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  1. Article ; Online: A Two-Step Discrete Cosine Basis Oriented Motion Modeling Approach for Enhanced Motion Compensation.

    Ahmmed, Ashek / Paul, Manoranjan / Pickering, Mark

    IEEE transactions on image processing : a publication of the IEEE Signal Processing Society

    2023  Volume 32, Page(s) 4893–4906

    Abstract: Video coding algorithms attempt to minimize the significant commonality that exists within a video sequence. Each new video coding standard contains tools that can perform this task more efficiently compared to its predecessors. Modern video coding ... ...

    Abstract Video coding algorithms attempt to minimize the significant commonality that exists within a video sequence. Each new video coding standard contains tools that can perform this task more efficiently compared to its predecessors. Modern video coding systems are block-based wherein commonality modeling is carried out only from the perspective of the block that need be coded next. In this work, we argue for a commonality modeling approach that can provide a seamless blending between global and local homogeneity information in terms of motion. For this purpose, at first a prediction of the current frame, the frame that need be coded, is generated by performing a two-step discrete cosine basis oriented (DCO) motion modeling. The DCO motion model is employed rather than traditional translational or affine motion model since it has the ability to efficiently model complex motion fields by providing a smooth and sparse representation. Moreover, the proposed two-step motion modeling approach can yield better motion compensation at a reduced computational complexity since an informed guess is designed for initializing the motion search procedure. After that the current frame is partitioned into rectangular regions and the conformance of these regions to the learned motion model is investigated. Depending on the non-conformance to the estimated global motion model, an additional DCO motion model is introduced to increase the local motion homogeneity. In this way, the proposed approach generates a motion compensated prediction of the current frame through the minimization of both global and local motion commonality. Experimental results show an improved rate-distortion performance of a reference high efficiency video coding (HEVC) encoder, specifically up to around 9% savings in bit rate, that employs the DCO prediction frame as a reference frame for encoding the current frame. When compared to the more recent video coding standard, the versatile video coding (VVC) encoder, a bit rate savings of 2.37% is reported.
    Language English
    Publishing date 2023-09-01
    Publishing country United States
    Document type Journal Article
    ISSN 1941-0042
    ISSN (online) 1941-0042
    DOI 10.1109/TIP.2023.3288980
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Team Behavior and Performance: An Exploration in the Context of Professional Rugby Union.

    Serpell, Benjamin G / Colomer, Carmen M / Pickering, Mark R / Cook, Christian J

    International journal of sports physiology and performance

    2023  Volume 18, Issue 9, Page(s) 996–1003

    Abstract: Purpose: To explore complex system behavior and subsequent team performance in professional rugby union.: Methods: Here, we present 2 studies. In the first, we used global positioning system technology to measure player clustering during stoppages in ...

    Abstract Purpose: To explore complex system behavior and subsequent team performance in professional rugby union.
    Methods: Here, we present 2 studies. In the first, we used global positioning system technology to measure player clustering during stoppages in play in nearly 100 games of professional rugby union to explore team (complex system) behavior and performance. In the second, we measured stress hormones (cortisol and testosterone) prior to team meetings and analyzed these relative to amount of time and the frequency with which players looked at peer presenters, as well as subsequent training performance, to explain how stress may lead to behaviors observed in the first study and subsequent match performance.
    Results: No link between player clustering during stoppages of play and performance was observed. When players (complex system agents) demonstrated greater levels of stress (as indicated by greater cortisol-awakening response and a greater decline in testosterone-to-cortisol ratio across the morning), they tended to look at peer presenters more; however, training quality declined (P = .02). Correlational analysis also showed that training quality was related to testosterone-to-cortisol ratio (P = .04).
    Conclusions: Team behavior is complex and can be unpredictable. It is possible that under stress, complex system agents (ie, rugby union players) look at (and cluster toward) their teammates more; however, meaningful interaction may not necessarily occur. Furthermore, while complex system (team) analysis may be valuable strategically in rugby union in the context of describing behavior, without understanding "how" or "why" intrateam/interagent behaviors emerge it may have little meaning.
    MeSH term(s) Humans ; Football/physiology ; Hydrocortisone ; Rugby ; Testosterone ; Geographic Information Systems ; Athletic Performance/physiology
    Chemical Substances Hydrocortisone (WI4X0X7BPJ) ; Testosterone (3XMK78S47O)
    Language English
    Publishing date 2023-07-24
    Publishing country United States
    Document type Journal Article
    ISSN 1555-0273
    ISSN (online) 1555-0273
    DOI 10.1123/ijspp.2023-0085
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Book ; Online: Age determination of sediment cores from the Panama Basin, supplementary data to: Pedersen, Thomas F; Nielsen, B; Pickering, Mark (1991): Timing of Late Quaternary productivity pulses in the Panama Basin and implications for atmospheric CO2. Paleoceanography, 6(6), 657-677

    Pedersen, Thomas F / Nielsen, B / Pickering, Mark

    1991  

    Abstract: High-resolution percent Corg and delta18Oforam records obtained from Panama Basin core Atlantis II 54-25PC and additional data from nearby core P7 show that enhanced burial of organic carbon has characterized every major glacial period for the last 500 ... ...

