306 research outputs found

    Effects of different vibration frequencies, amplitudes and contraction levels on lower limb muscles during graded isometric contractions superimposed on whole body vibration stimulation

    Get PDF
    Background: Indirect vibration stimulation, i.e., whole body vibration or upper limb vibration, has been investigated increasingly as an exercise intervention for rehabilitation applications. However, there is a lack of evidence regarding the effects of graded isometric contractions superimposed on whole body vibration stimulation. Hence, the objective of this study was to quantify and analyse the effects of variations in the vibration parameters and contraction levels on the neuromuscular responses to isometric exercise superimposed on whole body vibration stimulation. Methods: In this study, we assessed the 'neuromuscular effects' of graded isometric contractions, of 20%, 40%, 60%, 80% and 100% of maximum voluntary contraction, superimposed on whole body vibration stimulation (V) and control (C), i.e., no-vibration in 12 healthy volunteers. Vibration stimuli tested were 30 Hz and 50 Hz frequencies and 0.5 mm and 1.5 mm amplitude. Surface electromyographic activity of the vastus lateralis, vastus medialis and biceps femoris were measured during V and C conditions with electromyographic root mean square and electromyographic mean frequency values used to quantify muscle activity and their fatigue levels, respectively. Results: Both the prime mover (vastus lateralis) and the antagonist (biceps femoris) displayed significantly higher (P < 0.05) electromyographic activity with the V than the C condition with varying percentage increases in EMG root-mean-square (EMGrms) values ranging from 20% to 200%. For both the vastus lateralis and biceps femoris, the increase in mean EMGrms values depended on the frequency, amplitude and muscle contraction level with 50 Hz-0.5 mm stimulation inducing the largest neuromuscular activity. Conclusions: These results show that the isometric contraction superimposed on vibration stimulation leads to higher neuromuscular activity compared to isometric contraction alone in the lower limbs. The combination of the vibration frequency with the amplitude and the muscle tension together grades the final neuromuscular output.Peer reviewe

    A study on the bending of laminated glass under blast loading

    Get PDF
    Background: The bending behaviour of laminated glass plays an important role in determining its overall response to blast loading. It is costly and difficult to characterise the bending behaviour by carrying out full-scale blast tests, therefore an alternative method is required. Objective: The objective of this study is to understand the response of laminated glass under high-rate bending in the laboratory at rates representative of blast loading. Methods: In this paper a novel testing method is presented in which laminated glass strips of 700 mm long by 60 mm wide are tested up to speeds of 10 m/s in the laboratory. The laminated glass is accelerated to speeds comparable to blast loading and then brought to rest at its edges to mimic impulsive blast loading conditions. Different interlayer thickness, impact speeds, and boundary conditions were explored. Additionally, modelling methods were used to study the flexural rigidity of post-cracked laminated glass. Results: From the experiments it was found that the interlayer thickness plays a key role in determining whether the dominant failure mechanism is de-bonding of interlayer from the glass or interlayer tearing. In addition, it was found that by allowing the frame to bend under loading, the laminated glass can carry greater loads without failure. Finally, an iterative method was used to quantify the flexural rigidity of post-cracked laminated glass depending on the speed of travel. This is a novel finding as it is usually assumed that laminated glass behaves like a membrane in the post-cracked phase of the response. Conclusion: In modelling and design of laminated glass structures under blast loading, post-crack flexural rigidity must be taken into account. Additionally, having novel frame designs to add further load bearing capacity to the framing members, plays a key role in reducing the load intensity on the laminated glass structure

