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•Wood waste was applied as filler for PLA matrix.•Evaluated physical, mechanical and wear properties were fixed as selection criteria.•Increased wood waste resulted in higher modulus with decreased density.•Hybrid entropy - SAW approach was used for ranking analysis.•Optimum properties were obtained for 2.5 wt.% wood waste added composites.

Viscose and polypropylene fiber-based needlepunched nonwoven fabric mat reinforced epoxy composites with varying mass per unit area (200, 400 and 600g/m2) and varying fabric mat weight percentage (20, 30, and 40wt.%) were fabricated. The manufactured composites were characterized for physical (density, void content), mechanical (impact energy, flexural, tensile and inter-laminar shear strength) and erosive wear properties. The evaluated properties were considered as performance defining attributes (PDAs) for the assessment of the composites. The experimental results indicate that there was no single composite which satisfied all the selected PDAs. Therefore, the improved preference selection index (PSI) approach was proposed to select the best composite alternative which yielded optimized physico-mechanical and erosive wear properties by considering all the PDAs at a single time. It was found that the composite alternative containing 40wt.% of 600g/m2polypropylene fiber displayed the optimal physico-mechanical and erosive wear properties.

Running is one of the most accessible physical activities and long-distance running has attracted extensive attention in the past several years. While the incidence of running injuries, especially to the lower extremities, has increased. The objective of this study was to investigate the differences in ground reaction forces (GRF) and kinematic param between long-distance runners before and after long-distance running on treadmill (TM), asphalt road (AR), and plastic track (PT). Eight-camera Vicon motion analysis system was used to measure the hip, knee and ankle motion param of 10 healthy male subjects at a speed of 2.8 ± 0.2m/s. The hip, knee and ankle kinematics and the relationship of joint angles of lower limbs in the sagittal plane, coronal plane and transversal plane were analyzed. Ground reaction force (GRF) was collected using an AMTI force platform. The results showed that there were no significant differences in GRF and average loading rate (VALR). There was no significant difference in the range of motion (ROM) of ankle and hip after long-distance running on three surfaces compared to pre-test. Compared with stance-period of pre-test, the stance-period of AR and PT were significantly longer. Post hoc analyses exhibited the stance-period of AR and PT were longer than TM. In conclusion, runners can adjust different joints angles to maintain a similar GRF during long-distance running on different sports surfaces.

Novel friction composites materials using pineapple fiber as a sustainable alternative for automotive industry were developed by increasing its amount from 5−20wt.% in the step of 5 %. To compare the performance of pineapple fiber, friction composites with 5−10wt.% of Kevlar fiber were also manufactured. The results of physico-mechanical properties reveal that density, hardness and ash content decrease whereas water absorption, porosity and compressibility increase with the increased pineapple/Kevlar fiber contents. Further, the friction and fade performance were found to decrease whereas the recovery performance and wear was found to increase with increased pineapple fiber content. Among pineapple fiber reinforced composites, the best composite is the one having 5wt.% pineapple fibers that exhibits the highest performance in terms of coefficient of friction (0.548), lowest fade-% (36.31 %) along with the lowest specific wear rate (3.49×10−8cm3/N-m). Nonetheless, the results show that the 5wt.% Kevlar fiber based composite reveals good performance in terms of coefficient of friction (0.592) with slightly lower fade-% (35.98 %), recovery-% (107.43 %) and specific wear rate (3.46×10−8cm3/N-m) when comparing to 5wt.% pineapple fiber based composites. Finally, the possible wear mechanisms were discussed with the help of composites worn surface morphologies.

In this work, vinylester resin based and hybrid Kevlar-bagasse fiber reinforced homogeneous and graded composites were developed and evaluated for wear performance on a pin-on-disc machine. An orthogonal array (L16) was applied to examine the influence of four tribological control factors i.e. fiber content, normal load, sliding distance and sliding velocity. The experimental results indicate that normal load emerges as the most important factor affecting the wear rate of vinylester based graded and homogeneous composites with a contribution ratio of 36.33% and 32.09% respectively. Furthermore, composites worn surfaces were analyzed using scanning electron microscopy and the possible wear mechanism was studied.

