527 research outputs found

    Object-Oriented Paradigms for Modelling Vascular\ud Tumour Growth: a Case Study

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    Motivated by a family of related hybrid multiscale models, we have built an object-oriented framework for developing and implementing multiscale models of vascular tumour growth. The models are implemented in our framework as a case study to highlight how object-oriented programming techniques and good object-oriented design may be used effectively to develop hybrid multiscale models of vascular tumour growth. The intention is that this paper will serve as a useful reference for researchers modelling complex biological systems and that these researchers will employ some of the techniques presented herein in their own projects

    The importance of geometry in the corneal micropocket angiogenesis assay

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    The corneal micropocket angiogenesis assay is an experimental protocol for studying vessel network formation, or neovascularization, in vivo. The assay is attractive due to the ease with which the developing vessel network can be observed in the same animal over time. Measurements from the assay have been used in combination with mathematical modeling to gain insights into the mechanisms of angiogenesis. While previous modeling studies have adopted planar domains to represent the assay, the hemispherical shape of the cornea and asymmetric positioning of the angiogenic source can be seen to affect vascular patterning in experimental images. As such, we aim to better understand: i) how the geometry of the assay influences vessel network formation and ii) how to relate observations from planar domains to those in the hemispherical cornea. To do so, we develop a three-dimensional, off-lattice mathematical model of neovascularization in the cornea, using a spatially resolved representation of the assay for the first time. Relative to the detailed model, we predict that the adoption of planar geometries has a noticeable impact on vascular patterning, leading to increased vessel ‘merging’, or anastomosis, in particular when circular geometries are adopted. Significant differences in the dynamics of diffusible aniogenesis simulators are also predicted between different domains. In terms of comparing predictions across domains, the ‘distance of the vascular front to the limbus’ metric is found to have low sensitivity to domain choice, while metrics such as densities of tip cells and vessels and ‘vascularized fraction’ are sensitive to domain choice. Given the widespread adoption and attractive simplicity of planar tissue domains, both in silico and in vitro, the differences identified in the present study should prove useful in relating the results of previous and future theoretical studies of neovascularization to in vivo observations in the cornea

    Can the Use of an External: Internal Ratio During Standardised Small-Sided Games be a Detector of Fatigue in Professional Adolescent Soccer Players?

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    The aim of the investigation was to explore whether the external: internal(E: I) ratio during a standardised small-sided game (SSG) was impacted by fatigue monitoring methods in professional adolescent soccer players. Ten professional male soccer players (Mean ± SD; Age: 19.6 ± 1.4 years) data from seven standardised SSG’s (6v6+GK, 2x4 min, 40 x 35m) were analysed during the study. Total distance (TD):Heart rate exertion (HRe), PlayerLoadTM(PL): HReand Explosive distance (ED): HRewere the E: Iratio’s analysed from the SSG’s. Morning perceived wellness score, using a customised self-report questionnaire (energy levels, sleep and muscle soreness), and Flight time: Contraction time (FT:CT), taken from a counter-movement jump (CMJ) performed prior totraining, were used as markers of fatigue in the study. A Z-score of -1 was considered ‘fatigued’. Mixed-effect linear models revealed a significant effect for perceived wellness Z-score on TD: HRe, PL: HReand ED: HRe, which resulted in a small increase in allE: Iratios. FT: CTZ-score resulted in a non-significant, trivial effect on TD: HRe, PL: HReand ED: HRe. The results suggest E:I ratiosare influenced by subjective fatigue, thus, E: Iratio’s may be a non-invasive tool for fatigue detection. However, caution should be taken when interpreting an increase in E:I ratio, and, therefore, the use of E: Iratio’s as a means for fatigue detection requires further investigation

    Participatory methods in energy system modelling and planning – a review

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    This paper presents a systematic review of participatory methods used in energy system modelling and planning. It draws on a compiled database of fifty-nine studies at a local, regional, and national level detailing analysis on full energy systems down to sectors, modes, and single technologies. The initial aim of the paper is to consolidate and present this growing body of literature, providing a clear understanding of which stakeholder groups have been engaged and what methods have been used to link stakeholder engagement with quantitative analysis. On from this, the progress to date in democratising key decision-making processes is discussed, reflecting on the benefits and challenges of a participatory approach, as well as highlighting gaps within the current body of literature. During the review, two differing spatial levels at subnational (cities, municipalities, or regions) and national scale emerged as separate groups for analysis. A clear distinction between the two groups was the motivation for involving stakeholders. At a subnational level, researchers hoping to build local capacity to bring about real-world change engaged with community representatives, whereas national level studies concerned with generating more impactful energy policy measures involved industry, policymaking, and academic experts. One key finding from the review was that only ten out of the fifty-nine studies reviewed noted some form of collaboration with non-academic stakeholders, and moreover 36% of studies involved just a single interaction with participants. This indicates a lack of progress to date in process democratisation within energy system modelling and planning research

