Energy costs and performance of transfemoral amputees and non-amputees during walking and running: A pilot study

2016 ◽  
Vol 41 (5) ◽  
pp. 484-491 ◽  
Author(s):  
Larry J Mengelkoch ◽  
Jason T Kahle ◽  
M Jason Highsmith
Keyword(s):  
Specific Energy ◽  
Repeated Measures ◽  
Energy Costs ◽  
Limited Information ◽  
Prosthetic Foot ◽  
Walking Performance ◽  
Transfemoral Amputees ◽  
Gait Economy ◽  
And Performance ◽  
Walking Speeds

Background:Limited information is available concerning the effects of prosthetic foot components on energy costs and ambulatory performance for transfemoral amputees.Objectives:Compare energy costs (VO2; gait economy) and ambulatory performance (self-selected walking speeds, self-selected running speeds, peak running speeds) differences during walking and running for transfemoral amputees and matched, non-amputee runners.Study design:Repeated measures.Methods:Transfemoral amputees were accommodated and tested with three prosthetic feet: conventional foot, solid-ankle cushioned heel (SACH); energy storing and return foot, Renegade; and running-specific energy storing and return foot, Nitro.Results:During walking, VO2was similar between transfemoral amputees but was increased compared to controls. Self-selected walking speeds were slower for SACH compared to Renegade and Nitro. For transfemoral amputees, gait economy was decreased and self-selected walking speeds were slower compared to controls. During fixed running speeds, transfemoral amputees ran using Nitro, and VO2was greater compared to controls. Transfemoral amputees ran at self-selected running speeds using Renegade and Nitro. Self-selected running speeds were slower for Renegade compared to Nitro. For transfemoral amputees, gait economy was decreased and self-selected running speeds were slower compared to controls. VO2peak was similar between transfemoral amputees and controls, but controls achieved greater peak running speeds and % grade.Conclusion:Energy costs were greater and ambulatory performance was lower for transfemoral amputees compared to matched, non-amputee controls for all prosthetic foot conditions.Clinical relevanceBoth types of energy storing and return feet may improve walking performance for transfemoral amputees by providing faster self-selected walking speeds. For transfemoral amputees interested in performing vigorous running (exercise and running competition), clinicians should recommend a running-specific energy storing and return foot.

I Like Myself, I Really Do (at Least Right Now)

2020 ◽  
Vol 36 (1) ◽  
pp. 196-206 ◽  
Author(s):  
Almut Rudolph ◽  
Michela Schröder-Abé ◽  
Astrid Schütz
Keyword(s):  
Construct Validity ◽  
Performance Feedback ◽  
Repeated Measures ◽  
Temporal Stability ◽  
Social Feedback ◽  
Student Sample ◽  
Empirically Supported ◽  
Good Internal Consistency ◽  
And Performance ◽  
Induced Changes

Abstract. In five studies, we evaluated the psychometric properties of a revised German version of the State Self-Esteem Scale (SSES; Heatherton & Polivy, 1991 ). In Study 1, the results of a confirmatory factor analysis on the original scale revealed poor model fit and poor construct validity in a student sample that resembled those in the literature; thus, a revised 15-item version was developed (i.e., the SSES-R) and thoroughly validated. Study 2 showed a valid three-factor structure (Performance, Social, and Appearance) and good internal consistency of the SSES-R. Correlations between subscales of trait and state SE empirically supported the scale’s construct validity. Temporal stability and intrapersonal sensitivity of the scale to naturally occurring events were investigated in Study 3. Intrapersonal sensitivity of the scale to experimentally induced changes in state SE was uncovered in Study 4 via social feedback (acceptance vs. rejection) and performance feedback (positive vs. negative). In Study 5, the scale’s interpersonal sensitivity was confirmed by comparing depressed and healthy individuals. Finally, the usefulness of the SSES-R was demonstrated by assessing SE instability as calculated from repeated measures of state SE.

Probability-Based and Measurement-Related Hypotheses With Full Restriction for Investigations by Means of Confirmatory Factor Analysis

Methodology ◽  
2011 ◽  
Vol 7 (4) ◽  
pp. 157-164
Author(s):  
Karl Schweizer
Keyword(s):  
Factor Analysis ◽  
Confirmatory Factor Analysis ◽  
Cognitive Processing ◽  
Latent Variables ◽  
Repeated Measures ◽  
Latent Variable ◽  
Model Fit ◽  
Repeated Measures Data ◽  
Confirmatory Factor ◽  
And Performance

