474 research outputs found
Understanding the Costs and Benefits of Deepwater Oil Drilling Regulation
The purpose of this paper is to provide a conceptual framework for understanding how analysis of costs and benefits might be incorporated into an assessment of regulatory policies affecting deepwater drilling. We begin by providing a framework for analyzing the life-cycle impacts of oil drilling and its alternatives, including onshore drilling and importing oil from abroad. We then provide background estimates of the different sources of oil supplied in the United States, look at how other oil supply sources might respond to regulations on deepwater drilling, and consider the economic costs of these regulations. After providing a comprehensive description of the potential costs and benefits from various types of drillingâincluding, when possible, estimates of the magnitude of these benefits and costsâwe discuss the extent to which these costs and benefits may already be taken into account (or reinforced) through the legal, regulatory, and tax systems and through market mechanisms. We conclude by presenting a framework and simple example of how a costâbenefit analysis might be used to inform regulation of deepwater drilling, and sum up the policy implications of our work.catastrophic oil spill, cost-benefit analysis, government regulation, liability
Tekstbegrip en klantbelang bij financiële producten
De laatste jaren is tekstbegrip van consumenten in de belangstelling gekomen in de wereld van financiële dienstverlening. Onduidelijkheid van productvoorwaarden, folders en brieven zou bijdragen aan wantrouwen in deze sector. Omgekeerd wordt vaak gedacht dat het verbeteren van duidelijkheid van teksten in het belang van de klant is en resulteert in het herstel van vertrouwen. Onderzoek laat echter zien dat het allemaal niet zo eenvoudig is. Tekstbegrip is een moeilijk waar te nemen fenomeen dat opgebouwd lijkt te zijn uit een complexe keten van contextafhankelijke variabelen. Bovendien is het verband tussen tekstbegrip en klantbelang niet evident. In deze bijdrage proberen we de materie te ontrafelen en te ordenen. Een aantal vragen staat daarbij centraal: Wat maakt dat mensen productvoorwaarden, algemene voorwaarden en soortgelijke juridisch relevante teksten wel of niet lezen? Wat is duidelijkheid van tekst en hoe meet je die bij juridische teksten? Is er verband tussen de mate van duidelijkheid van de tekst en consumentengedrag? In deze bijdrage geven we een overzicht van de wetenschappelijke literatuur op dit gebied en evalueren we de uitkomsten daarvan
Henry Cadellâs Experimental Researches in Mountain Building : their lessons for interpreting thrust systems and fold-thrust structures
Funding The Fold-Thrust Research Group has been funded by InterOil, Santos, OilSearch and NAGRA. The original compilation of Cadellâs researches was part of an outreach programme funded by BP. Acknowledgements RWHB is indebted to the late John Mendum for arranging access to Cadellâs notebooks and his field maps that were lodged in the then offices of the British Geological Survey in Murchison House, Edinburgh. This formed part of a collaboration with BGS and the development of the âAssyntâs Geologyâ website in the early 2000s. Many of the images from Cadellâs notebooks, including his experimental results, were part of this site. Regrettably it has not been maintained and is no longer accessible. Rectifying this loss of resource forms the motivation for this contribution. We thank Juergen Adam and an anonymous referee for construct reviews, together with James Hammerstein for shepherding the manuscript through the editing process, although of course the views expressed in this paper remain the responsibility of the authors alone.Peer reviewedPostprin
Een onverantwoorde inzet op eigen verantwoordelijkheid. âEigen Krachtâ tussen autonomie en controle.
Feiten van algemene bekendheid en ervaringsregels - virtuele werkelijkheid?
âFeiten van algemene bekendheidâ en zogenaamde âervaringsregelsâ kunnen belangrijke schakels zijn in rechterlijke beslissingen. Maar ze hoeven geen bewijs en rechters kunnen ze tamelijk vrijelijk gebruiken. De vraag is dus welke feiten en fenomenen wel en niet feiten van algemene bekendheid en ervaringsregels opleveren. Naar aangenomen mag worden, hebben rechterlijke oordelen waarin feiten van algemene bekendheid gebruikt worden, werkelijkheidspretentie, want zij lijken te refereren aan kwesties die elk weldenkend mens zonder uitvoerig nadenken zelf ook kan weten. Maar is dat ook echt zo, of moeten we concluderen dat sprake is van een virtuele werkelijkheid? In deze bijdrage analyseren wij de civielrechtelijke rechtspraak waarin feiten van algemene bekendheid en ervaringsregels worden gehanteerd, welke onderverdelingen daarbij mogelijk zijn en tot welke consequenties het gebruik
daarvan leidt. Vervolgens leggen wij een aantal feiten van algemene bekendheid, zoals deze in de rechtspraak gehanteerd zijn, voor aan een groep personen om te toetsen hoe bekend feiten van algemene bekendheid werkelijk zijn. De conclusie is dat inderdaad soms van een virtuele werkelijkheid sprake is en dat rechters daarom de contextualiteit van het gebruik van de begripp
Spatial Degrees of Freedom in Everett Quantum Mechanics
Stapp claims that, when spatial degrees of freedom are taken into account,
Everett quantum mechanics is ambiguous due to a "core basis problem." To
examine an aspect of this claim I generalize the ideal measurement model to
include translational degrees of freedom for both the measured system and the
measuring apparatus. Analysis of this generalized model using the Everett
interpretation in the Heisenberg picture shows that it makes unambiguous
predictions for the possible results of measurements and their respective
probabilities. The presence of translational degrees of freedom for the
measuring apparatus affects the probabilities of measurement outcomes in the
same way that a mixed state for the measured system would. Examination of a
measurement scenario involving several observers illustrates the consistency of
