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71.
72.
Health economics is a relatively new discipline, though its antecedents can be traced back to William Petty FRS (1623–1687). In high-income countries, the academic discipline and scientific literature have grown rapidly since the 1960s. In low- and middle-income countries, the growth of health economics has been strongly influenced by trends in health policy, especially among the international and bilateral agencies involved in supporting health sector development. Valuable and influential research has been done in areas such as cost–benefit and cost-effectiveness analysis, financing of healthcare, healthcare provision, and health systems analysis, but there has been insufficient questioning of the relevance of theories and policy recommendations in the rich world literature to the circumstances of poorer countries. Characteristics such as a country''s economic structure, strength of political and social institutions, management capacity, and dependence on external agencies, mean that theories and models cannot necessarily be transferred between settings. Recent innovations in the health economics literature on low- and middle-income countries indicate how health economics can be shaped to provide more relevant advice for policy. For this to be taken further, it is critical that such countries develop stronger capacity for health economics within their universities and research institutes, with greater local commitment of funding. 相似文献
73.
R. J. Petrell K. Mazhari Tabrizi P. J. Harrison L. D. Druehl 《Journal of applied phycology》1993,5(1):1-14
The technical and economical feasibility of farmingLaminaria saccharina for a food base product near a salmon sea cage farm was evaluated. Suitability of kelp for nutrient removal was also analyzed. A computer model of a conceptualized system was developed in order to make the assessments. Kelp growth was modelled as a linear function of temperature and background dissolved inorganic nitrogen concentration, and it was partially experimentally validated. Based on model simulations, aLaminaria farm containing 10,60 m ropes on each end of a salmon sea cage farm is fertilized by the salmon farm and yields annually 1600 kg of dried kelp. The payback period for the initial investment of $61 × 103 is 6 years after which an annual net profit of 20 × 103 Canadian dollars ($16.68 × 103 US) can be achieved. The net present worth of the kelp farm was positive for a rate of return up to 25%. Kelp production on multiple salmon farms or at a higher kelp density could increase the overall revenue.The kelp farm does not appreciably affect background nutrient or oxygen levels. With a few modifications in the model,Nereocystis andMacrocystis farming can be substituted and evaluated for feasibility and nutrient removal efficiency. 相似文献
74.
Danica Mijovi?-Prelec Draz?en Prelec 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1538):227-240
Self-deception has long been the subject of speculation and controversy in psychology, evolutionary biology and philosophy. According to an influential ‘deflationary’ view, the concept is an over-interpretation of what is in reality an instance of motivationally biased judgement. The opposite view takes the interpersonal deception analogy seriously, and holds that some part of the self actively manipulates information so as to mislead the other part. Building on an earlier self-signalling model of Bodner and Prelec, we present a game-theoretic model of self-deception. We propose that two distinct mechanisms collaborate to produce overt expressions of belief: a mechanism responsible for action selection (including verbal statements) and an interpretive mechanism that draws inferences from actions and generates emotional responses consistent with the inferences. The model distinguishes between two modes of self-deception, depending on whether the self-deceived individual regards his own statements as fully credible. The paper concludes with a new experimental study showing that self-deceptive judgements can be reliably and repeatedly elicited with financial incentives in a categorization task, and that the degree of self-deception varies with incentives. The study also finds evidence of the two forms of self-deception. The psychological benefits of self-deception, as measured by confidence, peak at moderate levels. 相似文献
75.
76.
D. R. Bergdahl 《Journal of nematology》1988,20(2):260-265
Bursaphelenchus xylophilus, pinewood nematode (PWN), is the most serious pest of pine forests in Japan, but in North America its role in pine wilt disease is still being studied. The PWN is known to infest many species of Pinus, with P. nigra, P. sylvestris, and P. thunbergii the most susceptible in the eastern United States. Because of its potential, several European countries (Finland, Norway, and Sweden) and Korea have established embargoes against the importation of coniferous wood from regions of the world known to be infested with the PWN. Although the PWN is not considered an economic pest in North American forests, the recent embargoes have established an impact on current forest management practices and an economic impact on North American export trade. 相似文献
77.