    Depression and Prostate Cancer: Examining Comorbidity and Male-Specific Symptoms

    Get PDF
    © The Author(s) 2018. Depression in men with prostate cancer is a significant and complex issue that can challenge clinicians’ diagnostic efforts. The objective of the current study was to evaluate prototypic and male-specific depression symptoms and suicidal ideation in men with a diagnosis of prostate cancer relative to those with and without comorbidity. The Patient Health Questionnaire-9 (PHQ-9) and Male Depression Risk Scale-22 (MDRS-22) were completed online along with demographic and background variables by 100 men with a diagnosis of prostate cancer (n = 54 prostatectomy, n = 33 receiving active treatment). Hierarchical logistic regression was used to examine recent (past 2 weeks) suicide ideation. Over one-third of the sample (38%) reported a comorbidity, and this group had significantly higher total depression scores on the PHQ-9 (Cohen’s d = 0.65), MDRS-22 emotion suppression (d = 0.35), and drug use subscales (d = 0.38) compared to respondents without comorbidity. A total of 14% reported recent suicidal ideation, of which 71.4% of cases were identified by the PHQ-9 “moderate” cut-off, and 85.7% of cases were identified by the MDRS-22 “elevated” cut-off. After control variables, MDRS-22 subscales accounted for 45.1% of variance in recent suicidal ideation. While limited by the exclusive use of self-report data, findings point to the potential benefits of evaluating male-specific symptoms as part of depression and suicide risk screening in men with prostate cancer and the need to be mindful of the heightened risk for depression among men with prostate cancer who have comorbidity

    Reaction forces of laminated glass windows subject to blast loads

    Get PDF
    Several blast trials on laminated glass windows have been performed in the past, using both full field 3D Digital Image Correlation and strain gauges located on the supporting structure to collect information on the glass pane behaviour. The data obtained during three blast experiments were employed to calculate reaction forces throughout the perimeter supports both before and after the fracture of the glass layers. The pre-crack experimental data were combined with finite element modelling results to achieve this, whilst solely experimental results were employed for post-cracked reactions. The results for the three blast experiments were compared to identify similarities in their behaviour. It is intended that the results can be used to improve the existing spring–mass systems used for the design of blast resistant windows

    The effects of home-based exercise therapy for breast cancer-related fatigue induced by radical radiotherapy

    Get PDF
    Background Radiotherapy (RT) can lead to cancer-related fatigue (CRF) and decreased health-related quality of life (HRQoL) in breast cancer patients. The purpose of this trial was to examine the feasibility and efficacy of a home-based resistance and aerobic exercise intervention for reducing CRF and improving HRQoL in breast cancer patients during RT. Methods Women with breast cancer (N = 106) commencing RT were randomized to 12 weeks of home-based resistance and aerobic exercise (EX) or usual care/control (CON). The primary endpoint was CRF, with secondary endpoints of HRQoL, sleep duration and quality, and physical activity. Measurements were undertaken prior to RT, at completion of RT (~ 6 weeks), at completion of the intervention (12 weeks), and 6 and 12 months after RT completion, while CRF was also measured weekly during RT. Results Eighty-nine women completed the study (EX = 43, CON = 46). Over the 12-week intervention, EX completed 1–2 resistance training sessions and accumulated 30–40 min of aerobic exercise weekly. For CRF, EX had a quicker recovery both during and post-RT compared to CON (p < 0.05). Moreover, there was a significant difference in HRQoL between groups at RT completion, with HRQoL unchanged in CON and higher in EX (p < 0.05). There was no change in sleep duration or quality for either group and there were no exercise-related adverse effects. Conclusions Home-based resistance and aerobic exercise during RT is safe, feasible, and effective in accelerating CRF recovery and improving HRQoL. Improvements in CRF and HRQoL for these patients can be achieved with smaller exercise dosages than stated in the generic recommendations for breast cancer

    Effects of Different Exercise Modalities on Fatigue in Prostate Cancer Patients Undergoing Androgen Deprivation Therapy: A Year-long Randomised Controlled Trial.

    Full text link
    BACKGROUND: Physical exercise mitigates fatigue during androgen deprivation therapy (ADT); however, the effects of different exercise prescriptions are unknown. OBJECTIVES: To determine the long-term effects of different exercise modes on fatigue in prostate cancer patients undergoing ADT. DESIGN, SETTING, AND PARTICIPANTS: Between 2009 and 2012, 163 prostate cancer patients aged 43-90 y on ADT were randomised to exercise targeting the musculoskeletal system (impact loading+resistance training; ILRT; n=58), the cardiovascular and muscular systems (aerobic+resistance training; ART; n=54), or to usual care/delayed exercise (DEL; n=51) for 12 mo across university-affiliated exercise clinics in Australia. INTERVENTION: Supervised ILRT for 12 mo, supervised ART for 6 mo followed by a 6-mo home program, and DEL received a printed booklet on exercise information for 6 mo followed by 6-mo stationary cycling exercise. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Fatigue was assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 36 and vitality using the Short Form-36. Analysis of variance was used to compare outcomes for groups at 6 mo and 12 mo. RESULTS AND LIMITATIONS: Fatigue was reduced (p=0.005) in ILRT at 6 mo and 12 mo (∼5 points), and in ART (p=0.005) and DEL (p=0.022) at 12 mo. Similarly, vitality increased for all groups (p≤0.001) at 12 mo (∼4 points). Those with the highest levels of fatigue and lowest vitality improved the most with exercise (ptrend<0.001). A limitation was inclusion of mostly well-functioning individuals. CONCLUSIONS: Different exercise modes have comparable effects on reducing fatigue and enhancing vitality during ADT. Patients with the highest levels of fatigue and lowest vitality had the greatest benefits. PATIENT SUMMARY: We compared the effects of different exercise modes on fatigue in men on androgen deprivation therapy. All exercise programs reduced fatigue and enhanced vitality. We conclude that undertaking some form of exercise will help reduce fatigue, especially in those who are the most fatigued

