915 research outputs found
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Malaria ecology, child mortality & fertility.
The broad determinants of fertility are thought to be reasonably well identified by demographers, though the detailed quantitative drivers of fertility levels and changes are less well understood. This paper uses a novel ecological index of malaria transmission to study the effect of child mortality on fertility. We find that temporal variation in the ecology of the disease is well-correlated to mortality, and pernicious malaria conditions lead to higher fertility rates. We then argue that most of this effect occurs through child mortality, and estimate the effect of child mortality changes on fertility. Our findings add to the literature on disease and fertility, and contribute to the suggestive evidence that child mortality reductions have a causal effect on fertility changes
Africa's Lagging Demographic Transition: Evidence from Exogenous Impacts of Malaria Ecology and Agricultural Technology
Much of Africa has not yet gone through a "demographic transition" to reduced mortality and fertility rates. The fact that the continent's countries remain mired in a Malthusian crisis of high mortality, high fertility, and rapid population growth (with an accompanying state of chronic extreme poverty) has been attributed to many factors ranging from the status of women, pro-natalist policies, poverty itself, and social institutions. There remains, however, a large degree of uncertainty among demographers as to the relative importance of these factors on a comparative or historical basis. Moreover, econometric estimation is complicated by endogeneity among fertility and other variables of interest. We attempt to improve estimation (particularly of the effect of the child mortality variable) by deploying exogenous variation in the ecology of malaria transmission and in agricultural productivity through the staggered introduction of Green Revolution, high-yield seed varieties. Results show that child mortality (proxied by infant mortality) is by far the most important factor among those explaining aggregate total fertility rates, followed by farm productivity. Female literacy (or schooling) and aggregate income do not seem to matter as much, comparatively.
Operational expenditure costs for wave energy projects and impacts on financial returns
This paper examines 'availability' and the input metrics of operational expenditure (OPEX) for wave energy projects and reports on a case study which assesses the impact of these inputs on project profit returns. Case study simulations modelled a 75 MW wave energy project at two locations; the west coast of Ireland and the north coast of Portugal. Access and availability with respect to weather windows at both locations are discussed and their impact on energy output and wave farm operations is quantified. The input metrics used to calculate OPEX of wave energy projects are defined as well as the impact of OPEX on project net present value (NPV) and internal rate of return (IRR). Results indicate that access and resultant availability factors have a significant impact on case study results by reducing energy output and correspondingly financial returns. Furthermore, the technology maturity level designated for a project also impacts on availability factors and consequently energy output and NPV. Case study profits proved to be very sensitive to annual OPEX, especially if overhaul and replacement costs were accounted for. As a result of the impact of 'availability' on project profit returns. Feed-in tariffs will need to be tailored to the location in question as well as the device technology maturity level, with case study simulations indicating that high FIT will be required to support early stage WEC projects. (C) 2012 Elsevier Ltd. All rights reserved
Kolab: appropriation & improvisation in mobile tangible collaborative interaction
Current design guidelines for conventional tangible systems suggest that the representational significance of tangible tokens is an important consideration in the design of tangible interaction, especially in collaborative contexts. Such advice might be assumed to imply that nomadic tangible systems that employ improvised tokens are liable to have highly impaired usability. In this paper we describe a proof of concept experiment for Kolab, a nomadic tangible interaction system that permits any surface to be appropriated as a collaborative tabletop, and which affords the use of a wide range of appropriated artifacts as improvised tangibles. We demonstrate an approach for realizing the necessary interaction techniques combining tangibles and hand gestures using a fusion of image and depth sensing. We present the results of a user study showing that while users' choices of artifacts were seen to follow an unexpected pattern, various artifacts were appropriated and improvised as tangibles, and the system was found to be both usable and well able to support user collaboration
Recommended from our members
Africa's Lagging Demographic Transition: Evidence from Exogenous Impacts of Malaria Ecology and Agricultural Technology
Much of Africa has not yet gone through a "demographic transition" to reduced mortality and fertility rates. The fact that the continent's countries remain mired in a Malthusian crisis of high mortality, high fertility, and rapid population growth (with an accompanying state of chronic extreme poverty) has been attributed to many factors ranging from the status of women, pro-natalist policies, poverty itself, and social institutions. There remains, however, a large degree of uncertainty among demographers as to the relative importance of these factors on a comparative or historical basis. Moreover, econometric estimation is complicated by endogeneity among fertility and other variables of interest. We attempt to improve estimation (particularly of the effect of the child mortality variable) by deploying exogenous variation in the ecology of malaria transmission and in agricultural productivity through the staggered introduction of Green Revolution, high-yield seed varieties. Results show that child mortality (proxied by infant mortality) is by far the most important factor among those explaining aggregate total fertility rates, followed by farm productivity. Female literacy (or schooling) and aggregate income do not seem to matter as much, comparatively
Mobilising investors for Blue Growth
