Lightweight energy absorbing structures for crashworthy design

PhD ThesisThe application of lightweight composite materials into the rail industry requires a stepwise approach to ensure rail vehicle designs can make optimal use of the inherent properties of each material. Traditionally, materials such as steel and aluminium have been used in railway rolling stock to achieve the energy absorption and structural resistance demanded by European rail standards. Adopting composite materials in primary structural roles requires an innovative design approach which makes the best use of the available space within the rolling stock design such that impact energies and loads are accommodated in a managed and predictable manner. This thesis describes the innovative design of a rail driver’s cab to meet crashworthiness and structural requirements using lightweight, cost-effective composite materials. This takes the application of composite materials in the rail industry beyond the current state-of-the-art and delivers design solutions which are readily applicable across rolling stock categories. An overview of crashworthiness with respect to the rail industry is presented, suitable composite materials for incorporation into rolling stock designs are identified and a methodology to reconfigure and enhance the space available within rail vehicles to meet energy absorption requirements is provided. To realise the application of composite materials, this body of work describes the pioneering application of aluminium honeycomb to deliver unique solutions for rail vehicle energy absorbers, as well as detailing the use of lightweight composite materials to react the structural loads into the cab and carbody. To prove the capability of the design it is supported by finite element analysis and the construction of a full-scale prototype cab which culminated in the successful filing of two patents to protect the intellectual property of the resulting design.The European Commission whose Framework 6 funded project “De-Light” (Contract Number 031483) forms the basis of this work

Total allowable commercial catch review for Queensland spanner crab (Ranina ranina), with data to December 2023

This report was prepared to inform on the total allowable commercial catch (TACC) of spanner crabs in managed area A for the forthcoming two quota years 1 July 2024 to 30 June 2025 and 1 July 2025 to 30 June 2026. The harvest strategy used standardised commercial (sCPUE) and fishery independent survey (sFIS) catch rates from two years, compared against target rates, to calculate TACC. The average 2022–2023 catch rate indicators from two years, standardised using generalised linear models, were: sCPUE = 0.754 kilograms per dilly-net lift and sFIS = 5.913 crab per ground-line. The stock indices were the ratio of the indicators compared to their targets. The calculated stock indices were less than 1, signalling catch rates were below target: sCPUE ratio = 0.546 and sFIS ratio = 0.567. The pooled index was 0.556 (average of the two stock indices). The pooled index means that the fishery was at 56% of its target

Torres Strait Reef Line Fishery: Coral trout (Plectropomus spp.) catch rate analysis, with data to June 2022

Following the 2019 preliminary stock assessment in Hutton et al. 2019, an updated analysis of coral trout (Plectropomus spp.) abundance indices in the Torres Strait Finfish Fishery was conducted using logbook data up to June 2022. The primary goal of this analysis was to identify trends in standardised commercial annual catch weights. A generalised linear model was used to standardise catch weights in kilograms per operation-day. Despite data limitations due to the small size of the fishery, catch rates have remained generally steady over the last decade and appear stable under current fishing pressure

Effectiveness of prosthodontic interventions and survival of remaining teeth in adult patients with shortened dental arches - a systematic review Journal of Dentistry

ObjectivesA systematic review of randomised and non-randomised controlled trials was conducted to evaluate studies of the effectiveness of different tooth replacement strategies in adult patients with shortened dental arches. The objectives of the review were to determine the survival rates of different prosthodontic interventions, the risk of tooth loss with and without prosthodontic interventions, and the impact of different tooth replacement strategies on oral-health related quality of life (OHRQoL).MethodsThe protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO CRD42017064851), and the review was conducted in accordance with the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA).ResultsThe search strategy identified 112 potentially relevant publications; 22 from Medline (OVID), 54 from EMBASE (OVID), 35 from CENTRAL, one from the authors’ knowledge of the subject area, and none from OpenSIGLE. Ten articles were included in this systematic review. Of these, four were analyses of different outcomes from a multicentre randomized controlled trial in Germany, whilst one study was the pilot phase for this trial. Two further randomized controlled trials were included from the United Kingdom and Republic of Ireland. The remaining articles were reports of prospective cohort studies from Denmark and the Netherlands.Conclusionsthere is currently insufficient evidence to recommend one tooth replacement strategy over another in adult patients with reduced dentitions.Clinical significanceThere is a need for further research as there are insufficient numbers of good quality randomised controlled trials currently available. Authors should be encouraged to adhere to CONSORT guidelines for randomized controlled trials, and report findings in such a way that facilitates future meta-analysis.<br/

