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To clarify the characteristics of vertical drop jump (VDJ) for screening athletes at high risk of ACL injury by comparing the kinematic, kinetic and electromyographic variables of different VDJ.Thirty male soccer players were recruited to measure parameters of knee kinematics, kinetics, and surface electromyograph during VDJ in four kinds of movements measured (the distance between the take-off feet is 5 cm or 30 cm, and the distance between the landing feet is 5 cm or 30 cm) using the Vicon motion capture system, Kistler3-D dynamometer, and Noraxon surface electromyograph test system.The peak knee abduction moment was significantly greater for landing feet distance of 30 cm compared to landing feet distance of 5 cm, regardless of whether the distance between take-off feet was 5 cm (0.58 vs. 0.44) or 30 cm (0.61 vs. 0.40); regardless of whether the distance between landing feet was 5 cm (22.78 vs. 20.45) or 30 cm (24.32 vs. 21.87), the peak vertical Ground Reaction Force was significantly increased for the take-off feet distance was 5 cm compared to take-off feet of 30 cm.In the test of VDJ, athletes will adopt different landing strategies for different movement instructions, and the VDJ with the distance of 5 cm between the take-off feet and the distance of 30 cm between the landing feet may be the better maneuver to screen for risk of ACL injury.

Substrate plate heating is one of the methodology followed during the selective laser melting (SLM) process, to reduce the cooling rate of the process, to reduce the internal stresses in the SLM-fabricated material, to reduce the cracking tendency in some alloys. However, employing substrate plate heating with larger samples may introduce anisotropy and inhomogeneity in both microstructure and properties. To study this effect, Al-12Si samples were fabricated using the SLM process. The samples were produced with (473 K and 673 K) and without substrate plate heating. The sample was also subjected to external treatment at 473 K and 673 K to compare the microstructural effects with the substrate plate-heated samples. The microstructural investigation was carried out using optical and scanning electron microscopy and the structural characterization using X-ray diffraction. The mechanical properties of the samples were tested using room temperature tensile test and hardness maps. The results suggest that the samples fabricated using substrate plate heating lead to anisotropy along the length scale, which is not desirable.

The high-entropy alloy coatings reinforced with nano oxides were synthesized by the atmospheric plasma spraying (APS). The crystal structure, microstructure, surface morphology, hardness and wear resistance properties of the CoCrFeNiAl and CoCrFeNiMo high-entropy alloy coatings are investigated. For CoCrFeNiAl high entropy coating (HEC) not only has high hardness (573 ± 19 Hv0.1) but also has good wear resistance [The coefficients of friction (COF) is 0.49 ± 0.04]. The transition of the wear mechanism obviously appears between the two HECs. The influences of the structure, composition and hardness on the tribological behavior of high-entropy alloy coatings were discussed in details.

Six isoproteic diets were designated to evaluate the effects of dietary lipid levels (from 70 to 270 g/kg) on the growth performance, feed utilization, digestive tract enzyme activity and lipid deposition of juvenile Brachymystax lenok (average initial weight 0.54 ± 0.04 g). Each diet was fed to triplicate tanks (30 fish per tank) in an indoor closed recirculating system for 9 weeks. Final body weight and weight gain were highest in fish fed 190 g/kg diet and lowest in fish fed the 70 g/kg diet. Specific growth rate of fish fed with 190 g/kg diet was significantly higher than those fed with 70 and 270 g/kg diets (p

An Al0.1CoCrFeNi high-entropy alloy (HEA) with a face-centered cubic structure in the as-cast and the recrystallized states is investigated. The mean grain size of the as-cast HEA is 14 times larger than that of the recrystallized HEA. The tension tests reveal that deformation twinning is the main mechanism dominating the plastic deformation of two HEAs. With a decrease in the grain size, twin spacing increases, and twin thickness decreases, which results in a low twinning activity. The twinning activity of the recrystallized HEA is strongly inhibited by grain refinement, which degrades the promotion of twinning on the strain-hardening ability and the tensile ductility.

In the present study, a central composite rotatable design was used to optimise a microencapsulation process enclosing methionine with gelatine and sodium alginate by spray-drying. The results showed that the highest yield (92·2%) and efficiency (86·7%) of methionine microencapsulation were obtained, when the gelatine solution (40 g L−1)/sodium alginate solution (20 g L−1) ratio was 1 : 1, the methionine content was 15% and the feed speed was 35 mL min−1. In addition, the spray-dried microcapsules had a regular spherical shape and the crystalline methionine particles were enclosed by a wall system consisting of gelatine and sodium alginate. In vitro release study demonstrated that microcapsules could regulate methionine release and stimulate synchronous absorption of other amino acids to synthesise proteins. These observations suggest that methionine microencapsulation can be used to enhance the utilisation of amino acids and improve the application of methionine in aquaculture feed industry.

