On the Perturbations of Viscous Rotating Newtonian Fluids

The perturbations of weakly-viscous, barotropic, non-self-gravitating, Newtonian rotating fluids are analyzed via a single partial differential equation. The results are then used to find an expression for the viscosity-induced normal-mode complex eigenfrequency shift, with respect to the case of adiabatic perturbations. However, the effects of viscosity are assumed to have been incorporated in the unperturbed (equilibrium) model. This paper is an extension of the normal-mode formalism developed by Ipser & Lindblom for adiabatic pulsations of purely-rotating perfect fluids. The formulas derived are readily applicable to the perturbations of thin and thick accretion disks. We provide explicit expressions for thin disks, employing results from previous relativistic analyses of adiabatic normal modes of oscillation. In this case, we find that viscosity causes the fundamental p- and g- modes to grow while the fundamental c-mode could have either sign of the damping rate.Comment: Accepted for publication by The Astrophysical Journal. 11 pages, no figure

The R-Mode Oscillations in Relativistic Rotating Stars

The axial mode oscillations are examined for relativistic rotating stars with uniform angular velocity. Using the slow rotation formalism and the Cowling approximation, we have derived the equations governing the r-mode oscillations up to the second order with respect to the rotation. In the lowest order, the allowed range of the frequencies is determined, but corresponding spatial function is arbitrary. The spatial function can be decomposed in non-barotropic region by a set of functions associated with the differential equation of the second-order corrections. The equation however becomes singular in barotropic region, and a single function can be selected to describe the spatial perturbation of the lowest order. The frame dragging effect among the relativistic effects may be significant, as it results in rather broad spectrum of the r-mode frequency unlike in the Newtonian first-order calculation.Comment: 19 pages, 4 figures, AAS LaTeX, Accepted for publication in The Astrophysical Journa

A public opinion survey: is presumed consent the answer to kidney shortage in Hong Kong?

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Speeding up to keep up: exploring the use of AI in the research process.

There is a long history of the science of intelligent machines and its potential to provide scientific insights have been debated since the dawn of AI. In particular, there is renewed interest in the role of AI in research and research policy as an enabler of new methods, processes, management and evaluation which is still relatively under-explored. This empirical paper explores interviews with leading scholars on the potential impact of AI on research practice and culture through deductive, thematic analysis to show the issues affecting academics and universities today. Our interviewees identify positive and negative consequences for research and researchers with respect to collective and individual use. AI is perceived as helpful with respect to information gathering and other narrow tasks, and in support of impact and interdisciplinarity. However, using AI as a way of 'speeding up-to keep up' with bureaucratic and metricised processes, may proliferate negative aspects of academic culture in that the expansion of AI in research should assist and not replace human creativity. Research into the future role of AI in the research process needs to go further to address these challenges, and ask fundamental questions about how AI might assist in providing new tools able to question the values and principles driving institutions and research processes. We argue that to do this an explicit movement of meta-research on the role of AI in research should consider the effects for research and researcher creativity. Anticipatory approaches and engagement of diverse and critical voices at policy level and across disciplines should also be considered

Expert views about missing AI narratives: is there an AI story crisis?

Stories are an important indicator of our vision of the future. In the case of artificial intelligence (AI), dominant stories are polarized between notions of threat and myopic solutionism. The central storytellers-big tech, popular media, and authors of science fiction-represent particular demographics and motivations. Many stories, and storytellers, are missing. This paper details the accounts of missing AI narratives by leading scholars from a range of disciplines interested in AI Futures. Participants focused on the gaps between dominant narratives and the untold stories of the capabilities, issues, and everyday realities of the technology. One participant proposed a "story crisis" in which these narratives compete to shape the public discourse on AI. Our findings indicate that dominant narratives distract and mislead public understandings and conceptions of AI. This suggests a need to pay closer attention to missing AI narratives. It is not simply about telling new stories, it is about listening to existing stories and asking what is wanted from AI. We call for realistic, nuanced, and inclusive stories, working with and for diverse voices, which consider (1) story-teller; (2) genre, and (3) communicative purpose. Such stories can then inspire the next generation of thinkers, technologists, and storytellers

Disciplined Exploration of Emergence Using Multi-Agent Simulation Framework

In recent years the concept of emergence has gained much attention as ICT systems have started exhibiting properties usually associated with complex systems. Although emergence creates many problems for engineering complex ICT systems by introducing undesired behaviour, it also offers many possibilities for advance in the area of adaptive self-organizing systems. However, at the moment the inability to predict and control emergent phenomena prevents us from exploring its full potential or avoiding problems in existing complex systems. Towards this end, this paper proposes a framework for empirical study of complex systems exhibiting emergence. The framework relies on agent-oriented modelling and simulation as a tool for examination of specific manifestations of emergence. The main idea is to use an iterative simulation process in order to build a coarse taxonomy of causal relationships between the micro- and macro layers. In addition to the detailed description of the framework, the paper also discusses the corresponding verification and validation processes as important factor for the success of such a study

