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  1. Article ; Online: Upper Extremity Muscle Activation during Drive Volley and Groundstroke for Two-Handed Backhand of Female Tennis Players.

    Tai, Mu-Lin / Yang, Chun-Ju / Tang, Wen-Tzu / Elliott, Bruce / Chang, Kai-Lung

    Journal of sports science & medicine

    2022  Volume 21, Issue 4, Page(s) 586–594

    Abstract: Drive volley is one of the essential backhand stroke technique trends seen in recent women's tennis competitions. Although movements of the drive volley and groundstroke are similar, activation of the internal muscles vary due to different incoming ball ... ...

    Abstract Drive volley is one of the essential backhand stroke technique trends seen in recent women's tennis competitions. Although movements of the drive volley and groundstroke are similar, activation of the internal muscles vary due to different incoming ball conditions. Most previous studies only focused on the groundstroke, however. The current study investigates the different muscle activation patterns in the upper extremity muscle during the two-handed backhand drive volley as well as the groundstroke for female tennis players. Ten elite female tennis players were measured in the muscle activation of the flexor carpi radialis (FCR), extensor carpi radialis (ECR), biceps brachii (BB), and triceps brachii (TB) from both upper extremities. Racket-head speed at impact, swing duration of each phase, and racket-head average velocity in both strokes were also recorded. Significant differences were found between the drive volley and groundstroke in the velocity profile of racket tip, swing duration of each phase (preparation, early follow-through, and late follow-through), activation patterns of upper extremity muscles, and flexor/ extensor ratios of wrist and elbow in both upper extremities. Different racket trajectory strategies were also observed between the two strokes, with greater horizontal racket velocity recorded in the groundstroke but greater vertical velocity in the drive volley. ECR and TB muscle activation during the drive volley preparation phase was greater than the groundstroke when completing a quicker backswing. In the early acceleration phase, the greater FCR leading arm activation in the drive volley assisted wrist stabilization in preparation for impact. In the late follow-through phase, less TB leading arm activity and higher ECR trailing arm activity in the drive volley showed more forward compression movement in racket contact with the ball. As it is essential for the drive volley to complete a quicker backswing and to increase shot efficiency at the end of the forward movement, coaches should consider the two strokes' muscle activation and technique differences to enhance specific techniques and fitness training programs.
    Language English
    Publishing date 2022-12-01
    Publishing country Turkey
    Document type Journal Article
    ZDB-ID 2075564-8
    ISSN 1303-2968 ; 1303-2968
    ISSN (online) 1303-2968
    ISSN 1303-2968
    DOI 10.52082/jssm.2022.586
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Ezrin, more than a metastatic detERMinant?

    Hoskin, Victoria / Ghaffari, Abdi / Elliott, Bruce E

    Oncotarget

    2019  Volume 10, Issue 63, Page(s) 6755–6757

    Language English
    Publishing date 2019-11-26
    Publishing country United States
    Document type Editorial
    ZDB-ID 2560162-3
    ISSN 1949-2553 ; 1949-2553
    ISSN (online) 1949-2553
    ISSN 1949-2553
    DOI 10.18632/oncotarget.27227
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Conflict of interest and the Society for Vascular Surgery.

    Elliott, Bruce M

    Journal of vascular surgery

    2011  Volume 54, Issue 3 Suppl, Page(s) 3S–11S

    Abstract: Specialty medical societies such as Society for Vascular Surgery (SVS) are instrumental in the development and dissemination of medical knowledge through scientific presentations, publication of rigorously peer-reviewed writings, awarding competitive ... ...

