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Abstract Slow strain rate tensile testing was conducted on electrodeposited copper, which is a candidate coating material for used nuclear fuel containers. Embrittlement was observed in electrodeposited copper containing 26.4 ± 1.0 ppm hydrogen, with a strain rate sensitivity such that the embrittlement was exacerbated at lower strain rate (5 × 10−7 s−1). Tensile tests conducted at 100° and 200 °C also intensified embrittlement when compared with tests conducted at room temperature. In contrast, electrodeposited copper containing only 5.25 ± 0.97 ppm hydrogen exhibited ductile behavior at all tested strain rates and temperatures. These findings suggest that a previously unexplained slow strain rate hydrogen embrittlement can operate in electrodeposited copper provided that the hydrogen concentration is sufficiently high. Further analyses revealed that the deformation of embrittled copper is achieved by the formation of internal microcracks which coalesce at the point of failure.

The disposal of high-level radioactive waste (HLW) and spent nuclear fuel (SF) presents a unique challenge for the prediction of the long-term performance of corrodible structures since the HLW/SF canisters are expected, in some cases, to have lifetimes of one million years or longer. Various empirical and deterministic models have been developed over the past 45 years for making predictions of the long-term corrosion behaviour, including models for uniform and localized corrosion, environmentally assisted cracking and microbiologically influenced corrosion. As well as process models focused on specific corrosion mechanisms (described in Part 1 of this review), there is also a need for performance assessment models as part of the overall analysis of the safety of a deep geological repository (DGR). Performance assessment models are often based on simplified or abstracted process models. The manner in which various international waste management programs have predicted the long-term performance of HLW/SF containers with copper, steel, Ni and Ti alloy corrosion barriers is discussed. Performance assessments are repeated periodically during the development and implementation of a DGR, and the corrosion models are constantly updated in light of new mechanistic understanding and/or more information about the deep geological environment. Two examples of how the container performance assessment models evolve over time are also described. Performance assessment models cannot easily be validated, so it is important to build confidence in the long-term predictions using other methods, including natural analogues and large-scale in situ tests and the use of complementary models.

Abstract Background Substance use-related emergency department (ED) visits have increased substantially in North America. Screening for substance use in EDs is recommended; best approaches are unclear. This systematic review synthesizes evidence on diagnostic accuracy of ED screening tools to detect harmful substance use. Methods We included derivation or validation studies, with or without comparator, that included adult (≥ 18 years) ED patients and evaluated screening tools to identify general or specific substance use disorders or harmful use. Our search strategy combined concepts Emergency Department AND Screening AND Substance Use. Trained reviewers assessed title/abstracts and full-text articles for inclusion, extracted data, and assessed risk of bias (QUADAS-2) independently and in duplicate. Reviewers resolved disagreements by discussion. Primary investigators adjudicated if necessary. Heterogeneity precluded meta-analysis. We descriptively summarized results. Results Our search strategy yielded 2696 studies; we included 33. Twenty-one (64%) evaluated a North American population. Fourteen (42%) applied screening among general ED patients. Screening tools were administered by research staff (n = 21), self-administered by patients (n = 10), or non-research healthcare providers (n = 1). Most studies evaluated alcohol use screens (n = 26), most commonly the Alcohol Use Disorders Identification Test (AUDIT; n = 14), Cut down/Annoyed/Guilty/Eye-opener (CAGE; n = 13), and Rapid Alcohol Problems Screen (RAPS/RAPS4/RAPS4-QF; n = 12). Four studies assessing six tools and screening thresholds for alcohol abuse/dependence in North American patients (AUDIT ≥ 8; CAGE ≥ 2; Diagnostic and Statistical Manual of Mental Disorders, 4th Edition [DSM-IV-2] ≥ 1; RAPS ≥ 1; National Institute on Alcohol Abuse and Alcoholism [NIAAA]; Tolerance/Worry/Eye-opener/Amnesia/K-Cut down [TWEAK] ≥ 3) reported both sensitivities and specificities ≥ 83%. Two studies evaluating a single alcohol screening question (SASQ) (When was the last time you had more than X drinks in 1 day?, X = 4 for women; X = 5 for men) reported sensitivities 82–85% and specificities 70–77%. Five evaluated screening tools for general substance abuse/dependence (Relax/Alone/Friends/Family/Trouble [RAFFT] ≥ 3, Drug Abuse Screening Test [DAST] ≥ 4, single drug screening question, Alcohol, Smoking and Substance Involvement Screening Test [ASSIST] ≥ 42/18), reporting sensitivities 64%-90% and specificities 61%-100%. Studies’ risk of bias were mostly high or uncertain. Conclusions Six screening tools demonstrated both sensitivities and specificities ≥ 83% for detecting alcohol abuse/dependence in EDs. Tools with the highest sensitivities (AUDIT ≥ 8; RAPS ≥ 1) and that prioritize simplicity and efficiency (SASQ) should be prioritized.

