1,936 research outputs found
Beat Em or Join Em: Export Subsidies versus International Research Joint Ventures in Oligopolistic Markets
This paper compares adversarial with cooperative industrial and trade policies in a dynamic oligopoly game in which a home and foreign firm compete in R&D and output and, because of spillovers, each firm benefits from the other's R&D. When the government can commit to an export subsidy, such a policy raises welfare relative to cooperation, except when R&D is highly effective and spillovers are near-complete. Without commitment, however, subsidisation may yield welfare levels much lower than cooperation and lower even than free trade, though qualifications to the dangers from no commitment are noted.
Use of physical habitat structure to assess stream suitability for brown trout: a case study of three upland Scottish streams
Abstract
In 2000 the European Union introduced the Water Framework Directive, new legislation that regulates the use of surface waters within the European Community. The goal of this legislation is to protect, enhance and restore all surface waters within the Community to Good Surface Water Status. Good-Status is described as having low levels of anthropogenic distortion in its hydro-morphological and physiochemical components as well as possessing biota that would normally be associated with the type-specific aquatic ecosystem. The assessment of ecosystem status is to be defined by comparisons with intact representative reference sites, by using modelling techniques that define reference conditions, a combination of the two, or expert judgement. As undisturbed aquatic ecosystems are rare or non-existent in Europe the base-line data will have to be defined using the latter methodologies.
The aim of this project is to help define reference conditions for lotic systems in Europe based on the physical instream habitat parameters of a resident species. Brown trout (Salmo trutta), a ubiquitous and well studies species endemic to Europe, was used as the target organism to develop the assessment protocol. The project focused on the requirements this species has of aspects of its physical habitat; specifically, its usage of depth, velocity, and substrate. An extensive survey of the scientific literature was used to define the requirements trout has for the three physical parameters at four life stages. These are the spawning, nursery, juvenile and adult-resident life stages. These requirements were expressed as tolerance profiles, which defined suitable, usable and not-suitable habitat. The methodology was demonstrated by evaluating the physical habitat available at six reaches in three small streams, March, Burnhouse and Bin Burns, which drain into the Carron Valley Reservoir in central Scotland.
From the perspective of water depth, these streams seem best suited as nursery areas, are less well suited as juvenile habitat, and do not appear to be well matched for adult residents. The assessment of both velocity and substrate indicated that the portion of the study reaches available for use by resident brown trout increased with trout size. The assessment of all three physical habitat parameters at all study reaches found variable portions of the streams suitable for use by spawning trout. When the habitat variables are integrated all stream segments streams seem best suited as nursery and spawning areas. To a lesser extent juvenile trout can use these burns and very little habitat is available for use by adult resident trout.
The tolerance profiles that were created in this study are standardized assessment criteria that when compared with stream survey data can produce an appraisal of habitat availability in any fluvial freshwater system that supports populations of brown trout (Salmo trutta). The assessment method can be combined to produce an integrated habitat assessment, using both an index and by the calculation of Froude number, which is a more realistic approach than the assessment of individual habitat parameters as salmonids choose their microhabitat based on multiple factors. This approach allows an investigator to determine the amount and relative portion of useable habitat and to determine the quality of that habitat. Finally, by examining the physical habitat variable that most strongly correlates with the final integrated habitat distribution the individual habitat parameter that is most important to the distribution of physical habitat at a site can be determined. While this technique would certainly benefit from further development it does show potential to aid in physical habitat assessment of trout streams
Constitutional Law - Equal Protection Clause - Imprisonment of Indigent for Nonpayment of Fine Declared Unconstitutional - In re Antazo, 3 Cal. 3d 100, 473 P.2d 999, 89 Cal. Rptr. 255 (1970).
Thiadiazolidine 1-oxide systems for phosphine-free palladium-mediated catalysis
We herein report several highly active catalyst systems with thiadiazolidine 1-oxides as ligands for palladium in the Mizoroki–Heck reaction. Excellent yields of stilbenes derived from aryl iodides and bromides have been achieved using as little as 0.00002 mol % catalyst. The ligand/palladium system can be stored as a stock solution open to air at room temperature with no observable loss of activity for a period of several months
Estimation of minimally important differences in EQ-5D utility and VAS scores in cancer
We wish to correct a mistake in the abstract and conclusion of our published paper [1]. In the abstract and conclusion, the MID for EQ-VAS score should be reported as 7 rather than 0.07. EQ-VAS scores range from 0 to 100, while EQ-5D index-based scores are anchored by 0 (dead) and 1 (perfect health). The specific wording in the conclusion of the abstract should read “Important differences in EQ-5D utility and VAS scores were similar for all cancers and lung cancer, with the lower end of the range of estimates closer to the MID, i. e. 0.08 for UK-index scores, 0.06 for US-index scores, and 7 for VAS scores. Author details
Adaptive space-meshing strategies for the numerical solution of parabolic partial differential equations in one space dimension
The effectiveness of adaptive space-meshing in the solution of one-dimensional parabolic partial differential equations (PDEs) is assessed.
