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Policymakers have attempted to preemptively address the concern of ethical issues with the regulation of automated vehicles. Unfortunately, both policymakers and designers of these technologies struggle to articulate ethical issues and their resolution. We propose a framework that engineers and designers of automated technologies can apply that allows them to identify and resolve ethical tensions within the design task. We demonstrate the practicability of the framework to the engineering design process through a human-subject study where engineers applied the framework in a workshop.
The COVID-19 pandemic and subsequent state of public emergency have significantly affected older adults in Canada and worldwide. It is imperative that the gerontological response be efficient and effective. In this statement, the board members of the Canadian Association on Gerontology/L’Association canadienne de gérontologie (CAG/ACG) and the Canadian Journal on Aging/La revue canadienne du vieillissement (CJA/RCV) acknowledge the contributions of CAG/ACG members and CJA/RCV readers. We also profile the complex ways that COVID-19 is affecting older adults, from individual to population levels, and advocate for the adoption of multidisciplinary collaborative teams to bring together different perspectives, areas of expertise, and methods of evaluation in the COVID-19 response.
The identification of natural bioactive compounds which can prevent the post-weaning growth check and enhance gastrointestinal health in the absence of in-feed medications is an urgent priority for the swine industry. The objective of this experiment was to determine the effects of increasing dietary inclusion levels of laminarin in the first 14 d post-weaning on pig growth performance and weaning associated intestinal dysfunction. At weaning, ninety-six pigs (8·4 (sd 1·09) kg) (meatline boars × (large white × landrace sows)) were blocked by live weight, litter and sex and randomly assigned to: (1) basal diet; (2) basal + 100 parts per million (ppm) laminarin; (3) basal + 200 ppm laminarin and (4) basal + 300 ppm laminarin (three pigs/pen). The appropriate quantity of a laminarin-rich extract (65 % laminarin) was added to the basal diet to achieve the above dietary inclusion levels of laminarin. After 14 d of supplementation, eight pigs from the basal group and the best-performing laminarin group were euthanised for sample collection. The 300 ppm laminarin group was selected as this group had higher ADFI compared with all other groups and higher ADG than the basal group (P < 0·05). Laminarin supplementation increased villus height in the duodenum and jejunum (P < 0·05). Laminarin supplementation increased the expression of SLC2A8/GLUT8 in the duodenum, SLC2A2/GLUT2, SLC2A7/GLUT7, SLC15A1/PEPT1 and FABP2 in the jejunum and SLC16A1/MCT1 in the colon. Laminarin supplementation reduced Enterobacteriaceae numbers in the caecum (P < 0·05) and increased lactobacilli numbers (P < 0·05), total volatile fatty acid concentrations and the molar proportions of butyrate (P < 0·01) in the colon. In conclusion, 300 ppm laminarin from a laminarin-rich extract has potential, as a dietary supplement, to improve performance and prevent post-weaning intestinal dysfunction.
Peripherally inserted central catheters (PICCs) are a mainstay of nonpermanent vascular access devices. In this study, we assessed patients displaying anaphylaxis or anaphylactoid reactions to the PowerPICC SOLO and Groshong PICC (Bard Access Systems) using the Sherlock tip locating system (TLS).
Patients from 2 tertiary-care hospitals were systematically monitored over 4 years for adverse events following the insertion of a PICC using the Sherlock TLS. Insertion data were also collected using the BioFlo PICC (Angiodynamics)from a third hospital site and from The Ottawa Hospital over 4 years as an additional comparator. Three definitions of anaphylaxis and anaphylactoid reactions were utilized, and the Cohen κ was used to assess interrater agreement. Analysis of reactions among the patient cohorts was performed using the χ2 test with Yates correction or the Fisher exact test as appropriate.