Selection and ranking of the main beam geometry of a freight wagon for lightweighting

The traditional freight wagons employ I-beam sections as the main load-bearing structures. The primary loads they carry are vertical (from loading units) and axial (from train traction and buffers). Ease of manufacturing has played an important role in the selection of the I-beam for this role. However, with lightweighting increasingly becoming an important design objective, an evaluation needs to be done to assess if there are other existing or new section profiles (geometry) that would carry the same operational loads but are lighter. This paper presents an evaluation of 24 section profiles for their ability to take the operational loads of freight wagons. The profiles are divided into two categories, namely ‘conventional – made by wagon manufacturers (including the I-beam)’ and ‘pre-fabricated’ sections. For ranking purposes, the primary design objectives or key performance indicators were bending stress, associated deflection and buckling load. Subsequently, this was treated as a multi-criteria decision-making process. The loading conditions were applied as prescribed by the EU standard EN 12663-2. To carry out structural analysis, finite element analysis was implemented using ANSYS software. To determine the validity of the finite element analysis results, correlation analysis was done with respect to beam theory. Parameters considered were: maximum stress, deflection, second moment of area, thickness, bending stiffness and flexural rigidity. The paper discusses the impreciseness related to the use of beam theory since the local stiffness of the beam is neglected leading to an inaccurate estimation of the buckling load and the vertical displacement. Even more complicated can be the estimation of the maximum stress to be used for comparison when features such as spot welds are present. The nominal stress values computed by means of Navier equation lead to an inaccurate value of the stress since it neglects the variations in the local stiffness, which can lead to an increase in the bending stress values. The main objective of the paper is the applicability of particular section profiles to the railway field with the aim of lightweighting the main structure. Sections commonly adopted in civil applications have also been investigated to understand the stiffness and strength under railway service loads. The common approach reported in literature so far makes use either of the beam theory1 or topological finite element approach2 to determine the optimised shape under the action of the simplified loading conditions. Although the previous approaches seem to be more general, the assumptions made affect the optimisation process since the stress state differs from that attained under the actual service load in the real structure. In this paper, the use of complex shape cross sections and detailed finite element models allows to take account of the real behaviour in terms of stiffness distribution and local stress effects due to manufacturing features like welds. The structural assessment carried out with the detailed models also allows for the proper comparison among the considered sections. Analysis of the results showed that three out of the 24 section profiles have the highest potential to be fitted as the main load-bearing beams for freight wagons, with the pre-fabricated Z-section being the optimum of the three.Peer reviewe

The roles of school in supporting LGBTQ+ youth: A systematic review and ecological framework for understanding risk for suicide-related thoughts and behaviors

The extant literature on suicide-related thoughts and behaviors (STB) has highlighted increased patterns of risk among specific minoritized populations, including lesbian, gay, bisexual, transgender, questioning, intersex, two spirit, and queer (LGBTQ+) youth. Compared to their heterosexual and cisgender peers, LGBTQ+ youth are at increased risk for having STB. Identity-specific stressors such as homonegativity and anti-queerness are among the unique factors posited to contribute to this risk and inhibit factors that protect against suicide. The school setting has been a focal point for suicide prevention and intervention and may also play a key role in linking students to care; however, schools also hold the potential to provide supports and experiences that may buffer against risk factors for STB in LGBTQ+ students. This systematic literature review presents findings from 44 studies examining school-related correlates of STB in LGBTQ+ students, informing an ecological approach to suicide prevention for school settings. Findings underscore the importance of school context for preventing STB in LGBTQ+ youth. Approaches that prioritize safety and acceptance of LGBTQ+ youth should span multiple layers of a student's ecology, including district and state level policies and school programs and interventions, such as Gender and Sexuality Alliances and universal bullying prevention programs. Beyond their role as a primary access point for behavioral health services, schools offer a unique opportunity to support suicide prevention by combating minority stressors through promoting positive social relationships and a safe community for LGBTQ+ students

DUNDRUM-2: Prospective validation of a structured professional judgment instrument assessing priority for admission from the waiting list for a forensic mental health hospital