    Abstract Specialty medical societies such as Society for Vascular Surgery (SVS) are instrumental in the development and dissemination of medical knowledge through scientific presentations, publication of rigorously peer-reviewed writings, awarding competitive research and training grants, and the provision of high-quality continuing medical education (CME). It is vital that in these roles the SVS remain in fact and in perception completely free of all influence and bias from industry. While independence from bias has always been necessary, the increasing focus by governmental agencies, industry organizations, and society has made it important for the SVS to address this issue in a formal way. In June 2010, the SVS Board of Directors approved a set of guidelines specifically designed to address management of conflict of interest among its members and its leaders. These guidelines, included in this article, were based on currently available information and policies put forth by legislative bodies, academic medical centers, industry groups, and other professional medical societies, and were designed to safeguard against abuse while maintaining valuable collaboration between vascular surgeons and their industry partners. The guidelines are included in this article.
    MeSH term(s) Bias ; Codes of Ethics ; Conflict of Interest ; Cooperative Behavior ; Diffusion of Innovation ; Health Care Sector/ethics ; Health Care Sector/standards ; Humans ; Interinstitutional Relations ; Interprofessional Relations/ethics ; Leadership ; Scientific Misconduct ; Societies, Medical/ethics ; Societies, Medical/standards ; Vascular Surgical Procedures/ethics ; Vascular Surgical Procedures/standards
    Language English
    Publishing date 2011-09
    Publishing country United States
    Document type Guideline ; Journal Article
    ZDB-ID 605700-7
    ISSN 1097-6809 ; 0741-5214
    ISSN (online) 1097-6809
    ISSN 0741-5214
    DOI 10.1016/j.jvs.2011.04.066
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  4. Article ; Online: The influence of upper-body mechanics, anthropometry and isokinetic strength on performance in wrist-spin cricket bowling.

    Spratford, Wayne / Elliott, Bruce / Portus, Marc / Brown, Nicholas / Alderson, Jacqueline

    Journal of sports sciences

    2019  Volume 38, Issue 3, Page(s) 280–287

    Abstract: Delivering a cricket ball with a wrist-spin (WS) bowling technique is considered one of the game's most difficult skills. Limited biomechanical information exists for WS bowlers across skill levels. The purpose of this study was to compare biomechanical, ...

    Abstract Delivering a cricket ball with a wrist-spin (WS) bowling technique is considered one of the game's most difficult skills. Limited biomechanical information exists for WS bowlers across skill levels. The purpose of this study was to compare biomechanical, isokinetic strength and anthropometric measures between elite (12) and pathway bowlers (eight). Data were collected using a motion analysis system, dynamometer and a level-two anthropometrist. A regression analysis identified that performance was best explained by increased wrist radial deviation torque and longitudinal axis rotational moments at the shoulder and wrist. From back foot impact (BFI) to ball release (BR), elite bowlers rotated their trunks less, experienced less trunk deceleration resulting in a more front-on position and increased pelvis rotation angular velocity. They also displayed an increased shoulder internal rotation moment as the upper arm moved from external into internal rotation and was a major contributor in the subsequent differences observed in the distal segments of the bowling limb. Anthropometric differences were observed at the wrist and finger joints and may be used to form the basis for talent identification programmes. This study highlights the important contribution to bowling performance of the musculature responsible for producing long axis rotations of the bowling limb.
    MeSH term(s) Adolescent ; Adult ; Anthropometry ; Athletic Performance/physiology ; Cricket Sport/physiology ; Humans ; Male ; Motor Skills/physiology ; Muscle Strength/physiology ; Pelvis/physiology ; Range of Motion, Articular/physiology ; Rotation ; Thorax/physiology ; Time and Motion Studies ; Upper Extremity/physiology ; Young Adult
    Language English
    Publishing date 2019-11-25
    Publishing country England
    Document type Journal Article
    ZDB-ID 995528-8
    ISSN 1466-447X ; 0264-0414
    ISSN (online) 1466-447X
    ISSN 0264-0414
    DOI 10.1080/02640414.2019.1696265
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: A Reliable Video-based ACL Injury Screening Tool for Female Team Sport Athletes.

    Weir, Gillian / Alderson, Jacqueline / Smailes, Natalie / Elliott, Bruce / Donnelly, Cyril

    International journal of sports medicine

    2019  Volume 40, Issue 3, Page(s) 191–199

    Abstract: This study aimed to develop a 2-dimensional (2D) video screening tool capable of predicting an athlete's peak 3-dimensional (3D) knee moments during unplanned sidestepping. 2D video-based kinematic measures were simultaneously captured with 3D peak knee ... ...

