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How Are University Gyms Used by Staff and Students? A Mixed-Method Study Exploring Gym Use, Motivation, and Communication in Three UK Gyms
Get PDFThis study examined university gym use by staff and students using mixed methods: participant observation and an e-survey. Research in three UK universities entailed 16 observation sessions and an e-survey that reached 3396 students and staff. The research focused on gym use, the gym environment, the presentation of the self, and social interaction within gym spaces. The gyms were found to have a difficult role to play in providing functionality for some, while helping others to be active and minimize feelings of isolation and lack of control. This led to these gyms developing spaces of exercise rather than therapeutic spaces, and divisions in use of space, with some areas rarely used and often highly gendered, resulting in contested meanings produced within Healthy University discourses and physical activities
Acute cardiovascular responses to resistance exercise in anabolic steroids users: A preliminary investigation
Get PDFObjectives.
Anabolic steroid (AS) use has increased in recent years, but the cardiovascular consequences for users is not fully understood.
Equipment and Methods.
Resistance trained males (AS = 7, age = 29 ± 5; NAS = 6, age = 25 ± 1 yrs) undertook a resistance exercise session with echocardiographic measures and cardiac biomarkers taken pre and post exercise (cTnI, NT-proBNP).
Results.
A significant decrease in early diastolic tissue velocity (E’) (AS = 13 ± 1 vs 11 ± 3, NAS = 13 ± 2 vs12 ± 1 cm.s−1), late diastolic tissue velocity (A’) (AS = 9 ± 2 vs 8 ± 1, NAS = 8 ± 1 vs 8 ± 1 cm.s−1), E’:A’ (AS = 1.63 vs 1.21, NAS = 1.71 vs 1.62) and E:A (AS = 1.61 vs 1.19, NAS = 1.63 vs 1.29) with an increase in late dia < stolic filling velocity (A) (AS = 53 ± 8 vs 65 ± 11, NAS = 51 ± 3 vs 57 ± 9 cm.s−1) were seen in both groups post-exercise. A significant decrease in left ventricular end-systolic volume (LVESV) (AS = 48 ± 16 vs 45 ± 12, NAS = 51 ± 9 vs 43 ± 11 ml) was seen post-exercise with maintenance of ejection fraction (EF). There was a significant group effect on diastolic blood pressure (BP) (AS = 74 ± 11 vs 66 ± 7, NAS = 68 ± 6 vs 58 ± 2 mmHg) and basal systolic rotation rate (AS = −61.69 ± 18.38 vs −86.65 ± 17.99, NAS = −63.69 ± 14.72 vs −56.50 ± 2.15 .s−1).
Conclusion.
Despite significant reductions in diastolic measures, with maintenance of systolic function, there was no altered cardiovascular response in the AS users following resistance exercise
A Novel Weakly-supervised approach for RGB-D-based Nuclear Waste Object Detection and Categorization
Get PDFThis paper addresses the problem of RGBD-based detection and categorization of waste objects for nuclear decommissioning. To enable autonomous robotic manipulation for nuclear decommissioning, nuclear waste objects must be detected and categorized. However, as a novel industrial application, large amounts of annotated waste object data are currently unavailable. To overcome this problem, we propose a weakly-supervised learning approach which is able to learn a deep convolutional neural network (DCNN) from unlabelled RGBD videos while requiring very few annotations. The proposed method also has the potential to be applied to other household or industrial applications. We evaluate our approach on the Washington RGBD object recognition benchmark, achieving the state-of-the-art performance among semi-supervised methods. More importantly, we introduce a novel dataset, i.e. Birmingham nuclear waste simulants dataset, and evaluate our proposed approach on this novel industrial object recognition challenge. We further propose a complete real-time pipeline for RGBD-based detection and categorization of nuclear waste simulants. Our weakly-supervised approach has demonstrated to be highly effective in solving a novel RGB-D object detection and recognition application with limited human annotations
A Learned Polyalphabetic Decryption Cipher
Get PDFThis paper examines the use of machine learning algorithms to model polyalphabetic ciphers for decryption. The focus of this research is to train and evaluate different machine learning algorithms to model the polyalphabetic cipher. The algorithms that have been selected are: (1) hill climbing; (2) genetic algorithm; (3) simulated annealing; and (4), random optimisation. The resulting models were deployed in a simulation to decrypt sample codes. The resulting analysis showed that the genetic algorithm was the most effective technique used in with hill climbing as second. Furthermore, both have the potential to be useful for larger problems
Is exercise-based cardiac rehabilitation effective? A systematic review and meta-analysis to re-examine the evidence
Get PDFObjectives: To determine the contemporary effectiveness of exercise-based cardiac rehabilitation (CR) in terms of all-cause mortality, cardiovascular mortality and hospital admissions.