    Piccole capitali creative

    Get PDF
    Nel secolo urbano che abbiamo di fronte, la citt\ue0 sar\ue0 lo scenario della competizione delle energie, delle risorse umane, delle intelligenze collettive e della creativit\ue0 per la costruzione di un\u2019evoluzione pi\uf9 compatibile con le identit\ue0 e le vocazioni e pi\uf9 sostenibile rispetto alle risorse ed alle sensibilit\ue0 del territorio. I segnali delle sue forme, delle sue relazioni e delle sue identit\ue0 sono gi\ue0 evidenti in alcune citt\ue0 del presente ed ad essi sono dedicate numerose ricerche urbanistiche, sociologiche ed economiche. Ma i segnali sono evidenti e trasmettono ispirazioni e stimoli anche a chi osserva la citt\ue0 per mestiere di progettista, di pianificatore, di stratega dello sviluppo. Il XXI secolo sar\ue0 l\u2019era indiscussa delle citt\ue0 e su di esse si misurer\ue0 lo sviluppo delle nazioni. Per la prima volta, pi\uf9 della met\ue0 della popolazione mondiale vivr\ue0 nelle citt\ue0, in Europa oggi la cifra \ue8 gi\ue0 di oltre il 75%, e nei paesi in via di sviluppo raggiunger\ue0 velocemente il 50%. Il mondo si svilupper\ue0 sia attorno a grandi megalopoli da decine di milioni di abitanti, ma anche attorno a citt\ue0 metropolitane, a conurbazioni diffuse e ad armature di micropoli: all\u2019armatura urbana delle citt\ue0 globali si annoder\ue0, soprattutto in Europa, l\u2019armatura delle citt\ue0 di secondo livello, produttrici di visioni alternative rispetto all\u2019esplosione delle megalopoli. L\u2019armatura urbana europea di secondo livello \u2013 le piccole capitali, sempre pi\uf9 citt\ue0-porta \u2013 si delinea come annodata attorno a \u201ccitt\ue0 della cultura\u201d, nel senso di citt\ue0 non solo detentrici di risorse culturali profonde lasciate dal palinsesto della storia, ma anche produttrici di nuova cultura: le culture-based competition cities saranno, infatti, quelle citt\ue0 in grado di competere nel panorama internazionale attraverso la valorizzazione e la promozione della propria identit\ue0 culturale, sia consolidata che in evoluzione

    A comparison of catch phase force-time characteristics during clean derivatives from the knee

    Get PDF
    The aim of this study was to compare load-absorption force-time characteristics of the clean from the knee (CK), power clean from the knee (PCK) and clean pull from the knee (CPK). Ten collegiate athletes (age 27.5 ± 4.2 years; height 180.4 ± 6.7 cm; mass 84.4 ± 7.8 kg), performed three repetitions each of the CK, PCK and CPK with 90% of their 1RM power clean on a force platform. The CK load-absorption duration (0.95 ± 0.35 s) was significantly longer compared to the CPK (0.44 ± 0.15 s; p 0.05, d = 1.08), with no differences between PCK and CPK (p > 0.05, d = 0.91). The CPK demonstrated the greatest mean force (2039 ± 394 N), which was significantly greater than the PCK (1771 ± 325 N; p = 0.012, d = 0.83), but not significantly different to the CK (1830 ± 331 N; p > 0.05, d = 0.60); CK and PCK were not different (p > 0.05, d = 0.18). Significantly more load-absorption work was performed during the CK (655 ± 276 J) compared to the PCK (288 ± 109 J; d = 1.75, p 0.05). Additionally, more load-absorption work was performed during the CPK compared to the PCK (d = 1.90, p = 0.032). Inclusion of the catch phase during the CK does not provide any additional stimulus in terms of mean force or work during the load-absorption phase compared to the CPK, while the CPK may be beneficial in training rapid force absorption due to high force and a short duration

