986 resultados para Routes d’invasion
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This thesis presents a techno-economic investigation of the generation of electricity from marine macroalgae (seaweed) in the UK (Part 1), and the production of anhydrous ammonia from synthesis gas (syngas) generated from biomass gasification (Part 2). In Part 1, the study covers the costs from macroalgae production to the generation of electricity via a CHP system. Seven scenarios, which varied the scale and production technique, were investigated to determine the most suitable scale of operation for the UK. Anaerobic digestion was established as the most suitable technology for macroalgae conversion to CHP, based on a number of criteria. All performance and cost data have been taken from published literature. None of the scenarios assessed would be economically viable under present conditions, although the use of large-scale electricity generation has more potential than small-scale localised production. Part 2 covers the costs from the delivery of the wood chip feedstock to the production of ammonia. Four cases, which varied the gasification process used and the scale of production, were investigated to determine the most suitable scale of operation for the UK. Two gasification processes were considered, these were O2-enriched air entrained flow gasification and Fast Internal Circulating Fluidised Bed. All performance and cost data have been taken from published literature, unless otherwise stated. Large-scale (1,200 tpd) ammonia production using O2-enriched air entrained flow gasification was determined as the most suitable system, producing the lowest ammonia-selling price, which was competitive to fossil fuels. Large-scale (1,200 tpd) combined natural gas/biomass syngas ammonia production also generated ammonia at a price competitive to fossil fuels.
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From a Service-Dominant Logic (S-DL) perspective, employees constitute operant resources that firms can draw to enhance the outcomes of innovation efforts. While research acknowledges that frontline employees (FLEs) constitute, through service encounters, a key interface for the transfer of valuable external knowledge into the firm, the range of potential benefits derived from FLE-driven innovation deserves more investigation. Using a sample of knowledge intensive business services firms (KIBS), this study examines how the collaboration with FLEs along the new service development (NSD) process, namely FLE co-creation, impacts on service innovation performance following two routes of different effects. Partial least squares structural equation modeling (PLS-SEM) results indicate that FLE co-creation benefits the NS success among FLEs and firm’s customers, the constituents of the resources route. FLE co-creation also has a positive effect on the NSD speed, which in turn enhances the NS quality. NSD speed and NS quality integrate the operational route, which proves to be the most effective path to impact the NS market performance. Accordingly, KIBS managers must value their FLEs as essential partners to achieve successful innovation from an internal and external perspective, and develop the appropriate mechanisms to guarantee their effective involvement along the NSD process.
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This article discusses a solution method for Hamilton Problem, which either finds the task's solution, or indicates that the task is unsolvable. Offered method has significantly smaller requirements for computing resources than known algorithms.
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Waste biomass is generated during the conservation management of semi-natural habitats, and represents an unused resource and potential bioenergy feedstock that does not compete with food production. Thermogravimetric analysis was used to characterise a representative range of biomass generated during conservation management in Wales. Of the biomass types assessed, those dominated by rush (Juncus effuses) and bracken (Pteridium aquilinum) exhibited the highest and lowest volatile compositions respectively and were selected for bench scale conversion via fast pyrolysis. Each biomass type was ensiled and a sub-sample of silage was washed and pressed. Demineralization of conservation biomass through washing and pressing was associated with higher oil yields following fast pyrolysis. The oil yields were within the published range established for the dedicated energy crops miscanthus and willow. In order to examine the potential a multiple output energy system was developed with gross power production estimates following valorisation of the press fluid, char and oil. If used in multi fuel industrial burners the char and oil alone would displace 3.9 × 105 tonnes per year of No. 2 light oil using Welsh biomass from conservation management. Bioenergy and product development using these feedstocks could simultaneously support biodiversity management and displace fossil fuels, thereby reducing GHG emissions. Gross power generation predictions show good potential.
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General note: Title and date provided by Bettye Lane.
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Muscarine was identified as an active principle of the poisonous mushroom Amanita muscaria over 170 years ago and has been identified as an agonist of acetylcholine. The synthesis of all stereoisomers of muscarine have been accomplished at this stage by chemical methods and the biological activity of these compounds tested. A number of synthetic routes to enantiomerically pure muscarine and its analogues have been published. In this work, we are focussed on the use of a novel biotransformation strategy to access these compounds. Asymmetric synthesis involves targeting a synthetic pathway leading to one enantiomer of a compound and biocatalysis is one strategy used in asymmetric synthesis. Chapter 1 consists of a review of the relevant literature pertaining to the synthesis and stereoselective transformations of 3-hydroxytetrahydrofuranss. A review of synthetic routes to these compounds is presented, with a particular focus on routes to the natural product muscarine and its analogues. Chapter 2 discusses the preparative routes to the 3-hydroxytetrahydrofurans via 3(2H)- furanones. Steps amongst which include Rh(II) mediate cyclisation and kinetic resolution via baker’s yeast mediated carbonyl reduction, resulting in enantioenriched 3- hydroxytetrahydrofuran derivatives. Finally, application of this methodology to the preparation of all four enantiomers of an analogue of desmethylmuscarine and the synthesis of epimuscarine is described. Chapter 3 consists of a detailed experimental section outlining the synthetic procedures employed.