Present day PDE software typically involves discretisation in space (using Finite Differences or Finite Elements) to produce a system of ordinary differential equations (ODEs) which is then solved routinely using currently available high quality ODE integrators. Such approaches do not attempt to control the errors in the spatial discretisation and th e task of ensuring an effective spatial approxim ation and num erical grid are left entirely to the user. Numerical experiments with Burgers’ equation demonstrate the inadequacies of this approach and suggest the need foradaptive spatial m eshing as the problem evolves. The currently used adaptive m eshing techniques for parabolic problems are reviewed and two effective strategies are selected for study. Numerical experim ents dem onstrate their effectiveness in term s of reduced com putational overhead and increased accuracy. From these experiences possible future trends in adaptive meshing can be identified
Evaluation of the Impact of Transthoracic Endoscopic Sympathectomy on Patients with Palmar Hyperhydrosis
AbstractObjectives. We assessed the impact of transthoracic endoscopic sympathectomy (TES) on the quality of life of patients with palmar hyperhydrosis.Design. A retrospective questionnaire based study.Methods. Patients undergoing TES at our institution between 1997 and 2002 received a SF-36 quality of life postal questionnaire. The pre- and post-operative symptoms were assessed. Statistical analysis was by means of the Student's t test.Results. Ninety-four TES were carried out in 62 patients. Forty-one cases were female. The age range was 17–64 years. The mean follow-up period was 38.46 months. Mean hospital stay was 3 days. Compensatory hyperhydrosis was reported in 29 cases and only considered severe in four cases (9.7%). Forty-one patients replied to the questionnaire (66%). The overall quality of life (as assessed by the SF-36 form) was unanimously improved (p<0.0009) and demonstrated significant improvements in social functioning (p<0.0002), physical role limitations (p<0.0007), emotional well-being (p<0.0007) and overall energy levels (p<0.05).Conclusion. TES resulted in significant improvements inpatient's overall quality of life, social and emotional functioning. The procedure is associated with minimal morbidity and only a short inpatient stay is required. Patients should be cautioned on the possibility of compensatory hyperhydrosis which may occur in a small number of cases
The first enantiomerically pure thiadiazol-3-one 1-oxide and thiatriaza-indene 3-oxide systems chiral at the sulfur atom
The first synthesis of an enantiomerically pure C2 symmetric benzothiadiazole 2-oxide is described along with the first synthesis of an enantiomerically thiadiazol-3-one 1-oxide and a thiatriaza-indene 3-oxide system both chiral at the sulfur atom. Excellent levels of diastereoselectivity were observed in the SO installation step, that is, the reaction of the prerequisite bis-amines with thionyl chloride at ambient temperature
Use of physical habitat structure to assess stream suitability for brown trout : a case study of three upland Scottish streams
In 2000 the European Union introduced the Water Framework Directive, new legislation that regulates the use of surface waters within the European Community. The goal of this legislation is to protect, enhance and restore all surface waters within the Community to Good Surface Water Status. Good-Status is described as having low levels of anthropogenic distortion in its hydro-morphological and physiochemical components as well as possessing biota that would normally be associated with the type-specific aquatic ecosystem. The assessment of ecosystem status is to be defined by comparisons with intact representative reference sites, by using modelling techniques that define reference conditions, a combination of the two, or expert judgement. As undisturbed aquatic ecosystems are rare or non-existent in Europe the base-line data will have to be defined using the latter methodologies. The aim of this project is to help define reference conditions for lotic systems in Europe based on the physical instream habitat parameters of a resident species. Brown trout (Salmo trutta), a ubiquitous and well studies species endemic to Europe, was used as the target organism to develop the assessment protocol. The project focused on the requirements this species has of aspects of its physical habitat; specifically, its usage of depth, velocity, and substrate. An extensive survey of the scientific literature was used to define the requirements trout has for the three physical parameters at four life stages. These are the spawning, nursery, juvenile and adult-resident life stages. These requirements were expressed as tolerance profiles, which defined suitable, usable and not-suitable habitat. The methodology was demonstrated by evaluating the physical habitat available at six reaches in three small streams, March, Burnhouse and Bin Burns, which drain into the Carron Valley Reservoir in central Scotland. From the perspective of water depth, these streams seem best suited as nursery areas, are less well suited as juvenile habitat, and do not appear to be well matched for adult residents. The assessment of both velocity and substrate indicated that the portion of the study reaches available for use by resident brown trout increased with trout size. The assessment of all three physical habitat parameters at all study reaches found variable portions of the streams suitable for use by spawning trout. When the habitat variables are integrated all stream segments streams seem best suited as nursery and spawning areas. To a lesser extent juvenile trout can use these burns and very little habitat is available for use by adult resident trout. The tolerance profiles that were created in this study are standardized assessment criteria that when compared with stream survey data can produce an appraisal of habitat availability in any fluvial freshwater system that supports populations of brown trout (Salmo trutta). The assessment method can be combined to produce an integrated habitat assessment, using both an index and by the calculation of Froude number, which is a more realistic approach than the assessment of individual habitat parameters as salmonids choose their microhabitat based on multiple factors. This approach allows an investigator to determine the amount and relative portion of useable habitat and to determine the quality of that habitat. Finally, by examining the physical habitat variable that most strongly correlates with the final integrated habitat distribution the individual habitat parameter that is most important to the distribution of physical habitat at a site can be determined. While this technique would certainly benefit from further development it does show potential to aid in physical habitat assessment of trout streams.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
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