Rhodes DJ 《Cytotechnology》1996,20(1-3):291-297
Conclusions Commercial production of pharmaceutical proteins in baculovirus — insect cell systems is already a reality, and has therefore not been discussed in detail here. Cost-efficacy will depend on the productivity of the protein in culture, the dose, and the quantities required. According to the model described here, cost-effective production of baculoviruses for use in agriculture should also be feasible, assuming the commercial availability of a low-cost medium, together with a baculovirus with high productivity in cell culture, which is effective at a field application rate of 1012 PIB ha-1 or lower. All of these criteria appear to be achievable, given fairly modest advances over currently available technology. Given the relatively high fixed costs associated with production of baculoviruses on an agricultural scale in bioreactors however, profitability will depend on the scale of production. A substantial market opportunity (perhaps in the order of 1 million hectares) would be necessary in order to exploit the economies of scale achievable with baculovirus —insect cell production systems. 相似文献
78.
Costs and benefits of cervical screening. II. Is it worthwhile reducing the screening interval from 5 to 3 years? 总被引:1,自引:0,他引:1
A reduction in screening interval from 5 years to 3 years would greatly increase the cost of the programme, but would save few extra lives. The cost per life saved would be around £250 000 at 1995 prices, or around £8000 per life per year saved. There would in addition be human costs for the women screened. The opportunity cost of reducing the interval may be too great, since it is likely that the Health Service would achieve greater health benefits by investing the funds in other health care activities. 相似文献
79.
Continuous bind‐and‐elute protein A capture chromatography: Optimization under process scale column constraints and comparison to batch operation
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Oliver Kaltenbrunner Luis Diaz Xiaochun Hu Michael Shearer 《Biotechnology progress》2016,32(4):938-948
Recently, continuous downstream processing has become a topic of discussion and analysis at conferences while no industrial applications of continuous downstream processing for biopharmaceutical manufacturing have been reported. There is significant potential to increase the productivity of a Protein A capture step by converting the operation to simulated moving bed (SMB) mode. In this mode, shorter columns are operated at higher process flow and corresponding short residence times. The ability to significantly shorten the product residence time during loading without appreciable capacity loss can dramatically increase productivity of the capture step and consequently reduce the amount of Protein A resin required in the process. Previous studies have not considered the physical limitations of how short columns can be packed and the flow rate limitations due to pressure drop of stacked columns. In this study, we are evaluating the process behavior of a continuous Protein A capture column cycling operation under the known pressure drop constraints of a compressible media. The results are compared to the same resin operated under traditional batch operating conditions. We analyze the optimum system design point for a range of feed concentrations, bed heights, and load residence times and determine achievable productivity for any feed concentration and any column bed height. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:938–948, 2016 相似文献
80.
Mackenzie F. Smith Kelly L. Leverett Bart J. Wilson Sarah F. Brosnan 《American journal of primatology》2019,81(4)
Comparative approaches to experimental economics have shed light on the evolution of social decision‐making across a range of primate species, including humans. Here we replicate our previous work looking at six pairs of capuchin monkeys' (Sapajus [Cebus] apella) responses to scenarios requiring both coordination (Assurance Game) and anti‐coordination (Hawk‐Dove Game). This then provides a foundation for assessing their responses to two additional games, one with a scenario of beneficial cooperation with a temptation to defect (Prisoner's Dilemma) and one with an environment requiring changing strategies within short temporal proximity (Alternating Economic Game). We additionally explored the effects of exogenous oxytocin on decision‐making. Oxytocin did not affect decisions in any of our games. Results from the first two games largely replicated our previous findings. Responses to the Prisoner's Dilemma were more varied than was seen in previous games, with pairs respectively cooperating, defecting, and failing to establish stable strategies. Such variability indicates that this game may be a good assay for individual differences in social decision‐making. Finally, capuchins were able to flexibly switch between their previously established strategies within each of the different games, even when the games were presented within the same session, requiring strategy adjustments within short temporal proximity. These results build on earlier findings showing that capuchins can alter decision‐making strategies as the context demands, which is likely essential for decision‐making in naturally occurring contexts. 相似文献