Foot temperature can be affected by friction and contact pressure, in this study, we explored the specific changes of foot temperature under different friction conditions, running with socks versus no socks. The relationship between vertical loading force and foot temperature will also be investigated at the same time. Ten male recreational runners wore the same shoes and socks and were tested running 8km/h on a treadmill. The plantar temperature during running was recorded every 3 minutes for a total of 45 minutes. Post-run temperature change was recorded every 3 minutes for 12 minutes. The plantar pressure was recorded before running and at the first 15 minutes during running. The subjects with socks and no socks were tested on separate occasions. There were no significant differences found between the socks and no socks conditions. However, central metatarsal head, lateral metatarsal head, medial rearfoot and lateral rearfoot regions exist differences were reflected at the first 6minutes-12minutes of running. The foot temperature became more stable after 15minutes of running. Also, plantar pressure increased significantly in the hallux, other toes, first metatarsal head and central metatarsal regions. It also could conclude that lower initial temperature had a greater increase trend during the running start stage. When the ankle in plantarflexion stage, toe and forefoot regions showed a higher rise in temperature and also presented higher plantar pressure correspondingly.

To determine the influence of the unstable sole structure on foot kinematics and provide theoretical basis for further application.12 healthy female subjects walked through a 10-meter experimental channel with normal speed wearing experimental shoes and control shoes respectively at the gait laboratory. Differences between the groups in triplanar motion of the forefoot, rearfoot and hallux during walking were evaluated using a three-dimensional motion analysis system incorporating with Oxford Foot Model (OFM). Compare to contrast group, participants wearing experimental shoes demonstrated greater peak forefoot dorsiflexion, forefoot supination and longer halluces plantar flexion time in support phase. Additionally, participants with unstable sole structure also demonstrated smaller peak forefoot plantarflexion, rearfoot dorsiflexion and range of joint motion in sagittal plane and frontal plane.. The difference mainly appeared in sagittal and frontal plane. With a stimulation of unstable, it may lead to the reinforcement of different flexion between middle and two ends of the foot model. The greater forefoot supination is infered that the unstable element structure may affect the forefoot motion on the frontal plane and has a control effect to strephexopodia people. The stimulation also will reflexes reduce the range of rearfoot motion in sagittal and frontal planes to control the gravity center of the body and keep a steady state in the process of walking.

The purpose of this study was to evaluate the biomechanical performances, running stability of habitually barefoot (BR) and shod runners (SR) during barefoot jogging and running. Ten healthy male subjects, 5 habitually shod runners and 5 habitually barefoot runners, from two different ethnics participated in this study. Subjects performed jogging (2m/s) and running (4m/s) along a 10-m runway. Three-dimensional lower-limb kinematics, ground reaction force, center of pressure (COP) and contact time (CT), were collected during testing. During jogging and running, all participants adopted rear-foot strike pattern, SR had larger VALR. SR showed significantly larger lower-limb range of motion (ROM) in sagittal plane, significantly larger hip abduction and opposite knee ROM in frontal plane, as well as significantly larger ankle internal rotation in horizontal plane. All participants’ CT showed decreased trend with running speed up; and SR was significantly longer than BR; BR and SR in COP showed different trajectories, especially forefoot and rearfoot areas. Habitually barefoot and shod runner from different ethnics still exist significant differences in lower-extremity ROM; and different foot morphological of participants is an important influential factor for these variations.

The median frequency (MF) and mean power frequency (MPF) have been confirmed as reliable indicators of muscle fatigue during sustained contractions. The purpose of this study was to explore whether single-monitor arm could release muscle fatigue in neck-shoulder region while maintaining a prolonged seated posture viewing computer screen by measuring MF and MPF. Ten male healthy university students volunteered to participate in the test. Surface electromyography of splenius capitis (SC) and trapezius (TR) were recorded. Each subject performed normal text editing tasks or video watching activities for 120 minutes with different monitor arm positions (Fixed, moving downward and moving upward). Results showed that the MPF of SC and TR had significant decreased trend as monitor arm at fixed position. As monitor arm moving upward, the MF and MPF of both muscles decreased significantly with time and the MF showed the lowest decline rate during the entire testing process. No significant shift of MF and MPF were observed as monitor arm moving downward. Findings of this study may have important implications for people who use computer intensively to release neck-shoulder muscle fatigue.

