To assess the responses to taper in endurance athletes using meta-analysis.
Systematic searches were conducted in China National Knowledge Infrastructure, PubMed, Web of Science, SPORTDiscus, and ...EMBASE databases. Standardized mean difference (SMD) and 95% confidence interval (CI) of outcome measures were calculated as effect sizes.
14 studies were included in this meta-analysis. Significant improvements were found between pre- and post-tapering in time-trial (TT) performance (SMD = -0.45; P < 0.05) and time to exhaustion (TTE) performance (SMD = 1.28; P < 0.05). However, There were no improvements in maximal oxygen consumption (Formula: see text) and economy of movement (EM) (P > 0.05) between pre- and post-tapering. Further subgroup analysis showed that tapering combined with pre-taper overload training had a more significant effect on TT performance than conventional tapering (P < 0.05). A tapering strategy that reduced training volume by 41-60%, maintained training intensity and frequency, lasted ≤7 days, 8-14 days, or 15-21 days, used a progressive or step taper could significantly improve TT performance (P < 0.05).
The tapering applied in conjunction with pre-taper overload training seems to be more conducive to maximize performance gains. Current evidence suggests that a ≤21-day taper, in which training volume is progressively reduced by 41-60% without changing training intensity or frequency, is an effective tapering strategy.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
For an effective NURBS interpolator, generating the smooth feedrate profile and minimizing the feedrate fluctuation are two main tasks, which have a great influence on the machining quality. In this ...paper, a NURBS interpolator is proposed to solve the problem with offline-online two stages, which contain curving splitting, feedrate scheduling, and real-time interpolation modules. At first, in offline module, the limited feedrate of the curve is calculated with consideration of geometric characteristics and dynamic constraints, and the curve is split into several segments according to the key regions. Thus the necessary information is stored. Then the feedrate scheduling algorithm is applied with constant feedrate scheduling method at each segment, where tangential acceleration and jerk are taken into consideration to generate an adaptive smooth S-type feedrate profile. Moreover, in real-time interpolation module, an average feedrate calculation method is proposed to determine the sampling step size. And to minimize the feedrate fluctuation, a double interpolation algorithm based on the cosine theorem is presented, which use the second-order Taylor’s expansion method two times in one interpolation period. Finally, simulations and experiments are conducted to verify the performance of the proposed interpolator.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Colorectal carcinoma (CRC) is one of the most common cancers globally. It is essential to identify a prognostic predictor for CRC. Pentraxin 3 (PTX3) is a glycoprotein that is secreted by a variety ...of human cells. It plays an important role in inflammation and immune regulation. Increasing evidence reveals that elevated PTX3 expression is related to poor prognosis in various cancers. The aim of the study was to determine the usefulness of plasma PTX3 level as a prognostic predictor in CRC. Total 184 CRC patients and 216 controls were included. Plasma levels of PTX3 were determined using Enzyme-linked immunosorbent assays. On admission, plasma PTX3 levels in CRC patients were higher than those in controls (11.8 ± 2.5 ng/ml vs. 3.1 ± 0.9 ng/ml, P < 0.001). After resection, plasma PTX3 levels in patients were decreased (6.0 ± 1.4 ng/ml, P = 0.007), and were elevated at the time of relapse (10.8 ± 2.8 ng/ml, P < 0.001). During the 60-month follow-up period, 108 patients suffered from relapse. Plasma PTX3 levels of ≥ 12 ng/ml on admission were associated with relapse (OR: 3.11, 95% CI: 1.74 ~ 6.29), and tumor-free survival rate in those patients with plasma PTX3 levels of ≥ 12 ng/ml was lower than that in other patients (P = 0.001). Furthermore, plasma PTX3 levels on admission showed positive linear correlations with plasma complement 3, 4 and 5b9 levels (P < 0.001, P < 0.001, P < 0.001). Therefore, we propose that PTX3 is an independent prognostic indicator in CRC.
The instantaneous uncut chip thickness is an important parameter in the study of milling force model. By analyzing the real tooth trajectory in milling process, accurate instantaneous uncut chip ...thickness can be obtained to solve the complex transcendental equation. Traditional chip thickness models always simplify the tooth trajectory to get approximate solution. A new instantaneous uncut chip thickness model is proposed in this paper. Based on real tooth trajectory of general end milling cutter, a Taylor's series is used to approximate the involved infinitesimal variable in the transcendental equation, which results in an explicit expression for practical application of the uncut chip thickness with higher accuracy compared to the traditional model.
