4,321 research outputs found

    Infrared spectra of C2H4 dimer and trimer

    Full text link
    Spectra of ethylene dimers and trimers are studied in the nu11 and (for the dimer) nu9 fundamental band regions of C2H4 (~2990 and 3100 cm-1) using a tunable optical parametric oscillator source to probe a pulsed supersonic slit jet expansion. The deuterated trimer has been observed previously, but this represents the first rotationally resolved spectrum of (C2H4)3. The results support the previously determined cross-shaped (D2d) dimer and barrel-shaped (C3h or C3) trimer structures. However, the dimer spectrum in the nu9 fundamental region of C2H4 is apparently very perturbed and a previous rotational analysis is not well verified.Comment: 21 pages, 4 figure

    The sustainable seafood movement is a Governance concert, with the audience playing a key role

    Full text link
    © 2018 by the authors. Private standards, including ecolabels, have been posed as a governance solution for the global fisheries crisis. The conventional logic is that ecolabels meet consumer demand for certified "sustainable" seafood, with "good" players rewarded with price premiums or market share and "bad" players punished by reduced sales. Empirically, however, in the markets where ecolabeling has taken hold, retailers and brands-rather than consumers-are demanding sustainable sourcing, to build and protect their reputation. The aim of this paper is to devise a more accurate logic for understanding the sustainable seafood movement, using a qualitative literature review and reflection on our previous research. We find that replacing the consumer-driven logic with a retailer/brand-driven logic does not go far enough in making research into the sustainable seafood movement more useful. Governance is a "concert" and cannot be adequately explained through individual actor groups. We propose a new logic going beyond consumer- or retailer/brand-driven models, and call on researchers to build on the partial pictures given by studies on prices and willingness-to-pay, investigating more fully the motivations of actors in the sustainable seafood movement, and considering audience beyond the direct consumption of the product in question

    Health outcomes of only children across the life course: An investigation using Swedish register data

    Get PDF
    Only children (with no full biological siblings) are a growing subgroup in many high-income settings. Previous studies have largely focused on the short-term developmental outcomes of only children, but there is limited evidence on their health outcomes. Using Swedish population register data for cohorts born 1940–75, we compare the health of only children with that of children from multi-child sibling groups, taking into account birth order, family size, and presence of half-siblings. Only children showed lower height and fitness scores, were more likely to be overweight/obese in late adolescence, and experienced higher later-life mortality than those with one or two siblings. However, only children without half-siblings were consistently healthier than those with half-siblings, suggesting that parental disruption confers additional disadvantages. The health disadvantage was attenuated but not fully explained by adjustment for parental characteristics and after using within-family maternal cousin comparison designs

    Using a well-being approach to develop a framework for an integrated socio-economic evaluation of professional fishing

    Get PDF
    © 2017 John Wiley & Sons Ltd The principles of Ecologically Sustainable Development and Ecosystem Based Fisheries Management require that fisheries be managed for social as well as environmental and economic objectives. Comprehensive assessments of the success of fisheries in achieving all three objectives are, however, rare. There are three main barriers to achieving integrated assessments of fisheries. Firstly, disciplinary divides can be considered “too hard” to bridge with inherent conflicts between the predominately empirical and deductive traditions of economics and biophysical sciences and the inductive and interpretative approach of much of the social sciences. Secondly, understanding of the social pillar of sustainability is less well developed. And finally, in-depth analysis of the social aspects of sustainability often involves qualitative analysis and there are practical difficulties in integrating this with largely quantitative economic and ecological assessments. This article explores the social well-being approach as a framework for an integrated evaluation of the social and economic benefits that communities in New South Wales, Australia, receive from professional fish harvesting. Using a review of existing literature and qualitative interviews with more than 160 people associated with the fishing industry the project was able to identify seven key domains of community well-being to which the industry contributes. Identification of these domains provided a framework through which industry contributions could be further explored, through quantitative surveys and economic analysis. This framework enabled successful integration of social and economic, and both qualitative and quantitative information in a manner that enabled a comprehensive assessment of the value of the fishery

    Maximising community wellbeing: Assessing the threats to the benefits communities derive from the marine estate

    Get PDF
    © 2018 The coastal and marine environment is often managed according to the principles of sustainable development, which include environmental, economic, and social dimensions. While each are equally important, social sustainability receives a lower priority in both policy and research. Methodologies for assessing social sustainability are less developed than for environmental and economic sustainability, and there is a lack of data on the social aspects of sustainable development (such as social equity), which constitutes a barrier to understanding social considerations and integrating them into natural resource management. This paper explores a threat and risk assessment to the marine estate in New South Wales, Australia, which identified and categorised both the benefits that communities gain from the marine estate and the threats to those benefits. A broad range of benefits were identified including participation (e.g., socialising and sense of community), enjoyment (e.g., enjoying the biodiversity and beauty), cultural heritage and use, intrinsic and bequest values, the viability of businesses, and direct economic values. Threats to community benefits were categorised as resource use conflict, environmental, governance, public safety, critical knowledge gaps and lack of access. An integrated threat and risk assessment approach found that the priority threats to community benefits were environmental threats (e.g., water pollution), critical knowledge gaps (e.g., inadequate social and economic information), governance (e.g., lack of compliance), resource-use conflict (e.g., anti-social behaviour), and lack of access (e.g., loss of fishing access). Threat and risk assessment is an evidence-based tool that is useful for marine planning because it provides a structured approach to incorporating multiple types of knowledge and enables limited resources to be targeted to the threats identified as being most important to address

    On Exactness Of The Supersymmetric WKB Approximation Scheme

    Full text link
    Exactness of the lowest order supersymmetric WKB (SWKB) quantization condition x1x2Eω2(x)dx=nπ\int^{x_2}_{x_1} \sqrt{E-\omega^2(x)} dx = n \hbar \pi, for certain potentials, is examined, using complex integration technique. Comparison of the above scheme with a similar, but {\it exact} quantization condition, cp(x,E)dx=2πn\oint_c p(x,E) dx = 2\pi n \hbar, originating from the quantum Hamilton-Jacobi formalism reveals that, the locations and the residues of the poles that contribute to these integrals match identically, for both of these cases. As these poles completely determine the eigenvalues in these two cases, the exactness of the SWKB for these potentials is accounted for. Three non-exact cases are also analysed; the origin of this non-exactness is shown to be due the presence of additional singularities in Eω2(x)\sqrt{E-\omega^2(x)}, like branch cuts in the xx-plane.Comment: 11 pages, latex, 1 figure available on reques

    Properties of implanted and CVD incorporated nitrogen-vacancy centers: preferential charge state and preferential orientation

    Get PDF
    The combination of the long electron state spin coherence time and the optical coupling of the ground electronic states to an excited state manifold makes the nitrogen-vacancy (NV) center in diamond an attractive candidate for quantum information processing. To date the best spin and optical properties have been found in centers deep within the diamond crystal. For useful devices it will be necessary to engineer NVs with similar properties close to the diamond surface. We report on properties including charge state control and preferential orientation for near surface NVs formed either in CVD growth or through implantation and annealing
    corecore