characteristics by subsequent rotation did not identify significant differences within or across teams. On multivariate analyses, only subjects in 2-compressor teams exhibited significantly lower compression rates (control subjects; p<0.01, diminished chest release (intervention

  16. Hemodynamic responses during and after multiple sets of stretching exercises performed with and without the Valsalva maneuver.

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    Lima, Tainah P; Farinatti, Paulo T V; Rubini, Ercole C; Silva, Elirez B; Monteiro, Walace D

    2015-05-01

    This study investigated the acute hemodynamic responses to multiple sets of passive stretching exercises performed with and without the Valsalva maneuver. Fifteen healthy men aged 21 to 29 years with poor flexibility performed stretching protocols comprising 10 sets of maximal passive unilateral hip flexion, sustained for 30 seconds with equal intervals between sets. Protocols without and with the Valsalva maneuver were applied in a random counterbalanced order, separated by 48-hour intervals. Hemodynamic responses were measured by photoplethysmography pre-exercise, during the stretching sets, and post-exercise. The effects of stretching sets on systolic and diastolic blood pressure were cumulative until the fourth set in protocols performed with and without the Valsalva maneuver. The heart rate and rate pressure product increased in both protocols, but no additive effect was observed due to the number of sets. Hemodynamic responses were always higher when stretching was performed with the Valsalva maneuver, causing an additional elevation in the rate pressure product. Multiple sets of unilateral hip flexion stretching significantly increased blood pressure, heart rate, and rate pressure product values. A cumulative effect of the number of sets occurred only for systolic and diastolic blood pressure, at least in the initial sets of the stretching protocols. The performance of the Valsalva maneuver intensified all hemodynamic responses, which resulted in significant increases in cardiac work during stretching exercises.

  17. Acute effect of passive rest intervals and stretching exercise on multiple set performance

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    Antonio Claudio do Rosário Souza

    2009-01-01

    Full Text Available http://dx.doi.org/10.5007/1980-0037.2009v11n4p435 The objective of this study was to determine the acute effect of passive rest intervals and static stretching between resistance exercise sets on the number of maximal repetitions (RM, rating of perceived exertion (RPE, and cumulative number of repetitions in multiple sets with a workload adjusted by the 8RM test. Fourteen trained male subjects (24.4 ± 2.1 years; 79.1 ± 7.1 kg; 175.4 ± 5.6 cm were studied. On the first two visits, the subjects were submitted to the test and 8RM re-test using chest press (CP and squat (SQ exercises. On the two subsequent visits, all subjects were randomly assigned to two experimental situations: a 8RM test with a passive rest interval (PI; b 8RM test with static stretching (SS. The subjects performed three sets of CP and SQ, intercalated with 2 minutes of passive rest or 30 seconds of static stretching. ANOVA revealed a significant decrease (p < 0.05 in the second (PI = 6 ± 0.8 x SS = 5.2 ± 1.0 repetitions and third (PI = 4.1 ± 0.8 X SS = 3.3 ± 0.6 repetitions sets for CP and only in the third set (PI = 4.9 ± 0.8 X SS = 4.2 ± 1.0 repetitions for SQ. For RPE, the Wilcoxon test showed significant differences (p < 0.05 between all sets for CP and SQ. For the cumulative number of repetitions, the paired t-test revealed a significant decrease (p < 0.05 for CP (PI = 18.3 ± 1.5 X SS = 16.8 ± 1.6 repetitions. These results indicate that static stretching between resistance exercise sets decreases 8RM test performance.

  18. Enhanced tolerance to stretch-induced performance degradation of stretchable MnO2-based supercapacitors.

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    Huang, Yan; Huang, Yang; Meng, Wenjun; Zhu, Minshen; Xue, Hongtao; Lee, Chun-Sing; Zhi, Chunyi

    2015-02-04

    The performance of many stretchable electronics, such as energy storage devices and strain sensors, is highly limited by the structural breakdown arising from the stretch imposed. In this article, we focus on a detailed study on materials matching between functional materials and their conductive substrate, as well as enhancement of the tolerance to stretch-induced performance degradation of stretchable supercapacitors, which are essential for the design of a stretchable device. It is revealed that, being widely utilized as the electrode material of the stretchable supercapacitor, metal oxides such as MnO2 nanosheets have serious strain-induced performance degradation due to their rigid structure. In comparison, with conducting polymers like a polypyrrole (PPy) film as the electrochemically active material, the performance of stretchable supercapacitors can be well preserved under strain. Therefore, a smart design is to combine PPy with MnO2 nanosheets to achieve enhanced tolerance to strain-induced performance degradation of MnO2-based supercapacitors, which is realized by fabricating an electrode of PPy-penetrated MnO2 nanosheets. The composite electrodes exhibit a remarkable enhanced tolerance to strain-induced performance degradation with well-preserved performance over 93% under strain. The detailed morphology and electrochemical impedance variations are investigated for the mechanism analyses. Our work presents a systematic investigation on the selection and matching of electrode materials for stretchable supercapacitors to achieve high performance and great tolerance to strain, which may guide the selection of functional materials and their substrate materials for the next-generation of stretchable electronics.

  19. The effects of an active-assisted stretching program on functional performance in elderly persons: A pilot study

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    Damian C Stanziano

    2009-03-01

    Full Text Available Damian C Stanziano1,2, Bernard A Roos1,2,3,4, Arlette C Perry1, Shenghan Lai5, Joseph F Signorile1,31Department of Exercise and Sport Sciences, University of Miami, Coral Gables, FL, USA; 2Stein Gerontological Institute, Miami Jewish Home and Hospital, Miami, FL, USA; 3Geriatric Research, Education, and Clinical Center, Miami VA Healthcare System, Miami, FL, USA; 4Departments of Medicine and Neurology, University of Miami Miller School of Medicine, Miami, FL, USA; 5Departments of Pathology and Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA Abstract: This study examined the impact of an eight-week active-assisted (AA stretching program on functionality, mobility, power, and range of motion (ROM in elderly residents of a residential retirement community. Seventeen volunteers (4 male, 13 female; 88.8 ± 5.36 years were randomly assigned to an AA or control group. The AA group performed 10 different AA stretches targeting the major joints of the body twice weekly for eight weeks. Controls attended classes requiring limited physical activity. All participants were assessed using four fl exibility and six functional tests, one week before and after the eight-week training period. A fully randomized repeated-measures ANCOVA with pretest scores as a covariate was used to detect differences between groups across time. The AA group demonstrated significant increases in ROM for most of the joints evaluated (p < 0.05 and significant increases in all performance measures (p < 0.05. Controls showed no improvements in functional or ROM measures (α = 0.05. Additionally, the AA group showed significantly better performance outcomes across the training period than controls. We conclude that our eight-week flexibility program effectively reduces age-related losses in ROM and improves functional performance in elderly persons with insufficient physical reserves to perform higher-intensity exercises.Keywords: proprioceptive neuromuscular

  20. Acute effects of static and dynamic stretching on jump performance after 15 min of reconditioning shooting phase in basketball players.

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    Annino, Giuseppe; Ruscello, Bruno; Lebone, Pietro; Palazzo, Francesco; Lombardo, Mauro; Padua, Elvira; Verdecchia, Luca; Tancredi, Virginia; Iellamo, Ferdinando

    2017-04-01

    The aim of this study was to assess the effects of static (SS) and dynamic stretching (DS) on vertical jump performance executed before, immediately after and at the end of the shooting phase (i.e., 15 min later), as to simulate the actual conditions preceding a match, in professional basketball players. Ten elite basketball players (age: 29±6.73 years, height: 194.67±7.75 cm, weight: 91±8.17 kg and BMI 23.8±7.91 kg.m-2) participated to the study. SS and DS protocols were administered during the first training session of the week, 48 hours after the championship match. Stretching protocols consisted in ~7 minutes of general warm-up phase followed by ~8 minutes of SS and DS, performed with a cross-over design., and ~15 minutes of a specific warm-up shooting phase (SP). Vertical jump tests consisted in counter movement jump (CMJ) and CMJ with arm swings (CMJas) and were performed immediately after the end of each stretching phase (preS, postS, postSP). A significant decrease (P=0.05; η2partial=0.29) in jumping tests height occurred in CMJas, when performed after the SS (i.e., PostS). However, no significant differences in jumping performances, occurred after the general warm phase and the specific warm-up shooting phase, between the two stretching protocols. These results would indicate that, overall, stretching routines either dynamic or static, performed before a basketball match are transient and affect only marginally leg muscles performance. Stretching routines, particularly the dynamic ones, may be useful to maintain muscle performance before a competition, provided that this latter begins shortly after.

  1. Group II muscle afferents probably contribute to the medium latency soleus stretch reflex during walking in humans

    DEFF Research Database (Denmark)

    Grey, Michael James; Ladouceur, Michel; Andersen, Jacob B.

    2001-01-01

    1. The objective of this study was to determine which afferents contribute to the medium latency response of the soleus stretch reflex resulting from an unexpected perturbation during human walking. 2. Fourteen healthy subjects walked on a treadmill at approximately 3.5 km h(-1) with the left ankle...... = 0.007), whereas the short latency component was unchanged (P = 0.653). 7. An ankle block with lidocaine hydrochloride was performed to suppress the cutaneous afferents of the foot and ankle. Neither the short (P = 0.453) nor medium (P = 0.310) latency reflexes were changed. 8. Our results support...

  2. Impact of 'stretch' targets for cardiovascular disease management within a local pay-for-performance programme.

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    Pape, Utz J; Huckvale, Kit; Car, Josip; Majeed, Azeem; Millett, Christopher

    2015-01-01

    Pay-for-performance programs are often aimed to improve the management of chronic diseases. We evaluate the impact of a local pay for performance programme (QOF+), which rewarded financially more ambitious quality targets ('stretch targets') than those used nationally in the Quality and Outcomes Framework (QOF). We focus on targets for intermediate outcomes in patients with cardiovascular disease and diabetes. A difference-in-difference approach is used to compare practice level achievements before and after the introduction of the local pay for performance program. In addition, we analysed patient-level data on exception reporting and intermediate outcomes utilizing an interrupted time series analysis. The local pay for performance program led to significantly higher target achievements (hypertension: p-value <0.001, coronary heart disease: p-values <0.001, diabetes: p-values <0.061, stroke: p-values <0.003). However, the increase was driven by higher rates of exception reporting (hypertension: p-value <0.001, coronary heart disease: p-values <0.03, diabetes: p-values <0.05) in patients with all conditions except for stroke. Exception reporting allows practitioners to exclude patients from target calculations if certain criteria are met, e.g. informed dissent of the patient for treatment. There were no statistically significant improvements in mean blood pressure, cholesterol or HbA1c levels. Thus, achievement of higher payment thresholds in the local pay for performance scheme was mainly attributed to increased exception reporting by practices with no discernable improvements in overall clinical quality. Hence, active monitoring of exception reporting should be considered when setting more ambitious quality targets. More generally, the study suggests a trade-off between additional incentive for better care and monitoring costs.

  3. Pre-Stretched Low Equivalent Weight PFSA Membranes with Improved Fuel Cell Performance

    DEFF Research Database (Denmark)

    Zhang, Wenjing (Angela); Wycisk, Ryszard; Kish, Daniel L.

    2014-01-01

    for the morphological changes to be permanent. For 825 EW PFSA, stretching increased the polymer crystallinity by 22.5%, with a reduction in methanol permeability and a small increase in proton conductivity. In direct methanol fuel cell tests at 60◦C with 1.0 M methanol, the power density at 0.4 V with a DR = 4...... stretched 825 EW membrane (72 mW/cm2) was considerably greater than that obtained with a solution-cast membrane (28 mW/cm2) or with a commercial Nafion 117 membrane (55 mW/cm2). For 733 EW PFSA, stretching promoted the formation of ordered ionic domains leading to an increase in proton conductivity...

  4. Velocities and joint angles during double backward stretched salto performed with stable landing and in combination with tempo salto

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    J Sadowski

    2009-07-01

    Full Text Available The aim of the study was to compare the values of velocity an joint angles obtained during performance of double salto backward stretched with a stable landing and its combination with salto tempo. Seven top level acrobats (track jumpers participated in study. Mean values of body height, mass and age had a value of: 170 cm ± 4.0 cm, 72.4 kg ± 3.6 kg, 20.4±1.7 years, respectively. The studies were conducted on a standard acrobatic path (type PTS 2000. Two digital video cameras (240 Hz and APAS 2000 (Ariel Dynamics Inc. were used during studies. Markers were placed in ankle, knee, hip, arm, elbow and wrist joints. All marker positions were tracked and reconstructed using the APAS system. Two sequences with the following elements were analysed: round-off - double salto backward stretched (A and round-off - double salto backward stretched - tempo salto (B. The highest differences between the key components describing performance of presented exercises exist for joint angles during launching and landing position, and resultant velocities during touchdown. In version A the athlete created prerequisites for “gliding” double salto backward stretched by means of the body segments motions, whereas in version B he executes faster motions of the body segments accentuating his actions upon backward rotation of the body. During the final phase of double salto backward stretched in combination with tempo salto the athlete performed courbette “under himself” (almost straight feet are placed in front of vertical line, pushes directly back and in 0,1 s executes stable arm swing upward-backward to tempo salto.

  5. High-performance Fuel Cell with Stretched Catalyst-Coated Membrane: One-step Formation of Cracked Electrode.

    Science.gov (United States)

    Kim, Sang Moon; Ahn, Chi-Yeong; Cho, Yong-Hun; Kim, Sungjun; Hwang, Wonchan; Jang, Segeun; Shin, Sungsoo; Lee, Gunhee; Sung, Yung-Eun; Choi, Mansoo

    2016-05-23

    We have achieved performance enhancement of polymer electrolyte membrane fuel cell (PEMFC) though crack generation on its electrodes. It is the first attempt to enhance the performance of PEMFC by using cracks which are generally considered as defects. The pre-defined, cracked electrode was generated by stretching a catalyst-coated Nafion membrane. With the strain-stress property of the membrane that is unique in the aspect of plastic deformation, membrane electrolyte assembly (MEA) was successfully incorporated into the fuel cell. Cracked electrodes with the variation of strain were investigated and electrochemically evaluated. Remarkably, mechanical stretching of catalyst-coated Nafion membrane led to a decrease in membrane resistance and an improvement in mass transport, which resulted in enhanced device performance.

  6. Strategic Groups and Banks’ Performance

    Directory of Open Access Journals (Sweden)

    Gregorz Halaj

    2009-06-01

    Full Text Available The theory of strategic groups predicts the existence of stable groups of companies that adopt similar business strategies. The theory also predicts that groups will differ in performance and in their reaction to external shocks. We use cluster analysis to identify strategic groups in the Polish banking sector. We find stable groups in the Polish banking sector constituted after the year 2000 following the major privatisation and ownership changes connected with transition to the mostly-privately-owned banking sector in the late 90s. Using panel regression methods we show that the allocation of banks to groups is statistically significant in explaining the profitability of banks. Thus, breaking down the banks into strategic groups and allowing for the different reaction of the groups to external shocks helps in a more accurate explanation of profits of the banking sector as a whole.Therefore, a more precise ex ante assessment of the loss absorption capabilities of banks is possible, which is crucial for an analysis of banking sector stability. However, we did not find evidence of the usefulness of strategic groups in explaining the quality of bank portfolios as measured by irregular loans over total loans, which is a more direct way to assess risks to financial stability.

  7. ACUTE EFFECTS OF STATIC STRETCHING, DYNAMIC EXERCISES, AND HIGH VOLUME UPPER EXTREMITY PLYOMETRIC ACTIVITY ON TENNIS SERVE PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Ertugrul Gelen

    2012-12-01

    Full Text Available The purpose of this study was to compare the acute effects of static stretching; dynamic exercises and high volume upper extremity plyometric activity on tennis serve performance. Twenty-six elite young tennis players (15.1 ± 4.2 years, 167.9 ± 5.8 cm and 61.6 ± 8.1 kg performed 4 different warm-up (WU routines in a random order on non-consecutive days. The WU methods consisted of traditional WU (jogging, rally and serve practice (TRAD; traditional WU and static stretching (TRSS; traditional WU and dynamic exercise (TRDE; and traditional WU and high volume upper extremity plyometric activity (TRPLYP. Following each WU session, subjects were tested on a tennis serve ball speed test. TRAD, TRSS, TRDE and TRPLYO were compared by repeated measurement analyses of variance and post-hoc comparisons. In this study a 1 to 3 percent increase in tennis serve ball speed was recorded in TRDE and TRPLYO when compared to TRAD (p 0.05. ICCs for ball speed showed strong reliability (0.82 to 0.93 for the ball speed measurements.The results of this study indicate that dynamic and high volume upper extremity plyometric WU activities are likely beneficial to serve speed of elite junior tennis players.

  8. Stretch Marks

    Science.gov (United States)

    ... completely without the help of a dermatologist or plastic surgeon. These doctors may use one of many types of treatments — from actual surgery to techniques like microdermabrasion and laser treatment — to reduce the appearance of stretch marks. These techniques are ...

  9. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS

    CERN Multimedia

    D. Acosta

    The global commissioning campaign begins this year with a series of weekly two-day global runs of limited participation until mid-March. The aim of these runs varies week-to-week, but includes the commissioning the calorimeter triggers, the muon track-finder triggers in the DT/CSC overlap, the PLL locking ranges, and generally accumulating data either for HCAL noise characterization or detector studies with cosmic muons. In mid-March a full Global Run is scheduled with all components participating, followed in April by a Cosmic Run with the aim of collecting statistics over a couple weeks with the installed Tracker and other subsystems. The ultimate milestone is the Cosmic Run At Four Tesla (CRAFT), with a completed CMS closed and the solenoid energized for data-taking during June. The Detector Performance Groups start the year with the focus to prepare for LHC collisions, and the associated challenges (CSA08) and global commissioning exercises (CRAFT) along the way. New this year is the addition of the Tri...

  10. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS

    CERN Multimedia

    D. Acosta

    The commissioning effort is presently addressing two main areas: the commissioning of the hardware components at the pit and the coordination of the activities of the newly constituted Detector Performance groups (DPGs). At point 5, a plan regarding the service cavern and the commissioning of the connections of the off-detector electronics (for the data collection line and trigger primitive generation) to the central DAQ and the central Trigger has been defined. This activity was started early February and will continue until May. It began with Tracker electronics followed so far by HCAL and CSC. The goal is to have by May every detector commission, as much as possible, their data transfer paths from FED to Central DAQ as well as their trigger setups between TPGs and Global Level 1 trigger. The next focus is on connections of front-ends to the service cavern. This depends strongly on the installations of services. Presently the only detector which has its link fibers connected to the off-detector electr...

  11. Comparing the effects of 3 weeks of upper-body vibration training, vibration and stretching, and stretching alone on shoulder flexibility in college-aged men.

    Science.gov (United States)

    Ferguson, Steven L; Kim, Eonho; Seo, Dong-Il; Bemben, Michael G

    2013-12-01

    This study compared the effects of 3 weeks of upper-body vibration training, vibration and stretching, and stretching alone on shoulder flexibility in college-aged men. Twenty-one men were randomly assigned to vibration-stretching (VS; n = 8), vibration only (VO; n = 6), or stretching only (SO; n = 7) groups that trained 3 times per week for 3 weeks. All 3 groups performed 9 total sets of 30-second stretches. The VS group performed four 30-second upper-body vibration exercises and five 30-second upper-body stretching exercises. The VO group performed nine 30-second upper-body vibration exercises. The SO group performed nine 30-second upper-body stretching exercises. Shoulder flexion (SF), shoulder extension (SE), and shoulder transverse extension (STE) were assessed by a Leighton Flexometer and back scratch tests bilaterally (BSR, BSL) were measured via tape measure. A 1-way analysis of variance (ANOVA) evaluated groups at baseline and a 2-way repeated-measures ANOVA evaluated the interventions over time. At baseline, there were no group differences in age, height, or weight. There was a significant (p alone or combined with stretching, is a viable alternative to a standard stretching routine when attempting to increase shoulder flexibility. Adding vibration training to a flexibility regimen may improve the likelihood of regularly performing flexibility sessions because of increased variety.

  12. Performance Assessment National Review Group

    International Nuclear Information System (INIS)

    Lieberman, J.A.; Davis, S.N.; Harleman, D.R.F.

    1985-02-01

    Performance assessment involves predicting the potential radiological impact of a nuclear waste disposal system, taking into account all of the natural and engineered components of the system. It includes the analysis and evaluation of predicted system and component performance to determine compliance with regulatory performance criteria. In the context of the nuclear waste management program, performance assessment has five major purposes: to assist in the evaluation and selection of repository sites; to guide the research, development, and testing programs; to assist in the evaluation of repository designs; to assist in the evaluation of the design and performance of engineered barriers; and to show regulatory compliance and support repository licensing. Current performance assessment methodologies are still in the developmental stage. Only the simplest of bounding calculations have produced quantitative predictions of radionuclide releases. The methodologies require considerable extension and validation before they can provide answers suitable for project decisions and licensing. 135 refs., 9 figs., 1 tab

  13. Group performance and group learning at dynamic system control tasks

    International Nuclear Information System (INIS)

    Drewes, Sylvana

    2013-01-01

    Proper management of dynamic systems (e.g. cooling systems of nuclear power plants or production and warehousing) is important to ensure public safety and economic success. So far, research has provided broad evidence for systematic shortcomings in individuals' control performance of dynamic systems. This research aims to investigate whether groups manifest synergy (Larson, 2010) and outperform individuals and if so, what processes lead to these performance advantages. In three experiments - including simulations of a nuclear power plant and a business setting - I compare the control performance of three-person-groups to the average individual performance and to nominal groups (N = 105 groups per experiment). The nominal group condition captures the statistical advantage of aggregated group judgements not due to social interaction. First, results show a superior performance of groups compared to individuals. Second, a meta-analysis across all three experiments shows interaction-based process gains in dynamic control tasks: Interacting groups outperform the average individual performance as well as the nominal group performance. Third, group interaction leads to stable individual improvements of group members that exceed practice effects. In sum, these results provide the first unequivocal evidence for interaction-based performance gains of groups in dynamic control tasks and imply that employers should rely on groups to provide opportunities for individual learning and to foster dynamic system control at its best.

  14. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS

    CERN Document Server

    T. Camporesi

    P5 Commissioning activities The commissioning effort at the pit has made major progress since the last CMS week concerning the installation and operation of the off-detector electronics in USC. The progress has been much slower in the experi¬mental cavern due to the delay in the deployment of the infrastructure which should eventually allow safe powering-up of the front ends. Nevertheless, temporary power connections have allowed operation of slices of subdetectors at any given time. HF, HE, ECAL, DTs, RPCs and CSCs have carried out local commissioning tests with these temporary services. The status of hardware deployment in USC and on the towers/balconies is represented in the detailed table below.   Table 1: Status of installation of off-detector electronics. FEDs are detector dependent hardware modules which perform the first ‘colla¬tion’ of front-end data and send it to Central-data for event building. Tracker, ECAL, HCAL have their front end electronics mo...

  15. ABO Blood Group And Reproductive Performance | Gharoro ...

    African Journals Online (AJOL)

    ABO Blood Group And Reproductive Performance. ... Blood group A phenotype constituted 22.48%, while AB, B, and O blood groups made up 1.94, 15.28 and 60.3 percent respectively. The mean age of the ... Keywords: ABO Blood Group, Reproductive performance, population mapping, gene frequency. Journal of Mining ...

  16. Effects of special composite stretching on the swing of amateur golf players.

    Science.gov (United States)

    Lee, Joong-Chul; Lee, Sung-Wan; Yeo, Yun-Ghi; Park, Gi Duck

    2015-04-01

    [Purpose] The study investigated stretching for safer a golf swing compared to present stretching methods for proper swings in order to examine the effects of stretching exercises on golf swings. [Subjects] The subjects were 20 amateur golf club members who were divided into two groups: an experimental group which performed stretching, and a control group which did not. The subjects had no bone deformity, muscle weakness, muscle soreness, or neurological problems. [Methods] A swing analyzer and a ROM measuring instrument were used as the measuring tools. The swing analyzer was a GS400-golf hit ball analyzer (Korea) and the ROM measuring instrument was a goniometer (Korea). [Results] The experimental group showed a statistically significant improvement in driving distance. After the special stretching training for golf, a statistically significant difference in hit-ball direction deviation after swings were found between the groups. The experimental group showed statistically significant decreases in hit ball direction deviation. After the special stretching training for golf, statistically significant differences in hit-ball speed were found between the groups. The experimental group showed significant increases in hit-ball speed. [Conclusion] To examine the effects of a special stretching program for golf on golf swing-related factors, 20 male amateur golf club members performed a 12-week stretching training program. After the golf stretching training, statistically significant differences were found between the groups in hit-ball driving distance, direction deviation, deflection distance, and speed.

  17. Acute effect of different stretching methods on isometric muscle strength

    Directory of Open Access Journals (Sweden)

    Gabriel Vasconcellos de Lima Costa e Silva

    2014-03-01

    This study investigated the acute effect of static stretching methods (SS and proprioceptive neuromuscular facilitation (PNF on the static muscle strength (SMS. Eleven young male subjects with strength training experience, performed 3 tests with a 48h interval between them, randomly selected, where each one subject carried out all procedures: a hand grip without stretching; b hand grip preceded by static stretching of wrist flexors muscles; c hand grip preceded by PNF stretching of wrist flexors muscles. The Shapiro-Wilk test verified the normality of data, and a one-way ANOVA with repeated measures, followed by Tukey’s post hoc test, evaluated the differences between the groups. The significance was set at p 0.05. In conclusion, both stretching methods had caused negative effects on isometric strength, reducing its levels.

  18. Intraplaque stretch in carotid atherosclerotic plaque--an effective biomechanical predictor for subsequent cerebrovascular ischemic events.

    Directory of Open Access Journals (Sweden)

    Zhongzhao Teng

    Full Text Available BACKGROUND: Stretch is a mechanical parameter, which has been proposed previously to affect the biological activities in different tissues. This study explored its utility in determining plaque vulnerability. METHODS: One hundred and six patients with mild to moderate carotid stenosis were recruited in this study (53 symptomatic and 53 asymptomatic. High resolution, multi-sequence magnetic resonance (MR imaging was performed to delineate various plaque components. Finite element method was used to predict high stretch concentration within the plaque. RESULTS: During a two-year follow-up, 11 patients in symptomatic group and 3 in asymptomatic group experienced recurrent cerebrovascular events. Plaque stretch at systole and stretch variation during one cardiac cycle was greater in symptomatic group than those in the asymptomatic. Within the symptomatic group, a similar trend was observed in patients with recurrent events compared to those without. CONCLUSION: Plaques with high stretch concentration and large stretch variation are associated with increased risk of future cerebrovascular events.

  19. Stretch Sensor Device

    DEFF Research Database (Denmark)

    2013-01-01

    The invention relates to a method for determining stretch values and movement of body parts, e.g. a foot, by analysing stretch data from a stretch sensor. By analysing data from the stretch sensor it is possible to determine stretch samples which are associated with particular motion phases...

  20. Encounter Group Effects of Soccer Team Performance.

    Science.gov (United States)

    Magen, Zipora

    1980-01-01

    Suggests that a positive relationship exists between encounter group experience and the soccer team performance--a conclusion worthy of consideration in further research in the fields of psychology and sociology of sports. (Author)

  1. Differences in the performance tests of the fast and slow stretch and shortening cycle among professional, amateur and elite youth soccer players

    OpenAIRE

    Keiner, Michael; Sander, Andre; Wirth, Klaus; Hartmann, Hagen

    2015-01-01

    The purpose of this study was to establish whether physical attributes can differentiate between professional, amateur and elite youth soccer players; such a distinction could aid in the selection process for youth soccer. Therefore, this investigation evaluated a suspected difference in the performance tests of the slow and fast stretch and the shortening cycle (squat jump [SJ], countermovement jump [CMJ], and drop jump from varying heights [DJ]) among professional, amateur and elite youth s...

  2. Guia prático de excercícios de alongamento como promotor de autonômia em um grupo de mulheres / Promoting autonomy in a group of women with a practical guide to stretching

    Directory of Open Access Journals (Sweden)

    Tialhes Farias Marconato

    2018-04-01

    Full Text Available A Terapia Ocupacional desenvolve sua prática e estudo sobre as atividades humanas com a utilização de recursos e instrumentos terapêuticos, que podem beneficiar o processo de envelhecimento. Nesse sentido, o estudo visou reconhecer e descrever a percepção de mulheres com idade entre 40 e 60 anos de idade, participantes de um grupo de Terapia Ocupacional, quanto às repercussões da utilização de um Guia Prático de Alongamento, no desempenho das atividades cotidianas. Para tanto, realizou-se uma pesquisa qualitativa, exploratória e descritiva, por meio de Grupo Focal. Verificou-se que a utilização do Guia influenciou no controle da dor, na autonomia para realização de atividades de vida diária e na percepção do próprio corpo das participantes do estudo. Conclui-se que o Guia Prático de Alongamento é uma ferramenta simples, porém relevante para melhorar a consciência corporal, a autonomia e independência de indivíduos em processo de envelhecimento, sugerindo-o como um instrumento indicado para outras populações. AbstractOccupational Therapy carries out the practice and study of human activities by employing therapeutic resources and instruments, which can benefit the aging process. Thus, the aim of this study was to identify and describe the perception of women between the ages of 40 and 60 in an Occupational Therapy group regarding the effects of using a Practical Guide to Stretching on the performance of their daily activities. In that sense, a qualitative, exploratory and descriptive Focus Group research was carried out. It was verified that the use of the Practical Guide had an influence on participants’ pain control, autonomy to perform daily activities and body perception. It was concluded that the Practical Guide to Stretching is a simple but relevant tool that helps aging individuals improve their body awareness, autonomy and independence. It is also a suitable tool for other populations.Keywords: Muscle

  3. Effects of Static Stretching and Playing Soccer on Knee Laxity.

    Science.gov (United States)

    Baumgart, Christian; Gokeler, Alli; Donath, Lars; Hoppe, Matthias W; Freiwald, Jürgen

    2015-11-01

    This study investigated exercise-induced effects of static stretching and playing soccer on anterior tibial translation (ATT) of the knee joint. Randomized controlled trial. University biomechanics laboratory. Thirty-one athletes were randomly assigned into a stretching (26.9 ± 6.2 years, 1.77 ± 0.09 m, 67.9 ± 10.7 kg) and a control group (27.9 ± 7.4 years, 1.75 ± 0.08 m, 72.0 ± 14.9 kg). Thirty-one amateur soccer players in an additional soccer group (25.1 ± 5.6 years, 1.74 ± 0.10 m, 71.8 ± 14.8 kg). All participants had no history of knee injury requiring surgery and any previous knee ligament or cartilage injury. The stretching group performed 4 different static stretching exercises with a duration of 2 × 20 seconds interspersed with breaks of 10 seconds. The soccer group completed a 90-minute soccer-specific training program. The control group did not perform any physical activity for approximately 30 minutes. Anterior tibial translation was measured with the KT-1000 knee arthrometer at forces of 67 N, 89 N, and maximal manual force (Max) before and after the intervention. There was a significant increase in ATT after static stretching and playing soccer at all applied forces. Maximal manual testing revealed a mean increase of ATT after static stretching of 2.1 ± 1.6 mm (P soccer of 1.0 ± 1.5 mm (P = 0.001). The ATT increase after static stretching at 67 and 89 N is significantly higher than in controls. At maximum manual testing, significant differences were evident between all groups. Static stretching and playing soccer increase ATT and may consequently influence mechanical factors of the anterior cruciate ligament. The ATT increase after static stretching was greater than after playing soccer. The observed increase in ATT after static stretching and playing soccer may be associated with changes in kinesthetic perception and sensorimotor control, activation of muscles, joint stability, overall performance, and higher injury risk.

  4. Autonomie du groupe restreint et performance

    Directory of Open Access Journals (Sweden)

    Elke Nissen

    2005-09-01

    Full Text Available Un groupe est autonome lorsqu'il prend lui-même en charge sa gestion (Abric, 1996 et lorsque celle-ci fonctionne bien. L'autonomie du groupe restreint est une caractéristique revendiquée dans le cadre actuel de l'expansion de dispositifs collaboratifs à distance entre apprenants. La question qui se pose alors est de savoir si un groupe restreint autonome est plus performant qu'un groupe moins autonome. L'autonomie d'un groupe d'apprentissage en ligne est-elle en relation avec la qualité de la réalisation de la tâche ? Est-elle en relation avec les progrès réalisés par les membres du groupe ? Dans le cadre de notre étude expérimentale, menée dans deux dispositifs pédagogiques différents (l'environnement d'apprentissage Babbelnet et une formation sur la plate-forme Acolad, des étudiants ont réalisé en groupes restreints, avec l'accompagnement d'un tuteur, une tâche de type actionnel – en l'occurrence une rédaction en langue étrangère (allemand ou anglais. Pour ce faire, ils disposaient d'aides méthodologiques et linguistiques dans l'environnement pédagogique en ligne. Ils ont interagi par le biais d'Internet au moyen de différents outils de communication. Une analyse de l'interaction qui a eu lieu dans chaque groupe, l'évaluation des rédactions réalisées conjointement, deux tests réalisés respectivement avant et après la phase de travail en groupe ainsi qu'un formulaire auto-administré nous permettent de mettre en lien l'autonomie des groupes, d'une part, et leur performance, voire leur apprentissage, d'autre part. Au vu de cette étude, il apparaît que l'autonomie du groupe n'a pas d'influence directe sur l'apprentissage des groupes restreints. En revanche, un rapport est visible entre l'appréciation du fonctionnement du groupe par ses membres et l'évolution de la performance des groupes.

  5. EFFECTS OF DYNAMIC AND STATIC STRETCHING WITHIN GENERAL AND ACTIVITY SPECIFIC WARM-UP PROTOCOLS

    Directory of Open Access Journals (Sweden)

    Michael Samson

    2012-06-01

    Full Text Available The purpose of the study was to determine the effects of static and dynamic stretching protocols within general and activity specific warm-ups. Nine male and ten female subjects were tested under four warm-up conditions including a 1 general aerobic warm-up with static stretching, 2 general aerobic warm-up with dynamic stretching, 3 general and specific warm-up with static stretching and 4 general and specific warm-up with dynamic stretching. Following all conditions, subjects were tested for movement time (kicking movement of leg over 0.5 m distance, countermovement jump height, sit and reach flexibility and 6 repetitions of 20 metre sprints. Results indicated that when a sport specific warm-up was included, there was an 0.94% improvement (p = 0.0013 in 20 meter sprint time with both the dynamic and static stretch groups. No such difference in sprint performance between dynamic and static stretch groups existed in the absence of the sport specific warm-up. The static stretch condition increased sit and reach range of motion (ROM by 2.8% more (p = 0.0083 than the dynamic condition. These results would support the use of static stretching within an activity specific warm-up to ensure maximal ROM along with an enhancement in sprint performance

  6. Members' needs, intragroup conflict, and group performance.

    Science.gov (United States)

    Chun, Jinseok S; Choi, Jin Nam

    2014-05-01

    Focusing on "what people want in their group" as a critical antecedent of intragroup conflict, the present study theorizes and empirically investigates the relationships among the psychological needs of group members, intragroup conflict, and group performance. It attends to the within-group average and dispersion of members' psychological needs and examines the effects stemming from group composition of needs on multiple types of conflict. The analyses based on multisource data from 145 organizational teams revealed significant relationships between the groups' composition with respect to the members' need for achievement and task conflict, need for affiliation and relationship conflict, and need for power and status conflict. Some of these relationships were moderated by open communication among members. The analyses also demonstrated that when the 3 types of conflict were considered together, task conflict was a positive predictor of group performance, whereas relationship conflict was a negative predictor. The findings highlight the motivational aspects of intragroup conflict, revealing the multilevel dynamics of the psychological needs in social settings. (c) 2014 APA, all rights reserved.

  7. A Japanese Stretching Intervention Can Modify Lumbar Lordosis Curvature.

    Science.gov (United States)

    Kadono, Norio; Tsuchiya, Kazushi; Uematsu, Azusa; Kamoshita, Hiroshi; Kiryu, Kazunori; Hortobágyi, Tibor; Suzuki, Shuji

    2017-08-01

    Eighteen healthy male adults were assigned to either an intervention or control group. Isogai dynamic therapy (IDT) is one of Japanese stretching interventions and has been practiced for over 70 years. However, its scientific quantitative evidence remains unestablished. The objective of this study was to determine whether IDT could modify lumbar curvature in healthy young adults compared with stretching exercises used currently in clinical practice. None of previous studies have provided data that conventional stretching interventions could modify spinal curvatures. However, this study provides the first evidence that a specific form of a Japanese stretching intervention can acutely modify the spinal curvatures. We compared the effects of IDT, a Japanese stretching intervention (n=9 males), with a conventional stretching routine (n=9 males) used widely in clinics to modify pelvic tilt and lumbar lordosis (LL) angle. We measured thoracic kyphosis (TK) and LL angles 3 times during erect standing using the Spinal Mouse before and after each intervention. IDT consisted of: (1) hip joint correction, (2) pelvic tilt correction, (3) lumbar alignment correction, and (4) squat exercise stretch. The control group performed hamstring stretches while (1) standing and (2) sitting. IDT increased LL angle to 25.1 degrees (±5.9) from 21.2 degrees (±6.9) (P=0.047) without changing TK angle (pretest: 36.8 degrees [±6.9]; posttest: 36.1 degrees [±6.5]) (P=0.572). The control group showed no changes in TK (P=0.819) and LL angles (P=0.744). IDT can thus be effective for increasing LL angle, hence anterior pelvic tilt. Such modifications could ameliorate low back pain and improve mobility in old adults with an unfavorable pelvic position.

  8. Comparison of the Effects of Local Cryotherapy and Passive Cross-Body Stretch on Extensibility in Subjects with Posterior Shoulder Tightness

    Directory of Open Access Journals (Sweden)

    Kyue-nam Park

    2014-03-01

    Full Text Available The objective was to compare the immediate effects of local cryotherapy (LC and passive cross-body stretch on the extensibility of the posterior shoulder muscle in individuals with posterior shoulder tightness. Eighty-seven healthy subjects with a between-shoulder difference in internal rotation (IR range of motion (ROM greater than 10° were randomly divided into three groups: LC group, stretching group, and control group (n = 29 in each group. Subjects in the LC group received LC on infraspinatus and posterior deltoid muscles and subjects in the stretching group performed passive cross-body stretch. Stretch sensation was measured at the end range of passive IR and horizontal adduction (HA using numerical rating scale, and the pressure pain threshold (PPT at the infraspinatus and posterior deltoid muscles was measured using pressure algometry. Passive and active ROM of IR and HA of the glenohumeral joint were measured using an inclinometer. All measurements were performed at pre-intervention, post- intervention, and 10-min follow-up. Stretch sensation was significantly decreased and PPT was significantly increased in the LC and stretching groups at post-intervention, and these effects were maintained at 10-min follow-up, compared to the control group. Both the LC group and stretching group had a significantly greater increase in passive and active ROM of IR and HA, compared to the control group at post-intervention and 10-min follow-up. However, there were no significant differences in stretch sensation, PPT, or ROM of IR and HA between the LC group and stretching group. LC can be used to decrease the stretch sensation and increase PPT and ROM of IR and HA as much as a stretching exercise. LC could be an alternative method for increasing the restricted ROM of glenohumeral IR and HA for individuals with posterior shoulder tightness, especially for patients and sports players who have severe stretching discomfort.

  9. Reports from the Combined Performance Working Groups

    CERN Multimedia

    S. Haywood

    The main goal of the Combined Performance Groups is to study the detector performance for physics, as well as to monitor the effect of changes to the detector layout and the evolution of the software. The groups combine the expertise available in several different subdetectors. In addition, they are responsible for developing combined reconstruction algorithms and are involved in the calibration of energy scales and optimising resolutions. For the Workshop, the four groups made a real effort to compare the reconstruction in Athena (the "New" C++ software framework) and Atrecon (the "Old" software used for the TDR studies). b-tagging Working Group: Over the last few months, the description of the Inner Detector in the simulation has become more realistic, following the evolution of the detector design. This has caused the amount of material in the simulation to increase and the Pixel B-layer has been moved to a larger radius to allow for a wider beam-pipe. Nevertheless, the good performance of the b-tagging (...

  10. Comparison between static stretching and the Pilates method on the flexibility of older women.

    Science.gov (United States)

    Oliveira, Laís Campos de; Oliveira, Raphael Gonçalves de; Pires-Oliveira, Deise Aparecida de Almeida

    2016-10-01

    Flexibility decreases with advancing age and some forms of exercise, such as static stretching and Pilates, can contribute to the improvement of this physical ability. To compare the effects of static stretching and Pilates on the flexibility of healthy older women, over the age of 60 years. Thirty-two volunteers were randomized into two groups (Static stretching or Pilates) to perform exercises for 60 min, twice a week, for three months. Evaluations to analyze the movements of the trunk (flexion and extension), hip flexion and plantar and dorsiflexion of the ankle were performed before and after the intervention, using a fleximeter. The static stretching exercises improved the trunk flexion and hip flexion movements, while the Pilates improved all evaluated movements. However, over time, the groups presented differences only for the trunk extension movement. For some body segments, Pilates may be more effective for improving flexibility in older women compared to static stretching. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Acute Effects of Static Stretching of Hamstring on Performance and Anterior Cruciate Ligament Injury Risk During Stop-Jump and Cutting Tasks in Female Athletes.

    Science.gov (United States)

    Ruan, Mianfang; Zhang, Qiang; Wu, Xie

    2017-05-01

    Ruan, M, Zhang, Q, and Wu, X. Acute effects of static stretching of hamstring on performance and anterior cruciate ligament injury risk during stop-jump and cutting tasks in female athletes. J Strength Cond Res 31(5): 1241-1250, 2017-There is limited research investigating antagonist stretch. The purpose of this study was to evaluate the influence of static stretching of hamstrings (SSH) on performance and anterior cruciate ligament (ACL) injury risk during stop-jump and 180° cutting tasks. Twelve female college athletes (age 20.8 ± 0.7 years; height 1.61 ± 0.05 m; mass 54.25 ± 4.22 kg) participated in this study. Subjects performed stop-jump and 180° cutting tasks under 2 conditions: after warm-up with 4 × 30 seconds SSH or after warm-up without SSH. Three-dimensional kinematic and kinetic data as well as electromyography of biceps femoris, rectus femoris, vastus medialis, and gastrocnemius medialis were collected during testing. Static stretching of hamstrings significantly enhanced jump height by 5.1% (p = 0.009) but did not change the takeoff speed of cutting. No significant changes in peak knee adduction moment or peak anterior tibia shear force were observed with SSH regardless of the task. The peak lateral tibia shear force during cutting was significantly (p = 0.036) reduced with SSH. The co-contraction of hamstring and quadriceps during the preactivation (stop-jump: p = 0.04; cutting: p = 0.05) and downward phases (stop-jump: p = 0.04; cutting: p = 0.05) was significantly reduced after SSH regardless of the task. The results suggest that SSH enhanced the performance of stop-jump because of decreased co-contraction of hamstring and quadriceps but did not change the performance of cutting. In addition, SSH did not increase ACL injury risk during stop-jump and cutting tasks and even reduced medial-lateral knee loading during cutting.

  12. Comparison of the effects of local cryotherapy and passive cross-body stretch on extensibility in subjects with posterior shoulder tightness.

    Science.gov (United States)

    Park, Kyue-Nam; Kwon, Oh-Yun; Weon, Jong-Hyuck; Choung, Sung-Dae; Kim, Si-Hyun

    2014-01-01

    The objective was to compare the immediate effects of local cryotherapy (LC) and passive cross-body stretch on the extensibility of the posterior shoulder muscle in individuals with posterior shoulder tightness. Eighty-seven healthy subjects with a between-shoulder difference in internal rotation (IR) range of motion (ROM) greater than 10° were randomly divided into three groups: LC group, stretching group, and control group (n = 29 in each group). Subjects in the LC group received LC on infraspinatus and posterior deltoid muscles and subjects in the stretching group performed passive cross-body stretch. Stretch sensation was measured at the end range of passive IR and horizontal adduction (HA) using numerical rating scale, and the pressure pain threshold (PPT) at the infraspinatus and posterior deltoid muscles was measured using pressure algometry. Passive and active ROM of IR and HA of the glenohumeral joint were measured using an inclinometer. All measurements were performed at pre-intervention, post- intervention, and 10-min follow-up. Stretch sensation was significantly decreased and PPT was significantly increased in the LC and stretching groups at post-intervention, and these effects were maintained at 10-min follow-up, compared to the control group. Both the LC group and stretching group had a significantly greater increase in passive and active ROM of IR and HA, compared to the control group at post-intervention and 10-min follow-up. However, there were no significant differences in stretch sensation, PPT, or ROM of IR and HA between the LC group and stretching group. LC can be used to decrease the stretch sensation and increase PPT and ROM of IR and HA as much as a stretching exercise. LC could be an alternative method for increasing the restricted ROM of glenohumeral IR and HA for individuals with posterior shoulder tightness, especially for patients and sports players who have severe stretching discomfort. Key PointsLocal cryotherapy (LC) decreased the

  13. Local and Systemic Changes in Pain Sensitivity After 4 Weeks of Calf Muscle Stretching in a Nonpainful Population

    DEFF Research Database (Denmark)

    Bartholdy, Cecilie; Zangger, Graziella; Hansen, Lisbeth

    2016-01-01

    BACKGROUND: Stretching is often used in clinical practice for a variety of purposes, including pain therapy. The possible mechanism behind the effect of stretching remains to be clarified. AIM: To investigate whether 4 weeks of unilateral stretching of the calf muscles would affect local...... and central pain sensitivity. METHOD: This study was a randomized assessor-blinded clinical study. Healthy participants (age 18 to 40) were included and randomized. Participants in the intervention group were instructed to perform 2 stretching exercises targeting the calf muscles; 3 times 30 seconds, 7 days...... a week for 4 weeks on the dominant leg. Participants in the control group were instructed not to do any stretching for 4 weeks. Pressure pain threshold (PPT) and temporal summation (TS) of pressure pain were measured on the stretched calf, the contra-lateral calf, and contra-lateral lower arm using...

  14. A comparison of two stretching programs for hamstring muscles: A randomized controlled assessor-blinded study.

    Science.gov (United States)

    Demoulin, Christophe; Wolfs, Sébastien; Chevalier, Madeline; Granado, Caroline; Grosdent, Stéphanie; Depas, Yannick; Roussel, Nathalie; Hage, Renaud; Vanderthommen, Marc

    2016-01-01

    Most parameters regarding hamstring flexibility training programs have been investigated; however, the joint (i.e. hip or knee) on which the stretching should preferentially be focused needs to be further explored. This randomized controlled assessor-blinded study aimed to investigate the influence of this parameter. We randomly assigned 111 asymptomatic participants with tight hamstring muscles in three groups: a control group and two groups following a different home-based 8-week (five 10-minute sessions per week) hamstring stretching program (i.e. stretching performed by flexing the hip while keeping the knee extended [SH] or by first flexing the hip with a flexed knee and then extending the knee [SK]). Range of motion (ROM) of hip flexion and knee extension were measured before and after the stretching program by means of the straight leg raising test and the passive knee extension angle test, respectively. Eighty-nine participants completed the study. A significant increase in ROM was observed at post-test. Analyses showed significant group-by-time interactions for changes regarding all outcomes. Whereas the increase in hip flexion and knee extension ROM was higher in the stretching groups than in the CG (especially for the SH group p 0.05). In conclusion, the fact that both stretching programs resulted in similar results suggests no influence of the joint at which the stretching is focused upon, as assessed by the straight leg raising and knee extension angle tests.

  15. Knotting in stretched polygons

    International Nuclear Information System (INIS)

    Rensburg, E J Janse van; Orlandini, E; Tesi, M C; Whittington, S G

    2008-01-01

    The knotting in a lattice polygon model of ring polymers is examined when a stretching force is applied to the polygon. By examining the incidence of cut-planes in the polygon, we prove a pattern theorem in the stretching regime for large applied forces. This theorem can be used to examine the incidence of entanglements such as knotting and writhing. In particular, we prove that for arbitrarily large positive, but finite, values of the stretching force, the probability that a stretched polygon is knotted approaches 1 as the length of the polygon increases. In the case of writhing, we prove that for stretched polygons of length n, and for every function f(n)=o(√n), the probability that the absolute value of the mean writhe is less than f(n) approaches 0 as n → ∞, for sufficiently large values of the applied stretching force

  16. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS (DPG)

    CERN Multimedia

    Darin Acosta

    The pace of activity is high for the Detector Performance Groups now that the CMS experiment is complete for 2008 and LHC beams are imminent. This includes refinement of the data quality monitoring tools (including prompt offline analyses), triggers, reconstruction code, and calibration and alignment conditions. Notable since the last CMS Week has been the inclusion of the strip tracker into the global running in July and the inclusion of the pixel systems and ECAL endcaps in August. The following describes the highlights from each group. During the CRUZET3 global run in July (the third installment of the Cosmic Run at Zero Tesla exercise) the Silicon Strip tracker recorded data with all barrel detectors and one side of the end-cap wheels. The week-long data-taking period delivered about 300k tracks good for detector alignment and was an extremely valuable experience to test the reconstruction, calibration and alignment workflows in their final configuration. Events with tracks were selected in real-time at ...

  17. Transient filament stretching rheometer II

    DEFF Research Database (Denmark)

    Kolte, Mette Irene; Rasmussen, Henrik K.; Hassager, Ole

    1997-01-01

    The Lagrangian sspecification is used to simulate the transient stretching filament rheometer. Simulations are performed for dilute PIB-solutions modeled as a four mode Oldroyd-B fluid and a semidilute PIB-solution modeled as a non-linear single integral equation. The simulations are compared...

  18. Influence of acute static stretching on the behavior of maximum muscle strength

    Directory of Open Access Journals (Sweden)

    Carmen Lúcia Borges Bastos

    2014-06-01

    Full Text Available The aim of this study was to compare the influence of acute static stretching on maximal muscle strength (1RM. The non-probabilistic sample consisted of 30 subjects split into two groups: static stretching (SS= 15 and without stretching group (WS= 15. Muscle strength evaluation (1RM was conducted with a Dynamometer model 32527pp400 Pound push / pull devices coupled in knee extension (KE and bench press (BP. The Wilcoxon test for intragroup comparisons and the Kruskal-Wallis test for comparisons between groups (p< 0.05 were selected. There were no significant differences (p> 0.05 between the SS and WS in exercise KE and BP. Therefore, it can be concluded that there was no reduction in the performance of 1RM performing the exercises KE and BP when preceded by static stretching.

  19. [Current trends in the effects of stretching: application to physical exercise in the workplace].

    Science.gov (United States)

    Eguchi, Yasumasa; Ohta, Masanori; Yamato, Hiroshi

    2011-09-01

    A review of the Survey on the State of Employees' Health by the Ministry of Health, Labour and Welfare (2008) shows that the most commonly implemented aspect as an activity of worksite health promotion is "Health counseling", and the second is "Workplace physical exercise." Physical exercise, "Taiso", is acceptable and sustainable for workers, as it is easy to do in a group or alone. Various modes of stretching are implemented for workplace physical exercise. However, articles suggesting negative or contradictory effects of stretching have increased in recent years. Several review articles have revealed that static stretching may induce impairments of muscle power performance and no stretching will prevent or reduce muscle soreness after exercise. There are various aims of workplace physical exercise, so we have to consider the situational method when we apply stretching to occupational health.

  20. Acute Effect of Different Combined Stretching Methods on Acceleration and Speed in Soccer Players

    Directory of Open Access Journals (Sweden)

    Amiri-Khorasani Mohammadtaghi

    2016-04-01

    Full Text Available The purpose of this study was to investigate the acute effect of different stretching methods, during a warm-up, on the acceleration and speed of soccer players. The acceleration performance of 20 collegiate soccer players (body height: 177.25 ± 5.31 cm; body mass: 65.10 ± 5.62 kg; age: 16.85 ± 0.87 years; BMI: 20.70 ± 5.54; experience: 8.46 ± 1.49 years was evaluated after different warm-up procedures, using 10 and 20 m tests. Subjects performed five types of a warm-up: static, dynamic, combined static + dynamic, combined dynamic + static, and no-stretching. Subjects were divided into five groups. Each group performed five different warm-up protocols in five non-consecutive days. The warm-up protocol used for each group was randomly assigned. The protocols consisted of 4 min jogging, a 1 min stretching program (except for the no-stretching protocol, and 2 min rest periods, followed by the 10 and 20 m sprint test, on the same day. The current findings showed significant differences in the 10 and 20 m tests after dynamic stretching compared with static, combined, and no-stretching protocols. There were also significant differences between the combined stretching compared with static and no-stretching protocols. We concluded that soccer players performed better with respect to acceleration and speed, after dynamic and combined stretching, as they were able to produce more force for a faster execution.

  1. The Acute Effects of Upper Extremity Stretching on Throwing Velocity in Baseball Throwers

    Directory of Open Access Journals (Sweden)

    Michael Williams

    2013-01-01

    Full Text Available Purpose. To examine the effects of static and proprioceptive neuromuscular facilitation (PNF stretching of the shoulder internal rotators on throwing velocity. Subjects. 27 male throwers (mean age = 25.1 years old, SD = 2.4 with adequate knowledge of demonstrable throwing mechanics. Study Design. Randomized crossover trial with repeated measures. Methods. Subjects warmed up, threw 10 pitches at their maximum velocity, were randomly assigned to 1 of 3 stretching protocols (static, PNF, or no stretch, and then repeated their 10 pitches. Velocities were recorded after each pitch and average and peak velocities were recorded after each session. Results. Data were analyzed using a repeated measures ANOVA. No significant interaction between stretching and throwing velocity was observed. Main effects for time were not statistically significant. Main effects for the stretching groups were statistically significant. Discussion. Results suggest that stretching of the shoulder internal rotators did not significantly affect throwing velocity immediately after stretching. This may be due to the complexity of the throwing task. Conclusions. Stretching may be included in a thrower's warm-up without any effects on throwing velocity. Further research should be performed using a population with more throwing experience and skill.

  2. The Relation Between Stretching Typology and Stretching Duration: The Effects on Range of Motion.

    Science.gov (United States)

    Thomas, Ewan; Bianco, Antonino; Paoli, Antonio; Palma, Antonio

    2018-04-01

    Different stretching strategies and protocols are widely used to improve flexibility or maintain health, acting on the muscle tendon-unit, in order to improve the range of motion (ROM) of the joints. This review aims to evaluate the current body of literature in order to understand the relation between stretching typology and ROM, and secondly to evaluate if a relation exists between stretching volume (either as a single training session, weekly training and weekly frequency) and ROM, after long-term stretching. Twenty-three articles were considered eligible and included in the quantitative synthesis. All stretching typologies showed ROM improvements over a long-term period, however the static protocols showed significant gains (p<0.05) when compared to the ballistic or PNF protocols. Time spent stretching per week seems fundamental to elicit range of movement improvements when stretches are applied for at least or more than 5 min, whereas the time spent stretching within a single session does not seem to have significant effects for ROM gains. Weekly frequency is positively associated to ROM. Evaluated data indicates that performing stretching at least 5 days a week for at least 5 min per week using static stretching may be beneficial to promote ROM improvements. © Georg Thieme Verlag KG Stuttgart · New York.

  3. Short Durations of Static Stretching when Combined with Dynamic Stretching do not Impair Repeated Sprints and Agility.

    Science.gov (United States)

    Wong, Del P; Chaouachi, Anis; Lau, Patrick W C; Behm, David G

    2011-01-01

    This study aimed to compare the effect of different static stretching durations followed by dynamic stretching on repeated sprint ability (RSA) and change of direction (COD). Twenty-five participants performed the RSA and COD tests in a randomized order. After a 5 min aerobic warm up, participants performed one of the three static stretching protocols of 30 s, 60 s or 90 s total duration (3 stretches x 10 s, 20 s or 30 s). Three dynamic stretching exercises of 30 s duration were then performed (90 s total). Sit-and-reach flexibility tests were conducted before the aerobic warm up, after the combined static and dynamic stretching, and post- RSA/COD test. The duration of static stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit-and-reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001). However there were no significant differences in RSA and COD performance between the 3 stretching conditions. The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects. Furthermore, the short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments. Key pointsThe duration of combined static and dynamic stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit and reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001).No significant differences in RSA and COD between the 3 stretching conditions.The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects.The short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments.

  4. Short Durations of Static Stretching when Combined with Dynamic Stretching do not Impair Repeated Sprints and Agility

    Science.gov (United States)

    Wong, Del P.; Chaouachi, Anis; Lau, Patrick W.C.; Behm, David G.

    2011-01-01

    This study aimed to compare the effect of different static stretching durations followed by dynamic stretching on repeated sprint ability (RSA) and change of direction (COD). Twenty-five participants performed the RSA and COD tests in a randomized order. After a 5 min aerobic warm up, participants performed one of the three static stretching protocols of 30 s, 60 s or 90 s total duration (3 stretches x 10 s, 20 s or 30 s). Three dynamic stretching exercises of 30 s duration were then performed (90 s total). Sit-and-reach flexibility tests were conducted before the aerobic warm up, after the combined static and dynamic stretching, and post- RSA/COD test. The duration of static stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit-and-reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001). However there were no significant differences in RSA and COD performance between the 3 stretching conditions. The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects. Furthermore, the short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments. Key points The duration of combined static and dynamic stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit and reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001). No significant differences in RSA and COD between the 3 stretching conditions. The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects. The short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments. PMID:24149890

  5. Comparison electrical stimulation and passive stretching for blood glucose control type 2 diabetes mellitus patients

    Science.gov (United States)

    Arsianti, Rika Wahyuni; Parman, Dewy Haryanti; Lesmana, Hendy

    2018-04-01

    Physical exercise is one of the cornerstones for management and treatment type 2 diabetes mellitus. But not all people are able to perform physical exercise because of their physical limitation condition. The strategy for those people in this study is electrical stimulation and passive stretching. The aim of this study is to find out the effect of electrical stimulation and passive stretching to lowering blood glucose level. 20 subjects is divided into electrical stimulation and passive stretching group. The provision of electrical stimulation on lower extremities muscles for 30 minutes for electrical stimulation group (N=10). And other underwent passive stretching for 30 minutes (N=10). The result shows that blood glucose level is decrease from 192.9 ± 10.7087 mg/dL to 165.3 ± 10.527 mg/dL for electrical stimulation intervention group while for the passive stretching group the blood glucose decrease from 153 ± 12.468 mg/dL to 136.1 ± 12.346 mg/dL. Both electrical stimulation and passive stretching are effective to lowering blood glucose level and can be proposed for those people restricted to perform exercise.

  6. Acute effect of different time periods of passive static stretching on the hamstring flexibility.

    Science.gov (United States)

    Cini, Anelize; de Vasconcelos, Gabriela Souza; Lima, Claudia Silveira

    2017-01-01

    Several factors are associated with the presence of chronic low back pain; one of them is the flexibility of the hamstring muscles that influences the posture of the pelvic spine. Investigate the influence of two different time periods of passive static stretching on the flexibility of the hamstring. Forty-six physiotherapy students were divided into two groups performing stretching exercises: 30 s and 60 s duration. The collections consisted of: (1) pre-test: evaluation of the flexibility of the hip and knee, using a manual goniometer by means of the following tests: Straight Leg Raise Test (SLR), Passive Hip Flexion Test (PHFT) and Modified Knee Extension Test (MKET), (2) intervention: stretching with different runtimes, (3) post-test: reappraisal of flexibility, conducted immediately after the intervention. Significant difference was observed intra groups, group that did stretching exercises lasting 30 seconds (G30) (SLR p = 0.000. PHFT p = 0.003 and MKET p = 0.000) and group that did stretching exercises lasting 60 seconds (G60) (SLR p = 0.000. PHFT p = 0.001 and MKET p = 0.002). Comparing the groups, no significant difference was found (SLR p = 0.307; PHFT p = 0.904; MKET p = 0.132). Thus it can be inferred that 30 seconds are sufficient for increased flexibility of young women. Therefore the time-treatment sessions can be optimized. Only the acute effect of stretching was observed; further investigation of the long-term effect is required.

  7. Randomized Trial of Modified Stretching Exercise Program for Menstrual Low Back Pain.

    Science.gov (United States)

    Chen, Huei-Mein; Hu, Hsou-Mei

    2018-03-01

    This study aimed to examine the effectiveness of a modified stretching exercise program on young women with menstrual low back pain. Overall, 127 young women were randomly assigned to the experimental ( n = 63) and control ( n = 64) groups. The experimental group followed the modified stretching exercise program, whereas the control group performed their usual activities. At 1, 4, 8, and 12 months, the experimental group had significantly lower scores on the visual analog scale for pain (95% confidence interval [CI] = [0.73, 1.96]; p < .05) and the Oswestry Low Back Pain Disability Questionnaire than the control group (95% CI = [0.68, 2.03]; p < .001). At 12 months, the experimental group showed significantly higher exercise self-efficacy than the control group (95% CI = [-6.87, 0.62]; p = .003). These findings can be used to enhance self-care capabilities by using the modified stretching exercise program for young women with menstrual low back pain.

  8. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS (DPG)

    CERN Document Server

    D. Acosta

    Run coordination and DPG The activities of the DPGs in the last six months have included the completion of publications (and many internal notes) on the data collected during CRAFT08 exercise, continuation of these studies with CRAFT09 data, and finally the first workflows and prompt feedback on 2009 LHC beam data. The level of readiness of the DPG prompt feedback groups is quite high, as first results from the early November “beam splash” data were shown to CMS within 24 hours of the first LHC beam. Moreover, results from the first collisions at 900 GeV were presented publicly three days afterward on November 26th. The CRAFT09 cosmic data taking period provided an opportunity to commission the calibration and alignment workflows on large data samples using the same software release series intended for the first LHC data, and to demonstrate routine operation of alignment and calibration workflows under production conditions. Significantly, the "prompt calibration loop" wa...

