Suchergebnisse

In a simple multivariate normal prediction setting, derivation of a predictive distribution can flow from formal Bayes arguments as well as pivoting arguments. We look at two special cases and show that the classical invariant predictive distribution is based on a pivot whose sampling distribution depends on the parameter – that is, the pivot is not an ancillary statistic. In contrast, a predictive distribution derived by a structural argument is based on a pivot with a parameter free distribution (an ancillary statistic). The classical procedure is formal Bayes for the Jeffreys prior. Our results show that this procedure does not have a structural or fiducial interpretation.

The Cornell Leadership Program at Cornell University, USA, aims to assist talented veterinary students to embark on careers in research, academia, government agencies or industry. Over 400 students have participated since the Program began in 1990 and their subsequent careers have been followed. In this study, five sources of data were analysed: application documents of the participants; audio recordings of interviews with each participant from 2000 to 2007; annual tracking records of alumni after graduating with a veterinary degree; spontaneous comments from alumni about how the Program influenced their career plans; and a list of published scientific papers by alumni. Analysis revealed that about 50 per cent of veterinary graduates were establishing themselves in careers envisaged by the Program, although many of them experienced conflicts between a vocational commitment to clinical practice and a desire to solve problems through research. Many alumni asserted that the Program had influenced their career plans, but they had difficulty in accepting that rigorous scientific training was more important in acquiring research skills than working directly on a veterinary research problem. One career of great appeal to alumni was that of veterinary translational science, in which disease mechanisms are defined through fundamental research. It is concluded from the data that there are three challenging concepts for recently qualified veterinarians aiming to advance the knowledge of animal disease: research careers are satisfying and rewarding for veterinarians; a deep understanding of the chosen field of research is needed; and a high standard of scientific training is required to become an effective veterinary scientist.

Scientific research on 'animal welfare' began because of ethical concerns over the quality of life of animals, and the public looks to animal welfare research for guidance regarding these concerns. The conception of animal welfare used by scientists must relate closely to these ethical concerns if the orientation of the research and the interpretation of the findings is to address them successfully. At least three overlapping ethical concerns are commonly expressed regarding the quality of life of animals: (1) that animals should lead natural lives through the development and use of their natural adaptations and capabilities, (2) that animals should feel well by being free from prolonged and intense fear, pain, and other negative states, and by experiencing normal pleasures, and (3) that animals should function well, in the sense of satisfactory health, growth and normal functioning of physiological and behavioural systems. Various scientists have proposed restricted conceptions of animal welfare that relate to only one or other of these three concerns. Some such conceptions are based on value positions about what is truly important for the quality of life of animals or about the nature of human responsibility for animals in their care. Others are operational claims: (1) that animal welfare research must focus on the functioning of animals because subjective experiences fall outside the realm of scientific enquiry, or (2) that studying the functioning of animals is sufficient because subjective experiences and functioning are closely correlated. We argue that none of these positions provides fully satisfactory guidance for animal welfare research. We suggest instead that ethical concerns about the quality of life of animals can be better captured by recognizing three classes of problems that may arise when the adaptations possessed by an animal do not fully correspond to the challenges posed by its current environment. (1) If animals possess adaptations that no longer serve a significant function in the new ...

Background: Overseas-born people who are ineligible for government-subsidised health care experience barriers to accessing HIV pre-exposure prophylaxis (PrEP) in Australia. This study aimed to assess a program providing free PrEP to overseas-born adults at risk of acquiring HIV. Methods: Medicare-Ineligible Expanded Implementation in Communities (MI-EPIC) was a single-arm, open-label trial of daily tenofovir disoproxil fumarate/emtricitabine as PrEP. Six clinics recruited Medicare-ineligible adults who met HIV risk criteria in New South Wales, Australia. We recorded data on HIV and sexually transmitted infection (STI) diagnoses, and PrEP dispensing from July 2019 to June 2020. PrEP adherence as a medication possession ratio (MPR) was calculated as pills dispensed divided by days. We administered an optional survey on behaviours and attitudes to PrEP and sexual health. Results: The 221 participants (206 men; 93.2%) had a median age of 29 years (IQR 26-34). Participants were mostly born in Asia (53.4%), Latin America or the Caribbean (25.3%), or Europe (10.9%). Adherence was high; 190 participants (86.0%) had an MPR of >60%. Of 121 survey participants, 42 (34.7%) completed the survey in a language other than English. Of participants who had not used PrEP in the 6 months before enrolment (n = 45, 37.2%), the most common reasons were cost (n = 22, 48.9%), and lack of knowledge about accessing PrEP (n = 20, 44.4%). Conclusions: Medicare-ineligible people at risk of HIV demonstrate high adherence when given access to free PrEP and translated information. Increasing PrEP awareness and reducing barriers to accessing PrEP in this high-risk population should be priorities in HIV prevention.

Food security is high on the global policy agenda. Demand for food is increasing as populations grow and gain wealth to purchase more varied and resource-intensive diets. There is increased competition for land, water, energy, and other inputs into food production. Climate change poses challenges to agriculture, particularly in developing countries (1), and many current farming practices damage the environment and are a major source of greenhouse gases (GHG). In an increasingly globalized world, food insecurity in one region can have widespread political and economic ramifications (2).