10,501 research outputs found

    Assessing the contribution of ecosystem services to human wellbeing: A disaggregated study in western Rwanda

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    AbstractLack of attention to social complexity has created a gap between current ecosystem service research and the kind of insights needed to inform ecosystem management in the tropics. To contribute to closing this gap, this study applies a methodology for exploring complex linkages between ecosystem services and human wellbeing. This builds on emerging frameworks for studying multiple dimensions of human wellbeing, drawing on Amartya Sen's capabilities approach to human development. The approach is applied to an empirical case study of three sites adjacent to native tropical forest in western Rwanda. The value of exploring social complexity in ecosystem services research is illustrated through its contribution to understanding a) different types of values; b) disaggregation of people; c) power relations and their influence on trade-offs; d) the importance of multiple land use types in the landscape; and e) changes and their drivers at multiple scales. The analysis reveals that the majority of services valued by forest-adjacent Rwandan inhabitants are not provided by tropical forests but by other habitats. We suggest that more integrated landscape governance may offer synergistic opportunities for conservation and development

    Different forms of the bovine PrP gene have five or six copies of a short, G-C-rich element within the protein-coding exon

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    Current models of the virus-like agents of scrapie and bovine spongiform encephalopathy (BSE) have to take into account that structural changes in a host-encoded protein (PrP protein) exhibit an effect on the time course of these diseases and the survival time of any man or animal exposed to these pathogens. We report here the sequence of different forms of the bovine PrP gene which contain either five or six copies of a short, G-C-rich element which encodes the octapeptide Pro-His-Gly-Gly-Gly-Trp-Gly-Gln or its longer variants Pro-Gln/His-Gly-Gly-Gly-Gly-Trp-Gly-Gln. Out of 12 cattle, we found eight animals homozygous for genes with six copies of the Gly-rich peptide (6:6), while four were heterozygous (6:5). Two confirmed cases of BSE occurred in (6: 6) homozygous animals. Bovine spongiform encephalopathy (BSE) is a transmissible disease (Fraser et al., 1988; Dawson et al., 1990; Barlow & Middleton, 1990) which produces neuropathological lesions in cattle similar to those seen in ovine scrapie (Wells et al., 1987) and the rare human dementias Creutzfeldt-Jakob disease (CJD) and Gerstmann-Str/iussler syndrome (GSS) (Beck & Daniel, 1987). A cellular membrane protein (PrP) has a key role in the transmission and development of these diseases. This protein accumulates in the brain and other tissues during the protracted time course of these diseases and, in a disease-specific, protease-resistant isoform (SAF-PrP), has been purified by subcellular fractionation of scrapie

    Functional assessment for acute stroke trials: properties, analysis, and application

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    A measure of treatment effect is needed to assess the utility of any novel intervention in acute stroke. For a potentially disabling condition such as stroke, outcomes of interest should include some measure of functional recovery. There are many functional outcome assessments that can be used after stroke. In this narrative review, we discuss exemplars of assessments that describe impairment, activity, participation, and quality of life. We will consider the psychometric properties of assessment scales in the context of stroke trials, focusing on validity, reliability, responsiveness, and feasibility. We will consider approaches to the analysis of functional outcome measures, including novel statistical approaches. Finally, we will discuss how advances in audiovisual and information technology could further improve outcome assessment in trials

    Characterization of some products of starch-enzyme digestion

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    A water-jacketed viscosimeter for measuring the rate of liquefaction of starch pastes by diastase has been described;A macro volumetric modification of Hagedorn and Jensen\u27s sugar method, applicable to following the course of amylase action has been developed;A potentiometric method of determining reducing values during amylase action has been developed;The temperature at which the substrate is prepared has been found to affect the rate of beta amylase action. Optimum temperatures for preparation of potato starch for amylase action is 70°, for tapioca 80°, for rice 80° or above, and for corn and wheat starches 85°90°;Methods of separating the flocculent material (precipitate A) and 60 percent alcohol insoluble residue (precipitate B) from beta amylase digestions have been described;The preparations were characterized as to further enzyme hydrolysis, phosphorus and fatty acid content, reducing action against ferricyanide and against copper, and recovery in the starch determination of Denny (14);The measured properties of precipitates A and B tend to show that precipitate A is a portion of precipitate B which is less soluble;Precipitates A and B from cereal and root starches show marked differences. These differences have not as yet been explained

    PDF uncertainties in Higgs production at hadron colliders

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    Using the new schemes provided by the CTEQ and MRST collaborations and by Alekhin, we analyse the uncertainties due to the parton distribution functions (PDFs) on the next-to-leading-order cross sections of the four main production processes of the Standard Model Higgs boson at the LHC and the Tevatron. In the Higgs mass range where the production rates are large enough, the spread in the uncertainties when the three sets of PDFs are compared is of about 15% in all processes and at both colliders. However, within one given set of PDFs, the deviations from the values obtained with the reference sets are much smaller, being of O(5{\cal O}(5%), except in the gluon--gluon fusion mechanism at relatively large Higgs boson masses, where they can reach the level of 10% (15%) at the LHC (Tevatron).Comment: 10 pages and 5 psfigure

    Characterization of single-crystal synthetic diamond for multi-watt continuous-wave Raman lasers

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    A continuous-wave diamond Raman laser is demonstrated with an output power of 5.1 W at 1217 nm. This Raman laser is intracavity pumped by a side-pumped Nd:YLF rod laser: a 43-fold brightness enhancement between the Nd:YLF and diamond Raman lasers is observed, with the M2 beam propagation factor of the diamond Raman laser measured to be <; 1.2. Although higher output powers are demonstrated in a similar configuration using KGd(WO4)2 (KGW) as the Raman laser material (6.1 W), the brightness enhancement is much lower (2.5 fold) due to the poorer beam quality of the KGW Raman laser (M2 <; 6). The Raman gain coefficient of single-crystal synthetic diamond at a pump wavelength of 1064-nm is also measured: a maximum value of 21±2 cm/GW is returned compared to 5.7±0.5 cm/GW for KGW at the same wavelength

    Use of AlInN layers in optical monitoring of growth of GaN-based structures on free-standing GaN substrates

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    When lattice matched to GaN, the AlInN ternary alloy has a refractive index ~7% lower than that of GaN. This characteristic can be exploited to perform in situ reflectometry during epitaxial growth of GaN-based multilayer structures on free-standing GaN substrates, by insertion of a suitable Al0.82In0.18N layer. The real-time information on growth rates and cumulative layer thicknesses thus obtainable is particularly valuable in the growth of optical resonant cavity structures. We illustrate this capability with reference to the growth of InGaN/GaN multiple quantum-well structures, including a doubly periodic structure with relatively thick GaN spacer layers between groups of wells. Al0.82In0.18N insertion layers can also assist in the fabrication of resonant cavity structures in postgrowth processing, for example, acting as sacrificial layers in a lift-off process exploiting etch selectivity between Al0.82In0.18N and GaN

    The effects on waiting times of expanding provider choice:evidence from a policy experiment

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    Long waiting times for inpatient treatment in the UK National Health Service have long been a source of great popular and political concern, and therefore a target for policy initiatives. One such is the London Patient Choice Project, under which patients at risk of breaching inpatient waiting time targets were offered the choice of an alternative hospital with a guaranteed shorter wait. This paper uses a difference in difference econometric methodology to infer the impact of the choice project on ophthalmology waiting times. In line with our theoretical predictions, it finds that the project led to lower average waiting times in the London region and a convergence in waiting times amongst London hospitals.
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