  9. Stretch due to Penile Prosthesis Reservoir Migration

    Directory of Open Access Journals (Sweden)

    E. Baten

    2016-03-01

    Full Text Available A 43-year old patient presented to the emergency department with stretch, due to impossible deflation of the penile prosthesis, 4 years after successful implant. A CT-scan showed migration of the reservoir to the left rectus abdominis muscle. Refilling of the reservoir was inhibited by muscular compression, causing stretch. Removal and replacement of the reservoir was performed, after which the prosthesis was well-functioning again. Migration of the penile prosthesis reservoir is extremely rare but can cause several complications, such as stretch.

  10. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS (DPG)

    CERN Multimedia

    D. Acosta

    Point 5 commissioning activities Since the last CMS week there has been little global commissioning activities: the first mid week global run aiming to assess the status of the hardware and DAQ software after the winter maintenance and developments has taken place two weeks ago involving all subdetectors but tracker and pixel whose hardware is still being actively worked on. The local commissioning restarted once the cooling became available again the third week of January. Below are detailed the main activities which have taken place so far. DAQ The activity of the central DAQ group during pause of global runs was focused on various items. The commissioning of the 900 new PCs which will be used to run the HLT processes has been almost completed. It is planned to use these PCs in the first global run at the start of March. In addition the location of various server PCs which host essential functionalities to get the private ".cms" network going, has been re-organized to allow to implemen...

  11. The effects of two methods of reflexology and stretching exercises on the severity of restless leg syndrome among hemodialysis patients.

    Science.gov (United States)

    Shahgholian, Nahid; Jazi, Shahrzad Khojandi; Karimian, Jahangir; Valiani, Mahboubeh

    2016-01-01

    Restless leg syndrome prevalence is high among the patients undergoing hemodialysis. Due to several side effects of medicational treatments, the patients prefer non-medicational methods. Therefore, the present study aimed to investigate the effects of two methods of reflexology and stretching exercises on the severity of restless leg syndrome among patients undergoing hemodialysis. This study is a randomized clinical trial that was done on 90 qualified patients undergoing hemodialysis in selected hospitals of Isfahan, who were diagnosed with restless leg syndrome through standard restless leg syndrome questionnaire. They were randomly assigned by random number table to three groups: Reflexology, stretching exercises, and control groups through random allocation. Foot reflexology and stretching exercises were conducted three times a week for 30-40 min within straight 4 weeks. Data analysis was performed by SPSS version 18 using descriptive and inferential statistical analyses [one-way analysis of variance (ANOVA), paired t-test, and least significant difference (LSD) post hoc test]. There was a significant difference in the mean scores of restless leg syndrome severity between reflexology and stretching exercises groups, compared to control (P reflexology and stretching exercises groups compared to the control group (P reflexology massage and stretching exercises groups. Our obtained results showed that reflexology and stretching exercises can reduce the severity of restless leg syndrome. These two methods of treatment are recommended to the patients.

  12. Transactive memory in organizational groups: the effects of content, consensus, specialization, and accuracy on group performance.

    Science.gov (United States)

    Austin, John R

    2003-10-01

    Previous research on transactive memory has found a positive relationship between transactive memory system development and group performance in single project laboratory and ad hoc groups. Closely related research on shared mental models and expertise recognition supports these findings. In this study, the author examined the relationship between transactive memory systems and performance in mature, continuing groups. A group's transactive memory system, measured as a combination of knowledge stock, knowledge specialization, transactive memory consensus, and transactive memory accuracy, is positively related to group goal performance, external group evaluations, and internal group evaluations. The positive relationship with group performance was found to hold for both task and external relationship transactive memory systems.

  13. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS (DPG)

    CERN Multimedia

    2010-01-01

    The period since the last CMS week has witnessed the start of the LHC as a 'physics' machine. The excitement of the first collisions at 7 TeV on March 30 will be remembered for a long time! The preparation for the event was meticulous. The LHC was pushed to deliver non-colliding stable beams prior to the real collisions, which allowed CMS teams to use the few beam gas interactions within the length of the pixel detector to verify that the beams would indeed collide once both beams were circulating and the separation bump was collapsed. In passing, this exercise allowed us to catch some last minute features of the system, which could have affected our performance on the day! The first collisions were detected practically simultaneously around the ring. Within tens of minutes not only event displays, but also some physics distributions were delivered to the audience of the press conference. A plan of work had been carefully defined on how to use the first collisions following the first hour of excitement. I...

  14. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS (DPG)

    CERN Multimedia

    L. Malgeri

    2010-01-01

    The last six months have been very intense for run coordination as this period corresponds to the time most of the LHC luminosity has been delivered. The pace imposed by the LHC has marked the operation of the CMS detector and data logging: the luminosity has on average doubled every 10 days. Sometimes, this has strained our activities: the trigger teams, both Level-1 and HLT, have been in the trenches to cope with the spectacular LHC performance in order to keep the thresholds as low as possible for e/γs and jet triggers in order to make the physics community profit as much as possible from the data delivered. The constant effort to stay at the edge of our possibilities (essentially stay at or below 70 kHz for the first level trigger rates and below 600 Hz logging rates) has paid off in the end. Examples are the beautiful di-muon and di-electron invariant mass distributions where we are able, for instance, to detect low mass resonance like the h in the di-muon decay channel which has branching rat...

  15. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS (DPG)

    CERN Multimedia

    L. Malgeri

    2011-01-01

    As the technical interventions were finishing up and services restored at P5 we started central operations again in 2011. We started operations with a reduced shift crew, Shift leader and DCS shifter, on 24th January. We had a first mid-week global run on 2nd and 3rd February followed by cosmic data-taking between 10th and 20th February. Due to delays with cooling for the strip tracker the useful cosmic data-taking with the strip tracker was reduced to about four days. On 20th February, the LHC started beam commissioning, and cosmic data-taking with the full CMS detector was stopped. The machine availability has been much higher during the 2011 beam commissioning than during the comparable time period in 2010. This has given us few opportunities to turn on the tracker for further cosmic data-taking. Many changes and upgrades were performed during the winter shutdown. Among them was an upgrade to running the central DAQ on 64 bit. All of these upgrades have now b...

  16. Effects of Combining Running and Practical Duration Stretching on Proprioceptive Skills of National Sprinters.

    Science.gov (United States)

    Romero-Franco, Natalia; Párraga-Montilla, Juan Antonio; Molina-Flores, Enrique M; Jiménez-Reyes, Pedro

    2018-06-01

    Romero-Franco, N, Párraga-Montilla, JA, Molina-Flores, EM, and Jiménez-Reyes, P. Effects of combining running and practical duration stretching on proprioceptive skills of national sprinters. J Strength Cond Res XX(X): 000-000, 2018-Practical duration stretching after aerobic activities is a recommended component of the first part of warm-up because of its effects on performance. However, its effects on proprioceptive skills are unknown. This study aimed to analyze the effects of running and practical duration static stretching (SS) and dynamic stretching (DS) on postural balance and the joint position sense (JPS) of national sprinters. Thirty-two national sprinters were randomly classified into a SS group (n = 11), DS group (n = 11), or control group (n = 10). Static stretching performed 5 minutes of running and short-duration (20 seconds) static stretches; DS performed 5 minutes of running and short-duration dynamic (20 seconds) stretches; and the control group performed 5 minutes of running. Before and after the intervention, unipedal static postural balance and knee JPS were evaluated. Static stretching exhibited a more centralized center of pressure in the medial-lateral plane for unipedal static postural balance in right-leg support after stretching (p = 0.005, d = 1.24), whereas DS showed values further from the center after stretching for the same unipedal support compared with baseline (p = 0.042, d = 0.49), and the control group remained stable (p > 0.05). Joint position sense did not show significant differences in any group (p > 0.05). In conclusion, combining running and practical duration SS may be beneficial for right-leg postural stabilization, whereas DS may be partly and slightly deleterious. Both SS and DS combined with running and running alone have neutral effects on knee JPS. Sports professionals should consider running and practical duration SS as part of the warm-up of sprinters to partly improve unipedal static postural balance.

  17. The acute effects of stretching with vibration on dynamic flexibility in young female gymnasts.

    Science.gov (United States)

    Johnson, Aaron W; Warcup, Caisa N; Seeley, Matthew K; Eggett, Dennis; Feland, Jeffery B

    2018-01-10

    While stretching with vibration has been shown to improve static flexibility; the effect of stretching with vibration on dynamic flexibility is not well known. The purpose of this study was to examine the effectiveness of stretching with vibration on acute dynamic flexibility and jump height in novice and advanced competitive female gymnasts during a split jump. Female gymnast (n=27, age: 11.5 ± 1.7 years, Junior Olympic levels 5-10) participated in this cross-over study. Dynamic flexibility during gymnastic split jumps were video recorded and analyzed with Dartfish software. All participants completed both randomized stretching protocols with either the vibration platform turned on (VIB) (frequency of 30 Hz and 2 mm amplitude) or off (NoVIB) separated by 48 h. Participants performed 4 sets of three stretches on the vibration platform. Each stretch was held for 30 s with 5 s rest for a total of 7 min of stretch. Split jump flexibility decreased significantly from pre to post measurement in both VIB (-5.8°±5.9°) (p<0.001) and NoVIB (-2.6°±6.1°) (p=0.041) conditions (adjusted for gymnast level). This effect was greatest in lower skill level gymnasts (p=0.003), while the highest skill level gymnasts showed no significant decrease in the split jump (p=0.105). Jump height was not significantly different between conditions (p=0.892) or within groups (p=0.880). An acute session of static stretching with or without vibration immediately before performance does not alter jump height. Stretching with vibration immediately prior to gymnastics competition decreases split jump flexibility in lower level gymnasts more than upper level gymnasts.

  18. Acute effects of static stretching on peak and end-range hamstring-to-quadriceps functional ratios

    Science.gov (United States)

    Sekir, Ufuk; Arabaci, Ramiz; Akova, Bedrettin

    2015-01-01

    AIM: To evaluate if static stretching influences peak and end-range functional hamstring-to-quadriceps (H/Q) strength ratios in elite women athletes. METHODS: Eleven healthy female athletes in an elite competitive level participated to the study. All the participants fulfilled the static stretching or non-stretching (control) intervention protocol in a randomized design on different days. Two static unassisted stretching exercises, one in standing and one in sitting position, were used to stretch both the hamstring and quadriceps muscles during these protocols. The total time for the static stretching was 6 ± 1 min. The isokinetic peak torque measurements for the hamstring and quadriceps muscles in eccentric and concentric modes and the calculations for the functional H/Q strength ratios at angular velocities of 60°/s and 180°/s were made before (pre) and after (post) the control or stretching intervention. The strength measurements and functional strength ratio calculations were based during the entire- and end-range of knee extension. RESULTS: The pre-test scores for quadriceps and hamstring peak torque and end range values were not significantly different between the groups (P > 0.05). Subsequently, although the control group did not exhibit significant changes in quadriceps and hamstring muscle strength (P > 0.05), static stretching decreased eccentric and concentric quadriceps muscle strength at both the 60°/s and 180°/s test speeds (P hamstring muscle strength at both the 60°/s and 180°/s test speeds (P 0.05). Furthermore, the functional H/Q strength ratios exhibited no significant alterations during the entire and end ranges of knee extension both in the static stretching or the control intervention (P > 0.05). CONCLUSION: According to our results, static stretching routine does not influence functional H/Q ratio. Athletes can confidently perform static stretching during their warm-up routines. PMID:26495249

  19. SHORT DURATIONS OF STATIC STRETCHING WHEN COMBINED WITH DYNAMIC STRETCHING DO NOT IMPAIR REPEATED SPRINTS AND AGILITY

    Directory of Open Access Journals (Sweden)

    Del P. Wong

    2011-06-01

    Full Text Available This study aimed to compare the effect of different static stretching durations followed by dynamic stretching on repeated sprint ability (RSA and change of direction (COD. Twenty-five participants performed the RSA and COD tests in a randomized order. After a 5 min aerobic warm up, participants performed one of the three static stretching protocols of 30 s, 60 s or 90 s total duration (3 stretches x 10 s, 20 s or 30 s. Three dynamic stretching exercises of 30 s duration were then performed (90 s total. Sit-and-reach flexibility tests were conducted before the aerobic warm up, after the combined static and dynamic stretching, and post- RSA/COD test. The duration of static stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit-and-reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p < 0.001. However there were no significant differences in RSA and COD performance between the 3 stretching conditions. The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects. Furthermore, the short duration (< 90 s static stretching may not have provided sufficient stimulus to elicit performance impairments

  20. Constellation Stretch Goals: Review of Industry Inputs

    Science.gov (United States)

    Lang, John

    2006-01-01

    Many good ideas received based on industry experience: a) Shuttle operations; b) Commercial aircraft production; c) NASA's historical way of doing business; d) Military and commercial programs. Aerospace performed preliminary analysis: a) Potential savings; b) Cost of implementation; c) Performance or other impact/penalties; d) Roadblocks; e) Unintended consequences; f) Bottom line. Significant work ahead for a "Stretch Goal"to become a good, documented requirement: 1) As a group, the relative "value" of goals are uneven; 2) Focused analysis on each goal is required: a) Need to ensure that a new requirement produces the desired consequence; b) It is not certain that some goals will not create problems elsewhere. 3) Individual implementation path needs to be studied: a) Best place to insert requirement (what level, which document); b) Appropriate wording for the requirement. Many goals reflect "best practices" based on lessons learned and may have value beyond near-term CxP requirements process.

  1. The Performance of Step-Wise Group Screening Designs

    Directory of Open Access Journals (Sweden)

    M.M. Manene

    2005-06-01

    Full Text Available In this paper we evaluate the performance of step-wise group screening designs in which group-factors contain an equal number of factors in the initial step.  A usual assumption in group screening designs is that the directions of possible effects are known a-priori. In practice, however, this assumption is unreasonable. We shall examine step-wise group screening designs without errors in observations when this assumption is relaxed. We shall consider cancellations of effects within group-factors. The performance of step-wise group-screening designs shall then be compared with the performance of multistage group screening designs.

  2. Effects of hamstring stretch with pelvic control on pain and work ability in standing workers.

    Science.gov (United States)

    Han, Hyun-Il; Choi, Ho-Suk; Shin, Won-Seob

    2016-11-21

    Hamstring tightness induces posterior pelvic tilt and decreased lumbar lordosis, which can result in low back painOBJECTIVE: We investigated effects of hamstring stretch with pelvic control on pain and work ability in standing workers. One hundred adult volunteers from a standing workers were randomly assigned to pelvic control hamstring stretching (PCHS) (n = 34), general hamstring stretching (GHS) (n = 34), control (n = 32) groups. The control group was performed self-home exercise. All interventions were conducted 3 days per week for 6 weeks, and included in the hamstring stretching and lumbopelvic muscle strengthening. Outcomes were evaluated through the visual analog scale (VAS), straight leg raise test (SLR), sit and reach test (SRT), Oswestry disability index (ODI), and work ability index (WAI). Significant difference in VAS, SLR, SRT, ODI, and WAI were found in the PCHS and GHS groups. The control group was a significant difference only in ODI. The PCHS group showed a greater difference than the GHS group and control group in VAS, SLR, SRT, and ODI. The pelvic control hamstring stretch exercise would be more helpful in back pain reduction and improvement of work ability in an industrial setting.

  3. Muscle oxygenation and fascicle length during passive muscle stretching in ballet-trained subjects.

    Science.gov (United States)

    Otsuki, A; Fujita, E; Ikegawa, S; Kuno-Mizumura, M

    2011-07-01

    Muscle stretching transiently decreases muscle-blood flow corresponding to a muscle extension. It may disturb a balance between muscular oxygen demand and oxygen supply to muscles and reduce muscle oxygenation. However, muscle-stretching training may improve blood circulatory condition, resulting in the maintained muscle oxygenation during muscle stretching. The aim of this study was to investigate changes in muscle-blood volume (tHb) and tissue oxygenation index (TOI) during muscle stretching determined by using near-infrared spectroscopy (NIRS) in ballet-trained (BT) and untrained (C) subjects. 11 BT women who regularly perform muscle stretching and 11 C women participated in this study. Fascicle lengths, tHb and TOI in the tibialis anterior muscle were measured during passive plantar flexion from ankle joint angles of 120° (baseline) to 140°, 160°, the maximal comfortable position without pain (CP), and the maximal position (MP). At 160°, the % fascicle-length change from baseline was significantly lower in the BT than the C group, however, for the changes in tHb and TOI the significant interaction effect between the 2 groups was not detected. On the other hand, although the increases in the fascicle length from baseline to CP and MP were greater in BT than C, the tHb and TOI reductions were comparable between groups. We concluded that it appears that BT can extend their muscles without excessive reduction in muscle-blood volume and muscle oxygenation at relatively same but absolutely greater muscle-stretching levels than C. The attenuation in these indices during high-level muscle stretching may be associated with the repetitive muscle stretching of long-term ballet training. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Stretching & Flexibility: An Interactive Encyclopedia of Stretching. [CD-ROM].

    Science.gov (United States)

    2002

    This CD-ROM offers 140 different stretches in full-motion video sequences. It focuses on the proper techniques for overall physical fitness, injury prevention and rehabilitation, and 23 different sports (e.g., golf, running, soccer, skiing, climbing, football, and baseball). Topics include stretching for sports; stretching awareness and education…

  5. Passive Stretch Versus Active Stretch on Intervertebral Movement in Non - Specific Neck Pain

    International Nuclear Information System (INIS)

    Abd El - Aziz, A.H.; Amin, D.I.; Moustafa, I.

    2016-01-01

    Neck pain is one of the most common and painful musculoskeletal conditions. Point prevalence ranges from 6% to 22% and up to 38% of the elderly population, while lifetime prevalence ranges from 14,2% to 71%. Up till now no randomized study showed the effect between controversy of active and passive stretch on intervertebral movement. The purpose: the current study was to investigate the effect of the passive and active stretch on intervertebral movement in non - specific neck pain. Material and methods: Forty five subjects from both sexes with age range between 18 and 30 years and assigned in three groups, group I (15) received active stretch, ultrasound and TENS. Group II (15) received passive stretch, ultrasound and TENS. Group III (15) received ultrasound and TENS. The radiological assessment was used to measure rotational and translational movement of intervertebral movement before and after treatment. Results: MANOVA test was used for radiological assessment before and after treatment there was significant increase in intervertebral movement in group I as p value =0.0001. Conclusion: active stretch had a effect in increasing the intervertebral movement compared to the passive stretch

  6. Stretching the Border

    DEFF Research Database (Denmark)

    Horstmann, Alexander

    2014-01-01

    In this paper, I hope to add a complementary perspective to James Scott’s recent work on avoidance strategies of subaltern mountain people by focusing on what I call the refugee public. The educated Karen elite uses the space of exile in the Thai borderland to reconstitute resources and to re-ent......-based organizations succeed to stretch the border by establishing a firm presence that is supported by the international humanitarian economy in the refugee camps in Northwestern Thailand....

  7. Introduction of the UNIX International Performance Management Work Group

    Science.gov (United States)

    Newman, Henry

    1993-01-01

    In this paper we presented the planned direction of the UNIX International Performance Management Work Group. This group consists of concerned system developers and users who have organized to synthesize recommendations for standard UNIX performance management subsystem interfaces and architectures. The purpose of these recommendations is to provide a core set of performance management functions and these functions can be used to build tools by hardware system developers, vertical application software developers, and performance application software developers.

  8. EFFICACY OF MODIFIED PROPRIOCEPTIVE NEUROMUSCULAR FACILITATION STRETCHING WITH CRYOTHERAPY OVER MANUAL PASSIVE STRETCHING WITH CRYOTHERAPY ON HAMSTRING FLEXIBILITY

    Directory of Open Access Journals (Sweden)

    Shamik Bhattacharjee

    2016-04-01

    Full Text Available Background: Healthy individuals, to ease and accomplish their activities of daily living they need flexible body without any tightness in the muscles, particularly those used for a definite function. Cooling soft tissues in a lengthened position after stretching has been shown to promote more lasting increases in soft tissue length and minimize post stretch muscle soreness. There are less documented studies which compared modified proprioceptive neuromuscular facilitation (PNF stretch over passive manual stretch with cold application commonly after the interventions. Methods: Thirty high school going healthy students were divided into two groups- Group I received Passive Manual stretching (n=15 and Group II received modified PNF stretching (n=15 and both groups received cold application after the interventions for 10 minutes commonly for 5 days. ROM was taken on day 1, day 5 and day 7. Results: After day 7, Group II with Modified PNF stretching along with cold application showed a significant increase in range of motion tested with active knee extension test (AKET. Conclusion: Modified PNF stretching is considered to be the effective intervention in increasing and maintaining ROM in AKET over passive manual stretching with cold applications commonly after the interventions.

  9. EFFECTIVENESS OF PNF STRETCHING AND CYCLIC STRETCHING OF CALF TIGHTNESS ON COLLEGE GOING GIRLS

    Directory of Open Access Journals (Sweden)

    Ashlesha Sirari

    2015-06-01

    Full Text Available Background: Flexibility helps with injury prevention, the reduction of soreness following a workout, and a general sense of well-being. There are different stretching techniques and protocols for improvements in calf extensibility and flexibility. The purpose of the study was to investigate the effectiveness of two techniques i.e. CYCLIC and PNF stretching which improves calf flexibility. This study was done to find the effectiveness of calf Cyclic and PNF stretching technique to improve calf flexibility. Methods: 30 subjects with age group 21-22 years were randomly allocated to 2 groups equally. Group 1(n=15 were given CYCLIC and group 2(n=15 were given PNF stretching technique. Plantar flexion was used to measure the calf tightness which was done before and after the treatment. Treatment was given for 7 days and on the 7th day the calf tightness was again measured. Results: The mean difference of the CYCLIC is 4.6 and mean difference of PNF is 4.7 which indicate that CYCLIC and PNF both are effective to improve calf flexibility but PNF is more effective than CYCLIC to improve calf flexibility. Conclusion: The neurophysiological basis of PNF, stating that the excitatory efficient of the neuromuscular spindle or the inhibitory afferent of the Golgi tendon organ (GTO or both are responsible for the effects. During PNF stretch and isometric contraction of stretched agonists for extended period may cause activation of its neuromuscular spindle. The increase in tension created during the isometric contraction of the pre – lengthened agonist contracts concentrically. Both the fascia & the spindle of the agonist adjust to the nearly lengthened position. These impulses travel via causing post synaptic inhibition of the motor neuron to agonist increasing the tension from the GTO. These impulses can override the impulses coming from the neuromuscular spindles arousing the muscle to reflexly resist to the change in length, thus helping in lengthening

  10. A FINANCIAL PERFORMANCE COMPARISON OF GROUP AND NON-GROUP FIRMS IN TEXTILE SECTOR OF PAKISTAN

    Directory of Open Access Journals (Sweden)

    Ishtiaq AHMAD

    2016-12-01

    Full Text Available Pakistan is a developing economy and business groups are key players of the Pakistan’s economy. Previous research evidence shows that in the emerging economies group affiliation creates value for the firms. This study is intended to empirically investigate to know that whether group affiliated (GA firms perform financially better than non-group affiliated firms or not? GA firms in emerging economies can have better financial performance by sharing tangible and intangible resources at group level. The financial ratio is used to compare performance of affiliated and non-group affiliated firms by using the data of 70 textile firms listed at Karachi Stock Exchange(now Pakistan Stock Exchange covering a period from 2008 to 2012. Based on mean values of return on assets (ROA, results of the study show that GA firms have higher financial performance than non-group affiliated firms in each year and over all five years.

  11. Friends With Performance Benefits: A Meta-Analysis on the Relationship Between Friendship and Group Performance.

    Science.gov (United States)

    Chung, Seunghoo; Lount, Robert B; Park, Hee Man; Park, Ernest S

    2018-01-01

    The current article examines if, and under which conditions, there exists a positive relationship between working with friends and group performance. To do so, using data from 1,016 groups obtained from 26 studies, we meta-analyzed comparisons of the performance of friendship groups versus acquaintance groups. Results show that friendship has a significant positive effect on group task performance (Cohen's d = 0.31). Furthermore, this relationship was moderated by group size (i.e., the positive effect of friendship on performance increased with group size) and task focus (i.e., friendship groups performed better than acquaintance groups on tasks requiring a high quantity of output, whereas there was no performance benefit on tasks requiring a single or high-quality output). These results help to reconcile mixed findings and illustrate when friendship groups are more likely to perform better than acquaintance groups.

  12. Letting the Drama into Group Work: Using Conflict Constructively in Performing Arts Group Practice

    Science.gov (United States)

    Crossley, Tracy

    2006-01-01

    The article examines conflict avoidance in performing arts group work and issues arising in relation to teaching and learning. In group theory, conflict is addressed largely in terms of its detrimental effects on group work, and its constructive potential is often marginalized. Similarly, undergraduate students usually interpret "effective…

  13. Working group 4B - human intrusion: Design/performance requirements

    International Nuclear Information System (INIS)

    Channell, J.

    1993-01-01

    There is no summary of the progress made by working group 4B (Human Intrusion: Design/performance Requirements) during the Electric Power Research Institute's EPRI Workshop on the technical basis of EPA HLW Disposal Criteria, March 1993. This group was to discuss the waste disposal standard, 40 CFR Part 191, in terms of the design and performance requirements of human intrusion. Instead, because there were so few members, they combined with working group 4A and studied the three-tier approach to evaluating postclosure performance

  14. A task dependent change in the medium latency component of the soleus stretch reflex

    DEFF Research Database (Denmark)

    Grey, Michael James; Larsen, Birgit; Sinkjær, Thomas

    2002-01-01

    In comparison to the H-reflex, the task dependency of the human stretch reflex during locomotive and postural tasks has not received a great deal of attention in the literature. The few studies on reflex task dependency that have been performed to date have concentrated on either the group Ia...

  15. A COMPARATIVE STUDY ON EFFECTIVENESS OF STATIC STRETCH AND HOLD RELAX TECHNIQUES OVER HAMSTRING FLEXIBILITY

    Directory of Open Access Journals (Sweden)

    N. Vamsidhar

    2014-12-01

    Full Text Available Background: Flexibility is important in prevention of injury, muscular and postural imbalance more over the Hamstring flexibility has a lion share in sports performances and preventing DOMS. Stretching procedures increases the ROM by embarking on biomechanics and Neurologic and molecular mechanics. Hamstrings, the two joint muscle plays a crucial role in two joints integrity and also spine as they are in closed kinematic chain. The hamstring muscles represent the primary flexors of Knee. Hamstrings tightness results in Limits Knee extension when hip is flexed, Posterior Pelvic tilt, and flatten the lumbar spine. Methods: The subjects selected randomly and divided into two groups (Experimental group and control group.30 samples in One group applied with Static Stretch once a day for 3 repetitions 5 days a week for six weeks and 30 samples in other group applied with Hold relax technique once a day for 4 repetitions 5 days a week for six weeks. The knee joint range of motion was measured at the end of every week with Universal goniometer. Results: By comparing the means of Group – I, given Static Stretch and Group – II, given Hold relax Technique for six weeks implied that there is improvement of flexibility in Group – II and the ‘P’ value < 0.01 shows the difference is highly significant. Conclusion: This study concludes that the hold relax Technique method has proved to be better technique then the static stretch for improving hamstring flexibility.

  16. Influence of ABO blood group on sports performance.

    Science.gov (United States)

    Lippi, Giuseppe; Gandini, Giorgio; Salvagno, Gian Luca; Skafidas, Spyros; Festa, Luca; Danese, Elisa; Montagnana, Martina; Sanchis-Gomar, Fabian; Tarperi, Cantor; Schena, Federico

    2017-06-01

    Despite being a recessive trait, the O blood group is the most frequent worldwide among the ABO blood types. Since running performance has been recognized as a major driver of evolutionary advantage in humans, we planned a study to investigate whether the ABO blood group may have an influence on endurance running performance in middle-aged recreational athletes. The study population consisted of 52 recreational, middle-aged, Caucasian athletes (mean age: 49±13 years, body mass index, 23.4±2.3 kg/m 2 ), regularly engaged in endurance activity. The athletes participated to a scientific event called "Run for Science" (R4S), entailing the completion of a 21.1 km (half-marathon) run under competing conditions. The ABO blood type status of the participants was provided by the local Service of Transfusion Medicine. In univariate analysis, running performance was significantly associated with age and weekly training, but not with body mass index. In multiple linear regression analysis, age and weekly training remained significantly associated with running performance. The ABO blood group status was also found to be independently associated with running time, with O blood type athletes performing better than those with non-O blood groups. Overall, age, weekly training and O blood group type explained 62.2% of the total variance of running performance (age, 41.6%; training regimen, 10.5%; ABO blood group, 10.1%). The results of our study show that recreational athletes with O blood group have better endurance performance compared to those with non-O blood group types. This finding may provide additional support to the putative evolutionary advantages of carrying the O blood group.

  17. Business group performance, context, and strategy: A meta-analysis

    NARCIS (Netherlands)

    M. Carney (Michael); E.R. Gedajlovic (Eric); P.P.M.A.R. Heugens (Pursey); M. van Essen (Marc); J. van Oosterhout (Hans)

    2010-01-01

    textabstractResearch on business groups ?legally independent firms tied together in a variety of formal and informal ways ?is accelerating, but four questions still lack a definitive answer: Does business group membership enhance or diminish firm performance? Are members comparatively better off in

  18. Immediate effects of different types of stretching exercises on badminton jump smash.

    Science.gov (United States)

    Jang, Hwi S; Kim, Daeho; Park, Jihong

    2018-01-01

    Since different types of stretching exercises may alter athletic performance, we compared the effects of three types of stretching exercises on badminton jump smash. Sixteen male collegiate badminton players performed one of three different stretching exercises in a counterbalanced order on different days. Static stretching had seven typical stretches, while dynamic stretching involved nine dynamic movements, and resistance dynamic stretching was performed with weighted vests and dumbbells. Before and after each stretching exercise, subjects performed 20 trials of jump smashes. Dependent measurements were the jump heights during jump smashes, velocities of jump-smashed shuttlecocks, and drop point of jump-smashed shuttlecocks. To test the effects of each stretching exercise, we performed mixed model ANOVAs and calculated between-time effect sizes (ES). Each stretching exercise improved the jump heights during jump smashes (type main effect: F(2,75)=1.19, P=0.31; static stretching: 22.1%, Pjump-smashed shuttlecocks (type main effect: F(2,75)=2.18, P=0.12; static stretching: 5.7%, P=0.61, ES=0.39; dynamic stretching: 3.4%, P=0.94, ES=0.28; resistance dynamic stretching: 6%, P=0.50, ES=0.66). However, there were no differences among the stretching exercises for any measurement. The drop point of jump-smashed shuttlecocks did not change (interaction: F(2,75)=0.88, P=0.42). All stretching exercises improved badminton jump smash performance, but we could not determine the best protocol. Since badminton requires high-speed movement and explosive force, we suggest performing dynamic stretching or resistance dynamic stretching.

  19. EFFECTIVENESS OF PNF STRETCHING VERSUS STATIC STRETCHING ON PAIN AND HAMSTRING FLEXIBILITY FOLLOWING MOIST HEAT IN INDIVIDUALS WITH KNEE OSTEOARTHRITIS

    Directory of Open Access Journals (Sweden)

    Meena .V

    2016-10-01

    Full Text Available Background: Osteoarthritis (OA is a degenerative joint disease and one of the major public health problem that causesfunctional impairment and reduced quality of life. To compare the effectiveness of PNF Hold relax stretching versus Static stretching on pain and flexibility of hamstring following moist heat in individuals with knee osteoarthritis. Hamstring tightness is the major problem in knee osteoarthritis individuals. Therefore the need of study is comparing the effectiveness of PNF Hold relax stretching versus static stretching on pain and flexibility of hamstrings following moist heat in knee osteoarthritis participants. Determining the effects of PNF Hold relax stretching versus Static stretching along with moist heat on pain and hamstring flexibility by VAS and Active knee extension range of motion in knee osteoarthritis individuals. Methods: 30 subjects with symptoms of knee osteoarthritis were randomly distributed into 2 groups 15 in each group. PNF Hold relax stretching along with moist heat is compared to Static stretching along with moist heat. Pain was measured by Visual Analogue Scale (VAS and hamstring flexibility by Active knee Extension Range of Motion (AKEROM by universal goniometer. Measurements are taken pre and post intervention. Results: The results indicated PNF Hold relax stretching along with moist heat showed a statistically significant improvement in pain (p<0.05 and improvement in hamstring flexibility (p<0.05 when compared to Static stretching along with moist heat. Conclusion: Subjects with PNF Hold relax stretching along with moist heat showed significant improvement in pain reduction and improving hamstring flexibility than Static stretching along with moist heat.

  20. When does power disparity help or hurt group performance?

    Science.gov (United States)

    Tarakci, Murat; Greer, Lindred L; Groenen, Patrick J F

    2016-03-01

    Power differences are ubiquitous in social settings. However, the question of whether groups with higher or lower power disparity achieve better performance has thus far received conflicting answers. To address this issue, we identify 3 underlying assumptions in the literature that may have led to these divergent findings, including a myopic focus on static hierarchies, an assumption that those at the top of hierarchies are competent at group tasks, and an assumption that equality is not possible. We employ a multimethod set of studies to examine these assumptions and to understand when power disparity will help or harm group performance. First, our agent-based simulation analyses show that by unpacking these common implicit assumptions in power research, we can explain earlier disparate findings--power disparity benefits group performance when it is dynamically aligned with the power holder's task competence, and harms group performance when held constant and/or is not aligned with task competence. Second, our empirical findings in both a field study of fraud investigation groups and a multiround laboratory study corroborate the simulation results. We thereby contribute to research on power by highlighting a dynamic understanding of power in groups and explaining how current implicit assumptions may lead to opposing findings. (c) 2016 APA, all rights reserved).

  1. Acute Effects of Static vs. Ballistic Stretching on Strength and Muscular Fatigue Between Ballet Dancers and Resistance-Trained Women.

    Science.gov (United States)

    Lima, Camila D; Brown, Lee E; Wong, Megan A; Leyva, Whitney D; Pinto, Ronei S; Cadore, Eduardo L; Ruas, Cassio V

    2016-11-01

    Lima, CD, Brown, LE, Wong, MA, Leyva, WD, Pinto, RS, Cadore, EL, and Ruas, CV. Acute effects of static vs. ballistic stretching on strength and muscular fatigue between ballet dancers and resistance-trained women. J Strength Cond Res 30(11): 3220-3227, 2016-Stretching is used to increase joint range of motion, but the acute effects can decrease muscle strength. However, this may depend on the population or mode of stretching. The purpose of this study was to compare the acute effects of static vs. ballistic stretching on strength and muscular fatigue between ballet dancers and resistance-trained women. Fifteen resistance-trained women (age 23.8 ± 1.80 years, mass 67.47 ± 7.77 kg, height 168.30 ± 5.53 cm) and 12 ballet dancers (age 22.8 ± 3.04 years, mass 58.67 ± 5.65 kg, height 168.00 ± 7.69 cm) performed 5 days of testing. The first day was control (no stretching), whereas the other 4 days were static or ballistic stretching in a counterbalanced order. Range of motion, strength, and fatigue tests were also performed. Both groups demonstrated a significant decrease in hamstrings strength after static (102.71 ± 2.67 N·m) and ballistic stretching (99.49 ± 2.61 N·m) compared with control (113.059 ± 3.25 N·m), with no changes in quadriceps strength. For fatigue, only ballet dancers demonstrated a decrease from control (71.79 ± 4.88%) to ballistic (65.65 ± 8.19%), but no difference with static (65.01 ± 12.29%). These findings suggest that stretching decreases hamstrings strength similarly in ballet dancers and resistance-trained women, with no differences between modes of stretching. However, ballistic stretching only decreased muscular fatigue in ballet dancers, but not in resistance-trained women. Therefore, no stretching should be performed before strength performance. However, ballistic stretching may decrease acute muscular fatigue in ballet dancers.

  2. Correlation between structure and conductivity in stretched Nafion

    Science.gov (United States)

    Allahyarov, Elshad; Taylor, Philip

    2008-03-01

    We have used coarse-grained simulation methods to investigate the effect of stretching-induced structure orientation on the proton conductivity of Nafion-like polyelectrolyte membranes. Recent experimental data on the morphology of ionomers describe Nafion as an aggregation of polymeric backbone chains forming elongated objects embedded in a continuous ionic medium. Uniaxial stretching of a recast Nafion film causes a preferential orientation of these objects in the direction of stretching. Our simulations of humid Nafion show that this has a strong effect on the proton conductivity, which is enhanced along the stretching direction, while the conductivity perpendicular to the stretched polymer backbone is strongly reduced. Stretching also causes the perfluorinated side chains to orient perpendicular to the stretching axis. The sulphonate multiplets shrink in diameter as the stretching is increased and show a spatially periodic ordering in their distribution. This in turn affects the distribution of contained water at low water contents. The water forms a continuous network with narrow bridges between small water clusters absorbed in head-group multiplets. We find the morphological changes in the stretched Nafion to be retained upon removal of the uniaxial stress.

  3. Performance and consistency of indicator groups in two biodiversity hotspots.

    Directory of Open Access Journals (Sweden)

    Joaquim Trindade-Filho

    Full Text Available In a world limited by data availability and limited funds for conservation, scientists and practitioners must use indicator groups to define spatial conservation priorities. Several studies have evaluated the effectiveness of indicator groups, but still little is known about the consistency in performance of these groups in different regions, which would allow their a priori selection.We systematically examined the effectiveness and the consistency of nine indicator groups in representing mammal species in two top-ranked Biodiversity Hotspots (BH: the Brazilian Cerrado and the Atlantic Forest. To test for group effectiveness we first found the best sets of sites able to maximize the representation of each indicator group in the BH and then calculated the average representation of different target species by the indicator groups in the BH. We considered consistent indicator groups whose representation of target species was not statistically different between BH. We called effective those groups that outperformed the target-species representation achieved by random sets of species. Effective indicator groups required the selection of less than 2% of the BH area for representing target species. Restricted-range species were the most effective indicators for the representation of all mammal diversity as well as target species. It was also the only group with high consistency.We show that several indicator groups could be applied as shortcuts for representing mammal species in the Cerrado and the Atlantic Forest to develop conservation plans, however, only restricted-range species consistently held as the most effective indicator group for such a task. This group is of particular importance in conservation planning as it captures high diversity of endemic and endangered species.

  4. Performance and consistency of indicator groups in two biodiversity hotspots.

    Science.gov (United States)

    Trindade-Filho, Joaquim; Loyola, Rafael Dias

    2011-01-01

    In a world limited by data availability and limited funds for conservation, scientists and practitioners must use indicator groups to define spatial conservation priorities. Several studies have evaluated the effectiveness of indicator groups, but still little is known about the consistency in performance of these groups in different regions, which would allow their a priori selection. We systematically examined the effectiveness and the consistency of nine indicator groups in representing mammal species in two top-ranked Biodiversity Hotspots (BH): the Brazilian Cerrado and the Atlantic Forest. To test for group effectiveness we first found the best sets of sites able to maximize the representation of each indicator group in the BH and then calculated the average representation of different target species by the indicator groups in the BH. We considered consistent indicator groups whose representation of target species was not statistically different between BH. We called effective those groups that outperformed the target-species representation achieved by random sets of species. Effective indicator groups required the selection of less than 2% of the BH area for representing target species. Restricted-range species were the most effective indicators for the representation of all mammal diversity as well as target species. It was also the only group with high consistency. We show that several indicator groups could be applied as shortcuts for representing mammal species in the Cerrado and the Atlantic Forest to develop conservation plans, however, only restricted-range species consistently held as the most effective indicator group for such a task. This group is of particular importance in conservation planning as it captures high diversity of endemic and endangered species.

  5. Effects of Sequences of Cognitions on Group Performance Over Time.

    Science.gov (United States)

    Molenaar, Inge; Chiu, Ming Ming

    2017-04-01

    Extending past research showing that sequences of low cognitions (low-level processing of information) and high cognitions (high-level processing of information through questions and elaborations) influence the likelihoods of subsequent high and low cognitions, this study examines whether sequences of cognitions are related to group performance over time; 54 primary school students (18 triads) discussed and wrote an essay about living in another country (32,375 turns of talk). Content analysis and statistical discourse analysis showed that within each lesson, groups with more low cognitions or more sequences of low cognition followed by high cognition added more essay words. Groups with more high cognitions, sequences of low cognition followed by low cognition, or sequences of high cognition followed by an action followed by low cognition, showed different words and sequences, suggestive of new ideas. The links between cognition sequences and group performance over time can inform facilitation and assessment of student discussions.

  6. Ballistic stretching increases flexibility and acute vertical jump height when combined with basketball activity.

    Science.gov (United States)

    Woolstenhulme, Mandy T; Griffiths, Christine M; Woolstenhulme, Emily M; Parcell, Allen C

    2006-11-01

    Stretching is often included as part of a warm-up procedure for basketball activity. However, the efficacy of stretching with respect to sport performance has come into question. We determined the effects of 4 different warm-up protocols followed by 20 minutes of basketball activity on flexibility and vertical jump height. Subjects participated in 6 weeks (2 times per week) of warm-up and basketball activity. The warm-up groups participated in ballistic stretching, static stretching, sprinting, or basketball shooting (control group). We asked 3 questions. First, what effect does 6 weeks of warm-up exercise and basketball play have on both flexibility and vertical jump height? We measured sit and reach and vertical jump height before (week -1) and after (week 7) the 6 weeks. Flexibility increased for the ballistic, static, and sprint groups compared to the control group (p vertical jump height did not change for any of the groups. Our second question was what is the acute effect of each warm-up on vertical jump height? We measured vertical jump immediately after the warm-up on 4 separate occasions during the 6 weeks (at weeks 0, 2, 4, and 6). Vertical jump height was not different for any group. Finally, our third question was what is the acute effect of each warm-up on vertical jump height following 20 minutes of basketball play? We measured vertical jump height immediately following 20 minutes of basketball play at weeks 0, 2, 4, and 6. Only the ballistic stretching group demonstrated an acute increase in vertical jump 20 minutes after basketball play (p basketball play, as it is beneficial to vertical jump performance.

  7. The effects of two methods of reflexology and stretching exercises on the severity of restless leg syndrome among hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Nahid Shahgholian

    2016-01-01

    Full Text Available Background: Restless leg syndrome prevalence is high among the patients undergoing hemodialysis. Due to several side effects of medicational treatments, the patients prefer non-medicational methods. Therefore, the present study aimed to investigate the effects of two methods of reflexology and stretching exercises on the severity of restless leg syndrome among patients undergoing hemodialysis. Materials and Methods: This study is a randomized clinical trial that was done on 90 qualified patients undergoing hemodialysis in selected hospitals of Isfahan, who were diagnosed with restless leg syndrome through standard restless leg syndrome questionnaire. They were randomly assigned by random number table to three groups: Reflexology, stretching exercises, and control groups through random allocation. Foot reflexology and stretching exercises were conducted three times a week for 30–40 min within straight 4 weeks. Data analysis was performed by SPSS version 18 using descriptive and inferential statistical analyses [one-way analysis of variance (ANOVA, paired t-test, and least significant difference (LSD post hoc test]. Results: There was a significant difference in the mean scores of restless leg syndrome severity between reflexology and stretching exercises groups, compared to control (P < 0.001, but there was no significant difference between the two study groups (P < 0.001. Changes in the mean score of restless leg syndrome severity were significantly higher in reflexology and stretching exercises groups compared to the control group (P < 0.001, but it showed no significant difference between reflexology massage and stretching exercises groups. Conclusions: Our obtained results showed that reflexology and stretching exercises can reduce the severity of restless leg syndrome. These two methods of treatment are recommended to the patients.

  8. Medical group affiliations: interorganizational relationships and organizational performance.

    Science.gov (United States)

    Rotarius, Timothy; Fottler, Myron D; Blair, John D

    2003-01-01

    The hyperturbulent health care environment is causing health care organizations to create interorganizational relationships (IORs). This article reports on a study of 686 medical groups that assessed how 11 types of IORs affected 7 dimensions of organizational performance. Organizational performance was ascertained through self-reported questions about performance relative to local market competitors. Respondents believed that, to varying degrees, all IORs lead to a competitive advantage over local competitors in all seven performance categories. There was no consistent pattern for either loose or tight linkages to be associated with superior performance. Consequently, loose linkages may be preferable to tighter linkages (i.e., membership in a fully integrated delivery system) that require higher levels of resource commitment.

  9. Stretch-minimising stream surfaces

    KAUST Repository

    Barton, Michael; Kosinka, Jin; Calo, Victor M.

    2015-01-01

    We study the problem of finding stretch-minimising stream surfaces in a divergence-free vector field. These surfaces are generated by motions of seed curves that propagate through the field in a stretch minimising manner, i.e., they move without stretching or shrinking, preserving the length of their arbitrary arc. In general fields, such curves may not exist. How-ever, the divergence-free constraint gives rise to these 'stretch-free' curves that are locally arc-length preserving when infinitesimally propagated. Several families of stretch-free curves are identified and used as initial guesses for stream surface generation. These surfaces are subsequently globally optimised to obtain the best stretch-minimising stream surfaces in a given divergence-free vector field. Our algorithm was tested on benchmark datasets, proving its applicability to incompressible fluid flow simulations, where our stretch-minimising stream surfaces realistically reflect the flow of a flexible univariate object. © 2015 Elsevier Inc. All rights reserved.

  10. Stretch-minimising stream surfaces

    KAUST Repository

    Barton, Michael

    2015-05-01

    We study the problem of finding stretch-minimising stream surfaces in a divergence-free vector field. These surfaces are generated by motions of seed curves that propagate through the field in a stretch minimising manner, i.e., they move without stretching or shrinking, preserving the length of their arbitrary arc. In general fields, such curves may not exist. How-ever, the divergence-free constraint gives rise to these \\'stretch-free\\' curves that are locally arc-length preserving when infinitesimally propagated. Several families of stretch-free curves are identified and used as initial guesses for stream surface generation. These surfaces are subsequently globally optimised to obtain the best stretch-minimising stream surfaces in a given divergence-free vector field. Our algorithm was tested on benchmark datasets, proving its applicability to incompressible fluid flow simulations, where our stretch-minimising stream surfaces realistically reflect the flow of a flexible univariate object. © 2015 Elsevier Inc. All rights reserved.

  11. Performance Agent Groups in the Promotion of Smart Economic Growth

    Directory of Open Access Journals (Sweden)

    Krūzmētra Maiga

    2017-12-01

    Full Text Available Any country is interested in economic growth regardless of its development level in any period; yet an increasingly important role in defining growth is played by the term ‘smart growth’. The EU development strategy until 2020 defines smart growth as a strategic objective. Smart growth does not take place automatically. It is affected both by the condition of the economic, social and natural environments and by subjective factors - the competence of performance agents. The present research distinguished three groups of rural space and regional performance agents: national institutions, local governments and communities of residents of the territories examined by the research. The research summarised the opinions of experts (Latvia n=171; Lithuania n=163 from the south-eastern part of Latvia and the north-eastern part of Lithuania with the purpose of assessing the contribution of the performance agent groups to the promotion of smart economic growth. The research aimed to identify the positive indications of the contribution made by each performance agent group as well as the largest problems affecting the promotion of smart economic growth in each country. Despite the fact that the sample groups were not representative (did not reflect the views of the entire population, the obtained survey data and the results of this analysis provided insight into the performance agents’ action ratings from the bottom-up position and allowed comparing the situations in Latvia and Lithuania. The research has become an urgent task in project No. 5.2.3 “Rural and Regional Development Processes and Opportunities in Latvia in the Context of Knowledge Economy” in National Research Programme 5.2. "Economic Transformation, Smart Growth, Governance and Legal Framework for the State and Society for Sustainable Development - a New Approach to the Creation of a Sustainable Learning Community: EKOSOC-LV”.

  12. Bruxism: Is There an Indication for Muscle-Stretching Exercises?

    Science.gov (United States)

    Gouw, Simone; de Wijer, Anton; Creugers, Nico Hj; Kalaykova, Stanimira I

    Bruxism is a common phenomenon involving repetitive activation of the masticatory muscles. Muscle-stretching exercises are a recommended part of several international guidelines for musculoskeletal disorders and may be effective in management of the jaw muscle activity that gives rise to bruxism. However, most studies of muscle-stretching exercises have mainly focused on their influence on performance (eg, range of motion, coordination, and muscle strength) of the limb or trunk muscles of healthy individuals or individuals with sports-related injuries. Very few have investigated stretching of the human masticatory muscles and none muscle-stretching exercises in the management of (sleep) bruxism. This article reviews the literature on muscle-stretching exercises and their potential role in the management of sleep bruxism or its consequences in the musculoskeletal system.

  13. The Performance Enhancement Group Program: Integrating Sport Psychology and Rehabilitation

    Science.gov (United States)

    Granito, Vincent J.; Hogan, Jeffery B.; Varnum, Lisa K.

    1995-01-01

    In an effort to improve the psychological health of the athlete who has sustained an injury, the Performance Enhancement Group program for injured athletes was created. This paper will offer a model for the Performance Enhancement Group program as a way to: 1) support the athlete, both mentally and physically; 2) deal with the demands of rehabilitation; and 3) facilitate the adjustments the athlete has to make while being out of the competitive arena. The program consists of responsibilities for professionals in sport psychology (ie, assessment/orientation, support, education, individual counseling, and evaluation) and athletic training (ie, organization/administration, recruitment and screening, support, application of techniques, and program compliance). The paper will emphasize that the success of the program is dependent on collaboration between professionals at all levels. PMID:16558357

  14. Communication as group process media of aircrew performance

    Science.gov (United States)

    Kanki, B. G.; Foushee, H. C.

    1989-01-01

    This study of group process was motivated by a high-fidelity flight simulator project in which aircrew performance was found to be better when the crew had recently flown together. Considering recent operating experience as a group-level input factor, aspects of the communication process between crewmembers (Captain and First Officer), were explored as a possible mediator to performance. Communication patterns were defined by a speech act typology adapted for the flightdeck setting and distinguished crews that had previously flown together (FT) from those that had not flown together (NFT). A more open communication channel with respect to information exchange and validation and greater First Officer participation in task-related topics was shown by FT crews while NFT crews engaged in more non-task discourse, a speech mode less structured by roles and probably serving a more interpersonal function. Relationships between the speech categories themselves, representing linguistic, and role-related interdependencies provide guidelines for interpreting the primary findings.

  15. What makes a 'good group'? Exploring the characteristics and performance of undergraduate student groups.

    Science.gov (United States)

    Channon, S B; Davis, R C; Goode, N T; May, S A

    2017-03-01

    Group work forms the foundation for much of student learning within higher education, and has many educational, social and professional benefits. This study aimed to explore the determinants of success or failure for undergraduate student teams and to define a 'good group' through considering three aspects of group success: the task, the individuals, and the team. We employed a mixed methodology, combining demographic data with qualitative observations and task and peer evaluation scores. We determined associations between group dynamic and behaviour, demographic composition, member personalities and attitudes towards one another, and task success. We also employed a cluster analysis to create a model outlining the attributes of a good small group learning team in veterinary education. This model highlights that student groups differ in measures of their effectiveness as teams, independent of their task performance. On the basis of this, we suggest that groups who achieve high marks in tasks cannot be assumed to have acquired team working skills, and therefore if these are important as a learning outcome, they must be assessed directly alongside the task output.

  16. Evaluation of risk management and financial performance of BMW Group

    OpenAIRE

    Mysina, Amira

    2017-01-01

    Effective risk and financial management possess a great challenge for the multinational companies operating globally. Despite the increasing development of diverse hedging strategies against foreign exchange risk, global firms cannot fully foresee and measure the degree of the impact of foreign currency fluctuations. This paper aims to evaluate the exchange risk management and financial performance of the BMW Group from the year 2005 to 2016. Moreover, this paper is devoted to provide explana...

  17. Interset stretching does not influence the kinematic profile of consecutive bench-press sets.

    Science.gov (United States)

    García-López, David; Izquierdo, Mikel; Rodríguez, Sergio; González-Calvo, Gustavo; Sainz, Nuria; Abadía, Olaia; Herrero, Azael J

    2010-05-01

    This study was undertaken to examine the role of interset stretching on the time course of acceleration portion AP and mean velocity profile during the concentric phase of 2 bench-press sets with a submaximal load (60% of the 1 repetition maximum). Twenty-five college students carried out, in 3 different days, 2 consecutive bench-press sets leading to failure, performing between sets static stretching, ballistic stretching, or no stretching. Acceleration portion and lifting velocity patterns of the concentric phase were not altered during the second set, regardless of the stretching treatment performed. However, when velocity was expressed in absolute terms, static stretching reduced significantly (p velocity during the second set compared to the first one. Therefore, if maintenance of a high absolute velocity over consecutive sets is important for training-related adaptations, static stretching should be avoided or replaced by ballistic stretching.

  18. The Effect of Implied Performer Age and Group Membership on Evaluations of Music Performances

    Science.gov (United States)

    Harrington, Ann M.

    2018-01-01

    This study examined the effects of implied performer age and group membership on listeners' evaluations of music performances. Undergraduate music majors (n = 23), nonmusic majors (n = 17), and members of a New Horizons ensemble (n = 16) were presented with six 30-second excerpts of concert band performances. Excerpts were presented to all…

  19. Evaluating Motoric Performance of 10 - 12 Age Group Football Players

    Directory of Open Access Journals (Sweden)

    Mehmet KUMARTAŞLI

    2014-08-01

    Full Text Available The aim of this study is to evaluate motoric perfromance of 10 - 12 age group football players. Akdeniz University tiny football team joined as experiment group and 80. Yıl Cumhuriyet Grammar School football team joined to the study as control group. An exercise programme with educational game format considering physical capacities and develeopment features was applied to the student as 8 weeks, 3 days a week. Standing long jump, flexibilty, 20 m. speed, handgrip strength, arm pull, vert ical jump, 10x5 shuttle run and leg strength tests were applied to the students. Handled data were compared at SPSS 10 statistic programme by using Independent Sample t Test. Students’ lenght and weight measurements were calculated. As a result of measurem ents, there were not found diffrences between experimental and control group’s standing long jump, flexibilty, 20 m. speed, handgrip strength, a vertical jump, 10x5 shuttle run and leg strength tests (p>0,05; but in arm pull test, statistically difference was found (p<0,01. While evaluating the physical performance in cihldren and adolescents, growth process is had to be considered. The results of football players that exercise regularly from small ages at physical and physiologic measurements have an importance according to their age. Performance observed in children is sudden and temporary. There are a few studies in the literature about negative psycological effects of starting trainings in early ages.

  20. EFFICACY OF CYRIAX PHYSIOTHERAPY VERSUS ECCENTRIC STRENGTHENING AND STRETCHING EXERCISES IN CHRONIC LATERAL EPICONDYLITIS PATIENTS

    Directory of Open Access Journals (Sweden)

    Madhusmita Koch

    2015-10-01

    Full Text Available Background: Lateral Epicondylitis is the most common lesion of the elbow, affecting the tendinous origin of the wrist extensors. Although conservative treatment of this condition has been the subject of numerous studies, there is no agreement as to the most effective management strategy. Therefore, this study was designed to compare the efficacy of Cyriax physiotherapy Versus Eccentric Strengthening and Stretching exercises in reducing the pain and improving the grip strength and functional status of the affected extremity in chronic lateral epicondylitis. Method: An experimental study design, 60 subjects meeting the inclusion criteria were selected for the study and were randomly assigned into two groups: Group A (N=30 received Cyriax Physiotherapy and Group B(N=30 received Eccentric strengthening and static stretching of Extensor Carpi Radialis Brevis. Low Level Laser Therapy was a common treatment for both the groups. After 4 weeks of treatment, assessment was performed using Visual Analogue Scale (VAS, Hand Held Dynamometer (HHD and Patient Rated Tennis Elbow Evaluation Questionnaire (PRTEE at 0 week and at the end of 4 weeks. Results: Data analysis revealed that there is no statistically significant difference between the groups in VAS, HHD and PRTEE scores i.e. average improvement post treatment in both the groups are equal, but within group comparisons showed significant improvements in both the groups. Conclusion: The efficacy of Cyriax Physiotherapy is equal to Eccentric Strengthening and Stretching Exercises in chronic lateral epicondylitis.

  1. Atomic Stretch: Optimally bounded real-time stretching and beyond

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Nielsen, Jannik Boll

    2016-01-01

    Atomic Stretch is a plugin for your preferred Adobe video editing tool, allowing real-time smooth and optimally bounded retarget-ting from and to any aspect ratio. The plugin allows preserving of high interest pixels through a protected region, attention redirection through color-modification, co......Atomic Stretch is a plugin for your preferred Adobe video editing tool, allowing real-time smooth and optimally bounded retarget-ting from and to any aspect ratio. The plugin allows preserving of high interest pixels through a protected region, attention redirection through color...

  2. Acute Whole-Body Vibration does not Facilitate Peak Torque and Stretch Reflex in Healthy Adults

    Directory of Open Access Journals (Sweden)

    Ella W. Yeung

    2013-03-01

    Full Text Available The acute effect of whole-body vibration (WBV training may enhance muscular performance via neural potentiation of the stretch reflex. The purpose of this study was to investigate if acute WBV exposure affects the stretch induced knee jerk reflex [onset latency and electromechanical delay (EMD] and the isokinetic knee extensor peak torque performance. Twenty-two subjects were randomly assigned to the intervention or control group. The intervention group received WBV in a semi-squat position at 30° knee flexion with an amplitude of 0.69 mm, frequency of 45 Hz, and peak acceleration of 27.6 m/s2 for 3 minutes. The control group underwent the same semii-squatting position statically without exposure of WBV. Two-way mixed repeated measures analysis of variance revealed no significant group effects differences on reflex latency of rectus femoris (RF and vastus lateralis (VL; p = 0.934 and 0.935, respectively EMD of RF and VL (p = 0.474 and 0.551, respectively and peak torque production (p = 0.483 measured before and after the WBV. The results of this study indicate that a single session of WBV exposure has no potentiation effect on the stretch induced reflex and peak torque performance in healthy young adults.

  3. Efficacy of hamstring stretching programs in schoolchildren. A systematic review

    Directory of Open Access Journals (Sweden)

    Carlos-Alberto BECERRA FERNANDEZ

    2017-03-01

    Full Text Available The main purpose of the present review was to examine the scientific literature on the effects of physical education-based stretching programs on hamstring extensibility in schoolchildren aged 6-11 years. For this purpose relevant studies were searched from ten electronic databases dated up through May 2015. Of the 25 potentially relevant articles identified and retrieved for more detailed evaluation, only eight studies were included in the present review because they met the inclusion criteria. The overall results showed that incorporating hamstring stretching as a part of physical education classes produces a significant improvement in the scores of the tests: straight leg raise and classic sit-and-reach, for the experimental groups, but not for control groups. Stretching programs can be included in Physical Education classes, specifically during the warm-up and the cool down periods in order to improve hamstring extensibility. Although it seems that the stretching exercises in the warm-up period could be less effective in gaining flexibility in school children. Studies that use a stretching volume between 4 and 7 minutes per session and 2-4 training classes per week, obtain statistically significant improvements on the levels of hamstring flexibility in the experimental groups. However, after a five-week detraining period, children revert back to their initial flexibility levels. Therefore, it seems appropriate that physical education teachers should implement stretching programs to improve the students´ flexibility during the Physical Education classes.

  4. The effect of warm-up, static stretching and dynamic stretching on hamstring flexibility in previously injured subjects.

    LENUS (Irish Health Repository)

    O'Sullivan, Kieran

    2009-01-01

    BACKGROUND: Warm-up and stretching are suggested to increase hamstring flexibility and reduce the risk of injury. This study examined the short-term effects of warm-up, static stretching and dynamic stretching on hamstring flexibility in individuals with previous hamstring injury and uninjured controls. METHODS: A randomised crossover study design, over 2 separate days. Hamstring flexibility was assessed using passive knee extension range of motion (PKE ROM). 18 previously injured individuals and 18 uninjured controls participated. On both days, four measurements of PKE ROM were recorded: (1) at baseline; (2) after warm-up; (3) after stretch (static or dynamic) and (4) after a 15-minute rest. Participants carried out both static and dynamic stretches, but on different days. Data were analysed using Anova. RESULTS: Across both groups, there was a significant main effect for time (p < 0.001). PKE ROM significantly increased with warm-up (p < 0.001). From warm-up, PKE ROM further increased with static stretching (p = 0.04) but significantly decreased after dynamic stretching (p = 0.013). The increased flexibility after warm-up and static stretching reduced significantly (p < 0.001) after 15 minutes of rest, but remained significantly greater than at baseline (p < 0.001). Between groups, there was no main effect for group (p = 0.462), with no difference in mean PKE ROM values at any individual stage of the protocol (p > 0.05). Using ANCOVA to adjust for the non-significant (p = 0.141) baseline difference between groups, the previously injured group demonstrated a greater response to warm-up and static stretching, however this was not statistically significant (p = 0.05). CONCLUSION: Warm-up significantly increased hamstring flexibility. Static stretching also increased hamstring flexibility, whereas dynamic did not, in agreement with previous findings on uninjured controls. The effect of warm-up and static stretching on flexibility was greater in those with reduced

  5. Effect of stretching and proprioceptive loading in hand function among patients with cerebellar tremor

    Directory of Open Access Journals (Sweden)

    Hariharasudhan Ravichandran

    2016-01-01

    Full Text Available Background and Objective: Tremor, the most common form of abnormal involuntary movement, affects the performance of activities of daily living. Evidence on effective form of physiotherapy techniques which can help manage intentional tremor and improve hand function among cerebellar dysfunction patients in inconclusive. Hence, this study aims to establish the effectiveness of stretching and proprioceptive loading among cerebellar patients with intentional tremors. The objective of this study is to compare the efficacy of stretching and proprioceptive loading among patients with cerebellar intention tremor. Materials and Methods: A total of thirty patients with intention tremor due to cerebellar lesion were recruited for this study. They were randomized into two groups, Group I received stretching exercise and Group II received proprioceptive loading exercise. Pre- and post-test outcome measures were taken at the end of duration of 3 weeks intervention. Outcome measures were Fahn's tremor rating scale and nine hole peg test. Results: Statistical analyses were done by McNemar test, Wilcoxon's signed rank test, and Mann–Whitney test. Post-test scores of both groups were compared and found that Group II treated with proprioceptive loading exercise had higher significant result than the group treated with strengthening exercise program. Conclusion: Proprioceptive loading exercise has demonstrated signifi cant effect on reducing cerebellar tremor and improving muscle coordination in reaching activities.