    Abstract High-resolution percent Corg and delta18Oforam records obtained from Panama Basin core Atlantis II 54-25PC and additional data from nearby core P7 show that enhanced burial of organic carbon has characterized every major glacial period for the last 500 kyr in that area. Both Corg concentration and mass accumulation rate profiles exhibit a sawtooth pattern with maxima occurring typically in the later stages of glacial periods. Comparison with dust records suggests that the carbon accumulation rate profile reflects both the upwelling history and a variable rate of iron input during the late Quaternary. The sawtooth character may derive from increased wind velocities and rates of upwelling during glacials which are indirectly related to ice volume (Sarnthein et al., 1988). The rapid decline in export production at the end of glacials in the equatorial Pacific may be attributed to the retreat of ice sheets (thus reduced wind velocities and upwelling) coupled with a coincident decline in atmospheric dust load and/or delivery rate. The Corg accumulation rate profiles do not correlate well with atmospheric CO2 records. For example, atmospheric CO2 was already at a minimum 40 kyr ago when production in the Panama Basin began increasing dramatically, commensurate with an increase in global dust levels. Using the relationship between the degree of photosynthetic fractionation and the concentration of free CO2 in the surface ocean postulated by Popp et al. (1989), delta13Corg measurements made on core P7 show that Panama Basin surface waters have been supplying CO2 to the atmosphere continually for at least the last 50 kyr. There is no evidence for a flux of CO2 into the surface ocean in this area at any time during this period despite the higher production. If the Panama Basin cores are representative of the eastern and central equatorial Pacific, then these observations weaken the influence on CO2 drawdown postulated for increased glacial productivity at low latitudes.
    Language English
    Dates of publication 1991-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1029/91PA02532
    DOI 10.1594/PANGAEA.727573
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  4. Article ; Online: Financial health and obesity.

    Guariglia, Alessandra / Monahan, Mark / Pickering, Karen / Roberts, Tracy

    Social science & medicine (1982)

    2021  Volume 276, Page(s) 113665

    Abstract: We use individual-level panel data from the English Longitudinal Survey of Ageing over the period 2004-2013 to investigate the links between financial health and obesity. We find that having no debt (high savings) is associated with a 3.6 (1.6) ... ...

    Abstract We use individual-level panel data from the English Longitudinal Survey of Ageing over the period 2004-2013 to investigate the links between financial health and obesity. We find that having no debt (high savings) is associated with a 3.6 (1.6) percentage point lower probability of having a Body Mass Index in excess of 30. Our results are robust to using different estimation methods, to measuring financial health with a subjective indicator, and adiposity with waist circumference. A lower rate of time preference and lower stress levels may be mechanisms which help to explain the association between good financial health and obesity.
    MeSH term(s) Adiposity ; Aging ; Body Mass Index ; Humans ; Obesity/epidemiology ; Waist Circumference
    Language English
    Publishing date 2021-01-06
    Publishing country England
    Document type Journal Article
    ZDB-ID 4766-1
    ISSN 1873-5347 ; 0037-7856 ; 0277-9536
    ISSN (online) 1873-5347
    ISSN 0037-7856 ; 0277-9536
    DOI 10.1016/j.socscimed.2020.113665
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Absence of monitoring in withdrawal of clinically-assisted nutrition and hydration (CANH) and other treatments: a cause for concern?

    Gray, Alice / Pickering, Mark / Sturman, Stephen

    Clinical medicine (London, England)

    2021  Volume 21, Issue 3, Page(s) 235–237

    Abstract: Since 2018, there has been no requirement to bring decisions about the withdrawal of clinically-assisted nutrition and hydration (CANH) in patients with persistent disorders of consciousness before the courts, providing that the requirements of the ... ...

