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  1. Book: Andrew M. Greeley

    Harrison, Elizabeth

    an annotated bibliography

    (Scarecrow author bibliographies ; 92)

    1994  

    Author's details by Elizabeth Harrison
    Series title Scarecrow author bibliographies ; 92
    Language English
    Size xvii, 389 p, 23 cm
    Publisher Scarecrow Press
    Publishing place Metuchen, N.J u.a.
    Document type Book
    Note Includes indexes
    ISBN 0810829312 ; 9780810829312
    Database Former special subject collection: coastal and deep sea fishing

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  2. Article ; Online: Reliability of mechanical properties of the plantar flexor muscle tendon unit with consideration to joint angle and sex.

    Crotty, Evan D / Furlong, Laura-Anne M / Harrison, Andrew J

    PloS one

    2023  Volume 18, Issue 6, Page(s) e0287431

    Abstract: The reliability of mechanical measures can be impacted by the protocol used, including factors such as joint angle and the sex of participants. This study aimed to determine the inter-day reliability of plantar flexor mechanical measures across ankle ... ...

    Abstract The reliability of mechanical measures can be impacted by the protocol used, including factors such as joint angle and the sex of participants. This study aimed to determine the inter-day reliability of plantar flexor mechanical measures across ankle joint angles and contraction types and consider potential sex-specific effects. 14 physically-active individuals participated in two identical measurement sessions involving involuntary and voluntary plantar flexor contractions, at three ankle angles (10° plantarflexion (PF), 0° (anatomical zero (AZ)), and 10° dorsiflexion (DF)), while torque and surface EMG were recorded. The reliability of mechanical parameters of maximal voluntary torque (MVT), rate of torque development (RTD), electromechanical delay, and tendon stiffness were assessed using absolute and relative reliability measures. MVT measures were reliable across ankle angles. RTD measures showed good group level reliability and moderate reliability for an individual during the early phase of contraction across ankle angles. Explosive voluntary torque measures tended to be less reliable from 50 ms onward, with varied reliability across angles for late-phase RTD. Tendon stiffness demonstrated the best reliability at the DF angle. Sex-based differences in the reliability of tendon measures found that females had significantly different initial tendon length between testing sessions. Despite this, tendon excursion, force, and stiffness measures demonstrated similar reliability compared to males. Ankle angle changes influence the reliability of plantar flexor mechanical measurements across contraction types, particularly for voluntary contractions. These results highlight the importance of establishing potential protocol effects on measurement reliability prior to quantifying plantar flexor mechanical measures.
    MeSH term(s) Male ; Female ; Humans ; Reproducibility of Results ; Muscle, Skeletal/physiology ; Tendons ; Muscle Contraction/physiology ; Ankle ; Electromyography/methods ; Ankle Joint/physiology ; Isometric Contraction/physiology ; Torque
    Language English
    Publishing date 2023-06-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0287431
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Neuromuscular Plantar Flexor Performance of Sprinters versus Physically Active Individuals.

    Crotty, Evan D / Furlong, Laura-Anne M / Harrison, Andrew J

    Medicine and science in sports and exercise

    2023  Volume 56, Issue 1, Page(s) 82–91

    Abstract: Introduction: Comparison of the neuromuscular performance of different athlete types may give insight into the in vivo variability of these measures and their underpinning mechanisms. The study aims to compare the neuromuscular function of the plantar ... ...

