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THE RELATIONSHIP BETWEEN PITCH VELOCITY AND SHOULDER DISTRACTION FORCE AND ELBOW VALGUS TORQUE IN COLLEGIATE AND HIGH SCHOOL PITCHERS
Get PDFThe purpose of this study was to 1) determine the relationship between baseball pitching velocity, shoulder distraction force, and elbow valgus torque, and 2) compare these relationships between college and high school baseball pitchers. Biomechanical pitching reports from collegiate and high school baseball pitchers were analysed with linearity not assumed. A total of 273 pitches were included in this study. Pitching velocity exhibits a positive linear relationship with both shoulder distraction force and elbow valgus torque among high school and college pitchers. However, when only examining pitches thrown above 85 mph, only high school pitches have a positive linear relationship between pitching velocity and elbow valgus torque. Despite assuming non-linearity, pitching velocity exhibited a positive linear relationship with both shoulder distraction force and elbow valgus torque. Lower powered secondary analyses should be interpreted with caution
ASSESSMENT OF THE UNCERTAINTY BUDGET FOR AN INTEGRATED SYSTEM IN CLAY PIGEON SHOOTING DISCIPLINE
Get PDFThe purpose of this study was a part of a wider project to characterize the athletic gesture in the Olympic shooting disciplines, expanding the scientific knowledge in clay pigeon shooting. This project aimed to design and develop an integrated measurement system able to acquire and analyse the shooters‘ physical parameters. An uncertainty budget was assessed, identifying the main sources of uncertainty for their measurement, being a preparatory step for the validation of a measurement system, which should be able to identify the most relevant parameters affecting the shooting performance
STEP WIDTH, GLUTEUS MEDIUS ACTIVATION AND POSTURAL SWAY RESPONSES TO A NOVEL GAIT TREATMENT: A PILOT STUDY
Get PDFThe current study explored the acute effect of a novel rehabilitative device (NewGait™) on several interrelated variables associated with gait. Participants completed an eight-minute walking treatment wearing the NewGait™. Postural sway (center of pressure velocity), step width, and gluteus medius (GM) muscle activity were measured before during and after the treatment. No significant changes were noted in step width or GM activity during the treatment. Step width narrowed significantly after the treatment (p=0.02) and postural sway improved in the eyes open condition (p=0.02). These results indicate gait changes in healthy participant’s following use of the NewGait™ device. However, due to the acute nature of this investigation, it is unclear if balance improvements noted are due to the walking activity alone or walking while wearing the NewGait™ device
EFFECTS OF PNF INTERVENTION ON PAIN, JOINT PROPRIOCEPTION AND KNEE MOMENTS IN THE ELDERLY WITH KNEE OSTEOARTHRITIS DURING STAIR ASCENDING
Get PDFIn this study, we aimed to explore the effects of a 6-week proprioceptive neuromuscular facilitation (PNF) intervention on stair pain, joint proprioception, and external knee moment in the elderly patients with knee osteoarthritis (KOA) during stair ascending. A total of 27 elderly patients with KOA participated in our study. Fourteen of the patients were included in the PNF group, and 13 were included in the control group. The WOMAC measures for specific pain and joint motion sense measures were used, and gait test were performed at weeks 0 and 6. After a 6-week PNF intervention, the PNF group showed a decreased “using stairs” pain score, decreased difficulty with “climbing stairs” score, decreased joint kinesthesia threshold, increased knee flexion moment (KFM), and decreased knee adduction moment (KAM) during climbing stairs. We suggest the use of PNF intervention, which relieves joint pain, enhances muscles strength and proprioception recovery, increases KFM, and decreases KAM, in the treatment of KOA in elderly patients
BODY WAVE CHARACTERISTICS AND VARIABILITY OF AN INTERNATIONAL AND A REGIONAL LEVEL SWIMMER IN 50 M BUTTERFLY SWIMMING
Get PDFThe purpose of this study was to compare body wave characteristics between butterfly swimmers with different competitive levels as a case study. An international and a regional level swimmer performed a 50 m butterfly with their maximum effort, and their one stroke cycle velocity, stroke frequency, stroke length, and the vertical coordinate of the shoulder, hip, knee, and ankle joint were quantified for each stroke. The vertical coordinate data were analysed by a Fourier analysis to establish the amplitude, phase angle, contribution to the total signal of harmonic with one maxima/minima (due to one arm stroke motion in a cycle: H1) and two maxima/minima (related to two kicks in a cycle: H2). The velocity of each harmonic travelling caudally between shoulder and hip, hip and knee, and knee and ankle was also obtained. The international swimmer was faster by 23% with 17% longer stroke length and 6% higher stroke frequency than the regional swimmer. The international swimmer was also characterised by lower inter-stroke variability in the amplitude, contribution, and wave velocity of H1 and H2, suggesting that the international swimmer has a more stable rhythm and coordination between the upper and lower body compared with the regional swimmer. The international swimmer had a larger contribution of H1 to the vertical shoulder motion than the regional swimmer, meaning that the kick motion of the international swimmer originates from a more cephalic part of the body compared with the regional swimmer. The international swimmer generated the shoulder H1 rhythm for one stroke cycle at the end of the preceding cycle whereas the regional swimmer produced the shoulder H1 rhythm at the beginning of each cycle, which might be a reason for the higher stroke frequency of the international swimmer compared with the regional swimmer
WHY IS THE LEFT KNEE RATHER PRONE TO INJURY DURING TEAM HANDBALL-SPECIFIC SIDE-CUTTING MANEUVERS TO THE RIGHT?