Probability-based and measurement-related hypotheses for confirmatory factor analysis of repeated-measures data are investigated. Such hypotheses comprise precise assumptions concerning the relationships among the true components associated with the levels of the design or the items of the measure. Measurement-related hypotheses concentrate on the assumed processes, as, for example, transformation and memory processes, and represent treatment-dependent differences in processing. In contrast, probability-based hypotheses provide the opportunity to consider probabilities as outcome predictions that summarize the effects of various influences. The prediction of performance guided by inexact cues serves as an example. In the empirical part of this paper probability-based and measurement-related hypotheses are applied to working-memory data. Latent variables according to both hypotheses contribute to a good model fit. The best model fit is achieved for the model including latent variables that represented serial cognitive processing and performance according to inexact cues in combination with a latent variable for subsidiary processes.

scholarly journals Comparison of Starts and Turns between Individual and Relay Swimming Races

2021 ◽  
Vol 18 (9) ◽  
pp. 4740
Author(s):  
Xiao Qiu ◽  
Blanca De la Fuente ◽  
Alberto Lorenzo ◽  
Santiago Veiga
Keyword(s):  
Repeated Measures ◽  
Specific Training ◽  
Flight Phase ◽  
Lower Performance ◽  
Start Section ◽  
And Performance

The present study investigated swimmers’ performances on the starting and turning segments between individual and relay races. A total number of 72 race performances of the same swimmers in both relay 4 × 100 m finals (freestyle, medley, and mixed freestyle) and individual 100 m finals or semi-finals (butterfly, breaststroke, and freestyle) from the LEN European Swimming Championships were compared with repeated measures MANOVA. Swimmers performed 5–7% faster starts in the relay than in the corresponding individual events, despite no differences in the flight phase and a lower performance (shorter distances and slower velocities) on the underwater start section. The 15 m turn times were slower in the butterfly relay races although no specific differences in the underwater parameters were observed. These results suggest that specific training of the starting and turning segments should be performed under relay conditions to optimise pacing and performance in the underwater sections.

The Effects of the BAILAMOSTM Dance Program on Physical Activity Levels and Cognition of Older Latino Adults: A Pilot Study

2021 ◽  
pp. 089826432110209
Author(s):  
Guilherme M. Balbim ◽  
Susan Aguiñaga ◽  
Olusola A. Ajilore ◽  
Eduardo E. Bustamante ◽  
Kirk I. Erickson ◽  
...  
Keyword(s):  
Physical Activity ◽  
Pilot Study ◽  
Health Education ◽  
Repeated Measures ◽  
Activity Levels ◽  
Cognitive Health ◽  
Physical Activity Levels ◽  
Global Cognition ◽  
Latino Adults ◽  
And Performance

Objective: To investigate the effects of the BAILAMOSTM dance program on physical activity (PA), cardiorespiratory, and cognitive health. Methods: A parallel, two-armed pilot study was conducted with 57 older Latinos randomized to the BAILAMOSTM dance program ( n = 28) or health education (HE) ( n = 29). We conducted two- and three-way repeated-measures ANOVAs. Results: BAILAMOSTM participants increased participation in leisure moderate-to-vigorous PA (LMVPA) ( F[1,53] = 3.17, p = .048, η2 G = .01) and performance in global cognition relative to HE participants ( F[1,52] = 4.19, p = .045, η2 G = .01). Attendance moderated increases in moderate PA, MVPA, LMVPA, and total PA ( p < .05). Participants of both groups with ≥75% attendance increased participation in PA. Among participants with <75% attendance, BAILAMOSTM participants increased PA relative to HE. Discussion: BAILAMOSTM positively impacted self-reported PA and global cognition in older Latinos. Even smaller doses of dance appear to impact self-reported PA levels.

scholarly journals ICT evaluation models and performance of medium and small enterprises

2014 ◽  
Vol 20 (1-2) ◽  
pp. 9-24
Author(s):  
Anass Bayaga ◽  
Emmanuel O. Adu
Keyword(s):  
Risk Management ◽  
Analysis Of Variance ◽  
Repeated Measures ◽  
Operational Risk ◽  
Small Enterprises ◽  
Operational Risk Management ◽  
Evaluation Models ◽  
Ict Adoption ◽  
And Performance ◽  
Medium And Small Enterprises

Abstract Building on prior research related to (1) impact of information communication technology (ICT) and (2) operational risk management (ORM) in the context of medium and small enterprises (MSEs), the focus of this study was to investigate the relationship between (1) ICT operational risk management (ORM) and (2) performances of MSEs. To achieve the focus, the research investigated evaluating models for understanding the value of ICT ORM in MSEs. Multiple regression, Repeated-Measures Analysis of Variance (RM-ANOVA) and Repeated-Measures Multivariate Analysis of Variance (RM-MANOVA) were performed. The findings of the distribution revealed that only one variable made a significant percentage contribution to the level of ICT operation in MSEs, the Payback method (β = 0.410, p < .000). It may thus be inferred that the Payback method is the prominent variable, explaining the variation in level of evaluation models affecting ICT adoption within MSEs. Conclusively, in answering the two questions (1) degree of variability explained and (2) predictors, the results revealed that the variable contributed approximately 88.4% of the variations in evaluation models affecting ICT adoption within MSEs. The analysis of variance also revealed that the regression coefficients were real and did not occur by chance