In this paper, the effect of deposition velocity on bonding degree is studied in the aspects of experiment and theory. The experimental results show that the bonding quality of the adjacent filaments ...is weakened with increasing of deposition velocity. In addition, on the premise of guaranteeing every point in the building process to remain at the optimal temperature, the quantitative relationships between interval and filled area, deposition velocity are investigated by using the technique of deactivate and reactivate element of finite element. On the base of the quantitative relationships, the variable deposition velocity printing method is proposed for the first time. Namely, to reap the best bonding quality of filaments the time of completing one layer can be determined according to the filled area, and then, the optimal deposition velocity can be obtained according to the quantitative relationship between the interval and the deposition velocity. Printing the model at this speed can obtain the part with the best bonding quality between adjacent layers.
Abstract A number of in vitro, invasive in vivo, and non-invasive marker based multi-segment foot models (MSFMs) have reported significant motion in the articulations distal to the calcaneus during ...gait. Few studies, however, have applied a MSFM to the investigation of the effect of foot posture on gait kinematics. Differences in stance phase kinematics between participants with low-mobile (LMF) ( n = 11) versus “typical” (TYPF) ( n = 11) foot postures were investigated using a multi-segment medial foot model. Three-dimensional position and stance phase excursions of four functional articulations (rearfoot complex RC, calcaneonavicular complex CNC, medial forefoot, first metatarsophalangeal complex) were quantified using an eight optical camera motion analysis system (Vicon Motus, Vicon Motions Systems, Centennial, CO) and a custom written software program (Matlab 7.0.1, The MathWorks, Natick, MA), respectively. Excursions during four subphases of stance phase (loading response, midstance, terminal stance, pre-swing) at each of the functional articulations were compared using multivariate analyses of variance ( α ≤ 0.05). Results revealed significantly decreased LMF group CNC abduction excursion ( p = 0.047) during midstance. During pre-swing, LMF group RC inversion excursion was significantly increased ( p = 0.032) and eversion excursion was significantly decreased ( p = 0.003) compared to the TYPF group. When these differences are considered in conjunction with the kinematic patterns of other foot/leg segments and functional articulations, the changes may suggest dysfunction of normal leg-calcaneus coupling and the constrained tarsal mechanism associated with low-mobile foot postures.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In this paper, the mathematical model of "S" - shaped cutting-edge curve is optimized, and the position and orientation of the grinding wheel of the first and second flank of the ball end milling ...cutter are calculated, The correctness of the algorithm is verified by VERICUT simulation.
Stator current signal of driving motor can be easily measured. Using it in the gearbox fault diagnosis system is inexpensive and suitable for remote monitoring. According to the application of the ...Motor Current Signal Analysis in machinery fault detection, we present a new gearbox fault diagnosis system. In modern signal processing technology, Stochastic Resonance theory is widely used to improve SNR (signal to noise ratio). Dynamic time warping algorithm is a simple and efficient way of the pattern identified. Combine the Stochastic Resonance theory and dynamic time warping algorithm as the basic theory of fault diagnosis. To realize the development of fault diagnosis software, we use the mixed-programming of MATLAB algorithms library and VC++.
Dynamic time warping used in speech recognition widely was migrated to fault feature extraction and diagnosis in time domain. Integration of phase compensation, slope weighted, derivative, sliding ...window connection, fast dynamic time planning method is applied to dynamic time warping method. And a new method of time-domain signal feature extraction and fault diagnostic based on improved dynamic time warping method of mechanical and electrical equipment was proposed. Identification and localization of fault signal characteristics may be done by improving dynamic time warping method to obtain a residual signal sequences with fault characterized sidebands and selecting the statistical characteristic parameters such as peak, RMS, kurtosis spectrum to complete identification and localization of fault signal characteristics. New time-domain fault trend prediction method of mechanical and electrical equipment was established based on new statistical parameter Thikat. A new idea and target was provided for fault diagnosis of mechanical and electrical equipment.
Low temperature plasma, compared to liquid phase treatment, can effectively overcome the environment pollution, high energy loss and high cost as its high activity. The low temperature plasma, which ...is not only fairly friendly to the environment but also of less resource consumption, also can realize the cleaning, activating and grafting treatment for materials surface. Based on the numerical model of CRFHCP (Capacitive Radio Frequency Hollow Cathode Plasma) hollow cathode plasma discharge, the key point to affect plasma discharge was analyzed and the morphology of PP film before and after hollow cathode plasma discharge was analyzed. The results showed that the structure of plasma hollow cathode discharge can effectively improved the chemical behaviors of PP film.
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