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An enigmatic large discoidal fossil from the pennsylvanian of county clare, Ireland
No full textA rare and unusual large solitary discoidal fossil has been discovered on a paving slab quarried from the cyclothems of the Central Clare Group (Kinderscoutian, Pennsylvanian, Carboniferous), western Ireland. The fossil impression consists of a smooth raised inner discoidal area, surrounded by a slightly lower relief outer ring, ca. 130–135 mm in diameter, with eight prominent equidistant ovoid raised nodes towards the outermost margin. The octoradial body plan of this enigmatic specimen suggests a cnidarian connection and, as it is preserved as a positive hyporelief cast, it is tentatively interpreted as the resting trace of a large benthic anemone, which was either partially or fully infaunal. The discoidal fossil is interesting palaeoecologically; it occurs within the well-known Liscannor flag-stone, which consists of thinly bedded, fine-grained sandstone that is extensively covered by prominent, sinuous to meandering, horizontal grazing trails attributed to Psammichnites plummeri. This sedimentary facies likely represents mouth-bar sedimentation on a delta front of a river-dominated delta. The discoidal impression occurs on a portion of the slab where these trace fossils are relatively scarce. Uncertainty surrounds the classification and interpretation of the disc due to its relatively simple morphological form, coupled with a lack of unequivocally diagnostic features — a problem commonly encountered in studies of discoidal fossils from both the Ediacaran and the Phanerozoic</p
Development of hybrid machine learning models for quality assurance and process optimisation of ultrasonic welding and computer numerical control (CNC) machining
No full textData-driven modelling has gained significant interest in the wake of Industry 4.0 as it has scope to create efficient, robust, and sustainable manufacturing systems. Traditionally, physics-based modelling approaches were the sought-after technique as they had demonstrated excellent prediction accuracies. However, as industries are adopting Industry 4.0 technologies, the amount of manufacturing related data is growing exponentially. The abundance of rich data can be transformed into actionable data in the form of predictive models. Furthermore, as a result of the remarkable developments in computing power in recent times, data-driven modelling approaches are becoming practical for many enterprises. Machine learning algorithms are data-driven modelling algorithms which are effective methods of exploiting high dimensional data. It is now feasible for enterprises to develop robust machine learning models by training them on the abundance of manufacturing data. There are various types of machine learning algorithms each with their own advantages and disadvantages. This work investigates how different machine learning algorithms can be combined to mitigate the drawbacks with stand-alone methods in order to create robust hybrid models. To acquire insights into ultrasonic welding (USW) of aluminium 5754 and to determine the suitability of machine learning models for monitoring the USW process, an experimental investigation was conducted. A full factorial design of experiments was performed and both open and closed-loop predictive models were developed using a hybrid genetic algorithm–artificial neural network (GA-ANN) trained on the experimental data. It was found that the closed-loop predictive model, which formulates predictions based on process inputs and process feedback, reduced the prediction error from 13.17% to 7.51%, compared to the open-loop model which uses process inputs only. Therefore, the use of process feedback acquired from integrated sensor data increases the robustness of the predictive model.Investigation of data-driven approaches progressed to optimise a USW process for the joining of a dissimilar composite material pair, i.e., Polyetherketoneketone (PEKK) to epoxy. An ensemble neural network (ENN) was developed whose base learners were hybrid GA-ANNs. The ENNs hyperparameters were optimised through Bayesian optimisation. Once trained, the ENN was exploited to identify the optimal parameter permutation that repeatedly produces the maximum joint strength while also producing a defect free joint. The predictions were subsequently validated through experimentation where the prediction error produced was just 3%.To evaluate the agnostic nature of data-driven approaches, the modelling approach devised to optimise the USW process was applied to a CNC machining process. Initially, a full factorial design of experiments was conducted to acquire insight into the process. ANOVA identified that feed per tooth, cutting speed and depth of cut were significant contributors to surface finish, therefore, all were considered when developing the ENN. Once trained on the experimental data, the ENN was assessed on six distinct scenarios, where the predictions were validated through experimentation. The mean prediction error was just 2.56% where the maximum prediction error was 3.57%.The findings of this thesis enhance the understanding of data-driven modelling of USW and CNC machining processes. Although the manufacturing use cases investigated were USW and CNC machining, the agnostic nature of the modelling approach is relevant to any manufacturing processes that requires process parameter refinement. </p