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Objectives This paper describes the methods used in the International Cancer Benchmarking Partnership Module 4 Survey (ICBPM4) which examines time intervals and routes to cancer diagnosis in 10 jurisdictions. We present the study design with defining and measuring time intervals, identifying patients with cancer, questionnaire development, data management and analyses.
Design and setting Recruitment of participants to the ICBPM4 survey is based on cancer registries in each jurisdiction. Questionnaires draw on previous instruments and have been through a process of cognitive testing and piloting in three jurisdictions followed by standardised translation and adaptation. Data analysis focuses on comparing differences in time intervals and routes to diagnosis in the jurisdictions.
Participants Our target is 200 patients with symptomatic breast, lung, colorectal and ovarian cancer in each jurisdiction. Patients are approached directly or via their primary care physician (PCP). Patients’ PCPs and cancer treatment specialists (CTSs) are surveyed, and ‘data rules’ are applied to combine and reconcile conflicting information. Where CTS information is unavailable, audit information is sought from treatment records and databases.
Main outcomes Reliability testing of the patient questionnaire showed that agreement was complete (κ=1) in four items and substantial (κ=0.8, 95% CI 0.333 to 1) in one item. The identification of eligible patients is sufficient to meet the targets for breast, lung and colorectal cancer. Initial patient and PCP survey response rates from the UK and Sweden are comparable with similar published surveys. Data collection was completed in early 2016 for all cancer types.
Conclusion An international questionnaire-based survey of patients with cancer, PCPs and CTSs has been developed and launched in 10 jurisdictions. ICBPM4 will help to further understand international differences in cancer survival by comparing time intervals and routes to cancer diagnosis.
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[EN] The presence of the green and Kemp's ridley turtles is rare at Atlantic and Mediterranean Spanish waters, but the records have increased during the last decades. We reported a new set of records and reviewed all the historical observations of these species. The analysis of a mitochondrial DNA fragment of the newest records provided insights about the origin of the individuals. The Kemp's ridley turtles arrived from the western Atlantic nesting beaches, although the discovering of a new haplotype suggested the existence of an unknown or low sampled nesting area of origin.
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This study measured fuel consumption in transporting grain from Iowa origins to Japan and Amsterdam by alternative routes and modes of transport and applied these data to construct equations for fuel consumption from Iowa origins to alternative final destinations. Some of the results are as follows: (1) The metered tractor-trailer truck averaged 186.6 gross ton-miles per gallon and 90.5 net ton-miles per gallon when loaded 50% of total miles. (2) The 1983 fuel consumption of seven trucks taken from company records was 82.4 net ton-miles per gallon at 67.5% loaded miles and 68.6 net ton-miles per gallon at 50% loaded miles. (3) Unit grain trains from Iowa to West Coast ports averaged 437.0 net ton-miles per gallon whereas unit grain trains from Iowa to New Orleans averaged 640.1 net ton-miles per gallon--a 46% advantage for the New Orleans trips. (4) Average barge fuel consumption on the Mississippi River from Iowa to New Orleans export grain elevators was 544.5 net ton-miles per gallon, with a 35% backhaul rate. (5) Ocean vessel net ton-miles per gallon varies widely by size of ship and backhaul percentage. With no backhaul, the average net ton-miles per gallon were as follows: for 30,000 dwt ship, 574.8 net ton-miles per gallon; for 50,000 dwt ship, 701.9; for 70,000 dwt ship, 835.1; and for 100,000 dwt ship, 1,043.4. (6) The most fuel efficient route and modal combination to transport grain from Iowa to Japan depends on the size of ocean vessel, the percentage of backhaul, and the origin of the grain. Alternative routes and modal combinations in shipping grain to Japan are ranked in descending order of fuel efficiencies.