Computer programs correspond to instructions that tell a computer how to perform a task. Because computers do not understand human languages, programs have to be written in a specialized programming language. Such languages have unique syntax and semantics that on the surface appear quite different from human languages. To foster understanding what a program means, novices need to translate the programming language instructions into a familiar human language. We developed a tutoring system that provides translation activities, from the language Python into plain English, and feedback on student answers. One version of the tutoring system provides open-ended input boxes that students type translations into. A second version instead asks students to generate answers to the translation using drop-down menus. The latter provides more scaffolding but also may encourage shallow behaviors such as guessing and checking. To shed light on how these designs influence learning, we evaluate them with novice programmers. Here, we report on the results of the evaluation and next steps.

The disposal of high-level radioactive waste (HLW) and spent nuclear fuel (SF) presents a unique challenge for the prediction of the long-term performance of corrodible structures since HLW/SF containers are expected, in some cases, to have lifetimes of one million years or longer. Various empirical and deterministic models have been developed over the past 45 years for making predictions of long-term corrosion behaviour, including models for uniform and localised corrosion, environmentally assisted cracking, microbiologically influenced corrosion, and radiation-induced corrosion. More recently, fracture-mechanics-based approaches have been developed to account for joint mechanical–corrosion degradation modes. Regardless of whether empirical or deterministic models are used, it is essential to be able to demonstrate a thorough mechanistic understanding of the corrosion processes involved. In addition to process models focused on specific corrosion mechanisms, there is also a need for performance-assessment models as part of the overall demonstration of the safety of a deep geological repository. Performance-assessment models are discussed in Part 2 of this review.

In this review, we discuss physiological principles that guided the management of a lung transplant for emphysema related to alpha-1-antitrypsin deficiency, where a lung allograft to thoracic cavity size mismatch occurred (donor-to-recipient predicted total lung capacity [pTLC] ratio was 0.89, donor pTLC-to-recipient actual-TLC ratio 0.62). In emphysema, the loss of lung elastic recoil and airway obstruction leads to air trapping and lung hyperinflation. Remodeling of the thoracic cavity (“barrel chest”) develops, which has implications for donor-to-recipient sizing and postoperative management of lung transplantation. We discuss the physiology of a relatively undersized allograft and the impact on chest tube, mechanical ventilation, and respiratory system mechanics management. This case also illustrates how chronic adaptations of the ventilatory pattern to advanced lung diseases are reversible and the chest cavity size can remodel back to normal after lung transplantation.