Decision-making in professional sporting environments: An International survey of experienced performance support staff perspectives
No full textBackground Decision-making is a critical component of performance support staff responsibilities, yet research exploring staff perceptions relating to key facets of decision-making is lacking. Objectives The objectives of this study were to explore perceptions of performance support staff relating to; the importance of decision-making in their role, the value of team decision-making, strategies to enhance decision-making skills, monitoring the process and outcome of decisions, and the obstacles to good decision-making within their working contexts. Methods A mixed-methods approached was used to explore perceptions of decision-making in 191 performance support staff (male = 179, female = 12) working in professional (n = 147) or international (n = 44) sport. Results Performance support staff reported decision-making as extremely important to their role; however only 31% had received formal decision-making education and revealed a lack of people development and a lack of skills and education within their organisations. Most support staff conveyed that team decision-making is a valuable endeavour and augments decision outcomes; yet articulated ineffective teamwork as an obstacle to good decision-making in their environments. Largely, performance support staff reported an absence of organisational strategy and processes and procedures for tracking and making decisions respectively, while only 22% had a consistent reviewing and updating process. When making decisions, performance support staff faced several different cognitive biases and were challenged by the pressure and the time sensitive nature of their environments. Conclusion Performance support staff recognised the importance of decision-making in their roles; yet also identified many obstacles to effective decision-making. The perspectives documented here suggest that performance support staff would likely benefit from undertaking evidence-based training and implementing scientifically informed strategies to enhance decision-making processes within their organisations.</p
Re-constructing the news: an examination of print news media representations of murder-suicides in Ireland
No full textThe representation of the phenomenon of murder-suicide garners multi-faceted constructions. Building on previous international research, this study examines how the print news media construct cases of murder-suicide in Ireland. Using a methodological framework informed by framing theory, ethnographic methods and discourse analysis, it examines coverage in various facets of construction: content, production, and audience reception. Social constructionism is employed as the chief theoretical framework underpinned by five separate yet related theories, the Hierarchy of Influences, Ethical Theory, Framing, Critical Discourse Analysis and Collective Action Framing. Findings show murder-suicides were presented as being rooted in mental health problems, financial debt and indirect victim blaming, which served to reduce perpetrator culpability. A default construction of only reporting the facts that aligned with the story template, and referring to incidents as singular, exceptional, and unexpected, with no connection to broader aspects of gendered violence or the wider social context were also found. Biases in reporting were linked to class and ethnicity and a pattern of othering of marginalised groups, whilst source-strategies failed to challenge the patriarchal system within which the violence occurred. News media professionals’’ sense of duty to the public and to provide a full and frank disclosure of information, outweighed their responsibility to any guide or code of ethics in the context of covering cases of murder-suicide, whilst audience reaction to reporting was met with a defensive attitude towards critiques of this representation. These discursive patterns contributed to an overall explanatory framework which was couched in preferred narratives and root the cause of the events in selective hypotheses which serves to naturalise extreme violence as a response to it.Findings here raise questions on whose interests are best served by this type of coverage and the implications for not only how murder-suicide is constructed but how journalists construct meaning-making through their prism of objectivity. Furthermore, the study reveals that how news media professionals’ perceive their duty to their news organisation supersedes how they perceive their duty to their audience. Their priority was to construct and populate media templates which would fulfil their infotainment role. In the context of an increasingly competitive commercial environment, it is questionable whether there is a desire for principled reflection or unprofitable decisions. Their lack of reflexivity in noting that there may be multiple, and sometimes competing and uncertain, realities to be considered when constructing these cases, was evident. Given that the role of the print news media has been recognised at policy level in Ireland1 , examining their construction of murder-suicides is an important area of inquiry, particularly in relation to how they can re-think and reform their reporting on this issue.</p
Early supported discharge for older adults admitted to hospital after orthopaedic surgery: a systematic review and meta-analysis