The European Union's Blue Growth Strategy is a long term strategy to support sustainable growth in the marine and maritime sectors, aiming to contribute to innovation and economic growth (European Commission, 2012). The EU sees the financial sector as a key partner to bring about transition to sustainable consumption and production. However, knowledge about investment behavior, experience with working with these investors, and ways to engage investors in the Blue Growth sectors is lacking. This paper examines this knowledge gap. It characterizes investors and identifies investor behavior, investors' motives, and conditions and criteria relevant for investors to invest in Blue Growth sectors. The presented results are derived from a literature study on investors and investment behavior, an electronic survey and in-depth interviews. Stereotypical images of private equity bankers or wealthy individuals do not do justice to the diversity of investors involved in the Blue Growth sectors. These sectors are still in development and various risks reduce the willingness to invest. Risk mitigation should be seen as a shared responsibility of entrepreneurs, investors and governments. Government support must go further than financial support for research and development or technological demonstration projects. Proven technologies get stuck in the Valley of Death as investors alone are not willing to take the risk associated with upscaling of promising technologies. Tied in a reciprocal relationship, governments need to attract private investors—their capital, knowledge, and networks—to further grow of the Blue Growth sectors while investors need stable, predictable, and effective government support schemes to mitigate their financial risks
Lessons for conservation management: Monitoring temporal changes in genetic diversity of Cape mountain zebra (Equus zebra zebra)
The Cape mountain zebra (Equus zebra zebra) is a subspecies of mountain zebra endemic to South Africa. The Cape mountain zebra experienced near extinction in the early 1900's and their numbers have since recovered to more than 4,800 individuals. However, there are still threats to their long-term persistence. A previous study reported that Cape mountain zebra had low genetic diversity in three relict populations and that urgent conservation management actions were needed to mitigate the risk of further loss. As these suggestions went largely unheeded, we undertook the present study, fifteen years later to determine the impact of management on genetic diversity in three key populations. Our results show a substantial loss of heterozygosity across the Cape mountain zebra populations studied. The most severe losses occurred at De Hoop Nature Reserve where expected heterozygosity reduced by 22.85% from 0.385 to 0.297. This is alarming, as the De Hoop Nature Reserve was previously identified as the most genetically diverse population owing to its founders originating from two of the three remaining relict stocks. Furthermore, we observed a complete loss of multiple private alleles from all populations, and a related reduction in genetic structure across the subspecies. These losses could lead to inbreeding depression and reduce the evolutionary potential of the Cape mountain zebra. We recommend immediate implementation of evidence-based genetic management and monitoring to prevent further losses, which could jeopardise the long term survival of Cape mountain zebra, especially in the face of habitat and climate change and emerging diseases
Integrated methodologies of economics and socio-economics assessments in ocean renewable energy : private and public perspectives
This paper offers a holistic approach to the evaluation of an ocean renewable energy (ORE) technology type or specific project in order to provide a comprehensive assessment of both narrow economic and broader socio-economic performance. This assessment incorporates methods from three pillars areas: Economic - financial returns and efficient use of resources, Social - employment, social and community cohesion and identity, and Environmental - including the physical environment and pollution. These three pillars are then considered in the broader context of governance. In order to structure this evaluation, a novel parameter space model was created, defined by the three pillars and by the scale of the system under assessment. The scale of the system ranged from individual components of an ORE project; to projects comprising of a number of devices; through to a geographic regions in which multiple farms may be deployed. The parameter space consists of an inner circle representing the boundary of interest for a private investor, or a firm, developing an ORE project. The outer circle is characterised by assessment tools typically employed at the broader stakeholder level including economic, social, and environmental methods that can be employed at local, regional or national scale and which are typically employed to inform policy and decision making regarding ORE. Governance sets the stage within which management occurs. Wider impacts to the firm undertaking the project will take into account “externalities” of the project across the three fields. In this model, key methods identified are mapped onto this parameter space and the connectivity explored. The paper demonstrates that the three pillars are inter-connected and each must be considered in any meaningful assessment of ORE sustainability. An integrated assessment approach has the ability to address both the private and the public aspects of an ORE development,. This analysis provides insights on existing best practice, but also reveals the potential for disconnect between an ORE project’s commercial viability and its contribution to environmental and social goals
Alternative activation of macrophages by filarial nematodes is MyD88-independent
AbstractAlternative macrophage activation is largely defined by IL-4Rα stimulation but the contribution of Toll-like receptor (TLR) signaling to this phenotype is not currently known. We have investigated macrophage activation status under Th2 conditions in the absence of the core TLR adaptor molecule, MyD88. No impairment was observed in the ability of MyD88-deficient bone marrow derived macrophages to produce or express alternative activation markers, including arginase, RELM-α or Ym1, in response to IL-4 treatment in vitro. Further, we observed no difference in the ability of peritoneal exudate cells from nematode implanted wild type (WT) or MyD88-deficient mice to produce arginase or express the alternative activation markers RELM-α or Ym1. Therefore, MyD88 is not a fundamental requirement for Th2-driven macrophage alternative activation, either in vitro or in vivo
Joint declaration on mainstreaming RRI across Horizon Europe
Leading RRI researchers and practitioners, together with policymakers and stakeholder organisations, discussed the state-of-the-art and future perspectives for RRI at the ‘Pathways to Transformation’ conference in June 2019, an event which was extended beyond Brussels, for instance by ca. 330 original tweets and ca. 840 retweets from ca. 160 unique accounts. In the conference, many participants expressed their concern about an uncertain future for RRI in the EC. As a result, numerous large-scale EU-funded RRI projects signed a Joint Declaration, urging the European Commission to make RRI a key objective of the upcoming framework programme, Horizon Europe – a plea to both mainstream the approach across the programme and provide specific resources for strengthening the RRI knowledge base. As the Horizon Europe programme is being forged, it is timely to present the Declaration for a broader audience
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