    Systematically reviewing the use of participatory methods in energy system modelling and planning literature

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    This article outlines the systematic review process undertaken to identify what progress has been made on the integration of participatory methods into energy system modelling and planning. As an emergent field that combines technical / social sciences, it presented a couple of interesting challenges. Firstly, the issue of language emerged as there is a wide range of different terms that may be used to refer to both the involvement of stakeholders in research and energy system modelling and planning tools. This required careful consideration of the research questions and search criteria during the initial scoping exercise. On from this, a conceptual framing of what a meaningful stakeholder participation involves was developed to help define the criteria for inclusion in this study and assess the literature to date. Finally, in synthesizing the literature reviewed to provide an overview of the field, several creative data visualizations were produced. * Systematic review process customized to identify literature covering the integration of participatory methods and energy system modelling and planning tools. * Conceptual framework developed to define criteria for inclusion in the compiled database

    Association between Antenatal Vaginal Bleeding and Adverse Perinatal Outcomes in Placenta Accreta Spectrum

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    Background and Objectives: Placenta accreta spectrum (PAS) disorders are placental conditions associated with significant maternal morbidity and mortality. While antenatal vaginal bleeding in the setting of PAS is common, the implications of this on overall outcomes remain unknown. Our primary objective was to identify the implications of antenatal vaginal bleeding in the setting of suspected PAS on both maternal and fetal outcomes. Materials and Methods: We performed a case-control study of patients referred to our PAS center of excellence delivered by cesarean hysterectomy from 2012 to 2022. Subsequently, antenatal vaginal bleeding episodes were quantified, and components of maternal morbidity were assessed. A maternal composite of surgical morbidity was utilized, comprised of blood loss ≥ 2 L, transfusion ≥ 4 units of blood, intensive care unit (ICU) admission, and post-operative length of stay ≥ 4 days. Results: During the time period, 135 cases of confirmed PAS were managed by cesarean hysterectomy. A total of 61/135 (45.2%) had at least one episode of bleeding antenatally, and 36 (59%) of these had two or more bleeding episodes. Increasing episodes of antenatal vaginal bleeding were associated with emergent delivery (p \u3c 0.01), delivery at an earlier gestational age (35 vs. 34 vs. 33 weeks, p \u3c 0.01), and increased composite maternal morbidity (76, 84, and 94%, p = 0.03). Conclusions: Antenatal vaginal bleeding in the setting of PAS is associated with increased emergent deliveries, earlier gestational ages, and maternal composite morbidity. This important antenatal event may aid in not only counseling patients but also in the coordination of multidisciplinary teams caring for these complex patients

    The limitations (and potential) of non-parametric morphology statistics for post-merger identification

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    Non-parametric morphology statistics have been used for decades to classify galaxies into morphological types and identify mergers in an automated way. In this work, we assess how reliably we can identify galaxy post-mergers with non-parametric morphology statistics. Low-redshift (z<0.2), recent (t_post-merger 100 kpc) post-merger galaxies are drawn from the IllustrisTNG100-1 cosmological simulation. Synthetic r-band images of the mergers are generated with SKIRT9 and degraded to various image qualities, adding observational effects such as sky noise and atmospheric blurring. We find that even in perfect quality imaging, the individual non-parametric morphology statistics fail to recover more than 55% of the post-mergers, and that this number decreases precipitously with worsening image qualities. The realistic distributions of galaxy properties in IllustrisTNG allow us to show that merger samples assembled using individual morphology statistics are biased towards low mass, high gas fraction, and high mass ratio. However, combining all of the morphology statistics together using either a linear discriminant analysis or random forest algorithm increases the completeness and purity of the identified merger samples and mitigates bias with various galaxy properties. For example, we show that in imaging similar to that of the 10-year depth of the Legacy Survey of Space and Time (LSST), a random forest can identify 89% of mergers with a false positive rate of 17%. Finally, we conduct a detailed study of the effect of viewing angle on merger observability and find that there may be an upper limit to merger recovery due to the orientation of merger features with respect to the observer.Comment: 32 pages, 21 figures Accepted for publication by MNRA