Scaling Membership of Byzantine Consensus

2020 ◽  
Vol 38 (3-4) ◽  
pp. 1-31
Author(s):  
Burcu Canakci ◽  
Robbert Van Renesse
Keyword(s):  
Fault Tolerant ◽  
Initial Conditions ◽  
Low Latency ◽  
Energy Costs ◽  
Prior Work ◽  
Improve Performance ◽  
Consensus Protocol ◽  
Normal Case ◽  
Network Topologies ◽  
And Performance

Scaling Byzantine Fault Tolerant (BFT) systems in terms of membership is important for secure applications with large participation such as blockchains. While traditional protocols have low latency, they cannot handle many processors. Conversely, blockchains often have hundreds to thousands of processors to increase robustness, but they typically have high latency or energy costs. We describe various sources of unscalability in BFT consensus protocols. To improve performance, many BFT protocols optimize the “normal case,” where there are no failures. This can be done in a modular fashion by wrapping existing BFT protocols with a building block that we call alliance . In normal case executions, alliance can scalably determine if the initial conditions of a BFT consensus protocol predetermine the outcome, obviating running the consensus protocol. We give examples of existing protocols that solve alliance. We show that a solution based on hypercubes and MAC s has desirable scalability and performance in normal case executions, with only a modest overhead otherwise. We provide important optimizations. Finally, we evaluate our solution using the ns3 simulator and show that it scales up to thousands of processors and compare with prior work in various network topologies.

A New Aluminium Silicon-Boron Nitride Abradable for Compressor Components

1998 ◽  
Author(s):  
K. Boddenberg ◽  
B. Kock ◽  
M. Dorfman ◽  
L. Russo ◽  
M. Nestler
Keyword(s):  
Boron Nitride ◽  
Raw Materials ◽  
Electrical Energy ◽  
Air Separation ◽  
Energy Costs ◽  
Performance Improvements ◽  
And Performance ◽  
Materials Used ◽  
Abradable Coatings ◽  
Optimization And Performance

Abstract Air separation plants use centrifugal compressors where air and electrical energy are the only raw materials used in the production process. So energy costs play a crucial role and the compressors are heavily penalized when guaranteed performance levels are not achieved. In order to better generate performance, abradable coatings, previously used in the gas turbine industry, have been designed into turbocompressors. This paper will show the optimization and performance improvements of a new aluminium silicon-boron nitride material.

scholarly journals 1 Physiological and performance recovery after fourteen hours of feed restriction or transportation in Holstein bulls fed high concentrate diets

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 2-3
Author(s):  
Sonia Marti ◽  
Elena Garcia ◽  
Christine Gerard ◽  
Joan Grau ◽  
Nicolas Cirier ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Feed Restriction ◽  
Amyloid A ◽  
Performance Recovery ◽  
Treatment Data ◽  
Access To Water ◽  
Holstein Calves ◽  
Holstein Bulls ◽  
And Performance ◽  
Beta Hydroxybutyrate

Abstract One hundred and eight Holstein calves (225 ± 1.1 kg and 187 ± 5.2 d) were used to evaluate the physiological and performance recovery after 14 h transportation or feed restriction. Calves were distributed into 6 pens (2 pens/treatment) according to control (CTR, n = 36) calves with ad libitum access to concentrate, straw and water; restricted (RES, n = 36) calves with concentrate restriction but with access to water and straw for 14 h; and transported (TRA, n = 36) calves that were loaded into a trailer and transported without feed or water for 14 h. On days 0, 7, 21, and 35 BW was recorded. Concentrate intake were recorded daily. Blood samples for non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHBA), and serum amyloid-A (SAA) were collected at -24, -14, 0 h, and 6, 24, and 168 h post-treatment. Data were analyzed using mixed models with repeated measures. At 24 h, RES and TRA had greater (P &lt; 0.05) concentrate intake compared with CTR. However, from d 7 to 35 after treatments, only TRA had similar concentrate intake than CTR, while RES had lesser (P &lt; 0.05) concentrate intake than CTR and TRA. RES at 6 h had greater (P &lt; 0.05) NEFA concentrations than TRA, and NEFA concentrations were still higher for the RES and TRA groups than those for the CTR after 24 h. After 24 h concentrations of serum BHBA for TRA and RES were significantly greater (P &lt; 0.05) when compared with those for the CTR. Serum concentration of SAA for TRA and RES was greater (P &lt; 0.05) than CTR until 168 h. Results showed similar effects of 14 h of feed restriction and transportation of calves on serum anorexia and inflammation parameters; however, feed intake was recovered after d 35 in transported calves but not in feed restricted calves without transportation.