    Abstract Introduction: Comparison of the neuromuscular performance of different athlete types may give insight into the in vivo variability of these measures and their underpinning mechanisms. The study aims to compare the neuromuscular function of the plantar flexors of sprinters and physically active individuals to assess any differences in explosive force performance.
    Methods: Neuromuscular performance of a group of sprinters (highly trained/national level, n = 12; elite/international level, n = 2) and physically active individuals ( n = 14) were assessed during involuntary, explosive, and maximum voluntary isometric plantar flexions, across different muscle-tendon unit (MTU) lengths (10° plantarflexion, 0° (anatomical zero/neutral), and 10° dorsiflexion). Plantarflexion rate of torque development (RTD) was measured in three 50-ms time windows from their onset. The synchronous activation of the plantar flexor agonist muscles was calculated as the time difference between 1) the first and last muscle onset and 2) the onsets of the two gastrocnemii muscles. Muscle size and MTU stiffness were assessed using sonograms of the medial gastrocnemius and myotendinous junction.
    Results: Sprinters exhibited greater involuntary RTD across time points (0-50 ms, 50-100 ms) and MTU lengths. In addition, sprinters demonstrated greater early phase voluntary RTD (0-50 ms, 50-100 ms) across MTU lengths. Sprinters also demonstrated greater late-phase RTD (100-150 ms), and relative maximal voluntary torque at the DF angle only. The sprinters demonstrated a more synchronous activation of the gastrocnemii muscles. There were no observable differences in muscle size and MTU stiffness between groups.
    Conclusions: These findings suggest sprint-specific training could be a contributing factor toward improved explosive performance of the plantar flexors, particularly in the early phase of muscular contraction, evidenced by the greater explosive torque producing capabilities of sprinters.
    MeSH term(s) Humans ; Isometric Contraction/physiology ; Muscle, Skeletal/physiology ; Tendons/physiology ; Muscle Contraction/physiology ; Torque ; Electromyography
    Language English
    Publishing date 2023-08-30
    Publishing country United States
    Document type Journal Article
    ZDB-ID 603994-7
    ISSN 1530-0315 ; 0195-9131 ; 0025-7990
    ISSN (online) 1530-0315
    ISSN 0195-9131 ; 0025-7990
    DOI 10.1249/MSS.0000000000003288
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Ankle and Plantar Flexor Muscle-Tendon Unit Function in Sprinters: A Narrative Review.

    Crotty, Evan D / Furlong, Laura-Anne M / Harrison, Andrew J

    Sports medicine (Auckland, N.Z.)

    2023  Volume 54, Issue 3, Page(s) 585–606

    Abstract: Maximal sprinting in humans requires the contribution of various muscle-tendon units (MTUs) and joints to maximize performance. The plantar flexor MTU and ankle joint are of particular importance due to their role in applying force to the ground. This ... ...

    Abstract Maximal sprinting in humans requires the contribution of various muscle-tendon units (MTUs) and joints to maximize performance. The plantar flexor MTU and ankle joint are of particular importance due to their role in applying force to the ground. This narrative review examines the contribution of the ankle joint and plantar flexor MTUs across the phases of sprinting (start, acceleration, and maximum velocity), alongside the musculotendinous properties that contribute to improved plantar flexor MTU performance. For the sprint start, the rear leg ankle joint appears to be a particularly important contributor to sprint start performance, alongside the stretch-shortening cycle (SSC) action of the plantar flexor MTU. Comparing elite and sub-elite sprinters revealed that elite sprinters had a higher rate of force development (RFD) and normalized average horizontal block power, which was transferred via the ankle joint to the block. For the acceleration phase, the ankle joint and plantar flexor MTU appear to be the most critical of the major lower limb joints/MTUs. The contribution of the ankle joint to power generation and positive work is minimal during the first stance, but an increased contribution is observed during the second stance, mid-acceleration, and late-acceleration. In terms of muscular contributions, the gastrocnemius and soleus have distinct roles. The soleus acts mainly as a supporter, generating large portions of the upward impulse, whereas the gastrocnemius acts as both an accelerator and a supporter, contributing significantly to propulsive and upward impulses. During maximum velocity sprinting the ankle joint is a net dissipater of energy, potentially due to the greater vertical loading placed on the plantar flexors. However, the ankle joint is critical for energy transfer from proximal joints to ground force application to maintain velocity. In terms of the contribution of musculoskeletal factors to ankle joint and plantar flexor performance, an optimal plantar flexor MTU profile potentially exists, which is possibly a combination of several musculoskeletal factors, alongside factors such as footwear and technique.
    MeSH term(s) Humans ; Ankle ; Ankle Joint ; Biomechanical Phenomena ; Tendons ; Muscle, Skeletal
    Language English
    Publishing date 2023-11-21
    Publishing country New Zealand
    Document type Journal Article ; Review
    ZDB-ID 605911-9
    ISSN 1179-2035 ; 0112-1642
    ISSN (online) 1179-2035
    ISSN 0112-1642
    DOI 10.1007/s40279-023-01967-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: The Relationship Between the Isometric Squat and Stretch Shortening Cycle Function and Sprint Acceleration Performance in Hurling Players.

    Brady, Claire J / Harrison, Andrew J / Flanagan, Eamonn P / Haff, Guy Gregory / Comyns, Thomas M

    Journal of strength and conditioning research

    2024  

    Abstract: ... completed 3 × 30-m sprints with splits taken at 5, 10, 20, and 30 m. Pearson's product moment correlations ... and 0-5 m and 5-10 m, significant moderate and large negative correlations between CMJ and all splits ... and significant large correlations between RSI and splits over 5 m. Force at 100 ms distinguished ...