  6. TIBER II/ETR: Nuclear Performance Analysis Group Report

    International Nuclear Information System (INIS)

    1987-09-01

    A Nuclear Performance Analysis Group was formed to develop the nuclear technology mission of TIBER-II under the leadership of Argonne National Laboratory reporting to LLNL with major participation by the University of California - Los Angeles (test requirements, R and D needs, water-cooled test modules, neutronic tests). Additional key support was provided by GA Technologies (helium-cooled test modules), Hanford Engineering Development Laboratory (material-irradiation tests), Sandia National Laboratory - Albuquerque (high-heat-flux component tests), and the Idaho National Engineering Laboratory (safety tests). Support also was provided by Rennselaer Polytechnic Institute, Grumman Aerospace Corporation, and the Canadian Fusion Fuels Technology Program. This report discusses these areas and provides a schedule for their completion

  7. Diagnosis-Related Groups (DRG and Hospital Business Performance Management

    Directory of Open Access Journals (Sweden)

    Szynkiewicz Piotr

    2014-12-01

    Full Text Available The goal of this article is to present the possibility of using Diagnosis- Related Groups (DRG in the hospital management process and to analyse the need for business performance management on the part of hospital management staff. The following research methods were used: literature analysis, case studies, and poll analysis. It is not possible to increase the effectiveness of operation of healthcare entities without increasing the importance of IT systems and using DRG more effectively in the management process. Training users in IT and the use of DRGs is important to achieving hospital effectiveness. The increased importance of analyses and planning in a hospital should be reflected in the organisational structure of service providers. Hospital controllers should have a similar role to those present in most companies in other industries.

  8. The effect of warm-ups with stretching on the isokinetic moments of collegiate men.

    Science.gov (United States)

    Park, Hyoung-Kil; Jung, Min-Kyung; Park, Eunkyung; Lee, Chang-Young; Jee, Yong-Seok; Eun, Denny; Cha, Jun-Youl; Yoo, Jaehyun

    2018-02-01

    Performing warm-ups increases muscle temperature and blood flow, which contributes to improved exercise performance and reduced risk of injuries to muscles and tendons. Stretching increases the range of motion of the joints and is effective for the maintenance and enhancement of exercise performance and flexibility, as well as for injury prevention. However, stretching as a warm-up activity may temporarily decrease muscle strength, muscle power, and exercise performance. This study aimed to clarify the effect of stretching during warm-ups on muscle strength, muscle power, and muscle endurance in a nonathletic population. The subjects of this study consisted of 13 physically active male collegiate students with no medical conditions. A self-assessment questionnaire regarding how well the subjects felt about their physical abilities was administered to measure psychological readiness before and after the warm-up. Subjects performed a non-warm-up, warm-up, or warm-up regimen with stretching prior to the assessment of the isokinetic moments of knee joints. After the measurements, the respective variables were analyzed using nonparametric tests. First, no statistically significant intergroup differences were found in the flexor and extensor peak torques of the knee joints at 60°/sec, which were assessed to measure muscle strength. Second, no statistically significant intergroup differences were found in the flexor and extensor peak torques of the knee joints at 180°/sec, which were assessed to measure muscle power. Third, the total work of the knee joints at 240°/sec, intended to measure muscle endurance, was highest in the aerobic-stretch-warm-ups (ASW) group, but no statistically significant differences were found among the groups. Finally, the psychological readiness for physical activity according to the type of warm-up was significantly higher in ASW. Simple stretching during warm-ups appears to have no effect on variables of exercise physiology in nonathletes

  9. The effect of warm-up, static stretching and dynamic stretching on hamstring flexibility in previously injured subjects

    Directory of Open Access Journals (Sweden)

    Murray Elaine

    2009-04-01

    Full Text Available Abstract Background Warm-up and stretching are suggested to increase hamstring flexibility and reduce the risk of injury. This study examined the short-term effects of warm-up, static stretching and dynamic stretching on hamstring flexibility in individuals with previous hamstring injury and uninjured controls. Methods A randomised crossover study design, over 2 separate days. Hamstring flexibility was assessed using passive knee extension range of motion (PKE ROM. 18 previously injured individuals and 18 uninjured controls participated. On both days, four measurements of PKE ROM were recorded: (1 at baseline; (2 after warm-up; (3 after stretch (static or dynamic and (4 after a 15-minute rest. Participants carried out both static and dynamic stretches, but on different days. Data were analysed using Anova. Results Across both groups, there was a significant main effect for time (p 0.05. Using ANCOVA to adjust for the non-significant (p = 0.141 baseline difference between groups, the previously injured group demonstrated a greater response to warm-up and static stretching, however this was not statistically significant (p = 0.05. Conclusion Warm-up significantly increased hamstring flexibility. Static stretching also increased hamstring flexibility, whereas dynamic did not, in agreement with previous findings on uninjured controls. The effect of warm-up and static stretching on flexibility was greater in those with reduced flexibility post-injury, but this did not reach statistical significance. Further prospective research is required to validate the hypothesis that increased flexibility improves outcomes. Trial Registration ACTRN12608000638336

  10. Acute effects of active isolated stretching on vertical jump ...

    African Journals Online (AJOL)

    The purpose of the study was to determine the acute effects of active isolated stretching on muscular peak power production. Sixty healthy, physically active volunteers (aged 18-28) participated as subjects in this study. Subjects were randomly assigned to two groups; the control group and the experimental group. Subjects ...

  11. Soleus stretch reflex during cycling

    DEFF Research Database (Denmark)

    Grey, Michael James; Pierce, C. W.; Milner, T. E.

    2001-01-01

    The modulation and strength of the human soleus short latency stretch reflex was investigated by mechanically perturbing the ankle during an unconstrained pedaling task. Eight subjects pedaled at 60 rpm against a preload of 10 Nm. A torque pulse was applied to the crank at various positions durin...

  12. Optical tweezers stretching of chromatin

    NARCIS (Netherlands)

    Pope, L.H.; Bennink, Martin L.; Greve, Jan

    2003-01-01

    Recently significant success has emerged from exciting research involving chromatin stretching using optical tweezers. These experiments, in which a single chromatin fibre is attached by one end to a micron-sized bead held in an optical trap and to a solid surface or second bead via the other end,

  13. Guidelines for Stretch Flanging Advanced High Strength Steels

    International Nuclear Information System (INIS)

    Sriram, S.; Chintamani, J.

    2005-01-01

    Advanced High Strength Steels (AHSS) are currently being considered for use in closure and structural panels in the automotive industry because of their high potential for affordable weight reduction and improved performance. AHSS such as dual phase steels are currently being used in some vehicle platforms. From a manufacturing perspective, stretch flanging during stamping is an important deformation mode requiring careful consideration of geometry and the die process. This paper presents some geometric and process guidelines for stretch flanging AHSS. Hole expansion experiments were conducted to determine the failure limit for a sheared edge condition. Effects of punching clearance, prestrain and prior strain path on hole expansion were explored in these experiments. In addition, dynamic explicit FE calculations using LS-DYNA were also conducted for a typical stretch flange by varying some key geometric parameters. The experimental and FEA results were then analyzed to yield process and geometric guidelines to enable successful stretch flanging of AHSS

  14. Measurement of Resistive Plantar Flexion Torque of the Ankle during Passive Stretch in Healthy Subjects and Patients with Poststroke Hemiplegia.

    Science.gov (United States)

    Mizuno, Shiho; Sonoda, Shigeru; Takeda, Kotaro; Maeshima, Shinichiro

    2016-04-01

    Quantification of increased muscle tone for patients with spasticity has been performed to date using various devices to replace the manual scales, such as the modified Ashworth scale or the Tardieu scale. We developed a device that could measure resistive plantar flexion (PF) torque of the ankle during passive dorsiflexion (DF) as an indicator of muscle tone of ankle plantar flexors. The primary objective was to explore the test-retest intrarater reliability of a custom-built device. Participants were 11 healthy subjects (7 men, 4 women; mean age 47.0 years) and 22 patients with poststroke hemiplegia (11 hemorrhagic, 11 ischemic; 14 men, 8 women; mean age 57.2 years). The device was affixed to the ankle. Subjects were seated with knees either flexed or extended. The ankle was passively dorsiflexed from 20° of PF to more than 10° of DF at 5°/second (slow stretch) or 90°/second (fast stretch). Angle and torque were measured twice during the stretches. The intraclass correlation coefficients (ICCs) of torque at 10° of DF (T10) in the 4 conditions-slow and fast stretches with knee flexed or extended-were calculated. The T10 ICCs of the 4 conditions were .95-.99 in both groups. The healthy subjects showed significantly higher T10 of knee extension than of knee flexion during slow and fast stretches. The patients showed increased velocity-dependent torque during fast stretches. Excellent reliability was observed. The device is suitable for measuring resistive PF torque during passive stretch in a flexed knee condition. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  15. Acute effects of 15min static or contract-relax stretching modalities on plantar flexors neuromuscular properties.

    Science.gov (United States)

    Babault, Nicolas; Kouassi, Blah Y L; Desbrosses, Kevin

    2010-03-01

    The present study aimed to investigate the immediate effects of 15 min static or sub-maximal contract-relax stretching modalities on the neuromuscular properties of plantar flexor muscles. Ten male volunteers were tested before and immediately after 15 min static or contract-relax stretching programs of plantar flexor muscles (20 stretches). Static stretching consisted in 30s stretches to the point of discomfort. For the contract-relax stretching modality, subjects performed 6s sub-maximal isometric plantar flexion before 24s static stretches. Measurements included maximal voluntary isometric torque (MVT) and the corresponding electromyographic activity of soleus (SOL) and medial gastrocnemius (MG) muscles (RMS values), as well as maximal peak torque (Pt) elicited at rest by single supramaximal electrical stimulation of the tibial nerve. After 15 min stretching, significant MVT and SOL RMS decreases were obtained (-6.9+/-11.6% and -6.5+/-15.4%, respectively). No difference was obtained between stretching modalities. Pt remained unchanged after stretching. MG RMS changes were significantly different between stretching modalities (-9.4+/-18.3% and +3.5+/-11.6% after static and contract-relax stretching modalities, respectively). These findings indicated that performing 15 min static or contract-relax stretching had detrimental effects on the torque production capacity of plantar flexor muscles and should be precluded before competition. Mechanisms explaining this alteration seemed to be stretch modality dependent. Copyright 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  16. 600 Volt Stretched Lens Array for Solar Electric Propulsion, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — ENTECH, Auburn, NASA, and others have recently developed a new space photovoltaic array called the Stretched Lens Array (SLA), offering unprecedented performance...

  17. Time stretch and its applications

    Science.gov (United States)

    Mahjoubfar, Ata; Churkin, Dmitry V.; Barland, Stéphane; Broderick, Neil; Turitsyn, Sergei K.; Jalali, Bahram

    2017-06-01

    Observing non-repetitive and statistically rare signals that occur on short timescales requires fast real-time measurements that exceed the speed, precision and record length of conventional digitizers. Photonic time stretch is a data acquisition method that overcomes the speed limitations of electronic digitizers and enables continuous ultrafast single-shot spectroscopy, imaging, reflectometry, terahertz and other measurements at refresh rates reaching billions of frames per second with non-stop recording spanning trillions of consecutive frames. The technology has opened a new frontier in measurement science unveiling transient phenomena in nonlinear dynamics such as optical rogue waves and soliton molecules, and in relativistic electron bunching. It has also created a new class of instruments that have been integrated with artificial intelligence for sensing and biomedical diagnostics. We review the fundamental principles and applications of this emerging field for continuous phase and amplitude characterization at extremely high repetition rates via time-stretch spectral interferometry.

  18. The Impact of Study Groups and Roommates on Academic Performance

    OpenAIRE

    Tarun Jain; Mudit Kapoor

    2015-01-01

    This paper uses random assignment of students to investigate the impact of study groups and roommates on academic achievement. We find that informal social interaction with roommates has a significant positive impact on academic achievement, while study group peers have no discernible impact, a result driven by group heterogeneity in ability. We also find that lower-ability students benefit from high-ability students but not vice versa. © 2015 The President and Fellows of Harvard College and...

  19. [Performance of self-help groups and their economic evaluation].

    Science.gov (United States)

    Engelhardt, H D; Trojan, A; Nickel, S

    2009-01-01

    Hoffmann von Fallersleben is quoted with the sentence "Self-help is worthwhile, because it does not demand anything from others". This sounds catchy; it is, however, wrong: Self-help groups ask for support, particularly for financial resources for the work of either individual, highly organized self-help associations or for general support of self-help groups via local contact and information centers ("contact points for self-help groups"). With this request for economic "investments" in self-help, the question arises whether this is profitable for the country, the local authority or the social health insurance. In principle, the initial answer to this is: yes, the work of self-help groups is worthwhile for a single person, but also for the larger community, as various kinds of services are provided by self-help groups and organizations. Despite many surveys of members or co-operation partners which show positive effects of self-help groups, the question remains whether services of self-help groups can be measured and economically evaluated. The socio- political question regarding funding is closely connected to the idea of an economic evaluation of self-help groups. The aim of this article is to summarize and discuss which empiric approaches and findings are available on this subject. The monetary value for the work done per member of self-help groups and year lies between approximately 700 and 900 EUR.

  20. Analysis of a filament stretching rheometer

    DEFF Research Database (Denmark)

    Kolte, Mette Irene; Rasmussen, Henrik K.; Hassager, Ole

    1996-01-01

    A finite element analysis of the stretching filament rheometer of Tirtaadmadja and Sridhar (1993) is presenetd. Simulations of the stretching of a filament of the polymet test solution, fluid A, between two plates are shown.......A finite element analysis of the stretching filament rheometer of Tirtaadmadja and Sridhar (1993) is presenetd. Simulations of the stretching of a filament of the polymet test solution, fluid A, between two plates are shown....

  1. What Makes a "Good Group"? Exploring the Characteristics and Performance of Undergraduate Student Groups

    Science.gov (United States)

    Channon, S. B.; Davis, R. C.; Goode, N. T.; May, S. A.

    2017-01-01

    Group work forms the foundation for much of student learning within higher education, and has many educational, social and professional benefits. This study aimed to explore the determinants of success or failure for undergraduate student teams and to define a "good group" through considering three aspects of group success: the task, the…

  2. BSDB: the Biomolecule Stretching Database

    Science.gov (United States)

    Cieplak, Marek; Sikora, Mateusz; Sulkowska, Joanna I.; Witkowski, Bartlomiej

    2011-03-01

    Despite more than a decade of experiments on single biomolecule manipulation, mechanical properties of only several scores of proteins have been measured. A characteristic scale of the force of resistance to stretching, Fmax , has been found to range between ~ 10 and 480 pN. The Biomolecule Stretching Data Base (BSDB) described here provides information about expected values of Fmax for, currently, 17 134 proteins. The values and other characteristics of the unfolding proces, including the nature of identified mechanical clamps, are available at www://info.ifpan.edu.pl/BSDB/. They have been obtained through simulations within a structure-based model which correlates satisfactorily with the available experimental data on stretching. BSDB also lists experimental data and results of the existing all-atom simulations. The database offers a Protein-Data-Bank-wide guide to mechano-stability of proteins. Its description is provided by a forthcoming Nucleic Acids Research paper. Supported by EC FUNMOL project FP7-NMP-2007-SMALL-1, and European Regional Development Fund: Innovative Economy (POIG.01.01.02-00-008/08).

  3. Comparison of impacts of friction massage, stretching exercises and analgesics on pain relief in primary fibromyalgia syndrome: a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Amanollahi A

    2013-01-01

    Full Text Available Background: Stretching exercises and massage therapy are both suggested for pain relief in fibromyalgia syndrome. Previous studies have not proved their superiority over each other. This study compared the therapeutic effects of friction massage, stretching exercises, and analgesics on pain relief in patients with fibromyalgia syndrome.Methods: We evaluated 129 female patients with the diagnosis of primary fibromyalgia visited at the physical medicine clinics of Baqiyatallah Hospital in Tehran, Iran during 2010- 2011. Patients were randomly divided into three groups: the first group received 400 mg ibuprofen P.O. (3 times per day and 25 mg nortriptyline (daily P.O. as analgesic, the second group was treated by friction massage and the third group performed stretching exercises. Patients were assessed three times (initially, after one and four weeks by visual analogue scale (VAS.Results: The mean age of participants was 60.46 years. The mean age in each treatment group was 46.66 years in medication group, 46.73 years in stretching group and 46.65 years in friction massage group. Changes in VAS score over 4 weeks were 2.4, 3.1 and 1.9, in the first, second, and third groups, respectively. The changes in VAS were significantly different in the first and second groups rather than the controls (P<0.05.Conclusion: The effect of stretch exercise on pain relief was similar to analgesics, but it was more effective than friction massage. Moreover, the therapeutic effect of stretching exercise on pain relief upon four weeks was more permanent than friction massage but it was similar to analgesics.

  4. Effect of Ankle Positioning During Hamstring Stretches for Improving Straight Leg Hip Flexion Motion.

    Science.gov (United States)

    Laudner, Kevin G; Benjamin, Peter J; Selkow, Noelle M

    2016-03-01

    To compare the effects of stretching the hamstrings with the ankle in either a plantar-flexed (PF) or dorsiflexed (DF) position for improving straight leg hip flexion range of motion (ROM) over a 4-week period. Randomized, single-blinded, pretest, posttest design. Athletic training facility. Each limb of 34 asymptomatic individuals (15 males, 19 females) was randomly assigned to one of the 3 groups. Twenty-four limbs received hamstring stretches with the ankle in DF, 24 limbs received hamstring stretches with the ankle in PF, and 20 limbs received no stretch (control). Ankle position (PF, DF) during hamstring stretching. We measured pretest and posttest passive straight leg hip flexion ROM with the test ankle in a neutral position. For the intervention groups, the test limb was passively stretched with the ankle held in end range DF or PF for their respective group. Each stretch was held for 30 seconds for a total of 3 applications. Two treatment sessions were completed per week for a total of 4 weeks. The control limbs received no stretching during the 4-week period. We conducted 1-way analyses of covariance to determine significant changes in ROM between groups (P hamstrings in either PF or DF improve straight leg hip ROM compared with a control group. The results of this study should be considered by clinicians when determining the optimal stretching techniques aimed at increasing hamstring length.

  5. Cultural diversity and work-group performance : Detecting the rules

    NARCIS (Netherlands)

    Girndt, T.

    2000-01-01

    With greater levels of international cooperation, work-groups are increasingly composed of members from different cultures. These groups often suffer from communication problems; however, research suggests that they also benefit from their members cultural diversity and generate higher ranges of

  6. On the comparison of group performance with categorical data.

    Directory of Open Access Journals (Sweden)

    Carmen Herrero

    Full Text Available There are many different evaluation problems that involve several groups (societies, firms or institutions whose members can be classified into ordered categories, pursuant to their characteristics or their achievements. This paper addresses these types of problems and provides an evaluation criterion based on the distribution of the agents across categories. The starting point is that of dominance relations in pair-wise comparisons. We say that group i dominates group j when the expected category of a member of i is higher than the expected category of a member of j. We introduce the notion of relative advantage of a group to extend this principle to multi-group comparisons and show that there is a unique evaluation function that ranks all groups consistently in terms of this criterion. This function associates to each evaluation problem the (unique dominant eigenvector of a matrix whose entries describe the dominance relations between groups in pair-wise comparisons. The working of the model is illustrated by means of three different applications.

  7. Performance of Group Communication Over Ad-Hoc Networks

    National Research Council Canada - National Science Library

    Mosko, Marc; Garcia-Luna-Aceves, J. J

    2002-01-01

    ... through a network of cluster trees, where a spanning tree joins groups of fully connected nodes. Through numerical analysis and simulations in GloMoSim, we show throughput, goodput, and loss rates for reliable and unreliable networks...

  8. Group Performance in Military Scenarios Under Deceptive Conditions

    National Research Council Canada - National Science Library

    Hass, Michael

    2004-01-01

    .... One hundred and eight participants were grouped into teams of three, given similar instructions but different goals, and asked to play a cooperative game called StrikeCOM that mimics the intelligence...

  9. Group Performance in Military Scenarios Under Deceptive Conditions

    National Research Council Canada - National Science Library

    Hass, Michael

    2004-01-01

    ... (warnings of player deception) relate to perceptions of deception and task difficulty and in turn how these perceptions relate to the final group game scores in a cooperative effort with conflicting goals...

  10. Endovascular rescue method for undesirably stretched coil.

    Science.gov (United States)

    Cho, Jae Hoon

    2014-10-01

    Undesirable detachment or stretching of coils within the parent artery during aneurysm embolization can be related with thrombus formation, which can be caused occlusion of parent artery or embolic event(s). To escape from this situation, several rescue methods have been reported. A case with undesirably stretched coil in which another rescue method was used, is presented. When the stretched coil is still located in the coil delivery microcatheter, the stretched coil can be removed safely using a snare and a handmade monorail microcatheter. After a snare is lodged in the handmade monorail microcatheter, the snare is introduced over the coil delivery micorcatheter and located in the distal part of the stretched coil. After then, the handmade monorail microcatheter captures the stretched coil and the snare as one unit. This technique using a handmade monorail microcatheter and a snare can be a good rescue modality for the undesirably stretched coil, still remained within the coil delivery microcatheter.

  11. The Role of Focus Groups with Other Performance Measurement Methods.

    Science.gov (United States)

    Hart, Elizabeth

    Huddersfield University Library (England) has undertaken a wide range of evaluative studies of its services and systems, using various data collection techniques such as: user surveys; exit interviews; online and CD-ROM analysis; benchmarking; user groups; staffing and staff development evaluation; suggestion sheets; student project work; group…

  12. Group cohesion, task performance, and the experimenter expectancy effect.

    NARCIS (Netherlands)

    Hoogstraten, J.; Vorst, H.C.M.

    1978-01-01

    Studied the effects of cohesion on task fulfillment and explored the influence of task fulfillment on the initial level of cohesion. Within 4-person groups of undergraduates, cohesion was manipulated successfully by a triple procedure. The level of cohesion was ascertained directly after the

  13. Adaptation of the dermal collagen structure of human skin and scar tissue in response to stretch: An experimental study

    NARCIS (Netherlands)

    Verhaegen, Pauline D.; Schouten, Hennie J.; Tigchelaar-Gutter, Wikky; van Marle, Jan; van Noorden, Cornelis J.; Middelkoop, Esther; van Zuijlen, Paul P.

    2012-01-01

    Surgeons are often faced with large defects that are difficult to close. Stretching adjacent skin can facilitate wound closure. In clinical practice, intraoperative stretching is performed in a cyclical or continuous fashion. However, exact mechanisms of tissue adaptation to stretch remain unclear.

  14. Bending and stretching of plates

    CERN Document Server

    Mansfield, E H; Hemp, W S

    1964-01-01

    The Bending and Stretching of Plates deals with elastic plate theory, particularly on small- and large-deflexion theory. Small-deflexion theory concerns derivation of basic equations, rectangular plates, plates of various shapes, plates whose boundaries are amenable to conformal transformation, plates with variable rigidity, and approximate methods. Large-deflexion theory includes general equations and some exact solutions, approximate methods in large-deflexion theory, asymptotic large-deflexion theories for very thin plates. Asymptotic theories covers membrane theory, tension field theory, a

  15. Stretching of macromolecules and proteins

    International Nuclear Information System (INIS)

    Strick, T R; Dessinges, M-N; Charvin, G; Dekker, N H; Allemand, J-F; Bensimon, D; Croquette, V

    2003-01-01

    In this paper we review the biophysics revealed by stretching single biopolymers. During the last decade various techniques have emerged allowing micromanipulation of single molecules and simultaneous measurements of their elasticity. Using such techniques, it has been possible to investigate some of the interactions playing a role in biology. We shall first review the simplest case of a non-interacting polymer and then present the structural transitions in DNA, RNA and proteins that have been studied by single-molecule techniques. We shall explain how these techniques permit a new approach to the protein folding/unfolding transition

  16. Do Cognitive Styles Affect the Performance of System Development Groups?

    Science.gov (United States)

    1986-03-21

    that a person is classified as one of 16 possible types: ISTJ, iSFJ, INFJ, INTJ, ISTP, INFP, ISFP, INTP , ESTP, ESFP, ENFP, ENTP, ESTJ, ESFJ, ENFJ , or...development groups and the relationship between these differences and system success or failure. Chapter II will discuss some different theories of cognitive...reasoning termed analytic and hueristic. Analytic individuals reduce problems to a set of underlying relationships . These relationships , frequently

  17. Effect of stretching program in an industrial workplace on hamstring flexibility and sagittal spinal posture of adult women workers: a randomized controlled trial.

    Science.gov (United States)

    Muyor, José M; López-Miñarro, Pedro A; Casimiro, Antonio J

    2012-01-01

    To determine the effect of a stretching program performed in the workplace on the hamstring muscle extensibility and sagittal spinal posture of adult women. Fifty-eight adult women volunteers (mean age of 44.23 ± 8.87 years) from a private fruit and vegetable company were randomly assigned to experimental (n=27) or control (n=31) groups. The experimental group performed three exercises of hamstrings stretching of 20 seconds per exercise, three sessions a week for a period of 12 weeks. The control group did not participate in any hamstring stretching program. Hamstring flexibility was evaluated through the passive straight leg raise test and toe-touch test, performed both before and after the stretching program. Thoracic and lumbar curvatures and pelvic inclination were measured in relaxed standing and toe-touch test with a Spinal Mouse. Significant increases (p < 0.01) in toe-touch score and straight leg raise angle (in both legs) were found in the experimental group during post-test, while the control group showed a non-significant decrease for both toe-touch score and straight leg raise test. A significant decrease in thoracic curve and significant increase in pelvic inclination were found in the toe-touch test for the experimental group (p <0.05). However, no significant changes were found in standing posture for any group. Hamstring stretching exercises performed in the working place are effective for increasing hamstring muscle extensibility. This increase generates a more aligned thoracic curve and more anterior pelvic inclination when maximal trunk flexion is performed.

  18. Performance gaps in energy consumption : household groups and building characteristics

    NARCIS (Netherlands)

    van den Brom, P.I.; Meijer, A.; Visscher, H.J.

    2017-01-01

    The difference between actual and calculated energy is called the ‘energy-performance gap’. Possible explanations for this gap are construction mistakes, improper adjusting of equipment, excessive simplification in simulation models and occupant behaviour. Many researchers and governmental

  19. Chiropractic manipulative therapy of the thoracic spine in combination with stretch and strengthening exercises, in improving postural kyphosis in woman

    Directory of Open Access Journals (Sweden)

    Kim C. Branco

    2016-10-01

    Method: A randomised study design with thirty female participants between the ages of twenty and  thirty nine was selected. Group 1 (n = 10 received chiropractic spinal manipulative therapy to the thoracic spine. Group 2 (n = 10 received chiropractic spinal manipulative therapy to the thoracic spine as well as stretch and strengthening exercises i.e. stretching the pectoralis major muscles and strengthening the rhomboid, middle and inferior trapezius muscles. Group 3 (n = 10 received stretch and strengthening exercises. The stretch and strengthening exercises were performed in the consultation rooms to ensure that the participants were complying with the treatment and doing the exercises properly. The study consisted of seven consultations for Group 1 (they received treatment once a week for six weeks and for Groups 2 and 3 there were nineteen consultations (they received three treatments a week for six weeks. Objective data was recorded at the beginning of the first, fourth and seventh consultations for Group 1, and the first, tenth and nineteenth consultations for Groups 2 and 3. On the seventh consultation (for Group 1 and nineteenth consultation for Groups 2 and 3, only data collection was done. Objective data were obtained by using the Flexicurve® Ruler measurements for the angle of kyphosis. Visual analysis was done by taking lateral (sagittal view photographs at the beginning of the initial and final consultations. Results: Statistical analysis revealed significant statistical changes for the intragroup results for all three groups. No significant statistical difference was found between the groups for the inter-group analysis. Conclusion: The study showed that all three treatment protocols for Groups 1, 2, and 3 were effective. However, Group 1 had not shown a great improvement in their postural kyphosis, Group 3 had shown a relatively good improvement in their posture, while Group 2 had shown the best results with regards to improvement of the

  20. Interactive affective sharing versus non-interactive affective sharing in work groups : Comparative effects of group affect on work group performance and dynamics

    NARCIS (Netherlands)

    Klep, Annefloor; Wisse, Barbara; Van Der Flier, Henk

    This study explores whether the dynamic path to group affect, which is characterized by interactive affective sharing processes, yields different effects on task performance and group dynamics than the static path to group affect, which arises from non-interactive affective sharing. The results of

  1. Interactive affective sharing versus non-interactive affective sharing in work groups: Comparative effects of group affect on work group performance and dynamics

    NARCIS (Netherlands)

    Klep, A.H.M.; Wisse, B.M.; van der Flier, H.

    2011-01-01

    This study explores whether the dynamic path to group affect, which is characterized by interactive affective sharing processes, yields different effects on task performance and group dynamics than the static path to group affect, which arises from non-interactive affective sharing. The results of

  2. Task Performance in Small Group Settings: The Role of Group Members' Self-Efficacy And Collective Efficacy and Group's Characteristics

    Science.gov (United States)

    Khong, Jerrine Z. N.; Liem, Gregory Arief D.; Klassen, Robert M.

    2017-01-01

    The present study extends the literature by investigating the relative salience of self- and collective efficacy in predicting group performance among early adolescents in Indonesia. A total of 435 early adolescents (mean age 11.70 years, 53% female) were randomly assigned to groups of three to four and completed three group tasks (task 1:…

  3. Effect of Mechanical Stretching of the Skin on Collagen Fibril ...

    African Journals Online (AJOL)

    Stabilization of collagen fibres during development and through growth to maturation has now become fairly documented. In vitro effect of mechanical stretching of ratsf skin on oxidative deamination of ε-NH2-groups of lysine and hydroxylysine, and functional properties of its type . collagen were studied. Experiments were ...

  4. A Japanese Stretching Intervention Can Modify Lumbar Lordosis Curvature

    NARCIS (Netherlands)

    Kadono, Norio; Tsuchiya, Kazushi; Uematsu, Azusa; Kamoshita, Hiroshi; Kiryu, Kazunori; Hortobagyi, Tibor; Suzuki, Shuji

    Study Design: Eighteen healthy male adults were assigned to either an intervention or control group. Objectives: Isogai dynamic therapy (IDT) is one of Japanese stretching interventions and has been practiced for over 70 years. However, its scientific quantitative evidence remains unestablished. The

  5. OH stretching frequencies in systems with intramolecular hydrogen bonds

    DEFF Research Database (Denmark)

    Spanget-Larsen, Jens; Hansen, Bjarke Knud Vilster; Hansen, Poul Erik

    2011-01-01

    OH stretching wavenumbers were investigated for 30 species with intramolecularly hydrogen bonded hydroxyl groups, covering the range from 3600 to ca. 1900 cm-1. Theoretical wavenumbers were predicted with B3LYP/6-31G(d) density functional theory using the standard harmonic approximation, as well...

  6. Stretch-sensitive paresis and effort perception in hemiparesis.

    Science.gov (United States)

    Vinti, Maria; Bayle, Nicolas; Hutin, Emilie; Burke, David; Gracies, Jean-Michel

    2015-08-01

    In spastic paresis, stretch applied to the antagonist increases its inappropriate recruitment during agonist command (spastic co-contraction). It is unknown whether antagonist stretch: (1) also affects agonist recruitment; (2) alters effort perception. We quantified voluntary activation of ankle dorsiflexors, effort perception, and plantar flexor co-contraction during graded dorsiflexion efforts at two gastrocnemius lengths. Eighteen healthy (age 41 ± 13) and 18 hemiparetic (age 54 ± 12) subjects performed light, medium and maximal isometric dorsiflexion efforts with the knee flexed or extended. We determined dorsiflexor torque, Root Mean Square EMG and Agonist Recruitment/Co-contraction Indices (ARI/CCI) from the 500 ms peak voluntary agonist recruitment in a 5-s maximal isometric effort in tibialis anterior, soleus and medial gastrocnemius. Subjects retrospectively reported effort perception on a 10-point visual analog scale. During gastrocnemius stretch in hemiparetic subjects, we observed: (1) a 25 ± 7 % reduction of tibialis anterior voluntary activation (maximum reduction 98 %; knee extended vs knee flexed; p = 0.007, ANOVA); (2) an increase in dorsiflexion effort perception (p = 0.03, ANCOVA). Such changes did not occur in healthy subjects. Effort perception depended on tibialis anterior recruitment only (βARI(TA) = 0.61, p hemiparesis, voluntary ability to recruit agonist motoneurones is impaired--sometimes abolished--by antagonist stretch, a phenomenon defined here as stretch-sensitive paresis. In addition, spastic co-contraction increases effort perception, an additional incentive to evaluate and treat this phenomenon.

  7. How Do Groups Work? Age Differences in Performance and the Social Outcomes of Peer Collaboration

    Science.gov (United States)

    Leman, Patrick J.

    2015-01-01

    Do children derive different benefits from group collaboration at different ages? In the present study, 183 children from two age groups (8.8 and 13.4 years) took part in a class quiz as members of a group, or individually. In some groups, cohesiveness was made salient by awarding prizes to the top performing groups. In other groups, prizes were…

  8. Biaxial stretching of film principles and applications

    CERN Document Server

    Demeuse, M T

    2011-01-01

    Biaxial (having two axes) stretching of film is used for a range of applications and is the primary manufacturing process by which products are produced for the food packaging industry. Biaxial stretching of film: principles and applications provides an overview of the manufacturing processes and range of applications for biaxially stretched films. Part one reviews the fundamental principles of biaxial stretching. After an introductory chapter which defines terms, chapters discuss equipment design and requirements, laboratory evaluations, biaxial film structures and typical industrial processes for the biaxial orientation of films. Additional topics include post production processing of biaxially stretched films, the stress-strain behaviour of poly(ethylene terephthalate) and academic investigations of biaxially stretched films. Part two investigates the applications of biaxial films including fresh cut produce, snack packaging and product labelling. A final chapter investigates potential future trends for bi...

  9. Growth Performance and Behaviour in Grouped Pigs Fed Fibrous Diet

    Directory of Open Access Journals (Sweden)

    A. G. Bakare

    2014-08-01

    Full Text Available The objective of the study was to investigate the effect of feeding fibrous diets on growth performance and occurrence of aggressive behaviours in growing pigs. Sixty healthy castrated pigs (initial body weight: 46.7±4.35 kg were used. A basal diet was diluted with maize cobs to two levels (0 and 160 g/kg dry matter. Behavioural activities were observed using video cameras for three weeks, 8 h/d starting at 0800 h. Pigs subjected to control diet gained more weight compared to pigs receiving fibrous diet in week 1 (0.47 vs 0.15 kg, respectively and 2 (1.37 vs 1.04, respectively (p<0.05. Average daily gain was not affected by treatment diet in the third week. Pigs on high fibrous spent more time eating, lying down, standing, walking and fighting (p<0.05 compared to pigs on control diet. Time spent eating increased as the weeks progressed whilst time spent lying down decreased. Time of day had an effect on time spent on different behavioural activities exhibited by all pigs on different treatment diet (p<0.05. Inactivity was greatest in 5th (1200 to 1300 h hour of the day for all the pigs on different dietary treatments. Skin lesions appeared the most on neck and shoulder region followed by chest, stomach and hind leg region, and finally head region (p<0.05. Pigs on high fibre diet had more skin lesions in all body regions compared to pigs on control diet (p<0.05. It can be concluded that the high fibrous diet with maize cobs did not affect growth performance and also did not reduce aggressive behaviours. Aggressive behaviours emanated out of frustration when queuing on the feeder. The findings of this study suggest that maize cobs can be included at a level of 160 g/kg in diets of pigs. However, to reduce the level of aggression more feeding space should be provided.

  10. DNA analysis by single molecule stretching in nanofluidic biochips

    DEFF Research Database (Denmark)

    Abad, E.; Juarros, A.; Retolaza, A.

    2011-01-01

    Imprint Lithography (NIL) technology combined with a conventional anodic bonding of the silicon base and Pyrex cover. Using this chip, we have performed single molecule imaging on a bench-top fluorescent microscope system. Lambda phage DNA was used as a model sample to characterize the chip. Single molecules of λ-DNA......Stretching single DNA molecules by confinement in nanofluidic channels has attracted a great interest during the last few years as a DNA analysis tool. We have designed and fabricated a sealed micro/nanofluidic device for DNA stretching applications, based on the use of the high throughput Nano...... stained with the fluorescent dye YOYO-1 were stretched in the nanochannel array and the experimental results were analysed to determine the extension factor of the DNA in the chip and the geometrical average of the nanochannel inner diameter. The determination of the extension ratio of the chip provides...

  11. Stretching of red blood cells at high strain rates

    Science.gov (United States)

    Mancuso, J. E.; Ristenpart, W. D.

    2017-10-01

    Most work on the mechanical behavior of red blood cells (RBCs) in flow has focused on simple shear flows. Relatively little work has examined RBC deformations in the physiologically important extensional flow that occurs at the entrance to a constriction. In particular, previous work suggests that RBCs rapidly stretch out and then retract upon entering the constriction, but to date no model predicts this behavior for the extremely high strain rates typically experienced there. In this Rapid Communication, we use high speed video to perform systematic measurements of the dynamic stretching behavior of RBCs as they enter a microfluidic constriction. We demonstrate that both the Kelvin-Voigt and Skalak viscoelastic models capture the observed stretching dynamics, up to strain rates as high as 2000 s-1. The results indicate that the effective elastic modulus of the RBC membrane at these strain rates is an order of magnitude larger than moduli measured by micropipette aspiration or other low strain rate techniques.

  12. Numerical and experimental investigation of stretch-flange forming

    International Nuclear Information System (INIS)

    Cinotti, N.; Shakeri, H.R.; Worswick, M.J.; Truttmann, S.; Finn, M.J.; Jain, M.; Lloyd, D.J.

    2000-01-01

    Simulations of stretch flange forming operations are undertaken using explicit dynamic finite element calculations incorporating anisotropic yield criteria. Simple circular stretch flanges utilizing a single circular punch to expand the cut-out were considered. Experiments were performed using 101mm diameter tooling on AA 5754 and AA 5182 aluminum alloy sheets, with varying cut-out and gauge size. Metallurgical aspects of the formability of these aluminum alloys and damage mechanisms were studied. Both optical and Scanning Electron Microscopy (SEM) were used to study ductile fracture behaviour in these materials during the forming operation. The limit strains obtained from the circular stretch flange formability experiments are compared to forming limit diagram (FLD) data from hemispherical dome specimens. (author)

  13. Porter's generic strategies, strategic groups and firm performance in the construction industry : a complementary test

    OpenAIRE

    Molina Azorín, José Francisco; Quer Ramón, Diego

    2003-01-01

    A central theme in the strategic groups literature is that there is a theoretical relationship between groups and firm performance. However, the empirical evidence is conflicting. The aim of this research is to study this linkage through two analysis. Thus, the analysis that has been traditionally used (performance differences between groups) is complemented with an analysis of performance differences within each group. In order to set up strategic groups, we carry out an analysis about the...

  14. Contact angles on stretched solids

    Science.gov (United States)

    Mensink, Liz; Snoeijer, Jacco

    2017-11-01

    The surface energy of solid interfaces plays a central role in wetting, as they dictate the liquid contact angle. Yet, it has been challenging to measure the solid surface energies independently, without making use of Young's law. Here we present Molecular Dynamics (MD) simulations by which we measure the surface properties for all interfaces, including the solids. We observe change in contact angles upon stretching the solid substrates, showing that the surface energy is actually strain dependent. This is clear evidence of the so-called Shuttleworth effect, making it necessary to distinguish surface energy from surface tension. We discuss how this effect gives rise to a new class of elasto-capillary phenomena. ERC Consolidator Grant No. 616918.

  15. Heterogeneity in business groups and the corporate diversification firm performance relationship.

    NARCIS (Netherlands)

    George, R.; Kabir, Mohammed Rezaul

    2012-01-01

    This article examines how heterogeneous features among business groups influence the corporate diversification–firm performance relationship. The study classifies heterogeneity along three dimensions: group size, group diversity, and share ownership. Using a sample of firms from India, the study

  16. [Job performance in work organizations: the effects of management by group goals and job interdependence].

    Science.gov (United States)

    Ikeda, Hiroshi; Furukawa, Hisataka

    2015-04-01

    cThis study examined the interactive effect of management by group goals and job interdependence on employee's activities in terms of task and contextual performance. A survey was conducted among 140 Japanese employees. Results indicated that management by group goals was related only to contextual performance. Job interdependence, however, had a direct effect on both task and contextual performance. Moreover, moderated regression analyses revealed that for work groups requiring higher interdependence among employees, management by group goals had a positive relation to contextual performance but not to task performance. When interdependence was not necessarily required, however, management by group goals had no relation to contextual performance and even negatively impacted task performance, respectively. These results show that management by group goals affects task and contextual performance, and that this effect is moderated by job interdependence. This provides a theoretical extension as well as a practical application to the setting and management of group goals.

  17. Duration Dependent Effect of Static Stretching on Quadriceps and Hamstring Muscle Force

    Directory of Open Access Journals (Sweden)

    Leyla Alizadeh Ebadi

    2018-03-01

    Full Text Available The aim of this study was to determine the acute effect of static stretching on hamstring and quadriceps muscles’ isokinetic strength when applied for various durations to elite athletes, to investigate the effect of different static stretching durations on isokinetic strength, and finally to determine the optimal stretching duration. Fifteen elite male athletes from two different sport branches (10 football and five basketball participated in this study. Experimental protocol was designed as 17 repetitive static stretching exercises for hamstring and quadriceps muscle groups according to the indicated experimental protocols; ((A 5 min jogging; (B 5 min jogging followed by 15 s static stretching; (C 5 min jogging followed by 30 s static stretching; (D 5 min jogging, followed by static stretching for 45 s. Immediately after each protocol, an isokinetic strength test consisting of five repetitions at 60°/s speed and 20 repetitions at 180°/s speed was recorded for the right leg by the Isomed 2000 device. Friedman variance analysis test was employed for data analysis. According to the analyzes, it was observed that 5 min jogging and 15 s stretching exercises increased the isokinetic strength, whereas 30 and 45 s stretching exercises caused a decrease.

  18. Comparison of immediate effects between two medical stretching techniques on Hamstrings flexibility.

    Science.gov (United States)

    Aye, Thanda; Kuramoto-Ahuja, Tsugumi; Han, Heonsoo; Maruyama, Hitoshi

    2017-09-01

    [Purpose] The aim of this study was to compare immediate effects between new medical stretching (NMS) and conventional medical stretching (CMS) techniques on Hamstrings flexibility. [Subjects and Methods] Thirteen healthy adult males, with finger floor distance (FFD) less than zero centimeter, without known musculoskeletal and neurological impairment in spine or lower extremities, were included. The subjects were randomly allocated to two groups. The subjects were instructed to perform NMS and CMS (hold for 30 seconds once, twice for each side of lower extremity) for both sides (total two minutes, only one session for one day). The interval between the two techniques was one week. FFD was measured with digital standing trunk flexion meter at the pre-intervention and post-intervention of both techniques. [Results] The mean values of FFD improved at the post-interventions of both techniques. The tests of within subject effects indicated that the main effect of treatment was not significant but the main effect of time was significant and the interaction of treatment and time was also significant. [Conclusion] The results of this study indicated that both medical stretching techniques were effective on Hamstrings flexibility immediately after the intervention and NMS technique was more effective on improving flexibility.

  19. Are we on the same page? The performance effects of congruence between supervisor and group trust.

    Science.gov (United States)

    Carter, Min Z; Mossholder, Kevin W

    2015-09-01

    Taking a multiple-stakeholder perspective, we examined the effects of supervisor-work group trust congruence on groups' task and contextual performance using a polynomial regression and response surface analytical framework. We expected motivation experienced by work groups to mediate the positive influence of trust congruence on performance. Although hypothesized congruence effects on performance were more strongly supported for affective rather than for cognitive trust, we found significant indirect effects on performance (via work group motivation) for both types of trust. We discuss the performance effects of trust congruence and incongruence between supervisors and work groups, as well as implications for practice and future research. (c) 2015 APA, all rights reserved).

  20. Shining lights and bad apples : The effect of goal setting on group performance

    NARCIS (Netherlands)

    Curseu, P.L.; Janssen, S.E.A.; Meeus, M.T.H.

    2014-01-01

    Management education programs increasingly use group work as a tool for developing teamwork knowledge and skills. A critical factor identified in prior research to influence group performance in student groups is goal-setting. We test in a sample of 37 groups the effect of group goal configurations

  1. Stretching and jamming of finite automata

    NARCIS (Netherlands)

    Beijer, de N.; Kourie, D.G.; Watson, B.W.; Cleophas, L.G.W.A.; Watson, B.W.

    2004-01-01

    In this paper we present two transformations on automata, called stretching and jamming. These transformations will, under certain conditions, reduce the size of the transition table, and under other conditions reduce the string processing time. Given a finite automaton, we can stretch it by

  2. How milk-fed dairy calves perform in stable versus dynamic groups

    DEFF Research Database (Denmark)

    Pedersen, Rikke Engelbrecht; Sørensen, Jan Tind; Skjøth, F

    2009-01-01

    The objective of the present field trial was to compare calf performance among pre-weaned calves in two different group housing systems, stable groups ("all in-all out") and dynamic groups (continuous introduction). Performance data was collected from 484 calves randomly assigned to the two syste....../days). The prevalence of both diarrhoea and respiratory disease were more than twice as high among calves in dynamic groups compared to calves in stable groups....

  3. Strategy as stretch and leverage.

    Science.gov (United States)

    Hamel, G; Prahalad, C K

    1993-01-01

    Global competition is not just product versus product or company versus company. It is mind-set versus mind-set. Driven to understand the dynamics of competition, we have learned a lot about what makes one company more successful than another. But to find the root of competitiveness--to understand why some companies create new forms of competitive advantage while others watch and follow--we must look at strategic mind-sets. For many managers, "being strategic" means pursuing opportunities that fit the company's resources. This approach is not wrong, Gary Hamel and C.K. Prahalad contend, but it obscures an approach in which "stretch" supplements fit and being strategic means creating a chasm between ambition and resources. Toyota, CNN, British Airways, Sony, and others all displaced competitors with stronger reputations and deeper pockets. Their secret? In each case, the winner had greater ambition than its well-endowed rivals. Winners also find less resource-intensive ways of achieving their ambitious goals. This is where leverage complements the strategic allocation of resources. Managers at competitive companies can get a bigger bang for their buck in five basic ways: by concentrating resources around strategic goals; by accumulating resources more efficiently; by complementing one kind of resource with another; by conserving resources whenever they can; and by recovering resources from the market-place as quickly as possible. As recent competitive battles have demonstrated, abundant resources can't guarantee continued industry leadership.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Effectiveness of passive stretching versus hold relax technique in flexibility of hamstring muscle

    Directory of Open Access Journals (Sweden)

    Gauri Shankar

    2010-10-01

    Full Text Available Aim: To compare the effectiveness of passive stretching and hold relax technique in the flexibility of hamstring muscle. Methods: A total of 80 normal healthy female subjects between age group 20-30 years referred to the department of physiotherapy, Sumandeep Vidyapeeth University, sampling method being convenient sampling. The subjects were randomly divided in two groups i.e. passive stretching group (n=40 and PNF group (n=40 and given passive stretching and proprioceptive neuromuscular facilitation technique respectively. Active knee extension range was measured before and after the intervention by goniometer. Results: t test showed a highly significant (p=0.000 increase in range of motion in PNF group. Conclusion: Proprioceptive neuromuscular facilitation technique is more effective in increasing hamstring flexibility than the passive stretching.

  5. Effectiveness of Manual Therapy and Stretching for Baseball Players With Shoulder Range of Motion Deficits.

    Science.gov (United States)

    Bailey, Lane B; Thigpen, Charles A; Hawkins, Richard J; Beattie, Paul F; Shanley, Ellen

    Baseball players displaying deficits in shoulder range of motion (ROM) are at increased risk of arm injury. Currently, there is a lack of consensus regarding the best available treatment options to restore shoulder ROM. Instrumented manual therapy with self-stretching will result in clinically significant deficit reductions when compared with self-stretching alone. Controlled laboratory study. Shoulder ROM and humeral torsion were assessed in 60 active baseball players (mean age, 19 ± 2 years) with ROM deficits (nondominant - dominant, ≥15°). Athletes were randomly assigned to receive a single treatment of instrumented manual therapy plus self-stretching (n = 30) or self-stretching only (n = 30). Deficits in internal rotation, horizontal adduction, and total arc of motion were compared between groups immediately before and after a single treatment session. Treatment effectiveness was determined by mean comparison data, and a number-needed-to-treat (NNT) analysis was used for assessing the presence of ROM risk factors. Prior to intervention, players displayed significant ( P < 0.001) dominant-sided deficits in internal rotation (-26°), total arc of motion (-18°), and horizontal adduction (-17°). After the intervention, both groups displayed significant improvements in ROM, with the instrumented manual therapy plus self-stretching group displaying greater increases in internal rotation (+5°, P = 0.010), total arc of motion (+6°, P = 0.010), and horizontal adduction (+7°, P = 0.004) compared with self-stretching alone. For horizontal adduction deficits, the added use of instrumented manual therapy with self-stretching decreased the NNT to 2.2 (95% CI, 2.1-2.4; P = 0.010). Instrumented manual therapy with self-stretching significantly reduces ROM risk factors in baseball players with motion deficits when compared with stretching alone. The added benefits of manual therapy may help to reduce ROM deficits in clinical scenarios where stretching alone is

  6. Mediators of Yoga and Stretching for Chronic Low Back Pain

    Directory of Open Access Journals (Sweden)

    Karen J. Sherman

    2013-01-01

    Full Text Available Although yoga is an effective treatment for chronic low back pain, little is known about the mechanisms responsible for its benefits. In a trial comparing yoga to intensive stretching and self-care, we explored whether physical (hours of back exercise/week, cognitive (fear avoidance, body awareness, and self-efficacy, affective (psychological distress, perceived stress, positive states of mind, and sleep, and physiological factors (cortisol, DHEA mediated the effects of yoga or stretching on back-related dysfunction (Roland-Morris Disability Scale (RDQ. For yoga, 36% of the effect on 12-week RDQ was mediated by increased self-efficacy, 18% by sleep disturbance, 9% by hours of back exercise, and 61% by the best combination of all possible mediators (6 mediators. For stretching, 23% of the effect was mediated by increased self-efficacy, 14% by days of back exercise, and 50% by the best combination of all possible mediators (7 mediators. In open-ended questions, ≥20% of participants noted the following treatment benefits: learning new exercises (both groups, relaxation, increased awareness, and the benefits of breathing (yoga, benefits of regular practice (stretching. Although both self-efficacy and hours of back exercise were the strongest mediators for each intervention, compared to self-care, qualitative data suggest that they may exert their benefits through partially distinct mechanisms.

  7. Stretched versus compressed exponential kinetics in α-helix folding

    International Nuclear Information System (INIS)

    Hamm, Peter; Helbing, Jan; Bredenbeck, Jens

    2006-01-01

    In a recent paper (J. Bredenbeck, J. Helbing, J.R. Kumita, G.A. Woolley, P. Hamm, α-helix formation in a photoswitchable peptide tracked from picoseconds to microseconds by time resolved IR spectroscopy, Proc. Natl. Acad. Sci USA 102 (2005) 2379), we have investigated the folding of a photo-switchable α-helix with a kinetics that could be fit by a stretched exponential function exp(-(t/τ) β ). The stretching factor β became smaller as the temperature was lowered, a result which has been interpreted in terms of activated diffusion on a rugged energy surface. In the present paper, we discuss under which conditions diffusion problems occur with stretched exponential kinetics (β 1). We show that diffusion problems do have a strong tendency to yield stretched exponential kinetics, yet, that there are conditions (strong perturbation from equilibrium, performing the experiment in the folding direction) under which compressed exponential kinetics would be expected instead. We discuss the kinetics on free energy surfaces predicted by simple initiation-propagation models (zipper models) of α-helix folding, as well as by folding funnel models. We show that our recent experiment has been performed under condition for which models with strong downhill driving force, such as the zipper model, would predict compressed, rather than stretched exponential kinetics, in disagreement with the experimental observation. We therefore propose that the free energy surface along a reaction coordinate that governs the folding kinetics must be relatively flat and has a shape similar to a 1D golf course. We discuss how this conclusion can be unified with the thermodynamically well established zipper model by introducing an additional kinetic reaction coordinate

  8. The effects of alignments: examining group faultlines, organizational cultures, and performance.

    Science.gov (United States)

    Bezrukova, Katerina; Thatcher, Sherry M B; Jehn, Karen A; Spell, Chester S

    2012-01-01

    By integrating literature on group faultlines, organizational cultures, and value congruence, this research presents a framework that explains how cultural alignment across organizational levels may influence the relationship between faultlines and performance. The hypotheses were tested using representatively sampled multisource qualitative and quantitative data on 138 teams from a Fortune 500 company. The present findings demonstrate that although informational faultlines were detrimental for group performance, the negative relationship between faultlines and performance was reversed when cultures with a strong emphasis on results were aligned, was lessened when cultures with a weak emphasis on results were aligned, and remained negative when cultures were misaligned with respect to their results orientation. These findings show the importance of recognizing alignments not only within groups (group faultlines) but also outside groups (cultural alignments between the group and departments) when considering their implications for group performance.

  9. Effects of Functional Training and Calf Stretching on Risk of Falls in Older People: A Pilot Study.

    Science.gov (United States)

    do Rosario, Jailton Thulher; da Fonseca Martins, Natalia Santos; Peixinho, Carolina Carneiro; Oliveira, Liliam Fernandes

    2017-04-01

    This study aimed to determine the effects of a functional training and ankle stretching program in triceps surae torque, passive stiffness index, and in the risk for fall indicators in older adults. Twenty women (73.4 ± 7.3 years) were allocated into an intervention or control group. The 12-week intervention consisted of functional training and calf stretching exercises performed twice a week. Measurements of peak passive and active torque, passive stiffness, maximum dorsiflexion angle, and indexes of risk for falls (Timed Up and Go, functional reach test, QuickScreen-test) were collected. There were no significant differences for all variables, except the maximum dorsiflexion angle, which increased in the intervention group from 33.78 ± 8.57° to 38.89 ± 7.52°. The exercise program was not sufficient to enhance performance on functional tests and decrease the risk for falls in older adults. The significant increase in the maximum dorsiflexion indicates a positive impact of stretching exercises.

  10. Work-group characteristics and performance in collectivistic and individualistic cultures.

    Science.gov (United States)

    Sosik, John J; Jung, Dong I

    2002-02-01

    The authors conducted a cross-cultural longitudinal investigation of the effects of culture (individualism-collectivism dichotomy) on group characteristics (functional heterogeneity, preference for teamwork, group potency, outcome expectation) and on performance of 83 work groups performing 2 decision-making tasks over a 15-week period. The individualists (U.S. students) reported higher levels of functional heterogeneity and group potency and attained higher levels of group performance than did the collectivists (Korean students). In addition, culture and time interacted to influence ratings of group potency and outcome expectation. The difference in ratings of group potency between individualists and collectivists increased over time. Outcome expectation was greater among the collectivists in Time 1 and among the individualists in Time 2. The authors discuss implications for future cross-cultural group research and international management.

  11. Investing in a Large Stretch Press

    Science.gov (United States)

    Choate, M.; Nealson, W.; Jay, G.; Buss, W.

    1986-01-01

    Press for forming large aluminum parts from plates provides substantial economies. Study assessed advantages and disadvantages of investing in large stretch-forming press, and also developed procurement specification for press.

  12. Foam topology. Bending versus stretching dominated architectures

    International Nuclear Information System (INIS)

    Deshpande, V.; Ashby, M.; Fleck, N.

    2000-01-01

    Cellular solids can deform by either the bending or stretching of the cell walls. While most cellular solids are bending-dominated, those that are stretching-dominated are much more weight-efficient for structural applications. In this study we have investigated the topological criteria that dictate the deformation mechanism of a cellular solid by analysing the rigidity (or otherwise) of pin-jointed frameworks comprising inextensional struts. We show that the minimum node connectivity for a special class of lattice structured materials to be stretching-dominated is 6 for 2D foams and 12 for 3D foams. Similarly, sandwich plates comprising of truss cores faced with planar trusses require a minimum node connectivity of 9 to undergo stretching-dominated deformation for all loading states. (author)

  13. Excluded Volume Effects in Gene Stretching

    OpenAIRE

    Lam, Pui-Man

    2002-01-01

    We investigate the effects excluded volume on the stretching of a single DNA in solution. We find that for small force F, the extension h is not linear in F but proportion to F^{\\chi}, with \\chi=(1-\

  14. Team Satisfaction and Student Group Performance: A Cross-Cultural Study

    Science.gov (United States)

    Zeitun, Rami M.; Abdulqader, Khalid Shams; Alshare, Khaled A.

    2013-01-01

    The authors examined the relationship between team satisfaction and students' performance in group projects in two universities, one from the United States and one from Qatar. The results showed that there is a significant positive correlation between team satisfaction and group performance only for the American students. Demographic factors such…

  15. An empirical assessment of high-performing medical groups: results from a national study.

    Science.gov (United States)

    Shortell, Stephen M; Schmittdiel, Julie; Wang, Margaret C; Li, Rui; Gillies, Robin R; Casalino, Lawrence P; Bodenheimer, Thomas; Rundall, Thomas G

    2005-08-01

    The performance of medical groups is receiving increased attention. Relatively little conceptual or empirical work exists that examines the various dimensions of medical group performance. Using a national database of 693 medical groups, this article develops a scorecard approach to assessing group performance and presents a theory-driven framework for differentiating between high-performing versus low-performing medical groups. The clinical quality of care, financial performance, and organizational learning capability of medical groups are assessed in relation to environmental forces, resource acquisition and resource deployment factors, and a quality-centered culture. Findings support the utility of the performance scorecard approach and identification of a number of key factors differentiating high-performing from low-performing groups including, in particular, the importance of a quality-centered culture and the requirement of outside reporting from third party organizations. The findings hold a number of important implications for policy and practice, and the framework presented provides a foundation for future research.

  16. Origin of the blue shift of the CH stretching band for 2-butoxyethanol in water.

    Science.gov (United States)

    Katsumoto, Yukiteru; Komatsu, Hiroyuki; Ohno, Keiichi

    2006-07-26

    The blue shift of the isolated CD stretching band of 2-butoxyethanol (C4E1), which is observed for the aqueous solution during the dilution process, has been investigated by infrared (IR) spectroscopy and quantum chemical calculations. Mono-deuterium-labeled C4E1's were employed to remove the severe overlapping among the CH stretching bands. The isolated CD stretching mode of the alpha-methylene in the butoxy group shows a large blue shift, while those of the beta-methylene and methyl groups are not largely shifted. The spectral simulation results for the C4E1/H2O complexes indicate that the large blue shift of the CD stretching band of the butoxy group arises mainly from the hydration of the ether oxygen atom.

  17. The Comparative Study of the Effect of Stabilization Exercise and Stretching-Strengthening Exercise on Balance Parameters in Forward Head Posture Patients

    Directory of Open Access Journals (Sweden)

    Solmaz Salehi

    2013-04-01

    Full Text Available Objective: Balance disturbance is one of the observed impairments in patient with forward head posture (FHP. The aim of this study was comparing the effect of stabilization and stretching-strengthening exercises on the improvement of balance in these patients. Materials & Methods: Thirty three females with FHP were randomized into three groups of stabilization training, stretching-strengthening and control. The degree of FHP was measured using plumb line and the crania-vertebral angle. Balance tests performed in three different standing conditions on a force platform. The subjects were evaluated after 6 weeks training and 1 month follow-up by repeated measure ANOVA and T-test through SPSS software. Results: Balance parameters in both stretching-strengthening and control groups showed no significant changes (P>0.05 while in the stabilization group, significant decrease in displacement and velocity of center of pressure were seen under conditions of double-leg, eyes-open, foam-surface and single-leg, eyes-closed, rigid-surface (P0.05. Conclusion: In the conditions of standing that visual and proprioception information from plantar region of foot is challenged, stabilization exercises lead to more balance improvement than stretching-strengthening exercises.

  18. Does group affiliation improve firm performance? The case of Chinese State-owned firms

    NARCIS (Netherlands)

    Yu, Huanjun; van Ees, H.; Lensink, B.W.