    Abstract Since 2018, there has been no requirement to bring decisions about the withdrawal of clinically-assisted nutrition and hydration (CANH) in patients with persistent disorders of consciousness before the courts, providing that the requirements of the Mental Capacity Act 2005 (MCA) are fulfilled. Subsequent British Medical Association and Royal College of Physicians guidance on CANH withdrawal recommended standards of record keeping and internal and external audit to ensure local decision making was compliant with the MCA to safeguard patients. The scope of the guidance also included patients with stroke and neurodegenerative disorders.Freedom of Information requests made 2 years after the introduction of this guidance have shown that none of the NHS trusts or clinical commissioning groups who responded were undertaking any systematic monitoring of these decisions. Neither is the Care Quality Commission reviewing these decisions, as there is 'no statutory requirement' to do so. It appears there is a lack of organised scrutiny of these highly complex life-ending treatment decisions. This omission must surely be a cause for concern.
    MeSH term(s) Consciousness ; Humans ; Nutritional Status ; Persistent Vegetative State ; Withholding Treatment
    Language English
    Publishing date 2021-05-16
    Publishing country England
    Document type Journal Article
    ZDB-ID 2048646-7
    ISSN 1473-4893 ; 1470-2118
    ISSN (online) 1473-4893
    ISSN 1470-2118
    DOI 10.7861/clinmed.2020-0673
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: A Digital Human for Delivering a Remote Loneliness and Stress Intervention to At-Risk Younger and Older Adults During the COVID-19 Pandemic: Randomized Pilot Trial.

    Loveys, Kate / Sagar, Mark / Pickering, Isabella / Broadbent, Elizabeth

    JMIR mental health

    2021  Volume 8, Issue 11, Page(s) e31586

    Abstract: Background: Loneliness is a growing public health issue that has been exacerbated in vulnerable groups during the COVID-19 pandemic. Computer agents are capable of delivering psychological therapies through the internet; however, there is limited ... ...

    Abstract Background: Loneliness is a growing public health issue that has been exacerbated in vulnerable groups during the COVID-19 pandemic. Computer agents are capable of delivering psychological therapies through the internet; however, there is limited research on their acceptability to date.
    Objective: The objectives of this study were to evaluate (1) the feasibility and acceptability of a remote loneliness and stress intervention with digital human delivery to at-risk adults and (2) the feasibility of the study methods in preparation for a randomized controlled trial.
    Methods: A parallel randomized pilot trial with a mixed design was conducted. Participants were adults aged 18 to 69 years with an underlying medical condition or aged 70 years or older with a Mini-Mental State Examination score of >24 (ie, at greater risk of developing severe COVID-19). Participants took part from their place of residence (independent living retirement village, 20; community dwelling, 7; nursing home, 3). Participants were randomly allocated to the intervention or waitlist control group that received the intervention 1 week later. The intervention involved completing cognitive behavioral and positive psychology exercises with a digital human facilitator on a website for at least 15 minutes per day over 1 week. The exercises targeted loneliness, stress, and psychological well-being. Feasibility was evaluated using dropout rates and behavioral observation data. Acceptability was evaluated from behavioral engagement data, the Friendship Questionnaire (adapted), self-report items, and qualitative questions. Psychological measures were administered to evaluate the feasibility of the trial methods and included the UCLA Loneliness Scale, the 4-item Perceived Stress Scale, a 1-item COVID-19 distress measure, the Flourishing Scale, and the Scale of Positive and Negative Experiences.
    Results: The study recruited 30 participants (15 per group). Participants were 22 older adults and 8 younger adults with a health condition. Six participants dropped out of the study. Thus, the data of 24 participants were analyzed (intervention group, 12; waitlist group, 12). The digital human intervention and trial methods were generally found to be feasible and acceptable in younger and older adults living independently, based on intervention completion, and behavioral, qualitative, and some self-report data. The intervention and trial methods were less feasible to nursing home residents who required caregiver assistance. Acceptability could be improved with additional content, tailoring to the population, and changes to the digital human's design.
    Conclusions: Digital humans are a promising and novel technological solution for providing at-risk adults with access to remote psychological support during the COVID-19 pandemic. Research should further examine design techniques to improve their acceptability in this application and investigate intervention effectiveness in a randomized controlled trial.
    Trial registration: Australia New Zealand Clinical Trials Registry ACTRN12620000786998; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=380113.
    Language English
    Publishing date 2021-11-08
    Publishing country Canada
    Document type Journal Article
    ZDB-ID 2798262-2
    ISSN 2368-7959
    ISSN 2368-7959
    DOI 10.2196/31586
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Shape modelling of the oropharynx distinguishes associations with body morphology but not whiplash-associated disorder.