Data sources: Studies included in or meeting the entry criteria for the 2016 Cochrane review of exercise-based CR in patients with coronary artery disease.
Study eligibility criteria: Randomised controlled trials (RCTs) of exercise-based CR versus a no-exercise control whose participants were recruited after the year 2000.
Study appraisal and synthesis methods: Two separate reviewers independently screened the characteristics of studies. One reviewer quality appraised any new studies and assessed their risk of bias using the Cochrane Collaboration’s recommended risk of bias tool. Data were reported as the risk difference (95% CI).
Results: We included 22 studies with 4834 participants (mean age 59.5 years, 78.4% male). We found no differences in outcomes between exercise-based CR and a no-exercise control at their longest follow-up period for: all-cause mortality (19 studies; n=4194; risk difference 0.00, 95% CI −0.02 to 0.01, P=0.38) or cardiovascular mortality (9 studies; n=1182; risk difference −0.01, 95% CI −0.02 to 0.01, P=0.25). We found a small reduction in hospital admissions of borderline statistical significance (11 studies; n=1768; risk difference −0.05, 95% CI −0.10 to −0.00, P=0.05).
Conclusions and implications of key findings: Our analysis indicates conclusively that the current approach to exercise-based CR has no effect on all-cause mortality or cardiovascular mortality, when compared with a no-exercise control. There may be a small reduction in hospital admissions following exercise-based CR that is unlikely to be clinically important
Fovography: A naturalistic imaging media
Get PDFThe aim of our research is to improve the way visual experience is depicted in imaging media by increasing the naturalism of the media. Numerous technical methods for depicting the visual world currently exist. Most of them rely on optical laws that determine the way light rays project onto a plane through an aperture [9]. Physical cameras and computer graphics rendering systems are the most common examples. They are designed to accurately capture or computationally simulate the patterns of light emitted or reflected by objects in the world. The images they produce can be thought of as objectively realistic. However, such images to do not necessarily represent what a human viewer would experience when viewing the same objects; the human visual system is not a camera. While there are some similarities between eyes and cameras, much of what we visually perceive is the result of complex psychological and neurophysiological processing occurring in the visual areas of the brain, for which there is no parallel in current imaging technology [12]. This paper briefly outlines our approach to creating naturalistic imaging media based on the emulation of human visual processes, and how this can improve the way we depict the visual world
Efficacy of an 8-Week Concurrent Strength and Endurance Training Programme on Hand Cycling Performance
Get PDFThe aim of the present study was to investigate the effects of an 8-week concurrent strength and endurance training programme in comparison to endurance training only on several key determinants of hand cycling performance. Five H4 and five H3 classified hand cyclists with at least one year’s hand cycling training history consented to participate in the study. Subjects underwent a battery of tests to establish body mass, body composition, VO2peak, maximum aerobic power, gross mechanical efficiency, maximal upper body strength, and 30 km time trial performance. Subjects were matched into pairs based upon 30 km time trial performance and randomly allocated to either a concurrent strength and endurance or endurance training only, intervention group. Following an 8-week training programme based upon a conjugated block periodisation model, subjects completed a second battery of tests. A mixed model, 2-way analysis of variance (ANOVA) revealed no significant changes between groups. However, the calculation of effect sizes (ES) revealed that both groups demonstrated a positive improvement in most physiological and performance measures with subjects in the concurrent group demonstrating a greater magnitude of improvement in body composition (ES -0.80 vs. -0.22) maximal aerobic power (ES 0.97 vs. 0.28), gross mechanical efficiency (ES 0.87 vs. 0.63), bench press 1 repetition maximum (ES 0.53 vs. 0.33), seated row 1 repetition maximum (ES 1.42 vs. 0.43), and 30 km time trial performance (ES -0.66 vs. -0.30). In comparison to endurance training only, an 8-week concurrent training intervention based upon a conjugated block periodisation model appears to be a more effective training regime for improving the performance capabilities of hand cyclists