scholarly journals Beta alanine supplementation effects on metabolic contribution and swimming performance

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Matheus Silva Norberto ◽  
Ricardo Augusto Barbieri ◽  
Danilo Rodrigues Bertucci ◽  
Ronaldo Bucken Gobbi ◽  
Eduardo Zapaterra Campos ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Energy Demand ◽  
Swimming Performance ◽  
Controlled Study ◽  
Double Blind ◽  
Repeated Measures Anova ◽  
Beta Alanine ◽  
Before And After ◽  
The Difference ◽  
And Performance

Abstract Background Investigations of β-alanine supplementation shows effects on metabolic (aerobic and anaerobic) participation and performance on swimming by a possible blood acidosis buffering. Considering this background, the objective of the present study was to analyze the effects of β-alanine supplementation on metabolic contribution and performance during 400-m swim. Methods Thirteen competitive swimmers underwent a 6-week, double-blind placebo-controlled study, ingesting 4.8 g.day− 1 of β-alanine or placebo. Before and after the supplementation period, the total anaerobic contribution (TAn) and 30-s all-out tethered swimming effort (30TS) were assessed. Anaerobic alactic (AnAl) and lactic energy (AnLa) was assumed as the fast component of excess post-exercise oxygen consumption and net blood lactate accumulation during exercise (∆[La−]), respectively. Aerobic contribution (Aer) was determined by the difference between total energy demand and TAn. In addition to conventional statistical analysis (Repeated measures ANOVA; p > 0.05), a Bayesian repeated measures ANOVA was used to evidence the effect probability (BFincl). Results No differences and effects were found between groups, indicating no supplementation effects. Repeated measures ANOVA, with confirmation of effect, was indicate reduce in ∆Lactate (p: 0.001; BFincl: 25.02); absolute AnLa (p: 0.002; BFincl: 12.61), fatigue index (p > 0.001; BFincl: 63.25) and total anaerobic participation (p: 0.008; BFincl: 4.89). Conclusions Thus, the results demonstrated that all changes presented were evidenced as a result of exposure to the training period and β-alanine supplementation doesn’t affect metabolic contribution and performance during 400-m freestyle.

Gait worsening and the microlesion effect following deep brain stimulation for essential tremor

2019 ◽  
Vol 90 (8) ◽  
pp. 913-919 ◽  
Author(s):  
Ryan Roemmich ◽  
Jaimie A Roper ◽  
Robert S Eisinger ◽  
Jackson N Cagle ◽  
Lauren Maine ◽  
...  
Keyword(s):  
Deep Brain Stimulation ◽  
Essential Tremor ◽  
Brain Stimulation ◽  
Repeated Measures ◽  
Walking Speed ◽  
Stimulation Parameters ◽  
Gait Parameters ◽  
Before And After ◽  
Walking Speeds ◽  
Deep Brain

ObjectiveTo investigate the effects of unilateral thalamic deep brain stimulation (DBS) on walking in persons with medication-refractory essential tremor (ET).MethodsWe performed laboratory-based gait analyses on 24 persons with medication-refractory ET before and after unilateral thalamic DBS implantation. Normal and tandem walking parameters were analysed across sessions (PRE-DBS/DBS OFF/DBS ON) by repeated measures analyses of variance. Pearson’s correlations assessed whether changes in walking after DBS were global (ie, related across gait parameters). Baseline characteristics, lead locations and stimulation parameters were analysed as possible contributors to gait effects.ResultsDBS minimally affected gait at the cohort level. However, 25% of participants experienced clinically meaningful gait worsening. Walking speed decreased by >30% in two participants and by >10% in four others. Decreased walking speed correlated with increased gait variability, indicating global gait worsening in affected participants. The worsening persisted even after the stimulation was turned off. Participants with worse baseline tandem walking performance may be more likely to experience post-DBS gait worsening; the percentage of tandem missteps at baseline was nearly three times higher and tandem walking speeds were approximately 30% slower in participants who experienced gait worsening. However, these differences in tandem walking in persons with gait worsening as compared with those without worsening were not statistically significant. Lead locations and stimulation parameters were similar in participants with and without gait worsening.ConclusionGlobal gait worsening occurred in 25% of participants with unilateral DBS for medication-refractory ET. The effect was present on and off stimulation, likely indicating a microlesion effect.

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