On 6 March 2015, Dawn arrived at Ceres to find a dark, desiccated surface punctuated by small, bright areas. Parts of Ceres’ surface are heavily cratered, but the largest expected craters are absent. Ceres appears gravitationally relaxed at only the longest wavelengths, implying a mechanically strong lithosphere with a weaker deep interior. Ceres’ dry exterior displays hydroxylated silicates, including ammoniated clays of endogenous origin. The possibility of abundant volatiles at depth is supported by geomorphologic features such as flat crater floors with pits, lobate flows of materials, and a singular mountain that appears to be an extrusive cryovolcanic dome. On one occasion, Ceres temporarily interacted with the solar wind, producing a bow shock accelerating electrons to energies of tens of kilovolts.

During the last thirty years, the Boulby Potash Mine has replaced the concrete shaft linings in sections of both shafts on two occasions following progressive deterioration. A third replacement lining is now under construction in the man shaft. This paper reports the results of two-dimensional (2D) and three-dimensional (3D) numerical modelling of the shaft linings and their surrounding strata. The numerical modelling, using FLAC2D and FLAC3D has considered the detrimental effect to lining stability of a weak rock zone surrounding the shafts at depth. The 3D modelling work has also taken into account the formation of an inset and roadway leading from the shaft. This research aimed to identify the failure mechanisms of the shaft linings in the affected zone and their causes. The research also supplied reference data to allow the prediction of stress and deformation conditions in the newly designed third shaft relining system.

This study examines the tail disconnection event on April 20, 2007 on comet 2P/Encke, caused by a coronal mass ejection (CME) at a heliocentric distance of 0.34 AU. During their interaction, both the CME and the comet are visible with high temporal and spatial resolution by the STEREO-A spacecraft. Previously, only current sheets or shocks have been accepted as possible reasons for comet tail disconnections, so it is puzzling that the CME caused this event. The MHD simulation presented in this work reproduces the interaction process and demonstrates how the CME triggered a tail disconnection in the April 20 event. It is found that the CME disturbs the comet with a combination of a $180^\circ$ sudden rotation of the interplanetary magnetic field (IMF), followed by a $90^\circ$ gradual rotation. Such an interpretation applies our understanding of solar wind-comet interactions to determine the \textit{in situ} IMF orientation of the CME encountering Encke.

The plasma environment of comet 67P/Churyumov-Gerasimenko, the Rosetta mission target comet, is explored over a range of heliocentric distances throughout the mission: 3.25 AU (Rosetta instruments on), 2.7 AU (Lander down), 2.0 AU, and 1.3 AU (perihelion). Because of the large range of gas production rates, we have used both a fluid-based magnetohydrodynamic (MHD) model as well as a semi-kinetic hybrid particle model to study the plasma distribution. We describe the variation in plasma environs over the mission as well as the differences between the two modeling approaches under different conditions. In addition, we present results from a field aligned, two-stream transport electron model of the suprathermal electron flux when the comet is near perihelion.

Slip avalanches, similar to discrete earthquake events, of Zr-, Co-, and Ce-based metallic glasses during nanoscratching were investigated. Differing from the conventional continuum approach, mean-field theory, which is an inherently-discrete model, was applied to analytically compute intermittent slip avalanches. Mean-field theory was first connected with the potential energy barrier and concentration of free volume in order to study the stick-slip behavior. The results suggest that the motion behavior of free volume affects the critical slip avalanche size.

This study investigated the biochemical composition of ovarian fluid and its effect on the fertilization capacity of turbot Scophthalmus maximus during the spawning season. The fertilization rate and pH of ovarian fluid varied throughout the spawning season, with the highest values recorded at the mid-season. Positive correlations were found between the fertilization rate and the ovarian fluid pH. The composition of major inorganic ions (Na(+) , K(+) , Ca(2+) and Cl(-) ) showed no significant changes during the spawning season. Alkaline phosphatase (AKP) activity was significantly higher during mid-season than other seasons. The lowest levels of protein, acid phosphatase (ACP) and aspartate aminotransferase (AAT) were in the ovarian fluid released at the mid-season. Moreover, significant relationships were observed between the fertilization rate and the levels of protein, ACP, AKP and AAT. These observations suggest that the biochemical profile of ovarian fluid affects the insemination microenvironment as well as the fertilization capacity of S. maximus eggs. Determination of such profiles may prove to be a useful strategy to improve S. maximus breeding techniques.

Through ejection from its southern hemisphere, Enceladus is a dominant source of neutral gas and dust in Saturn’s inner magnetosphere. The interaction of the corotating plasma with the gas and dust modifies the plasma environment around Enceladus. We use 3‐D hybrid (kinetic ions, fluid electrons) simulations to examine the effects of gas and dust on the nature of the interaction region and use Cassini observations to constrain their properties.