A biomechanical comparison of initial sprint acceleration performance and technique in an elite athlete with cerebral palsy and able-bodied sprinters
Get PDFCerebral palsy is known to generally limit range of motion and force producing capability during movement. It also limits sprint performance, but the exact mechanisms underpinning this are not well known. One elite male T36 multiple-Paralympic sprint medallist (T36) and 16 well-trained able-bodied (AB) sprinters each performed 5–6 maximal sprints from starting blocks. Whole-body kinematics (250 Hz) in the block phase and first two steps, and synchronised external forces (1,000 Hz) in the first stance phase after block exit were combined to quantify lower limb joint kinetics. Sprint performance (normalised average horizontal external power in the first stance after block exit) was lower in T36 compared to AB. T36 had lower extensor range of motion and peak extensor angular velocity at all lower limb joints in the first stance after block exit. Positive work produced at the knee and hip joints in the first stance was lower in T36 than AB, and the ratio of positive:negative ankle work produced was lower in T36 than AB. These novel results directly demonstrate the manner in which cerebral palsy limits performance in a competition-specific sprint acceleration movement, thereby improving understanding of the factors that may limit performance in elite sprinters with cerebral palsy
Effect of glutaraldehyde based cross-linking on the viscoelasticity of mitral valve basal chordae tendineae
Get PDFBackground
Mitral valve failure can require repair or replacement. Replacement bioprosthetic valves are treated with glutaraldehyde prior to implantation. The aim of this study was to determine the changes in mechanical properties following glutaraldehyde fixation of mitral valve chordae.
Methods
To investigate the impact of glutaraldehyde on mitral valve chordae, 24 basal chordae were dissected from four porcine hearts. Anterior and posterior basal (including strut) chordae were used. All 24 chordae were subjected to a sinusoidally varying load (mean level 2N, dynamic amplitude 2N) over a frequency range of 0.5–10 Hz before and after glutaraldehyde treatment.
Results
The storage and loss modulus of all chordal types decreased following glutaraldehyde fixation. The storage modulus ranged from: 108 to 119 MPa before fixation and 67.3–87.4 MPa following fixation for basal chordae; 52.3–58.4 MPa before fixation and 47.9–53.5 MPa following fixation for strut chordae. Similarly, the loss modulus ranged from: 5.47 to 6.25 MPa before fixation and 3.63–4.94 MPa following fixation for basal chordae; 2.60–2.97 MPa before fixation and 2.31–2.93 MPa following fixation for strut chordae.
Conclusion
The viscoelastic properties of mitral valve chordae are affected by glutaraldehyde fixation; in particular, the reduction in storage moduli decreased with an increase in chordal diameter
Initial Validation of the Teacher-Created Empowering and Disempowering Motivational Climate Questionnaire in Physical Education
Get PDFPurpose: Guided by Duda’s hierarchical conceptualization of the motivational climate that draws from self-determination and achievement goal theories, this study provides initial evidence of the psychometric properties of the Empowering and Disempowering Motivational Climate Questionnaire in physical education (EDMCQ-PE). Method: Questionnaire based with two samples of Welsh secondary school pupils. Results: Exploratory structural equation modeling provided a better fit of the data to the hypothesized model than confirmatory factor analysis. Moreover, a two-factor composite (i.e., empowering and disempowering) lower-order model provided an acceptable fit and clear parameter estimates. This two-factor model also demonstrated scalar gender measurement invariance. Discussion: The evidence from this study suggests the EDMCQ-PE is a promising scale for the assessment of secondary school pupils’ perceptions of the empowering and disempowering features of the motivational climate created by their physical education teachers. Conclusion: Moving forward, the statistical approach employed in this paper can inform future studies that develop questionnaire methodology in physical education and from an applied perspective; the EDMCQ-PE can be used by researchers and teachers to assess the motivational climate in PE and help inform the pedagogy underpinning teachers’ classes