Economic impact of growing Phomopsis-resistant lupins

The planting of Phomopsis-resistant lupins will increase net farm income. They will also alter the traditional blend of pastures and cropping, depending on grain and wool prices. In mixed farming areas of Western Australia\u27s southern wheatbelt, they will allow more land to be sown to lupins rather than cereals on farms in which the lack of sheep feed over summer severely restricts wool production. The benefits of Phompsis-resistant lupins arise from a reduction in sheep deaths due to lupinosis, a longer safe grazing period (free from lupinosis) on lupin stubbles, a decrease in the need for supplementary sheep feed over summer, improvements in sheep body weight (and possibly wool growth), and increases in harvested gran yield. Farmers should prepare now for this major shift in farm management

Access to primary care and the route of emergency admission to hospital: retrospective analysis of national hospital administrative data

BACKGROUND: The UK government is pursuing policies to improve primary care access, as many patients visit accident and emergency (A and E) departments after being unable to get suitable general practice appointments. Direct admission to hospital via a general practitioner (GP) averts A and E use, and may reduce total hospital costs. It could also enhance the continuity of information between GPs and hospital doctors, possibly improving healthcare outcomes. OBJECTIVE: To determine whether primary care access is associated with the route of emergency admission-via a GP versus via an A and E department. METHODS: Retrospective analysis of national administrative data from English hospitals for 2011-2012. Adults admitted in an emergency (unscheduled) for ≥1 night via a GP or an A and E department formed the study population. The measure of primary care access-the percentage of patients able to get a general practice appointment on their last attempt-was derived from a large, nationally representative patient survey. Multilevel logistic regression was used to estimate associations, adjusting for patient and admission characteristics. RESULTS: The analysis included 2 322 112 emergency admissions (81.9% via an A and E department). With a 5 unit increase in the percentage of patients able to get a general practice appointment on their last attempt, the adjusted odds of GP admission (vs A and E admission) was estimated to increase by 15% (OR 1.15, 95% CI 1.12 to 1.17). The probability of GP admission if ≥95% of appointment attempts were successful in each general practice was estimated to be 19.6%. This probability reduced to 13.6% when <80% of appointment attempts were successful. This equates to 139 673 fewer GP admissions (456 232 vs 316 559) assuming no change in the total number of admissions. Associations were consistent in direction across geographical regions of England. CONCLUSIONS: Among hospital inpatients admitted as an emergency, patients registered to more accessible general practices were more likely to have been admitted via a GP (vs an A and E department). This furthers evidence suggesting that access to general practice is related to use of emergency hospital services in England. The relative merits of the two admission routes remain unclear

Patient experience of general practice and use of emergency hospital services in England: regression analysis of national cross-sectional time series data.

BACKGROUND: The UK Government has introduced several national policies to improve access to primary care. We examined associations between patient experience of general practice and rates of visits to accident and emergency (A&E) departments and emergency hospital admissions in England. METHODS: The study included 8124 general practices between 2011-2012 and 2013-2014. Outcome measures were annual rates of A&E visits and emergency admissions by general practice population, according to administrative hospital records. Explanatory variables included three patient experience measures from the General Practice Patient Survey: practice-level means of experience of making an appointment, satisfaction with opening hours and overall experience (on 0-100 scales). The main analysis used random-effects Poisson regression for cross-sectional time series. Five sensitivity analyses examined changes in model specification. RESULTS: Mean practice-level rates of A&E visits and emergency admissions increased from 2011-2012 to 2013-2014 (310.3-324.4 and 98.8-102.9 per 1000 patients). Each patient experience measure decreased; for example, mean satisfaction with opening hours was 79.4 in 2011-2012 and 76.6 in 2013-2014. In the adjusted regression analysis, an SD increase in experience of making appointments (equal to 9 points) predicted decreases of 1.8% (95% CI -2.4% to -1.2%) in A&E visit rates and 1.4% (95% CI -1.9% to -0.9%) in admission rates. This equalled 301 174 fewer A&E visits and 74 610 fewer admissions nationally per year. Satisfaction with opening hours and overall experience were not consistently associated with either outcome measure across the main and sensitivity analyses. CONCLUSIONS: Associations between patient experience of general practice and use of emergency hospital services were small or inconsistent. In England, realistic short-term improvements in patient experience of general practice may only have modest effects on A&E visits and emergency admissions