    Webb, Alexandra L / Lynch, Joseph T / Pickering, Mark R / Perriman, Diana M

    Journal of anatomy

    2022  Volume 242, Issue 3, Page(s) 535–543

    Abstract: Characterization of the oropharynx, a subdivision of the pharynx between the soft palate and the epiglottis, is limited to simple measurements. Structural changes in the oropharynx in whiplash-associated disorder (WAD) cohorts have been quantified using ... ...

    Abstract Characterization of the oropharynx, a subdivision of the pharynx between the soft palate and the epiglottis, is limited to simple measurements. Structural changes in the oropharynx in whiplash-associated disorder (WAD) cohorts have been quantified using two-dimensional (2D) and three-dimensional (3D) measures but the results are inconsistent. Statistical shape modelling (SSM) may be a more useful tool for systematically comparing morphometric features between cohorts. This technique has been used to quantify the variability in boney and soft tissue structures, but has not been used to examine a hollow cavity such as the oropharynx. The primary aim of this project was to examine the utility of SSM for comparing the oropharynx between WAD cohorts and control; and WAD severity cohorts. The secondary aim was to determine whether shape is associated with sex, height, weight and neck length. Magnetic resonance (MR) T1-weighted images were obtained from healthy control (n = 20), acute WAD (n = 14) and chronic WAD (n = 14) participants aged 18-39 years. Demographic, WAD severity (neck disability index) and body morphometry data were collected from each participant. Manual segmentation of the oropharynx was undertaken by blinded researchers between the top of the soft palate and tip of the epiglottis. Digital 3D oropharynx models were constructed from the segmented images and principal component (PC) analysis was performed with the PC weights normalized to z-scores for consistency. Statistical analyses were undertaken using multivariate linear models. In the first statistical model the independent variable was group (acute WAD, chronic WAD, control); and in the second model the independent variable was WAD severity (recovered/mild, moderate/severe). The covariates for both models included height, weight, average neck length and sex. Shape models were constructed to visualize the effect of perturbing these covariates for each relevant mode. The shape model revealed five modes which explained 90% of the variance: mode 1 explained 59% of the variance and primarily described differences in isometric size of the oropharynx, including elongation; mode 2 (13%) primarily described lateral (width) and AP (depth) dimensions; mode 3 (8%) described retroglossal AP dimension; mode 4 (6%) described lateral dimensions at the retropalatal-retroglossal junction and mode 5 (4%) described the lateral dimension at the inferior retroglossal region. There was no difference in shape (mode 1 p = 0.52; mode 2 p = 0.96; mode 3 p = 0.07; mode 4 p = 0.54; mode 5 p = 0.74) between control, acute WAD and chronic WAD groups. There were no statistical differences for any mode (mode 1 p = 0.12; mode 2 p = 0.29; mode 3 p = 0.56; mode 4 p = 0.99; mode 5 p = 0.96) between recovered/mild and moderate/severe WAD. Sex was not significant in any of the models but for mode 1 there was a significant association with height (p = 0.007), mode 2 neck length (p = 0.044) and in mode 3 weight (p = 0.027). Although SSM did not detect differences between WAD cohorts, it did detect associations with body morphology indicating that it may be a useful tool for examining differences in the oropharynx.
    MeSH term(s) Humans ; Whiplash Injuries/diagnostic imaging ; Whiplash Injuries/complications ; Whiplash Injuries/pathology ; Oropharynx/diagnostic imaging ; Magnetic Resonance Imaging/methods ; Palate, Soft/diagnostic imaging ; Models, Statistical
    Language English
    Publishing date 2022-10-27
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2955-5
    ISSN 1469-7580 ; 0021-8782
    ISSN (online) 1469-7580
    ISSN 0021-8782
    DOI 10.1111/joa.13783
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: A Configurational Approach to Mergers and Acquisitions

    Sophie Fischer / John Rodwell / Mark Pickering

    Sustainability, Vol 13, Iss 3, p

    2021  Volume 1020

    Abstract: The processes involved with mergers and acquisitions (M&As) are many, varied and complex. M&A research and practice needs a toolset that can apprehend that complexity and suggest ways forward. This paper shows the complexity of the constituents of ... ...