    Abstract This study aimed to develop a 2-dimensional (2D) video screening tool capable of predicting an athlete's peak 3-dimensional (3D) knee moments during unplanned sidestepping. 2D video-based kinematic measures were simultaneously captured with 3D peak knee moments for 30 female field hockey players (15 junior, 15 senior). Intra- and intertester repeatability of 2D kinematic measures was performed. Then, linear regression models were used to model 3D knee moments from 2D kinematic variables utilizing 80% of the sample (n=24). Regression equations were then validated on the remaining 20% of the sample (n=6). Angular 2D measures had good-excellent intra- (ICC=0.936-0.998) and intertester (ICC=0.662-0.949) reliability. Displacement measures had poor-excellent intra- (ICC=0.377-0.539) and inter-tester (ICC=0.219-0.869) reliability. Significant independent predictors of peak knee moments were dynamic knee valgus, knee flexion angle at foot strike, trunk flexion range of motion (ROM), trunk lateral flexion, hip abduction and knee flexion ROM (P<0.05). Regression equations generated from these models effectively predicted peak knee extension, valgus and internal rotation moments (i. e., were not different from measured values P>0.05, ES<0.4) in the 20% subsample. 2D video-based measurements of an athlete's full body kinematics during unplanned sidestepping provide a reliable, specific, sensitive and cost-effective means for screening female team sport athletes.
    MeSH term(s) Adolescent ; Anterior Cruciate Ligament Injuries/diagnosis ; Anterior Cruciate Ligament Injuries/physiopathology ; Biomechanical Phenomena ; Female ; Foot/physiopathology ; Hip/physiopathology ; Hockey/injuries ; Humans ; Knee Joint/physiopathology ; Linear Models ; Mass Screening/methods ; Movement ; Range of Motion, Articular ; Torso/physiopathology ; Video Recording ; Young Adult
    Language English
    Publishing date 2019-01-10
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 603122-5
    ISSN 1439-3964 ; 0172-4622 ; 0943-917X
    ISSN (online) 1439-3964
    ISSN 0172-4622 ; 0943-917X
    DOI 10.1055/a-0756-9659
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  6. Article ; Online: Illegal bowling actions contribute to performance in cricket finger-spin bowlers.

    Spratford, Wayne / Elliott, Bruce / Portus, Marc / Brown, Nicholas / Alderson, Jacqueline

    Scandinavian journal of medicine & science in sports

    2018  Volume 28, Issue 6, Page(s) 1691–1699

    Abstract: With advances in technology, scientists are now able to more accurately measure elbow displacement changes during the cricket bowling action. This has led to the realization that the majority of bowlers undergo some degree of elbow extension during the ... ...

    Abstract With advances in technology, scientists are now able to more accurately measure elbow displacement changes during the cricket bowling action. This has led to the realization that the majority of bowlers undergo some degree of elbow extension during the forward swing phase of bowling. Consequently, the International Cricket Council were obliged to revise the once zero tolerance for elbow extension threshold to a 15° range. However, it is still not understood if bowling with >15° of elbow extension aids performance or alters other kinematic movements. The purpose of this study was to compare performance and technique measures between legal and illegal finger-spin bowlers. Data were collected from 48 pathway and elite bowlers using a 22-camera motion analysis system. Results indicated that the ball velocity and revolutions at ball release of pathway bowlers with illegal actions showed no significant difference and were similar to elite legal bowlers. Technique differences were also identified, with illegal bowlers being more front-on, forcing a reliance on increased elbow flexion and supination to impart effective ball kinematics at ball release. The performance benefit of greater ball velocity and revolutions is obtained when finger-spin bowlers deliver the ball with more than the allowable 15° of elbow extension, thus reinforcing the validity of the current bowling laws. To counteract bowling with an illegal action, it is recommended that a more side-on technique at back foot impact and rotating the trunk through to the point of ball release will assist bowlers in reducing undesirable elbow extension levels.
    MeSH term(s) Adolescent ; Adult ; Athletic Performance/standards ; Biomechanical Phenomena ; Elbow/physiology ; Fingers/physiology ; Foot ; Humans ; Male ; Rotation ; Sports/standards ; Task Performance and Analysis ; Torso ; Video Recording ; Young Adult
    Language English
    Publishing date 2018-06
    Publishing country Denmark
    Document type Journal Article
    ZDB-ID 1077418-x
    ISSN 1600-0838 ; 0905-7188
    ISSN (online) 1600-0838
    ISSN 0905-7188
    DOI 10.1111/sms.13070
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  7. Article ; Online: Measurement of uni-planar and sport specific trunk motion using magneto-inertial measurement units: The concurrent validity of Noraxon and Xsens systems relative to a retro-reflective system.