Among 8,257 insertions using the TLS PICCs, 37 potential reactions (0.45%) were recorded. Using specific definitions for anaphylaxis or anaphylactoid reactions, 54.1%–91.9% met criteria. Comparator populations using data from Calgary (n = 491) and Ottawa (n = 7,889) using the BioFlo PICC insertion found no reactions. Anaphylactic or anaphylactoid reactions were significantly associated with the PowerPICC SOLO and Groshong PICC with the TLS compared to the BioFlo PICC (P < .0001) across all definitions. The largest subset of patients experiencing adverse reactions had cystic fibrosis (CF) (n = 4, 10.8%).
Our study results demonstrate significant adverse events associated with the PowerPICC SOLO and Groshong PICC using the Sherlock TLS inserted across a range of patient populations. The incidence rate of anaphylaxis or anaphylactoid reactions in the CF population at our center is significantly higher than in non-CF patients (P < .001).
Rapid shallow granular flows over inclined planes are often seen in nature in the form of avalanches, landslides and pyroclastic flows. In these situations the flow develops an inversely graded (large at the top) particle-size distribution perpendicular to the plane. As the surface velocity of such flows is larger than the mean velocity, the larger material is transported to the flow front. This causes size segregation in the downstream direction, resulting in a flow front composed of large particles. Since the large particles are often more frictional than the small, the mobility of the flow front is reduced, resulting in a so-called bulbous head. This study focuses on the formation and evolution of this bulbous head, which we show to emerge in both a depth-averaged continuum framework and discrete particle simulations. Furthermore, our numerical solutions of the continuum model converge to a travelling wave solution, which allows for a very efficient computation of the long-time behaviour of the flow. We use small-scale periodic discrete particle simulations to calibrate (close) our continuum framework, and validate the simple one-dimensional (1-D) model with full-scale 3-D discrete particle simulations. The comparison shows that there are conditions under which the model works surprisingly well given the strong approximations made; for example, instantaneous vertical segregation.
The Association of Polar Early Career Scientists (APECS) is an important legacy of the International Polar Year (IPY). APECS continues to foster engagement in education, outreach and communication (EOC) activities relating to the polar regions and provide training for early career researchers (ECRs). We highlight opportunities for training, leadership and skills development, such as the annual Polar Weeks and Antarctica Day celebrations. Participation and engagement in EOC activities actively contributes to career development by enabling ECRs to develop valuable soft skills such as networking, communication and interdisciplinary knowledge. A pilot survey on EOC engagement highlighted that those who organise events also gain leadership skills such as team management. We discuss several factors contributing to the success of APECS in training the next generation of polar leaders. These include the geographical rather than discipline-specific focus of the organisation, utilisation of online resources, including social media, and the strong links with partner organisations. These examples demonstrate how the EOC legacy of IPY has continued due to APECS’ targeted efforts to create EOC opportunities and provide skills and leadership training for ECRs.
Prior research demonstrated that attention-deficit hyperactivity disorder (ADHD) is associated with binge-eating behavior, binge-eating disorder (BED), and bulimia nervosa (BN). The aim of this study was to investigate these associations in an adult twin population, and to determine the extent to which ADHD symptoms and binge-eating behavior share genetic and environmental factors.
We used self-reports of current ADHD symptoms and lifetime binge-eating behavior and associated characteristics from a sample of over 18 000 adult twins aged 20–46 years, from the population-based Swedish Twin Registry. Mixed-effects logistic regression was used to examine the association between ADHD and lifetime binge-eating behavior, BED, and BN. Structural equation modeling was used in 13 773 female twins to determine the relative contribution of genetic and environmental factors to the association between ADHD symptoms and binge-eating behavior in female adult twins.
ADHD symptoms were significantly associated with lifetime binge-eating behavior, BED, and BN. The heritability estimate for current ADHD symptoms was 0.42 [95% confidence interval (CI) 0.41–0.44], and for lifetime binge-eating behavior 0.65 (95% CI 0.54–0.74). The genetic correlation was estimated as 0.35 (95% CI 0.25–0.46) and the covariance between ADHD and binge-eating behavior was primarily explained by genetic factors (91%). Non-shared environmental factors explained the remaining part of the covariance.
