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The aim of the study was to explore the service roundtechnical-tactical performance indicators of three phases discriminating thematch result and the two match forms. The statistics of 72 professional men’ssingles matches of the 2018 international competitions were collected. Achi-square test was used to assess the relationship between match form, matchoutcome and service round result. Afterwards, a two-way ANOVA was performed toevaluate the effect of match form (SHM: match between players of the same handedness and OHM: match between players of the opposite handedness) and match result on three evaluation indices of thirteen technical-tactical indicators. The resultsdisplayed that: (1) there was a weak relationship between the service roundoutcome and match form for both the winning and losing players (p

The effect of ionized gas on the propagation of radio signals is known as plasma lensing. Unlike gravitational lensing, plasma lensing causes both magnification and strong de-magnification effects to background sources. We study the cross section of plasma lensing for two density profiles, the Gaussian and power-law models. In general, the cross section increases with the density gradient. Radio sources can be used to measure the free electron density along the line of sight. However, plasma lensing de-magnification causes an underestimate of the electron density. Such a bias increases with the electron density, and can be up to $\sim 15\%$ in the high density region. There is a large probability that high density clumps will be missed due to this bias. The magnification of plasma lensing can also change the luminosity function of the background sources. The number density of sources on both the high and low luminosity ends can be overestimated due to this biasing effect., MNRAS accepted, comments welcome

The aim of the current study was twofold: (a) to construct an Interactive Three-Phase Structure for table tennis performance analysis and (b) to apply the proposed structure to the performance analysis of elite men’s singles matches. The current structure makes improvements over the former ones in the following aspects: more comprehensive performance variables consisting of bilateral actions covering the whole rally competing process, a better phase division method fitting to the real match situation and more focused analysis achieved by the designed critical phase. The analysis of 56 elite men’s singles matches (5507 rallies) was conducted using the proposed structure. The results demonstrated that performance variables of the rally competing process ceasing in Phase 2 (initial attack and counterattack phase) were decisive for the rally outcome of elite men’s singles matches. The proposed structure provides practitioners with a better model to enhance the effectiveness of table tennis performance analysis.

Background: Sepsis, as one of the severe diseases, is frequently observed in critically ill patients, especially concurrent with diabetes. Whether admission blood glucose is associated with the prognosis, and outcome of septic patients is still debatable.Methods: We retrospectively reviewed and analyzed the demographic characteristics of septic patients in the Medical Information Mart for Intensive Care III (MIMIC III, version 1.4) between June 2001 and October 2012. The Chi-square and Fisher's exact tests were used for the comparison of qualitative variables among septic patients with different glucose levels and the 30-day mortality in septic patients with diabetes or not. Univariate and stepwise multivariate Cox regression analyses were used to determine the risk factors for 30-day mortality. Kaplan-Meier analysis was conducted to reveal the different 30-day survival probabilities in each subgroup.Results: A total of 2,948 septic patients (910 cases with diabetes, 2,038 cases without diabetes) were ultimately included in the study. The 30-day mortality was 32.4% (956/2,948 cases) in the overall population without any difference among diabetic and non-diabetic septic patients (p = 1.000). Admission blood glucose levels p < 0.001). After adjusting for confounders, age >65 years (HR = 1.53, p = 0.001), the Sequential Organ Failure Assessment (SOFA) score >5 (HR = 2.26, p < 0.001), lactic acid >2 mmol/L (Lac, HR = 1.35, p = 0.024), and platelet abnormality (300 k/ul: HR = 1.36, p < 0.001) were the independent risk factors for 30-day mortality in septic patients with diabetes. In non-diabetes population, age >65 years (HR = 1.53, p < 0.001), non-White or non-Black patients (HR = 1.30, p = 0.004), SOFA score >5 (HR = 1.56, p < 0.001), blood glucose p = 0.003), anion gap (AG) >2 mmol/L (HR = 1.60, p < 0.001), Lac (HR = 1.61, p < 0.001), urea nitrogen >21 mg/dl (HR = 1.45, p = 0.001), alanine aminotransferase (ALT, HR = 1.31, p = 0.009), total bilirubin >1.2 mg/dl (HR = 1.20, p = 0.033), and low hemoglobin (HR = 1.34, p = 0.001) were the independent risk factors for 30-day mortality.Conclusions: Our results indicate admission blood glucose, especially in terms of

The propagation characteristics of high-average-power tube laser from a hemisphere turret on an airborne platform is studied theoretically. Based on the theoretical model for the four-dimensional propagation model of tube laser beams, the influences of aero-optical effect, atmosphere turbulence and thermal blooming effect on the propagation characteristics of the tube laser are simulated and analyzed. The results show that the aero-optical effect contributes dominantly to the degradation of the tube laser under the conditions of high speed and high altitude and further brings about severe beam spreading and centroid shift. Owing to the low air density at high altitude and high heat exchange efficiency at high speed, the atmosphere turbulence and thermal blooming effect are extremely weak. This result implies that the areo-optical effect should be paid more attention for the realization of long-distance propagation of tube lasers on high altitude flights.

Generation of vortex beams with tunable topological charges is of significant importance in a wide range of applications. A novel method is proposed to generate such donut-like Laguerre–Gaussian (LG) vortex beam by the solid-state zigzag tube lasers. The LG TEM 0 l mode with tunable beam order l can be directly obtained from the tube laser oscillator by simply adjusting a mode selector consisting of a pair of complementary cone lenses and an amplitude mask. Subsequently, the LG beam with topological charge of +l or − l is constructed by the coherent superposition of the LG TEM 0 l modes with appropriate phase difference. This method enables the generation of LG beams with high mode purity, and the value and sign of the topological charges of the generated LG beam can be individually and flexibly controlled by appropriately adjusting the mode selector and the phase difference of LG TEM 0 l modes, respectively. The physical model of the method was established, and the feasibility for generating topological-charge-tunable LG 0 l beams was demonstrated by numerical simulation. All the generated LG 0 l beams possess high purities and the highest purity reaches to 99.3% in the simulation. This method provides an alternative approach to generate topological-charge-tunable LG beam in solid-state lasers.

Compared to zig-zag solid-state slab lasers, zig-zag solid-state tube lasers (SSZTLs) exhibit significant potential in beam quality improvement and output power enhancement. However, the progress of SSZTLs still faces enormous challenges due to the lack of effective control of beam quality. We first developed a comprehensive model for analyzing the output beam quality of zig-zag tube lasers by taking both the fabrication and alignment errors and thermal effects into consideration. The primary factors degrading the beam quality and thermal stability of the SSZTLs were analyzed in detail, and a self-correction method based on the complementary optical path was further proposed and analyzed theoretically to effectively improve the beam quality and thermal stability of the SSZTLs. The results show that this method can not only effectively correct the off-axis aberrations but also mitigate the depolarization loss that arises from the thermal instability of the SSZTLs. This work can provide a reference in the beam control and applications of SSZTLs.