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Silicon carbide (SiC) is a promising material for electronics due to its hardness, and ability to carry high currents and high operating temperature. SiC films are currently deposited using chemical vapor deposition (CVD) at high temperatures 1500–1600 °C. However, there is a need to deposit SiC-based films on the surface of high aspect ratio features at low temperatures. One of the most precise thin film deposition techniques on high-aspect-ratio surfaces that operates at low temperatures is atomic layer deposition (ALD). However, there are currently no known methods for ALD of SiC. Herein, the authors present a first-principles thermodynamic analysis so as to screen different precursor combinations for SiC thin films. The authors do this by calculating the Gibbs energy ΔGΔG of the reaction using density functional theory and including the effects of pressure and temperature. This theoretical model was validated for existing chemical reactions in CVD of SiC at 1000 °C. The precursors disilane (Si2H6), silane (SiH4), or monochlorosilane (SiH3Cl) with ethyne (C2H2), carbontetrachloride (CCl4), or trichloromethane (CHCl3) were predicted to be the most promising for ALD of SiC at 400 °C.
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From 1974 to 1986 the Iberian Peninsula was the arena of major political changes. The process then undertaken was characterized by the transition from two Iberian authoritarian regimes to two democracies, which enabled both countries to join the European Economic Community (EEC) on 1 January 1986. However, the political vicissitudes until full membership of what became the European Union (EU) was achieved were very different and were decisively, although not exclusively, influenced by the fact Portugal was a republic and Spain a monarchy. In Portugal the 1974 revolution took place with consequent shift of the head of state while in Spain the engine of change was precisely the head of state: King Juan Carlos I. It is also true that despite the dangers to democracy (terrorism in Spain and some radicalism in Portugal) both societies supported the political parties committed to the democratic process in elections, which helped avoid tensions that could have defeated the process. Likewise, it is possible to argue that in Spain a plan to achieve democracy within the rule of law (an archetypal transition) was designed by the head of state, while in Portugal there was no pre-established plan – the programme of the Armed Forces Movement (Movimento das Forças Armadas [MFA]) was a weak and precarious compromise between different visions of the road to follow, enabling an intense political struggle that almost led to civil war and a dangerous state of crisis.
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BACKGROUND The uncontrolled presence of African swine fever (ASF) in Russian Federation (RF) poses a serious risk to the whole European Union (EU) pig industry. Although trade of pigs and their products is banned since the official notification in June 2007, the potential introduction of ASF virus (ASFV) may occur by other routes, which are very frequent in ASF, and more difficult to control, such as contaminated waste or infected vehicles. This study was intended to estimate the risk of ASFV introduction into the EU through three types of transport routes: returning trucks, waste from international ships and waste from international planes, which will be referred here as transport-associated routes (TAR). Since no detailed and official information was available for these routes, a semi-quantitative model based on the weighted combination of risk factors was developed to estimate the risk of ASFV introduction by TAR. Relative weights for combination of different risk factors as well as validation of the model results were obtained by an expert opinion elicitation. RESULTS Model results indicate that the relative risk for ASFV introduction through TAR in most of the EU countries (16) is low, although some countries, specifically Poland and Lithuania, concentrate high levels of risk, the returning trucks route being the analyzed TAR that currently poses the highest risk for ASFV introduction into the EU. The spatial distribution of the risk of ASFV introduction varies importantly between the analyzed introduction routes. Results also highlight the need to increase the awareness and precautions for ASF prevention, particularly ensuring truck disinfection, to minimize the potential risk of entrance into the EU. CONCLUSIONS This study presents the first assessment of ASF introduction into the EU through TAR. The innovative model developed here could be used in data scarce situations for estimating the relative risk associated to each EU country. This simple methodology provides a rapid and easy to interpret results on risk that may be used for a target and cost-effective allocation of resources to prevent disease introduction.
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Scuba diving allows for underwater visitation of cultural and natural resources. Underwater routes can be used as a tool for guided and supervised underwater visits. Two scuba diving routes were implemented in the Algarve (South of Portugal), the "B24" and "Poco" diving sites. The perceptions of scuba divers regarding several aspects of the routes and the existing support infrastructures were studied following a survey carried out through face-to-face interviews from 2008 to 2012. Divers profile and their perceptions were analysed using 246 valid questionnaires. Divers were mainly Portuguese, over 30 years old and with more than 12 years of formal education. Some of the support infrastructures did not achieve a "good" or "acceptable" grade. This should be carefully considered by diving operators and managers, because perceptions tend to circulate throughout the diving tourists. All features of interpretative slates were graded as highly satisfactory. Overall, diver satisfaction increased slightly after route implementation, with an average ranking of "good". These findings support the implementation of underwater routes as a way to promote diving activity, and to increase divers' environmental education and awareness. (C) 2013 Elsevier Ltd. All rights reserved.