    2009-01-01

    This paper analyses the performance of state-owned business groups in China. Group affiliation can be important for economic policy evaluation since the Chinese government promotes the formation of business groups as a first step in the process of reforming state enterprises into modern

  19. Short Circuits or Superconductors? Effects of Group Composition on High-Achieving Students' Science Assessment Performance.

    Science.gov (United States)

    Webb, Noreen M.; Nemer, Kariane Mari; Zuniga, Stephen

    2002-01-01

    Studied the effects of group ability composition (homogeneous versus heterogeneous) on group processes and outcomes for high-ability students completing science assessments. Results for 83 high ability students show the quality of group functioning serves as the strongest predictor of high-ability students' performance and explained much of the…

  20. Academic Procrastination and the Performance of Graduate-Level Cooperative Groups in Research Methods Courses

    Science.gov (United States)

    Jiao, Qun G.; DaRos-Voseles, Denise A.; Collins, Kathleen M. T.; Onwuegbuzie, Anthony J.

    2011-01-01

    This study examined the extent to which academic procrastination predicted the performance of cooperative groups in graduate-level research methods courses. A total of 28 groups was examined (n = 83 students), ranging in size from 2 to 5 (M = 2.96, SD = 1.10). Multiple regression analyses revealed that neither within-group mean nor within-group…

  1. Static stretch versus Mulligan Concept – long-term effects in gymnast’s flexibility

    Directory of Open Access Journals (Sweden)

    Manuela Karloh

    2010-04-01

    Full Text Available Flexibility is one of the most important physical aspects in Rhythmic Gymnastics (RG. The purpose of the study was to compare long-term changes in flexibility of hip extension in athletes of RG in function of two techniques: the static stretch and Mulligan’s Long Leg Traction. Participated eight female athletes with an average age of 13,25±0,89 years old, divided into two groups. Group 1 performed Mulligan technique and Group 2 performed static stretch. Flexibility training lasts for six weeks. It was executed 2 times a week, and was composed by 2 repetitions of 30 seconds for each lower limb. Photogrammetry was used to assess the range of motion (ROM of hip extension. ROM was assessed before and after six weeks of training. Descriptive and inferential statistics were used to analyze the data. The increase of ROM was statistically significant in both lower limbs in Group 1, and in right lower limb (RLL in Group 2. After six weeks of training the increase of ROM in Group 1 was 6,25°± 2,75º in left lower limb (LLL and 5,25°± 2,63º in RLL, and the increase in Group 2 was 6,75º± 4,64º in LLL and 5,5º± 3,41º in RLL. Comparing the two executed techniques, in relation to the increase of ROM, there were no statistically significant differences. We conclude that after six weeks of training the two proposed techniques have showed increases in range of motion.

  2. Comparison of the effects of hamstring stretching using proprioceptive neuromuscular facilitation with prior application of cryotherapy or ultrasound therapy

    Science.gov (United States)

    Magalhães, Francisco Elezier Xavier; Junior, Arlindo Rodrigues de Mesquita; Meneses, Harnold’s Tyson de Sousa; Moreira dos Santos, Rayele Pricila; Rodrigues, Ezaine Costa; Gouveia, Samara Sousa Vasconcelos; Gouveia, Guilherme Pertinni de Morais; Orsini, Marco; Bastos, Victor Hugo do Vale; Machado, Dionis de Castro Dutra

    2015-01-01

    [Purpose] Stretching using proprioceptive neuromuscular facilitation involve physiological reflex mechanisms through submaximal contraction of agonists which activate Golgi organ, promoting the relaxation reflex. The aim of this study was to evaluate the effects of proprioceptive neuromuscular facilitation alone and with prior application of cryotherapy and thermotherapy on hamstring stretching. [Subjects and Methods] The sample comprised of 32 young subjects with hamstring retraction of the right limb. The subjects were randomly allocated to four groups: the control, flexibility PNF, flexibility PNF associated with cryotherapy, flexibility PNF in association with ultrasound therapy. [Results] After 12 stretching sessions, experimental groups showed significant improvements compared to the control group. Moreover, we did not find any significant differences among the experimental groups indicating PNF stretching alone elicits similar results to PNF stretching with prior administration of cryotherapy or thermotherapy. [Conclusion] PNF without other therapy may be a more practical and less expensive choice for clinical care. PMID:26157261

  3. Effects of acute static, ballistic, and PNF stretching exercise on the muscle and tendon tissue properties.

    Science.gov (United States)

    Konrad, A; Stafilidis, S; Tilp, M

    2017-10-01

    The purpose of this study was to investigate the influence of a single static, ballistic, or proprioceptive neuromuscular facilitation (PNF) stretching exercise on the various muscle-tendon parameters of the lower leg and to detect possible differences in the effects between the methods. Volunteers (n = 122) were randomly divided into static, ballistic, and PNF stretching groups and a control group. Before and after the 4 × 30 s stretching intervention, we determined the maximum dorsiflexion range of motion (RoM) with the corresponding fascicle length and pennation angle of the gastrocnemius medialis. Passive resistive torque (PRT) and maximum voluntary contraction (MVC) were measured with a dynamometer. Observation of muscle-tendon junction (MTJ) displacement with ultrasound allowed us to determine the length changes in the tendon and muscle, respectively, and hence to calculate stiffness. Although RoM increased (static: +4.3%, ballistic: +4.5%, PNF: +3.5%), PRT (static: -11.4%, ballistic: -11.5%, PNF: -13,7%), muscle stiffness (static: -13.1%, ballistic: -20.3%, PNF: -20.2%), and muscle-tendon stiffness (static: -11.3%, ballistic: -10.5%, PNF: -13.7%) decreased significantly in all the stretching groups. Only in the PNF stretching group, the pennation angle in the stretched position (-4.2%) and plantar flexor MVC (-4.6%) decreased significantly. Multivariate analysis showed no clinically relevant difference between the stretching groups. The increase in RoM and the decrease in PRT and muscle-tendon stiffness could be explained by more compliant muscle tissue following a single static, ballistic, or PNF stretching exercise. © 2017 The Authors Scandinavian Journal of Medicine & Science In Sports Published by John Wiley & Sons Ltd.

  4. Hydrogen-Bonding Network and OH Stretch Vibration of Cellulose: Comparison of Computational Modeling with Polarized IR and SFG Spectra.

    Science.gov (United States)

    Lee, Christopher M; Kubicki, James D; Fan, Bingxin; Zhong, Linghao; Jarvis, Michael C; Kim, Seong H

    2015-12-10

    Hydrogen bonds play critical roles in noncovalent directional interactions determining the crystal structure of cellulose. Although diffraction studies accurately determined the coordinates of carbon and oxygen atoms in crystalline cellulose, the structural information on hydrogen atoms involved in hydrogen-bonding is still elusive. This could be complemented by vibrational spectroscopy; but the assignment of the OH stretch peaks has been controversial. In this study, we performed calculations using density functional theory with dispersion corrections (DFT-D2) for the cellulose Iβ crystal lattices with the experimentally determined carbon and oxygen coordinates. DFT-D2 calculations revealed that the OH stretch vibrations of cellulose are highly coupled and delocalized through intra- and interchain hydrogen bonds involving all OH groups in the crystal. Additionally, molecular dynamics (MD) simulations of a single cellulose microfibril showed that the conformations of OH groups exposed at the microfibril surface are not well-defined. Comparison of the computation results with the experimentally determined IR dichroism of uniaxially aligned cellulose microfibrils and the peak positions of various cellulose crystals allowed unambiguous identification of OH stretch modes observed in the vibrational spectra of cellulose.

  5. Using technology-enhanced, cooperative, group-project learning for student comprehension and academic performance

    Science.gov (United States)

    Tlhoaele, Malefyane; Suhre, Cor; Hofman, Adriaan

    2016-05-01

    Cooperative learning may improve students' motivation, understanding of course concepts, and academic performance. This study therefore enhanced a cooperative, group-project learning technique with technology resources to determine whether doing so improved students' deep learning and performance. A sample of 118 engineering students, randomly divided into two groups, participated in this study and provided data through questionnaires issued before and after the experiment. The results, obtained through analyses of variance and structural equation modelling, reveal that technology-enhanced, cooperative, group-project learning improves students' comprehension and academic performance.

  6. FUZZY BASED CONTRAST STRETCHING FOR MEDICAL IMAGE ENHANCEMENT

    Directory of Open Access Journals (Sweden)

    T.C. Raja Kumar

    2011-07-01

    Full Text Available Contrast Stretching is an important part in medical image processing applications. Contrast is the difference between two adjacent pixels. Fuzzy statistical values are analyzed and better results are produced in the spatial domain of the input image. The histogram mapping produces the resultant image with less impulsive noise and smooth nature. The probabilities of gray values are generated and the fuzzy set is determined from the position of the input image pixel. The result indicates the good performance of the proposed fuzzy based stretching. The inverse transform of the real values are mapped with the input image to generate the fuzzy statistics. This approach gives a flexible image enhancement for medical images in the presence of noises.

  7. An economical analysis of stretch-out for Angra 1

    International Nuclear Information System (INIS)

    Sakai, M.; Mascarenhas, H.A.

    1990-01-01

    An economical assessment of Angra 1 fuel cycle stretch-out is performed by means of NUCOST 1.0, a PWR power cost calculation code. International basic costs and an interest rate of 10%a were utilized. During the natural part of the fuel cycle an hypothetical capacity factor of 70% and in the stretch-out part a decrease in Plant's thermal efficiency have also been taken into account. The neutronic data were generated by FASER, MULTIMEDIUM, MEDIUM and PINPOW code system, simulating Angra 1 in the CAOC (constant Axial-Offset Control) operation. Assumming no proplems in the Plant's strecth-out phase, an optimum extension pont of 1 MWd/kg would be attained, what affords an US$700,000 savings by cycle when fuel and operation and maintenance costs are considered. (author) [pt

  8. Stretched polygons in a lattice tube

    Energy Technology Data Exchange (ETDEWEB)

    Atapour, M [Department of Mathematics and Statistics, York University, Toronto, ON M3J 1P3 (Canada); Soteros, C E [Department of Mathematics and Statistics, University of Saskatchewan, Saskatoon, SK S7N 5E6 (Canada); Whittington, S G [Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6 (Canada)], E-mail: atapour@mathstat.yorku.ca, E-mail: soteros@math.usask.ca, E-mail: swhittin@chem.utoronto.ca

    2009-08-14

    We examine the topological entanglements of polygons confined to a lattice tube and under the influence of an external tensile force f. The existence of the limiting free energy for these so-called stretched polygons is proved and then, using transfer matrix arguments, a pattern theorem for stretched polygons is proved. Note that the tube constraint allows us to prove a pattern theorem for any arbitrary value of f, while without the tube constraint it has so far only been proved for large values of f. The stretched polygon pattern theorem is used first to show that the average span per edge of a randomly chosen n-edge stretched polygon approaches a positive value, non-decreasing in f, as n {yields} {infinity}. We then show that the knotting probability of an n-edge stretched polygon confined to a tube goes to one exponentially as n {yields} {infinity}. Thus as n {yields} {infinity} when polygons are influenced by a force f, no matter its strength or direction, topological entanglements, as defined by knotting, occur with high probability. (fast track communication)

  9. Stretched polygons in a lattice tube

    International Nuclear Information System (INIS)

    Atapour, M; Soteros, C E; Whittington, S G

    2009-01-01

    We examine the topological entanglements of polygons confined to a lattice tube and under the influence of an external tensile force f. The existence of the limiting free energy for these so-called stretched polygons is proved and then, using transfer matrix arguments, a pattern theorem for stretched polygons is proved. Note that the tube constraint allows us to prove a pattern theorem for any arbitrary value of f, while without the tube constraint it has so far only been proved for large values of f. The stretched polygon pattern theorem is used first to show that the average span per edge of a randomly chosen n-edge stretched polygon approaches a positive value, non-decreasing in f, as n → ∞. We then show that the knotting probability of an n-edge stretched polygon confined to a tube goes to one exponentially as n → ∞. Thus as n → ∞ when polygons are influenced by a force f, no matter its strength or direction, topological entanglements, as defined by knotting, occur with high probability. (fast track communication)

  10. Influence of the stretch wrapping process on the mechanical behavior of a stretch film

    Science.gov (United States)

    Klein, Daniel; Stommel, Markus; Zimmer, Johannes

    2018-05-01

    Lightweight construction is an ongoing task in packaging development. Consequently, the stability of packages during transport is gaining importance. This study contributes to the optimization of lightweight packaging concepts regarding their stability. A very widespread packaging concept is the distribution of goods on a pallet whereas a Polyethylene (PE) stretch film stabilizes the lightweight structure during the shipment. Usually, a stretch wrapping machine applies this stretch film to the pallet. The objective of this study is to support packaging development with a method that predicts the result of the wrapping process, based on the mechanical characterization of the stretch film. This result is not only defined by the amount of stretch film, its spatial distribution on the pallet and its internal stresses that result in a containment force. More accurate, this contribution also considers the influence of the deformation history of the stretch film during the wrapping process. By focusing on similarities of stretch wrappers rather than on differences, the influence of generalized process parameters on stretch film mechanics and thereby on pallet stability can be determined experimentally. For a practical use, the predictive method is accumulated in an analytic model of the wrapping process that can be verified experimentally. This paves the way for experimental and numerical approaches regarding the optimization of pallet stability.

  11. A study of extracellular matrix remodeling in aortic heart valves using a novel biaxial stretch bioreactor.

    Science.gov (United States)

    Lei, Ying; Masjedi, Shirin; Ferdous, Zannatul

    2017-11-01

    In aortic valves, biaxial cyclic stretch is known to modulate cell differentiation, extracellular matrix (ECM) synthesis and organization. We designed a novel bioreactor that can apply independent and precise stretch along radial and circumferential directions in a tissue culture environment. While this bioreactor can be used for either native or engineered tissues, this study determined matrix remodeling and strain distribution of aortic cusps after culturing under biaxial stretch for 14 days. The contents of collagen and glycosaminoglycans were determined using standard biochemical assays and compared with fresh controls. Strain fields in static cusps were more uniform than those in stretched cusps, which indicated degradation of the ECM fibers. The glycosaminoglycan content was significantly elevated in the static control as compared to fresh or stretched cusps, but no difference was observed in collagen content among the groups. The strain profile of freshly isolated fibrosa vs. ventricularis and left, right, and noncoronary cusps were also determined by Digital Image Correlation technique. Distinct strain patterns were observed under stretch on fibrosa and ventricularis sides and among the three cusps. This work highlights the critical role of the anisotropic ECM structure for proper functions of native aortic valves and the beneficial effects of biaxial stretch for maintenance of the native ECM structure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Effects of aerobic training combined with respiratory muscle stretching on the functional exercise capacity and thoracoabdominal kinematics in patients with COPD: a randomized and controlled trial

    Directory of Open Access Journals (Sweden)

    Wada JT

    2016-10-01

    Full Text Available Juliano T Wada,1 Erickson Borges-Santos,1 Desiderio Cano Porras,1 Denise M Paisani,1 Alberto Cukier,2 Adriana C Lunardi,1 Celso RF Carvalho1 1Department of Physical Therapy, 2Department of Cardiopneumology, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil Background: Patients with COPD present a major recruitment of the inspiratory muscles, predisposing to chest incoordination, increasing the degree of dyspnea and impairing their exercise capacity. Stretching techniques could decrease the respiratory muscle activity and improve their contractile capacity; however, the systemic effects of stretching remain unknown.Objective: The aim of this study was to evaluate the effects of aerobic training combined with respiratory muscle stretching on functional exercise capacity and thoracoabdominal kinematics in patients with COPD.Design: This study was a randomized and controlled trial.Participants: A total of 30 patients were allocated to a treatment group (TG or a control group (CG; n=15, each group.Intervention: The TG was engaged in respiratory muscle stretching and the CG in upper and lower limb muscle stretching. Both groups performed 24 sessions (twice a week, 12 weeks of aerobic training.Evaluations: Functional exercise capacity (6-minute walk test, thoracoabdominal kinematics (optoelectronic plethysmography, and respiratory muscle activity (surface electromyography were evaluated during exercise. Analysis of covariance was used to compare the groups at a significance level of 5%.Results: After the intervention, the TG showed improved abdominal (ABD contribution, compartmental volume, mobility, and functional exercise capacity with decreased dyspnea when compared with the CG (P<0.01. The TG also showed a decreased respiratory muscle effort required to obtain the same pulmonary volume compared to the CG (P<0.001.Conclusion: Our results suggest that aerobic training combined with respiratory muscle stretching increases the functional

  13. A Systematic Review on the Effect of Mechanical Stretch on Hypertrophic Scars after Burn Injuries

    Directory of Open Access Journals (Sweden)

    Yu-ting Zhang

    2017-06-01

    Conclusion: From extensive literature search, there was no strong evidence indicating the positive effect of mechanical stretch using stretching exercise, massage, or splinting on hypertrophic scars. A firm conclusion cannot be drawn for the discrepancy of outcome measures and varied effectiveness. Most of the included studies lacked objective evaluation or control group for comparison. Further high quality studies with larger sample size and using standardized measurements are needed.

  14. Small group gender ratios impact biology class performance and peer evaluations.

    Science.gov (United States)

    Sullivan, Lauren L; Ballen, Cissy J; Cotner, Sehoya

    2018-01-01

    Women are underrepresented in science, technology, engineering, and mathematics (STEM) disciplines. Evidence suggests the microclimate of the classroom is an important factor influencing female course grades and interest, which encourages retention of women in STEM fields. Here, we test whether the gender composition of small (8-9 person) learning groups impacts course performance, sense of social belonging, and intragroup peer evaluations of intellectual contributions. Across two undergraduate active learning courses in introductory biology, we manipulated the classroom microclimate by varying the gender ratios of learning groups, ranging from 0% female to 100% female. We found that as the percent of women in groups increased, so did overall course performance for all students, regardless of gender. Additionally, women assigned higher peer- evaluations in groups with more women than groups with less women. Our work demonstrates an added benefit of the retention of women in STEM: increased performance for all, and positive peer perceptions for women.

  15. Task complexity and task, goal, and reward interdependence in group performance management : A prescriptive model

    NARCIS (Netherlands)

    van Vijfeijken, H.; Kleingeld, A.; van Tuijl, H.; Algera, J.A.; Thierry, Hk.

    2002-01-01

    A prescriptive model on how to design effective combinations of goal setting and contingent rewards for group performance management is presented. The model incorporates the constructs task complexity, task interdependence, goal interdependence, and reward interdependence and specifies optimal fit

  16. Task complexity and task, goal, and reward interdependence in group performance : a prescriptive model

    NARCIS (Netherlands)

    Vijfeijken, van H.T.G.A.; Kleingeld, P.A.M.; Tuijl, van H.F.J.M.; Algera, J.A.; Thierry, H.

    2002-01-01

    A prescriptive model on how to design effective combinations of goal setting and contingent rewards for group performance management is presented. The model incorporates the constructs task complexity, task interdependence, goal interdependence, and reward interdependence and specifies optimal fit

  17. WAIS Performance in Unincarcerated Groups of MMPI-Defined Sociopaths and Normal Controls

    Science.gov (United States)

    Allain, Albert N.

    1974-01-01

    This investigation examines WAIS performance in groups of 32 sociopaths and 33 normal controls defined by Minnesota Multiphasic Personality Inventory criteria. Sociopaths and normal controls show no differences in overall level of intellectual functioning. (Author)

  18. ACUTE EFFECTS OF DIFFERENT STATIC STRETCHING PROTOCOLS ON PEAK TORQUE, CONVENTIONAL AND FUNCTIONAL HAMSTRINGS-TO-QUADRICEPS RATIOS IN ACTIVE WOMEN

    Directory of Open Access Journals (Sweden)

    Ghada M. ALQaslah

    2016-10-01

    Full Text Available Background: This study might have been directed to some degree because of clashing results in the past studies regarding the impacts for different SS protocols on muscle strength and possibility for injury. The objective of the study was to investigate the acute effects of different static stretching (SS durations (20, 30, and 60s on isokinetic concentric quadriceps (Q and hamstrings (H peak torque (PT, eccentric H PT and conventional and functional H:Q ratios under different stretching conditions and angular velocities (60°and180°/s in active women. Methods: Isokinetic tests were performed on 108 active women. A HUMAC system was used to measure unilateral concentric Q and H PT, and eccentric H PT at 60 and 180º/s at baseline and after a bout of H-only, Q-only, and combined H and Q muscles SS. The data were statistically treated using five separate three-way (time x conditions x velocity ANOVA. Results: There were no significant differences among groups at baseline (P > 0.05. Significant reductions of all outcome measures have been shown to occur after 30 and 60s of SS (P 0.05. Conclusion: Short-lasting stretching can be done before exercises that require strength. However, since 30s or 60s stretching protocols adversely affect the muscle strength, performance and lower H:Q ratios they are not recommended prior to activities demanding the production of high forces.

  19. Optofluidic time-stretch quantitative phase microscopy.

    Science.gov (United States)

    Guo, Baoshan; Lei, Cheng; Wu, Yi; Kobayashi, Hirofumi; Ito, Takuro; Yalikun, Yaxiaer; Lee, Sangwook; Isozaki, Akihiro; Li, Ming; Jiang, Yiyue; Yasumoto, Atsushi; Di Carlo, Dino; Tanaka, Yo; Yatomi, Yutaka; Ozeki, Yasuyuki; Goda, Keisuke

    2018-03-01

    Innovations in optical microscopy have opened new windows onto scientific research, industrial quality control, and medical practice over the last few decades. One of such innovations is optofluidic time-stretch quantitative phase microscopy - an emerging method for high-throughput quantitative phase imaging that builds on the interference between temporally stretched signal and reference pulses by using dispersive properties of light in both spatial and temporal domains in an interferometric configuration on a microfluidic platform. It achieves the continuous acquisition of both intensity and phase images with a high throughput of more than 10,000 particles or cells per second by overcoming speed limitations that exist in conventional quantitative phase imaging methods. Applications enabled by such capabilities are versatile and include characterization of cancer cells and microalgal cultures. In this paper, we review the principles and applications of optofluidic time-stretch quantitative phase microscopy and discuss its future perspective. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Summary of the stretching tectonics research

    International Nuclear Information System (INIS)

    Yu Dagan

    1994-01-01

    The rise of stretching tectonics is established on the basis of recent structural geology theory, the establishment of metamorphic nucleus complex structural model on one hand plays an important promoting art to the development of stretching structure, on the other hand, it needs constant supplement and perfection in practice. Metamorphic nucleus complex is the carrier of comparatively deep geological information in vertical section of the crust and has wide distribution in the era of south China. Evidently, it can be taken as the 'key' to understanding the deep and studying the basement, Strengthening the study will play the important promoting role to the deep prospecting. The study of stretching tectonics is not only limited within the range of structure and metamorphism, but combine with the studies of sedimentation, magmatism, metamorphism and mineralization, thus form a new field of tectonic geology of self-developing system

  1. Lattice stretching bistability and dynamic heterogeneity

    DEFF Research Database (Denmark)

    Christiansen, Peter Leth; Savin, A. V.; Zolotaryuk, A. V.

    2012-01-01

    A simple one-dimensional lattice model is suggested to describe the experimentally observed plateau in force-stretching diagrams for some macromolecules. This chain model involves the nearest-neighbor interaction of a Morse-like potential (required to have a saturation branch) and a harmonic second......-neighbor coupling. Under an external stretching applied to the chain ends, the intersite Morse-like potential results in the appearance of a double-well potential within each chain monomer, whereas the interaction between the second neighbors provides a homogeneous bistable (degenerate) ground state, at least...... stretched bonds with a double-well potential. This case allows us to explain the existence of a plateau in the force-extension diagram for DNA and α-helix protein. Finally, the soliton dynamics are studied in detail....

  2. Optofluidic time-stretch microscopy: recent advances

    Science.gov (United States)

    Lei, Cheng; Nitta, Nao; Ozeki, Yasuyuki; Goda, Keisuke

    2018-04-01

    Flow cytometry is an indispensable method for valuable applications in numerous fields such as immunology, pathology, pharmacology, molecular biology, and marine biology. Optofluidic time-stretch microscopy is superior to conventional flow cytometry methods for its capability to acquire high-quality images of single cells at a high-throughput exceeding 10,000 cells per second. This makes it possible to extract copious information from cellular images for accurate cell detection and analysis with the assistance of machine learning. Optofluidic time-stretch microscopy has proven its effectivity in various applications, including microalga-based biofuel production, evaluation of thrombotic disorders, as well as drug screening and discovery. In this review, we discuss the principles and recent advances of optofluidic time-stretch microscopy.

  3. [Effectiveness of a stretching program on anxiety levels of workers in a logistic platform: a randomized controlled study].

    Science.gov (United States)

    Montero-Marín, Jesús; Asún, Sonia; Estrada-Marcén, Nerea; Romero, Rosario; Asún, Roberto

    2013-01-01

    To study the influence of a short programme of stretching exercises on anxiety levels of workers in a Spanish logistic company. A controlled clinical trial was carried out by means of an inter-subject design of random homogeneous blocks. Participants were assigned to the experimental group (n=67), treated with a programme of stretching exercises of 10-minute duration after working hours for a period of 3 months, or to the untreated control group (n=67). The primary result variable was anxiety, and the secondary variables were burnout syndrome, quality of life and flexibility. An analysis of covariance (ANCOVA) by intention to treat was performed on each of the result variables by controlling the baseline scores, the age and the practice of introjective activities outside the program, with the size effect calculated by means of the partial eta-squared value (η(2)). The results of the ANCOVA showed a moderate effect of the stretching exercise programme on the levels of anxiety (η(2)=0,06; P=.004). Other effects found were substantial for flexibility (η(2)=0,13; P<.001); moderately high for bodily pain (η(2)=0,08; P=.001), and moderate for vitality (η(2)=0,05; P=.016); mental health (η(2)=0,05; P=.017); general health (η(2)=0,04; P=.028) and exhaustion (η(2)=0,04; P=.025). The implementation of a short programme of stretching exercises in the work place was effective for reducing levels of anxiety, bodily pain and exhaustion, and for raising levels of vitality, mental health, general health and flexibility. This type of intervention could be seen as a low-cost strategy for improving the well-being of workers. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  4. Peer groups and operational cycle enhancements to the performance indicator report

    International Nuclear Information System (INIS)

    Stromberg, H.M.; DeHaan, M.S.; Gentillon, C.D.; Wilson, G.E.; Vanden Heuvel, L.N.

    1992-01-01

    Accurate performance evaluation and plant trending by the performance indicator program are integral parts of monitoring the operation of commercial nuclear power plants. The presentations of the NRC/AEOD performance indicator program have undergone a number of enhancements. The diversity of the commercial nuclear plants, coupled with continued improvements in the performance indicator program, has resulted in the evaluation of plants in logical peer groups and highlighted the need to evaluate the impact of plant operational conditions on the performance indicators. These enhancements allow a more-meaningful evaluation of operating commercial nuclear power plant performance. This report proposes methods to enhance the presentation of the performance indicator data by analyzing the data in logical peer groups and displaying the performance indicator data based on the operational status of the plants. Previously, preliminary development of the operational cycle displays of the performance indicator data was documented. This report extends the earlier findings and presents the continued development of the peer groups and operational cycle trend and deviation data and displays. This report describes the peer groups and enhanced PI data presentations by considering the operational cycle phase breakdowns, calculation methods, and presentation methods

  5. Consensus group sessions are useful to reconcile stakeholders’ perspectives about network performance evaluation

    Directory of Open Access Journals (Sweden)

    Marie-Eve Lamontagne

    2010-12-01

    Full Text Available Background: Having a common vision among network stakeholders is an important ingredient to developing a performance evaluation process. Consensus methods may be a viable means to reconcile the perceptions of different stakeholders about the dimensions to include in a performance evaluation framework.Objectives: To determine whether individual organizations within traumatic brain injury (TBI networks differ in perceptions about the importance of performance dimensions for the evaluation of TBI networks and to explore the extent to which group consensus sessions could reconcile these perceptions.Methods: We used TRIAGE, a consensus technique that combines an individual and a group data collection phase to explore the perceptions of network stakeholders and to reach a consensus within structured group discussions.Results: One hundred and thirty-nine professionals from 43 organizations within eight TBI networks participated in the individual data collection; 62 professionals from these same organisations contributed to the group data collection. The extent of consensus based on questionnaire results (e.g. individual data collection was low, however, 100% agreement was obtained for each network during the consensus group sessions. The median importance scores and mean ranks attributed to the dimensions by individuals compared to groups did not differ greatly. Group discussions were found useful in understanding the reasons motivating the scoring, for resolving differences among participants, and for harmonizing their values.Conclusion: Group discussions, as part of a consensus technique, appear to be a useful process to reconcile diverging perceptions of network performance among stakeholders.

  6. Effect of "group spell" upon Shotokan black-belt performance of Heian kata.

    Science.gov (United States)

    Layton, C; Moran, P

    1999-10-01

    11 experienced black-belt subjects were individually timed on each of the five Heian kata and then timed again when performing as part of a group. The pull of the group had a significant effect upon timing on two of the kata.

  7. Ethnic and Gender Diversity, Process and Performance in Groups of Business Students in Sweden

    Science.gov (United States)

    Umans, Timurs; Collin, Sven-Olof; Tagesson, Torbjorn

    2008-01-01

    This article investigates the complex interrelation between ethnic and gender diversity, process and performance among groups of business students. The article is based on an empirical survey of business students working on a complex assignment in groups of two to five in a small Swedish university. The results indicate that gender diversity leads…

  8. Performance differentials of agglomeration and strategic groups: a test of incubation and new venture strategy

    NARCIS (Netherlands)

    Amezcua, A.S.; Ratinho, Tiago; Jayamohan, P.

    2013-01-01

    Our paper investigates how nascent firms ‘performance is affected by strategic group membership and industrial agglomeration. Agglomeration is defined using geographical concentration while strategic groups are measured as incubated firms that belong to the industry most highly represented within an

  9. Periostin inhibits mechanical stretch-induced apoptosis in osteoblast-like MG-63 cells.

    Science.gov (United States)

    Yu, Kai-Wen; Yao, Chung-Chen; Jeng, Jiiang-Huei; Shieh, Hao-Ying; Chen, Yi-Jane

    2018-04-01

    Appropriate mechanical stress plays an important role in regulating the proliferation and differentiation of osteoblasts, whereas high-level mechanical stress may be harmful and compromise cell survival. Periostin, a matricellular protein, is essential in maintaining functional integrity of bone and collagen-rich connective tissue in response to mechanical stress. This study investigated whether or not high-level mechanical stretch induces cell apoptosis and the regulatory role of periostin in mechanical stretch-induced apoptosis in osteoblastic cells. Osteoblast-like MG-63 cells were seeded onto Bio-Flex I culture plates and subjected to cyclic mechanical stretching (15% elongation, 0.1 Hz) in a Flexercell tension plus system-5000. The same process was applied to cells pre-treated with exogenous human recombinant periostin before mechanical stretching. We used a chromatin condensation and membrane permeability dead cell apoptosis kit to evaluate the stretch-induced cell responses. Expression of caspase-3 and cPARP was examined by immunofluorescent stain and flow cytometry. The expression of periostin in MG-63 cells is involved in the TGF-β signaling pathway. High-level cyclic mechanical stretch induced apoptotic responses in MG-63 osteoblastic cells. The percentages of apoptotic cells and cells expressing cPARP protein increased in the groups of cells subjected to mechanical stretch, but these responses were absent in the presence of exogenous periostin. Our study revealed that high-level mechanical stretch induces apoptotic cell death, and that periostin plays a protective role against mechanical stretch-induced apoptosis in osteoblastic cells. Copyright © 2017. Published by Elsevier B.V.

  10. Stretching and folding mechanism in foams

    International Nuclear Information System (INIS)

    Tufaile, Alberto; Pedrosa Biscaia Tufaile, Adriana

    2008-01-01

    We have described the stretching and folding of foams in a vertical Hele-Shaw cell containing air and a surfactant solution, from a sequence of upside-down flips. Besides the fractal dimension of the foam, we have observed the logistic growth for the soap film length. The stretching and folding mechanism is present during the foam formation, and this mechanism is observed even after the foam has reached its respective maximum fractal dimension. Observing the motion of bubbles inside the foam, large bubbles present power spectrum associated with random walk motion in both directions, while the small bubbles are scattered like balls in a Galton board

  11. Filament stretching rheometer: inertia compensation revisited

    DEFF Research Database (Denmark)

    Szabo, Peter; McKinley, Gareth H.

    2003-01-01

    The necessary inertia compensation used in the force balance for the filament stretching rheometer is derived for an arbitrary frame of reference. This enables the force balance to be used to extract correctly the extensional viscosity from measurements of the tensile force at either end of the e......The necessary inertia compensation used in the force balance for the filament stretching rheometer is derived for an arbitrary frame of reference. This enables the force balance to be used to extract correctly the extensional viscosity from measurements of the tensile force at either end...

  12. Stretching and folding mechanism in foams

    Energy Technology Data Exchange (ETDEWEB)

    Tufaile, Alberto [Escola de Artes, Ciencias e Humanidades, Soft Matter Laboratory, Universidade de Sao Paulo, 03828-000 Sao Paulo, SP (Brazil)], E-mail: tufaile@usp.br; Pedrosa Biscaia Tufaile, Adriana [Escola de Artes, Ciencias e Humanidades, Soft Matter Laboratory, Universidade de Sao Paulo, 03828-000 Sao Paulo, SP (Brazil)

    2008-10-13

    We have described the stretching and folding of foams in a vertical Hele-Shaw cell containing air and a surfactant solution, from a sequence of upside-down flips. Besides the fractal dimension of the foam, we have observed the logistic growth for the soap film length. The stretching and folding mechanism is present during the foam formation, and this mechanism is observed even after the foam has reached its respective maximum fractal dimension. Observing the motion of bubbles inside the foam, large bubbles present power spectrum associated with random walk motion in both directions, while the small bubbles are scattered like balls in a Galton board.

  13. Intravoxel water diffusion heterogeneity MR imaging of nasopharyngeal carcinoma using stretched exponential diffusion model

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Vincent; Khong, Pek Lan [University of Hong Kong, Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, Queen Mary Hospital, Pok Fu Lam (China); Lee, Victor Ho Fun; Lam, Ka On; Sze, Henry Chun Kin [University of Hong Kong, Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, Queen Mary Hospital, Pok Fu Lam (China); Chan, Queenie [Philips Healthcare, Hong Kong, Shatin, New Territories (China)

    2015-06-01

    To determine the utility of stretched exponential diffusion model in characterisation of the water diffusion heterogeneity in different tumour stages of nasopharyngeal carcinoma (NPC). Fifty patients with newly diagnosed NPC were prospectively recruited. Diffusion-weighted MR imaging was performed using five b values (0-2,500 s/mm{sup 2}). Respective stretched exponential parameters (DDC, distributed diffusion coefficient; and alpha (α), water heterogeneity) were calculated. Patients were stratified into low and high tumour stage groups based on the American Joint Committee on Cancer (AJCC) staging for determination of the predictive powers of DDC and α using t test and ROC curve analyses. The mean ± standard deviation values were DDC = 0.692 ± 0.199 (x 10{sup -3} mm{sup 2}/s) for low stage group vs 0.794 ± 0.253 (x 10{sup -3} mm{sup 2}/s) for high stage group; α = 0.792 ± 0.145 for low stage group vs 0.698 ± 0.155 for high stage group. α was significantly lower in the high stage group while DDC was negatively correlated. DDC and α were both reliable independent predictors (p < 0.001), with α being more powerful. Optimal cut-off values were (sensitivity, specificity, positive likelihood ratio, negative likelihood ratio) DDC = 0.692 x 10{sup -3} mm{sup 2}/s (94.4 %, 64.3 %, 2.64, 0.09), α = 0.720 (72.2 %, 100 %, -, 0.28). The heterogeneity index α is robust and can potentially help in staging and grading prediction in NPC. (orig.)

  14. Intravoxel water diffusion heterogeneity MR imaging of nasopharyngeal carcinoma using stretched exponential diffusion model

    International Nuclear Information System (INIS)

    Lai, Vincent; Khong, Pek Lan; Lee, Victor Ho Fun; Lam, Ka On; Sze, Henry Chun Kin; Chan, Queenie

    2015-01-01

    To determine the utility of stretched exponential diffusion model in characterisation of the water diffusion heterogeneity in different tumour stages of nasopharyngeal carcinoma (NPC). Fifty patients with newly diagnosed NPC were prospectively recruited. Diffusion-weighted MR imaging was performed using five b values (0-2,500 s/mm 2 ). Respective stretched exponential parameters (DDC, distributed diffusion coefficient; and alpha (α), water heterogeneity) were calculated. Patients were stratified into low and high tumour stage groups based on the American Joint Committee on Cancer (AJCC) staging for determination of the predictive powers of DDC and α using t test and ROC curve analyses. The mean ± standard deviation values were DDC = 0.692 ± 0.199 (x 10 -3 mm 2 /s) for low stage group vs 0.794 ± 0.253 (x 10 -3 mm 2 /s) for high stage group; α = 0.792 ± 0.145 for low stage group vs 0.698 ± 0.155 for high stage group. α was significantly lower in the high stage group while DDC was negatively correlated. DDC and α were both reliable independent predictors (p < 0.001), with α being more powerful. Optimal cut-off values were (sensitivity, specificity, positive likelihood ratio, negative likelihood ratio) DDC = 0.692 x 10 -3 mm 2 /s (94.4 %, 64.3 %, 2.64, 0.09), α = 0.720 (72.2 %, 100 %, -, 0.28). The heterogeneity index α is robust and can potentially help in staging and grading prediction in NPC. (orig.)

  15. Two ways related to performance in elite sport: the path of self-confidence and competitive anxiety and the path of group cohesion and group goal-clarity.

    Science.gov (United States)

    Kjørmo, Odd; Halvari, Hallgeir

    2002-06-01

    A model tested among 136 Norwegian Olympic-level athletes yielded two paths related to performance. The first path indicated that self-confidence, modeled as an antecedent of competitive anxiety, is negatively correlated with anxiety. Competitive anxiety in turn is negatively correlated with performance. The second path indicated that group cohesion is positively correlated with group goal-clarity, which in turn is positively correlated with performance. Competitive anxiety mediates the relation between self-confidence and performance, whereas group goal-clarity mediates the relation between group cohesion and performance. Results from multiple regression analyses supported the model in the total sample and among individual sport athletes organized in training groups (n = 100). Among team sport athletes (n = 36), personality and group measures are more strongly intercorrelated than among individual sport athletes, and the relation with performance is more complex for the former group. The interaction of self-confidence and competitive anxiety is related to performance among team sport athletes.

  16. Performance-influencing factors in homogeneous groups of top athletes: a cross-sectional study

    NARCIS (Netherlands)

    van Ingen Schenau, G.J.; Bakker, F.C.; de Koning, J.J.; de Groot, G.

    1996-01-01

    Sport scientists have identified many factors as prerequisites for a good athletic performance in various sports. It is not clear whether these factors also influence the best performers in the homogeneous groups of top athletes selected for national teams. In this study, this issue is addressed

  17. Using Technology-Enhanced, Cooperative, Group-Project Learning for Student Comprehension and Academic Performance

    Science.gov (United States)

    Tlhoaele, Malefyane; Suhre, Cor; Hofman, Adriaan

    2016-01-01

    Cooperative learning may improve students' motivation, understanding of course concepts, and academic performance. This study therefore enhanced a cooperative, group-project learning technique with technology resources to determine whether doing so improved students' deep learning and performance. A sample of 118 engineering students, randomly…

  18. The influence of group discussion on performance judgments: rating accuracy, contrast effects, and halo.

    Science.gov (United States)

    Palmer, Jerry K; Loveland, James M

    2008-03-01

    The authors investigated the effect of group discussion, such as may occur formally in panel interview scenarios, assessment centers, or 360-degree feedback situations, on judgments of performance. Research on group polarization suggests that the effect of group discussion combined with raters' preexisting impressions of ratees or interviewees should result in an extremitization of impressions. Thus, the authors hypothesized that group discussion would (a) make ratings less accurate, (b) polarize impressions that were already good or poor as reflected by greater contrast effects, and (c) increase positive halo. Results indicated that group discussion resulted in less accurate ratings and greater contrast effects. Additional analyses suggested that group discussion increased positive halo. The authors discuss implications for research on group or panel judgments.

  19. Fibril orientation redistribution induced by stretching of cellulose nanofibril hydrogels

    International Nuclear Information System (INIS)

    Josefsson, Gabriella; Gamstedt, E. Kristofer; Ahvenainen, Patrik; Mushi, Ngesa Ezekiel

    2015-01-01

    The mechanical performance of materials reinforced by cellulose nanofibrils is highly affected by the orientation of these fibrils. This paper investigates the nanofibril orientation distribution of films of partly oriented cellulose nanofibrils. Stripes of hydrogel films were subjected to different amount of strain and, after drying, examined with X-ray diffraction to obtain the orientation of the nanofibrils in the films, caused by the stretching. The cellulose nanofibrils had initially a random in-plane orientation in the hydrogel films and the strain was applied to the films before the nanofibrils bond tightly together, which occurs during drying. The stretching resulted in a reorientation of the nanofibrils in the films, with monotonically increasing orientation towards the load direction with increasing strain. Estimation of nanofibril reorientation by X-ray diffraction enables quantitative comparison of the stretch-induced orientation ability of different cellulose nanofibril systems. The reorientation of nanofibrils as a consequence of an applied strain is also predicted by a geometrical model of deformation of nanofibril hydrogels. Conversely, in high-strain cold-drawing of wet cellulose nanofibril materials, the enhanced orientation is promoted by slipping of the effectively stiff fibrils

  20. Seating Arrangement, Group Composition and Competition-driven Interaction: Effects on Students' Performance in Physics

    International Nuclear Information System (INIS)

    Roxas, R. M.; Monterola, C.; Carreon-Monterola, S. L.

    2010-01-01

    We probe the effect of seating arrangement, group composition and group-based competition on students' performance in Physics using a teaching technique adopted from Mazur's peer instruction method. Ninety eight lectures, involving 2339 students, were conducted across nine learning institutions from February 2006 to June 2009. All the lectures were interspersed with student interaction opportunities (SIO), in which students work in groups to discuss and answer concept tests. Two individual assessments were administered before and after the SIO. The ratio of the post-assessment score to the pre-assessment score and the Hake factor were calculated to establish the improvement in student performance. Using actual assessment results and neural network (NN) modeling, an optimal seating arrangement for a class was determined based on student seating location. The NN model also provided a quantifiable method for sectioning students. Lastly, the study revealed that competition-driven interactions increase within-group cooperation and lead to higher improvement on the students' performance.

  1. Effect of Kinesiotaping and Stretching Exercise on Forward Shoulder Angle in Females with Rounded Shoulder Posture

    Directory of Open Access Journals (Sweden)

    Arghavan Hajibashi

    2014-12-01

    Full Text Available Background: Rounded shoulder posture is a common abnormal posture in upper quarter. Kinesiotape is a new intervention that recently used in rehabilitation. There are no studies have examined the effect of kinesiotape on rounded shoulder posture. Therefore the purpose of this study was to determine the effect of scapular kinesiotaping and pectoralis minor stretching exercise on forward shoulder angle in female subjects with rounded shoulder posture. Methods: Twenty female students aged between 18 to 25 years old with rounded shoulder posture participated in this study. Then, the subjects were randomly and equally assigned to two groups: the stretch group and the stretch plus kinesiotape group. Both groups were trained for doing home exercise to stretch Pectoralis minor bilaterally for two weeks. Kinesiotape group received kinesiotape on scapular area additionally. Forward shoulder angle was measured in four sessions including pre-intervention (first session, immediately after the first intervention (second session, fourth day (third session and at the end of two weeks (fourth session. Two-way repeated measures ANOVA (4×2 was used for data analysis. Results: kinesiotape group showed significant within-group decrease in forward shoulder angle between first session with three other sessions (P≤0.05.There was no significant within-group difference in stretch group and between groups (P=0.20 forward shoulder angle-by-group interaction in measurement sessions was significantly different (P=0.02 Conclusion: scapular kinesiotaping along with pectoralis minor stretching exercise improved rounded shoulder posture in subjects of the present study. kinesiotape is suggested as a complem

  2. A culture of education: Enhancing school performance of youth living in residential group care in Ontario.

    Science.gov (United States)

    Gharabaghi, Kiaras

    2011-01-01

    This article presents a synthesis of what is known about the educational experiences of youth living in residential group care based on a literature review that highlights both the experiences of the youth themselves and the operational context of residential group care in Ontario as it pertains to educational performance. The author argues that there is little emphasis on education within the residential group care sector in Ontario that could translate into more productive educational experiences for youth. The article then provides a framework for developing a culture of education for residential group care that can be acted upon expeditiously. Enhancing the educational performance of young people living in group care will require a cultural approach that provides for daily and pervasive education supports and encouragement, and aims to enhance the lived experience of young people pursuant to their education.

  3. Effect of Age Group on Technical-Tactical Performance Profile of the Serve in Men's Volleyball.

    Science.gov (United States)

    García-de-Alcaraz, Antonio; Ortega, Enrique; Palao, José M

    2016-10-01

    The aim of this study was to analyze the technical-tactical performance profile of the serve for various age groups and categories of competition in men's volleyball. The sample comprised 13,262 serves performed by 986 players in 299 sets observed in various categories of competition (U-14, U-16, U-19, national senior, and international senior). An observational design was used. The variables studied were category of competition, type of execution, and serve performance. The results showed that for higher age groups (senior categories), there were significantly fewer jump serves and poorer serve performance, regardless of players' maturity and training development. The use of the jump serves increased the serve risk while attempting to hinder the organization of the opponent attack. This paper discusses the serve evolution and the implications on the training process at the different age groups in men's volleyball. © The Author(s) 2016.

  4. Transcultural group performance in extreme environment: Issues, concepts and emerging theory

    Science.gov (United States)

    Lapierre, Judith; Bouchard, Stéphane; Martin, Thibault; Perreault, Michel

    2009-06-01

    A simulation for flight of international crew on space station took place in Moscow from July 1999 to April 2000 (SFINCS) at the State Biomedical Institute of Russia (IBMP) isolation chambers. Objectives of this study were to identify concepts of psychosocial adaptation and of social interactions to develop an explanation of the transcultural group performance. Method: constructivist epistemology with grounded theory research and fourth generation evaluation were used. Data on processes and interactions were gathered during 110 days of confinement as a subject and extended to 240 days as an outside scientist. Results indicate that coping is influenced by usual coping strategies and coping behaviors inside. Several stresses and human factor issues were identified altering well being and performance inside the chambers. Enabling and limiting forces are discussed. A theory on transcultural group performance is proposed. Issues are raised that appear critical to selection, training and group performance.

  5. Performance Anxiety at English PBL Groups Among Taiwanese Medical Students: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Cheng-Sheng Chen

    2008-03-01

    Full Text Available Students' performance anxiety can impact negatively on the effectiveness of medical education reform, including performance in problem-based learning (PBL and in using English in discussion. This study aimed to investigate the nature of performance anxiety among Taiwanese medical students in an English-language PBL group. Eighteen Taiwanese, one American and four Asian medical students who were attending an international PBL workshop were enrolled. A questionnaire seeking demographic data and experience in use of PBL and eight questions evaluating performance anxiety were administered. The performance anxiety of Taiwanese medical students was compared to that of the Asians and the one American. Frequencies of each performance anxiety were calculated. The results suggested that the Taiwanese students showed more anxiety than the one student from the United States, but less than other Asian students. The acts of giving a report, being the center of attention, and talking in the PBL group were the most common situations related to anxiety in PBL groups. Using English and working in a new PBL environment are possible sources of anxiety. The presence of anxiety among the Taiwanese medical students in English PBL groups implies the necessity for developing an effective strategy to deal with students' performance anxiety.

  6. Group social rank is associated with performance on a spatial learning task.

    Science.gov (United States)

    Langley, Ellis J G; van Horik, Jayden O; Whiteside, Mark A; Madden, Joah R

    2018-02-01

    Dominant individuals differ from subordinates in their performances on cognitive tasks across a suite of taxa. Previous studies often only consider dyadic relationships, rather than the more ecologically relevant social hierarchies or networks, hence failing to account for how dyadic relationships may be adjusted within larger social groups. We used a novel statistical method: randomized Elo-ratings, to infer the social hierarchy of 18 male pheasants, Phasianus colchicus , while in a captive, mixed-sex group with a linear hierarchy. We assayed individual learning performance of these males on a binary spatial discrimination task to investigate whether inter-individual variation in performance is associated with group social rank. Task performance improved with increasing trial number and was positively related to social rank, with higher ranking males showing greater levels of success. Motivation to participate in the task was not related to social rank or task performance, thus indicating that these rank-related differences are not a consequence of differences in motivation to complete the task. Our results provide important information about how variation in cognitive performance relates to an individual's social rank within a group. Whether the social environment causes differences in learning performance or instead, inherent differences in learning ability predetermine rank remains to be tested.

  7. Stretching the frontiers of precaution

    Directory of Open Access Journals (Sweden)

    Derek Osborn

    2002-09-01

    Full Text Available The increasing pace and impact of technological change in the world underline the growing need for taking due precautions. In this essay the author reviews a number of cases over the past 2 centuries where new technologies have been introduced too rapidly with too little attention to possible consequences and avoidable damage to health or the environment has been caused. The author goes on to discuss the precautionary approach to new technology, and urges more widespread use of it. He underlines the importance of 4 key points: (1 technology must not be demonised as the enemy - wise use of technology and technological solutions are themselves part of a precautionary approach; (2 a concern for social and environmental justice must be part of a broad precautionary approach - innovations which may potentially benefit one group while putting other groups at risk are very problematic; (3 we must safeguard the public realm and its ability to weigh up proposed innovations and new processes dispassionately - the privatisation of regulation and management of safeguards is very dangerous; (4 innovation and the management of precautionary safeguards are too important to be left to experts or governments alone - there must be sufficient public understanding and support for the introduction of new technologies with all the risks they may involve if public confidence is not to be eroded and greater restrictions imposed. The precautionary approach does not claim to be the answer to all issues concerning the wise use of new technologies. But it does point the way to how we can use public policy frameworks and processes to guide and constrain technological developments in the most appropriate way, and avoid some of the worst possible outcomes. At a time of accelerating technological change and overwhelming human dominance of the natural environment it is vital that we make wise use of this approach.

  8. The influence of static pre-stretching on the mechanical ageing of filled silicone rubbers for dielectric elastomer applications

    DEFF Research Database (Denmark)

    Zakaria, Shamsul Bin; Yu, Liyun; Kofod, Guggi

    2015-01-01

    Dielectric elastomer (DE) pre-stretching is a key aspect of attaining better actuation performance, as ithelps prevent electromechanical instability (EMI) and usually lowers the Young’s modulus, thus leading toeasier deformation. The pre-stretched DE is not only susceptible to a high risk...

  9. COMPARATIVE EFFECT OF STATIC AND DYNAMIC STRETCHING EXERCISE TO IMPROVE FLEXIBILITY OF HAMSTRING MUSCLES AMONG NON ATHLETES

    Directory of Open Access Journals (Sweden)

    Jibi Paul

    2014-10-01

    Full Text Available Background: Stretching exercises have been routinely used in persons with hamstring tightness and athletes to increase flexibility of muscle and to reduce joint injuries. Many studies have reported effect of static and dynamic stretching on flexibility of this muscle. Finding the best method to improve flexibility of hamstring muscle is important for athletes and individuals to reduce their injuries. Objective of the study was to find out the effect of static stretching exercise and dynamic stretching exercise on flexibility of hamstring muscle and also to compare the effect of static and dynamic stretching exercise on flexibility of hamstring muscle. Methods: This was a comparative experimental study with seventy four female healthy subjects from physiotherapy department of KPJ Healthcare University College, Malaysia. Convenient sampling method used to select the samples. The subjects were selected by inclusion criteria and randomly divided equally in to two with 37 subjects in each group. Static stretching exercise and dynamic stretching exercise were given as intervention program for four weeks respectively for experimental and control group. Pre and post data of restricted range of movement for knee extension was measured using goniometry and documented separately for both group. Result: In experimental and control group, pre-post statistical analysis found significant effect in increase of hamstring flexibility with P<0.0001, for right and left side. Comparative study between experimental and control group found that static stretching exercise have significant effect in increase of hamstring flexibility for right and left side with P<0.04. Conclusion: This study concluded that static stretching exercise is more effective to improve hamstring flexibility compared to dynamic stretching exercise.

  10. The passive hamstring stretch test: clinical evaluation.

    Science.gov (United States)

    Fisk, J W

    1979-03-28

    The passive hamstring stretch test is described. Using a modified goniometer it is shown that independent measurements taken by trained examiners approximate very closely to each other. This establishes the test as a valid objective measurement. The possible value of this test as a research tool in low back pain problems is discussed.

  11. Optical stretching on chip with acoustophoretic prefocusing

    DEFF Research Database (Denmark)

    Khoury Arvelo, Maria; Laub Busk, L.; Bruus, Henrik

    2012-01-01

    in the microchannel. Trapping and manipulation is demonstrated for dielectric beads. In addition, we show trapping, manipulation and stretching of red blood cells and vesicles, whereby we extract the elastic properties of these objects. Our design points towards the construction of a low-cost, high-throughput lab...

  12. Filament stretching rheometry of polymer melts

    DEFF Research Database (Denmark)

    Hassager, Ole; Nielsen, Jens Kromann; Rasmussen, Henrik Koblitz

    2005-01-01

    The Filament Stretching Rheometry (FSR) method developed by Sridhar, McKinley and coworkers for polymer solutions has been extended to be used also for polymer melts. The design of a melt-FSR will be described and differences to conventional melt elongational rheometers will be pointed out. Results...

  13. Do Dental Students' Personality Types and Group Dynamics Affect Their Performance in Problem-Based Learning?

    Science.gov (United States)

    Ihm, Jung-Joon; An, So-Youn; Seo, Deog-Gyu

    2017-06-01

    The aim of this study was to determine whether the personality types of dental students and their group dynamics were linked to their problem-based learning (PBL) performance. The Myers-Briggs Type Indicator (MBTI) instrument was used with 263 dental students enrolled in Seoul National University School of Dentistry from 2011 to 2013; the students had participated in PBL in their first year. A four-session PBL setting was designed to analyze how individual personality types and the diversity of their small groups were associated with PBL performance. Overall, the results showed that the personality type of PBL performance that was the most prominent was Judging. As a group became more diverse with its different constituent personality characteristics, there was a tendency for the group to be higher ranked in terms of PBL performance. In particular, the overperforming group was clustered around three major profiles: Extraverted Intuitive Thinking Judging (ENTJ), Introverted Sensing Thinking Judging (ISTJ), and Extraverted Sensing Thinking Judging (ESTJ). Personality analysis would be beneficial for dental faculty members in order for them to understand the extent to which cooperative learning would work smoothly, especially when considering group personalities.

  14. Stretching single fibrin fibers hampers their lysis.

    Science.gov (United States)

    Li, Wei; Lucioni, Tomas; Li, Rongzhong; Bonin, Keith; Cho, Samuel S; Guthold, Martin

    2017-09-15

    Blood clots, whose main structural component is a mesh of microscopic fibrin fibers, experience mechanical strain from blood flow, clot retraction and interactions with platelets and other cells. We developed a transparent, striated and highly stretchable substrate made from fugitive glue (a styrenic block copolymer) to investigate how mechanical strain affects lysis of single, suspended fibrin fibers. In this suspended fiber assay, lysis manifested itself by fiber elongation, thickening (disassembly), fraying and collapse. Stretching single fibrin fibers significantly hampered their lysis. This effect was seen in uncrosslinked and crosslinked fibers. Crosslinking (without stretching) also hampered single fiber lysis. Our data suggest that strain is a novel mechanosensitive factor that regulates blood clot dissolution (fibrinolysis) at the single fiber level. At the molecular level of single fibrin molecules, strain may distort, or hinder access to, plasmin cleavage sites and thereby hamper lysis. Fibrin fibers are the major structural component of a blood clot. We developed a highly stretchable substrate made from fugitive glue and a suspended fibrin fiber lysis assay to investigate the effect of stretching on single fibrin fibers lysis. The key findings from our experiments are: 1) Fibers thicken and elongate upon lysis; 2) stretching strongly reduces lysis; 3) this effect is more pronounced for uncrosslinked fibers; and 4) stretching fibers has a similar effect on reducing lysis as crosslinking fibers. At the molecular level, strain may distort plasmin cleavage sites, or restrict access to those sites. Our results suggest that strain may be a novel mechanobiological factor that regulates fibrinolysis. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  15. Coherent time-stretch transformation for real-time capture of wideband signals.

    Science.gov (United States)

    Buckley, Brandon W; Madni, Asad M; Jalali, Bahram

    2013-09-09

    Time stretch transformation of wideband waveforms boosts the performance of analog-to-digital converters and digital signal processors by slowing down analog electrical signals before digitization. The transform is based on dispersive Fourier transformation implemented in the optical domain. A coherent receiver would be ideal for capturing the time-stretched optical signal. Coherent receivers offer improved sensitivity, allow for digital cancellation of dispersion-induced impairments and optical nonlinearities, and enable decoding of phase-modulated optical data formats. Because time-stretch uses a chirped broadband (>1 THz) optical carrier, a new coherent detection technique is required. In this paper, we introduce and demonstrate coherent time stretch transformation; a technique that combines dispersive Fourier transform with optically broadband coherent detection.

  16. Intrinsic ankle stiffness during standing increases with ankle torque and passive stretch of the Achilles tendon

    Science.gov (United States)

    Gill, Jaspret

    2018-01-01

    Individuals may stand with a range of ankle angles. Furthermore, shoes or floor surfaces may elevate or depress their heels. Here we ask how these situations impact ankle stiffness and balance. We performed two studies (each with 10 participants) in which the triceps surae, Achilles tendon and aponeurosis were stretched either passively, by rotating the support surface, or actively by leaning forward. Participants stood freely on footplates which could rotate around the ankle joint axis. Brief, small stiffness-measuring perturbations (torque or passive stretch. Sway was minimally affected by stretch or lean, suggesting that this did not underlie the alterations in stiffness. In quiet stance, maximum ankle stiffness is limited by the tendon. As tendon strain increases, it becomes stiffer, causing an increase in overall ankle stiffness, which would explain the effects of leaning. However, stiffness also increased considerably with passive stretch, despite a modest torque increase. We discuss possible explanations for this increase. PMID:29558469

  17. Reducing charging effects in scanning electron microscope images by Rayleigh contrast stretching method (RCS).

    Science.gov (United States)

    Wan Ismail, W Z; Sim, K S; Tso, C P; Ting, H Y

    2011-01-01

    To reduce undesirable charging effects in scanning electron microscope images, Rayleigh contrast stretching is developed and employed. First, re-scaling is performed on the input image histograms with Rayleigh algorithm. Then, contrast stretching or contrast adjustment is implemented to improve the images while reducing the contrast charging artifacts. This technique has been compared to some existing histogram equalization (HE) extension techniques: recursive sub-image HE, contrast stretching dynamic HE, multipeak HE and recursive mean separate HE. Other post processing methods, such as wavelet approach, spatial filtering, and exponential contrast stretching, are compared as well. Overall, the proposed method produces better image compensation in reducing charging artifacts. Copyright © 2011 Wiley Periodicals, Inc.

  18. Organizational citizenship behavior and the quantity and quality of work group performance.

    Science.gov (United States)

    Podsakoff, P M; Ahearne, M; MacKenzie, S B

    1997-04-01

    Despite the widespread interest in the topic of organizational citizenship behaviors (OCBs), little empirical research has tested the fundamental assumption that these forms of behavior improve the effectiveness of work groups or organizations in which they are exhibited. In the present study, the effects of OCBs on the quantity and quality of the performance of 218 people working in 40 machine crews in a paper mill located in the Northeastern United States were examined. The results indicate that helping behavior and sportsmanship had significant effects on performance quantity and that helping behavior had a significant impact on performance quality. However, civic virtue had no effect on either performance measure.

  19. Performance of 12Ah aerospace nickel-cadmium cells of design variable groups

    Science.gov (United States)

    Vasanth, K. L.

    1985-01-01

    The design variable program of NASA is a systematic approach to evaluate the performance of 12Ah aerospace nickel-cadmium cells of 9 important cell designs. These cells were life cycled in a Low-Earth Orbit (LEO) regime for 3 to 4 years. Representative cells taken from the design variable groups after different cycling periods have been examined. The results show that: (1) positive swelling and carbonate content in the electrolyte increases as a function of the number of cycles, (2) electrolyte distribution follows the order NEG greater than POS greater than SEP, 3) control and no PQ groups outperformed the rest of the groups and (4) the polypropylene group shows very heavy cadmium migration and poor performance.

  20. Does the group leader matter? The impact of monitoring activities and social ties of group leaders on the repayment performance of groupbased lending Eritrea

    NARCIS (Netherlands)

    Hermes, Niels; Lensink, Robert; Mehrteab, Habteab T.

    2005-01-01

    This paper analyzes whether the effects of monitoring and social ties of the group leader and other group members on repayment performance of groups differ, using data from an extensive questionnaire held in Eritrea among participants of 102 groups. We hypothesize that the monitoring activities and

  1. Small business groups enhance performance and promote stability, not expropriation. Evidence from French SMEs

    OpenAIRE

    Anaïs Hamelin

    2010-01-01

    This paper investigates the influence of a firm’s distance from control on its performance, using a unique firm level data set on small business ownership, as well as balance sheet information. This study fills a gap in the empirical governance literature by investigating whether or not there is an expropriation of minority shareholders in small business groups. Contrary to what is usually observed for large business groups, results show a positive relationship between the separation of contr...