    Walking the walk; meaningfully engaging people with engineering challenges

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    Barriers to the development of renewable energy generally involve non-technical as well as technical challenges, that are dynamic and context dependent. In the case of opposition to large-scale wind energy and overhead transmission lines for example, existing research reveals a complex and diverse range of conditions that shape public perception. However, conventional engineering practices tend to focus on least cost techno-economic evaluation methods such as cost benefit analysis. Here we use the case study example of Ireland’s North-South interconnector project to demonstrate how a narrow focus on techno- economic analysis resulted in failure to adequately incorporate broader socio-political considerations. It demonstrates that the primarily technocentric worldview, which largely pervades engineering teaching and practices, can cause tensions and inertia, slowing the rate of progress along the low carbon transition. This, we argue, points to the need for a cultural / ethos change in engineering education and practice. Engineers should be encouraged and educated to broaden their perspectives and take a more reflective / pragmatic approach to engineering challenges that embraces the diversity of worldviews within our society. We hypothesise that the clear (and necessary) emphasis within engineering curricula on solving purely technical / mathematical problems may foster a reductionist hubris in engineering practice. To address this, contemporary fit-for-purpose curricula necessitate the inclusion of coursework that considers broader societal complexities, including so-called ‘wicked problems’ such as infrastructure projects, which involve placing engineering solutions in broader societal contexts

    An innovative approach for estimating energy demand and supply to inform local energy transitions

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    A vital first step for regional energy transitions is to develop an understanding of the current energy balance and related carbon dioxide emissions. However, there is a lack of clarity within existing literature on how best to determine a complete regional energy balance including industry, residential, services, agriculture, and transport sectors. This paper identifies four key limitations in the literature: overreliance on simple population-based proportioning, a narrow focus on building energy, subsequent omission of transport energy in the majority of studies and a lack of transparency in a significant number of studies. This paper proposes a novel conceptual framework to address these gaps using a combination of local energy usage indicators and national unit energy consumption statistics. The authors apply this multi-dimensional approach to a rural case study region, carefully examining the range of energy usage indicators in each sector before selecting the most suitable. The results quantitatively demonstrate the value of this approach, with the final energy demand in some sectors varying by as much as double or threefold compared with a population weighting. Focusing on the socio-economic drivers of energy demand in this manner provides useful insights into the local context that defines the energy system

    Cow and herd-level risk factors associated with mobility scores in pasture-based dairy cows

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    peer-reviewedLameness in dairy cows is an area of concern from an economic, environmental and animal welfare point of view. While the potential risk factors associated with suboptimal mobility in non-pasture-based systems are evident throughout the literature, the same information is less abundant for pasture-based systems specifically those coupled with seasonal calving, like those in Ireland. Therefore, the objective of this study was to determine the potential risk factors associated with specific mobility scores (0 = good, 1 = imperfect, 2 = impaired, and 3 = severely impaired mobility) for pasture-based dairy cows. Various cow and herd-level potential risk factors from Irish pasture-based systems were collected and analyzed for their association with suboptimal mobility, whereby a mobility score of 0 refers to cows with optimal mobility and a mobility score ≥ 1 refers to a cow with some form of suboptimal mobility. Combined cow and herd-level statistical models were used to determine the increased or decreased risk for mobility score 1, 2, and 3 (any form of suboptimal mobility) compared to the risk for mobility score 0 (optimal mobility), as the outcome variable and the various potential risk factors at both the cow and herd-level were included as predictor type variables. Cow-level variables included body condition score, milk yield, genetic predicted transmitting ability for ‘lameness’, somatic cell score, calving month and cow breed. Herd-level variables included various environmental and management practices on farm. These analyses have identified several cow-level potential risk factors (including low body condition score, high milk yield, elevated somatic cell count, stage of lactation, calving month, and certain breed types), as well as various herd-level potential risk factors (including the amount of time taken to complete the milking process, claw trimmer training, farm layout factors and foot bathing practices) which are associated with suboptimal mobility. The results of this study should be considered by farm advisors when advising and implementing a cow/herd health program for dairy cows in pasture-based systems
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