A Comparison of Kinematic Symmetry of Lower Limbs during Running at Different Speeds

Introduction: Symmetry and asymmetry of lower limbs are introduced as main critical challenges of human movement. The aim of this study was to compare the kinematic symmetry of lower limbs during running at different speeds. Material and Methods: The study was conducted as a quasi-experimental design. Twenty-eight professional runners (aged: 34.75±6.63 years) voluntarily participated in this study. Running at three progressive speeds (2.5, 3.5 and 4.5 m/s) was conducted by each subject on a treadmill while kinematic data were captured at 150 Hz. Peak angle of hip, knee and ankle joints during flexion were derived in the stance phase of running. Independent T-test were performed to examine the symmetry of peak flexion angles of hip, knee and ankle joints during running at different speeds using SPSS ver. 22 (P<0.05). Results: Findings showed no significant difference between two limbs in peak flexion angles of lower joints at every speed. Conclusions: Symmetry exists in peak flexion angles of lower joints in stance phase during running at the different progressive speeds. Coaches and biomechanists would achieve benefits of kinematic symmetry of lower joints in order to prevent injuries and optimize athletes’ running performance

Three Planar Symmetry of Hip, Knee and Ankle Joints’ Moments during Running: Three planar Symmetry of Hip, Knee and Ankle Joints’ moments during Running

Introduction: Symmetry and asymmetry of the limbs’ movement pattern during running are introduced as one of the main critical challenges of human locomotion. The aim of this study was to investigate three planar symmetry of hip, knee and ankle joints’ moments during running at a fixed speed. Methods and Materials: the present study was conducted as a quasi-experimental study. Elite runner (age: 34.75±6.63 years) participated in this study. Running at constant speed was conducted by each subject at 2/5 m.s-1 on treadmill while kinematic (Raptor-4 motion analysis) and kinetic data (Force plate, Bertec) were captured at 150 Hz and 300 Hz, respectively. The internal joint moments in each plane were represented in the joint-coordinate system and were calculated using a standard inverse-dynamics approach and were normalized by the subject’s body mass as well as running cycle over 101 time points. Independent t tests were conducted to examine the symmetry of hip, knee and ankle moments between dominant and non-dominant joints during stance phase of running (P<0.05). Results: results of the present study showed no significant difference between two limb’s peak moments of lower joints in every three plane. Highest values of the dominant limb’s peak moments in sagittal, frontal and transvers plane were derived in (knee, ankle, hip), (hip, knee, ankle) and (knee, ankle, hip) respectively. Conclusion: Symmetry exists in lower joints three planar moments during running at the constant speed. According to the results dominant and non- dominant lower joints play propulsive and absorbent roles cooperatively

An efficient and optimized protocol for tall fescue tissue culture and Agrobacterium-mediated genetic transformation

Festuca arundinacea Schreb. as an important turf widely exposed to biotic and abiotic stresses. Therefore, optimization of an efficient in vitro culture and transformation method to create optimal traits and tolerance against stresses as a major problem, is essential. In this research, in order to callus induction, embryos of ‘Barlexas II’, ‘Barvado’, ‘Coronado TDH’, and ‘Finelawn Elite’ cultivars were transferred on callogenesis medium containing 0–15 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) and after callus formation, the explants cultured on the regeneration medium added with 0–1.75 mg/L 6-benzyladenine (BA). Out of the four cultivars tested, ‘Barvado’ in 7.5 mg/L (51.83 %), and ‘Finelawn Elite’ in 10 mg/L 2,4-D (54.06 %) had better callusing, respectively. However, regeneration percentage was higher in ‘Barlexas II’ (73.15 %) and ‘Finelawn Elite’ (70 %) in 0.5 mg/L BA. Transformation was done in Murashige and Skoog (MS) modified medium by Agrobacterium tumefaciens strain LBA4404 harboring binary vector pCAMBIA 2301. Transgenic calli and plantlets were confirmed by GUS gene expression as non-destructive, non-invasive and useful marker. Maximum rate of callus transformation was shown on modified medium type 11 for ‘Coronado TDH’ and ‘Barlexas II’ (23 % and 22 %, respectively). When the calli samples were placed on the selection media, a high rate of calli (with no successful activity of neomycin phosphotransferase II (NPTII)) had not the ability to regenerate and died. Therefore, the highest rate of regenerated transgenic plantlets containing NPTII and GUS genes (6 %) was belonged to medium type 6 and ‘Coronado TDH’