  2. How to determine local stretching and tension in a flow-stretched DNA molecule

    DEFF Research Database (Denmark)

    Pedersen, Jonas Nyvold; Marie, Rodolphe; Kristensen, Anders

    2016-01-01

    We determine the nonuniform stretching of and tension in amega base pairs-long fragment of deoxyribonucleic acid (DNA) that is flow stretched in a nanofluidic chip. We use no markers, do not know the contour length of the DNA, and do not have the full DNA molecule inside our field of view. Instead......, we analyze the transverse thermal motion of the DNA. Tension at the center of the DNA adds up to 16 pN, giving almost fully stretched DNA. This method was devised for optical mapping of DNA, specifically, DNA denaturation patterns. It may be useful also for other studies, e.g., DNA......-protein interactions, specifically, their tension dependence. Generally, wherever long strands of DNA—e.g., native DNA extracted from human cells or bacteria—must be stretched with ease for inspection, this method applies....

  3. Fatigue and muscle-tendon stiffness after stretch-shortening cycle and isometric exercise.

    Science.gov (United States)

    Toumi, Hechmi; Poumarat, Georges; Best, Thomas M; Martin, Alain; Fairclough, John; Benjamin, Mike

    2006-10-01

    The purpose of the present study was to compare vertical jump performance after 2 different fatigue protocols. In the first protocol, subjects performed consecutive sets of 10 repetitions of stretch-shortening cycle (SSC) contractions. In the second protocol, successive sets of 10 repetitions of isometric contractions were performed for 10 s with the knee at 90 degrees of flexion. The exercises were stopped when the subjects failed to reach 50% of their maximum voluntary isometric contractions. Maximal isometric force and maximal concentric power were assessed by performing supine leg presses, squat jumps, and drop jumps. Surface EMG was used to determine changes in muscle activation before and after fatigue. In both groups, the fatigue exercises reduced voluntary isometric force, maximal concentric power, and drop jump performance. Kinematic data showed a decrease in knee muscle-tendon stiffness accompanied by a lengthened ground contact time. EMG analysis showed that the squat and drop jumps were performed similarly before and after the fatigue exercise for both groups. Although it was expected that the stiffness would decrease more after SSC than after isometric fatigue (as a result of a greater alteration of the reflex sensitivity SSC), our results showed that both protocols had a similar effect on knee muscle stiffness during jumping exercises. Both fatigue protocols induced muscle fatigue, and the decrease in jump performance was linked to a decrease in the strength and stiffness of the knee extensor muscles.

  4. Flexibility and stretching physiology : responses and adaptations to different stretching intensities.

    OpenAIRE

    Freitas, Sandro Remo Martins Neves Ramos

    2014-01-01

    Doutoramento em Motricidade Humana, especialidade de Biomecânica Research and reported literature regarding the conceptual, methodological, and training effects of stretching with different intensities are scarce. The purposes of this thesis were to: i) explore and develop methodological conditions to achieve the second purpose (studies: 1 to 3); ii) characterize the acute and chronic effects induced by different stretching intensities on skeletal muscle and joint mechanical properti...

  5. Performance-influencing factors in homogeneous groups of top athletes: a cross-sectional study

    OpenAIRE

    van Ingen Schenau, G.J.; Bakker, F.C.; de Koning, J.J.; de Groot, G.

    1996-01-01

    Sport scientists have identified many factors as prerequisites for a good athletic performance in various sports. It is not clear whether these factors also influence the best performers in the homogeneous groups of top athletes selected for national teams. In this study, this issue is addressed with members of the Dutch National Junior Speed Skirting Team. A total of 237 different technical, physiological, anthropometrical, and psychological parameters were collected, including many that cor...

  6. Three Levels of Diversity: An Examination of the Complex Relationship Between Diversity, Group Cohesiveness, Sexual Harassment, Group Performance, and Time

    National Research Council Canada - National Science Library

    Whaley, Gary

    1998-01-01

    ...: surface, working, and deep level diversity. The author explains the nature of the relationship between the three levels of diversity and posits a general model of organizational behavior including diversity, group cohesiveness, group...

  7. Effectiveness of the Simultaneous Stretching of the Achilles Tendon and Plantar Fascia in Individuals With Plantar Fasciitis.

    Science.gov (United States)

    Engkananuwat, Phoomchai; Kanlayanaphotporn, Rotsalai; Purepong, Nithima

    2018-01-01

    Since the plantar fascia and the Achilles tendon are anatomically connected, it is plausible that stretching of both structures simultaneously will result in a better outcome for plantar fasciitis. Fifty participants aged 40 to 60 years with a history of plantar fasciitis greater than 1 month were recruited. They were prospectively randomized into 2 groups. Group 1 was instructed to stretch the Achilles tendon while group 2 simultaneously stretched the Achilles tendon and plantar fascia. After 4 weeks of both stretching protocols, participants in group 2 demonstrated a significantly greater pressure pain threshold than participants in group 1 ( P = .040) with post hoc analysis. No significant differences between groups were demonstrated in other variables ( P > .05). Concerning within-group comparisons, both interventions resulted in significant reductions in pain at first step in the morning and average pain at the medial plantar calcaneal region over the past 24 hours, while there were increases in the pressure pain threshold, visual analog scale-foot and ankle score, and range of motion in ankle dorsiflexion ( P plantar fascia for 4 weeks was a more effective intervention for plantar fasciitis. Patients who reported complete relief from symptoms at the end of the 4-week intervention in the simultaneous stretching group (n = 14; 56%) were double that of the stretching of the Achilles tendon-only group (n = 7; 28%). II, lesser quality RCT or prospective comparative study.

  8. Learning Performance Enhancement Using Computer-Assisted Language Learning by Collaborative Learning Groups

    Directory of Open Access Journals (Sweden)

    Ya-huei Wang

    2017-08-01

    Full Text Available This study attempted to test whether the use of computer-assisted language learning (CALL and innovative collaborative learning could be more effective than the use of traditional collaborative learning in improving students’ English proficiencies. A true experimental design was used in the study. Four randomly-assigned groups participated in the study: a traditional collaborative learning group (TCLG, 34 students, an innovative collaborative learning group (ICLG, 31 students, a CALL traditional collaborative learning group (CALLTCLG, 32 students, and a CALL innovative collaborative learning group (CALLICLG, 31 students. TOEIC (Test of English for International Communication listening, reading, speaking, and writing pre-test and post-test assessments were given to all students at an interval of sixteen weeks. Multivariate analysis of covariance (MANCOVA, multivariate analysis of variance (MANOVA, and analysis of variance (ANOVA were used to analyze the data. The results revealed that students who used CALL had significantly better learning performance than those who did not. Students in innovative collaborative learning had significantly better learning performances than those in traditional collaborative learning. Additionally, students using CALL innovative collaborative learning had better learning performances than those in CALL collaborative learning, those in innovative collaborative learning, and those in traditional collaborative learning.

  9. Investigating the Effects of Group Practice Performed Using Psychodrama Techniques on Adolescents' Conflict Resolution Skills

    Science.gov (United States)

    Karatas, Zeynep

    2011-01-01

    The aim of this study is to examine the effects of group practice which is performed using psychodrama techniques on adolescents' conflict resolution skills. The subjects, for this study, were selected among the high school students who have high aggression levels and low problem solving levels attending Haci Zekiye Arslan High School, in Nigde.…

  10. Effects of sweeteners on individual feed intake characteristics and performance in group-housed weanling pigs

    NARCIS (Netherlands)

    Sterk, A.R.; Schlegel, P.; Mul, A.J.; Ubbink-Blanksma, M.; Bruininx, E.M.A.M.

    2008-01-01

    To assess the effects of 2 high intensity sodium saccharine based sweeteners on individual feed intake characteristics and performance of group-housed weaned pigs, 198 26-d-old weanling pigs were given ad libitum access to 3 dietary treatments: containing no additional sweetener (Control), 150 mg

  11. Using Differential Item Functioning Procedures to Explore Sources of Item Difficulty and Group Performance Characteristics.

    Science.gov (United States)

    Scheuneman, Janice Dowd; Gerritz, Kalle

    1990-01-01

    Differential item functioning (DIF) methodology for revealing sources of item difficulty and performance characteristics of different groups was explored. A total of 150 Scholastic Aptitude Test items and 132 Graduate Record Examination general test items were analyzed. DIF was evaluated for males and females and Blacks and Whites. (SLD)

  12. Importance-performance analysis of dental satisfaction among three ethnic groups in malaysia.

    Science.gov (United States)

    Dewi, Fellani Danasra; Gundavarapu, Kalyan C; Cugati, Navaneetha

    2013-01-01

    To find the differences in patient satisfaction related to dental services among three ethnic groups - Chinese, Indian and Malay - at AIMST University Dental Centre and analyse them with an importance-performance grid, identifying the weak and strong points, in order to provide better service. This questionnaire-based study consisted of convenience samples of 174 patients of Chinese, Indian and Malay ethnicity. Importance-performance analysis for 20 attributes were compared using Likert's scale. The data obtained were statistically analysed using the Kruskal-Wallis test. Chinese and Indians both emphasised low performance on the interpersonal relationship attribute in terms of the receptionist's courtesy, whereas the Malay participants were concerned with convenience attributes. All the ethnic groups favoured maintaining existing major attributes towards technical competency, interpersonal relationship and facility factors. This study demonstrated priority differences between the ethnic groups' perception of the quality of dental services, where ethnic Chinese showed the highest gap (measure of dissatisfaction) between importance and performance compared to ethnic Malays, followed by ethnic Indians. The patients from the three major ethnic groups of Malaysia were generally well satisfied. Perhaps more priority should be placed on improving the interpersonal relationship attribute, especially with the receptionists.

  13. Interteaching: The Effects of Discussion Group Size on Undergraduate Student Performance and Preference

    Science.gov (United States)

    Gutierrez, Michael

    2017-01-01

    Interteaching is a college teaching method grounded in the principles of applied behavior analysis. Research on interteaching demonstrates that it improves academic performance, and students report greater satisfaction with interteaching as compared to traditional teaching styles. The current study investigates whether discussion group size, a…

  14. Impact of Group Emotions on Student Collective Action Tendencies, Ties, and Task Performance

    Science.gov (United States)

    Sundararajan, Malavika; Sundararajan, Binod; Manderson, Jill

    2016-01-01

    The authors tested the dynamics of collective action tendencies of student teams when trying to accomplish a shared goal, with a focus on the impact of member ties and team member interaction and emotional responses on team performance. The results show the direct and indirect impacts of both positive and negative group emotions on the student…

  15. Performance Assessment and the Components of the Oral Construct across Different Tasks and Rater Groups.

    Science.gov (United States)

    Chalhoub-Deville, Micheline

    This study investigated whether different groups of native speakers assess second language learners' language skills differently for three elicitation techniques. Subjects were six learners of college-level Arabic as a second language, tape-recorded performing three tasks: participating in a modified oral proficiency interview, narrating a picture…

  16. The Relationships among Group Size, Participation, and Performance of Programming Language Learning Supported with Online Forums

    Science.gov (United States)

    Shaw, Ruey-Shiang

    2013-01-01

    This study examined the relationships among group size, participation, and learning performance factors when learning a programming language in a computer-supported collaborative learning (CSCL) context. An online forum was used as the CSCL environment for learning the Microsoft ASP.NET programming language. The collaborative-learning experiment…

  17. Analysis of postural control and muscular performance in young and elderly women in different age groups.

    Science.gov (United States)

    Gomes, Matheus M; Reis, Júlia G; Carvalho, Regiane L; Tanaka, Erika H; Hyppolito, Miguel A; Abreu, Daniela C C

    2015-01-01

    muscle strength and power are two factors affecting balance. The impact of muscle strength and power on postural control has not been fully explored among different age strata over sixty. the aim of the present study was to assess the muscle strength and power of elderly women in different age groups and determine their correlation with postural control. eighty women were divided into four groups: the young 18-30 age group (n=20); the 60-64 age group (n=20); the 65-69 age group (n=20); and the 70-74 age group (n=20). The participants underwent maximum strength (one repetition maximum or 1-RM) and muscle power tests to assess the knee extensor and flexor muscles at 40%, 70%, and 90% 1-RM intensity. The time required by participants to recover their balance after disturbing their base of support was also assessed. the elderly women in the 60-64, 65-69, and 70-74 age groups exhibited similar muscle strength, power, and postural control (p>0.05); however, these values were lower than those of the young group (ppostural control performance (ppostural control shown by these women.

  18. Effects of high-intensity pulse irradiation with linear polarized near-infrared rays and stretching on muscle tone in patients with cerebrovascular disease: a randomized controlled trial.

    Science.gov (United States)

    Takeuchi, Nobuyuki; Takezako, Nobuhiro; Shimonishi, Yuko; Usuda, Shigeru

    2017-08-01

    [Purpose] The purpose of this study was to clarify the influence of high-intensity pulse irradiation with linear polarized near-infrared rays (HI-LPNR) and stretching on hypertonia in cerebrovascular disease patients. [Subjects and Methods] The subjects were 40 cerebrovascular disease patients with hypertonia of the ankle joint plantar flexor muscle. The subjects were randomly allocated to groups undergoing treatment with HI-LPNR irradiation (HI-LPNR group), stretching (stretching group), HI-LPNR irradiation followed by stretching (combination group), and control group (10 subjects each). In all groups, the passive range of motion of ankle dorsiflexion and passive resistive joint torque of ankle dorsiflexion were measured before and after the specified intervention. [Results] The changes in passive range of motion, significant increase in the stretching and combination groups compared with that in the control group. The changes in passive resistive joint torque, significant decrease in HI-LPNR, stretching, and combination groups compared with that in the control group. [Conclusion] HI-LPNR irradiation and stretching has effect of decrease muscle tone. However, combination of HI-LPNR irradiation and stretching has no multiplier effect.

  19. The influence of stretching on tensile strength and solubility of poly(vinyl alcohol) fibres

    NARCIS (Netherlands)

    Heikens, D.; Bleijenberg, A.C.A.M.; Hoppenbrouwers, J.J.M.; Barentsen, W.M.

    1971-01-01

    The strength of wet-spun poly(vinyl alcohol) (pva) fibres is given as function of bath-stretching, wet-stretching and hot-stretching. In the two equations derived for strength of wet-stretching and hot-stretching the complex influence of the bath-stretching and hot-stretching is demonstrated. The

  20. Stretch strength of Al-Li alloy sheet

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K.; Sawa, Y.; Yokoyama, T.; Fujimoto, S. [Science Univ. of Tokyo (Japan). Dept. of Mech. Eng.; Sakamoto, T. [Kobe Steel Works, Tokyo (Japan)

    1998-07-01

    Stretch test on Al-Li alloy sheet was carried out in stretch rate of 0.01 to 0.2 mm/sec. The limiting stretch depth was measured in various conditions and the following results were obtained. (1) Stretch rate does not affect the limiting stretch depth of Al-Li alloy. (2) The limiting stretch depth is increased with increase of the profile radius. (3) Strain hardening exponent(n-value) and r-value of Lankford do not affect the limiting stretch depth. (4) Rapture pattern in stretch test of Al is {alpha} type rapture and that of Al-Li alloy is straight line type rapture. (orig.) 4 refs.

  1. [Sciatica. From stretch rack to microdiscectomy].

    Science.gov (United States)

    Gruber, P; Böni, T

    2015-12-01

    In ancient times as well as in the Middle Ages treatment options for discogenic nerve compression syndrome were limited and usually not very specific because of low anatomical and pathophysiological knowledge. The stretch rack (scamnum Hippocratis) was particularly prominent but was widely used as a therapeutic device for very different spinal disorders. Since the beginning of the nineteenth century anatomical knowledge increased and the advances in the fields of asepsis, anesthesia and surgery resulted in an increase in surgical interventions on the spine. In 1908 the first successful lumbar discectomy was initiated and performed by the German neurologist Heinrich O. Oppenheim (1858-1919) and the surgeon Fedor Krause (1857-1937); however, neither recognized the true pathological condition of discogenic nerve compression syndrome. With the landmark report in the New England Journal of Medicine in 1934, the two American surgeons William Jason Mixter (1880-1958) and Joseph Seaton Barr (1901-1963) finally clarified the pathomechanism of lumbar disc herniation and furthermore, propagated discectomy as the standard therapy. Since then interventions on intervertebral discs rapidly increased and the treatment options for lumbar disc surgery quickly evolved. The surgical procedures changed over time and were continuously being refined. In the late 1960s the surgical microscope was introduced for spinal surgery by the work of the famous neurosurgeon Mahmut Gazi Yasargil and his colleague Wolfhard Caspar and so-called microdiscectomy was introduced. Besides open discectomy other interventional techniques were developed to overcome the side effects of surgical procedures. In 1964 the American orthopedic surgeon Lyman Smith (1912-1991) introduced chemonucleolysis, a minimally invasive technique consisting only of a cannula and the proteolytic enzyme chymopapain, which is injected into the disc compartment to dissolve the displaced disc material. In 1975 the Japanese orthopedic

  2. Effects of communication strategy training on EFL students’ performance in small-group discussions

    Directory of Open Access Journals (Sweden)

    Stuart Benson

    2013-10-01

    Full Text Available In recent years, a number of studies have been conducted with regard to communication strategy training and performance on communicative tasks (Lam, 2009; Nakatani, 2010; Naughton, 2006. This study aims to add to the literature by examining how two strategies, clarifying/confirming and extending a conversation, and two methods of teaching the strategies, affected the interactional sequences and overall group discussion performance of EFL students at a university in Japan. Pre and posttreatment small-group discussions were recorded for assessment, and a stimulated recall interview was administered to determine the participants’ perceptions of their learning and language use. Posttest results reveal that the experimental groups that were taught predetermined phrases aimed at clarifying/confirming and extending a conversation employed such phrases more frequently than the control group. However, this employment of phrases did not lead to higher gains in group discussion skills as the control group enjoyed the largest gains from pre to posttest. The researchers consider the findings in light of previous research, and conclude with recommendations for future research on the topic with special regard to research design.

  3. Mechanical stretch induces MMP-2 release and activation in lung endothelium: role of EMMPRIN.

    Science.gov (United States)

    Haseneen, Nadia A; Vaday, Gayle G; Zucker, Stanley; Foda, Hussein D

    2003-03-01

    High-volume mechanical ventilation leads to ventilator-induced lung injury. This type of lung injury is accompanied by an increased release and activation of matrix metalloproteinases (MMPs). To investigate the mechanism leading to the increased MMP release, we systematically studied the effect of mechanical stretch on human microvascular endothelial cells isolated from the lung. We exposed cells grown on collagen 1 BioFlex plates to sinusoidal cyclic stretch at 0.5 Hz using the Flexercell system with 17-18% elongation of cells. After 4 days of cell stretching, conditioned media and cell lysate were collected and analyzed by gelatin, casein, and reverse zymograms as well as Western blotting. RT-PCR of mRNA extracted from stretched cells was performed. Our results show that 1) cyclic stretch led to increased release and activation of MMP-2 and MMP-1; 2) the activation of MMP-2 was accompanied by an increase in membrane type-1 MMP (MT1-MMP) and inhibited by a hydroxamic acid-derived inhibitor of MMPs (Prinomastat, AG3340); and 3) the MMP-2 release and activation were preceded by an increase in production of extracellular MMP inducer (EMMPRIN). These results suggest that cyclic mechanical stretch leads to MMP-2 activation through an MT1-MMP mechanism. EMMPRIN may play an important role in the release and activation of MMPs during lung injury.

  4. String Stretching, Frequency Modulation, and Banjo Clang

    OpenAIRE

    Politzer, David

    2014-01-01

    The banjo’s floating bridge, string break angle, and flexible drumhead all contribute to substantial audio range frequency modulation. From the world of electronic music synthesis, it is known that modulating higher frequency sounds with lower acoustic frequencies leads to metallic and bell-like tone. The mechanics of the banjo does just that quite naturally, modulating fundamentals and harmonics with the motion of the bridge. In technical terms, with a floating bridge, string stretching is f...

  5. The stretch zone of automotive steel sheets

    Indian Academy of Sciences (India)

    The stretch zone of automotive steel sheets. L' AMBRIŠKO1,∗ and L PEŠEK2. 1Institute of Structural Engineering, Faculty of Civil Engineering,. Technical University of Košice, Vysokoškolská 4, 042 00 Košice, Slovak Republic. 2Department of Materials Science, Faculty of Metallurgy,. Technical University of Košice, Letná 9, ...

  6. The effect of workshop groups on achievement goals and performance in biology: An outcome evaluation

    Science.gov (United States)

    Born, Wendi Kay

    This two-year quasi-experiment evaluated the effect of peer-led workshop groups on performance of minority and majority undergraduate biology students in a three-course series and investigated motivational explanations for performance differences. The workshop intervention used was modeled after a program pioneered by Treisman (1992) at the University of California. Majority volunteers randomly assigned to workshops (n = 61) performed between 1/2 and 1 standard deviation better than those assigned to the control group (n = 60; p challenge interventions can be highly beneficial for both majority and minority participants and that institutions can promote excellence by incorporating workshop programs like the one described here. These interventions have been shown to be more effective and cost less than remedial interventions.

  7. Spontaneous bending of pre-stretched bilayers.

    Science.gov (United States)

    DeSimone, Antonio

    2018-01-01

    We discuss spontaneously bent configurations of pre-stretched bilayer sheets that can be obtained by tuning the pre-stretches in the two layers. The two-dimensional nonlinear plate model we use for this purpose is an adaptation of the one recently obtained for thin sheets of nematic elastomers, by means of a rigorous dimensional reduction argument based on the theory of Gamma-convergence (Agostiniani and DeSimone in Meccanica. doi:10.1007/s11012-017-0630-4, 2017, Math Mech Solids. doi:10.1177/1081286517699991, arXiv:1509.07003, 2017). We argue that pre-stretched bilayer sheets provide us with an interesting model system to study shape programming and morphing of surfaces in other, more complex systems, where spontaneous deformations are induced by swelling due to the absorption of a liquid, phase transformations, thermal or electro-magnetic stimuli. These include bio-mimetic structures inspired by biological systems from both the plant and the animal kingdoms.

  8. Dynamics and structure of stretched flames

    Energy Technology Data Exchange (ETDEWEB)

    Law, C.K. [Princeton Univ., NJ (United States)

    1993-12-01

    This program aims to gain fundamental understanding on the structure, geometry, and dynamics of laminar premixed flames, and relate these understanding to the practical issues of flame extinction and stabilization. The underlying fundamental interest here is the recent recognition that the response of premixed flames can be profoundly affected by flame stretch, as manifested by flow nonuniformity, flame curvature, and flame/flow unsteadiness. As such, many of the existing understanding on the behavior of premixed flames need to be qualitatively revised. The research program consists of three major thrusts: (1) detailed experimental and computational mapping of the structure of aerodynamically-strained planar flames, with emphasis on the effects of heat loss, nonequidiffusion, and finite residence time on the flame thickness, extent of incomplete reaction, and the state of extinction. (2) Analytical study of the geometry and dynamics of stretch-affected wrinkled flame sheets in simple configurations, as exemplified by the Bunsen flame and the spatially-periodic flame, with emphasis on the effects of nonlinear stretch, the phenomena of flame cusping, smoothing, and tip opening, and their implications on the structure and burning rate of turbulent flames. (3) Stabilization and blowoff of two-dimensional inverted premixed and stabilization and determining the criteria governing flame blowoff. The research is synergistically conducted through the use of laser-based diagnostics, computational simulation of the flame structure with detailed chemistry and transport, and mathematical analysis of the flame dynamics.

  9. Performance and Health of Group-Housed Calves Kept in Igloo Calf Hutches and Calf Barn

    Directory of Open Access Journals (Sweden)

    Jerzy Wójcik*, Renata Pilarczyk, Anna Bilska, Ottfried Weiher1 and Peter Sanftleben1

    2013-04-01

    Full Text Available Group-reared calves are usually housed in common buildings, such as calf barns of all sorts; however, there are concerns about this practice due to problems such as an increased incidence of diseases and poor performance of the calves. Group calf rearing using igloo hutches may be a solution combining the benefits of individual and group housing systems. The aim of this study was to evaluate group-reared calves housed in Igloo-type hutches compared with those housed in common calf barns. The experiment was carried out on a large private dairy farm located in Vorpommern, Germany. A total of 90 Deutsche-Holstein bull calves were assigned to 2 treatment groups: the calf-barn group, with calves grouped in pens in a building, and the Igloo-hutch group, with calves housed in outdoor enclosures with an access to group igloo-style hutches. Calves entering the 84-day experiment were at an average age of about three weeks, with the mean initial body weight of about 50 kg. The calves housed in the group Igloo hutches attained higher daily weight gains compared to those housed in the calf barn (973 vs 721 g/day, consumed more solid feeds (concentrate, corn grain and maize silage: (1.79 vs 1.59 kg/day, and less milk replacer (5.51 vs 6.19 kg/day, had also a lower incidence of respiratory diseases (1.24 vs 3.57% with a shorter persistence of the illness.

  10. When sad groups expect to meet again : Interactive affective sharing and future interaction expectation as determinants of work groups' analytical and creative task performance

    NARCIS (Netherlands)

    Klep, Annefloor H. M.; Wisse, Barbara; van der Flier, Henk

    2013-01-01

    The present study examines the moderating role of future interaction expectation in the relationship between affective sharing and work groups' task performance. We argue that group affect, a group defining characteristic, becomes more salient to its members when it is interactively shared, and that

  11. Investigation on thermomechanical properties of poly (l-lactic acid) for the stretch blow moulding process of bioresorbable vascular scaffold

    Science.gov (United States)

    Wei, Huidong; Menary, Gary

    2017-10-01

    Stretch blow moulding process has been used for the manufacture of bioresorbable vascular scaffold (BVS) made by poly (l-lactic acid) (PLLA) to improve its mechanical performance. In order to better understand the process, thermomechanical properties of PLLA were investigated by experimental method. Extruded PLLA sheets were biaxial stretched under strain rate of 1s-1, 4s-1 and 16s-1 to simulate the deformation process applicable in the blow moulding process. Both the equal-biaxial stretch and constant-width stretch were conducted by an in-house developed equipment. By differential scanning calorimeter (DSC), thermal analysis for materials before and after stretch were compared to evaluate the microstructural change of PLLA materials in the deformation process. A constitutive model based on glass rubber model was presented to simulate the mechanical behaviour of PLLA above glass transition under biaxial deformation.

  12. When none of us perform better than all of us together : The role of analogical decision rules in groups

    NARCIS (Netherlands)

    Meslec, M.N.; Curseu, P.L.; Meeus, M.T.H.; Fodor, O.C.

    2014-01-01

    During social interactions, groups develop collective competencies that (ideally) should assist groups to outperform average standalone individual members (weak cognitive synergy) or the best performing member in the group (strong cognitive synergy). In two experimental studies we manipulate the

  13. Dyads and triads at 35,000 feet - Factors affecting group process and aircrew performance

    Science.gov (United States)

    Foushee, H. C.

    1984-01-01

    The task of flying a multipilot transport aircraft is a classic small-group performance situation where a number of social, organizational, and personality factors are relevant to important outcome variables such as safety. The aviation community is becoming increasingly aware of the importance of these factors but is hampered in its efforts to improve the system because of research psychology's problems in defining the nature of the group process. This article identifies some of the problem areas as well as methods used to address these issues. It is argued that high fidelity flight simulators provide an environment that offers unique opportunities for work meeting both basic and applied research criteria.

  14. Dyads and triads at 35,000 feet: Factors affecting group process and aircrew performance

    Science.gov (United States)

    Foushee, H. Clayton

    1987-01-01

    The task of flying a multipilot transport aircraft is a classic small-group performance situation where a number of social, organizational, and personality factors are relevant to important outcome variables such as safety. The aviation community is becoming increasingly aware of the importance of these factors but is hampered in its efforts to improve the system because of research psychology's problems in defining the nature of the group process. This article identifies some of the problem areas as well as methods used to address these issues. It is argued that high fidelity flight simulators provide an environment that offers unique opportunities for work meeting both basic and applied research criteria.

  15. STUDY TO COMPARE THE EFFECTIVENESS OF STATIC STRETCH AND HOLD RELAX TECHNIQUE OVER HAMSTRING FLEXIBILITY

    Directory of Open Access Journals (Sweden)

    Shanthi C

    2014-10-01

    Full Text Available Background: Numerous studies have documented on flexibility of muscles. Flexibility is defined as the ability of the muscles to lengthen allowing one joint or more than one joint in a series to move through a range of motion .Flexibility allows tissue to accommodate more easily to stress thus minimizing or preventing muscle injury. But this study sought to identify the study to compare the effectiveness of Static stretch and Hold relax technique over the hamstring flexibility. Methods: 30 healthy male adults with Hamstring tightness aged 21 to 35 years selected from general population through simple randomized technique. Samples are divided into two groups, static stretch Group-I(no.15 and Group-II Hold relax (no.=15.The outcome was measured with help of sit & reach test to see the Hamstring flexibility. Results: Comparison of the post test values of the group I and group II shows a significant difference between the outcomes of two groups with a “t” calculated value of 0.738 (unpaired “t” test. Conclusion: Both static stretch and hold relax Technique can cause very highly significant result in Hamstring Flexibility, further comparison shows very high significant difference between two groups and concludes that hold relax is better than static stretch in Hamstring Flexibility.

  16. Plantar fascia-specific stretching versus radial shock-wave therapy as initial treatment of plantar fasciopathy.

    Science.gov (United States)

    Rompe, Jan D; Cacchio, Angelo; Weil, Lowell; Furia, John P; Haist, Joachim; Reiners, Volker; Schmitz, Christoph; Maffulli, Nicola

    2010-11-03

    Whether plantar fascia-specific stretching or shock-wave therapy is effective as an initial treatment for proximal plantar fasciopathy remains unclear. The aim of this study was to test the null hypothesis of no difference in the effectiveness of these two forms of treatment for patients who had unilateral plantar fasciopathy for a maximum duration of six weeks and which had not been treated previously. One hundred and two patients with acute plantar fasciopathy were randomly assigned to perform an eight-week plantar fascia-specific stretching program (Group I, n = 54) or to receive repetitive low-energy radial shock-wave therapy without local anesthesia, administered weekly for three weeks (Group II, n = 48). All patients completed the seven-item pain subscale of the validated Foot Function Index and a patient-relevant outcome questionnaire. Patients were evaluated at baseline and at two, four, and fifteen months after baseline. The primary outcome measures were a mean change in the Foot Function Index sum score at two months after baseline, a mean change in item 2 (pain during the first few steps of walking in the morning) on this index, and satisfaction with treatment. No difference in mean age, sex, weight, or duration of symptoms was found between the groups at baseline. At two months after baseline, the Foot Function Index sum score showed significantly greater changes for the patients managed with plantar fascia-specific stretching than for those managed with shock-wave therapy (p plantar fascia is superior to repetitive low-energy radial shock-wave therapy for the treatment of acute symptoms of proximal plantar fasciopathy.

  17. Relationship between procrastination and academic performance among a group of undergraduate dental students in India.

    Science.gov (United States)

    Lakshminarayan, Nagesh; Potdar, Shrudha; Reddy, Siddana Goud

    2013-04-01

    Procrastination, generally defined as a voluntary, irrational delay of behavior, is a prevalent phenomenon among college students throughout the world and occurs at alarmingly high rates. For this study, a survey was conducted of 209 second-, third-, and fourth-year undergraduate dental students of Bapuji Dental College and Hospital, Davangere, India, to identify the relationship between their level of procrastination and academic performance. A sixteen-item questionnaire was used to assess the level of procrastination among these students. Data related to their academic performance were also collected. Spearman's correlation coefficient test was used to assess the relationship between procrastination and academic performance. It showed a negative correlation of -0.63 with a significance level of pprocrastination scores performed below average in their academics. In addition, analysis with the Mann-Whitney U test found a significant difference in procrastination scores between the two gender groups (pprocrastination and vice versa.

  18. [A study on breakfast and school performance in a group of adolescents].

    Science.gov (United States)

    Herrero Lozano, R; Fillat Ballesteros, J C

    2006-01-01

    TO know the relationship between breakfast, from a qualitative perspective, and school performance. The study was performed in 141 students (70 males and 71 females) with ages ranging 12-13 years, of 1st grade of Mandatory Secondary Education (ESO) from an institute of Saragossa, by means of recalling the breakfast of the day before. Breakfast quality has been assessed according to criteria of the Kid study: GOOD QUALITY: contains at least one food from each one of dairy, cereals, or fruit groups. IMPROVABLE QUALITY: lacks one of the groups. INSUFFICIENT QUALITY: lacks two groups. POOR QUALITY: does not have breakfast. We considered that quality was improved only when a mid-morning snack with a different food from those taken with breakfast was added. Average mark at the end of the school year has been the criterion used to assess school performance. Statistical analysis of data gathered for the present study has been done with SPSS software. This analysis comprises descriptive and inferential statistics. For analysis of global significance between the differences the Analysis of Variance method has been applied, followed by post hoe tests with Bonferroni's and Turkey's methods to detect specific groups explaining global significance. Average mark systematically increases as breakfast quality increases from an average score of 5.63 in the group with poor quality breakfast to 7.73 average score in the group with a good quality breakfast. An analysis of variance has been performed to study the statistical significance of the mean differences between both groups. The outcomes yield significant global differences between groups (p value = 0.001), i.e., the average mark significantly varies according to breakfast quality. When pooled quality of breakfast and mid-morning snack is analyzed, the average mark systematically increases as breakfast-snack quality increases, from an average mark of 5,77 in the group with poor or insufficient quality up to 7.61 in the group with

  19. Group music performance causes elevated pain thresholds and social bonding in small and large groups of singers

    Science.gov (United States)

    Weinstein, Daniel; Launay, Jacques; Pearce, Eiluned; Dunbar, Robin I. M.; Stewart, Lauren

    2016-01-01

    Over our evolutionary history, humans have faced the problem of how to create and maintain social bonds in progressively larger groups compared to those of our primate ancestors. Evidence from historical and anthropological records suggests that group music-making might act as a mechanism by which this large-scale social bonding could occur. While previous research has shown effects of music making on social bonds in small group contexts, the question of whether this effect ‘scales up’ to larger groups is particularly important when considering the potential role of music for large-scale social bonding. The current study recruited individuals from a community choir that met in both small (n = 20 – 80) and large (a ‘megachoir’ combining individuals from the smaller subchoirs n = 232) group contexts. Participants gave self-report measures (via a survey) of social bonding and had pain threshold measurements taken (as a proxy for endorphin release) before and after 90 minutes of singing. Results showed that feelings of inclusion, connectivity, positive affect, and measures of endorphin release all increased across singing rehearsals and that the influence of group singing was comparable for pain thresholds in the large versus small group context. Levels of social closeness were found to be greater at pre- and post-levels for the small choir condition. However, the large choir condition experienced a greater change in social closeness as compared to the small condition. The finding that singing together fosters social closeness – even in large contexts where individuals are not known to each other – is consistent with evolutionary accounts that emphasize the role of music in social bonding, particularly in the context of creating larger cohesive groups than other primates are able to manage. PMID:27158219

  20. Morphological, Physiological and Skating Performance Profiles of Male Age-Group Elite Ice Hockey Players.

    Science.gov (United States)

    Allisse, Maxime; Sercia, Pierre; Comtois, Alain-Steve; Leone, Mario

    2017-09-01

    The purpose of this study was to describe the evolution of morphological, physiological and skating performance profiles of elite age-group ice hockey players based on repeated measures spread over one season. In addition, the results of fitness tests and training programs performed in off-ice conditions and their relationship with skating performance were analyzed. Eighteen high level age-group ice hockey players (13.1 ± 0.6 years) were assessed off and on-ice at the beginning and at the end of the hockey season. A third evaluation was also conducted at the beginning of the following hockey season. The players were taller, heavier, and showed bone breadths and muscle girths above the reference population of the same age. Muscular variables improved significantly during and between the two hockey seasons (p skating performance tests exhibited significant enhancements during the hockey season, but not during the off-season where some degradation was observed. Finally, weak observed variances (generally skating performance tests indicated important gaps, both in the choice of the off-ice assessment tools as well as in training methods conventionally used. The reflection on the best way to assess and train hockey players certainly deserves to be continued.

  1. Morphological, Physiological and Skating Performance Profiles of Male Age-Group Elite Ice Hockey Players

    Directory of Open Access Journals (Sweden)

    Allisse Maxime

    2017-08-01

    Full Text Available The purpose of this study was to describe the evolution of morphological, physiological and skating performance profiles of elite age-group ice hockey players based on repeated measures spread over one season. In addition, the results of fitness tests and training programs performed in off-ice conditions and their relationship with skating performance were analyzed. Eighteen high level age-group ice hockey players (13.1 ± 0.6 years were assessed off and on-ice at the beginning and at the end of the hockey season. A third evaluation was also conducted at the beginning of the following hockey season. The players were taller, heavier, and showed bone breadths and muscle girths above the reference population of the same age. Muscular variables improved significantly during and between the two hockey seasons (p < 0.05. However, maximal aerobic power improved only during the off-season. All skating performance tests exhibited significant enhancements during the hockey season, but not during the off-season where some degradation was observed. Finally, weak observed variances (generally <20% of the explained variance between physiological variables measured off-ice and on-ice skating performance tests indicated important gaps, both in the choice of the off-ice assessment tools as well as in training methods conventionally used. The reflection on the best way to assess and train hockey players certainly deserves to be continued.

  2. Investigation of the Performance of Multidimensional Equating Procedures for Common-Item Nonequivalent Groups Design

    Directory of Open Access Journals (Sweden)

    Burcu ATAR

    2017-12-01

    Full Text Available In this study, the performance of the multidimensional extentions of Stocking-Lord, mean/mean, and mean/sigma equating procedures under common-item nonequivalent groups design was investigated. The performance of those three equating procedures was examined under the combination of various conditions including sample size, ability distribution, correlation between two dimensions, and percentage of anchor items in the test. Item parameter recovery was evaluated calculating RMSE (root man squared error and BIAS values. It was found that Stocking-Lord procedure provided the smaller RMSE and BIAS values for both item discrimination and item difficulty parameter estimates across most conditions.

  3. How Do Politicians Attribute Bureaucratic Responsibility for Performance? Negativity Bias and Interest Group Advocacy

    DEFF Research Database (Denmark)

    Nielsen, Poul A.; Moynihan, Donald P.

    2017-01-01

    Voters reward or punish politicians by deeming them responsible for positive and negative outcomes, but how, in turn, do politicians attribute responsibility to those who actually deliver public services? Inattention to this question renders incomplete current perspectives on democratic processes...... to attribute causal responsibility to bureaucratic leaders, but only in cases of low performance, suggesting a negativity bias in public sector responsibility attribution processes. Additionally, we offer evidence that interest group advocates influence how elected officials use performance information...... to attribute responsibility, but contingent on ideological alignment....

  4. An examination of the stretching practices of Division I and Division III college football programs in the midwestern United States.

    Science.gov (United States)

    Judge, Lawrence W; Craig, Bruce; Baudendistal, Steve; Bodey, Kimberly J

    2009-07-01

    Research supports the use of preactivity warm-up and stretching, and the purpose of this study was to determine whether college football programs follow these guidelines. Questionnaires designed to gather demographic, professional, and educational information, as well as specific pre- and postactivity practices, were distributed via e-mail to midwestern collegiate programs from NCAA Division I and III conferences. Twenty-three male coaches (12 from Division IA schools and 11 from Division III schools) participated in the study. Division I schools employed certified strength coaches (CSCS; 100%), whereas Division III schools used mainly strength coordinators (73%), with only 25% CSCS. All programs used preactivity warm-up, with the majority employing 2-5 minutes of sport-specific jogging/running drills. Pre stretching (5-10 minutes) was performed in 19 programs (91%), with 2 (9%) performing no pre stretching. Thirteen respondents used a combination of static/proprioceptive neuromuscular facilitation/ballistic and dynamic flexibility, 5 used only dynamic flexibility, and 1 used only static stretching. All 12 Division I coaches used stretching, whereas only 9 of the 11 Division III coaches did (p = 0.22). The results indicate that younger coaches did not use pre stretching (p = 0.30). The majority of the coaches indicated that they did use post stretching, with 11 of the 12 Division I coaches using stretching, whereas only 5 of the 11 Division III coaches used stretching postactivity (p = 0.027). Divisional results show that the majority of Division I coaches use static-style stretching (p = 0.049). The results of this study indicate that divisional status, age, and certification may influence how well research guidelines are followed. Further research is needed to delineate how these factors affect coaching decisions.

  5. Analysis of a Stretched Derivative Aircraft with Open Rotor Propulsion

    Science.gov (United States)

    Berton, Jeffrey J.; Hendricks, Eric S.; Haller, William J.; Guynn, Mark D.

    2015-01-01

    Research into advanced, high-speed civil turboprops received significant attention during the 1970s and 1980s when fuel efficiency was the driving focus of U.S. aeronautical research. But when fuel prices declined sharply there was no longer sufficient motivation to continue maturing the technology. Recent volatility in fuel prices and increasing concern for aviation's environmental impact, however, have renewed interest in unducted, open rotor propulsion and revived research by NASA and a number of engine manufacturers. Recently, NASA and General Electric have teamed to conduct several investigations into the performance and noise of an advanced, single-aisle transport with open rotor propulsion. The results of these initial studies indicate open rotor engines have the potential to provide significant reduction in fuel consumption compared to aircraft using turbofan engines with equivalent core technology. In addition, noise analysis of the concept indicates that an open rotor aircraft in the single-aisle transport class would be able to meet current noise regulations with margin. The behavior of derivative open rotor transports is of interest. Heavier, "stretched" derivative aircraft tend to be noisier than their lighter relatives. Of particular importance to the business case for the concept is how the noise margin changes relative to regulatory limits within a family of similar open rotor aircraft. The subject of this report is a performance and noise assessment of a notional, heavier, stretched derivative airplane equipped with throttle-push variants of NASA's initial open rotor engine design.

  6. The effect of streptomycin on stretch-induced electrophysiological changes of isolated acute myocardial infarcted hearts in rats.

    Science.gov (United States)

    Fu, Lu; Cao, Jun-xian; Xie, Rong-sheng; Li, Jia; Han, Ying; Zhu, Li-qun; Dai, Ying-nan

    2007-08-01

    To explore whether the stretch of ischaemic myocardium could modulate the electrophysiological characteristics, especially repolarization via mechanoelectric feedback (MEF), as well as the effect of streptomycin (SM) on these changes. Methods Thirty-six wistar rats were randomly divided into four groups: control group (n = 9), SM group (n = 9), myocardial infarction (MI) group (n = 9), and MI + SM group (n = 9). After perfused on Langendorff, the isolated hearts were stretched for 5s by a ballon inflation of 0.2mL. After being stretched, the effect of the stretch was observed for 30s, including the 20, 20-70, 70, and 90% monophasic action potential duration (MAPD), i.e. MAPD(20), MAPD(20-70), MAPD(70), and MAPD(90), respectively, premature ventricular beats (PVB), and ventricular tachycardia (VT). Results The stretch caused a decrease in MAPD(20-70) (both P 0.05, except MAPD(20-70) between the control and SM groups, P maintenance of malignant arrhythmias. SM could significantly inhibit the occurrence of arrhythmias, which may correlate with the effect on blocking stretch-activated ion channels.

  7. Interactive performance and focus groups with adolescents: the power of play.

    Science.gov (United States)

    Norris, Anne E; Aroian, Karen J; Warren, Stefanie; Wirth, Jeff

    2012-12-01

    Conducting focus groups with adolescents can be challenging given their developmental needs, particularly with sensitive topics. These challenges include intense need for peer approval, declining social trust, short attention span, and reliance on concrete operations thinking. In this article, we describe an adaptation of interactive performance as an alternative to traditional focus group method. We used this method in a study of discrimination experienced by Muslims (ages 13-17) and of peer pressure to engage in sexual behavior experienced by Hispanic girls (ages 10-14). Recommendations for use of this method include using an interdisciplinary team, planning for large amounts of disclosure towards the end of the focus group, and considering the fit of this method to the study topic. Copyright © 2012 Wiley Periodicals, Inc.

  8. Charge transfer through amino groups-small molecules interface improving the performance of electroluminescent devices

    Science.gov (United States)

    Havare, Ali Kemal; Can, Mustafa; Tozlu, Cem; Kus, Mahmut; Okur, Salih; Demic, Şerafettin; Demirak, Kadir; Kurt, Mustafa; Icli, Sıddık

    2016-05-01

    A carboxylic group functioned charge transporting was synthesized and self-assembled on an indium tin oxide (ITO) anode. A typical electroluminescent device [modified ITO/TPD (50 nm)/Alq3 (60 nm)/LiF (2 nm)/(120 nm)] was fabricated to investigate the effect of the amino groups-small molecules interface on the characteristics of the device. The increase in the surface work function of ITO is expected to facilitate the hole injection from the ITO anode to the Hole Transport Layer (HTL) in electroluminescence. The modified electroluminescent device could endure a higher current and showed a much higher luminance than the nonmodified one. For the produced electroluminescent devices, the I-V characteristics, optical characterization and quantum yields were performed. The external quantum efficiency of the modified electroluminescent device is improved as the result of the presence of the amino groups-small molecules interface.

  9. The Analysis Performance Method Naive Bayes Andssvm Determine Pattern Groups of Disease

    Science.gov (United States)

    Sitanggang, Rianto; Tulus; Situmorang, Zakarias

    2017-12-01

    Information is a very important element and into the daily needs of the moment, to get a precise and accurate information is not easy, this research can help decision makers and make a comparison. Researchers perform data mining techniques to analyze the performance of methods and algorithms naïve Bayes methods Smooth Support Vector Machine (ssvm) in the grouping of the disease.The pattern of disease that is often suffered by people in the group can be in the detection area of the collection of information contained in the medical record. Medical records have infromasi disease by patients in coded according to standard WHO. Processing of medical record data to find patterns of this group of diseases that often occur in this community take the attribute address, sex, type of disease, and age. Determining the next analysis is grouping of four ersebut attribute. From the results of research conducted on the dataset fever diabete mellitus, naïve Bayes method produces an average value of 99% and an accuracy and SSVM method produces an average value of 93% accuracy

  10. Differences in morphological parameters of judo athletes of different age groups and performance level

    Directory of Open Access Journals (Sweden)

    Miloš Štefanovský

    2017-12-01

    Full Text Available Background: Some studies have pointed out the influence of morphological parameters on judo performance, however the relationship between morphological variables and performance status have not yet been confirmed. In addition, there is a lack of studies focused on morphological comparison of different age categories. Objective: The aim of this study was to assess differences in the morphological parameters of judo athletes of different age and performance level. Methods: The research sample was composed of 47 male judokas (age 19.15 ± 2.93 years; body weight 77.16 ± 11.39 kg; height 178.91 ± 6.39 cm; sport age 11.47 ± 2.74 years. It was divided by: (1 age, into cadets (15-17 years, n = 19, juniors (18-20 years, n = 15, and seniors (21+ years, n = 13 category and (2 performance status (elite, n = 10; non-elite, n = 37. In all participants, body fat, and the circumference measurement of wrist, forearm, flexed arm, and calf were observed. A personal interview was used to gain information about the athlete's performance status. Results: We found out that there are significant differences in arm circumference between cadets and seniors, cadets and juniors, juniors and seniors; and in the circumference of forearm between cadets and seniors; cadets and juniors, as well. According to the performance status, we have discovered significantly higher circumference of forearm and wrist in the elite group compared to the non-elite group. Conclusion: Forearm and wrist circumference is a reliable discriminative factor and should be taken into consideration, especially when selecting judo athletes into elite teams. However, we did not confirm that subcutaneous fat is a parameter able to distinguish between judo athletes of different performance status across various age categories.

  11. Relationship between physical activity and physical performance in later life in different birth weight groups.

    Science.gov (United States)

    Jantunen, H; Wasenius, N S; Salonen, M K; Perälä, M-M; Kautiainen, H; Simonen, M; Pohjolainen, P; Kajantie, E; von Bonsdorff, M B; Eriksson, J G

    2018-02-01

    There is strong evidence that physical activity (PA) has an influence on physical performance in later life. Also, a small body size at birth has been associated with lower physical functioning in older age and both small and high birth weight have shown to be associated with lower leisure time physical activity. However, it is unknown whether size at birth modulates the association between PA and physical performance in old age. We examined 695 individuals from the Helsinki Birth Cohort Study born in Helsinki, Finland between 1934 and 1944. At a mean age of 70.7 years PA was objectively assessed with a multisensory activity monitor and physical performance with the Senior Fitness Test (SFT). Information on birth weight and gestational age was retrieved from hospital birth records. The study participants were divided in three birth weight groups, that is birth weight groups. However, the effect size of the association was large and significant only in men with a birth weight confidence interval 0.37-0.81, Pbirth weight. Our results suggest that men with low birth weight might benefit most from engaging in PA in order to maintain a better physical performance.

  12. A control scheme for filament stretching rheometers with application to polymer melts

    DEFF Research Database (Denmark)

    Román Marín, José Manuel; Huusom, Jakob Kjøbsted; Javier Alvarez, Nicolas

    2013-01-01

    We propose a new control scheme to maintain a constant strain rate of the mid-filament diameter in a filament stretching rheometer for polymer melts. The scheme is cast as a velocity algorithm and consists of a feed-back and a feed-forward contribution. The performance of the controller is demons......We propose a new control scheme to maintain a constant strain rate of the mid-filament diameter in a filament stretching rheometer for polymer melts. The scheme is cast as a velocity algorithm and consists of a feed-back and a feed-forward contribution. The performance of the controller...

  13. COMPARISON OF EFFECTS OF ABDOMINAL STRETCHING EXERCISE AND COLD COMPRESS THERAPY ON MENSTRUAL PAIN INTENSITY IN TEENAGE GIRLS

    Directory of Open Access Journals (Sweden)

    Desta Ayu Cahya Rosyida

    2017-07-01

    Full Text Available Background: Pain during menstruation is not uncommon, especially in young women, which has an impact on their life activities. Objective: To examine the effect of abdominal stretching exercise and cold compress therapy on decreasing intensity of menstrual pain in teenage girls at SMK Bakti Indonesia Medika. Design: A Quasy Experimental Study with two group comparison pretest-postest design. There were 46 respondents selected in this study by consecutive sampling that consisted of 23 samples in the abdominal stretching exercise group and 23 samples in the cold compress group. The menstrual pain was measured using VAS (visual analog scale. Data were analyzed using Mann-Whitney, Chi-Square, and Wilcoxon test. Results: Findings showed that the mean of menstrual pain before intervention in the abdominal stretching exercise was 7.04 and in the cold compress therapy was 6.74 with p-value 0.211 (<0.05, which indicated that there was no mean difference of pain between both groups. However, after intervention, the menstrual pain was reduced from 7.04 to 1.91 (5.09 difference in the abdominal stretching exercise group; and from 6.74 to 5.52 (1.22 difference in the cold compress group with p-value 0.000 (<0.05, which indicated that there was statistically significant difference of menstrual pain before and after intervention, both abdominal stretching exercise and cold compress therapy. Conclusion: There were statistically significant effects of abdominal stretching exercise and cold compress therapy on menstrual pain in teenage girls. The abdominal stretching exercise is more effective than cold compress therapy in reducing menstrual pain intensity. Thus, it is suggested that abdominal stretching exercise can be an alternative choice of management of dysmenorrhea in teenage girls, and can be a part of subject in the education as non-pharmacological medicine.

  14. To Stretch and Search for Better Ways

    Science.gov (United States)

    Moore, John W.

    2000-06-01

    There's a lot to do to get each issue of this Journal ready for publication, and there's a lot that can go awry during that process. We the editorial staff do our utmost to make certain that each issue is the best it can possibly be, but, of necessity, a lot of our effort is focused on solving problems, correcting errors, and avoiding pitfalls. It is not surprising that we sometimes lose sight of the bigger picture--all of the things that came out as well as or better than we hoped they would. Therefore it gives us great pleasure when a reader applauds (and thereby rewards) our efforts. One such communication inspired this editorial. I have appreciated the extra effort put forward by the staff to make the Journal really come alive. The high quality of the Journal serves as an incentive to chemical educators to stretch and search for better ways to inspire our students. I fervently hope that we do encourage you "to stretch and search for better ways", not only to inspire students but in everything you do. Stretching and searching for better ways is what life, science, chemistry, and teaching are all about, and it is a wonderfully stimulating and exciting way to approach anything and everything. Sometimes, though, one's ability to stretch is akin to that of a rubber band exposed too long to sunlight. Change becomes a threat or a burden instead of an opportunity. This often happens in one area but not others, as in the case of someone doing original research but whose lecture notes are yellow with age, or someone who experiments with new teaching approaches but neglects the latest chemical discoveries. Whatever its manifestation, failure to stretch and search for better ways is a great loss, both for the individual directly involved and for others. Fortunately there are many who continually stretch and search, often in conjunction with JCE. For example, some time ago the Chair of the Board of Publication, Jerry Bell, challenged Journal readers to become Journal

  15. Stretched horizons, quasiparticles, and quasinormal modes

    International Nuclear Information System (INIS)

    Iizuka, Norihiro; Kabat, Daniel; Lifschytz, Gilad; Lowe, David A.

    2003-01-01

    We propose that stretched horizons can be described in terms of a gas of noninteracting quasiparticles. The quasiparticles are unstable, with a lifetime set by the imaginary part of the lowest quasinormal mode frequency. If the horizon arises from an AdS-CFT style duality the quasiparticles are also the effective low-energy degrees of freedom of the finite-temperature CFT. We analyze a large class of models including Schwarzschild black holes, nonextremal Dp-branes, the rotating BTZ black hole and de Sitter space, and we comment on degenerate horizons. The quasiparticle description makes manifest the relationship between entropy and area

  16. Viscous flows stretching and shrinking of surfaces

    CERN Document Server

    Mehmood, Ahmer

    2017-01-01

    This authored monograph provides a detailed discussion of the boundary layer flow due to a moving plate. The topical focus lies on the 2- and 3-dimensional case, considering axially symmetric and unsteady flows. The author derives a criterion for the self-similar and non-similar flow, and the turbulent flow due to a stretching or shrinking sheet is also discussed. The target audience primarily comprises research experts in the field of boundary layer flow, but the book will also be beneficial for graduate students.

  17. Bias of purine stretches in sequenced chromosomes

    DEFF Research Database (Denmark)

    Ussery, David; Soumpasis, Dikeos Mario; Brunak, Søren

    2002-01-01

    /pur tracts was slightly less than expected, with an average of 0.8%. One of the most surprising findings is a clear difference in the length distributions of the regions studied between prokaryotes and eukaryotes. Whereas short-range correlations can explain the length distributions in prokaryotes......, in eukaryotes there is an abundance of long stretches of purines or alternating purine/pyrimidine tracts, which cannot be explained in this way; these sequences are likely to play an important role in eukaryotic chromosome organisation....

  18. Prolonged passive static stretching-induced innervation zone shift in biceps brachii.

    Science.gov (United States)

    Ye, Xin; Beck, Travis W; Wages, Nathan P

    2015-05-01

    The purpose of this study was to examine the influence of a bout of repeated and prolonged passive static stretching on the innervation zone (IZ) location of the human biceps brachii muscle. Eleven men performed 12 sets of 100-s passive stretches on their biceps brachii. Before (Pre) and immediately after (Post) the stretching intervention, isometric strength was tested during the maximal voluntary contractions (MVCs) of the forearm flexors. The subjects also performed several separate isometric forearm flexion muscle actions at 30%, 50%, and 70% of their predetermined MVCs for examining the locations of the IZ at different contraction intensities. The IZ was identified through multi-channel surface electromyographic (EMG) recordings from a linear electrode array. The stretching intervention induced an average of 10% isometric strength loss for the forearm flexors (mean±SD: Pre-MVC vs. Post-MVC=332.12±59.40 N vs. 299.53±70.51 N; p<0.001). In addition, the average IZ shift was nearly 4.5 mm in average in the proximal direction. However, this shift was not specific to the contraction intensity. We believe that the IZ shift was caused by the elongation of the entire muscle-tendon unit in the proximal direction. Therefore, caution should be taken when using surface EMG technique to examine possible changes in the EMG variables after a stretching protocol, as these variables can be contaminated by the shift of the IZ.

  19. Stretches of alternating pyrimidine/purines and purines are respectively linked with pathogenicity and growth temperature in prokaryotes

    DEFF Research Database (Denmark)

    Ussery, David; Bohlin, J; Hardy, SP

    2009-01-01

    BACKGROUND: The genomic fractions of purine (RR) and alternating pyrimidine/purine (YR) stretches of 10 base pairs or more, have been linked to genomic AT content, the formation of different DNA helices, strand-biased gene distribution, DNA structure, and more. Although some of these factors are ...... phyla. RR stretches are overrepresented in all phyla except for the Actinobacteria and beta-Proteobacteria. In contrast, YR tracts are underrepresented in all phyla except for the beta-Proteobacterial group. YR-stretches are associated with phylum, pathogenicity and habitat, whilst RR...

  20. Effects of Bed Rest on Conduction Velocity of the Triceps Surae Stretch Reflex and Postural Control

    Science.gov (United States)

    Reschke, M. F.; Wood, S. J.; Cerisano, J. M.; Kofman, I. S.; Fisher, E. A.; Esteves, J. T.; Taylor, L. C.; DeDios, Y. E.; Harm, D. L.

    2011-01-01

    Despite rigorous exercise and nutritional management during space missions, astronauts returning from microgravity exhibit neuromuscular deficits and a significant loss in muscle mass in the postural muscles of the lower leg. Similar changes in the postural muscles occur in subjects participating in long-duration bed rest studies. These adaptive muscle changes manifest as a reduction in reflex conduction velocity during head-down bed rest. Because the stretch reflex encompasses both the peripheral (muscle spindle and nerve axon) and central (spinal synapse) components involved in adaptation to calf muscle unloading, it may be used to provide feedback on the general condition of neuromuscular function, and might be used to evaluate the effectiveness of countermeasures aimed at preserving muscle mass and function during periods of unloading. Stretch reflexes were measured on 18 control subjects who spent 60 to 90 days in continuous 6 deg head-down bed rest. Using a motorized system capable of rotating the foot around the ankle joint (dorsiflexion) through an angle of 10 degrees at a peak velocity of about 250 deg/sec, a stretch reflex was recorded from the subject's left triceps surae muscle group. Using surface electromyography, about 300 reflex responses were obtained and ensemble-averaged on 3 separate days before bed rest, 3 to 4 times in bed, and 3 times after bed rest. The averaged responses for each test day were examined for reflex latency and conduction velocity (CV) across gender. Computerized posturography was also conducted on these same subjects before and after bed rest as part of the standard measures. Peak-to-peak sway was measured during Sensory Organization Tests (SOTs) to evaluate changes in the ability to effectively use or suppress visual, vestibular, and proprioceptive information for postural control. Although no gender differences were found, a significant increase in reflex latency and a significant decrease in CV were observed during the bed

  1. Mindfulness Training Improves Attentional Task Performance in Incarcerated Youth: A Group Randomized Controlled Intervention Trial

    Directory of Open Access Journals (Sweden)

    Noelle R Leonard

    2013-11-01

    Full Text Available We investigated the impact of cognitive behavioral therapy and mindfulness training (CBT/MT on attentional task performance in incarcerated adolescents. Attention is a cognitive system necessary for managing cognitive demands and regulating emotions. Yet persistent and intensive demands, such as those experienced during high-stress intervals like incarceration and the events leading to incarceration, may deplete attention resulting in cognitive failures, emotional disturbances, and impulsive behavior. We hypothesized that CBT/MT may mitigate these deleterious effects of high stress and protect against degradation in attention over the high-stress interval of incarceration. Using a group randomized controlled trial design, we randomly assigned dormitories of incarcerated youth, ages 16 to 18, to a CBT/MT intervention (youth n = 147 or an active control intervention (youth n = 117. Both arms received approximately 750 minutes of intervention in a small-group setting over a 3-5 week period. Youth in the CBT/MT arm also logged the amount of out-of-session time spent practicing MT exercises. The Attention Network Test was used to index attentional task performance at baseline and 4 months post-baseline. Overall, task performance degraded over time in all participants. The magnitude of performance degradation was significantly less in the CBT/MT vs. control arm. Further, within the CBT/MT arm, performance degraded over time in those with no outside-of-class practice time, but remained stable over time in those who practiced mindfulness exercises outside of the session meetings. Thus, these findings suggest that sufficient CBT/MT practice may protect against functional attentional impairments associated with high-stress intervals. Keywords: adolescent development, incarcerated adolescents, detained adolescents, stress, attention, mindfulness meditation.

  2. Effects of incentives on psychosocial performances in simulated space-dwelling groups

    Science.gov (United States)

    Hienz, Robert D.; Brady, Joseph V.; Hursh, Steven R.; Gasior, Eric D.; Spence, Kevin R.; Emurian, Henry H.

    Prior research with individually isolated 3-person crews in a distributed, interactive, planetary exploration simulation examined the effects of communication constraints and crew configuration changes on crew performance and psychosocial self-report measures. The present report extends these findings to a model of performance maintenance that operationalizes conditions under which disruptive affective responses by crew participants might be anticipated to emerge. Experiments evaluated the effects of changes in incentive conditions on crew performance and self-report measures in simulated space-dwelling groups. Crews participated in a simulated planetary exploration mission that required identification, collection, and analysis of geologic samples. Results showed that crew performance effectiveness was unaffected by either positive or negative incentive conditions, while self-report measures were differentially affected—negative incentive conditions produced pronounced increases in negative self-report ratings and decreases in positive self-report ratings, while positive incentive conditions produced increased positive self-report ratings only. Thus, incentive conditions associated with simulated spaceflight missions can significantly affect psychosocial adaptation without compromising task performance effectiveness in trained and experienced crews.