Get PDFThe purpose of this study was the biomechanical inter-leg evaluation in three team handball-specific side-cutting maneuvers. This should help to gain a better understanding how different movement executions potentially produce harmful demands to one or both knee joints. Therefore, eight competitive handball player performed the three most common side-cutting maneuvers to the right side (side-cutting maneuver was performed with alternating or simultaneous steps) in a game-like setting in a movement laboratory. Movement data were collected with a 3D motion capture system and two linked 3D force plates. The analysis of the side-cutting maneuvers revealed increased vertical and medio-lateral ground reaction force components on the left leg, which initiated the side-cutting maneuver. The peak knee abduction moments in the weight acceptance phase did not differ between the left and the right leg in all three side-cutting maneuvers. However, higher peak knee valgus angles occurred at the left leg, which increased with increasing stance time. The results of this study indicate that during the performance of handball-specific side-cutting maneuvers to the right, the left knee joint has a greater risk to get injured. Consequently, athletes and coaches should place special focus on the movement execution of the cutting initiating leg to reduce the risk of knee injuries. Furthermore, leg explosive strength and core stability should be in major focus in training exercises to prepare the athlete for the demands in such high intensity movements
CENTRE OF MASS TRAJECTORY IN SNOWBOARD GIANT SLALOM USING INERTIAL SENSORS: LABORATORY AND IN-FIELD PRELIMINARY EVALUATION
Get PDFThe purpose of the present study was to evaluate the reconstruction accuracy of the centre of mass during snowboard giant slalom using inertial sensors (Opal, APDM, 128 Hz). Two approaches were implemented and tested: i) a multi-segment model using 7 inertial sensors on the trunk, the pelvis, the thighs, the shanks, and the board; and ii) a double integration of the acceleration at L5 level measured with one inertial sensor. The accuracy of the algorithms was verified in two laboratory conditions: a) the multi-segment model approach was tested indoor during controlled movements using stereo-photogrammetry as gold standard, and b) the double integration of acceleration approach was tested outdoor in simulated movements on a longboard using GPS as gold standard. Successively, to verify the application in real conditions, an in-field acquisition of a forerunner athlete during a snowboard world cup competition was performed. The position of the centre of mass estimated indoor with multi-segmental model approach reported in the local reference frame of the board showed high correlation with respect to stereo-photogrammetry (r=0.87) and a RMS error of 3.8 [%] expressed as percentage of the range of motion during the trial (1.32m). For the simulated movements test in outdoor conditions on the longboard applying the double integration approach, high correlation was found with respect to the GPS data (r=0.95) on the trajectory but , for the 4 turns trial, a RMS difference on the distance equal to 15.3 [%] expressed as percentage of the whole distance covered (46m). Finally, the in-field acquisition showed how using inertial sensors is a viable option for collecting centre of mass data during training session useful for coaches and athletes. The approach using one sensors at L5 level showed low level of accuracy with respect to the one using a multi-segment model. Further developments should be performed in the direction of a better estimation of the orientation of the inertial sensors and of the boundary conditions for the integration algorithm
CLASSIFICATION OF THE ROTATIONAL SHOT-PUT BASED ON DURATION TIME OF MOTION PHASES