Summary: Background: Cardiovascular disease incidence and mortality have declined across developed economies and granular up-to-date cost-effectiveness evidence is required for treatments targeting large populations. To assess the health benefits and cost-effectiveness of standard and higher intensity statin therapy in the contemporary UK population 40–70 years old. Methods: A cardiovascular disease microsimulation model, developed using the Cholesterol Treatment Trialists' Collaboration data (117,896 participants; 5 years follow-up), and calibrated in the UK Biobank cohort (501,854 participants; 9 years follow-up), projected risks of myocardial infarction, stroke, coronary revascularization, diabetes, cancer and vascular and nonvascular death for all UK Biobank participants without and with statin treatment. Meta-analyses of trials and cohort studies informed statins’ relative effects on cardiovascular events, incident diabetes, myopathy and rhabdomyolysis. UK healthcare perspective was taken (2020/2021 UK£) with costs per 28 tablets of £1.10 for standard (35%–45% LDL cholesterol (LDL-C) reduction) and £1.68 for higher intensity (≥45% LDL-C reduction) generic statin. Findings: Across categories by sex, age, LDL-C, and cardiovascular disease history/10-year cardiovascular risk, lifetime standard statin increased survival by 0.28–1.85 years (0.20–1.09 quality-adjusted life years (QALYs)), and higher intensity statin by further 0.06–0.40 years (0.03–0.20 QALYs) per person. Standard statin was cost-effective across all categories with incremental cost per QALY from £280 to £8530, with higher intensity statin cost-effective at higher cardiovascular risks and higher LDL-C levels. Stopping statin early reduced benefits and was not cost-effective. Interpretation: Lifetime low-cost statin therapy is cost-effective across all 40–70 years old in UK. Strengthening and widening statin treatment could cost-effectively improve population health. Funding: UK NIHR Health Technology Assessment Programme (17/140/02).

This article describes how two high school algebra teachers and their students focused on examining population trends affected by the creation of a highway though a thriving African American community. The authors adopted Dr. Gholdy Muhammad's (2020) culturally and historically responsive literacy framework to guide their anti-racist mathematics teaching. This genius lens focused their planning, teaching, and reflection on how to support students' meaningful mathematics learning through emotion, criticality, identity, skills, and intellect. The authors describe the three parts of their lesson: (1) humanizing math with emotion and identity; (2) naming racial injustices; and (3) mathematizing population data. The authors' intention in sharing this lesson is to inspire others to create related lessons for their own contexts.

Nature-based solutions (NBS) to flood risk management include natural flood management (NFM) and sustainable drainage systems (SuDS). Still relatively untested in practice, their applications have been separated functionally and spatially. In this article, it is suggested that the emerging approach of managing flood risk holistically over whole catchments is hampered by the persistence of such binaries. Structural, organisational and policy contexts that entrench these divisions are explored through the experiences of flood risk practitioners working in south-west England. Interviews with 11 practitioners working in different aspects of flood risk management within the English Severn and Wye region are analysed. The key findings are grouped into two broad categories: (1) impediments faced by practitioners in implementing NBS, including different spatial NBS understandings, implementation and planning challenges and, monitoring and maintaining NBS; (2) the need for effective NBS governance focused around policy links and community involvement and incentivisation. The analysis draws out three formats of network governance in support of the expansion of cross-sectoral arrangements to plan, implement and monitor NBS flood interventions across extended river catchments in the longer term: regional administration, local lead flood organisation and participant-governed. The focus on the UK, rooted in national contexts, applies conceptually to flood risk governance scenarios in other countries.

Background: The benefit of rapid transport from the scene to definitive in-hospital care versus extended on-scene resuscitation in out-of-Hospital Cardiac Arrest (OHCA) is uncertain. Aim: To assess the use of expedited transport from the scene of OHCA compared with more extended on-scene resuscitation of out-of-hospital cardiac arrest in adults. Methods: A systematic search of the literature was conducted using MEDLINE, Embase, and SCOPUS. Randomised control trials (RCTs) and observational studies were included. Studies reporting transport timing for OHCA patients with outcome data on survival were identified and reviewed. Two investigators assessed studies identified by screening for relevance and assessed bias using the ROBINS-I tool. Studies with non-dichotomous timing data or an absence of comparator group(s) were excluded. Outcomes of interest included survival and favourable neurological outcome. Survival to discharge and favourable neurological outcome were meta-analysed using a random-effects model. Results: Nine studies (eight cohort studies, one RCT) met eligibility criteria and were considered suitable for meta-analysis. On pooled analysis, expedited (or earlier) transfer was not predictive of survival to discharge (odds ratio [OR] 1.16, 95% confidence interval [CI] 0.53 to 2.53, I2 = 99%, p = 0. 65) or favorable neurological outcome (OR 1.06, 95% CI 0.48 to 2.37, I2 = 99%, p = 0.85). The certainty of evidence across studies was assessed as very low with a moderate risk of bias. Region of publication was noted to be a major contributor to the significant heterogeneity observed amongst included studies. Conclusions: There is inconclusive evidence to support or refute the use of expedited transport of refractory OHCA.

