ON THE DYNAMICS OF COMMERCIAL FISHING AND PARAMETER IDENTIFICATION

This paper has two main objectives. The first is to develop a dynamic model of commercial fisheries different from most existing models that assume optimizing behavior. The industry is assumed to have a well-defined index of performance. Based upon this index, the decision to invest or not is made. We do not, however, assume that the industry or firm is efficient or optimal in its operations. The second is that a new approach of fitting model dynamics to time series data is employed to simultaneously estimate the poorly known initial conditions and parameters of nonlinear fisheries dynamics. The approach is a data assimilation technique known as the variational adjoint method. Estimation of the poorly known initial conditions is one of the attractive features of the variational adjoint method.Resource /Energy Economics and Policy,

Continuous harvesting costs in sole-owner fisheries with increasing marginal returns

We develop a bioeconomic model to analyze a sole-owner fishery with fixed costs as well as a continuous cost function for the generalized Cobb-Douglas production function with increasing marginal returns to effort level. On the basis of data from the North Sea herring fishery, we analyze the consequences of the combined effects of increasing marginal returns and fixed costs. We find that regardless of the magnitude of the fixed costs, cyclical policies can be optimal instead of the optimal steady state equilibrium advocated in much of the existing literature. We also show that the risk of stock collapse increases significantly with increasing fixed costs as this implies higher period cycles which is a quite counterintuitive result as higher costs usually are considered to have a conservative effect on resources.Bioeconomic modelling; Stock collapse; Fixed costs; Pulse fishing; Cyclical dynamics; Increasing marginal returns

How do religious norms diffuse? Institutional translation and international change in a post-secular world society

This article draws from Habermasian post-secular theory to broaden the scope of Constructivist research on norm dynamics beyond its current Western-centric focus. In an increasingly post-secular world society, we conceptualize the mechanism of institutional translation to explain processes of norm diffusion whereby culturally situated ‘thick’ norms acquire a ‘thinner’ ethical status via a dialogical process of normative contestation across diverse ethical perspectives. Institutional translation differs from, but also complements, mechanisms of norm diffusion, such as persuasion and localization, by illustrating how norms conceived and promoted by non-Western religious-based actors can acquire global legitimacy within the institutions of the international liberal order. The article investigates the explanatory value of this framework through an empirical analysis of two contrasting cases of norm promotion by the Organization of Islamic Conference at the United Nations. The first case considers the global diffusion of the norm of dialogue of civilizations as an example of successful institutional translation. The second case illustrates the failed diffusion of the norm against th

Pain trajectory and exercise-induced pain flares during 8 weeks of neuromuscular exercise in individuals with knee and hip pain

OBJECTIVE: Patients considering or engaged in exercise as treatment may expect or experience transient increases in joint pain, causing fear of exercise and influencing compliance. This study investigated the pain trajectory during an 8-week neuromuscular exercise (NEMEX) program together with acute exercise-induced pain flares in persons with knee or hip pain.DESIGN: Individuals above 35 years self-reporting persistent knee or hip pain for the past 3 months were offered 8 weeks of supervised NEMEX, performed in groups twice weekly. The program consisted of 11 exercises focusing on joint stability and neuromuscular control. Participants self-reported joint pain on a 0-10 numerical rating scale (NRS) at baseline and 8-weeks follow-up. NRS pain ratings were also collected before and immediately after every attended exercise session.RESULTS: Joint pain was reduced from baseline (NRS 3.6; 95% CI 3.2-4.1) to 8-weeks follow-up (2.6; 95% CI 2.1-3.1), (P &lt; 0.01). Pain decreased 0.04 NRS (95% CI 0.02-0.05, P &lt; 0.01) on average per exercise session and pre- to post-exercise pain decreased 0.04 NRS (95% CI 0.03-0.05, P &lt; 0.01) on average per session, approaching no acute exercise-induced pain in the last weeks.CONCLUSION: This study found a clear decrease in size of acute exercise-induced pain flares with increasing number of exercise sessions. In parallel, pain ratings decreased over the 8 weeks exercise period. Our findings provide helpful information for clinicians, which can be used to educate and balance patient expectation when starting supervised neuromuscular exercise.</p

Off-World Mental Health:Considerations for the Design of Well-being-Supportive Technologies for Deep Space Exploration

During future long-duration space exploration missions, humans will be exposed to combinations of extreme physical, psychological, and interpersonal demands. These demands create risks for the safety, performance, health, and well-being of both individuals and crew. The communication latency in deep space means that explorers will increasingly have to operate independently and take responsibility for their own self-care and self-management. At present, several research programs are focused on developing and testing digital technologies and countermeasures that support the effective functioning of deep space crews. Although promising, these initiatives have been stimulated mostly by technological opportunity rather than cogent theory. In this perspective, we argue that digital technologies developed for spaceflight should be informed by well-being–supportive design principles and be cognizant of broader conversations around the development and use of digital health applications, especially pertaining to issues of autonomy, privacy, and trust. These issues are important for designing potentially mission-critical health technologies and may be determining factors in the safe and successful completion of future off-world endeavors.publishedVersio

Dealing with disaffection: The influence of work-based learning on 14–16-year-old students’ attitudes to school

Abstract Background: Recent developments in policy concerned with raising achievement in schools have given rise to work-based learning as a mechanism for dealing with disaffection. Alongside this redress is the potential for promoting alternative pathways into further education and/or employment. This paper looks at the impact of a work-based learning programme on engagement/re-engagement for disaffected 14–16-year-olds. Drawing on data collected in a small borough in the north of England, it examines attitudes to learning in school and a vocational learning environment. Methods: Teachers’ and tutors’ attitudinal scoring of disaffected students was collected in school and a work-based learning provider, and interviews were conducted with a smaller sample of the students. Results: The retention of a strong school connection is identified as crucial in improving attitude to learning in disaffected students, while attitude and engagement is shown to be heavily interrelated. Students who solely attend a work-based learning provider are seen to further dissociate from school. Conclusions: This study explores the relationship between engagement and attitude to learning in disaffected 14-16-year-olds. Vocational learning is seen to be highly engaging and promotes an overall improvement in general attitude to learning. In relation to school, however, there is strong evidence of reinforced negative attitudes and further disaffection when students are fully removed from this environment. Thus, the most potent recipe for dealing with disaffection in this research is shown to be a mixture of environments where a connection with school is retained