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Mehdi Kargarfard Eddie T.C. Lam Ardalan Shariat Ina Shaw Brandon S. Shaw Shamsul B.M. Tamrin 《Journal of sports sciences》2016,34(10):959-965
It is believed that sport massage after intensive exercise might improve power and perceptual recovery in athletes. However, few studies have been done in this area. This study aimed to examine the effect of massage on the performance of bodybuilders. Thirty experienced male bodybuilders were randomly assigned to either a massage group (n = 15) or a control group (n = 15). Both groups performed five repetition sets at 75–77% of 1RM of knee extensor and flexor muscle groups. The massage group then received a 30-min massage after the exercise protocol while the control group maintained their normal passive recovery. Criteria under investigation included: plasma creatine kinase (CK) level, agility test, vertical jump test, isometric torque test, and perception of soreness. All variables were measured over 6 time periods: baseline, immediately after the DOMS inducing protocol, right after the massage, and 24, 48, and 72 h after the massage. Both groups showed significant (P < .001) decreases in jumping, agility performance, and isometric torque, but significant (P < .001) increases in CK and muscle soreness levels. The massage group in general demonstrated a better recovery rate. As such, a post-exercise massage session can improve the exercise performance and recovery rate in male bodybuilders after intensive exercise. 相似文献
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Modeling of D-STATCOM in distribution systems load flow 总被引：1，自引：0，他引：1
HOSSEINI Mehdi SHAYANFAR Heidar Ali FOTUHI-FIRUZABAD Mahmud 《浙江大学学报(A卷英文版)》2007,8(10):1532-1542
This paper presents modeling of Distribution STATCOM (D-STATCOM) in load flow calculations for the steady- state voltage compensation. An accurate model for D-STATCOM is derived to use in load flow calculations. The rating of this device as well as the direction of required reactive power injection for voltage compensation in the desired value (1 p.u.) is de- rived and discussed analytically and mathematically by the phasor diagram method. Furthermore, an efficient method for node and line identification used in load flow calculations is presented. The validity of the proposed model is examined by using two standard distribution systems consisting of 33 and 69 nodes, respectively. The best location of D-STATCOM for under voltage problem mitigation approach in the distribution networks is determined. The results validate the proposed model for D- STATCOM in large distribution systems. 相似文献
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Mehdi Ghadami 《国际体育史杂志》2015,32(8):986-1000
One of the key features of the Olympic movement is its universalistic appeal, particularly in the sense that it has sought to establish itself as a platform for universal interaction and promotion of universal values. In this paper, we consider the nature, feasibility, and implications of the IOC's promotion of its universalist position in terms of the ethical standards it promotes in relation to universal principles of good governance. A major problem in this respect is the culturally diverse set of constituencies that are incorporated within the Olympic movement, such that the imposition of ‘one size fits all’ policies may be impractical and in many instances undesirable. The authors of this paper therefore argue that although universal agreement is often impractical, general agreement may often be established. The paper therefore presents an approach to balancing centrally promoted principles of good governance with local preferences in terms of the weighting to be given to particular values within the operationalization of good governance. This approach, based on the Analytic Hierarchy Process technique, developed by Thomas Saaty and widely employed in decision-making with regard to evaluating and weighting alternatives, is introduced here in the context of the evaluation of National Sport Federations in Iran. The paper highlights ways in which this technique allows for the expression of local priorities within the general framework of good governance principles in ways which satisfied both global and local priorities. In effect, it is a practical example of what Robertson has termed glocalization. The paper concludes by applying this framework to an evaluation of the National Federation (NF) of Football in Iran as an example of how this technique will be used for the purposes of ranking NFs in terms of performance with respect to elements of good governance which will inform both self-assessment by the NF and the decision-making process for allocation of funds by government to NFs in Iran in the future. 相似文献
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A multidisciplinary approach is implemented to model and analyse the performance of Olympic rowing boats. A reduced-order model that couples rowers motions with the hull, oars and hydrodynamic and hydrostatic forces is detailed. This model is complemented with a sensitivity analysis carried out by means of a non-intrusive polynomial chaos expansion. Sensitivity analysis results for two different boat classes, namely, a lightweight single scull and a coxless four are presented and discussed. This analysis contrasts, for both classes, the effects of varying forces exerted by the rowers, weights of rowers and cadence of motions on the boat performance. 相似文献
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Mehdi Kordi Chris Fullerton Louis Passfield Len Parker Simpson 《European Journal of Sport Science》2019,19(2):192-198