The association between adult ADHD symptoms and binge-eating behavior in females is largely explained by shared genetic risk factors.
Relapse is distressingly common after the first episode of psychosis, yet it is poorly understood and difficult to predict. Investigating changes in cognitive function preceding relapse may provide new insights into the underlying mechanism of relapse in psychosis. We hypothesized that relapse in fully remitted first-episode psychosis patients was preceded by working memory deterioration.
Visual memory and verbal working memory were monitored prospectively in a 1-year randomized controlled trial of remitted first-episode psychosis patients assigned to medication continuation (quetiapine 400 mg/day) or discontinuation (placebo). Relapse (recurrence of positive symptoms of psychosis), visual (Visual Patterns Test) and verbal (Letter–Number span test) working memory and stressful life events were assessed monthly.
Remitted first-episode patients (n = 102) participated in the study. Relapsers (n = 53) and non-relapsers (n = 49) had similar baseline demographic and clinical profiles. Logistic regression analyses indicated relapse was associated with visual working memory deterioration 2 months before relapse [odds ratio (OR) 3.07, 95% confidence interval (CI) 1.19–7.92, P = 0.02], more stressful life events 1 month before relapse (OR 2.11, 95% CI 1.20–3.72, P = 0.01) and medication discontinuation (OR 5.52, 95% CI 2.08–14.62, P = 0.001).
Visual working memory deterioration beginning 2 months before relapse in remitted first-episode psychosis patients (not baseline predictor) may reflect early brain dysfunction that heralds a psychotic relapse. The deterioration was found to be unrelated to a worsening of psychotic symptoms preceding relapse. Testable predictors offer insight into the brain processes underlying relapse in psychosis.
The CANGAROO project incorporates two Čerenkov imaging telescopes at Woomera to obtain stereo images of very high-energy gamma-ray (and cosmic-ray) showers. The first stereo observations, with one imaging system, were made in March 1992, and preliminary stereo imaging observations began in July 1992. This paper describes the stereo imaging technique, the sources under investigation, and the indications from the first data sets.
In this paper the Very High Energy (VHE) gamma-ray astronomy program at the University of Adelaide is described. VHE gamma rays with energies above ~5 × 1011eV are observed using the atmospheric Cerenkov technique. Results from the first three years observations at Woomera and the current upgrading of the telecope are described. The CANGAROO project, a collaboration between the University of Adelaide and a number of Japanese institutions, is also introduced.
With the changing distribution of infectious diseases, and an increase in the burden of non-communicable diseases, low- and middle-income countries, including those in Africa, will need to expand their health care capacities to effectively respond to these epidemiological transitions. The interrelated risk factors for chronic infectious and non-communicable diseases and the need for long-term disease management, argue for combined strategies to understand their underlying causes and to design strategies for effective prevention and long-term care. Through multidisciplinary research and implementation partnerships, we advocate an integrated approach for research and healthcare for chronic diseases in Africa.
Preterm birth may be spontaneous or medically indicated for maternal or fetal reasons. Around 20–25% of preterm births (PTB) follow preterm premature rupture of the membranes (PPROM), however the cause of preterm labour is often unknown. It may represent early maturation and activation of the normal labour process or it may be precipitated by pathological causes. The normal process of labour has a diurnal variation with more deliveries occurring at night. Evidence demonstrating that the diurnal variation persists in preterm deliveries suggest that at least a proportion are due to early maturation of the normal process and the logical assumption is that these may be amenable to prevention or effective treatment. Whatever the cause of preterm delivery, there appears to be a common pathway resulting in activation of inflammatory processes. It is important to distinguish the physiological and pathological causes of preterm labour and not to assume that all inflammation is pathological. The distinction is clinically important since pathological causes may be associated with an adverse intrauterine environment, which would be a contraindication to delaying delivery.