    Cottam, Daniel S / Campbell, Amity C / Davey, Mr Paul C / Kent, Peter / Elliott, Bruce C / Alderson, Jacqueline A

    Gait & posture

    2021  Volume 92, Page(s) 129–134

    Abstract: Background: There is a range of magneto-inertial measurement unit (MIMU) systems commercially available, however sensor specifications and fusion methods vary considerably between manufacturers. Such variability can influence the concurrent validity of ... ...

    Abstract Background: There is a range of magneto-inertial measurement unit (MIMU) systems commercially available, however sensor specifications and fusion methods vary considerably between manufacturers. Such variability can influence the concurrent validity of MIMUs relative to reference standard measurement devices. Different MIMUs have been compared during static or low-velocity conditions, with higher-velocity movements assessed in robotic-based studies. However, there is a need for the concurrent validity of higher-velocity movements to be established in human-based studies.
    Research question: This study aimed to assess the concurrent validity of two commercial MIMU systems (Noraxon and Xsens), relative to a 'gold-standard' retro-reflective motion capture system, when measuring trunk angles during uni-planar range of motion (ROM) and cricket bowling, which involves high-speed, multi-planar movements.
    Methods: For this criterion-based validity study, both MIMU systems incorporated comparable sensor specifications and employed Kalman filter sensor fusion algorithms. The MIMU based angles were compared with angles derived from concurrently captured three-dimensional retro-reflective data for 10 fast-medium bowlers. Statistical parametric mapping and root mean squared differences (RMSD) were computed for both MIMU systems.
    Results: One-dimensional statistical parametric mapping showed no significant differences for angles from both MIMU systems when compared with retro-reflective based angle outputs. The MIMU systems produced ROM RMSDs between 1.4 ± 1.0° and 2.6 ± 1.5°. One system displayed RMSDs between 4.6 ± 1.4° and 7.4 ± 1.9° during bowling, indicating functionally relevant differences to retro-reflective derived angles. There were some small but statistically significant differences in RMSDs between the MIMU systems.
    Significance: MIMU-based angle accuracy is poorer during high-speed, multi-planar movement than uni-planar tasks. Comparable MIMU systems can produce varying measurements during ROM and bowling tasks. It is likely that varying sample rates and sensor fusion algorithm parameters contributed to the differences.
    MeSH term(s) Biomechanical Phenomena ; Humans ; Movement ; Range of Motion, Articular ; Sports ; Torso
    Language English
    Publishing date 2021-11-18
    Publishing country England
    Document type Journal Article
    ZDB-ID 1162323-8
    ISSN 1879-2219 ; 0966-6362
    ISSN (online) 1879-2219
    ISSN 0966-6362
    DOI 10.1016/j.gaitpost.2021.11.012
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Modulation of Akt vs Stat3 activity by the focal adhesion kinase in non-neoplastic mouse fibroblasts.

    Geletu, Mulu / Adan, Hanad / Niit, Maximillian / Arulanandam, Rozanne / Carefoot, Esther / Hoskin, Victoria / Sina, Diana / Elliott, Bruce / Gunning, Patrick / Raptis, Leda

    Experimental cell research

    2021  Volume 411, Issue 1, Page(s) 112731

    Abstract: Adhesion of cells to each other and to the extracellular matrix (ECM) are both required for cellular functions. Cell-to-cell adhesion is mediated by cadherins, and their engagement triggers the activation of Stat3, which offers a potent survival signal. ... ...