    Abstract Abstract: Brady, CJ, Harrison, AJ, Flanagan, EP, Haff, GG, and Comyns, TM. The relationship between the isometric squat and stretch shortening cycle function and sprint acceleration performance in hurling players. J Strength Cond Res XX(X): 000-000, 2024-The primary aim was to examine the relationship between sprint acceleration performance and the performance tests: isometric squat (ISqT), countermovement jump (CMJ), and reactive strength index (RSI). The secondary aim determined whether these tests could distinguish between sprint performance levels. Twenty-six male under-21 subjects completed the ISqT, with peak force (PF), relative PF, force at 100, 150, and 200 milliseconds (ms), and impulse (0-200 ms) measured. Jump height (JH) was calculated from the CMJ and RSI during the 10-5 repeated jump test. Subjects completed 3 × 30-m sprints with splits taken at 5, 10, 20, and 30 m. Pearson's product moment correlations were used to assess the relationships between measures, and independent samples t tests were used to determine whether differences existed in sprint ability of those in the top and bottom quartiles for force at 100 ms, CMJ, and RSI. Significant negative moderate correlations were reported between force at 100 ms and 0-5 m and 5-10 m, significant moderate and large negative correlations between CMJ and all splits and significant large correlations between RSI and splits over 5 m. Force at 100 ms distinguished between performance levels from 0 to 5 m, CMJ from 10 to 20 m, and RSI from 20 to 30 m; faster subjects produced significantly higher force, JHs, and RSI scores. Three principal components explaining 86.1% of the variation in the data set were identified: sprint times and stretch shortening cycle capabilities (33.3%), time-specific force (29.9%), and absolute and relative strength (22.8%).
    Language English
    Publishing date 2024-03-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1156349-7
    ISSN 1533-4287 ; 1064-8011
    ISSN (online) 1533-4287
    ISSN 1064-8011
    DOI 10.1519/JSC.0000000000004759
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Medical Students Call for Single-Payer National Health Insurance.

    Harrison, Andrew M

    Academic medicine : journal of the Association of American Medical Colleges

    2017  Volume 92, Issue 6, Page(s) 735

    MeSH term(s) Attitude ; Delivery of Health Care ; National Health Programs ; Students, Medical
    Language English
    Publishing date 2017-06-14
    Publishing country United States
    Document type Letter ; Comment
    ZDB-ID 96192-9
    ISSN 1938-808X ; 1040-2446
    ISSN (online) 1938-808X
    ISSN 1040-2446
    DOI 10.1097/ACM.0000000000001699
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Letter to the Editor Regarding "Assessing the Impact of Changes to USMLE Step 1 Grading on Evaluation of Residency Applicants in the United States: A Program Director Survey".

    Lew, Harrison D / Nguyen, Andrew / Sharaf, Ramy M / Diaz, Michael J

    World neurosurgery

    2023  Volume 172, Page(s) 112–113

    MeSH term(s) Humans ; United States ; Internship and Residency ; Educational Measurement ; Surveys and Questionnaires
    Language English
    Publishing date 2023-04-04
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2534351-8
    ISSN 1878-8769 ; 1878-8750
    ISSN (online) 1878-8769
    ISSN 1878-8750
    DOI 10.1016/j.wneu.2022.12.067
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Reliability of mechanical properties of the plantar flexor muscle tendon unit with consideration to joint angle and sex.

    Evan D Crotty / Laura-Anne M Furlong / Andrew J Harrison

    PLoS ONE, Vol 18, Iss 6, p e

    2023  Volume 0287431

    Abstract: The reliability of mechanical measures can be impacted by the protocol used, including factors such as joint angle and the sex of participants. This study aimed to determine the inter-day reliability of plantar flexor mechanical measures across ankle ... ...