The purpose of this study was to testing for difference in performance and injury risks between three different outsole configuration soccer boots on artificial turf. Fourteen experienced soccer players performed 45° cut test. They selected soccer boots with artificial ground design (AG), turf cleats boots (TF) and indoor boots (IN) randomly. A Vicon three dimension motion analysis system was used to capture kinematic data and Kistler force platform was used to record the ground reaction force. Novel Pedar-X insole plantar pressure measurement system was utilized to collect the plantar pressure synchronized. During 45° cut, artificial ground design (AG) showed significantly smaller peak knee flexion (p<0.001) and greater abduction angles (p<0.001) than indoor boots (IN). AG showed significantly greater vertical average loading rate (VALR) compared with TF (p=0.005) and IN (p=0.003). The results of plantar pressure found that AG showed the highest peak pressure and force-time integral in the heel (H) and medial forefoot (MFF). Artificial ground design (AG) and turf cleats (TF) may offer a performance benefit on artificial turf compared to IN. In summary, AG may enhance athletic performance on artificial turf, but also may undertake higher risks of non-contact injuries compared with TF and IN.

Volleyball players often land on a single leg following a spike shot because of a shift in the center of gravity. This landing is one of the high-risk actions for non-contact ACL injury. The purpose of this study was to compare and analyze the discrete and temporal kinematics and kinetics associated with functional valgus collapse during volleyball in player landing phases during a single-leg landing and double-leg landing following a spike shot. Kinematics and kinetics data were collected (captured by a Vicon motion system and AMTI force plate, processed by Visual-3D software) during the single-leg and double-leg landing phases in 13 semi-professional male volleyball players. The landing phase was defined as initial ground contact (0% landing phase) to maximum knee flexion (100% landing phase). Statistical Parametric Mapping (SPM) analysis revealed that single-leg landing depicted a significantly greater knee abduction angle and hip adduction moment than double-leg landing during the 0%–68% landing phase (single-leg: 7°–16°, double-leg: 0°–9°, p< 0.001) and 18%–22% (single-leg: 0.62–0.91 Nm/kg, double-leg: 0.08–0.19 Nm/kg, p= 0.0063) landing phase, respectively. The traditional discrete analysis revealed that single-leg landing depicted a significantly greater peak knee internal rotation moment (single-leg: 1.46 ± 0.38 Nm/kg, double-leg: 0.79 ± 0.19 Nm/kg, p= 0.006) and peak hip internal rotation moment (single-leg: −2.20 ± 0.54 Nm/kg, double-leg: −0.88 ± 0.30 Nm/kg, p= 0.011) than double-leg landing. Most differences were within a time frame during the landing phase of 30–50 ms in which non-contact ACL injuries are considered to happen. These recorded time frames are consistent with biomechanical measures that are deemed dangerous. To reduce lower limb injury, a volleyball player should consciously swing the arms to influence the body to maintain a better-balanced state. Adjusting the landing mode of the lower limbs can achieve a good cushioning effect during landing following a spike shot.

Synthesizing silver nanoparticles (AgNPs) from medicinal plants is an emerging and eco-friendly biosynthetic route. An aqueous extract of Picrasma quassioides(P. quassioides) leaves was used for the synthesis of AgNPs. The synthesized AgNPs were characterized using different methods, namely; ultraviolet–visible (UV–Vis) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), transmission electron microscope (TEM), dynamic light scattering (DLS) and atomic force microscope (AFM). The UV–Vis spectrum of the synthesized AgNPs showed absorption peak at 412 nm. The FTIR study provides evidence for the occurrence of possible biomolecules responsible for the reduction of silver ions to a zero-valent metal as well as capping agent that helps in increasing the stability of the fabricated AgNPs. The XRD pattern analysis revealed peaks at 38.35° (111), 46.75° (200), 64.65° (220) and 77.75° (311) corresponding to the diffraction facets of silver. TEM, AFM and SEM analysis showed that the AgNPs were almost spherical in shape with an average size of 5–40 nm. Cytotoxic and radiosensitization potential of AgNPs formulation was determined on HepG-2 cell lines.