    Comparing the Acute Effects of Intermittent and Continuous Whole-Body Vibration Exposure on Neuromuscular and Functional Measures in Sarcopenia and Nonsarcopenic Elderly Women

    Get PDF
    This investigation examined the acute effects of continuous whole-body vibration (CWBV) and intermittent whole-body vibration (IWBV) on neuromuscular and functional measures in women with sarcopenia and nonsarcopenic women. Continuous whole-body vibration was one 6-minute exposure, while IWBV consisted of six 60-second exposures to rest intervals (30 Hz, 2-4 mm amplitude). Factorial analyses revealed group × exposure × time interactions for jump height (JH; F = 10.8, P = .002), grip strength (GS; F = 15.5, P < .001), timed up and go test (F = 11.7, P = .002), and sit and reach test (S&R; F = 9.7, P = .004). Both JH and GS significantly improved post-WBV in women with sarcopenia (P < .001), with post-IWBV significantly greater (P < .001) than post-CWBV. Timed up and go test and S&R significantly improved post-IWBV in both the groups (P < .001) with post-IWBV significantly better than post-CWBV (P < .001). Bench press power at 20% one repetition maximum (1RM) revealed an exposure × time interaction (F = 4.6, P = .04) illuminating that IWBV significantly improved muscular power (P < .001). Bench press power at 40% 1RM revealed group × exposure (F = 6.4, P = .016) and exposure × time interactions (F = 5.8, P = .022). Individuals with sarcopenia significantly increased power output (P < .001) post-IWBV which was significantly greater than post-CWBV (P = .037). Bench press power at 60% 1RM revealed an exposure × time interaction (F = 8.6, P = .006), indicating that power was significantly improved post-IWBV (P = .027) and decreased post-CWBV. Berg Balance scale revealed a time main effect (F = 6.64, P = .015), and pain discomfort was significantly lower post-IWBV. These data indicate IWBV may provide a more efficacious exposure pattern in older women when compared to CWBV.The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Article processing charges funded in part by University of Oklahoma Libraries.YesTwo expert reviewers using single-blind process (reviewers' names and information is withheld from the authors). Established Ethics Policy with regards to who can review someone's work. The authors may nominate reviewers but the Editorial Board makes the final decision

    A numerical method for predicting the deformation of crazed laminated windows under blast loading

    Get PDF
    The design of laminated glazing for blast resistance is significantly complicated by the post-crack behaviour of glass layers. In this research, a novel numerical method based on a semi-analytical energy model is proposed for the post-crack behaviour of crazed panes. To achieve this, the non-homogenous glass cracks patterns observed in literature experimental and analytical work was taken into consideration. It was assumed that, after the glass crazing, further deformations would occur in the cracked edge areas, whilst the central window surface would remain largely undeformed. Therefore, different internal work expressions were formulated for each zone and were then combined in the overall model. The resulting differential equation was then solved numerically. The results obtained were compared with data from four experimental full-scale blast tests for validation. Three of these blast tests (Tests 1–3) were presented previously (Hooper et al., 2012) on 1.5 × 1.2 m laminated glazing samples made up with two 3 mm glass layers and a central 1.52 mm PVB membrane, using a 15 and 30 kg charge masses (TNT equivalent) at 13–16 m stand-off. The fourth blast test (Test 4) was conducted on a larger 3.6 × 2.0 m pane of 13.52 mm thickness, using a 100 kg charge mass (TNT equivalent) at a 17 m stand-off. All blast tests employed the Digital Image Correlation (DIC) technique to obtain 3D out-of-plane deflections and strains.The proposed analytical method reproduced the experimental deflection profiles, with the best estimates obtained for the more severe loading cases. Reaction forces were also compared with experimental estimates. The predictive ability of the proposed method could permit more accurate designs to be produced rapidly, improving structures resistance to such loadings
    corecore