    Abstract Adhesion of cells to each other and to the extracellular matrix (ECM) are both required for cellular functions. Cell-to-cell adhesion is mediated by cadherins, and their engagement triggers the activation of Stat3, which offers a potent survival signal. Adhesion to the ECM on the other hand, activates FAK which attracts and activates Src, as well as receptor tyrosine kinases (RTKs), the PI3k/Akt and Ras/Erk pathways. However, the effect of cell density upon FAK and Akt activity has not been examined. We now demonstrate that, interestingly, despite being potent Stat3 activators, Src and RTKs are unable to activate Stat3 in sparsely growing (i.e., without cadherin engagement), non-neoplastic cells attached to the ECM. In contrast, cell aggregation (i.e., cadherin engagement in the absence of adhesion to a solid substratum) was found to activate both Stat3 and Akt. Pharmacologic or genetic reduction of FAK activity abolished Akt activity at low densities, indicating that FAK is an important activator of Akt in this setting. Notably, FAK knockout increased cellular sensitivity to the Stat3 inhibitor CPA7, while FAK reintroduction restored resistance to this drug. These findings suggest a complementary role of integrin/FAK/Akt and cadherin/Stat3-mediated pro-survival pathways, which may be of significance during neoplastic transformation and metastasis.
    Language English
    Publishing date 2021-07-14
    Publishing country United States
    Document type Published Erratum
    ZDB-ID 1493-x
    ISSN 1090-2422 ; 0014-4827
    ISSN (online) 1090-2422
    ISSN 0014-4827
    DOI 10.1016/j.yexcr.2021.112731
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  9. Article ; Online: Erratum to "Modulation of Akt vs Stat3 activity by the focal adhesion kinase in non-neoplastic mouse fibroblasts" [Exp. Cell Res. 404 (1) (2021) 112601].

    Geletu, Mulu / Adan, Hanad / Niit, Maximillian / Arulanandam, Rozanne / Carefoot, Esther / Hoskin, Victoria / Sina, Diana / Elliott, Bruce / Gunning, Patrick / Raptis, Leda

    Experimental cell research

    2021  Volume 411, Issue 1, Page(s) 112732

    Language English
    Publishing date 2021-07-30
    Publishing country United States
    Document type Published Erratum
    ZDB-ID 1493-x
    ISSN 1090-2422 ; 0014-4827
    ISSN (online) 1090-2422
    ISSN 0014-4827
    DOI 10.1016/j.yexcr.2021.112732
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  10. Article ; Online: Functional calibration does not improve the concurrent validity of magneto-inertial wearable sensor-based thorax and lumbar angle measurements when compared with retro-reflective motion capture.

    Cottam, Daniel S / Campbell, Amity C / Davey, Paul C / Kent, Peter / Elliott, Bruce C / Alderson, Jacqueline A

    Medical & biological engineering & computing

    2021  Volume 59, Issue 11-12, Page(s) 2253–2262

    Abstract: Magneto-inertial measurement unit (MIMU) systems allow calculation of simple sensor-to-sensor Euler angles, though this process does not address sensor-to-segment alignment, which is important for deriving meaningful MIMU-based kinematics. Functional ... ...

    Abstract Magneto-inertial measurement unit (MIMU) systems allow calculation of simple sensor-to-sensor Euler angles, though this process does not address sensor-to-segment alignment, which is important for deriving meaningful MIMU-based kinematics. Functional sensor-to-segment calibrations have improved concurrent validity for elbow and knee angle measurements but have not yet been comprehensively investigated for trunk or sport-specific movements. This study aimed to determine the influence of MIMU functional calibration on thorax and lumbar joint angles during uni-planar and multi-planar, sport-specific tasks. It was hypothesised that functionally calibrating segment axes prior to angle decomposition would produce smaller differences than a non-functional method when both approaches were compared with concurrently collected 3D retro-reflective derived angles. Movements of 10 fast-medium cricket bowlers were simultaneously recorded by MIMUs and retro-reflective motion capture. Joint angles derived from four different segment definitions were compared, with three incorporating functionally defined axes. Statistical parametric mapping and root mean squared differences (RMSD) quantified measurement differences one-dimensionally and zero-dimensionally, respectively. Statistical parametric mapping found no significant differences between MIMU and retro-reflective data for any method across bowling and uni-planar trunk movements. The RMSDs for the functionally calibrated methods and non-functional method were not significantly different. Functional segment calibration may be unnecessary for MIMU-based measurement of thorax and lumbar joint angles.
    MeSH term(s) Biomechanical Phenomena ; Calibration ; Humans ; Knee Joint ; Range of Motion, Articular ; Thorax ; Wearable Electronic Devices
    Language English
    Publishing date 2021-09-16
    Publishing country United States
    Document type Journal Article
    ZDB-ID 282327-5
    ISSN 1741-0444 ; 0025-696X ; 0140-0118
    ISSN (online) 1741-0444
    ISSN 0025-696X ; 0140-0118
    DOI 10.1007/s11517-021-02440-9
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