    Abstract The reliability of mechanical measures can be impacted by the protocol used, including factors such as joint angle and the sex of participants. This study aimed to determine the inter-day reliability of plantar flexor mechanical measures across ankle joint angles and contraction types and consider potential sex-specific effects. 14 physically-active individuals participated in two identical measurement sessions involving involuntary and voluntary plantar flexor contractions, at three ankle angles (10° plantarflexion (PF), 0° (anatomical zero (AZ)), and 10° dorsiflexion (DF)), while torque and surface EMG were recorded. The reliability of mechanical parameters of maximal voluntary torque (MVT), rate of torque development (RTD), electromechanical delay, and tendon stiffness were assessed using absolute and relative reliability measures. MVT measures were reliable across ankle angles. RTD measures showed good group level reliability and moderate reliability for an individual during the early phase of contraction across ankle angles. Explosive voluntary torque measures tended to be less reliable from 50 ms onward, with varied reliability across angles for late-phase RTD. Tendon stiffness demonstrated the best reliability at the DF angle. Sex-based differences in the reliability of tendon measures found that females had significantly different initial tendon length between testing sessions. Despite this, tendon excursion, force, and stiffness measures demonstrated similar reliability compared to males. Ankle angle changes influence the reliability of plantar flexor mechanical measurements across contraction types, particularly for voluntary contractions. These results highlight the importance of establishing potential protocol effects on measurement reliability prior to quantifying plantar flexor mechanical measures.
    Keywords Medicine ; R ; Science ; Q
    Subject code 796
    Language English
    Publishing date 2023-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Role of electron localisation in H adsorption and hydride formation in the Mg basal plane under aqueous corrosion: a first-principles study.

    Li, Bingxin / Xiao, Chengcheng / Harrison, Nicholas M / Fogarty, Richard M / Horsfield, Andrew P

    Physical chemistry chemical physics : PCCP

    2023  Volume 25, Issue 8, Page(s) 5989–6001

    Abstract: Understanding hydrogen-metal interactions is important in various fields of surface science, including the aqueous corrosion of metals. The interaction between atomic H and a Mg surface is a key process for the formation of sub-surface Mg hydride, which ... ...

    Abstract Understanding hydrogen-metal interactions is important in various fields of surface science, including the aqueous corrosion of metals. The interaction between atomic H and a Mg surface is a key process for the formation of sub-surface Mg hydride, which may play an important role in Mg aqueous corrosion. In the present work, we performed first-principles Density Functional Theory (DFT) calculations to study the mechanisms for hydrogen adsorption and crystalline Mg hydride formation under aqueous conditions. The Electron Localisation Function (ELF) is found to be a promising indicator for predicting stable H adsorption in the Mg surface. It is found that H adsorption and hydride layer formation is dominated by high ELF adsorption sites. Our calculations suggest that the on-surface adsorption of atomic H, OH radicals and atomic O could enhance the electron localisation at specific sites in the sub-surface region, thus forming effective H traps locally. This is predicted to result in the formation of a thermodynamically stable sub-surface hydride layer, which is a potential precursor of the crucial hydride corrosion product of magnesium.
    Language English
    Publishing date 2023-02-22
    Publishing country England
    Document type Journal Article
    ZDB-ID 1476244-4
    ISSN 1463-9084 ; 1463-9076
    ISSN (online) 1463-9084
    ISSN 1463-9076
    DOI 10.1039/d2cp05242c
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Joint movement patterns differ among male recreational runners with different running style.

    Floría, Pablo / Harrison, Andrew J / Rojo-Álvarez, Jose Luis / Melgarejo-Meseguer, Francisco M / Sanchez-Sixto, Alberto

    Sports biomechanics

    2024  , Page(s) 1–12

    Abstract: The purpose of this study was to analyse the differences in joint kinematic patterns among runners with different spatiotemporal characteristics in the running cycle. Lower extremity kinematic data and spatiotemporal stride parameters were collected for ... ...

    Abstract The purpose of this study was to analyse the differences in joint kinematic patterns among runners with different spatiotemporal characteristics in the running cycle. Lower extremity kinematic data and spatiotemporal stride parameters were collected for ninety-two recreational runners during a treadmill run at a self-selected comfortable speed. A K-means clustering analysis was conducted on normalised stride cadence and Duty Factor to identify running style. Cluster 1 characterised by reduced stance times and low Duty Factor; Cluster 2, long stance times and low stride cadence; Cluster 3, high Duty Factor and stride cadence. Functional principal component analysis was used to identify patterns of variability between runners. Runners who used a combination of high cadence and Duty Factor showed differences in hip, knee and ankle sagittal kinematics compared to other runners. On the contrary, the joint kinematics was not altered when the Duty Factor was increased along with a decrease in the stride cadence. This study has demonstrated that the combination of several spatial-temporal parameters of the running cycle should be considered when analysing the movement pattern of the lower limb.
    Language English
    Publishing date 2024-01-08
    Publishing country England
    Document type Journal Article
    ISSN 1752-6116
    ISSN (online) 1752-6116
    DOI 10.1080/14763141.2023.2298947
    Database MEDical Literature Analysis and Retrieval System OnLINE

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