Body position is known to alter power production and affect cycling performance. The aim of this study was to compare mechanical power output in two riding positions, and to calculate the effects on critical power (CP) and W′ estimates. Seven trained cyclists completed three peak power output efforts and three fixed-duration trial (3-, 5- and 12-min) riding with their hands on the brake lever hoods (BLH), or in a time trial position (TTP). A repeated-measures analysis of variance showed that mean power output during the 5-min trial was significantly different between BLH and TTP positions, resulting in a significantly lower estimate of CP, but not W′, for the TTP trial. In addition, TTP decreased the performance during each trial and increased the percentage difference between BLH and TTP with greater trial duration. There were no differences in pedal cadence or heart rate during the 3-min trial; however, TTP results for the 12-min trial showed a significant fall in pedal cadence and a significant rise in heart rate. The findings suggest that cycling position affects power output and influences consequent CP values. Therefore, cyclists and coaches should consider the cycling position used when calculating CP. 相似文献
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Mehdi Chowdhury 《Assessment & Evaluation in Higher Education》2020,45(5):643-650
AbstractThe method of normalisation combined with peer ratings is utilised to provide the solution to the biased rating problem of mapping group work marks to individual marks. We critically evaluate the method of normalisation following the findings of an article which argued against the use of self and/or peer rating mechanism. We demonstrate that the findings of that article also hold for the method of normalisation as the influence of human behavioural factors are not accommodated in the designs. Additionally, we argue that the method (and its variants) is rather complicated, where all possible contingencies are not pre-specified. It makes the arrangement between tutors and students in conducting peer assessments incomplete and unverifiable by a third party. 相似文献
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Intracellular drug delivery by rapid squeezing is one of the most recent and simple cell membrane disruption-mediated drug encapsulation approaches. In this method, cell membranes are perforated in a microfluidic setup due to rapid cell deformation during squeezing through constricted channels. While squeezing-based drug loading has been successful in loading drug molecules into various cell types, such as immune cells, cancer cells, and other primary cells, there is so far no comprehensive understanding of the pore opening mechanism on the cell membrane and the systematic analysis on how different channel geometries and squeezing speed influence drug loading. This article aims to develop a three-dimensional computational model to study the intracellular delivery for compound cells squeezing through microfluidic channels. The Lattice Boltzmann method, as the flow solver, integrated with a spring-connected network via frictional coupling, is employed to capture compound capsule dynamics over fast squeezing. The pore size is proportional to the local areal strain of triangular patches on the compound cell through mathematical correlations derived from molecular dynamics and coarse-grained molecular dynamics simulations. We quantify the drug concentration inside the cell cytoplasm by introducing a new mathematical model for passive diffusion after squeezing. Compared to the existing models, the proposed model does not have any empirical parameters that depend on operating conditions and device geometry. Since the compound cell model is new, it is validated by simulating a nucleated cell under a simple shear flow at different capillary numbers and comparing the results with other numerical models reported in literature. The cell deformation during squeezing is also compared with the pattern found from our compound cell squeezing experiment. Afterward, compound cell squeezing is modeled for different cell squeezing velocities, constriction lengths, and constriction widths. We reported the instantaneous cell center velocity, variations of axial and vertical cell dimensions, cell porosity, and normalized drug concentration to shed light on the underlying physics in fast squeezing-based drug delivery. Consistent with experimental findings in the literature, the numerical results confirm that constriction width reduction, constriction length enlargement, and average cell velocity promote intracellular drug delivery. The results show that the existence of the nucleus increases cell porosity and loaded drug concentration after squeezing. Given geometrical parameters and cell average velocity, the maximum porosity is achieved at three different locations: constriction entrance, constriction middle part, and outside the constriction. Our numerical results provide reasonable justifications for experimental findings on the influences of constriction geometry and cell velocity on the performance of cell-squeezing delivery. We expect this model can help design and optimize squeezing-based cargo delivery. 相似文献
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Mehdi Dadkhah Glenn Borchardt Mohammad Lagzian Giorgio Bianciardi 《Publishing Research Quarterly》2017,33(2):183-187
The current status of academic publishing is worrying. Cybercriminals are now targeting academic audiences, making it necessary to inform both editors and authors about such issues. The latest involves bogus impact factors, which are challenging scholarly publishing. Legitimate impact factors are used by authors and editors to get a general idea of the audience, if any, for a particular piece or journal. The bogus metrics only add confusion in support of the cybercrimes of their initiators. In this paper, we discuss bogus impact factors, victim countries, and try to clarify the phenomena for both authors and editors. 相似文献