No full textBackground Early supported discharge (ESD) aims to link acute and community care, allowing hospital inpatients to return home, continuing to receive the necessary input from healthcare professionals that they would otherwise receive in hospital. Existing literature demonstrates the concept having a reduced length of stay in stroke inpatients and medical older adults. This systematic review aims to explore the totality of evidence for the use of ESD in older adults hospitalised with orthopaedic complaints.Methods A literature search of Cochrane Central Register of Controlled Trials in the Cochrane Library (CENTRAL), EMBASE, CINAHL and MEDLINE in EBSCO was carried out on January 10th, 2024. Randomised controlled trials or quasi-randomised controlled trials were the study designs included. For quality assessment, The Cochrane Risk of Bias Tool 2.0 was used and GRADE was applied to evaluate the certainty of evidence. Acute hospital length of stay was the primary outcome. Secondary outcomes included the numbers of fallers and function. A pooled meta-analysis was conducted using RevMan software 5.4.1.Results Seven studies with a population of older adults post orthopaedic surgery met inclusion criteria, with five studies included in the meta-analysis. Study quality was predominantly of a high risk of bias. Statistically significant effects favouring ESD interventions were only seen in terms of length of stay (FEM, MD = -5.57, 95% CI -7.07 to -4.08, I 2=0%). No statistically significant effects favouring ESD interventions were established in secondary outcomes.Conclusion In the older adult population with orthopaedic complaints, ESD can have a statistically significant impact in reducing hospital length of stay. This review identifies an insufficient existing evidence base to establish the key benefits of ESD for this population group. There is a need for further higher quality research in the area, with standardised interventions and outcome measures used.</p
Sensitivity of cross-sectional compliance to manufacturing tolerances for wind turbine blades
No full textWind turbine blades are complex structures and, despite advancements in analysis techniques, differences persist between predictions of their elastic response and experimental results. This undermines confidence in the ability to reliably design and certify novel blade designs that include self-regulating features like bend– twist coupling. To address these discrepancies, this study investigates the influence of manufacturing tolerances on the compliance properties of blade cross-sections, focusing specifically on a previously disregarded feature: the trailing edge bondline. To conduct this investigation, the validated cross-sectional modelling tools BECAS and VABS are used to demonstrate that even small geometric variations can have significant influence on cross-sectional stiffness properties. The results are further examined and substantiated through the utilisation of 3D finite element models, adopting both shell and solid elements. We reaffirm that an accurate geometric representation of the cross-section is necessary to adequately capture the shear flow within it and assure accurate predictions on cross-sectional stiffness properties, providing updated guidelines for designers in industry.</p
Adenosine metabolism pathway alterations in frontal cortical neurons in schizophrenia
No full textSchizophrenia is a neuropsychiatric illness characterized by altered neurotransmission, in which adenosine, a modulator of glutamate and dopamine, plays a critical role that is relatively unexplored in the human brain. In the present study, postmortem human brain tissue from the anterior cingulate cortex (ACC) of individuals with schizophrenia (n = 20) and sex- and age-matched control subjects without psychiatric illness (n = 20) was obtained from the Bronx–Mount Sinai NIH Brain and Tissue Repository. Enriched populations of ACC pyramidal neurons were isolated using laser microdissection (LMD). The mRNA expression levels of six key adenosine pathway components—adenosine kinase (ADK), equilibrative nucleoside transporters 1 and 2 (ENT1 and ENT2), ectonucleoside triphosphate diphosphohydrolases 1 and 3 (ENTPD1 and ENTPD3), and ecto-5′ -nucleotidase (NT5E)—were quantified using real-time PCR (qPCR) in neurons from these individuals. No significant mRNA expression differences were observed between the schizophrenia and control groups (p > 0.05). However, a significant sex difference was found in ADK mRNA expression, with higher levels in male compared with female subjects (Mann–Whitney U = 86; p 0.05). The observed sex-specific variations and inter?component correlations highlight the value of investigating sex differences in disease and contribute to the molecular basis of schizophrenia’s pathology.</p
Orthopaedic and trauma research in Tanzania: A scoping review