    Abstract The processes involved with mergers and acquisitions (M&As) are many, varied and complex. M&A research and practice needs a toolset that can apprehend that complexity and suggest ways forward. This paper shows the complexity of the constituents of organizations at a strategic level by building on the natural-resource-based view (NRBV) and the resulting competences and capabilities. In M&As, these resources and capabilities are managed through a variety of forms of acquisition integration comprised of sets of integration mechanisms. M&As occur in a range of strategic contexts and consequently many forms of integration are possible. Accordingly, there is a need for a mode of inquiry examining acquisition integration that can encompass a wide variety of forms, is holistic across a range of possible integration mechanisms and can provide insights. A configurational mode of inquiry can accommodate the complexity of the mechanisms, capabilities and resources, including natural resources, which constitute acquisition integration. A configurational approach emphasizes a holistic synthesis of elements and highlights the importance of thinking of M&As in terms of patterns. A configurational approach offers tools for considering M&As such as analyzing the thematic coherence of integration and enables the inclusion of sustainability into the logic of organizations.
    Keywords mergers and acquisitions ; natural-resource-based view ; configurations ; Environmental effects of industries and plants ; TD194-195 ; Renewable energy sources ; TJ807-830 ; Environmental sciences ; GE1-350
    Language English
    Publishing date 2021-01-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Specular Reflection Detection and Inpainting in Transparent Object through MSPLFI

    Md Nazrul Islam / Murat Tahtali / Mark Pickering

    Remote Sensing, Vol 13, Iss 3, p

    2021  Volume 455

    Abstract: Multispectral polarimetric light field imagery (MSPLFI) contains significant information about a transparent object’s distribution over spectra, the inherent properties of its surface and its directional movement, as well as intensity, which all together ...

    Abstract Multispectral polarimetric light field imagery (MSPLFI) contains significant information about a transparent object’s distribution over spectra, the inherent properties of its surface and its directional movement, as well as intensity, which all together can distinguish its specular reflection. Due to multispectral polarimetric signatures being limited to an object’s properties, specular pixel detection of a transparent object is a difficult task because the object lacks its own texture. In this work, we propose a two-fold approach for determining the specular reflection detection (SRD) and the specular reflection inpainting (SRI) in a transparent object. Firstly, we capture and decode 18 different transparent objects with specularity signatures obtained using a light field (LF) camera. In addition to our image acquisition system, we place different multispectral filters from visible bands and polarimetric filters at different orientations to capture images from multisensory cues containing MSPLFI features. Then, we propose a change detection algorithm for detecting specular reflected pixels from different spectra. A Mahalanobis distance is calculated based on the mean and the covariance of both polarized and unpolarized images of an object in this connection. Secondly, an inpainting algorithm that captures pixel movements among sub-aperture images of the LF is proposed. In this regard, a distance matrix for all the four connected neighboring pixels is computed from the common pixel intensities of each color channel of both the polarized and the unpolarized images. The most correlated pixel pattern is selected for the task of inpainting for each sub-aperture image. This process is repeated for all the sub-aperture images to calculate the final SRI task. The experimental results demonstrate that the proposed two-fold approach significantly improves the accuracy of detection and the quality of inpainting. Furthermore, the proposed approach also improves the SRD metrics (with mean F1-score, G-mean, and accuracy as ...
    Keywords specular reflection detection ; specular reflection inpainting ; transparent object ; multispectral polarimetric imagery ; light field ; Science ; Q
    Language English
    Publishing date 2021-01-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Hamstring musculotendon mechanics of prospectively injured elite rugby athletes.

    Kenneally-Dabrowski, Claire / Brown, Nicholas A T / Serpell, Benjamin G / Perriman, Diana / Spratford, Wayne / Sutherland, Ashlee / Pickering, Mark / Lai, Adrian K M

    Research in sports medicine (Print)

    2023  , Page(s) 1–12

    Abstract: The musculotendon mechanics of the hamstrings during high-speed running are thought to relate to injury but have rarely been examined in the context of prospectively occurring injury. This prospective study describes the hamstring musculotendon mechanics ...

    Abstract The musculotendon mechanics of the hamstrings during high-speed running are thought to relate to injury but have rarely been examined in the context of prospectively occurring injury. This prospective study describes the hamstring musculotendon mechanics of two elite rugby players who sustained hamstring injuries during on-field running. Athletes undertook biomechanical analyses of high-speed running during a Super Rugby pre-season, prior to sustaining hamstring injuries during the subsequent competition season. The biceps femoris long head muscle experienced the greatest strain of all hamstring muscles during the late swing phase. When expressed relative to force capacity, biceps femoris long head also experienced the greatest musculotendon forces of all hamstring muscles. Musculotendon strain and force may both be key mechanisms for hamstring injury during the late swing phase of running.
    Language English
    Publishing date 2023-03-16
    Publishing country England
    Document type Journal Article
    ZDB-ID 2116093-4
    ISSN 1543-8635 ; 1543-8627
    ISSN (online) 1543-8635
    ISSN 1543-8627
    DOI 10.1080/15438627.2023.2189115
    Database MEDical Literature Analysis and Retrieval System OnLINE

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