Background Lockdowns to reduce the spread of COVID-19 have triggered sharp increases in consumer purchasing behaviour, labelled panic buying. Panic buying has detrimental consequences as it leads to product shortages and disrupts supply chains, forcing retailers to adopt quotas to manage demand. Developing an understanding of the psychological correlates of panic buying can provide targets for public messaging aimed at curbing the behaviour. Objective The study aimed to identify the psychological, individual difference, and demographic factors associated with increased purchasing of non-perishable, cleaning, and hygiene products during COVID-19 lockdowns in Australia. Methods The study used a cross-sectional design (N = 790) with online survey measures administered to community members in Australia during April and May 2020. Data were analysed using structural equation modelling. Results Structural equation models revealed that 1) attitudes, subjective norms, and risk perceptions predicted increased purchasing of non-perishable products; 2) attitudes, risk perceptions, social anxiety sensitivity, and the non-impulsivity facet of trait self-control predicted increased purchasing of hygiene products; and 3) attitudes and risk perceptions predicted increased purchasing of cleaning products. Conclusion Findings provide an understanding of the factors that were associated with panic buying during COVID-19 lockdowns in Australia. Future studies should investigate whether messages designed to influence risk perceptions, attitudes, and subjective norms are effective in curbing the behaviour.

Purpose: Black British minority ethnics (BME) students are nationally underachieving in comparison to their Ethnic Chinese and White peers, showing typically a 16 per cent graduate attainment gap in the UK. Previous research has suggested that the attainment gap could be explained by BME student disengagement, as the students typically commute from family home to University, and they work part time. However, peer-assisted learning (PAL) has been shown to have a positive impact on addressing and resolving student alienation and disengagement. However, a question still remains regarding whether student perceptions hold up to statistical analysis when scrutinised in comparison to similar cohorts without PAL interventions. The paper aims to discuss these issues. Design/methodology/approach: This paper presents the results of a statistical study for two cohorts of students on engineering courses with a disproportionately high representation of BME students. The research method involved a statistical analysis of student records for the two cohorts to ascertain any effect of correlation between: PAL; student ethnicity; and student parental employment on student academic performance and placement attainment. Findings: The results indicate that PAL has no significant impact on the academic performance; however, PAL has a positive impact on the placement/internship attainment for BME students and students from parental households with parents in non-managerial/professional employment. Research limitations/implications: The research limitations are that the cohorts are small, but more equal diverse mix of different social categories than any other courses. However, as the cohorts are less than 30 students, comparing social categories the data sets are small to have absolute confidence in the statistical results of academic performance. Even the "t"-test has its limitations as the subjects are human, and there are multiple personal factors that can impact an individual academic performance; therefore, the data sets are heterostatic. Practical implications: The results highlight that there is need for pedagogy interventions to support--ideally all BME students from all social category to secure placements; BME students who are unable to go on placement to gain supplementary learning that has the same impact on their personal development and learning as placement/internship experience; and White students from managerial/professional family households to engage more in their studies. Social implications: Not addressing and providing appropriate pedagogy interventions, in the wider context not addressing/resolving the BME academic and placement attainment gap, a set of students are being disadvantaged to their peers through no fault of their own, and compounding their academic attainment. As academics we have a duty to provide every opportunity to develop our student attainment, and as student entry is generally homogeneous, all students should attain it. Originality/value: Previous research evaluation of PAL programmes has focused on quantitative students surveys and qualitative semi-structured research interviews with students on their student engagement and learning experience. On the other hand, this paper evaluates the intervention through conducting a quantitative statistical analysis of the student records to evaluate the impact of PAL on a cohort's performance on different social categories (classifications) and compares the results to a cohort of another group with a similar student profile, but without PAL intervention implementation.