No full textTanzania is disproportionately burdened by musculoskeletal injuries as it faces unique challenges when dealing with trauma care. This scoping review aims to summarize and assess the current state of orthopaedic and trauma research in Tanzania. By identifying key themes, trends, and gaps in the literature, this review seeks to guide future research initiatives catered specifically to the needs of Tanzania’s healthcare system. Utilizing the PRISMA-ScR protocol, OVID Medline, PubMed, and CINAHL databases were searched from inception to June 17, 2023, using keywords such as “Orthopaedics” “Trauma” and “Tanzania”. One hundred and ninety-two eligible studies were included and the Arksey and O’Malley framework for scoping studies was followed. There was a notable growth of relevant publications from 2015 onward, with peaks in growth in the years 2019, 2021, and 2020. The studies employed diverse research methodologies, with cross-sectional (n = 41, 21%) and prospective studies (n = 39, 20%) being the most prevalent, and randomized-controlled trials being the least prevalent methodology, making up eight studies (4.2%). The most common study themes were trauma (n = 101, 52.6%), lower extremity (n = 31, 16%), and spine-related issues (n = 27, 14%). Only three studies looked at work-related injuries (1.6%). Road traffic injuries (RTIs) were the most common mechanism of trauma in 77.0% of the trauma focused studies. Fifty-three percent of the studies were conducted by a majority of Tanzanian authors. This scoping review highlights various trends in orthopaedic and trauma research in Tanzania, with a particular emphasis on road traffic-related injuries. Various gaps are explored, including a lack of research on work-related injuries and a paucity of experimental research. Our findings underline areas where future research is warranted. The future of orthopaedic and trauma care in Tanzania depends on the efforts and collaboration of both local and international stakeholders.</p
Water sorption studies with mesoporous multivariate monoliths based on UiO-66
No full textHierarchical linker thermolysis has been used to enhance the porosity of monolithic UiO-66-based metal-organic frameworks (MOFs) containing 30 wt% 2-aminoterephthalic acid (BDC-NH2) linker. In this multivariate (i.e. mixed-linker) MOF, the thermolabile BDC-NH2 linker decomposed at ∼350 °C, inducing mesopore formation. The nitrogen sorption of these monolithic MOFs was probed, and an increase in gas uptake of more than 200 cm3 g−1 was observed after activation by heating, together with an increase in pore volume and mean pore width, indicating the creation of mesopores. Water sorption studies were conducted on these monoliths to explore their performance in that context. Before heating, monoUiO-66-NH2-30%-B showed maximum water vapour uptake of 61.0 wt%, which exceeded that reported for either parent monolith, while the highly mesoporous monolith (monoUiO-66-NH2-30%-A) had a lower maximum water vapour uptake of 36.2 wt%. This work extends the idea of hierarchical linker thermolysis, which has been applied to powder MOFs, to monolithic MOFs for the first time and supports the theory that it can enhance pore sizes in these materials. It also demonstrates the importance of hydrophilic functional groups (in this case, NH2) for improving water uptake in materials.</p
A cross-sectional study of the relative availability and prominence of shelf space allocated to healthy and unhealthy foods in supermarkets in urban Ireland, by area-level deprivation
No full textBackground Diet-related noncommunicable diseases (NCDs) are a leading cause of ill-health and death across Europe. In Ireland, dietary intakes of saturated fat, free sugar and salt exceed World Health Organization recommendations, and excess consumption follows a social gradient increasing population risk of diet-related NCDs. The retail food environment can influence consumer food choice and subsequent dietary intakes. In high income countries, supermarkets are an increasingly influential actor in consumer food availability, choice, purchase, and subsequent food intake. This study aims to assess the relative availability and prominence of healthy and unhealthy foods in Irish supermarkets, by area-level deprivation. Methods This study used a cross-sectional study design, and applied a validated measure, as described in the INFORMAS Protocol: Food Retail – Food availability in supermarkets. Between October 2021 and February 2022, shelf space (m2 ) (height or depth (cm) × length (cm)) and prominence (visibility), of foods, classified as healthy and unhealthy and represented by a proxy indicator, were collected in supermarkets (n =36) in County Dublin, Ireland. Overall the proportion of mean relative shelf space (m2 ), allocated to healthy and unhealthy foods, and its prominence, by area-level deprivation, and retailer, were determined. We used t-tests and one-way ANOVA to analyse possible differences between the proportion of relative shelf space available to healthy and unhealthy foods, and its prominence, by area-level deprivation and retailer. Results The study found the proportion of shelf space measured allocated to unhealthy food was 68.0% (SD 10.6). Unhealthy foods were more likely to be in areas of high prominence. Overall, there was no statistically significant difference between the proportion of relative shelf space available to unhealthy foods in areas of high and low deprivation. A statistically significant difference in the proportion of relative shelf space allocated to healthy and unhealthy food by area level deprivation was found in one retailer.Conclusion Unhealthy foods had a higher proportion of shelf space and were more prominent than healthy foods in supermarkets in County Dublin, Ireland. The current availability and prominence of foods in supermarkets does not align with Food Based Dietary Guideline recommendations and does not support consumers to make healthier food choices. There is a need for supermarkets in Ireland to improve the availability and prominence of healthy foods to support consumers to make healthier food choices.</p