  3. Occupational performance characteristics of a group of adults with HIV-AIDS

    Directory of Open Access Journals (Sweden)

    Angélica María Monsalve Robayo

    2017-03-01

    Full Text Available Introduction: The human immunodeficiency virus affects the lives of people especially regarding self-care, work and leisure time, factors that compromise the exercise of social participation. Objective: To describe the occupational performance of 29 patients living with HIV and AIDS assisted by the B24 program in a hospital in Bogotá-Colombia. Method: Descriptive and exploratory study on patterns of performance, occupational roles and independence in instrumental activities of daily living (IADL. An interview was conducted and an occupational questionnaire, the Lawton and Brody index, was used. Data were processed in SPSS and frequency analysis was performed. Results: Participants were 53 years old in average, 82.8% were men and 48.3% had higher education. They work an average of 2 hours a day and spend 11 hours a day with daily activities, and almost 5 or 6 hours with leisure and rest. The most significant roles are friend and family member, and the least significant, member of religious groups. Among participants, 65.5% are independent to develop IADL, 31% need help for some activities and 3.4% is dependent. Signs and symptoms of HIV and opportunistic infections make it difficult to assume roles, including work activities. Conclusion: Cobra value demonstrates the meaning of occupational transition for this group and its future perspective to implement programs that may foster the importance of their social and family participation.

  4. What Factors Influence Well-being of Students on Performing Small Group Discussion?

    Science.gov (United States)

    Wulanyani, N. M. S.; Vembriati, N.

    2018-01-01

    Generally, Faculty of Medicine of Udayana University applied Small Group Discussion (SGD) in its learning process. If group problem solving succeeds, each individual of the group will individually succeed. However, the success is also determined by each individual’s level of psychological well-being. When the students are in the high level of wellbeing, they will feel comfortable in small group discussion, and teamwork will be effective. Therefore, it is needed to conduct a research which investigates how psychological factors, such as traits, needs, cognitive, and social intelligence, influence students’ wellbeing in performing SGD. This research is also initiated by several cases of students who prefer individual learning and take SGD merely to fulfill attendance requirement. If the students have good wellbeing, they will take the SGD process optimally. The subject of this research was 100 students of Faculty of Medicine of Udayana University. This survey research used psychological test assessment, Psychological well-being scale, and Social Intelligence scale to gain data analyzed quantitatively. The results showed that all aspects of traits together with aspects ‘need for rules and supervision’ affect social intelligence. Furthermore, social intelligence factor with cognitive factors influence wellbeing of the students in the process of SGD.

  5. Twist-stretch profiles of DNA chains

    Science.gov (United States)

    Zoli, Marco

    2017-06-01

    Helical molecules change their twist number under the effect of a mechanical load. We study the twist-stretch relation for a set of short DNA molecules modeled by a mesoscopic Hamiltonian. Finite temperature path integral techniques are applied to generate a large ensemble of possible configurations for the base pairs of the sequence. The model also accounts for the bending and twisting fluctuations between adjacent base pairs along the molecules stack. Simulating a broad range of twisting conformation, we compute the helix structural parameters by averaging over the ensemble of base pairs configurations. The method selects, for any applied force, the average twist angle which minimizes the molecule’s free energy. It is found that the chains generally over-twist under an applied stretching and the over-twisting is physically associated to the contraction of the average helix diameter, i.e. to the damping of the base pair fluctuations. Instead, assuming that the maximum amplitude of the bending fluctuations may decrease against the external load, the DNA molecule first over-twists for weak applied forces and then untwists above a characteristic force value. Our results are discussed in relation to available experimental information albeit for kilo-base long molecules.

  6. Stretched Exponential relaxation in pure Se glass

    Science.gov (United States)

    Dash, S.; Ravindren, S.; Boolchand, P.

    A universal feature of glasses is the stretched exponential relaxation, f (t) = exp[ - t / τ ] β . The model of diffusion of excitations to randomly distributed traps in a glass by Phillips1 yields the stretched exponent β = d[d +2] where d, the effective dimensionality. We have measured the enthalpy of relaxation ΔHnr (tw) at Tg of Se glass in modulated DSC experiments as glasses age at 300K and find β = 0.43(2) for tw in the 0

  7. Stretch sensors for human body motion

    Science.gov (United States)

    O'Brien, Ben; Gisby, Todd; Anderson, Iain A.

    2014-03-01

    Sensing motion of the human body is a difficult task. From an engineers' perspective people are soft highly mobile objects that move in and out of complex environments. As well as the technical challenge of sensing, concepts such as comfort, social intrusion, usability, and aesthetics are paramount in determining whether someone will adopt a sensing solution or not. At the same time the demands for human body motion sensing are growing fast. Athletes want feedback on posture and technique, consumers need new ways to interact with augmented reality devices, and healthcare providers wish to track recovery of a patient. Dielectric elastomer stretch sensors are ideal for bridging this gap. They are soft, flexible, and precise. They are low power, lightweight, and can be easily mounted on the body or embedded into clothing. From a commercialisation point of view stretch sensing is easier than actuation or generation - such sensors can be low voltage and integrated with conventional microelectronics. This paper takes a birds-eye view of the use of these sensors to measure human body motion. A holistic description of sensor operation and guidelines for sensor design will be presented to help technologists and developers in the space.

  8. Curved Piezoelectric Actuators for Stretching Optical Fibers

    Science.gov (United States)

    Allison, Sidney G.; Shams, Qamar A.; Fox, Robert L.

    2008-01-01

    Assemblies containing curved piezoceramic fiber composite actuators have been invented as means of stretching optical fibers by amounts that depend on applied drive voltages. Piezoceramic fiber composite actuators are conventionally manufactured as sheets or ribbons that are flat and flexible, but can be made curved to obtain load-carrying ability and displacement greater than those obtainable from the flat versions. In the primary embodiment of this invention, piezoceramic fibers are oriented parallel to the direction of longitudinal displacement of the actuators so that application of drive voltage causes the actuator to flatten, producing maximum motion. Actuator motion can be transmitted to the optical fiber by use of hinges and clamp blocks. In the original application of this invention, the optical fiber contains a Bragg grating and the purpose of the controlled stretching of the fiber is to tune the grating as part of a small, lightweight, mode-hop-free, rapidly tunable laser for demodulating strain in Bragg-grating strain-measurement optical fibers attached to structures. The invention could also be used to apply controllable tensile force or displacement to an object other than an optical fiber.

  9. Somatic, Endurance Performance and Heart Rate Variability Profiles of Professional Soccer Players Grouped According to Age

    Directory of Open Access Journals (Sweden)

    Botek Michal

    2016-12-01

    Full Text Available This cross-sectional study compared somatic, endurance performance determinants and heart rate variability (HRV profiles of professional soccer players divided into different age groups: GI (17–19.9 years; n = 23, GII (20–24.9 years; n = 45, GIII (25–29.9 years; n = 30, and GIV (30–39 years; n = 26. Players underwent somatic and HRV assessment and maximal exercise testing. HRV was analyzed by spectral analysis of HRV, and high (HF and low (LF frequency power was transformed by a natural logarithm (Ln. Players in GIV (83 ± 7 kg were heavier (p 25 years showed negligible differences in Pmax unlike the age group differences demonstrated in VO2max. A shift towards relative sympathetic dominance, particularly due to reduced vagal activity, was apparent after approximately 8 years of competing at the professional level.

  10. Mechanical response of human female breast skin under uniaxial stretching.

    Science.gov (United States)

    Kumaraswamy, N; Khatam, Hamed; Reece, Gregory P; Fingeret, Michelle C; Markey, Mia K; Ravi-Chandar, Krishnaswamy

    2017-10-01

    Skin is a complex material covering the entire surface of the human body. Studying the mechanical properties of skin to calibrate a constitutive model is of great importance to many applications such as plastic or cosmetic surgery and treatment of skin-based diseases like decubitus ulcers. The main objective of the present study was to identify and calibrate an appropriate material constitutive model for skin and establish certain universal properties that are independent of patient-specific variability. We performed uniaxial tests performed on breast skin specimens freshly harvested during mastectomy. Two different constitutive models - one phenomenological and another microstructurally inspired - were used to interpret the mechanical responses observed in the experiments. Remarkably, we found that the model parameters that characterize dependence on previous maximum stretch (or preconditioning) exhibited specimen-independent universal behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Fluid forces enhance the performance of an aspirant leader in self-organized living groups.

    Directory of Open Access Journals (Sweden)

    Alessandro De Rosis

    Full Text Available In this paper, the performance of an individual aiming at guiding a self-organized group is numerically investigated. A collective behavioural model is adopted, accounting for the mutual repulsion, attraction and orientation experienced by the individuals. Moreover, these represent a set of solid particles which are supposed to be immersed in a fictitious viscous fluid. In particular, the lattice Boltzmann and Immersed boundary methods are used to predict the fluid dynamics, whereas the effect of the hydrodynamic forces on particles is accounted for by solving the equation of the solid motion through the time discontinuous Galerkin scheme. Numerical simulations are carried out by involving the individuals in a dichotomous process. On the one hand, an aspirant leader (AL additional individual is added to the system. AL is forced to move along a prescribed direction which intersects the group. On the other hand, these tend to depart from an obstacle represented by a rotating lamina which is placed in the fluid domain. A numerical campaign is carried out by varying the fluid viscosity and, as a consequence, the hydrodynamic field. Moreover, scenarios characterized by different values of the size of the group are investigated. In order to estimate the AL's performance, a proper parameter is introduced, depending on the number of individuals following AL. Present findings show that the sole collective behavioural equations are insufficient to predict the AL's performance, since the motion is drastically affected by the presence of the surrounding fluid. With respect to the existing literature, the proposed numerical model is enriched by accounting for the presence of the encompassing fluid, thus computing the hydrodynamic forces arising when the individuals move.

  12. Effective grouping for energy and performance: Construction of adaptive, sustainable, and maintainable data storage

    Science.gov (United States)

    Essary, David S.

    The performance gap between processors and storage systems has been increasingly critical over the years. Yet the performance disparity remains, and further, storage energy consumption is rapidly becoming a new critical problem. While smarter caching and predictive techniques do much to alleviate this disparity, the problem persists, and data storage remains a growing contributor to latency and energy consumption. Attempts have been made at data layout maintenance, or intelligent physical placement of data, yet in practice, basic heuristics remain predominant. Problems that early studies sought to solve via layout strategies were proven to be NP-Hard, and data layout maintenance today remains more art than science. With unknown potential and a domain inherently full of uncertainty, layout maintenance persists as an area largely untapped by modern systems. But uncertainty in workloads does not imply randomness; access patterns have exhibited repeatable, stable behavior. Predictive information can be gathered, analyzed, and exploited to improve data layouts. Our goal is a dynamic, robust, sustainable predictive engine, aimed at improving existing layouts by replicating data at the storage device level. We present a comprehensive discussion of the design and construction of such a predictive engine, including workload evaluation, where we present and evaluate classical workloads as well as our own highly detailed traces collected over an extended period. We demonstrate significant gains through an initial static grouping mechanism, and compare against an optimal grouping method of our own construction, and further show significant improvement over competing techniques. We also explore and illustrate the challenges faced when moving from static to dynamic (i.e. online) grouping, and provide motivation and solutions for addressing these challenges. These challenges include metadata storage, appropriate predictive collocation, online performance, and physical placement

  13. Simulating the service life performance of an inspected group of jacket-type structures

    DEFF Research Database (Denmark)

    Schneider, Ronald; Thöns, Sebastian; Rogge, Andreas

    2017-01-01

    and risk. We intend to adopt this approach to optimize inspection, monitoring and repair activities for offshore wind park support structures. As a first step, we simulate – in analogy to an offshore wind park – the service life performance of an inspected group of jacket-type frames. The performance......A novel method for risk-based optimization of inspection and repair strategies for deteriorating structural systems has recently been proposed. The method defines heuristics at the system level to reduce the number of possible strategies. For each defined strategy, it computes the updated system...... failure probability conditional on simulated inspection and repair histories, and evaluates the associated costs and risk. The expected total service life costs and risk for a strategy are finally determined using Monte Carlo simulation. The optimal strategy minimizes the expected total service life costs...

  14. Magnetohydrodynamics Carreau nanofluid flow over an inclined convective heated stretching cylinder with Joule heating

    Directory of Open Access Journals (Sweden)

    Imad Khan

    Full Text Available Current work highlights the computational aspects of MHD Carreau nanofluid flow over an inclined stretching cylinder with convective boundary conditions and Joule heating. The mathematical modeling of physical problem yields nonlinear set of partial differential equations. A suitable scaling group of variables is employed on modeled equations to convert them into non-dimensional form. The integration scheme Runge-Kutta-Fehlberg on the behalf of shooting technique is utilized to solve attained set of equations. The interesting aspects of physical problem (linear momentum, energy and nanoparticles concentration are elaborated under the different parametric conditions through graphical and tabular manners. Additionally, the quantities (local skin friction coefficient, local Nusselt number and local Sherwood number which are responsible to dig out the physical phenomena in the vicinity of stretched surface are computed and delineated by varying controlling flow parameters. Keywords: MHD, Carreau nanofluid, Inclined stretching cylinder, Joule heating, Shooting technique

  15. Short-term pressure induced suppression of the short-latency response: a new methodology for investigating stretch reflexes

    DEFF Research Database (Denmark)

    Leukel, Christian; Lundbye-Jensen, Jesper; Gruber, Markus

    2009-01-01

    During experiments involving ischemic nerve block, we noticed that the short-latency response (SLR) of evoked stretches in m. soleus decreased immediately following inflation of a pneumatic cuff surrounding the lower leg. The present study aimed to investigate this short-term effect of pressure......) were recorded. Additionally, stretches were applied with different velocities and amplitudes. Finally, the SLR was investigated during hopping and in two protocols that modified the ability of the muscle-tendon complex distal to the cuff to stretch. All measurements were performed with deflated...

  16. An Allegory of Addiction Recovery: Exploring the Performance of "Eumenides" by Aeschylus, as Adapted by 18 ANO Theatre Group

    Science.gov (United States)

    Zontou, Zoe

    2013-01-01

    This paper examines the performance of the "Eumenides," as adapted and performed by 18 ANO theatre group. 18 ANO is the theatre group of the Drug dependence treatment unit 18 ANO of Attica's Psychiatric Hospital, which is based in Athens, Greece. Each year 18 ANO organises performances in the wider community with the aim of promoting…

  17. Influence of platinum group metal-free catalyst synthesis on microbial fuel cell performance

    Science.gov (United States)

    Santoro, Carlo; Rojas-Carbonell, Santiago; Awais, Roxanne; Gokhale, Rohan; Kodali, Mounika; Serov, Alexey; Artyushkova, Kateryna; Atanassov, Plamen

    2018-01-01

    Platinum group metal-free (PGM-free) ORR catalysts from the Fe-N-C family were synthesized using sacrificial support method (SSM) technique. Six experimental steps were used during the synthesis: 1) mixing the precursor, the metal salt, and the silica template; 2) first pyrolysis in hydrogen rich atmosphere; 3) ball milling; 4) etching the silica template using harsh acids environment; 5) the second pyrolysis in ammonia rich atmosphere; 6) final ball milling. Three independent batches were fabricated following the same procedure. The effect of each synthetic parameters on the surface chemistry and the electrocatalytic performance in neutral media was studied. Rotating ring disk electrode (RRDE) experiment showed an increase in half wave potential and limiting current after the pyrolysis steps. The additional improvement was observed after etching and performing the second pyrolysis. A similar trend was seen in microbial fuel cells (MFCs), in which the power output increased from 167 ± 2 μW cm-2 to 214 ± 5 μW cm-2. X-ray Photoelectron Spectroscopy (XPS) was used to evaluate surface chemistry of catalysts obtained after each synthetic step. The changes in chemical composition were directly correlated with the improvements in performance. We report outstanding reproducibility in both composition and performance among the three different batches.

  18. Oral health and school performance in a group of schoolchildren from the Federal District, Brazil.

    Science.gov (United States)

    Almeida, Raquel Francis; Leal, Soraya Coelho; Medonca, Jordana Guedes Amorim; Hilgert, Leandro Augusto; Ribeiro, Ana Paula Dias

    2018-05-12

    To evaluate whether an association exists between school performance, quality of life, dental caries, and dental pain in children between 6 and 8 years of age. All 6- to 8-year-old children enrolled in the second year of the six public schools in Paranoá-FD were invited to participate in this cross-sectional study. In total, 374 consented. Dental caries was recorded according to the Caries Assessment Spectrum and Treatment (CAST) index by two trained examiners. Dental pain was assessed during clinical examination. The Child Perceptions Questionnaire (CPQ) was used to assess the oral health-related quality of life, and sociodemographic data were collected. The child's school performance was measured through Provinha Brasil according to the regulations of the Ministry of Education. Descriptive statistics, bivariate analysis, and a multivariate regression model were used for data analysis. 185 boys and 189 girls participants with a mean age of 7.2 (±0.5) years were included in the study. The prevalence of dentin carious lesions for this group was 40.6 and 49.2 percent, including enamel-only lesions. The prevalence of dental pain was 2.8 percent. A high performance in reading (63.6 percent) and in mathematics (79.4 percent) was observed and were not associated with the presence of cavitated dentin carious lesions or dental pain. A significant association was found between school performance and the final CPQ score. School performance as measured by the Provinha Brasil examination was not associated with carious lesions or dental pain. Students with lower school performance had higher CPQ scores. © 2018 American Association of Public Health Dentistry.

  19. Teamwork skills, shared mental models, and performance in simulated trauma teams: an independent group design

    Directory of Open Access Journals (Sweden)

    Westli Heidi

    2010-08-01

    Full Text Available Abstract Background Non-technical skills are seen as an important contributor to reducing adverse events and improving medical management in healthcare teams. Previous research on the effectiveness of teams has suggested that shared mental models facilitate coordination and team performance. The purpose of the study was to investigate whether demonstrated teamwork skills and behaviour indicating shared mental models would be associated with observed improved medical management in trauma team simulations. Methods Revised versions of the 'Anesthetists' Non-Technical Skills Behavioural marker system' and 'Anti-Air Teamwork Observation Measure' were field tested in moment-to-moment observation of 27 trauma team simulations in Norwegian hospitals. Independent subject matter experts rated medical management in the teams. An independent group design was used to explore differences in teamwork skills between higher-performing and lower-performing teams. Results Specific teamwork skills and behavioural markers were associated with indicators of good team performance. Higher and lower-performing teams differed in information exchange, supporting behaviour and communication, with higher performing teams showing more effective information exchange and communication, and less supporting behaviours. Behavioural markers of shared mental models predicted effective medical management better than teamwork skills. Conclusions The present study replicates and extends previous research by providing new empirical evidence of the significance of specific teamwork skills and a shared mental model for the effective medical management of trauma teams. In addition, the study underlines the generic nature of teamwork skills by demonstrating their transferability from different clinical simulations like the anaesthesia environment to trauma care, as well as the potential usefulness of behavioural frequency analysis in future research on non-technical skills.

  20. Prolonged static stretching does not influence running economy despite changes in neuromuscular function.

    Science.gov (United States)

    Allison, Sarah J; Bailey, David M; Folland, Jonathan P

    2008-12-01

    The aim of this study was to examine the acute effects of prolonged static stretching (SS) on running economy. Ten male runners (VO2(peak) 60.1 +/- 7.3 ml x kg(-1) x min(-1)) performed 10 min of treadmill running at 70% VO2(peak) before and after SS and no stretching interventions. For the stretching intervention, each leg was stretched unilaterally for 40 s with each of eight different exercises and this was repeated three times. Respiratory gas exchange was measured throughout the running exercise with an automated gas analysis system. On a separate day, participants were tested for sit and reach range of motion, isometric strength and countermovement jump height before and after SS. The oxygen uptake, minute ventilation, energy expenditure, respiratory exchange ratio and heart rate responses to running were unaffected by the stretching intervention. This was despite a significant effect of SS on neuromuscular function (sit and reach range of motion, +2.7 +/- 0.6 cm; isometric strength, -5.6% +/- 3.4%; countermovement jump height -5.5% +/- 3.4%; all P influence running economy despite changes in neuromuscular function.

  1. Effectiveness of different exercises and stretching physiotherapy on pain and movement in patellofemoral pain syndrome: a randomized controlled trial.

    Science.gov (United States)

    Moyano, F Revelles; Valenza, M C; Martin, L Martin; Caballero, Y Castellote; Gonzalez-Jimenez, E; Demet, G Valenza

    2013-05-01

    To compare the effectiveness of proprioceptive neuromuscular facilitation combined with exercise, classic stretching physiotherapy intervention, and educational intervention at improving patient function and pain in patients with patellofemoral pain syndrome. Randomized, controlled, blind trial over four months. Urban population, Spain. Patients undergoing primary care for retropatellar pain. Subjects were allocated on three different treatment options: a proprioceptive neuromuscular facilitation and aerobic exercise group, a classic stretching group, and a control treatment were applied over four months under the supervision of a physiotherapist. Knee Society Score, pain reported (Visual analogue scale) and knee range of motion. Assessments were completed at baseline and after four months. 74 patients were enrolled in the study and distributed between groups. Both the proprioceptive neuromuscular facilitation and classic stretching group showed significant changes in all variables after four months intervention (p < 0.001). The difference in mean Kujala knee score changes between groups (classic stretching group vs. proprioceptive neuromuscular facilitation group vs. control group) at four months was -24.05 (95% confidence interval (CI) -30.19, -17.90), p ≤ 0.001; vs. -39.03 (95% confidence interval (CI) -42.5, -35.5), p ≤ 0.001; vs. -0.238 (95% confidence interval (CI) -1.2, 0.726), p = 0.621, respectively. A proprioceptive neuromuscular facilitation intervention protocol combined with aerobic exercise showed a better outcome than a classic stretching protocol after four months.

  2. Exploring the Black Box in Brazilian Work Groups: a Study of Diversity, Conflict and Performance

    Directory of Open Access Journals (Sweden)

    Filipe Sobral

    2012-04-01

    Full Text Available Over the last few decades, several studies have been conducted to examine the complex relationships betweenteam diversity and individual and organizational outcomes. Although, in theory, team diversity can fosterpositive organizational synergies by increasing the variance of perspectives and approaches to work differentmembers can bring, the same idiosyncratic characteristics can also engender significant difficulties resultingfrom problems in coordination, communication and conflict. This study used a sample of 44 work groups toexamine the influence of five types of diversity on team outcomes and the mediating role of task and relationalconflict on this relationship. A survey of 279 team members and interviews with the 44 team managers wereused to examine these relationships. Findings suggest that different forms of diversity impact task conflict indifferent ways, which in turn is negatively associated with job satisfaction and team performance. Results furthershow that diversity is unrelated to relational conflict; however, this type of conflict seems to hinder both jobsatisfaction and team performance. Overall, these patterns suggest a complex link between team diversity andhow work groups function.

  3. Group in-course assessment promotes cooperative learning and increases performance.

    Science.gov (United States)

    Pratten, Margaret K; Merrick, Deborah; Burr, Steven A

    2014-01-01

    The authors describe and evaluate a method to motivate medical students to maximize the effectiveness of dissection opportunities by using In-Course-Assessments (ICAs) to encourage teamwork. A student's final mark was derived by combining the group dissection mark, group mark for questions, and their individual question mark. An analysis of the impact of the ICA was performed by comparing end of module practical summative marks in student cohorts who had, or had not, participated in the ICAs. Summative marks were compared by two-way ANOVA followed by Dunnets test, or by repeated measures ANOVA, as appropriate. A cohort of medical students was selected that had experienced both practical classes without (year one) and with the new ICA structure (year two). Comparison of summative year one and year two marks illustrated an increased improvement in year two performance in this cohort. A significant increase was also noted when comparing this cohort with five preceding year two cohorts who had not experienced the ICAs (P learning resources in an active, team-based, cooperative learning environment. © 2013 American Association of Anatomists.

  4. Immediate combined effect of gastrocnemius stretching and sustained talocrural joint mobilization in individuals with limited ankle dorsiflexion: A randomized controlled trial.

    Science.gov (United States)

    Kang, Min-Hyeok; Oh, Jae-Seop; Kwon, Oh-Yun; Weon, Jong-Hyuk; An, Duk-Hyun; Yoo, Won-Gyu

    2015-12-01

    Although gastrocnemius stretching and talocrural joint mobilization have been suggested as effective interventions to address limited ankle dorsiflexion passive range of motion (DF PROM), the effects of a combination of the two interventions have not been identified. The aim of the present study was to compare the effects of gastrocnemius stretching combined with joint mobilization and gastrocnemius stretching alone. A randomized controlled trial. In total, 24 individuals with limited ankle DF PROM were randomized to undergo gastrocnemius stretching combined with joint mobilization (12 feet in 12 individuals) or gastrocnemius stretching alone (12 feet in 12 individuals) for 5 min. Ankle kinematics during gait (time to heel-off and ankle DF before heel-off), ankle DF PROM, posterior talar glide, and displacement of the myotendinous junction (MTJ) of the gastrocnemius were assessed before and after the interventions. The groups were compared using two-way repeated measures analysis of variance. Greater increases in the time to heel-off and ankle DF before heel-off during gait and posterior talar glide were observed in the stretching combined with joint mobilization group versus the stretching alone group. Ankle DF PROM and displacement of the MTJ of the gastrocnemius were increased significantly after the interventions in both groups, with no significant difference between them. These findings suggest that gastrocnemius stretching with joint mobilization needs to be considered to improve ankle kinematics during gait. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Stretch-dependent slow force response in isolated rabbit myocardium is Na+ dependent.

    Science.gov (United States)

    von Lewinski, Dirk; Stumme, Burkhard; Maier, Lars S; Luers, Claus; Bers, Donald M; Pieske, Burkert

    2003-03-15

    Stretch induces functional and trophic effects in mammalian myocardium via various signal transduction pathways. We tested stretch signal transduction on immediate and slow force response (SFR) in rabbit myocardium. Experiments were performed in isolated right ventricular muscles from adult rabbit hearts (37 degrees C, 1 Hz stimulation rate, bicarbonate-buffer). Muscles were rapidly stretched from 88% of optimal length (L88) to near optimal length (L98) for functional analysis. The resulting immediate and slow increases in twitch force (first phase and SFR, respectively) were assessed at reduced [Na+]o or without and with blockade of stretch activated ion channels (SACs), angiotensin-II (AT1) receptors, endothelin-A (ET(A)) receptors, Na+/H+-exchange (NHE1), reverse mode Na+/Ca2+-exchange (NCX), or Na+/K+-ATPase. The effects of stretch on sarcoplasmic reticulum Ca2+-load were characterized using rapid cooling contractures (RCCs). Intracellular pH was measured in BCECF-AM loaded muscles, and action potential duration (APD) was assessed using floating electrodes. On average, force increased to 216+/-8% of the pre-stretch value during the immediate phase, followed by a further increase to 273+/-10% during the SFR (n=81). RCCs significantly increased during SFR, whereas pH and APD did not change. Neither inhibition of SACs, AT1, or ET(A) receptors affected the stretch-dependent immediate phase nor SFR. In contrast, SFR was reduced by NHE inhibition and almost completely abolished by reduced [Na+]o or inhibition of reverse-mode NCX, whereas increased SFR was seen after raising [Na+]i by Na+/K+-ATPase inhibition. The data demonstrate the existence of a delayed, Na+- and Ca2+-dependent but pH and APD independent SFR to stretch in rabbit myocardium. This inotropic response appears to be independent of autocrine/paracrine AT1 or ET(A) receptor activation, but mediated through stretch-induced activation of NHE and reverse mode NCX.

  6. Effect of static and dynamic muscle stretching as part of warm up procedures on knee joint proprioception and strength.

    Science.gov (United States)

    Walsh, Gregory S

    2017-10-01

    The importance of warm up procedures prior to athletic performance is well established. A common component of such procedures is muscle stretching. There is conflicting evidence regarding the effect of static stretching (SS) as part of warm up procedures on knee joint position sense (KJPS) and the effect of dynamic stretching (DS) on KJPS is currently unknown. The aim of this study was to determine the effect of dynamic and static stretching as part warm up procedures on KJPS and knee extension and flexion strength. This study had a randomised cross-over design and ten healthy adults (20±1years) attended 3 visits during which baseline KJPS, at target angles of 20° and 45°, and knee extension and flexion strength tests were followed by 15min of cycling and either a rest period (CON), SS, or DS and repeat KJPS and strength tests. All participants performed all conditions, one condition per visit. There were warm up×stretching type interactions for KJPS at 20° (p=0.024) and 45° (p=0.018), and knee flexion (p=0.002) and extension (pwarm up procedures. However, the negative impact of SS on muscle strength limits the utility of SS before athletic performance. If stretching is to be performed as part of a warm up, DS should be favoured over SS. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. LABOR GYMNASTICS: STRETCHING EXERCISE X FLEXIONAMENT

    Directory of Open Access Journals (Sweden)

    Jacqueline Amorin Anchieta Borges da Silva, Isabel Cristina Taranto e Fernanda Piasecki

    2006-12-01

    Full Text Available Nowadays, there are many opportunities for the society to live a healthful and long life. At the same time, never people was so sedentary and without harmony. Without a healthy body and with “an occupied mind” the human loses exactly what more it needs: the disposal to produce, to coexist and to live a good life. In this context, the present research aimed to revise some terms related to labor gymnastics, which is focused in the prevention of risks related to hours of working and in the reduction of muscular tension levels that may be originated during a day of work. Thus, the present study will make a differentiation between the use of stretching and flexionament during labor gymnastic sessions.

  8. Linear viscoelastic characterization from filament stretching rheometry

    DEFF Research Database (Denmark)

    Wingstrand, Sara Lindeblad; Alvarez, Nicolas J.; Hassager, Ole

    to measure both linear and nonlinear dynamics on a single apparatus. With a software modification to the FSR motor control, we show that linear viscoelasticity can be measured via small amplitude squeeze flow (SASF). Squeeze flow is a combination of both shear and extensional flow applied by axially......Traditionally, linear viscoelasticity is measured using small amplitude oscillatory shear flow. Due to experimental difficulties, shear flows are predominately confined to the linear and mildly nonlinear regime. On the other hand, extensional flows have proven more practical in measuring...... viscoelasticity well into the nonlinear regime. Therefore at present, complete rheological characterization of a material requires two apparatuses: a shear and an extensional rheometer. This work is focused on developing a linear viscoelastic protocol for the filament stretching rheometer (FSR) in order...

  9. Buckling and stretching of thin viscous sheets

    Science.gov (United States)

    O'Kiely, Doireann; Breward, Chris; Griffiths, Ian; Howell, Peter; Lange, Ulrich

    2016-11-01

    Thin glass sheets are used in smartphone, battery and semiconductor technology, and may be manufactured by producing a relatively thick glass slab and subsequently redrawing it to a required thickness. The resulting sheets commonly possess undesired centerline ripples and thick edges. We present a mathematical model in which a viscous sheet undergoes redraw in the direction of gravity, and show that, in a sufficiently strong gravitational field, buckling is driven by compression in a region near the bottom of the sheet, and limited by viscous resistance to stretching of the sheet. We use asymptotic analysis in the thin-sheet, low-Reynolds-number limit to determine the centerline profile and growth rate of such a viscous sheet.

  10. Loads applied to fixations for chain stretching

    Energy Technology Data Exchange (ETDEWEB)

    Ahrens, K; Brychta, P

    1985-06-01

    The chains of scraper chain conveyors must be pre-stretched during standstill in order to compensate the elongations occurring during operation. They require frequent retensiening in order to meet the varying operational requirements. During tensioning, the chains are fixed in a point in the top run by means of fixation elements. The authors present a method for calculating the retaining force needed in the fixations. There are three different initial conditions of the chain before trensioning: Tensionsfree chain, pretensioned chain (stressed chain), slack chain. In all three cases, it is important to find out whether or nor the tensioning drive reaches full speed. The method of calculation is illustrated by the example of a scraper chain conveyor; it enables the establishment of rules for tensioning without damaging the chain and is a good basis for the dimensioning of new types of fixation elements.

  11. Aerothermodynamic properties of stretched flames in enclosures

    Science.gov (United States)

    Rotman, D. A.; Oppenheim, A. K.

    Flames are stretched by being pulled along their frontal surface by the flow field in which they reside. Their trajectories tend to approach particle paths, acquiring eventually the role of contact boundaries, -interfaces between the burnt and unburnt medium that may broaden solely as a consequence of diffusion. Fundamental properties of flow fields governing such flames are determined here on the basis of the zero Mach number model, providng a rational method of approach to the computational analysis of combustion fields in enclosures where, besides the aerodynamic properties flow, the thermodynamic process of compression must be taken into account. To illustrate its application, the method is used to reveal the mechanism of formation of a tulip-shape flame in a rectangular enclosure under nonturbulent flow conditions.

  12. High Performance Platinum Group Metal Free Membrane Electrode Assemblies through Control of Interfacial Processes

    Energy Technology Data Exchange (ETDEWEB)

    Ayers, Katherine [Proton Energy Systems, Wallingford, CT (United States); Capuano, Christopher [Proton Energy Systems, Wallingford, CT (United States); Atanassov, Plamen [Univ. of New Mexico, Albuquerque, NM (United States); Mukerjee, Sanjeev [Northeastern Univ., Boston, MA (United States); Hickner, Michael [Pennsylvania State Univ., University Park, PA (United States)

    2017-11-29

    The quantitative goal of this project was to produce a high-performance anion exchange membrane water electrolyzer (AEM-WE) completely free of platinum group metals (PGMs), which could operate for at least 500 hours with less than 50 microV/hour degradation, at 500 mA/cm2. To achieve this goal, work focused on the optimization of electrocatalyst conductivity, with dispersion and utilization in the membrane electrode assembly (MEA) improved through refinement of deposition techniques. Critical factors were also explored with significant work undertaken by Northeastern University to further understand catalyst-membrane-ionomer interfaces and how they differ from liquid electrolyte. Water management and optimal cell operational parameters were established through the design, fabrication, and test of a new test station at Proton specific for AEM evaluation. Additionally, AEM material stability and robustness at high potentials and gas evolution conditions were advanced at Penn State.

  13. Effect of Active-Assisted Stretching of 30 Seconds and 60 Seconds in Muscle Force

    Directory of Open Access Journals (Sweden)

    Mirian dos Santos Monteiro

    2018-01-01

    Full Text Available This study aims to analyze the interference of the active-assisted stretching technique in muscle strength. Participating in this study were 39 healthy and physically active individuals subdivided into three groups of active-assisted stretching G30 - 30 seconds, G60 - 60 seconds and CG - control. The muscular strength was evaluated using the isokinetic dynamometer, obtaining the analyzed conditions of torque peak, total work and agonist and antagonist relationship of the dorsiflexor and flexor muscles ankle. The values obtained were statistically analyzed by the SPSS from the “t-test for paired sample” (p ≤ 0.05. When analyzing the effect produced by the stretching, it was observed that the 30-second elongation showed a reduction of the average of the muscular torque in all conditions analyzed, with the exception of the relation between the agonist and the left antagonist and the total work of the right plantar flexors, the G60 - 60 seconds group had a reduction in average muscle torque in all conditions analyzed, except for the relation between agonist and left antagonist that obtained an increase in muscle torque and the CG - control group, there was a reduction in the average of the muscular torque in all the analyzed conditions, except for the torque and total work of the left plantar flexor muscles that presented increase. Thus, it can be concluded that there were differences between the groups of active-assisted stretching of 30 and 60 and that the effect produced by stretching did not present a significant reduction of muscle strength.

  14. The Method of Optimization of Hydropower Plant Performance for Use in Group Active Power Controller

    Directory of Open Access Journals (Sweden)

    Glazyrin G.V.

    2017-04-01

    Full Text Available The problem of optimization of hydropower plant performance is considered in this paper. A new method of calculation of optimal load-sharing is proposed. The method is based on application of incremental water flow curves representing relationship between the per unit increase of water flow and active power. The optimal load-sharing is obtained by solving the nonlinear equation governing the balance of total active power and the station power set point with the same specific increase of water flow for all turbines. Unlike traditional optimization techniques, the solution of the equation is obtained without taking into account unit safe operating zones. Instead, if calculated active power of a unit violates the permissible power range, load-sharing is recalculated for the remaining generating units. Thus, optimal load-sharing algorithm suitable for digital control systems is developed. The proposed algorithm is implemented in group active power controller in Novosibirsk hydropower plant. An analysis of operation of group active power controller proves that the application of the proposed method allows obtaining optimal load-sharing at each control step with sufficient precision.

  15. An application of seasonal ARIMA models on group commodities to forecast Philippine merchandise exports performance

    Science.gov (United States)

    Natividad, Gina May R.; Cawiding, Olive R.; Addawe, Rizavel C.

    2017-11-01

    The increase in the merchandise exports of the country offers information about the Philippines' trading role within the global economy. Merchandise exports statistics are used to monitor the country's overall production that is consumed overseas. This paper investigates the comparison between two models obtained by a) clustering the commodity groups into two based on its proportional contribution to the total exports, and b) treating only the total exports. Different seasonal autoregressive integrated moving average (SARIMA) models were then developed for the clustered commodities and for the total exports based on the monthly merchandise exports of the Philippines from 2011 to 2016. The data set used in this study was retrieved from the Philippine Statistics Authority (PSA) which is the central statistical authority in the country responsible for primary data collection. A test for significance of the difference between means at 0.05 level of significance was then performed on the forecasts produced. The result indicates that there is a significant difference between the mean of the forecasts of the two models. Moreover, upon a comparison of the root mean square error (RMSE) and mean absolute error (MAE) of the models, it was found that the models used for the clustered groups outperform the model for the total exports.

  16. Evaluation of the performance of diagnosis-related groups and similar casemix systems: methodological issues.

    Science.gov (United States)

    Palmer, G; Reid, B

    2001-05-01

    With the increasing recognition and application of casemix for managing and financing healthcare resources, the evaluation of alternative versions of systems such as diagnosis-related groups (DRGs) has been afforded high priority by governments and researchers in many countries. Outside the United States, an important issue has been the perceived need to produce local versions, and to establish whether or not these perform more effectively than the US-based classifications. A discussion of casemix evaluation criteria highlights the large number of measures that may be used, the rationale and assumptions underlying each measure, and the problems in interpreting the results. A review of recent evaluation studies from a number of countries indicates that considerable emphasis has been placed on the predictive validity criterion, as measured by the R2 statistic. However, the interpretation of the findings has been affected greatly by the methods used, especially the treatment and definition of outlier cases. Furthermore, the extent to which other evaluation criteria have been addressed has varied widely. In the absence of minimum evaluation standards, it is not possible to draw clear-cut conclusions about the superiority of one version of a casemix system over another, the need for a local adaptation, or the further development of an existing version. Without the evidence provided by properly designed studies, policy-makers and managers may place undue reliance on subjective judgments and the views of the most influential, but not necessarily best informed, healthcare interest groups.

  17. Performance of radioimmunoassays for digoxin as evaluated by a group experiment

    International Nuclear Information System (INIS)

    Dwenger, A.; Friedel, R.; Trautschold, I.

    1977-01-01

    In order to gather informations on the performance of routinely employed test system for the radioimmunological determination of digoxin in serum a group experiment was set up in which 36 laboratories in the Federal Republic of Germany took part. They were asked to determine the digoxin content in 25 specimens including a recovery curve, sera with pathologic composition and known concentrations of digoxin, sera from a pharmacokinetic study and commercial control sera. This identity of the specimens was withheld from the participants. As far as accuracy and precision are concerned the results reported for a total of 54 assays were better than those obtained in group experiments on radioimmunological determination of hormones. Recovery ranged from 90% to 110% in 57%, from 80% to 120% in 85% of the assays. Reproducibility in the series expressed as coefficient of variation was better than 5% in 54%, better than 10% in 85% of the assays. Considerable differences were found for the cross-reactivities of antibodies with digitoxin and metabolites of spironolactone. Dysproteinemia seems to be an unsolved problem whereas moderate hemolysis and hyperlipemia did not lead to severe errors. Improvements, especially with respect to inter-laboratory variances can be expected mainly from a further standardization of standard preparations. (orig.) [de

  18. Performance and parasite control of different genetic groups of lambs finished in irrigated pasture

    Directory of Open Access Journals (Sweden)

    G.A. Fernandes Júnior

    2015-06-01

    Full Text Available The aim of this study was to compare the following four genetic groups of hair sheep: Santa Inês (SI, Morada Nova (MN, Brazilian Somali (BS, and the F1 1/2Dorper x 1/2Morada Nova crossbreed on traits related to growth and parasitic infection. Thirty-three male lambs of the same age and of simple birth, under the same pre-weaning management conditions were used in the experiment. After weaning the animals were housed in a completely randomized design in paddocks made of Panicum maximum cv. Tanzania. Along the course of the research, the performance of the four groups of sheep was observed to be negatively affected by gastrointestinal parasites, but there was a genotype effect to the average daily weight gain (ADWG, where the SI and F1 genotypes presented higher values. The effects of genotype, time and genotype x time interaction were significant in weight and corporal score (CS measurements. The BS lambs had the highest CS values throughout the experiment despite not presenting greater weight gain when compared to the SI and F1 breeds. There were also significant effects of time and genotype x time interaction for packed cell volume (PCV and FAMACHA© score (FAM and only the time effect was significant in the total number of eggs per gram (EPG and total plasma protein (TPP. The MN lambs showed higher PCV values and unlike the other groups, presented a FAMACHA© score below 3 and PCV above 23% even having a higher EPG tendency, especially in the initial phase, indicating a possible higher resilience to infection caused by gastrointestinal parasites.

  19. EFFECTIVENESS OF INSTUMENTAL ASSISTED SOFT TISSUE MOBILIZATION TECHNIQUE WITH STATIC STRETCHING IN SUBJECTS WITH PLANTAR FASCIITIS

    Directory of Open Access Journals (Sweden)

    Vinod Babu. K

    2014-08-01

    Full Text Available Background: Instrumental assisted soft tissue mobilization and static stretching found to be effective in plantar fasciitis, however the combined effectiveness of these techniques were unknown. The purpose of this study is to find the effect of Instrumental assisted soft tissue mobilization technique for plantar fascia combined with static stretching of triceps surae for subjects with chronic stage of Plantar Fasciitis on pain intensity, ankle dorsiflexion range of motion and functional disability. Methods: An experimental study design, selected subjects with chronic Plantar Fasciitis randomized subjects into each Study and Control group. Total of 40 subject’s data who completed study, 20 in each group, was used for analysis. Control group received conventional exercise while Study group received conventional exercises with Instrumental assisted soft tissue mobilization combined with static stretching of triceps surae muscle. Outcome measurements such as Intensity of pain using Numerical Pain Rating Scale-101 (NPRS-101, function disability using Foot Function Index Pain Subscale (FFI and ankle dorsiflexion active range of motion using Goniometer was measured before and after 2 weeks of intervention. Results: There is statistically significant improvement in means of NRS-101, ankle dorsiflexion active range of motion and Foot Function Index Pain Subscale after intervention in both groups. When the post-intervention means were compared between Study and Control group after 2 weeks of treatment there is statistically significant difference in means between the groups whereas study group showed greater percentage of improvement than control group. Conclusion: It is concluded that Instrumental assisted soft tissue mobilization technique combined with static stretching of triceps surae muscle is significantly effective than conventional exercises on reducing pain, improving ankle dorsiflexion range of motion and functional disability for subjects

  20. Direct alcohol fuel cells: Increasing platinum performance by modification with sp-group metals

    Science.gov (United States)

    Figueiredo, Marta C.; Sorsa, Olli; Doan, Nguyet; Pohjalainen, Elina; Hildebrand, Helga; Schmuki, Patrik; Wilson, Benjamin P.; Kallio, Tanja

    2015-02-01

    By using sp group metals as modifiers, the catalytic properties of Pt can be improved toward alcohols oxidation. In this work we report the performance increase of direct alcohol fuel cells (DAFC) fuelled with ethanol or 2-propanol with platinum based anode electrodes modified with Bi and Sb adatoms. For example, by simply adding Sb to the Pt/C based anode ink during membrane electrode assembly fabrication of a direct ethanol fuel cell (DEFC) its performance is improved three-fold, with more than 100 mV increase in the open circuit potential. For the fuel cell fuelled with 2-propanol high power densities are obtained at very high potentials with these catalyst materials suggesting a great improvement for practical applications. Particularly in the case of Pt/C-Bi, the improvement is such that within 0.6 V (from 0.7 to 0.1 V) the power densities are between 7 and 9 mW/cm2. The results obtained with these catalysts are in the same range as those obtained with other bimetallic catalysts comprising of PtRu and PtSn, which are currently considered to be the best for these type of fuel cells and that are obtained by more complicated (and consequently more expensive) methods.

  1. Performance of some supervised and unsupervised multivariate techniques for grouping authentic and unauthentic Viagra and Cialis

    Directory of Open Access Journals (Sweden)

    Michel J. Anzanello

    2014-09-01

    Full Text Available A typical application of multivariate techniques in forensic analysis consists of discriminating between authentic and unauthentic samples of seized drugs, in addition to finding similar properties in the unauthentic samples. In this paper, the performance of several methods belonging to two different classes of multivariate techniques–supervised and unsupervised techniques–were compared. The supervised techniques (ST are the k-Nearest Neighbor (KNN, Support Vector Machine (SVM, Probabilistic Neural Networks (PNN and Linear Discriminant Analysis (LDA; the unsupervised techniques are the k-Means CA and the Fuzzy C-Means (FCM. The methods are applied to Infrared Spectroscopy by Fourier Transform (FTIR from authentic and unauthentic Cialis and Viagra. The FTIR data are also transformed by Principal Components Analysis (PCA and kernel functions aimed at improving the grouping performance. ST proved to be a more reasonable choice when the analysis is conducted on the original data, while the UT led to better results when applied to transformed data.

  2. Performance of Hitchens-Pike-Todd-Hewitt medium for group B streptococcus screening in pregnant women.

    Directory of Open Access Journals (Sweden)

    Simone Cristina Castanho Sabaini de Melo

    Full Text Available Group B streptococcus (GBS, which commonly colonizes the female genital tract and rectum, can cause infections in newborns with varying severity, possibly leading to death. The aim of the present study was to evaluate Hitchens-Pike-Todd-Hewitt (HPTH medium performance for GBS screening in pregnant women. A descriptive analytical cross-sectional study was performed with 556 pregnant women, of which 496 were at 35-37 weeks of gestation and 60 were at ≥ 38 weeks of gestation. The study was conducted from September 2011 to March 2014 in northern Paraná, Brazil. Vaginal and anorectal clinical specimens from each pregnant woman were plated on sheep blood agar (SBA and seeded on HPTH medium and Todd-Hewitt enrichment broth. Of the 496 pregnant women at 35-37 weeks of gestation, 141 (28.4% were positive for GBS, based on the combination of the three culture media and clinical specimens. The GBS colonization rates that were detected by each medium were 22.2% for HPTH medium, 21.2% for SBA, and 13.1% for Todd-Hewitt enrichment broth. Of the 60 pregnant women at ≥ 38 weeks of gestation, seven (11.7% were positive for GBS. These results demonstrate that HPTH medium and SBA were more sensitive than Todd-Hewitt enrichment broth for GBS screening in pregnant women and good GBS recovery in culture, indicating that the two media should be used together for vaginal and anorectal specimens.

  3. Dynamics of safety performance and culture: a group model building approach.

    Science.gov (United States)

    Goh, Yang Miang; Love, Peter E D; Stagbouer, Greg; Annesley, Chris

    2012-09-01

    The management of occupational health and safety (OHS) including safety culture interventions is comprised of complex problems that are often hard to scope and define. Due to the dynamic nature and complexity of OHS management, the concept of system dynamics (SD) is used to analyze accident prevention. In this paper, a system dynamics group model building (GMB) approach is used to create a causal loop diagram of the underlying factors influencing the OHS performance of a major drilling and mining contractor in Australia. While the organization has invested considerable resources into OHS their disabling injury frequency rate (DIFR) has not been decreasing. With this in mind, rich individualistic knowledge about the dynamics influencing the DIFR was acquired from experienced employees with operations, health and safety and training background using a GMB workshop. Findings derived from the workshop were used to develop a series of causal loop diagrams that includes a wide range of dynamics that can assist in better understanding the causal influences OHS performance. The causal loop diagram provides a tool for organizations to hypothesize the dynamics influencing effectiveness of OHS management, particularly the impact on DIFR. In addition the paper demonstrates that the SD GMB approach has significant potential in understanding and improving OHS management. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. A workplace stretching program. Physiologic and perception measurements before and after participation.

    Science.gov (United States)

    Moore, T M

    1998-12-01

    The purpose of this study was to implement a primary prevention program in the workplace targeted to prevent muscle strains. Physiologic and perception measurements were taken before and after participation in a stretching program developed to improve flexibility through conditioning. A one group pre-test post-test design was used with 60 employees enrolled in a 36 session stretching program in the workplace. Flexibility was measured by a flexibility profile including the sit and reach test, bilateral body rotation measurements, and shoulder rotation measurements. A statistically significant increase was found in all flexibility measurements at the conclusion of the study for the participants as a total group. Perception, as measured by the Fox Physical Self Perception Profile, was statistically significant in relation to participants' perceptions of their body attractiveness, physical conditioning, and overall self worth at the program's conclusion. In addition, participants who completed the program had zero occurrences of musculoskeletal injuries during the 2 month period. The results of this study suggest that continued development and implementation of stretching programs in the workplace may benefit employees by increasing flexibility and potentially preventing injuries due to muscle strains. Stretching programs in the workplace also may improve components of employees' perceptions of their physical bodies.

  5. Agricultural producers’ groups in the Czech Republic: introductory review and discussion of the problem area economic performance measurement

    Directory of Open Access Journals (Sweden)

    Jan Vavřina

    2012-01-01

    Full Text Available Each company is surrounded by the micro- and macro-environment affecting also its economic performance. These factors are not only individual accounting entries, but also analytical inputs as the internal company processes, management of costs or short-term financial decisions and specifically in the case of agriculture within the EU also the public subsidy schemes implemented through the EU Common Agricultural Policy. Groups of agricultural producers are created as a response to current market dynamics and the opportunity for each agricultural enterprise regardless the size. In this paper, the basis for agricultural cooperation is provided, traditional economic performance measures are presented and their applicability on the sample of agricultural producers’ groups and wholesale entities is empirically verified. Wholesale entities are analysed by its business activity and performance features to consider whether they are suitable peer group for comparing economic performance of examined agricultural producers’ group. Since the economic performance of agricultural producers’ groups directly affects the economic performance of all participating entities, and vice versa, their economic performance measurement may involve specific constraints. According to the structure and characteristics of agricultural producers’ groups may be inferred that whilst the common performance measurement techniques are applicable on the majority of companies, agricultural producers’ groups represent specific entities and therefore need adjusted performance measurement approach.

  6. Performance Analysis of Hierarchical Group Key Management Integrated with Adaptive Intrusion Detection in Mobile ad hoc Networks

    Science.gov (United States)

    2016-04-05

    applications in wireless networks such as military battlefields, emergency response, mobile commerce , online gaming, and collaborative work are based on the...www.elsevier.com/locate/peva Performance analysis of hierarchical group key management integrated with adaptive intrusion detection in mobile ad hoc...Accepted 19 September 2010 Available online 26 September 2010 Keywords: Mobile ad hoc networks Intrusion detection Group communication systems Group

  7. The stretch reflex and the contributions of C David Marsden

    Directory of Open Access Journals (Sweden)

    Kalyan B Bhattacharyya

    2017-01-01

    Full Text Available The stretch reflex or myotatic reflex refers to the contraction of a muscle in response to its passive stretching by increasing its contractility as long as the stretch is within physiological limits. For ages, it was thought that the stretch reflex was of short latency and it was synonymous with the tendon reflex, subserving the same spinal reflex arc. However, disparities in the status of the two reflexes in certain clinical situations led Marsden and his collaborators to carry out a series of experiments that helped to establish that the two reflexes had different pathways. That the two reflexes are dissociated has been proved by the fact that the stretch reflex and the tendon reflex, elicited by stimulation of the same muscle, have different latencies, that of the stretch reflex being considerably longer. They hypothesized that the stretch reflex had a transcortical course before it reached the spinal motor neurons for final firing. Additionally, the phenomenon of stimulus-sensitive cortical myoclonus lent further evidence to the presence of the transcortical loop where the EEG correlate preceded the EMG discharge. This concept has been worked out by later neurologists in great detail , and the general consensus is that indeed, the stretch reflex is endowed with a conspicuous transcortical component.

  8. Possible stretched exponential parametrization for humidity absorption in polymers.

    Science.gov (United States)

    Hacinliyan, A; Skarlatos, Y; Sahin, G; Atak, K; Aybar, O O

    2009-04-01

    Polymer thin films have irregular transient current characteristics under constant voltage. In hydrophilic and hydrophobic polymers, the irregularity is also known to depend on the humidity absorbed by the polymer sample. Different stretched exponential models are studied and it is shown that the absorption of humidity as a function of time can be adequately modelled by a class of these stretched exponential absorption models.

  9. Immediate Effects of Neurodynamic Sliding versus Muscle Stretching on Hamstring Flexibility in Subjects with Short Hamstring Syndrome

    Science.gov (United States)

    Castellote-Caballero, Yolanda; Valenza, Maríe C.; Puentedura, Emilio J.; Fernández-de-las-Peñas, César; Alburquerque-Sendín, Francisco

    2014-01-01

    Background. Hamstring injuries continue to affect active individuals and although inadequate muscle extensibility remains a commonly accepted factor, little is known about the most effective method to improve flexibility. Purpose. To determine if an isolated neurodynamic sciatic sliding technique would improve hamstring flexibility to a greater degree than stretching or a placebo intervention in asymptomatic subjects with short hamstring syndrome (SHS). Study Design. Randomized double-blinded controlled trial. Methods. One hundred and twenty subjects with SHS were randomized to 1 of 3 groups: neurodynamic sliding, hamstring stretching, and placebo control. Each subject's dominant leg was measured for straight leg raise (SLR) range of motion (ROM) before and after interventions. Data were analyzed with a 3 × 2 mixed model ANOVA followed by simple main effects analyses. Results. At the end of the study, more ROM was observed in the Neurodynamic and Stretching groups compared to the Control group and more ROM in the Neurodynamic group compared to Stretching group. Conclusion. Findings suggest that a neurodynamic sliding technique will increase hamstring flexibility to a greater degree than static hamstring stretching in healthy subjects with SHS. Clinical Relevance. The use of neurodynamic sliding techniques to improve hamstring flexibility in sports may lead to a decreased incidence in injuries; however, this needs to be formally tested. PMID:26464889

  10. Immediate Effects of Neurodynamic Sliding versus Muscle Stretching on Hamstring Flexibility in Subjects with Short Hamstring Syndrome

    Directory of Open Access Journals (Sweden)

    Yolanda Castellote-Caballero

    2014-01-01

    Full Text Available Background. Hamstring injuries continue to affect active individuals and although inadequate muscle extensibility remains a commonly accepted factor, little is known about the most effective method to improve flexibility. Purpose. To determine if an isolated neurodynamic sciatic sliding technique would improve hamstring flexibility to a greater degree than stretching or a placebo intervention in asymptomatic subjects with short hamstring syndrome (SHS. Study Design. Randomized double-blinded controlled trial. Methods. One hundred and twenty subjects with SHS were randomized to 1 of 3 groups: neurodynamic sliding, hamstring stretching, and placebo control. Each subject’s dominant leg was measured for straight leg raise (SLR range of motion (ROM before and after interventions. Data were analyzed with a 3×2 mixed model ANOVA followed by simple main effects analyses. Results. At the end of the study, more ROM was observed in the Neurodynamic and Stretching groups compared to the Control group and more ROM in the Neurodynamic group compared to Stretching group. Conclusion. Findings suggest that a neurodynamic sliding technique will increase hamstring flexibility to a greater degree than static hamstring stretching in healthy subjects with SHS. Clinical Relevance. The use of neurodynamic sliding techniques to improve hamstring flexibility in sports may lead to a decreased incidence in injuries; however, this needs to be formally tested.

  11. Is Group Polling Better? An Investigation of the Effect of Individual and Group Polling Strategies on Students' Academic Performance, Anxiety, and Attention

    Science.gov (United States)

    Sun, Jerry Chih-Yuan; Chen, Ariel Yu-Zhen; Yeh, Katherine Pin-Chen; Cheng, Yu-Ting; Lin, Yu-Yan

    2018-01-01

    The purpose of this study was to investigate the effect of polling technologies (clickers or tablets) integrated with strategies (individual or group) on students' academic performance, anxiety, and attention. The participants were 34 students enrolled in an educational research methodology course. The anxiety scale, pre- and in-class quizzes,…

  12. Positive is usually good, negative is not always bad: The effects of group affect on social integration and task performance.

    Science.gov (United States)

    Knight, Andrew P; Eisenkraft, Noah

    2015-07-01

    Grounded in a social functional perspective, this article examines the conditions under which group affect influences group functioning. Using meta-analysis, the authors leverage heterogeneity across 39 independent studies of 2,799 groups to understand how contextual factors-group affect source (exogenous or endogenous to the group) and group life span (one-shot or ongoing)-moderate the influence of shared feelings on social integration and task performance. As predicted, results indicate that group positive affect has consistent positive effects on social integration and task performance regardless of contextual idiosyncrasies. The effects of group negative affect, on the other hand, are context-dependent. Shared negative feelings promote social integration and task performance when stemming from an exogenous source or experienced in a 1-shot group, but undermine social integration and task performance when stemming from an endogenous source or experienced in an ongoing group. The authors discuss implications of their findings and highlight directions for future theory and research on group affect. (c) 2015 APA, all rights reserved).

  13. Societal output and use of research performed by health research groups

    Directory of Open Access Journals (Sweden)

    van Ark Gerrit

    2010-10-01

    Full Text Available Abstract The last decade has seen the evaluation of health research pay more and more attention to societal use and benefits of research in addition to scientific quality, both in qualitative and quantitative ways. This paper elaborates primarily on a quantitative approach to assess societal output and use of research performed by health research groups (societal quality of research. For this reason, one of the Dutch university medical centres (i.e. the Leiden University Medical Center (LUMC was chosen as the subject of a pilot study, because of its mission to integrate top patient care with medical, biomedical and healthcare research and education. All research departments were used as units of evaluation within this university medical centre. The method consisted of a four-step process to reach a societal quality score per department, based on its (research outreach to relevant societal stakeholders (the general public, healthcare professionals and the private sector. For each of these three types of stakeholders, indicators within four modes of communication were defined (knowledge production, knowledge exchange, knowledge use and earning capacity. These indicators were measured by a bottom-up approach in a qualitative way (i.e. all departments of the LUMC were asked to list all activities they would consider to be of societal relevance, after which they were converted into quantitative scores. These quantitative scores could then be compared to standardised scientific quality scores that are based on scientific publications and citations of peer-reviewed articles. Based on the LUMC pilot study, only a weak correlation was found between societal and scientific quality. This suggests that societal quality needs additional activities to be performed by health research groups and is not simply the consequence of high scientific quality. Therefore we conclude that scientific and societal evaluation should be considered to be synergistic in terms

  14. Effect of one stretch a week applied to the immobilized soleus muscle on rat muscle fiber morphology

    Directory of Open Access Journals (Sweden)

    Gomes A.R.S.

    2004-01-01

    Full Text Available We determined the effect of stretching applied once a week to the soleus muscle immobilized in the shortened position on muscle fiber morphology. Twenty-six male Wistar rats weighing 269 ± 26 g were divided into three groups. Group I, the left soleus was immobilized in the shortened position for 3 weeks; group II, the soleus was immobilized in the shortened position and stretched once a week for 3 weeks; group III, the soleus was submitted only to stretching once a week for 3 weeks. The medial part of the soleus muscle was frozen for histology and muscle fiber area evaluation and the lateral part was used for the determination of number and length of serial sarcomeres. Soleus muscle submitted only to immobilization showed a reduction in weight (44 ± 6%, P = 0.002, in serial sarcomere number (23 ± 15% and in cross-sectional area of the fibers (37 ± 31%, P < 0.001 compared to the contralateral muscles. The muscle that was immobilized and stretched showed less muscle fiber atrophy than the muscles only immobilized (P < 0.05. Surprisingly, in the muscles submitted only to stretching, fiber area was decreased compared to the contralateral muscle (2548 ± 659 vs 2961 ± 806 µm², respectively, P < 0.05. In conclusion, stretching applied once a week for 40 min to the soleus muscle immobilized in the shortened position was not sufficient to prevent the reduction of muscle weight and of serial sarcomere number, but provided significant protection against muscle fiber atrophy. In contrast, stretching normal muscles once a week caused a reduction in muscle fiber area.

  15. The effects of different gender groupings on middle school students' performance in science lab

    Science.gov (United States)

    Drab, Deborah D.

    Grouping students for labs in science classes is a common practice. This mixed methods quasi-experimental action research study examines homogeneous and heterogeneous gender grouping strategies to determine what gender grouping strategy is the most effective in a coeducational science classroom setting. Sixth grade students were grouped in same-gender and mixed-gender groups, alternating each quarter. Over the course of an academic year, data were collected from four sources. The teacher-researcher observed groups working during hands-on activities to collect data on student behaviors. Students completed post-lab questionnaires and an end-of-course questionnaire about their preferences and experiences in the different grouping strategies. Student scores on written lab assignments were also utilized. Data analysis focused on four areas: active engagement, student achievement, student perceptions of success and cooperative teamwork. Findings suggest that teachers may consider grouping students of different ability levels according to different gender grouping strategies to optimize learning.