Get PDFThis study aimed to investigate the relationships between throwing distance and duration times of motion phases in the rotational shot-put and attempted to classify the throw based on duration times. A total of 181 recorded trials performed by male shot-putters were obtained, and their duration time and the ratio of duration time of defined motion phases were analysed. Duration time and the ratio of duration time were not correlated with throwing distance for all motion phases. Result of a cluster analysis indicated that athletes could be classified in two groups and there were significant differences in duration time at initiation and later phases between the groups. As a result, it is suggested that the changes in duration time might not influence the throwing distance. In addition, it was identified that there are two kinds of group based on the duration times in the rotational shot-put
EVALUATING SOLUBLE AXL AS A BIOMARKER FOR GLIOBLASTOMA
Get PDFAXL, a receptor tyrosine kinase, is known to promote malignant phenotypes in various types of cancer. AXL overexpression is commonly observed in glioblastoma and correlates with a worse prognosis. Detectable in most biological fluids, the extracellular domain of AXL, sAXL, is the product of enzymatic cleavage by ADAM10/17. Here we used ELISA, BCA and BCG assays to characterize blood serum from 23 newly diagnosed GBM patients which was collected roughly 24 hours before and after surgery as well as every three months post-surgery, corresponding to follow-up treatment visits. Immunoblotting was used to determine relative AXL expression in 13 patient tumor tissue samples. Additionally, T-1 weighted MRI scans were used to interpolate pre-operative tumor volume in all participating patients. Here we report that sAXL was elevated in the 84 GBM samples compared to the 40 control samples (p = 0.013). Normalizing sAXL values against corresponding serum albumin concentrations further defined the distinction between the two groups (p \u3c 0.0001). While in the 19 paired, pre- and post- operative samples, sAXL did not respond significantly to surgical intervention, normalizing the values against albumin showed a significant elevation in response to surgery (p = 0.013). In patients whose pre-operative samples presented with sAXL elevated compared to the healthy control average (30.16 ng/mL), there was a strong positive correlation between sAXL and AXL found in the corresponding tumor tissue. Though sAXL shed from brain tumors is detectable in the serum of GBM patients, in this small series of patients, it does not correlate with tumor volume
RAPID COLORIMETRIC IDENTIFICATION OF ESCHERICHIA COLI SHIGA TOXINS 1 AND 2, AS WELL AS EAE AND AGGR, USING LOOP MEDIATED ISOTHERMAL AMPLIFICATION FOLLOWED BY PNA/AUNP DETECTION
Get PDFEscherichia coli are normal residents in the intestinal tracts of humans and animals. However, some E. coli strains produce Shiga toxins and attachment factors that make them pathogenic. Pathogenic E. coli strains can cause fever, diarrhea, vomiting and abdominal pain. In severe cases they cause hemorrhagic colitis or kidney failure. Current laboratory methods can detect pathogenic E. coli within 24-48 hours. This timeframe puts more people at risk of exposure to pathogenic E. coli. This research utilizes a DNA amplification technique called Loop-Mediated Isothermal Amplification (LAMP) to detect different strains of pathogenic E. coli. Common visualization methods of LAMP amplicons include using LAMP reaction buffer containing a pH indictor dye. This method allows for easy colorimetric detection of LAMP amplicons. If the target sequence was amplified, hydrogen ion release during phosphodiester bond formation will decrease the pH of the reaction. This causes the pH indicator dye to turn from pink to yellow. There are disadvantages to a visualization method that relies solely on pH changes. This is an indirect measure of DNA amplification of the target sequence. To make the LAMP assay more specific, a peptide nucleic acid (PNA) probe complementary to either the Shiga toxin 1 or 2 genes, eae or aggR was introduced, along with gold nanoparticles (AuNP). The PNA-AuNP detection system does not depend on pH change, rather an aggregation or monodispersing of gold nanoparticles that is sequence specific. When the PNA probe detects the specified DNA sequence, it produces a distinguishable color change from blue to red if the target LAMP amplicon DNA is present. This research demonstrates the ability to detect pathogenic E. coli species’ DNA and live cells, as well as from inoculated lettuce sampling, within 90 minutes using LAMP followed by a PNA-AuNP detection system