the model with perceived spatial localization of the measuring apparatus.Comment: 34 pp., no figs. Introduction, discussion revised. Material
tangential to main point remove
Scaling in Numerical Simulations of Domain Walls
We study the evolution of domain wall networks appearing after phase
transitions in the early Universe. They exhibit interesting dynamical scaling
behaviour which is not yet well understood, and are also simple models for the
more phenomenologically acceptable string networks. We have run numerical
simulations in two- and three-dimensional lattices of sizes up to 4096^3. The
theoretically predicted scaling solution for the wall area density A ~ 1/t is
supported by the simulation results, while no evidence of a logarithmic
correction reported in previous studies could be found. The energy loss
mechanism appears to be direct radiation, rather than the formation and
collapse of closed loops or spheres. We discuss the implications for the
evolution of string networks.Comment: 7pp RevTeX, 9 eps files (including six 220kB ones
Crystal Structures of Native and Inactivated cis-3-Chloroacrylic Acid Dehalogenase. Structural Basis for Substrate Specificity and Inactivation by (R)-Oxirane-2-Carboxylate
The bacterial degradation pathways for the nematocide 1,3-dichloropropene rely on hydrolytic dehalogenation reactions catalyzed by cis- and trans-3-chloroacrylic acid dehalogenases (cis-CaaD and CaaD, respectively). X-ray crystal structures of native cis-CaaD and cis-CaaD inactivated by (R)-oxirane-2-carboxylate were elucidated. They locate four known catalytic residues (Pro-1, Arg-70, Arg-73, and Glu-114) and two previously unknown, potential catalytic residues (His-28 and Tyr-103'). The Y103F and H28A mutants of these latter two residues displayed reductions in cis-CaaD activity confirming their importance in catalysis. The structure of the inactivated enzyme shows covalent modification of the Pro-1 nitrogen atom by (R)-2-hydroxypropanoate at the C3 position. The interactions in the complex implicate Arg-70 or a water molecule bound to Arg-70 as the proton donor for the epoxide ring-opening reaction and Arg-73 and His-28 as primary binding contacts for the carboxylate group. This proposed binding mode places the (R)-enantiomer, but not the (S)-enantiomer, in position to covalently modify Pro-1. The absence of His-28 (or an equivalent) in CaaD could account for the fact that CaaD is not inactivated by either enantiomer. The cis-CaaD structures support a mechanism in which Glu-114 and Tyr-103' activate a water molecule for addition to C3 of the substrate and His-28, Arg-70, and Arg-73 interact with the C1 carboxylate group to assist in substrate binding and polarization. Pro-1 provides a proton at C2. The involvement of His-28 and Tyr-103' distinguishes the cis-CaaD mechanism from the otherwise parallel CaaD mechanism. The two mechanisms probably evolved independently as the result of an early gene duplication of a common ancestor
Structural basis for the catalytic mechanism of ethylenediamine-N,NâČ-disuccinic acid lyase, a carbon-nitrogen bond-forming enzyme with broad substrate scope
The natural aminocarboxylic acid product ethylenediamine-N,NâČ-disuccinic acid [(S,S)-EDDS] is able to form a stable complex with metal ions, making it an attractive biodegradable alternative for the synthetic metal chelator ethylenediamine tetraacetic acid (EDTA), which is currently used at large scale in numerous applications. Previous studies have demonstrated that biodegradation of (S,S)-EDDS may be initiated by an EDDS lyase, converting (S,S)-EDDS via the intermediate N-(2-aminoethyl)aspartic acid (AEAA) into ethylenediamine and two molecules of fumarate. However, current knowledge of this enzyme is limited due to the absence of structural data. Here, we describe the identification and characterization of an EDDS lyase from Chelativorans sp. BNC1, which has a broad substrate scope, accepting various mono- and diamines for addition to fumarate. We report crystal structures of the enzyme in an unliganded state and in complex with formate, succinate, fumarate, AEAA and (S,S)-EDDS. The structures reveal a tertiary and quaternary fold that is characteristic of the aspartase/fumarase superfamily and support a mechanism that involves general base-catalyzed, sequential two-step deamination of (S,S)-EDDS. This work broadens our understanding of mechanistic diversity within the aspartase/fumarase superfamily and will aid in the optimization of EDDS lyase for asymmetric synthesis of valuable (metal-chelating) aminocarboxylic acids
Assessing the effectiveness of business support services in England: evidence from a theory based evaluation
In England, publicly supported advisory services for small firms are organised primarily through the Business Link (BL) network. Based on the programme theory underlying this business support services we develop four propositions and test these empirically using data from a new survey of over 3,000 English small firms. Our empirical results provide a broad validation of the programme theory underlying BL assistance for small firms in England during 2003, and more limited support for its effectiveness. More specifically, we find strong support for the value of BL operators maintaining a high profile as a way of boosting take-up. We also find some support for the approach to market segmentation adopted by BL allowing more intensive assistance to be targeted on younger firms and those with limited liability status. In terms of the outcomes of BL support, and allowing for issues of sample selection, we find no significant effects on growth from âotherâ assistance but do find positive and significant employment growth effects from intensive assistance. This provides partial support for the programme theory assertion that BL support will lead to improvements in business growth performance and stronger support for the proposition that there would be differential outcomes from intensive and other assistance. The positive employment growth outcomes identified here from intensive assistance, even allowing for sample selection, suggest something of an improvement in the effectiveness of the BL network since the late 1990s
- âŠ