  16. Effects of contract-relax vs static stretching on stretch-induced strength loss and length-tension relationship

    DEFF Research Database (Denmark)

    Balle, S S; Magnusson, S P; McHugh, M P

    2015-01-01

    The purpose of this study was to determine the acute effects of contract-relax stretching (CRS) vs static stretching (SS) on strength loss and the length-tension relationship. We hypothesized that there would be a greater muscle length-specific effect of CRS vs SS. Isometric hamstring strength wa...

  17. Amide group anchored glucose oxidase based anodic catalysts for high performance enzymatic biofuel cell

    Science.gov (United States)

    Chung, Yongjin; Ahn, Yeonjoo; Kim, Do-Heyoung; Kwon, Yongchai

    2017-01-01

    A new enzyme catalyst is formed by fabricating gold nano particle (GNP)-glucose oxidase (GOx) clusters that are then attached to polyethyleneimine (PEI) and carbon nanotube (CNT) with cross-linkable terephthalaldehyde (TPA) (TPA/[CNT/PEI/GOx-GNP]). Especially, amide bonds belonging to TPA play an anchor role for incorporating rigid bonding among GNP, GOx and CNT/PEI, while middle size GNP is well bonded with thiol group of GOx to form strong GNP-GOx cluster. Those bonds are identified by chemical and electrochemical characterizations like XPS and cyclic voltammogram. The anchording effect of amide bonds induces fast electron transfer and strong chemical bonding, resulting in enhancements in (i) catalytic activity, (ii) amount of immobilized GOx and (ii) performance of enzymatic biofuel cell (EBC) including the catalyst. Regarding the catalytic activity, the TPA/[CNT/PEI/GOx-GNP] produces high electron transfer rate constant (6 s-1), high glucose sensitivity (68 μA mM-1 cm-2), high maximum current density (113 μA cm-2), low charge transfer resistance (17.0 Ω cm2) and long-lasting durability while its chemical structure is characterized by XPS confirming large portion of amide bond. In EBC measurement, it has high maximum power density (0.94 mW cm-2) compatible with catalytic acitivity measurements.

  18. Developing porous carbon with dihydrogen phosphate groups as sulfur host for high performance lithium sulfur batteries

    Science.gov (United States)

    Cui, Yanhui; Zhang, Qi; Wu, Junwei; Liang, Xiao; Baker, Andrew P.; Qu, Deyang; Zhang, Hui; Zhang, Huayu; Zhang, Xinhe

    2018-02-01

    Carbon matrix (CM) derived from biomass is low cost and easily mass produced, showing great potential as sulfur host for lithium sulfur batteries. In this paper we report on a dihydrogen phosphate modified CM (PCM-650) prepared from luffa sponge (luffa acutangula) by phosphoric acid treatment. The phosphoric acid not only increases the surface area of the PCM-650, but also introduces dihydrogen phosphate onto PCM-650 (2.28 at% P). Sulfur impregnated (63.6 wt%) PCM-650/S, in comparison with samples with less dihydrogen phosphate LPCM-650/S, shows a significant performance improvement. XPS analysis is conducted for sulfur at different stages, including sulfur (undischarged), polysulfides (discharge to 2.1 V) and short chain sulfides (discharge to 1.7 V). The results consistently show chemical shifts for S2p in PCM-650, suggesting an enhanced adsorption effect. Furthermore, density functional theory (DFT) calculations is used to clarify the molecular binding: carbon/sulfur (0.86 eV), carbon/Li2S (0.3 eV), CH3-O-PO3H2/sulfur (1.24 eV), and CH3-O-PO3H2/Li2S (1.81 eV). It shows that dihydrogen phosphate group can significantly enhance the binding with sulfur and sulfide, consistent with XPS results. Consequently a CM functionalised with dihydrogen phosphate shows great potential as the sulfur host in a Li-S battery.

  19. Characterization of mechanical behavior of a porcine pulmonary artery strip using a randomized uniaxial stretch and stretch-rate protocol

    Directory of Open Access Journals (Sweden)

    Criscione John C

    2008-01-01

    Full Text Available Abstract Background Much of the experimental work in soft tissue mechanics has been focused on fitting approximate relations for specific tissue types from aggregate data on multiple samples of the tissue. Such relations are needed for modeling applications and have reasonable predictability – especially given the natural variance in specimens. There is, however, much theoretical and experimental work to be done in determining constitutive behaviors for particular specimens and tissues. In so doing, it may be possible to exploit the natural variation in tissue ultrastructure – so to relate ultrastructure composition to tissue behavior. Thus, this study focuses on an experimental method for determining constitutive behaviors and illustrates the method with analysis of a porcine pulmonary artery strip. The method characterizes the elastic part of the response (implicitly in terms of stretch and the inelastic part in terms of short term stretch history (i.e., stretch-rate Ht2, longer term stretch history Ht1, and time since the start of testing T. Methods A uniaxial testing protocol with a random stretch and random stretch-rate was developed. The average stress at a particular stretch was chosen as the hyperelastic stress response, and deviation from the mean at this particular stretch is chosen as the inelastic deviation. Multivariable Linear Regression Analysis (MLRA was utilized to verify if Ht2, Ht1, and T are important factors for characterizing the inelastic deviation. For acquiring Ht2 and Ht1, an integral function type of stretch history was employed with time constants chosen from the relaxation spectrum of an identical size strip from the same tissue with the same orientation. Finally, statistical models that characterize the inelasticity were developed at various, nominal values of stretch, and their predictive capability was examined. Results Inelastic deviation from hyperelasticity was high (31% for low stretch and declined

  20. When none of us perform better than all of us together: the role of analogical decision rules in groups.

    Directory of Open Access Journals (Sweden)

    Nicoleta Meslec

    Full Text Available During social interactions, groups develop collective competencies that (ideally should assist groups to outperform average standalone individual members (weak cognitive synergy or the best performing member in the group (strong cognitive synergy. In two experimental studies we manipulate the type of decision rule used in group decision-making (identify the best vs. collaborative, and the way in which the decision rules are induced (direct vs. analogical and we test the effect of these two manipulations on the emergence of strong and weak cognitive synergy. Our most important results indicate that an analogically induced decision rule (imitate-the-successful heuristic in which groups have to identify the best member and build on his/her performance (take-the-best heuristic is the most conducive for strong cognitive synergy. Our studies bring evidence for the role of analogy-making in groups as well as the role of fast-and-frugal heuristics for group decision-making.

  1. The Relationship of Gender and Academic Performance to Motivation: Within-Ethnic-Group Variations.

    Science.gov (United States)

    Rouse, Kimberly A. Gordon; Austin, James T.

    2002-01-01

    Three studies examined within-ethnic-group variations in the relationship of grade point average and gender to motivation among African American, Hispanic American, and Euro-American students. Survey data revealed patterns of significant within-ethnic-group differences that varied across ethnic groups. In general, males demonstrated more…

  2. Quantitative Approach to Collaborative Learning: Performance Prediction, Individual Assessment, and Group Composition

    Science.gov (United States)

    Cen, Ling; Ruta, Dymitr; Powell, Leigh; Hirsch, Benjamin; Ng, Jason

    2016-01-01

    The benefits of collaborative learning, although widely reported, lack the quantitative rigor and detailed insight into the dynamics of interactions within the group, while individual contributions and their impacts on group members and their collaborative work remain hidden behind joint group assessment. To bridge this gap we intend to address…

  3. A review of sow and piglet behaviour and performance in group housing systems for lactating sows

    NARCIS (Netherlands)

    Nieuwamerongen, van S.E.; Bolhuis, J.E.; Peet-Schwering, van der C.M.C.; Soede, N.M.

    2014-01-01

    Commercial use of group housing systems for lactating sows is limited, but the recent transition to group housing during gestation in the EU may result in a renewed interest in such systems. Therefore, this review aims to identify key factors that may contribute to the success or failure of group

  4. Blending Individual and Group Assessment: A Model for Measuring Student Performance

    Science.gov (United States)

    Reiser, Elana

    2017-01-01

    Two sections of a college discrete mathematics class were taught using cooperative learning techniques throughout the semester. The 33 students attending these sections were randomly assigned into groups of three. Their final examination consisted of an individual and group blended examination where students worked in their groups and discussed…

  5. Midwives' experiences of performing maternal observations and escalating concerns: a focus group study.

    Science.gov (United States)

    Jeffery, Justine; Hewison, Alistair; Goodwin, Laura; Kenyon, Sara

    2017-09-02

    For the past decade, Maternal Mortality Reports, published in the United Kingdom every three years, have consistently raised concerns about maternal observations in maternity care. The reports identify that observations are not being done, not being completed fully, are not recorded on Early Warning Score systems, and/or are not escalated appropriately. This has resulted in delays in referral, intervention and increases the risk of maternal morbidity or mortality. However there has been little exploration of the possible reasons for non-completion of maternal observations. The aim of this study was to explore midwives' experiences of performing maternal observations and escalating concerns in rural and urban maternity settings in the West Midlands of England. A qualitative design involving a series of six focus groups with midwives and Supervisors of Midwives was employed to investigate the facilitators of, and barriers to the completion of maternal observations. Eighteen Midwives and 8 Supervisors of Midwives participated in a total of 6 focus groups. Three key themes emerged from the data: (1) Organisation of Maternal Observations (including delegation of tasks to Midwifery Support Workers, variation in their training, the care model used e.g. one to one care, and staffing issues); (2) Prioritisation of Maternal Observations (including the role of professional judgement and concerns expressed by midwives that they did not feel equipped to care for women with complex clinical needs; and (3) Negotiated Escalation (including the inappropriate response from senior staff to use of Modified Early Warning Score systems, and the emotional impact of escalation). A number of organisational and cultural barriers exist to the completion of maternal observations and the escalation of concerns. In order to address these the following actions are recommended: standardised training for Midwifery Support Workers, review of training of midwives to ensure it addresses the

  6. METODE ACTIVE ISOLATED STRETCHING (AIS DAN METODE HOLD RELAX STRETCHING (HRS SAMA EFEKTIF DALAM MENINGKATKAN FLEKSIBILITAS OTOT HAMSTRING PADA MAHASISWA AKADEMI FISIOTERAPI WIDYA HUSADA SEMARANG YANG MENGALAMI HAMSTRING MUSCLE TIGHTNESS (HMTs

    Directory of Open Access Journals (Sweden)

    Akhmad alfajri

    2015-08-01

    Full Text Available Students with Hamstring Muscle Tightness (HMTs will be at risk of Anterior Crusiatum Ligament (ACL, Low Back Pain (LBP and also Plantar Faciitis. One of the efforts to reduce tightness and improve hamstring muscle flexibility is stretching. Active Isolated Stretching (AIS and Hold Relax Stretching (HRS are the methods of influential stretching to improve muscle flexibility. The goal of the research is to prove that AIS method is equally effective with the HRS method to improve hamstring muscle flexibility to the HMTs patients. The research method was true experimental with pre and post test group design. The research was conducted for 3 weeks and the samples are 23 students in range of 18-25 years old students of physical therapy in Physical Therapy Academy of Widya Husada Semarang which divided into 2 groups; AIS group (n= 12 and HRS group (n= 11. The research used Sit and Reach Test (SRT as the measurement instrument. The result of the research was the average result of AIS group used SRT before treatment was 1.75 cm, SB= 4.309 and after treatment was 10. 58 cm, SB = 8. 005 within p= 0.000 (p 0.05. Those explain that the improvement of hamstring muscle flexibility to the two groups does not show any significant difference. Conclusion from this study was active isolated stretching method and hold relax stretching method are equally effective to improving muscle flexibility of hamstring muscle tightness students of physical therapy in Physical Therapy Academy of Widya Husada Semarang.

  7. The Effect of Anabolic Steroid Administration on Passive Stretching-Induced Expression of Mechano-Growth Factor in Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Satoshi Ikeda

    2013-01-01

    Full Text Available Background. Stretching of skeletal muscle induces expression of the genes which encode myogenic transcription factors or muscle contractile proteins and results in muscle growth. Anabolic steroids are reported to strengthen muscles. We have previously studied the effects of muscle stretching on gene expression. Here, we studied the effect of a combination of passive stretching and the administration of an anabolic steroid on mRNA expression of a muscle growth factor, insulin-like growth factor-I autocrine variant, or mechano-growth factor (MGF. Methods. Twelve 8-week-old male Wistar rats were used. Metenolone was administered and passive repetitive dorsiflexion and plantar flexion of the ankle joint performed under deep anesthesia. After 24 h, the gastrocnemius muscles were removed and the mRNA expression of insulin-like growth factor-I autocrine variant was measured using quantitative real-time polymerase chain reaction. Results. Repetitive stretching in combination with metenolone, but not stretching alone, significantly increased MGF mRNA expression. Conclusion. Anabolic steroids enhance the effect of passive stretching on MGF expression in skeletal muscle.

  8. Effect of hip and knee position on tensor fasciae latae elongation during stretching: An ultrasonic shear wave elastography study.

    Science.gov (United States)

    Umehara, Jun; Ikezoe, Tome; Nishishita, Satoru; Nakamura, Masatoshi; Umegaki, Hiroki; Kobayashi, Takuya; Fujita, Kosuke; Ichihashi, Noriaki

    2015-12-01

    Decreased flexibility of the tensor fasciae latae is one factor that causes iliotibial band syndrome. Stretching has been used to improve flexibility or tightness of the muscle. However, no studies have investigated the effective stretching position for the tensor fasciae latae using an index to quantify muscle elongation in vivo. The aim of this study was to investigate the effects of hip rotation and knee angle on tensor fasciae latae elongation during stretching in vivo using ultrasonic shear wave elastography. Twenty healthy men participated in this study. The shear elastic modulus of the tensor fasciae latae was calculated using ultrasonic shear wave elastography. Stretching was performed at maximal hip adduction and maximal hip extension in 12 different positions with three hip rotation conditions (neutral, internal, and external rotations) and four knee angles (0°, 45°, 90°, and 135°). Two-way analysis of variance showed a significant main effect for knee angle, but not for hip rotation. The post-hoc test for knee angle indicated that the shear elastic modulus at 90° and 135° were significantly greater than those at 0° and 45°. Our results suggest that adding hip rotation to the stretching position with hip adduction and extension may have less effect on tensor fasciae latae elongation, and that stretching at >90° of knee flexion may effectively elongate the tensor fasciae latae. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Structural Transitions in Supercoiled Stretched DNA

    Science.gov (United States)

    v, Croquette

    1998-03-01

    Using magnetic micromanipulation techniques [Strick 96]( uc(T.R.) Strick, J.-F. Allemand, D. Bensimon, A. Bensimon) and uc(V.) Croquette, "The elasticity of a single supercoiled DNA molecule", Science, 271, 1835 (1996)., we have studied the mechanical properties (force versus extension) of single DNA molecules under a wide range of torsional stresses (supercoiling). We show that unwinding the DNA double helix leads to a phase separation between regular B-DNA and denaturation bubbles. The fraction of denatured molecule increases linearly with the degree of unwinding, beginning at a value of 1% unwinding. We have confirmed this denatured state by hybridization of homologous single-stranded DNA probes and by a chemical attack of the exposed bases. Surprisingly, when we overwind the molecule, the elasticity curves we obtain may also be interpreted by the coexistence of two phases, B-DNA and a new phase which we note P-DNA. The fraction of this new phase increases smoothly with overwinding, beginning at 3 % and continuing up to 300 %. Our results indicate that this new phase is four times more twisted that the standard B-DNA and is 1.75 times longer. Although the structure of this phase is not yet known, such a high twisting can only be attained if the sugar-phosphate backbones of the two strands are twisted closely while the bases are expelled outside of the molecule's core, in a structure reminiscent of the one proposed by Pauling. Indeed we have shown that this new phase is sensitive to chemical attack whereas the B-DNA is not. This new phase begins to appear on a molecule overwound by 3 % and stretched by a force of 5 pN, conditions typically encountered in vivo during gene transcription. This new phase may thus play a biological role (for more details).

  10. Magnitude and duration of stretch modulate fibroblast remodeling.

    Science.gov (United States)

    Balestrini, Jenna L; Billiar, Kristen L

    2009-05-01

    Mechanical cues modulate fibroblast tractional forces and remodeling of extracellular matrix in healthy tissue, healing wounds, and engineered matrices. The goal of the present study is to establish dose-response relationships between stretch parameters (magnitude and duration per day) and matrix remodeling metrics (compaction, strength, extensibility, collagen content, contraction, and cellularity). Cyclic equibiaxial stretch of 2-16% was applied to fibroblast-populated fibrin gels for either 6 h or 24 h/day for 8 days. Trends in matrix remodeling metrics as a function of stretch magnitude and duration were analyzed using regression analysis. The compaction and ultimate tensile strength of the tissues increased in a dose-dependent manner with increasing stretch magnitude, yet remained unaffected by the duration in which they were cycled (6 h/day versus 24 h/day). Collagen density increased exponentially as a function of both the magnitude and duration of stretch, with samples stretched for the reduced duration per day having the highest levels of collagen accumulation. Cell number and failure tension were also dependent on both the magnitude and duration of stretch, although stretch-induced increases in these metrics were only present in the samples loaded for 6 h/day. Our results indicate that both the magnitude and the duration per day of stretch are critical parameters in modulating fibroblast remodeling of the extracellular matrix, and that these two factors regulate different aspects of this remodeling. These findings move us one step closer to fully characterizing culture conditions for tissue equivalents, developing improved wound healing treatments and understanding tissue responses to changes in mechanical environments during growth, repair, and disease states.

  11. Acute effects of short and long duration dynamic stretching protocols on muscle strength

    Directory of Open Access Journals (Sweden)

    Christiano Francisco dos Santos

    Full Text Available Objective Compare the acute effects of dynamic stretching protocols on the isokinetic performance of the quadriceps and hamstring muscles at two velocities in adult males.Methodology Included the participation of 14 males (21 ± 2.6 years; 178 ± 0.4 cm; 73.2 ± 20.9 kg were assessed using an isokinetic dynamometer before and after following a short or long-duration dynamic stretching protocol or a control protocol. The results were assessed by a two-way ANOVA and a Scheffé’s post hoc test at a 5% significance level.Results No difference was found in the variables assessed at 180°/s after LDDS. At 60°/s, LDDS reduced the power of the knee flexors. The control protocol reduced the power of the knee flexors and increased the power of the extensors. At 60°/s, the work of the knee flexors exhibited a reduction after LDDS. The control protocol resulted in a reduction in the work of the flexors. The peak torque angle exhibited a reduction in the extensors and flexors after LDDS and SDDS.Conclusion Dynamic stretching did not cause any change in the peak torque, which points to its possible use in activities involving velocity and muscle strength. The executing dynamic stretching before physical activities such as running and high-intensity sports might be beneficial by promoting increases in heart rate and in body temperature.

  12. Stretching of Active Muscle Elicits Chronic Changes in Multiple Strain Risk Factors.

    Science.gov (United States)

    Kay, Anthony David; Richmond, Dominic; Talbot, Chris; Mina, Minas; Baross, Anthony William; Blazevich, Anthony John

    2016-07-01

    The muscle stretch intensity imposed during "flexibility" training influences the magnitude of joint range of motion (ROM) adaptation. Thus, stretching while the muscle is voluntarily activated was hypothesized to provide a greater stimulus than passive stretching. The effect of a 6-wk program of stretch imposed on an isometrically contracting muscle (i.e., qualitatively similar to isokinetic eccentric training) on muscle-tendon mechanics was therefore studied in 13 healthy human volunteers. Before and after the training program, dorsiflexion ROM, passive joint moment, and maximal isometric plantarflexor moment were recorded on an isokinetic dynamometer. Simultaneous real-time motion analysis and ultrasound imaging recorded gastrocnemius medialis muscle and Achilles tendon elongation. Training was performed twice weekly and consisted of five sets of 12 maximal isokinetic eccentric contractions at 10°·s. Significant increases (P tendon stiffness) was detected (-1.5%, P > 0.05), a significant increase in tendon stiffness (31.2%, P tendon stiffness simultaneous with significant increases in tendon stiffness and decreases in passive muscle stiffness indicates that tissue-specific effects were elicited.

  13. The Relationship of Individual Difference and Group Process Variables with Self-Managed Team Performance: A Field Investigation

    National Research Council Canada - National Science Library

    Jordan, Mark

    2001-01-01

    The efficacy of dispositional individual difference team composition and group process variables in explaining team performance was examined for 1,030 military officers working in 92 teams over a 5-week period...

  14. A Review and Annotated Bibliography of the Literature Pertaining to Team and Small Group Performance (1989 to 1999)

    National Research Council Canada - National Science Library

    LaJoie, Andrew

    1999-01-01

    .... Training and military doctrine has been evolving to reflect this emphasis on teamwork. The purpose of this annotated bibliography is to review literature published over the last ten years concerning team and small group performance...

  15. Characterizing the stretch-flangeability of hot rolled multiphase steels

    International Nuclear Information System (INIS)

    Pathak, N.; Butcher, C.; Worswick, M.; Gao, J.

    2013-01-01

    Hole expansion tests are commonly used to characterize the edge stretching limit of a material. Traditionally, a conical punch is used to expand a punched hole until a through-thickness crack appears. However, many automotive stretch flanging operations involve in-plane edge stretching that is best captured with a flat punch. In this paper, hole expansion tests were carried out on two different hot-rolled multiphase steels using both flat and conical punches. The fracture mechanisms for both punch types were investigated using scanning electron microscopy (SEM)

  16. Improving the performance of indicator groups for the identification of important areas for species conservation

    DEFF Research Database (Denmark)

    Larsen, Frank Wugt; Bladt, Jesper; Rahbek, Carsten

    2007-01-01

    Indicator groups may be important tools with which to guide the selection of networks of areas for conservation. Nevertheless, the literature provides little guidance as to what makes some groups of species more suitable than others to guide area selection. Using distributional data on all sub...... diversity by systematically varying the number of distinct genera and families within the indicator groups. We selected area networks based on the indicator groups and tested their ability to represent a set of species, which, in terms of species composition, is independent of the indicator group....... Increasing the proportion of threatened, endemic, and range-restricted species in the indicator groups improved effectiveness of the selected area networks; in particular it improved the effectiveness in representing other threatened and range-restricted species. In contrast increasing the proportion...

  17. Torsion-inversion tunneling patterns in the CH-stretch vibrationally excited states of the G12 family of molecules including methylamine.

    Science.gov (United States)

    Dawadi, Mahesh B; Bhatta, Ram S; Perry, David S

    2013-12-19

    Two torsion-inversion tunneling models (models I and II) are reported for the CH-stretch vibrationally excited states in the G12 family of molecules. The torsion and inversion tunneling parameters, h(2v) and h(3v), respectively, are combined with low-order coupling terms involving the CH-stretch vibrations. Model I is a group theoretical treatment starting from the symmetric rotor methyl CH-stretch vibrations; model II is an internal coordinate model including the local-local CH-stretch coupling. Each model yields predicted torsion-inversion tunneling patterns of the four symmetry species, A, B, E1, and E2, in the CH-stretch excited states. Although the predicted tunneling patterns for the symmetric CH-stretch excited state are the same as for the ground state, inverted tunneling patterns are predicted for the asymmetric CH-stretches. The qualitative tunneling patterns predicted are independent of the model type and of the particular coupling terms considered. In model I, the magnitudes of the tunneling splittings in the two asymmetric CH-stretch excited states are equal to half of that in the ground state, but in model II, they differ when the tunneling rate is fast. The model predictions are compared across the series of molecules methanol, methylamine, 2-methylmalonaldehyde, and 5-methyltropolone and to the available experimental data.

  18. Modeling and performance analysis of movement-based group location management using RFID sensing in public transportation systems.

    Science.gov (United States)

    Chung, Yun Won

    2012-11-22

    Location management, which consists of location registration and paging, is essential to provide mobile communication services to mobile stations (MSs). Since MSs riding on a public transportation system (TS) generates significant location registration signaling loads simultaneously when a TS with riding MSs moves between location areas (LAs), group location management was proposed. Under the group location management, an MS performs group registration when it gets on a TS and performs group deregistration when it gets off a TS. Then, only a TS updates its current location when it changes LA, on behalf of all riding MSs. In this paper, movement-based group location management using radio frequency identification (RFID) is proposed, where the MS's getting on and getting off behaviors are detected using RFID and only location update of a TS is carried out if the number of crossed cells from the last updated cell exceeds a predefined movement threshold, on behalf of all riding MSs. Then, we develop an analytical model for the performance analysis of the movement-based group location management and analyze the effects of various parameters on the performance. The results show that the movement-based group location management has reduced signaling cost compared with movement-based individual location management, and optimal performance can be achieved by choosing appropriate movement threshold values.

  19. The role of individualism and the Five-Factor Model in the prediction of performance in a leaderless group discussion.

    Science.gov (United States)

    Waldman, David A; Atwater, Leanne E; Davidson, Ronald A

    2004-02-01

    Personality has seen a resurgence in the work performance literature. The Five-Factor Model (FFM) represents a set of personality factors that has received the most attention in recent years. Despite its popularity, the FFM may not be sufficiently comprehensive to account for relevant variation across performance dimensions or tasks. Accordingly, the present study also considers how individualism may predict additional variance in performance beyond the FFM. The study involved 152 undergraduate students who experienced a leaderless group discussion (LGD) exercise. Results showed that while the FFM accounted for variance in students' LGD performance, individualism (independence) accounted for additional, unique variance. Furthermore, analyses of the group compositions revealed curvilinear relationships between the relative amount of extraversion, conscientiousness, and individualism in relation to group-level performance.

  20. 40 CFR 63.138 - Process wastewater provisions-performance standards for treatment processes managing Group 1...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Process wastewater provisions-performance standards for treatment processes managing Group 1 wastewater streams and/or residuals removed from Group 1 wastewater streams. 63.138 Section 63.138 Protection of Environment ENVIRONMENTAL...

  1. Effect of Stretching Combined With Ultrashort Wave Diathermy on Joint Function and Its Possible Mechanism in a Rabbit Knee Contracture Model.

    Science.gov (United States)

    Zhang, Quan Bing; Zhou, Yun; Zhong, Hua Zhang; Liu, Yi

    2018-05-01

    The aim of this study was to investigate the therapeutic effect of stretching combined with ultrashort wave on joint contracture and explore its possible mechanism. Thirty-two rabbits underwent unilateral immobilization of a knee joint at full extension to cause joint contracture. At 6 wks after immobilization, the rabbits were randomly divided into the following four groups: natural recovery group, stretching treatment group, ultrashort wave treatment group, and combined treatment group. For comparison, eight control group animals of corresponding age were also examined. The effect of stretching and ultrashort wave treatment on joint contracture was assessed by measuring the joint range of motion, evaluating the collagen deposition of joint capsule and assessing the mRNA and protein levels for transforming growth factor β1 in the joint capsule. The combined treatment group led to the best recovery of joint function. The combined treatment with stretching and ultrashort wave was more effective than stretching or ultrashort wave treatment alone against the synovial thickening of suprapatellar joint capsule, the collagen deposition of anterior joint capsule, and the elevated expression of transforming growth factor β1 in the joint capsule. Stretching combined with ultrashort wave treatment was effective in improving joint range of motion, reducing the biomechanical, histological, and molecular manifestations of joint capsule fibrosis in a rabbit model of extending joint contracture.

  2. The effects of individual status and group performance on network ties among teammates in the National Basketball Association.

    Directory of Open Access Journals (Sweden)

    Jeremy Koster

    Full Text Available For individuals, status is derived both from their personal attributes and the groups with whom they are affiliated. Depending on the performance of their groups, the status of individuals may benefit or suffer from identifying closely with the group. When the group excels, high-status members potentially receive much of the credit and increased status. Conversely, high-status members of underperforming groups potentially suffer disproportionate declines in their status relative to the low-status group members. We therefore predict an interaction between group performance and individual status on the willingness to associate with the group and its members. We test our prediction by examining social media ties among teammates in the National Basketball Association. Specifically, we investigate the "following" ties of teammates on Twitter at the end of the 2014-2015 season. Elections to All-Star games are used to measure the status of players, and team performance is measured by recent success in the postseason playoffs. The results show that compared to high-status players on successful teams, high-status players on underperforming teams are less likely to follow their teammates. This result aligns with research on status inconsistency, suggesting that individuals deemphasize their group affiliation when it jeopardizes their individual status. An additional contribution is the advancement of the probit Social Relations Model for the analysis of binary ties in social networks.

  3. The effects of individual status and group performance on network ties among teammates in the National Basketball Association.

    Science.gov (United States)

    Koster, Jeremy; Aven, Brandy

    2018-01-01

    For individuals, status is derived both from their personal attributes and the groups with whom they are affiliated. Depending on the performance of their groups, the status of individuals may benefit or suffer from identifying closely with the group. When the group excels, high-status members potentially receive much of the credit and increased status. Conversely, high-status members of underperforming groups potentially suffer disproportionate declines in their status relative to the low-status group members. We therefore predict an interaction between group performance and individual status on the willingness to associate with the group and its members. We test our prediction by examining social media ties among teammates in the National Basketball Association. Specifically, we investigate the "following" ties of teammates on Twitter at the end of the 2014-2015 season. Elections to All-Star games are used to measure the status of players, and team performance is measured by recent success in the postseason playoffs. The results show that compared to high-status players on successful teams, high-status players on underperforming teams are less likely to follow their teammates. This result aligns with research on status inconsistency, suggesting that individuals deemphasize their group affiliation when it jeopardizes their individual status. An additional contribution is the advancement of the probit Social Relations Model for the analysis of binary ties in social networks.

  4. High performance oligomers: synthesis and photochemical properties of calix(n)arene containing various photoreactive groups

    International Nuclear Information System (INIS)

    Nishikubo, T.; Kameyama, A.

    1999-01-01

    Photoreactive calix(n)arenes containing radical polymerizable (meth)acrylate groups, and catatonically polymerizable vinyl ether, propargyl ether, oxirane and oxetane groups were synthesized by certain reactions of calix(n)arenes with the corresponding (meth)acrylic acid derivatives, vinyl ether compound, epibromohydrin and oxetane derivatives, respectively. The photochemical reaction of these calix(n)arene derivatives were also examined

  5. Impact of Collaborative Tools Utilization on Group Performance in University Students

    Science.gov (United States)

    Hidayanto, Achmad Nizar; Setyady, Stella Tantra

    2014-01-01

    Nowadays the growth of technology influences the changes in group collaboration's process either for the professional or for the students. The requirement of interaction in group collaboration while doing task forces the students to schedule their meeting in order to finish the task given. So the technology starts to influence the process of group…

  6. Singapore Education Sector Analysis: Improvement and Challenges in Academic Performance of Four Ethnic Groups in Singapore.

    Science.gov (United States)

    Yamashita, Mika

    Singapore is a multi-ethnic nation-state with the following ethnic groups: Chinese (76.8%), Malay (13.9%), Indian (7.9%), and Others (1.4%) such as Eurasians, Europeans, Arabs, Jews, and Japanese. A bilingual policy, which takes English as a lingua franca and Mandarin, Malay, and Tamil as mother tongue for each ethnic group, reflects this…

  7. The effect of varying plyometric volume on stretch-shortening cycle capability in collegiate male rugby players.

    Science.gov (United States)

    Jeffreys, Mark; De Ste Croix, Mark; Lloyd, Rhodri S; Oliver, Jon L; Hughes, Jonathan

    2017-03-25

    The purpose of this study was to identify the effectiveness of low and high volume plyometric loads on developing stretch shortening cycle capability in collegiate rugby players. A between- group repeated measures design was used. Thirty six subjects (age 20.3 ±1.6 yrs, mass 91.63 ±10.36kg, stature 182.03 ±5.24cm) were randomly assigned to one of three groups, a control group (CG), a low volume plyometric group (LPG) or a high volume plyometric group (HPG). Data were collected from a force plate, and measures of reactive strength index (RSI) and leg stiffness were calculated from jump height, contact time and flight time. A significant between group × time (F = 4.01, P plyometric program. The low volume program elicited the same performance improvement in RSI as a high volume program whilst undertaking a lower dose. This suggests that strength and conditioning coaches may be able to benefit from the ability to develop more time efficient and effective plyometric programs.

  8. Optimal stretching in the reacting wake of a bluff body.

    Science.gov (United States)

    Wang, Jinge; Tithof, Jeffrey; Nevins, Thomas D; Colón, Rony O; Kelley, Douglas H

    2017-12-01

    We experimentally study spreading of the Belousov-Zhabotinsky reaction behind a bluff body in a laminar flow. Locations of reacted regions (i.e., regions with high product concentration) correlate with a moderate range of Lagrangian stretching and that range is close to the range of optimal stretching previously observed in topologically different flows [T. D. Nevins and D. H. Kelley, Phys. Rev. Lett. 117, 164502 (2016)]. The previous work found optimal stretching in a closed, vortex dominated flow, but this article uses an open flow and only a small area of appreciable vorticity. We hypothesize that optimal stretching is common in advection-reaction-diffusion systems with an excitation threshold, including excitable and bistable systems, and that the optimal range depends on reaction chemistry and not on flow shape or characteristic speed. Our results may also give insight into plankton blooms behind islands in ocean currents.

  9. Effects of Static Stretching and Playing Soccer on Knee Laxity

    NARCIS (Netherlands)

    Baumgart, Christian; Gokeler, Alli; Donath, Lars; Hoppe, Matthias W.; Freiwald, Juergen

    Objective: This study investigated exercise-induced effects of static stretching and playing soccer on anterior tibial translation (ATT) of the knee joint. Design: Randomized controlled trial. Setting: University biomechanics laboratory. Participants: Thirty-one athletes were randomly assigned into

  10. Effects of Static Stretching and Playing Soccer on Knee Laxity

    NARCIS (Netherlands)

    Baumgart, Christian; Gokeler, Alli; Donath, Lars; Hoppe, Matthias W.; Freiwald, Juergen

    2015-01-01

    Objective: This study investigated exercise-induced effects of static stretching and playing soccer on anterior tibial translation (ATT) of the knee joint. Design: Randomized controlled trial. Setting: University biomechanics laboratory. Participants: Thirty-one athletes were randomly assigned into

  11. Damage percolation during stretch flange forming of aluminum alloy sheet

    Science.gov (United States)

    Chen, Zengtao; Worswick, Michael J.; Keith Pilkey, A.; Lloyd, David J.

    2005-12-01

    A multi-scale finite element (FE)-damage percolation model was employed to simulate stretch flange forming of aluminum alloys AA5182 and AA5754. Material softening and strain gradients were captured using a Gurson-based FE model. FE results were then fed into the so-called damage percolation code, from which the damage development was modelled within measured microstructures. The formability of the stretch flange samples was predicted based upon the onset of catastrophic failure triggered by profuse void coalescence within the measured second-phase particle field. Damage development is quantified in terms of crack and void areal fractions, and compared to metallographic results obtained from interrupted stretch flange specimens. Parametric study is conducted on the effect of void nucleation strain in the prediction of formability of stretch flanges to "calibrate" proper nucleation strains for both alloys.

  12. Stretched flow of Carreau nanofluid with convective boundary ...

    Indian Academy of Sciences (India)

    journal of. January 2016 physics pp. 3–17. Stretched flow of Carreau nanofluid with ... fluid over a flat plate subjected to convective surface condition. ... the steady laminar boundary layer flow over a permeable plate with a convective boundary.

  13. Vertical interlocks of executives and performance of affiliated firms in state owned Chinese business groups

    DEFF Research Database (Denmark)

    Arnoldi, Jakob; Chen, Xin; Na, Chaohong

    . Further, the positive effects of vertically interlocking chairmen decrease as the number of pyramidal layers increases or regional marketization index improves. Such positive effects of interlocks, however, become greater as the divergence between cash flow rights and control rights of business groups...... increases. Our findings are consistent with the hypotheses that vertically interlocking executives can increase firm value by providing better protection against political interference and expropriation by the ultimate controllers of business groups. Our study sheds new light in the role and function...... of interlocks and adds to a small body of literature on the dynamics of state owned business groups in emerging markets generally and China particularly....

  14. A Fundamental Study of Stretch-Drawing Process of Sheet Metals : Single and Double Operations

    Science.gov (United States)

    Gotoh, Manabu; Kim, Young-soo; Yamashita, Minoru

    1998-05-01

    Fundamental and informative data of axisymmetric stretch-drawing of several sheet metals with thichness of 0.7 1.0 mm are presented especially for single and double operations. Very small radius is applied to the die-profile (or -shoulder) in all operations to induce wall-thinning by the effect of bending-under-tension, from which the name `stretch-drawing' comes. It is clearly demonstrated that deeper cups could be formed by the single and double stretch-drawings from smaller cirlcular blanks due to such wall-thinning action than in the usual deep-drawing of larger blanks. From this fact, it is emphasized that the deep-drawability of a sheet metal is not evaluated simply by the conventional LDR (=limiting drawing ratio), but the depth of the drawn cup should also be taken into account. Many experimental data about various metals and thicknesses given in this paper offer a valueable information on this process for more general use which recommends to replace the conventional deep-drawing process by the stretch-drawing process both for single and double operations. In the single stretch-drawing, it is also confirmed that a deeper cup can be produced by raising the blank-holding force at later stage of operation. Fracturing is found to occur at the middle section of the wall part or at the die-profile other than at the punch profile common in the usual deep-drawing process. Numerical simulation of the single stretch-drawing process is also performed by use of DYNA-3D code to confirm that a satisfactory prediction especially in the depth of the drawn-cup can be done at least in a practical sense, although this kind of numerical analysis is very difficult because of the severity or localization of deformation around the die profile. The drawn cup of SUS304 among others fractures in a couple of weeks after the operation due to the residual circumferential tensile stress, whereas that of SUS304L does not. In the double stretch-drawing, it is confirmed that very deeper

  15. Acute effect of static stretching on muscle force in older women

    Directory of Open Access Journals (Sweden)

    André Luiz Demantova Gurjão

    2010-04-01

    Full Text Available The objective of this study was to investigate the acute effect of static stretching on the peak rate of force development (PRFD and maximum voluntary contraction (MVC in older women. Ten women (68.5 ± 7.0 years; 70.9 ± 8.1 kg; 159.4 ± 6.0 cm; body mass index: 28.0 ± 3.8 kg/m2 were studied. MVC and PRFD were determined by leg press exercise before and after the control or stretching condition (three sets of 30 seconds of static stretching of the quadriceps on two different days (interval of 24 hours. PRFD was determined as the steepest slope of the curve, calculated within regular windows of 20 milliseconds (∆force/∆time for the first 200 milliseconds after the onset of contraction. MVC was determined as the highest value recorded in each set. Only one condition was tested on each day and the order of application of each condition was determined randomly. The stretching intensity was evaluated by the muscle pain threshold. Four post-condition assessments (post-treatment, 10, 20, and 30 minutes were performed to monitor muscle strength. ANCOVA 2x5, followed by the Scheffé post-hoc test, showed no significant interactions between conditions vs. times (P > 0.05 for PRFD or MVC. In conclusion, acute bouts of static stretching of the quadriceps femoris do not affect the ability of rapid and maximum muscle force production in older women.

  16. Jack-knife stretching promotes flexibility of tight hamstrings after 4 weeks: a pilot study.

    Science.gov (United States)

    Sairyo, Koichi; Kawamura, Takeshi; Mase, Yasuyoshi; Hada, Yasushi; Sakai, Toshinori; Hasebe, Kiyotaka; Dezawa, Akira

    2013-08-01

    Tight hamstrings are reported to be one of the causes of low back pain. However, there have been few reports on effective stretching procedures for the tight hamstrings. The so-called jack-knife stretch, an active-static type of stretching, can efficiently increase the flexibility of tight hamstrings. To evaluate hamstring tightness before and after the 4-week stretching protocol in healthy volunteer adults and patients aged under 18 years with low back pain. For understanding the hamstrings tightness, we measured two parameters including (1) finger to floor distance (FFD) and (2) pelvis forward inclination angle (PFIA). Eight healthy adult volunteers who had no lumbar or hip problems participated in this study (mean age: 26.8 years). All lacked flexibility and their FFD were positive before the experiment. Subjects performed 2 sets of the jack-knife stretch every day for 4 weeks. One set consisted of 5 repetitions, each held for 5 s. Before and during the 4-week experiment, the FFD and PFIA of toe-touching tests were measured weekly. For 17 of the sports players aged under 18, only FFD was measured. In adult volunteers, FFD was 14.1 ± 6.1 cm before the experiment and decreased to -8.1 ± 3.7 cm by the end of week 4, indicating a gain in flexibility of 22.2 cm. PFIA was 50.6 ± 8.2 before the experiment and 83.8 ± 5.8 degrees after. Before and after the experiment, the differences were significant (p hamstrings.

  17. High throughput web inspection system using time-stretch real-time imaging

    Science.gov (United States)

    Kim, Chanju

    Photonic time-stretch is a novel technology that enables capturing of fast, rare and non-repetitive events. Therefore, it operates in real-time with ability to record over long period of time while having fine temporal resolution. The powerful property of photonic time-stretch has already been employed in various fields of application such as analog-to-digital conversion, spectroscopy, laser scanner and microscopy. Further expanding the scope, we fully exploit the time-stretch technology to demonstrate a high throughput web inspection system. Web inspection, namely surface inspection is a nondestructive evaluation method which is crucial for semiconductor wafer and thin film production. We successfully report a dark-field web inspection system with line scan speed of 90.9 MHz which is up to 1000 times faster than conventional inspection instruments. The manufacturing of high quality semiconductor wafer and thin film may directly benefit from this technology as it can easily locate defects with area of less than 10 microm x 10 microm where it allows maximum web flow speed of 1.8 km/s. The thesis provides an overview of our web inspection technique, followed by description of the photonic time-stretch technique which is the keystone in our system. A detailed explanation of each component is covered to provide quantitative understanding of the system. Finally, imaging results from a hard-disk sample and flexible films are presented along with performance analysis of the system. This project was the first application of time-stretch to industrial inspection, and was conducted under financial support and with close involvement by Hitachi, Ltd.

  18. Social relationships and reproductive performance in group-living arctic blue foxes

    Directory of Open Access Journals (Sweden)

    Hannu Korhonen

    1994-01-01

    Full Text Available The aim of the present work was to study social relationships and reproductivity in captive arctic blue fox groups of different genetic origin. The social status of the individuals among groups remained constant during autumn and early winter. Males typically dominated over females in the groups. Males also had higher body weights and more social contacts than females. The locomotor activity of the animals increased during the breeding season, especially in the case of males. Urinary marking had a significant importance during the breeding season, being most pronounced in dominant males. No synchronization was observed in the heat development of females despite some kinship. Behaviours such as escape attempts, bitings and increased aggressiveness occurred in March-April as a result of increasing social tension combined with reproductive behaviour. Whelping success varied depending on group composition. Some of the non-breeding and breeding females were observed to act as communal nursing helpers.

  19. Performance of an export group from the cosmetic sector: evaluating results on the companiess' perspective

    Directory of Open Access Journals (Sweden)

    Otávio Rezende

    2009-03-01

    Full Text Available The objective of this article is to analyze the results of structuring, management and sales promotion of those groups of company. Starting from a case study of the cosmetics sector, the article analyzes the initial expectation of the companies on the creation of the group, its relationship with the market and the companies’ interaction as a means of obtaining results, taking into consideration that the Brazilian external trade promotion policy has adopted the model of export groups as a strategy to boost companies’ productive capacity and to reduce promotion costs. In conclusion, the low level of confidence in the inter-firm relationship and the lack of competitiveness present themselves as determining factors for the few results achieved. The research underlines the need for working models of business cooperation in export groups and for establishing a way to measure the results expected by the companies in their internationalization process.

  20. University of Virginia High Energy Physics Group. Final performance report, June 1, 1989--January 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The US Department of Energy Contracts for 1989 covered the initial year of the University of Virginia High Energy Physics Group. The first proposal was submitted in the fall of 1988 and the first allocation of funding was received in June 1989. This first contract which covered the time period June 1, 1989--January 31, 1990 was in the amount of $186,000 and covered UVa HEP group operations and equipment during that period. At that point, a regular contract year was established and two subsequent contracts were issued for February 1, 1990--January 31, 1991 and February 1, 1991--January 31, 992 with awards of $280,000 and $580,000, respectively. The funding between June, 1989 and January, 1992 covered the activities of both the UVa Theory Group (Task A) and the UVa HEP Experimental Group (Task B). Expenditures of all above funds was completed by January 31, 1994. In this time period, certain initial things were accomplished using the operating funds provided by DOE and the seed funds ($2.2 million over the period). There were three main areas of activities, the building of the University of Virginia HEP infrastructure (construction of lab space, computer facilities, electronic shop, machine shop and office space), the hiring of personnel (faculty, post docs, and students) and the physics activities of the group. Much of the physics program of the experimental group revolved around the study of production and decay of heavy flavor. A list of technical papers generated by their work is provided.

  1. University of Virginia High Energy Physics Group. Final performance report, June 1, 1989 - January 31, 1994

    International Nuclear Information System (INIS)

    1994-01-01

    The US Department of Energy Contracts for 1989 covered the initial year of the University of Virginia High Energy Physics Group. The first proposal was submitted in the fall of 1988 and the first allocation of funding was received in June 1989. This first contract which covered the time period June 1, 1989--January 31, 1990 was in the amount of $186,000 and covered UVa HEP group operations and equipment during that period. At that point, a regular contract year was established and two subsequent contracts were issued for February 1, 1990--January 31, 1991 and February 1, 1991--January 31, 992 with awards of $280,000 and $580,000, respectively. The funding between June, 1989 and January, 1992 covered the activities of both the UVa Theory Group (Task A) and the UVa HEP Experimental Group (Task B). Expenditures of all above funds was completed by January 31, 1994. In this time period, certain initial things were accomplished using the operating funds provided by DOE and the seed funds ($2.2 million over the period). There were three main areas of activities, the building of the University of Virginia HEP infrastructure (construction of lab space, computer facilities, electronic shop, machine shop and office space), the hiring of personnel (faculty, post docs, and students) and the physics activities of the group. Much of the physics program of the experimental group revolved around the study of production and decay of heavy flavor. A list of technical papers generated by their work is provided

  2. Equibiaxial cyclic stretch stimulates fibroblasts to rapidly remodel fibrin.

    Science.gov (United States)

    Balestrini, Jenna Leigh; Billiar, Kristen Lawrence

    2006-01-01

    Understanding the effects of the mechanical environment on wound healing is critical for developing more effective treatments to reduce scar formation and contracture. The aim of this study was to investigate the effects of dynamic mechanical stretch on cell-mediated early wound remodeling independent of matrix alignment which obscures more subtle remodeling mechanisms. Cyclic equibiaxial stretch (16% stretch at 0.2 Hz) was applied to fibroblast-populated fibrin gel in vitro wound models for eight days. Compaction, density, tensile strength, and collagen content were quantified as functional measures of remodeling. Stretched samples were approximately ten times stronger, eight-fold more dense, and eight times thinner than statically cultured samples. These changes were accompanied by a 15% increase in net collagen but no significant differences in cell number or viability. When collagen crosslinking was inhibited in stretched samples, the extensibility increased and the strength decreased. The apparent weakening was due to a reduction in compaction rather than a decrease in ability of the tissue to withstand tensile forces. Interestingly, inhibiting collagen crosslinking had no measurable effects on the statically cultured samples. These results indicate that amplified cell-mediated compaction and even a slight addition in collagen content play substantial roles in mechanically induced wound strengthening. These findings increase our understanding of how mechanical forces guide the healing response in skin, and the methods employed in this study may also prove valuable tools for investigating stretch-induced remodeling of other planar connective tissues and for creating mechanically robust engineered tissues.

  3. A Bayesian Performance Prediction Model for Mathematics Education: A Prototypical Approach for Effective Group Composition

    Science.gov (United States)

    Bekele, Rahel; McPherson, Maggie

    2011-01-01

    This research work presents a Bayesian Performance Prediction Model that was created in order to determine the strength of personality traits in predicting the level of mathematics performance of high school students in Addis Ababa. It is an automated tool that can be used to collect information from students for the purpose of effective group…

  4. Quantifying stretching and rearrangement in epithelial sheet migration

    International Nuclear Information System (INIS)

    Lee, Rachel M; Nordstrom, Kerstin N; Losert, Wolfgang; Kelley, Douglas H; Ouellette, Nicholas T

    2013-01-01

    Although understanding the collective migration of cells, such as that seen in epithelial sheets, is essential for understanding diseases such as metastatic cancer, this motion is not yet as well characterized as individual cell migration. Here we adapt quantitative metrics used to characterize the flow and deformation of soft matter to contrast different types of motion within a migrating sheet of cells. Using a finite-time Lyapunov exponent (FTLE) analysis, we find that—in spite of large fluctuations—the flow field of an epithelial cell sheet is not chaotic. Stretching of a sheet of cells (i.e. positive FTLE) is localized at the leading edge of migration and increases when the cells are more highly stimulated. By decomposing the motion of the cells into affine and non-affine components using the metric D m in 2 , we quantify local plastic rearrangements and describe the motion of a group of cells in a novel way. We find an increase in plastic rearrangements with increasing cell densities, whereas inanimate systems tend to exhibit less non-affine rearrangements with increasing density. (paper)

  5. Static stretch versus Mulligan Concept – long-term effects in gymnast’s flexibility DOI:10.5007/1980-0037.2010v12n3p202

    Directory of Open Access Journals (Sweden)

    Manuela Karloh

    2010-01-01

    Full Text Available Flexibility is one of the most important physical aspects in Rhythmic Gymnastics (RG. The purpose of the study was to compare long-term changes in flexibility of hip extension in athletes of RG in function of two techniques: the static stretch and Mulligan’s Long Leg Traction. Participated eight female athletes with an average age of 13,25±0,89 years old, divided into two groups. Group1 performed Mulligan technique and Group2 performed static stretch. Flexibility training lasts for six weeks. It was executed 2 times a week, and was composed by 2 repetitions of 30 seconds for each lower limb. Photogrammetry was used to assess the range of motion (ROM of hip extension. ROM was assessed before and after six weeks of training. Descriptive and inferential statistics were used to analyze the data. The increase of ROM was statistically significant in both lower limbs in Group 1, and in right lower limb (RLL in Group 2. After six weeks of training the increase of ROM in Group 1 was 6,25°± 2,75º in left lower limb (LLL and 5,25°± 2,63º in RLL, and the increase in Group 2 was 6,75º± 4,64º in LLL and 5,5º± 3,41º in RLL. Comparing the two executed techniques, in relation to the increase of ROM, there were no statistically significant differences. We conclude that after six weeks of training the two proposed techniques have showed increases in range of motion.

  6. Use of the Web by a Distributed Research group Performing Distributed Computing

    Science.gov (United States)

    Burke, David A.; Peterkin, Robert E.

    2001-06-01

    A distributed research group that uses distributed computers faces a spectrum of challenges--some of which can be met by using various electronic means of communication. The particular challenge of our group involves three physically separated research entities. We have had to link two collaborating groups at AFRL and NRL together for software development, and the same AFRL group with a LANL group for software applications. We are developing and using a pair of general-purpose, portable, parallel, unsteady, plasma physics simulation codes. The first collaboration is centered around a formal weekly video teleconference on relatively inexpensive equipment that we have set up in convenient locations in our respective laboratories. The formal virtual meetings are augmented with informal virtual meetings as the need arises. Both collaborations share research data in a variety of forms on a secure URL that is set up behind the firewall at the AFRL. Of course, a computer-generated animation is a particularly efficient way of displaying results from time-dependent numerical simulations, so we generally like to post such animations (along with proper documentation) on our web page. In this presentation, we will discuss some of our accomplishments and disappointments.

  7. Swarm intelligence in animal groups: when can a collective out-perform an expert?

    Directory of Open Access Journals (Sweden)

    Konstantinos V Katsikopoulos

    Full Text Available An important potential advantage of group-living that has been mostly neglected by life scientists is that individuals in animal groups may cope more effectively with unfamiliar situations. Social interaction can provide a solution to a cognitive problem that is not available to single individuals via two potential mechanisms: (i individuals can aggregate information, thus augmenting their 'collective cognition', or (ii interaction with conspecifics can allow individuals to follow specific 'leaders', those experts with information particularly relevant to the decision at hand. However, a-priori, theory-based expectations about which of these decision rules should be preferred are lacking. Using a set of simple models, we present theoretical conditions (involving group size, and diversity of individual information under which groups should aggregate information, or follow an expert, when faced with a binary choice. We found that, in single-shot decisions, experts are almost always more accurate than the collective across a range of conditions. However, for repeated decisions - where individuals are able to consider the success of previous decision outcomes - the collective's aggregated information is almost always superior. The results improve our understanding of how social animals may process information and make decisions when accuracy is a key component of individual fitness, and provide a solid theoretical framework for future experimental tests where group size, diversity of individual information, and the repeatability of decisions can be measured and manipulated.

  8. Association between quality management and performance indicators in Dutch diabetes care groups: a cross-sectional study.

    Science.gov (United States)

    Campmans-Kuijpers, Marjo J E; Baan, Caroline A; Lemmens, Lidwien C; Klomp, Maarten L H; Romeijnders, Arnold C M; Rutten, Guy E H M

    2015-05-11

    To enhance the quality of diabetes care in the Netherlands, so-called care groups with three to 250 general practitioners emerged to organise and coordinate diabetes care. This introduced a new quality management level in addition to the quality management of separate general practices. We hypothesised that this new level of quality management might be associated with the aggregate performance indicators on the patient level. Therefore, we aimed to explore the association between quality management at the care group level and its aggregate performance indicators. A cross-sectional study. All Dutch care groups (n=97). 23 care groups provided aggregate register-based performance indicators of all their practices as well as data on quality management measured with a questionnaire filled out by 1 or 2 of their quality managers. The association between quality management, overall and in 6 domains ('organisation of care', 'multidisciplinary teamwork', 'patient centredness', 'performance management', 'quality improvement policy' and 'management strategies') on the one hand and 3 process indicators (the percentages of patients with at least 1 measurement of glycated haemoglobin, lipid profile and systolic blood pressure), and 3 intermediate outcome indicators (the percentages of patients with glycated haemoglobin below 53 mmol/mol (7%); low-density lipoprotein cholesterol below 2.5 mmol/L; and systolic blood pressure below 140 mm Hg) by weighted univariable linear regression. The domain 'management strategies' was significantly associated with the percentage of patients with a glycated haemoglobin quality management were not associated with aggregate process or outcome indicators. This first exploratory study on quality management showed weak or no associations between quality management of diabetes care groups and their performance. It remains uncertain whether this second layer on quality management adds to better quality of care. Published by the BMJ Publishing

  9. Effect of Group Setting on Gross Motor Performance in Children 3-5 Years Old with Motor Delays.

    Science.gov (United States)

    Fay, Deanne; Wilkinson, Tawna; Wagoner, Michelle; Brooks, Danna; Quinn, Lauren; Turnell, Andrea

    2017-02-01

    The purpose of this study was to evaluate differences in gross motor performance of children 3-5 years of age with motor delays when assessed individually compared to assessment in a group setting among peers with typical development (TD). Twenty children with motor delays and 42 children with TD were recruited from a preschool program. A within-subject repeated measures design was used; each child with delay was tested both in an individual setting and in a group setting with two to four peers with TD. Testing sessions were completed 4-8 days apart. Ten different motor skills from the Peabody Developmental Motor Scales-2 were administered. Performance of each item was videotaped and scored by a blinded researcher. Overall gross motor performance was significantly different (p < .05) between the two settings, with 14 of 20 children demonstrating better performance in the group setting. In particular, children performed better on locomotion items (p < .05). The higher scores for locomotion in the group setting may be due to the influence of competition, motivation, or modeling. Assessing a child in a group setting is recommended as part of the evaluation process.

  10. Does the medium matter? The interaction of task type and technology on group performance and member reactions.

    Science.gov (United States)

    Straus, S G; McGrath, J E

    1994-02-01

    The authors investigated the hypothesis that as group tasks pose greater requirements for member interdependence, communication media that transmit more social context cues will foster group performance and satisfaction. Seventy-two 3-person groups of undergraduate students worked in either computer-mediated or face-to-face meetings on 3 tasks with increasing levels of interdependence: an idea-generation task, an intellective task, and a judgment task. Results showed few differences between computer-mediated and face-to-face groups in the quality of the work completed but large differences in productivity favoring face-to-face groups. Analysis of productivity and of members' reactions supported the predicted interaction of tasks and media, with greater discrepancies between media conditions for tasks requiring higher levels of coordination. Results are discussed in terms of the implications of using computer-mediated communications systems for group work.

  11. The Effects of Machine Load Sitnations on Performance of Job Shop and Group Scheduling

    OpenAIRE

    Torkul, O.

    2018-01-01

    Perfonnance of job shop and group scheduling ndermulti­natch work input environment was exarnined against two nachine load (light and high load) situations. n order to conduct the analysis, a deterministic computer ;im ulation program was written and used. A job shop {JS) model is applied to the shop floor area and :ompared with a simulation of a similar proposal except hat group technology (GT) model was used in the shop loor area instead. )etailed analysis of the results from applying diffe...

  12. The Effects of Machine Load Sitnations on Performance of Job Shop and Group Scheduling

    OpenAIRE

    O.TORKUL TORKUL

    1998-01-01

    Perfonnance of job shop and group scheduling ndermulti­natch work input environment was exarnined against two nachine load (light and high load) situations. n order to conduct the analysis, a deterministic computer ;im ulation program was written and used. A job shop {JS) model is applied to the shop floor area and :ompared with a simulation of a similar proposal except hat group technology (GT) model was used in the shop loor area instead. )etailed analysis of the results from applying diffe...

  13. Formal and Informal Work Group Relationships With Performance: A Moderation Model Using Social

    National Research Council Canada - National Science Library

    Knost, Benjamin R

    2006-01-01

    .... This field study, conducted at a military training course, attempted to further refine this social network-performance relationship by modeling characteristics of both the formal and informal work...

  14. Mechanical Stretching Promotes Skin Tissue Regeneration via Enhancing Mesenchymal Stem Cell Homing and Transdifferentiation.

    Science.gov (United States)

    Liang, Xiao; Huang, Xiaolu; Zhou, Yiwen; Jin, Rui; Li, Qingfeng

    2016-07-01

    Skin tissue expansion is a clinical procedure for skin regeneration to reconstruct cutaneous defects that can be accompanied by severe complications. The transplantation of mesenchymal stem cells (MSCs) has been proven effective in promoting skin expansion and helping to ameliorate complications; however, systematic understanding of its mechanism remains unclear. MSCs from luciferase-Tg Lewis rats were intravenously transplanted into a rat tissue expansion model to identify homing and transdifferentiation. To clarify underlying mechanisms, a systematic approach was used to identify the differentially expressed genes between mechanically stretched human MSCs and controls. The biological significance of these changes was analyzed through bioinformatic methods. We further investigated genes and pathways of interest to disclose their potential role in mechanical stretching-induced skin regeneration. Cross sections of skin samples from the expanded group showed significantly more luciferase(+) and stromal cell-derived factor 1α (SDF-1α)(+), luciferase(+)keratin 14(+), and luciferase(+)CD31(+) cells than the control group, indicating MSC transdifferentiation into epidermal basal cells and endothelial cells after SDF-1α-mediated homing. Microarray analysis suggested upregulation of genes related to hypoxia, vascularization, and cell proliferation in the stretched human MSCs. Further investigation showed that the homing of MSCs was blocked by short interfering RNA targeted against matrix metalloproteinase 2, and that mechanical stretching-induced vascular endothelial growth factor A upregulation was related to the Janus kinase/signal transducer and activator of transcription (Jak-STAT) and Wnt signaling pathways. This study determines that mechanical stretching might promote skin regeneration by upregulating MSC expression of genes related to hypoxia, vascularization, and cell proliferation; enhancing transplanted MSC homing to the expanded skin; and

  15. Finite Element Modeling of Reheat Stretch Blow Molding of PET

    Science.gov (United States)

    Krishnan, Dwarak; Dupaix, Rebecca B.

    2004-06-01

    Poly (ethylene terephthalate) or PET is a polymer used as a packaging material for consumer products such as beverages, food or other liquids, and in other applications including drawn fibers and stretched films. Key features that make it widely used are its transparency, dimensional stability, gas impermeability, impact resistance, and high stiffness and strength in certain preferential directions. These commercially useful properties arise from the fact that PET crystallizes upon deformation above the glass transition temperature. Additionally, this strain-induced crystallization causes the deformation behavior of PET to be highly sensitive to processing conditions. It is thus crucial for engineers to be able to predict its performance at various process temperatures, strain rates and strain states so as to optimize the manufacturing process. In addressing these issues; a finite element analysis of the reheat blow molding process with PET has been carried out using ABAQUS. The simulation employed a constitutive model for PET developed by Dupaix and Boyce et al.. The model includes the combined effects of molecular orientation and strain-induced crystallization on strain hardening when the material is deformed above the glass transition temperature. The simulated bottles were also compared with actual blow molded bottles to evaluate the validity of the simulation.

  16. Towards clinical application of RayStretch for heterogeneity corrections in LDR permanent 125I prostate brachytherapy.

    Science.gov (United States)

    Hueso-González, Fernando; Ballester, Facundo; Perez-Calatayud, Jose; Siebert, Frank-André; Vijande, Javier

    RayStretch is a simple algorithm proposed for heterogeneity corrections in low-dose-rate brachytherapy. It is built on top of TG-43 consensus data, and it has been validated with Monte Carlo (MC) simulations. In this study, we take a real clinical prostate implant with 71 125 I seeds as reference and we apply RayStretch to analyze its performance in worst-case scenarios. To do so, we design two cases where large calcifications are located in the prostate lobules. RayStretch resilience under various calcification density values is also explored. Comparisons against MC calculations are performed. Dose-volume histogram-related parameters like prostate D 90 , rectum D 2cc , or urethra D 10 obtained with RayStretch agree within a few percent with the detailed MC results for all cases considered. The robustness and compatibility of RayStretch with commercial treatment planning systems indicate its applicability in clinical practice for dosimetric corrections in prostate calcifications. Its use during intraoperative ultrasound planning is foreseen. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  17. Evaluating Equating Accuracy and Assumptions for Groups that Differ in Performance

    Science.gov (United States)

    Powers, Sonya; Kolen, Michael J.