<p>Abstract</p> <p>Background</p> <p>The criteria for deciding who should be admitted first from a waiting list to a forensic secure hospital are not necessarily the same as those for assessing need. Criteria were drafted qualitatively and tested in a prospective 'real life' observational study over a 6-month period.</p> <p>Methods</p> <p>A researcher rated all those presented at the weekly referrals meeting using the DUNDRUM-1 triage security scale and the DUNDRUM-2 triage urgency scale. The key outcome measure was whether or not the individual was admitted.</p> <p>Results</p> <p>Inter-rater reliability and internal consistency for the DUNDRUM-2 were acceptable. The DUNDRUM-1 triage security score and the DUNDRUM-2 triage urgency score correlated r = 0.663. At the time of admission, after a mean of 23.9 (SD35.9) days on the waiting list, those admitted had higher scores on the DUNDRUM-2 triage urgency scale than those not admitted, with no significant difference between locations (remand or sentenced prisoners, less secure hospitals) at the time of admission. Those admitted also had higher DUNDRUM-1 triage security scores. At baseline the receiver operating characteristic area under the curve for a combined score was the best predictor of admission while at the time of admission the DUNDRUM-2 triage urgency score had the largest AUC (0.912, 95% CI 0.838 to 0.986).</p> <p>Conclusions</p> <p>The triage urgency items and scale add predictive power to the decision to admit. This is particularly true in maintaining equitability between those referred from different locations.</p

The proliferation of human mucosal-associated invariant T cells requires a MYC-SLC7A5-glycolysis metabolic axis

Mucosal-associated invariant T (MAIT) cells are an abundant population of innate T cells that recognize bacterial ligands and play a key role in host protection against bacterial and viral pathogens. Upon activation, MAIT cells undergo proliferative expansion and increase their production of effector molecules such as cytokines. In this study, we found that both mRNA and protein abundance of the key metabolism regulator and transcription factor MYC was increased in stimulated MAIT cells. Using quantitative mass spectrometry, we identified the activation of two MYC-controlled metabolic pathways, amino acid transport and glycolysis, both of which were necessary for MAIT cell proliferation. Last, we showed that MAIT cells isolated from people with obesity showed decreased MYC mRNA abundance upon activation, which was associated with defective MAIT cell proliferation and functional responses. Collectively, our data uncover the importance of MYC-regulated metabolism for MAIT cell proliferation and provide additional insight into the molecular basis for the functional defects of MAIT cells in obesity. </p

UK national observational cohort study investigating Tolerance of Anti-cancer Systemic Therapy in the Elderly:the TOASTIE study

Objective: The Cancer Aging Research Group (CARG) score was developed to predict severe chemotherapy-induced toxicity risk in older adults; validation studies results have varied. The TOASTIE study sought to evaluate the CARG score prospectively in a chemotherapy-naïve United Kingdom (UK) population.Methods and Analysis: This multicentre, prospective, observational study recruited patients aged ≥65 years commencing first-line chemotherapy for any solid organ malignancy or setting. Baseline demographics and established frailty measures were recorded. Follow-up data including toxicity and hospital admissions were collected retrospectively. Baseline CARG score predictive ability was assessed.Results: 339 patients were recruited from 19 centres; median age 73 years (range 65-92), 51.9% male and 54.9% gastrointestinal primary. At baseline, 85% of patients were ECOG PS 0-1, with median Rockwood Clinical Frailty Scale (CFS) 3 (range 0-8). 314 (92.6%) patients had follow-up data; 69 (22.3%) patients experienced CTCAE grade ≥3 toxicity and 84 (27%) required hospital admission during treatment.Increasing CARG risk groups had increased grade 3 toxicity (low 19.6%, medium 22.2%, high 28.2%) however, this was non-significant with no evidence of robust predictive performance. Predictive performance of CFS and ECOG PS was superior to CARG. Importantly, patient and clinician perceptions of toxicity risk differed significantly.Conclusions: In older UK patients with cancer commencing chemotherapy, baseline frailty was prevalent. CARG score did not robustly discriminate or predict high-grade toxicity risk. ECOG and CFS showed superior, albeit limited, ability to predict and discriminate. This study highlights the need for the development of tools that better predict toxicity in this population