Engineered remediation technologies such as denitrifying bioreactors target single contaminants along a nutrient transfer continuum. However, mixed contaminant discharges to a water body are more common from agricultural systems. Indeed, evidence presented herein indicates that pollution swapping within denitrifying bioreactor systems adds to such deleterious discharges. The present paper proposes a more holistic approach to contaminant remediation on farms, moving from the use of ‘denitrifying bioreactors’ to the concept of a ‘permeable reactive interceptor’ (PRI). Besides management changes, a PRI should contain additional remediation cells for specific contaminants in the form of solutes, particles or gases. Balance equations and case studies representing different geographic areas are presented and used to create weighting factors. Results showed that national legislation with respect to water and gaseous emissions will inform the eventual PRI design. As it will be expensive to monitor a system continuously in a holistic manner, it is suggested that developments in the field of molecular microbial ecology are essential to provide further insight in terms of element dynamics and the environmental controls on biotransformation and retention processes within PRIs. In turn, microbial and molecular fingerprinting could be used as an in-situ cost-effective tool to assess nutrient and gas balances during the operational phases of a PRI.
Information on the burden of hepatitis C virus (HCV) disease is needed to inform policy decisions on primary and secondary prevention. Specimen-based laboratory data (1989–2004) were converted to person-based data and combined with notification data (2004–2009) to describe the burden of HCV infection in Ireland. More than 10 000 people were confirmed as HCV infected in 1989–2004, with the numbers peaking in 2000. The predominant genotypes were 1 (55%) and 3 (39%). Drug use was the most likely risk factor in 80%, with receipt of blood or blood products in 16%. It is estimated that 20 000–50 000 people in Ireland are chronically infected with HCV, a population prevalence of 0·5–1·2%, which is similar to other countries in Northern Europe. This is the first published estimate of the number of chronic HCV infections in Ireland. These data will be of value in health service planning and will contribute to the understanding of HCV infection in Europe.
We investigated an international outbreak of Salmonella Agona with a distinct PFGE pattern associated with an Irish Food company (company X) producing pre-cooked meat products sold in various food outlet chains in Europe. The outbreak was first detected in Ireland. We undertook national and international case-finding, food traceback and microbiological investigation of human, food and environmental samples. We undertook a matched case-control study on Irish cases. In total, 163 cases in seven European countries were laboratory-confirmed. Consumption of food from food outlet chains supplied by company X was significantly associated with being a confirmed case (mOR 18·3, 95% CI 2·2–149·2) in the case-control study. The outbreak strain was isolated from the company's pre-cooked meat products and production premises. Sufficient evidence was gathered to infer the vehicles of infection and sources of the outbreak and to justify the control measures taken, which were plant closure and food recall.
To determine the frequency of cholesteatoma in a population of patients with chronic suppurative otitis media, and to determine whether this frequency is affected by ethnicity.
The study included 6005 patients with chronic suppurative otitis media seen during the course of 30 charitable surgical ‘ear camps’ in Nepal.
Main outcome measures:
Proportion of patients with each subtype of disease, and their ethnicity. A secondary outcome measure was concordance of surname with Nepalese ethnic affiliation.
A total of 762 patients were grouped as being of Tibeto-Mongolian origin, and 4875 as Indo-Caucasian. The rate of chronic suppurative otitis media with cholesteatoma, expressed as a proportion of the rate of all chronic suppurative otitis media subtypes, was 17.8 per cent in Tibeto-Mongolian patients and 18.6 per cent in Indo-Caucasian patients (p > 0.05). The effect of other risk factors (i.e. age, gender and geographical district) on disease distribution was also non-significant. Analysis of secondary outcome measures indicated that patients' surnames were a reliable predictor of ethnicity in this Nepalese population.
There is almost complete concordance in proportions of patients with significant genetic, cultural, and even geographical heterogeneity, suggesting that, in Nepal, the aetiology of cholesteatoma owes little to these factors.