    2014-01-01

    Accurate equating results are essential when comparing examinee scores across exam forms. Previous research indicates that equating results may not be accurate when group differences are large. This study compared the equating results of frequency estimation, chained equipercentile, item response theory (IRT) true-score, and IRT observed-score…

  18. Foster Youth Evaluate the Performance of Group Home Services in California

    Science.gov (United States)

    Green, Rex S.; Ellis, Peter T.

    2008-01-01

    In 2003 foster youth employed by a foster youth advocacy organization suggested that an evaluation of group home services to foster youth be conducted in Alameda County, California. This report presents the development and conduct of this evaluation study; how funding was obtained; and how foster youth were hired, trained, and employed to produce…

  19. Diameter growth performance of tree functional groups in Puerto Rican secondary tropical forests

    Directory of Open Access Journals (Sweden)

    Patricia Adame

    2014-04-01

    Full Text Available Aim of study: Understanding the factors that control tree growth in successional stands is particularly important for quantifying the carbon sequestration potential and timber yield of secondary tropical forests. Understanding the factors that control tree growth in successional stands is particularly important for quantifying the carbon sequestration potential and timber yield of secondary tropical forests. Yet, the high species diversity of mixed tropical forests, including many uncommon species, hinders the development of species-specific diameter growth models.Area of study: In these analyses, we grouped 82 species from secondary forests distributed across 93 permanent plots on the island of Puerto Rico.Material and Methods: Species were classified according to regeneration strategy and adult height into six functional groups. This classification allowed us to develop a robust diameter growth model using growth data collected from 1980-1990. We used mixed linear model regression to analyze tree diameter growth as a function of individual tree characteristics, stand structure, functional group and site factors.Main results: The proportion of variance in diameter growth explained by the model was 15.1%, ranging from 7.9 to 21.7%. Diameter at breast height, stem density and functional group were the most important predictors of tree growth in Puerto Rican secondary forest. Site factors such as soil and topography failed to predict diameter growth.Keywords: Caribbean forests; growth model; tropical forest succession; Puerto Rico.

  20. The Effect of Group Composition on Individual Student Performance in an Introductory Economics Course

    Science.gov (United States)

    Moore, Robert L.

    2011-01-01

    What is the best way to allocate students to small teams in those economics courses that rely on small group work to enhance individual student learning? While experts in collaborative learning provide many suggestions, little empirical work has been done. This article begins to fill the gap. It examines whether a variety of characteristics of the…

  1. EFFECTS OF CYCLIC STATIC STRETCH ON FATIGUE RECOVERY OF TRICEPS SURAE IN FEMALE BASKETBALL PLAYERS

    Directory of Open Access Journals (Sweden)

    Mehri Ghasemia

    2013-04-01

    Full Text Available Static stretch is a safe and feasible method which usually is used before exercise to avoid muscle injury and to improve muscle performance. The purpose of this study was to determine the effects of cyclic static stretch (CSS on fatigue recovery of triceps surae (TS in female basketball players.Nine athlete volunteers between 20 and 30 years participated in this study containing two sessions. After warm-up a pressure cuff was fastened above the knee joint and its pressure was increased to 140 mmHg. The subjects were asked to perform one maximum voluntary contraction (MVC followed by a fatigue test including maximum isometric fatiguing contraction of TS. These steps were similar in both sessions. Then, a two-minute rest was included in the first session while 4 static stretches were performed to TS in the second session. After interventions, one MVC was done and the pressure cuff was released. During these steps, peak torque (PT and electromyography (EMG were recorded. The amount of lower leg pain was determined by the visual analogue scale (VAS. The value of PT increased significantly after CSS but its increase was not significant after rest. It seems that the effects of rest and CSS on the EMG parameters, PT and pain are similar.

  2. Styles and Style-Stretching: How are They Related to Successful Learning?

    Science.gov (United States)

    Griffiths, Carol; İnceçay, Görsev

    2016-06-01

    Although the learning style construct has aroused much interest over the years, questions remain regarding basic issues such as definition, the validity and/or reliability of various measurement instruments, and the relationship between learning style and successful learning. Furthermore, although maintaining stylistic flexibility is recommended by many authors, few studies have attempted to relate the style-stretching concept to successful learning. This study therefore attempted to address these questions. According to results, conducted among 106 Turkish university students, using an original instrument constructed using elements from established questionnaires, a small group of styles was significantly correlated with exam results, accounting for about a quarter of the variance (considered a large effect size in social science). In addition, higher-scoring students reported a more eclectic range of styles, suggesting more willingness to style-stretch, while lower-scoring students reported a more limited range. Pedagogical implications as well as areas for ongoing research are suggested.

  3. Performance Values for Non-Destructive Assay (NDA) Technique Applied to Wastes: Evaluation by the ESARDA NDA Working Group

    International Nuclear Information System (INIS)

    Rackham, Jamie; Weber, Anne-Laure; Chard, Patrick

    2012-01-01

    The first evaluation of NDA performance values was undertaken by the ESARDA Working Group for Standards and Non Destructive Assay Techniques and was published in 1993. Almost ten years later in 2002 the Working Group reviewed those values and reported on improvements in performance values and new measurement techniques that had emerged since the original assessment. The 2002 evaluation of NDA performance values did not include waste measurements (although these had been incorporated into the 1993 exercise), because although the same measurement techniques are generally applied, the performance is significantly different compared to the assay of conventional Safeguarded special nuclear material. It was therefore considered more appropriate to perform a separate evaluation of performance values for waste assay. Waste assay is becoming increasingly important within the Safeguards community, particularly since the implementation of the Additional Protocol, which calls for declaration of plutonium and HEU bearing waste in addition to information on existing declared material or facilities. Improvements in the measurement performance in recent years, in particular the accuracy, mean that special nuclear materials can now be accounted for in wastes with greater certainty. This paper presents an evaluation of performance values for the NDA techniques in common usage for the assay of waste containing special nuclear material. The main topics covered by the document are: 1- Techniques for plutonium bearing solid wastes 2- Techniques for uranium bearing solid wastes 3 - Techniques for assay of fissile material in spent fuel wastes. Originally it was intended to include performance values for measurements of uranium and plutonium in liquid wastes; however, as no performance data for liquid waste measurements was obtained it was decided to exclude liquid wastes from this report. This issue of the performance values for waste assay has been evaluated and discussed by the ESARDA

  4. Performance Values for Non-Destructive Assay (NDA) Technique Applied to Wastes: Evaluation by the ESARDA NDA Working Group

    Energy Technology Data Exchange (ETDEWEB)

    Rackham, Jamie [Babcock International Group, Sellafield, Seascale, Cumbria, (United Kingdom); Weber, Anne-Laure [Institut de Radioprotection et de Surete Nucleaire Fontenay-Aux-Roses (France); Chard, Patrick [Canberra, Forss Business and Technology park, Thurso, Caithness (United Kingdom)

    2012-12-15

    The first evaluation of NDA performance values was undertaken by the ESARDA Working Group for Standards and Non Destructive Assay Techniques and was published in 1993. Almost ten years later in 2002 the Working Group reviewed those values and reported on improvements in performance values and new measurement techniques that had emerged since the original assessment. The 2002 evaluation of NDA performance values did not include waste measurements (although these had been incorporated into the 1993 exercise), because although the same measurement techniques are generally applied, the performance is significantly different compared to the assay of conventional Safeguarded special nuclear material. It was therefore considered more appropriate to perform a separate evaluation of performance values for waste assay. Waste assay is becoming increasingly important within the Safeguards community, particularly since the implementation of the Additional Protocol, which calls for declaration of plutonium and HEU bearing waste in addition to information on existing declared material or facilities. Improvements in the measurement performance in recent years, in particular the accuracy, mean that special nuclear materials can now be accounted for in wastes with greater certainty. This paper presents an evaluation of performance values for the NDA techniques in common usage for the assay of waste containing special nuclear material. The main topics covered by the document are: 1- Techniques for plutonium bearing solid wastes 2- Techniques for uranium bearing solid wastes 3 - Techniques for assay of fissile material in spent fuel wastes. Originally it was intended to include performance values for measurements of uranium and plutonium in liquid wastes; however, as no performance data for liquid waste measurements was obtained it was decided to exclude liquid wastes from this report. This issue of the performance values for waste assay has been evaluated and discussed by the ESARDA

  5. Coping style and performance status in a group of oncological inpatients

    Directory of Open Access Journals (Sweden)

    Cecilia Chau Pérez-Aranibar

    2002-06-01

    Full Text Available The associations between coping styles, measured by COPE Test, dispositional version (Carver,Scheier and Weintraub, 1989, and Health Status inferred through a performance status, measured by Karnofsky's Index of Behavioral Performance are examined. The study focuses upon 28 oncological in patients. Positive moderate Pearson's correlations were found between these two variables in this correlational-descriptive study. These were interpreted in the following sense: the larger use of the style, the less health status among the scales suppression of competent activities, procrastination of coping, instrumental social support, focusing and releasing of emotions and behavioral disengagement. The active coping scale presented a negative correlationwith regard to Performance Status as a health measure.

  6. HOW TO IMPROVE EMPLOYEE MOTIVATION AND GROUP PERFORMANCE THROUGH LEADERSHIP – CONCEPTUAL MODEL

    Directory of Open Access Journals (Sweden)

    Tebeian Adriana

    2012-07-01

    Full Text Available We live times of intense change, due to fast technological development, when information and knowledge are certain factors of power. Organizations today must not underestimate the importance of capable employees, owners of these great factors like information and knowledge. The key to success, as many organizations have shown, is, of course a mix of attributes, but one of much importance stands in the quality of employees and their performance. How to motivate and keep such employees is a real challenge in the actual business world. Employee fluctuation is a big risk, because it brings many losses: loss of expertise, of know-how, of time, it breaks relationships and teams. One solution to this problem is creating a good and attractive environment, so that employees are motivated enough to bring up the best in them and rise their performance to a high level. The main objective of this study is to present a new approach in motivating employees and raising their performance. In this approach, the leader is the main pawn, the generator and sustainer of a healthy environment. By reviewing the literature and the most recent works in this domain, two styles of leadership come into focus: transformational and servant leadership. Both are relatively new concepts, with common but also different attributes, and both having the same final goal: performance, but through a different approach. Based on a vast literature research, the conceptual model was built, considering the main attributes of the two leadership styles, their impact on motivational factors, their influence on job satisfaction and ultimately on team performance. The intermediary results of the research sustain the conceptual framework and main hypothesis of the study. One important contribution of this research is introducing elements of servant leadership together with transformational leadership in the empirical research and also creating an overall conceptual framework which can be applied

  7. Performance of the Radioprotection Engineering Group in the new structure of IPEN-CNEN/SP

    International Nuclear Information System (INIS)

    Sahyun, A.; Sordi, G.M.A.A.

    1992-01-01

    A comparison between the old and now CNEN (Brazilian Nuclear Energy Commission) organizational structure was performed. The new structure lead to a new IPEN (Nuclear and Energetics Research Institute) organization and also to gave use to a Radioprotection Engineering Area, The principal modification raised a second block already in accomplishment. The main aim of the Radioprotection Engineering Area is to turn personnel team interested, concerned, dexterous, dynamic and competitive on their activities besides to provide it of a continuously improvement and updating about technical activities in radiation protection. From these results an evaluation of possible drawbacks and ways to overcome them will be performed. (author)

  8. Effect of Bulky and Hydroxyl Groups on Gas Separation Performance of Polyimide Membranes.

    Science.gov (United States)

    Lee, Bo Mi; Kim, Deuk Ju; Nam, Sang Yong

    2015-03-01

    A series of polyimides were synthesized by a polycondensation reaction using various aromatic dianhydrides and diamines containing bulky cardo and hydroxyl groups. The imidization and chemical structure of the polyimides were confirmed by NMR and FT-IR. The thermal and gas properties of the polyimides were measured by time-lag, XRD, TGA, and DSC studies. The polyimides showed excellent solubility in common organic solvents and high thermal stability. The CO2 selectivity of HPI membrane was higher than traditional polyimides. In particular, the incorporation of hydroxyl groups improved the CO2 permeability of the polyimide due to increased carbon dioxide solubility. The HPI was thermally converted to polybenzoxazole (PBO) at 450 °C.

  9. Analysis of Employee Engagement to Improve the Performance of Retail Risk Group PT Bank Mandiri

    Science.gov (United States)

    Wiseto, Artody; Hubeis, Aida Vitayala; Sukandar, Dadang

    2016-01-01

    Nowadays, every company requires their employees have a bound sense to their company. It's called engagement. Also have that expectation, PT Bank Mandiri (Persero) Tbk, Bank with the largest assets in Indonesia. PT Bank Mandiri (Persero) Tbk expect which employee engagement can improve the performance such as financial, service, and production…

  10. Performance Variables and Professional Experience in Simulated Laparoscopy: A Two-Group Learning Curve Study

    NARCIS (Netherlands)

    Luursema, J.M.; Rovers, Maroeska M.; Groenier, Marleen; van Goor, Harry

    2014-01-01

    Objective Virtual reality simulators are increasingly used in laparoscopy training. Such simulators allow objective assessment of performance. However, both low-level variables and overall scores generated by the simulator can be hard to interpret. We present a method to generate intermediate

  11. Performance variables and professional experience in simulated laparoscopy: a two-group learning curve study

    NARCIS (Netherlands)

    Luursema, J.M.; Rovers, M.M.; Groenier, M.; Goor, H. van

    2014-01-01

    OBJECTIVE: Virtual reality simulators are increasingly used in laparoscopy training. Such simulators allow objective assessment of performance. However, both low-level variables and overall scores generated by the simulator can be hard to interpret. We present a method to generate intermediate

  12. COMPUTERS: Teraflops for Europe; EEC Working Group on High Performance Computing

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1991-03-15

    In little more than a decade, simulation on high performance computers has become an essential tool for theoretical physics, capable of solving a vast range of crucial problems inaccessible to conventional analytic mathematics. In many ways, computer simulation has become the calculus for interacting many-body systems, a key to the study of transitions from isolated to collective behaviour.

  13. Variations in Financial Performance among Peer Groups of Critical Access Hospitals

    Science.gov (United States)

    Pink, George H.; Holmes, George M.; Thompson, Roger E.; Slifkin, Rebecca T.

    2007-01-01

    Context: Among the large number of hospitals with critical access hospital (CAH) designation, there is substantial variation in facility revenue as well as the number and types of services provided. If these variations have material effects on financial indicators, then performance comparisons among all CAHs are problematic. Purpose: To…

  14. Benchmarking road safety performance by grouping local territories : a study in The Netherlands.

    NARCIS (Netherlands)

    Aarts, L.T. & Houwing, S.

    2015-01-01

    The method of benchmarking provides an opportunity to learn from better performing territories to improve the effectiveness and efficiency of activities in a particular field of interest. Such a field of interest could be road safety. Road safety benchmarking can include several indicators, ranging

  15. Strengthening Collective Action to Improve Marketing Performance: Evidence from Farmer Groups in Central Africa

    Science.gov (United States)

    Ochieng, Justus; Knerr, Beatrice; Owuor, George; Ouma, Emily

    2018-01-01

    Purpose: Several development organisations have implemented programs to enhance smallholder farmers' crop productivity and market access through collective action with mixed results. Therefore, this study examines the drivers of success of collective action initiatives as a pathway to improving farmers marketing performance using data from Rwanda…

  16. Foreign and domestic ownership, business groups, and firm performance: evidence from a large emerging market

    NARCIS (Netherlands)

    Douma, Sytse; George, Rejie; Kabir, Mohammed Rezaul

    2006-01-01

    We adopt a multi-theoretic approach to investigate a previously unexplored phenomenon in extant literature, namely the differential impact of foreign institutional and foreign corporate shareholders on the performance of emerging market firms. We show that the previously documented positive effect

  17. Adaptive aspirations : Performance consequences of risk preferences at extremes and alternative reference groups

    NARCIS (Netherlands)

    Hu, S.; Blettner, D.P.; Bettis, R.

    2011-01-01

    Goals or aspirations and their relationships to risk taking and performance are important issues in both psychology and strategic management. The concept of adaptive aspirations, as discussed in Cyert and March's Behavioral Theory of the Firm, has long been a topic of interest in both fields.

  18. COMPUTERS: Teraflops for Europe; EEC Working Group on High Performance Computing

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    In little more than a decade, simulation on high performance computers has become an essential tool for theoretical physics, capable of solving a vast range of crucial problems inaccessible to conventional analytic mathematics. In many ways, computer simulation has become the calculus for interacting many-body systems, a key to the study of transitions from isolated to collective behaviour

  19. Effects of Stretching by P.N.F and Harmonic Techniques on Hamstring Flexibility

    Directory of Open Access Journals (Sweden)

    Hassan Shakeri

    2006-01-01

    Full Text Available Objective: Improving of muscle flexibility is an important issue in physiotherapy and sport sciences. There are many methods for increasing muscle length and decreasing muscle stiffness. In research findings, PNF method has been found to be better than static and ballistic methods. There is another method named Harmonic technique (introduced by E. Lederman 1997 that has been claimed to be more effective, but there is not enough documentation about this claim. Aim of this study was to compare effects of stretching by PNF and harmonic techniques on hamstring flexibility. Materials & Methods: This research is a RCT study in that 45 colledge students aged 18-35 years were arranged in three groups (Harmonic, P.N.F, and control. Subjects haven’t had any painful pathology in low-back and lower extremities for last six months. Subjects had limited hamstring length (20 degrees deficiency in Active-Knee-Extension test and hadn’t professional sport activities. Dependent variablies were muscle stiffness and hamstring length which popliteal angle in AKE test was its indirect index. In pilot study, reliability of measurement of these variables were approved. Then hamstring muscle of subjects in harmonic and PNF groups were stretched by harmonic and PNF methods for six weeks, 5 minute per day and 3d/wks, whereas control group hadn’t any exercise. Results: Findings of this study showed that in both used techniques, changes of hamstring length were significant (P=0.000, but in control group there wasn’t significant change. There wasn’t significant differences between changes of hamstring length in PNF and Harmonic groups. Only in harmonic group, muscle stiffness had significant changes (P<0.03. Conclusion: According to findings of this research, both harmonic and PNF methods equally increased length of hamstring, and harmonic technique can be used as an alternative stretching method for other techniques. Maybe harmonic technique is better than PNF

  20. Materials management: stretching the "household" budget.

    Science.gov (United States)

    Carpe, R H; Carroll, P E

    1987-11-01

    As CFOs assume responsibility for the materials management function because of the potential to maximize cash flow, achieve economies of scale, decrease costs, and streamline operations, they look for guidelines to evaluate performance. Conducting a systems operations audit can aid in assessing that performance. CFOs can determine whether materials management processes are working "smarter, nor harder."

  1. Influences of the Capital Structure and the Cost of Capital on Financial Performance. Case Study on ENGIE Group

    OpenAIRE

    Elena Valentina IVASCU; Nicoleta BARBUTA-MISU

    2017-01-01

    The main objectives of the company's financial management are to ensure financial performances and to choose the capital structure that corresponds to the lowest total cost of capital. The purpose of this paper is to analyse the relationship between the capital structure and cost, and the financial performance of Engie Transnational Group, one of the most important global electricity producers. The data used were extracted from the Amadeus and Bloomberg databases for the period 2010-2015. Fin...

  2. Determination Performance Of Gamma Spectrometry Co-Axial HPGE Detector In Radiochemistry And Environment Group, Nuclear Malaysia

    International Nuclear Information System (INIS)

    Mei-Woo, Y.

    2014-01-01

    Gamma Spectrometry System is used to measure qualitatively and quantitatively a gamma emitting radionuclide. The accuracy of the measurement very much depends on the performance specifications of the HPGe detectors. From this study it found that all the seven co-axial HPGe detectors in Radiochemistry and Environment Group, Nuclear Malaysia are in good working conditions base on the verification of performance specifications namely Resolution, Peak Shape, Peak-to-Compton ratio and Relative Efficiency against the warranted value from the manufacturers. (author)

  3. Performance of microscopy and ELISA for diagnosing Giardia duodenalis infection in different pediatric groups.

    Science.gov (United States)

    Silva, Renata K N R; Pacheco, Flávia T F; Martins, Adson S; Menezes, Joelma F; Costa-Ribeiro, Hugo; Ribeiro, Tereza C M; Mattos, Ângela P; Oliveira, Ricardo R; Soares, Neci M; Teixeira, Márcia C A

    2016-12-01

    Techniques for Giardia diagnosis based on microscopy are usually applied as routine laboratory testing; however, they typically exhibit low sensitivity. This study aimed to evaluate Giardia duodenalis and other intestinal parasitic infections in different pediatric groups, with an emphasis on the comparison of Giardia diagnostic techniques. Feces from 824 children from different groups (diarrheic, malnourished, with cancer and from day care) were examined by microscopy and ELISA for Giardia, Cryptosporidium sp. and Entamoeba histolytica coproantigen detection. Giardia-positive samples from day-care children, identified by either microscopy or ELISA, were further tested by PCR targeting of the β-giardin and Gdh genes. Statistically significant differences (Psp. in diarrheic and malnourished groups; infections by Entamoeba histolytica were found only in children with diarrhea. Considering positivity for Giardia by at least one method, ELISA was found to be more sensitive than microscopy (97% versus 55%). To examine discrepancies among the diagnostic methods, 71 Giardia-positive stool samples from day-care children were tested by PCR; of these, DNA was amplified from 51 samples (77.4%). Concordance of positivity between microscopy and ELISA was found for 48 samples, with 43 confirmed by PCR. Parasite DNA was amplified from eleven of the 20 Giardia samples (55%) identified only by ELISA. This study shows the higher sensitivity of ELISA over microscopy for Giardia diagnosis when a single sample is analyzed and emphasizes the need for methods based on coproantigen detection to identify this parasite in diarrheic fecal samples. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. Performance values for non destructive assay (NDA) techniques applied to safeguards: the 2002 evaluation by the ESARDA NDA Working Group

    International Nuclear Information System (INIS)

    Guardini, S.

    2003-01-01

    The first evaluation of NDA performance values undertaken by the ESARDA Working Group for Standards and Non Destructive Assay Techniques (WGNDA) was published in 1993. Almost 10 years later the Working Group decided to review those values, to report about improvements and to issue new performance values for techniques which were not applied in the early nineties, or were at that time only emerging. Non-Destructive Assay techniques have become more and more important in recent years, and they are used to a large extent in nuclear material accountancy and control both by operators and control authorities. As a consequence, the performance evaluation for NDA techniques is of particular relevance to safeguards authorities in optimising Safeguards operations and reducing costs. Performance values are important also for NMAC regulators, to define detection levels, limits for anomalies, goal quantities and to negotiate basic audit rules. This paper presents the latest evaluation of ESARDA Performance Values (EPVs) for the most common NDA techniques currently used for the assay of nuclear materials for Safeguards purposes. The main topics covered by the document are: techniques for plutonium bearing materials: PuO 2 and MOX; techniques for U-bearing materials; techniques for U and Pu in liquid form; techniques for spent fuel assay. This issue of the performance values is the result of specific international round robin exercises, field measurements and ad hoc experiments, evaluated and discussed in the ESARDA NDA Working Group. (author)

  5. Performance of the block-Krylov energy group solvers in Jaguar

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A. M.; Kennedy, R. A. [Knolls Atomic Power Laboratory, Bechtel Marine Propulsion Corporation, P.O. Box 1072, Schenectady, NY 12301-1072 (United States)

    2012-07-01

    A new method of coupling the inner and outer iterations for deterministic transport problems is proposed. This method is termed the Multigroup Energy Blocking Method (MEBM) and has been implemented in the deterministic transport solver Jaguar, which is currently under development at KAPL. The method is derived for both fixed-source and eigenvalue problems. The method is then applied to a PWR pin cell model, both in fixed-source mode and eigenvalue mode. The results show that the MEBM improves the convergence of both types of problems when applied to the thermal (up-scattering) groups. (authors)

  6. Cyclic Stretch Alters Vascular Reactivity of Mouse Aortic Segments

    Directory of Open Access Journals (Sweden)

    Arthur Leloup

    2017-10-01

    Full Text Available Large, elastic arteries buffer the pressure wave originating in the left ventricle and are constantly exposed to higher amplitudes of cyclic stretch (10% than muscular arteries (2%. As a crucial factor for endothelial and smooth muscle cell function, cyclic stretch has, however, never been studied in ex vivo aortic segments of mice. To investigate the effects of cyclic stretch on vaso-reactivity of mouse aortic segments, we used the Rodent Oscillatory Tension Set-up to study Arterial Compliance (ROTSAC. The aortic segments were clamped at frequencies of 6–600 bpm between two variable preloads, thereby mimicking dilation as upon left ventricular systole and recoiling as during diastole. The preloads corresponding to different transmural pressures were chosen to correspond to a low, normal or high amplitude of cyclic stretch. At different time intervals, cyclic stretch was interrupted, the segments were afterloaded and isometric contractions by α1-adrenergic stimulation with 2 μM phenylephrine in the absence and presence of 300 μM L-NAME (eNOS inhibitor and/or 35 μM diltiazem (blocker of voltage-gated Ca2+ channels were measured. As compared with static or cyclic stretch at low amplitude (<10 mN or low frequency (0.1 Hz, cyclic stretch at physiological amplitude (>10 mN and frequency (1–10 Hz caused better ex vivo conservation of basal NO release with time after mounting. The relaxation of PE-precontracted segments by addition of ACh to stimulate NO release was unaffected by cyclic stretch. In the absence of basal NO release (hence, presence of L-NAME, physiological in comparison with aberrant cyclic stretch decreased the baseline tension, attenuated the phasic contraction by phenylephrine in the absence of extracellular Ca2+ and shifted the smaller tonic contraction more from a voltage-gated Ca2+ channel-mediated to a non-selective cation channel-mediated. Data highlight the need of sufficient mechanical activation of endothelial and

  7. Automatic focusing in digital holography and its application to stretched holograms.

    Science.gov (United States)

    Memmolo, P; Distante, C; Paturzo, M; Finizio, A; Ferraro, P; Javidi, B

    2011-05-15

    The searching and recovering of the correct reconstruction distance in digital holography (DH) can be a cumbersome and subjective procedure. Here we report on an algorithm for automatically estimating the in-focus image and recovering the correct reconstruction distance for speckle holograms. We have tested the approach in determining the reconstruction distances of stretched digital holograms. Stretching a hologram with a variable elongation parameter makes it possible to change the in-focus distance of the reconstructed image. In this way, the proposed algorithm can be verified at different distances by dispensing the recording of different holograms. Experimental results are shown with the aim of demonstrating the usefulness of the proposed method, and a comparative analysis has been performed with respect to other existing algorithms developed for DH. © 2011 Optical Society of America

  8. Artificial intelligence in label-free microscopy biological cell classification by time stretch

    CERN Document Server

    Mahjoubfar, Ata; Jalali, Bahram

    2017-01-01

    This book introduces time-stretch quantitative phase imaging (TS-QPI), a high-throughput label-free imaging flow cytometer developed for big data acquisition and analysis in phenotypic screening. TS-QPI is able to capture quantitative optical phase and intensity images simultaneously, enabling high-content cell analysis, cancer diagnostics, personalized genomics, and drug development. The authors also demonstrate a complete machine learning pipeline that performs optical phase measurement, image processing, feature extraction, and classification, enabling high-throughput quantitative imaging that achieves record high accuracy in label -free cellular phenotypic screening and opens up a new path to data-driven diagnosis. • Demonstrates how machine learning is used in high-speed microscopy imaging to facilitate medical diagnosis; • Provides a systematic and comprehensive illustration of time stretch technology; • Enables multidisciplinary application, including industrial, biomedical, and artificial intell...

  9. Stretch activates myosin light chain kinase in arterial smooth muscle

    International Nuclear Information System (INIS)

    Barany, K.; Rokolya, A.; Barany, M.

    1990-01-01

    Stretching of porcine carotid arterial muscle increased the phosphorylation of the 20 kDa myosin light chain from 0.23 to 0.68 mol [32P]phosphate/mol light chain, whereas stretching of phorbol dibutyrate treated muscle increased the phosphorylation from 0.30 to 0.91 mol/mol. Two-dimensional gel electrophoresis followed by two-dimensional tryptic phosphopeptide mapping was used to identify the enzyme involved in the stretch-induced phosphorylation. Quantitation of the [32P]phosphate content of the peptides revealed considerable light chain phosphorylation by protein kinase C only in the phorbol dibutyrate treated arterial muscle, whereas most of the light chain phosphorylation was attributable to myosin light chain kinase. Upon stretch of either the untreated or treated muscle, the total increment in [32P]phosphate incorporation into the light chain could be accounted for by peptides characteristic for myosin light chain kinase catalyzed phosphorylation, demonstrating that the stretch-induced phosphorylation is caused by this enzyme exclusively

  10. SURGICAL TREATMENT FOR FEMOROACETABULAR IMPINGEMENT IN A GROUP THAT PERFORMS SQUATS.

    Science.gov (United States)

    Polesello, Giancarlo Cavalli; Cinagawa, Eduardo Hitoshi Tsuge; Cruz, Paulo Daniel Sousa Santa; de Queiroz, Marcelo Cavalheiro; Borges, Cristian Jandrey; Junior, Walter Ricioli; Daniachi, Daniel; Guimarães, Rodrigo Pereira; Honda, Emerson Kiyoshi; Ono, Nelson Keiske

    2012-01-01

    Describe the results from arthroscopic surgical treatment on a group of patients who developed symptoms after repetitive physical activity of moving their hips in a position of hyperflexion, as in leg presses and squats. The study group comprised 47 individuals (48 hips) who developed the onset of painful symptoms associated with hip hyperflexion exercises (leg presses or squats) and underwent arthroscopic treatment. The patients were evaluated radiographically and clinically according to the "Harris Hip Score", as modified by Byrd (MHHS), pre and postoperatively, and were asked about their return to sports activities and the surgical findings. The mean preoperative and postoperative MHHS, respectively, were 60 points (SD 11.0, range 38.5 to 92.4) and 95.9 points (SD 7.7, range 63.8 to 100), with an increase of 35.9 points (P < 0.001). Regarding physical activity, 30 individuals (71.5%) resumed sports activities after surgery, and 25 of them (83.4%) at the previous level. Six patients (12.8%) did not resume activities because of persistent pain. During arthroscopy, 48 hips (100%) presented lesions of the acetabular labrum, and 41 hips (85.4%) had acetabular chondral lesions. The patients with painful symptoms after hip hyperflexion exercises associated with femoroacetabular impingement presented improvements after arthroscopic treatment.

  11. MULTIPROFESSIONAL AND INTERDISCIPLINARY ACTIVITES PERFORMED ON A GROUP WITH SPECIAL NEEDS: REPORTS OF AN EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Geny Aparecida Cantos

    2010-12-01

    Full Text Available The cardiovascular prevention is based on efforts to prevent or avoid new cardiovascular events. In 1997, a multidisciplinary and interdisciplinary group planned activities focused on awareness of patients for stress management and health promotion. The objective was to provide individuals with special needs, which mostly belonged to the university community, access to alternative practices different from those already available in the medical model and medical technology. It was offered the participants a set of alternative treatments that provided the integration and harmonization of the body as a whole, to integrate conventional medicine with other care models of health promotion. These alternative treatments were: Biodanza ®; and tree water activites (watsu, Halliwick and Biodanza ®, psychological attetion and nutritional education with community lunches and visits to the supermarket, and recreational experiences of the heart, in addition to cardiac monitoring and monthly lectures. The results showed the importance of patients become aware of how they were acting, and from this perception they might believe, plan and be responsible for positive changes in their daily attitudes, contributing to a better quality of life and psychological well-being. These different ways of handling this in different therapeutic groups strengthened the human values associated with the physical and emotional recovery of these patients, better integrating them with the world, with others and with himselves.

  12. Stretching of a polymer chain anchored to a surface: the massive field theory approach

    International Nuclear Information System (INIS)

    Usatenko, Zoryana

    2014-01-01

    Taking into account the well-known correspondence between the field theoretical φ 4 O(n)-vector model in the limit n → 0 and the behaviour of long-flexible polymer chains, the investigation of stretching of an ideal and a real polymer chain with excluded volume interactions in a good solvent anchored to repulsive and inert surfaces is performed. The calculations of the average stretching force which arises when the free end of a polymer chain moves away from a repulsive or inert surface are performed up to one-loop order of the massive field theory approach in fixed space dimensions d = 3. The analysis of the obtained results indicates that the average stretching force for a real polymer chain anchored to a repulsive surface demonstrates different behaviour for the cases z-tilde ≪1 and z-tilde ≫1, where z-tilde =z ′ /R z . Besides, the results obtained in the framework of the massive field theory approach are in good agreement with previous theoretical results for an ideal polymer chain and results of a density functional theory approach for the region of small applied forces when deformation of a polymer chain in the direction of the applied force is not bigger than the linear extension of a polymer chain in this direction. The better agreement between these two methods is observed in the case where the number of monomers increases and the polymer chain becomes longer. (paper)

  13. Active stretching for lower extremity muscle tightness in pediatric patients with lumbar spondylolysis.

    Science.gov (United States)

    Sato, Masahiro; Mase, Yasuyoshi; Sairyo, Koichi

    2017-01-01

    It was reported that hamstring muscle tightness may increase mechanical loading on the lumbar spine. Therefore, we attempt to decrease tightness in the leg muscles in pediatric patients. Forty-six pediatric patients with spondylolysis underwent rehabilitation. We applied active stretching to the hamstrings, quadriceps, and triceps surae. Tightness in each muscle was graded as good, fair, or poor. We educated each patient on how to perform active stretching at home. They were re-evaluated for muscle tightness 2 months later. Tightness at baseline and after 2 months was as follows: for the hamstrings, good in 3 patients, fair in 9, and poor in 34 and significant improved after 2 months (p<0.05), with improvement by least 1 grade seen in 86% of patients with fair or poor at baseline; for the quadriceps, 7, 3, and 30 patients had good, fair and poor, with significant improvements in 72% (p<0.05). For the triceps surae, 6, 3 and 10 patients had good, fair and poor, which improved significantly (p<0.05). Home-based active stretching was effective for relieving muscle tightness in the leg in a pediatric population. Adolescent athletes should perform such exercise to maintain flexibility and prevent lumbar disorders. J. Med. Invest. 64: 136-139, February, 2017.

  14. Attributions of the "causes" of group performance as an alternative explanation of the relationship between organizational citizenship behavior and organizational performance.

    Science.gov (United States)

    Bachrach, D G; Bendoly, E; Podsakoff, P M

    2001-12-01

    The purpose of this study was to examine the possibility that feedback regarding team performance may influence team members' reports of organizational citizenship behaviors. Ninety-five teams of business students (N = 412) participated in a labor-scheduling simulation over a local area network. Teams were provided with false negative, false positive, or neutral feedback regarding their performance. Results support the hypothesis that the perception of 2 forms of organizational citizenship behavior (helping behavior and civic virtue) in work groups may, in part. be a function of the nature of the performance feedback that group members receive. However, negative feedback appears to play a more critical role than positive feedback in this attributional process. Possible reasons for these findings, as well as their implications, are discussed.

  15. Restorative Yoga and Metabolic Risk Factors: The Practicing Restorative Yoga vs. Stretching for the Metabolic Syndrome (PRYSMS) randomized trial

    Science.gov (United States)

    Kanaya, Alka M.; Araneta, Maria Rosario G.; Pawlowsky, Sarah B.; Barrett-Connor, Elizabeth; Grady, Deborah; Vittinghoff, Eric; Schembri, Michael; Chang, Ann; Carrion-Petersen, Mary Lou; Coggins, Traci; Tanori, Daniah; Armas, Jean M.; Cole, Roger J.

    2014-01-01

    Aims Intensive lifestyle change prevents type 2 diabetes but is difficult to sustain. Preliminary evidence suggests that yoga may improve metabolic factors. We tested a restorative yoga intervention vs. active stretching for metabolic outcomes. Methods In 2009–2012, we conducted a 48-week randomized trial comparing restorative yoga vs. stretching among underactive adults with the metabolic syndrome at the Universities of California, San Francisco and San Diego. We provided lifestyle counseling and a tapering series of 90-minute group classes in the 24-week intervention period and 24-week maintenance period. Fasting and 2-hour glucose, HbA1c, triglycerides, HDL-cholesterol, insulin, systolic blood pressure, visceral fat, and quality of life were assessed at baseline, 6- and 12-months. Results 180 participants were randomized and 135 (75%) completed the trial. At 12 months, fasting glucose decreased more in the yoga group than in the stretching group (−0.35 mmol/L vs. −0.03 mmol/L; p=0.002); there were no other significant differences between groups. At 6 months favorable changes within the yoga group included reductions in fasting glucose, insulin, and HbA1c and an increase in HDL-cholesterol that were not sustained at 1 year except changes in fasting glucose. The stretching group had a significant reduction in triglycerides at 6 months which was not sustained at 1 year but had improved quality of life at both time-points. Conclusions Restorative yoga was marginally better than stretching for improving fasting glucose but not other metabolic factors. PMID:24418351

  16. An Earth-Based Equivalent Low Stretch Apparatus to Assess Material Flammability for Microgravity & Extraterrestrial Fire-Safety Applications

    Science.gov (United States)

    Olson, S. L.; Beeson, H.; Haas, J.

    2001-01-01

    One of the performance goals for NASA's enterprise of Human Exploration and Development of Space (HEDS) is to develop methods, data bases, and validating tests for material flammability characterization, hazard reduction, and fire detection/suppression strategies for spacecraft and extraterrestrial habitats. This work addresses these needs by applying the fundamental knowledge gained from low stretch experiments to the development of a normal gravity low stretch material flammability test method. The concept of the apparatus being developed uses the low stretch geometry to simulate the conditions of the extraterrestrial environment through proper scaling of the sample dimensions to reduce the buoyant stretch in normal gravity. The apparatus uses controlled forced-air flow to augment the low stretch to levels which simulate Lunar or Martian gravity levels. In addition, the effect of imposed radiant heat flux on material flammability can be studied with the cone heater. After breadboard testing, the apparatus will be integrated into NASA's White Sands Test Facility's Atmosphere-Controlled Cone Calorimeter for evaluation as a new materials screening test method.

  17. A large-scale examination of the effectiveness of anonymous marking in reducing group performance differences in higher education assessment.

    Directory of Open Access Journals (Sweden)

    Daniel P Hinton

    Full Text Available The present research aims to more fully explore the issues of performance differences in higher education assessment, particularly in the context of a common measure taken to address them. The rationale for the study is that, while performance differences in written examinations are relatively well researched, few studies have examined the efficacy of anonymous marking in reducing these performance differences, particularly in modern student populations. By examining a large archive (N = 30674 of assessment data spanning a twelve-year period, the relationship between assessment marks and factors such as ethnic group, gender and socio-environmental background was investigated. In particular, analysis focused on the impact that the implementation of anonymous marking for assessment of written examinations and coursework has had on the magnitude of mean score differences between demographic groups of students. While group differences were found to be pervasive in higher education assessment, these differences were observed to be relatively small in practical terms. Further, it appears that the introduction of anonymous marking has had a negligible effect in reducing them. The implications of these results are discussed, focusing on two issues, firstly a defence of examinations as a fair and legitimate form of assessment in Higher Education, and, secondly, a call for the re-examination of the efficacy of anonymous marking in reducing group performance differences.

  18. A large-scale examination of the effectiveness of anonymous marking in reducing group performance differences in higher education assessment.

    Science.gov (United States)

    Hinton, Daniel P; Higson, Helen

    2017-01-01

    The present research aims to more fully explore the issues of performance differences in higher education assessment, particularly in the context of a common measure taken to address them. The rationale for the study is that, while performance differences in written examinations are relatively well researched, few studies have examined the efficacy of anonymous marking in reducing these performance differences, particularly in modern student populations. By examining a large archive (N = 30674) of assessment data spanning a twelve-year period, the relationship between assessment marks and factors such as ethnic group, gender and socio-environmental background was investigated. In particular, analysis focused on the impact that the implementation of anonymous marking for assessment of written examinations and coursework has had on the magnitude of mean score differences between demographic groups of students. While group differences were found to be pervasive in higher education assessment, these differences were observed to be relatively small in practical terms. Further, it appears that the introduction of anonymous marking has had a negligible effect in reducing them. The implications of these results are discussed, focusing on two issues, firstly a defence of examinations as a fair and legitimate form of assessment in Higher Education, and, secondly, a call for the re-examination of the efficacy of anonymous marking in reducing group performance differences.

  19. Among Friends: The Role of Academic-Preparedness Diversity in Individual Performance within a Small-Group STEM Learning Environment

    Science.gov (United States)

    Micari, Marina; Van Winkle, Zachary; Pazos, Pilar

    2016-01-01

    In this study, we investigate the relationship between academic-preparedness diversity within small learning groups and individual academic performance in science, technology, engineering, and mathematics (STEM) university courses. We further examine whether academic-preparedness diversity impacts academically more- and less-prepared students…

  20. A Learning Style-Based Grouping Collaborative Learning Approach to Improve EFL Students' Performance in English Courses

    Science.gov (United States)

    Kuo, Yu-Chen; Chu, Hui-Chun; Huang, Chi-Hao

    2015-01-01

    Learning English is an important and challenging task for English as Foreign Language (EFL) students. Educators had indicated that, without proper learning support, most EFL students might feel frustrated while learning English, which could significantly affect their learning performance. In the past research, learning usually utilized grouping,…

  1. Effects of Collective Efficacy, Teamwork Attitudes, and Experience on Group Project Performance: Comparisons between 2 Food Science Courses

    Science.gov (United States)

    McLeod, Poppy Lauretta; Orta-Ramirez, Alicia

    2018-01-01

    The relationship between past teamwork and task-related experiences, attitude toward teamwork, collective efficacy, and task performance among undergraduates (N = 298) assigned to group projects (N = 48) in 2 different Food Science courses was examined. The results of survey data collected at the beginning and end of the projects showed that past…

  2. Task dynamics in self-organising task groups : expertise, motivational, and performance differences of specialists and generalists

    NARCIS (Netherlands)

    Zoethout, Kees; Jager, Wander; Molleman, Eric

    Multi-agent simulation is applied to explore how different types of task variety cause workgroups to change their task allocation accordingly. We studied two groups, generalists and specialists. We hypothesised that the performance of the specialists would decrease when task variety increases. The

  3. Torsion angle dependence of the rectifying performance in molecular device with asymmetrical anchoring groups

    International Nuclear Information System (INIS)

    Wang, L.H.; Guo, Y.; Tian, C.F.; Song, X.P.; Ding, B.J.

    2010-01-01

    Using first-principles density functional theory and nonequilibrium Green's function formalism, we investigate the effect of torsion angle on the rectifying characteristics of 4'-thiolate-biphenyl-4-dithiocarboxylate sandwiched between two Au(111) electrodes. The results show that the torsion angle has an evident influence on rectifying performance of such devices. By increasing the dihedral angle between two phenyl rings, namely changing the magnitude of the intermolecular coupling effect, a different rectifying behavior can be observed in these systems. Our findings highlight that the rectifying characteristics are intimately related to dihedral angles and can provide fundamental guidelines for the design of functional molecular devices.

  4. Performance Improvement Strategic Home Based Manufacturer Tahu And Tempe Groups Based In The District Of Jember

    Directory of Open Access Journals (Sweden)

    Istatuk Budi Yuswanto

    2017-04-01

    Full Text Available Tahu dan tempe is a product of the soybean meal that has been known since long in Indonesia. Tahu is a Chinese food products in contrast to tempe an authentic Indonesian food . As tempe tahu also favored by the people of Indonesia because it has a taste that delicious nutritious and affordable price.Industries that produce tahu dan tempe are generally small-scale home-based businesses with the number of workers a little less than 2-6 people and investments that are not too large. The use of technology in small business home-based producer of tahu dan tempe quite simple and easy to learn so it can be run by anyone. The success of small business home-based manufacturers to survive and evolve toward more advanced by knowing their strengths weaknesses opportunities that can be taken by small business home-based and threat or better known as the SWOT Strength Weakness Opportunity Threath that can be retrieved strategies that affect the success and development of small business home-based manufacturer of tahu dan tempe.Constraints faced by small businesses and home-based manufacturers know that the soybean Tepe that include budget constraints limited access to banking limited human resources marketing only the scope of Jember and lack of good management. No group or cooperative does not have a good recording making it difficult to make financial reports manufacturing planning and operational supervision and finances into this industry employers group lemah.Pembentukan help solve problems and maximize its potential.

  5. Students’ Satisfaction with the Group Work Method and its Performance Evaluation: A survey in an Italian University

    Directory of Open Access Journals (Sweden)

    Massimo Zedda

    2017-07-01

    Full Text Available Group Work Learning Method is a cooperative learning technique that has positive effects in learning: students’ active participation can increase both cognitive and social skills. Our work involved three cohorts of students of different years attending the same course at the University of Torino, Department of Psychology. The contents of the course were the same in all years, students were asked to form self-selected groups to find creative solutions to two cases regarding violent behavior in workplace. Satisfaction concerning this activity and the method to evaluate the performance of the activity were investigated. Findings confirm overall students’ satisfaction related to group work learning method. This satisfaction improves the scores in course and teacher skills satisfaction. About the evaluation, findings shown that students agreed teacher’s and peers’ evaluation of the performance.

  6. Influences of the Capital Structure and the Cost of Capital on Financial Performance. Case Study on ENGIE Group

    Directory of Open Access Journals (Sweden)

    Elena Valentina IVASCU

    2017-06-01

    Full Text Available The main objectives of the company's financial management are to ensure financial performances and to choose the capital structure that corresponds to the lowest total cost of capital. The purpose of this paper is to analyse the relationship between the capital structure and cost, and the financial performance of Engie Transnational Group, one of the most important global electricity producers. The data used were extracted from the Amadeus and Bloomberg databases for the period 2010-2015. Financial performance was analysed both by creating and proposing an aggregate index, as well as based on the Z Conan & Holder score. The company's financial structure was analysed on the basis of the total leverage ratio and for the total cost of capital, the weighted average capital cost formula was used. The results obtained at the Engie Group level show that the capital structure is predominantly indebted, and the maximum financial performance is obtained when the financial structure is minimal and the weighted average capital cost is maximum. The reversed relationship between the financial structure and the financial performance is in accordance with the financial structure theories of information asymmetry, pecking order and dynamic trade-off. The reversed relationship is confirmed in all Engie Group companies, except one company from United Kingdom.

  7. Peer-based control in self-managing teams: linking rational and normative influence with individual and group performance.

    Science.gov (United States)

    Stewart, Greg L; Courtright, Stephen H; Barrick, Murray R

    2012-03-01

    The authors use a multilevel framework to introduce peer-based control as a motivational state that emerges in self-managing teams. The authors specifically describe how peer-based rational control, which is defined as team members perceiving the distribution of economic rewards as dependent on input from teammates, extends and interacts with the more commonly studied normative control force of group cohesion to explain both individual and collective performance in teams. On the basis of data from 587 factory workers in 45 self-managing teams at 3 organizations, peer-based rational control corresponded with higher performance for both individuals and collective teams. Results further demonstrated that the rational and normative mechanism of peer-based control interacted to explain performance at both the individual and team levels. Increased peer-based rational control corresponded with higher individual and collective performance in teams with low cohesion, but the positive effects on performance were attenuated in cohesive teams.

  8. Cell volume and membrane stretch independently control K+ channel activity

    DEFF Research Database (Denmark)

    Bomholtz, Sofia Hammami; Willumsen, Niels J; Olsen, Hervør L

    2009-01-01

    A number of potassium channels including members of the KCNQ family and the Ca(2+) activated IK and SK, but not BK, are strongly and reversibly regulated by small changes in cell volume. It has been argued that this general regulation is mediated through sensitivity to changes in membrane stretch...... was not affected by membrane stretch. The results indicate that (1) activation of BK channels by local membrane stretch is not mimicked by membrane stress induced by cell swelling, and (2) activation of KCNQ1 channels by cell volume increase is not mediated by local tension in the cell membrane. We conclude....... To test this hypothesis we have studied the regulation of KCNQ1 and BK channels after expression in Xenopus oocytes. Results from cell-attached patch clamp studies (approximately 50 microm(2) macropatches) in oocytes expressing BK channels demonstrate that the macroscopic volume-insensitive BK current...

  9. Directional Cell Migration in Response to Repeated Substratum Stretching

    Science.gov (United States)

    Okimura, Chika; Iwadate, Yoshiaki

    2017-10-01

    Crawling migration plays an essential role in a variety of biological phenomena, including development, wound healing, and immune system function. Migration properties such as anterior-posterior polarity, directionality, and velocity are regulated not only by the reception of a chemoattractant but also by sensing mechanical inputs from the external environment. In this review, we describe the mechanical response of migrating cells, particularly under repeated stretching of the elastic substratum, highlighting the fact that there appear to be two independent mechanosensing systems that generate the polarity needed for migration. Cells that have no stress fibers, such as Dictyostelium cells and neutrophil-like differentiated HL-60 cells, migrate perpendicular to the stretching direction via myosin II localization. Cells that do possess stress fibers, however, such as fish keratocytes, migrate parallel to the stretching via a stress-fiber-dependent process.

  10. Probabilistic model of ligaments and tendons: Quasistatic linear stretching

    Science.gov (United States)

    Bontempi, M.

    2009-03-01

    Ligaments and tendons have a significant role in the musculoskeletal system and are frequently subjected to injury. This study presents a model of collagen fibers, based on the study of a statistical distribution of fibers when they are subjected to quasistatic linear stretching. With respect to other methodologies, this model is able to describe the behavior of the bundle using less ad hoc hypotheses and is able to describe all the quasistatic stretch-load responses of the bundle, including the yield and failure regions described in the literature. It has two other important results: the first is that it is able to correlate the mechanical behavior of the bundle with its internal structure, and it suggests a methodology to deduce the fibers population distribution directly from the tensile-test data. The second is that it can follow fibers’ structure evolution during the stretching and it is possible to study the internal adaptation of fibers in physiological and pathological conditions.

  11. Investigating the role of musical genre in human perception of music stretching resistance

    OpenAIRE

    Chen, Jun; Wang, Chaokun

    2017-01-01

    To stretch a music piece to a given length is a common demand in people's daily lives, e.g., in audio-video synchronization and animation production. However, it is not always guaranteed that the stretched music piece is acceptable for general audience since music stretching suffers from people's perceptual artefacts. Over-stretching a music piece will make it uncomfortable for human psychoacoustic hearing. The research on music stretching resistance attempts to estimate the maximum stretchab...

  12. Effect of mental imagery on performance elite athletes’ in youth and adult age groups: a randomized trial

    Directory of Open Access Journals (Sweden)

    Tohid Seif-Barghi

    2013-06-01

    Full Text Available Background: Athletes are usually skilled in physical aspects of sports; they are widely involved in physical conditioning, technical and tactical training. However they usually ignore the psychological and cognitive skills linked to their performance. Sport imagery is a well known fundamental skill that has a critical role in how a player performs and shows his/her competency during a real world game. On the other hand football as a complex team sport includes several skills linked to physical and psychological properties. We aimed to study the effect of cognitive imagery on elite football players through league competitions in two separate studies.Methods: Twenty two youth players and Twenty two adult players randomly assigned to imagery and control groups. Players in intervention group received 12 weeks training program for specific cognitive imagery and general cognitive imagery. Imagery training program focused on an important component of football performance as “successful passing”. Players in control group were assigned to a waiting list with no intervention. In order to evaluate outcome variable we assessed successful passing in real compete-tions as player performance in both pre and post test occasions.Results: Findings of study in youth participants showed that young players in interven-tion group improved the performance of passing compared to control players (OR=1.41, P0.05, CI 95%: 0.82, 1.4(.Conclusion: These results showed that cognitive imagery intervention can affect elite soccer players’ performance. This effect is more prominent in youth age football players.

  13. Belt technology stretches conveyors' coverage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-15

    With China the leading growth engine in the conveyor market, leading belt manufacturers are establishing local manufacturing plants to boost their presence. Fenner is planning to almost triple production capacity over the next three years, with a third of its investment in China. Shanxi-Phoenix Conveyor Belt Systems is a joint venture between Phoenix Conveyor Belt Systems GmbH, now part of ContiTech Ag, and its Chinese partners Lu An Mining Group Co. Ltd. and Jingcheng Anthracite Group Co. Ltd. It manufacturers steel cable belts, PVC and multi-ply belts for coal mines and power plants. Recent belt designs by FennerEurope and Metso Minerals are reported. 2 photos.

  14. Yo-Yo Intermittent Recovery Test Performance in Subelite Gaelic Football Players From Under Thirteen to Senior Age Groups.

    Science.gov (United States)

    Roe, Mark; Malone, Shane

    2016-11-01

    Roe, M and Malone, S. Yo-Yo intermittent recovery test performance in subelite Gaelic football players from under thirteen to senior age groups. J Strength Cond Res 30 (11): 3187-3193, 2016-Gaelic football is indigenous to Ireland and has similar locomotion profiles to soccer and Australian Football. Given the increasing attention on long-term player development, investigations on age-related variation in Yo-Yo intermittent recovery test level 1 (Yo-YoIR1) performance may provide useful information in talent identification, program design, and player monitoring. Therefore, the aim of this study was to evaluate Yo-YoIR1 performance across Gaelic football age groups. Male participants (n = 355) were recruited from division one, Gaelic football teams. Participants were allocated to one of the 7 groups according to respective age groups from under 13 (U13), under 14, under 15 (U15), under 16 (U16), minor, under 21 (U21), to senior age groups. Total Yo-YoIR1 distance (m) increased progressively from U13 (885 ± 347 m) to U16 (1,595 ± 380 m) equating to a rate of change of 180.2%. In comparison to U13, total distance at minor (1,206 ± 327 m) increased by 136.4%. Subsequent increases were observed in U21 (1,585 ± 445 m) and senior players (2,365 ± 489). Minimum (800-880 m) and maximum (2,240-2,280 m) total distances were comparable for U15, U16, and U21 players. Differences in total distance (m) for all age groups were statistically significant when compared to U13 players (p age groups for total distance was deemed to be large (effect size > 0.8). Similar trends were observed for maximum velocity and estimated V[Combining Dot Above]O2max. The evolution of Yo-YoIR1 performance in Gaelic football players from adolescents to adulthood highlights how maturation may influence sport-related running ability. Changes in Yo-YoIR1 performance should be closely monitored to optimize interventions for individuals transitioning across age groups.

  15. Dynamic Contractility and Efficiency Impairments in Stretch-Shortening Cycle Are Stretch-Load-Dependent After Training-Induced Muscle Damage

    NARCIS (Netherlands)

    Vaczi, Mark; Racz, Levente; Hortobagyi, Tibor; Tihanyi, Jozsef

    Vaczi, M, Racz, L, Hortobagyi, T, and Tihanyi, J. Dynamic contractility and efficiency impairments in stretch-shortening cycle are stretch-load-dependent after training-induced muscle damage. J Strength Cond Res 27(8): 2171-2179, 2013To determine the acute task and stretch-load dependency of

  16. Accountability in public health units: using a modified nominal group technique to develop a balanced scorecard for performance measurement.

    Science.gov (United States)

    Robinson, Victoria A; Hunter, Duncan; Shortt, Samuel E D

    2003-01-01

    Little attention has been paid to the need for accountability instruments applicable across all health units in the public health system. One tool, the balanced scorecard was created for industry and has been successfully adapted for use in Ontario hospitals. It consists of 4 quadrants: financial performance, outcomes, customer satisfaction and organizational development. The aim of the present study was to determine if a modified nominal group technique could be used to reach consensus among public health unit staff and public health specialists in Ontario about the components of a balanced scorecard for public health units. A modified nominal group technique consensus method was used with the public health unit staff in 6 Eastern Ontario health units (n=65) and public health specialists (n=18). 73.8% of the public health unit personnel from all six health units in the eastern Ontario region participated in the survey of potential indicators. A total of 74 indicators were identified in each of the 4 quadrants: program performance (n=44); financial performance (n=11); public perceptions (n=11); and organizational performance (n=8). The modified nominal group technique was a successful method of incorporating the views of public health personnel and specialists in the development of a balanced scorecard for public health.

  17. Towards nanopatterning by femtosecond laser ablation of pre-stretched elastomers

    Energy Technology Data Exchange (ETDEWEB)

    Surdo, Salvatore; Piazza, Simonluca; Ceseracciu, Luca; Diaspro, Alberto; Duocastella, Martí, E-mail: marti.duocastella@iit.it

    2016-06-30

    Graphical abstract: - Highlights: • We present a new approach to increase the focusing capabilities of optical systems. • Laser patterning is performed over a stretched elastomeric membrane. • After releasing stress, patterns shrink according to the applied strain. • Minimum feature size is controlled by strain, enabling sub-diffraction patterning. - Abstract: Diffraction limits the focusing capabilities of an optical system seriously constraining the use of lasers for nanopatterning. In this work, we present a novel and simple approach to reduce the minimum feature size of a laser-direct write system by ablating a pre-stretched material. In particular, by focusing and scanning a femtosecond laser beam on the surface of a uniaxially pre-stretched elastomeric membrane we are able to obtain microstructures according to a desired pattern. After removing the stress applied to the elastomer, the membrane relaxes to its original size and the ablated patterns shrink while preserving their shape. In this way, the minimum feature size that is typically determined by the optical properties of the focusing system can be now controlled by the strain applied to the elastomer during the ablation process. We demonstrate this approach by ablating lines on a stretchable polymeric membrane at different strain conditions. Experimental results are in good agreement with theoretical predictions. The proposed method opens up new interesting possibilities for the rapid prototyping of micro- and nano-structures suitable for a wide range of applications such as soft-lithography, micro-/nano-fluidics and lab-on-chip.

  18. Mechanical stretching of proteins-a theoretical survey of the Protein Data Bank

    International Nuclear Information System (INIS)

    Sulkowska, Joanna I; Cieplak, Marek

    2007-01-01

    The mechanical stretching of single proteins has been studied experimentally for about 50 proteins, yielding a variety of force patterns and peak forces. Here we perform a theoretical survey of proteins of known native structure and map out the landscape of possible dynamical behaviours under stretching at constant speed. We consider 7510 proteins comprising not more than 150 amino acids and 239 longer proteins. The model used is constructed based on the native geometry. It is solved by methods of molecular dynamics and validated by comparing the theoretical predictions to experimental results. We characterize the distribution of peak forces and investigate correlations with the system size and with the structure classification as characterized by the CATH scheme. Despite the presence of such correlations, proteins with the same CATH index may belong to different classes of dynamical behaviour. We identify proteins with the biggest forces and show that they belong to few topology classes. We determine which protein segments act as mechanical clamps and show that, in most cases, they correspond to long stretches of parallel β-strands, but other mechanisms are also possible. (topical review)

  19. Universal Linear Motor Driven Leg Press Dynamometer and Concept of Serial Stretch Loading.

    Science.gov (United States)

    Hamar, Dušan

    2015-08-24

    Paper deals with backgrounds and principles of universal linear motor driven leg press dynamometer and concept of serial stretch loading. The device is based on two computer controlled linear motors mounted to the horizontal rails. As the motors can keep either constant resistance force in selected position or velocity in both directions, the system allows simulation of any mode of muscle contraction. In addition, it also can generate defined serial stretch stimuli in a form of repeated force peaks. This is achieved by short segments of reversed velocity (in concentric phase) or acceleration (in eccentric phase). Such stimuli, generated at the rate of 10 Hz, have proven to be a more efficient means for the improvement of rate of the force development. This capability not only affects performance in many sports, but also plays a substantial role in prevention of falls and their consequences. Universal linear motor driven and computer controlled dynamometer with its unique feature to generate serial stretch stimuli seems to be an efficient and useful tool for enhancing strength training effects on neuromuscular function not only in athletes, but as well as in senior population and rehabilitation patients.

  20. Towards nanopatterning by femtosecond laser ablation of pre-stretched elastomers

    International Nuclear Information System (INIS)

    Surdo, Salvatore; Piazza, Simonluca; Ceseracciu, Luca; Diaspro, Alberto; Duocastella, Martí

    2016-01-01

    Graphical abstract: - Highlights: • We present a new approach to increase the focusing capabilities of optical systems. • Laser patterning is performed over a stretched elastomeric membrane. • After releasing stress, patterns shrink according to the applied strain. • Minimum feature size is controlled by strain, enabling sub-diffraction patterning. - Abstract: Diffraction limits the focusing capabilities of an optical system seriously constraining the use of lasers for nanopatterning. In this work, we present a novel and simple approach to reduce the minimum feature size of a laser-direct write system by ablating a pre-stretched material. In particular, by focusing and scanning a femtosecond laser beam on the surface of a uniaxially pre-stretched elastomeric membrane we are able to obtain microstructures according to a desired pattern. After removing the stress applied to the elastomer, the membrane relaxes to its original size and the ablated patterns shrink while preserving their shape. In this way, the minimum feature size that is typically determined by the optical properties of the focusing system can be now controlled by the strain applied to the elastomer during the ablation process. We demonstrate this approach by ablating lines on a stretchable polymeric membrane at different strain conditions. Experimental results are in good agreement with theoretical predictions. The proposed method opens up new interesting possibilities for the rapid prototyping of micro- and nano-structures suitable for a wide range of applications such as soft-lithography, micro-/nano-fluidics and lab-on-chip.