This paper develops an analytical framework for estimating the second-best optimal gasoline tax, accounting for passenger vehicle externalities and the efficient balance between excise taxes and ...labor taxes in financing the government's budget. We estimate the optimal tax for the United States at $1.01/gallon, which is 2.5 times the current rate; for the United Kingdom, the optimal tax of $1.34/gallon is about half its current rate. However, welfare gains from replacing fuel taxes with per mile taxes are large for both countries. If taxes were on mileage rather than fuel, UK motorists would be undercharged rather than overcharged at current revenues. PUBLICATION ABSTRACT
Automobile Externalities and Policies Parry, Ian W. H.; Walls, Margaret; Harrington, Winston
Journal of economic literature,
06/2007, Letnik:
45, Številka:
2
Journal Article
Recenzirano
This paper discusses the nature, and magnitude, of externalities associated with automobile use, including local and global pollution, oil dependence, traffic congestion and traffic accidents. It ...then discusses current federal policies affecting these externalities, including fuel taxes, fuel economy and emissions standards, and alternative fuel policies, summarizing, insofar as possible, the welfare effects of those policies. Finally, we discuss emerging pricing policies, including congestion tolls, and insurance reform, and summarize the appropriate combination of policies to address automobile externalities.
This paper derives empirically tractable formulas for the welfare effects of fare adjustments in passenger peak and off-peak rail and bus transit, and for optimal pricing of those services. The ...formulas account for congestion, pollution, accident externalities, scale economies, and agency adjustment of transit service offerings. We apply them using parameter values for Washington (DC), Los Angeles, and London. The results support the efficiency of the large current fare subsidies; even starting with fares at 50 percent of operating costs, incremental fare reductions are welfare improving in almost all cases. These findings are robust to alternative assumptions and parameters.
Greater understanding of the risk factors and mechanisms of incident dementia in stroke survivors is needed for prevention and management. There is limited information on the long-term consequences ...and forms of incident dementia in older stroke survivors. We recruited 355 patients aged >75 years from hospital-based stroke registers into a longitudinal study 3 months after stroke. At baseline none of the patients had dementia. Patients were genotyped for apolipoprotein E and assessed annually for cognition and development of incident dementia over up to 8 years of follow-up. The effect of baseline vascular risk factors upon incidence of dementia and mortality were estimated by Cox proportional regression analyses adjusted for age and gender. Standard neuropathological examination was performed to diagnose the first 50 cases that came to autopsy. We found that the median survival from the date of the index stroke was 6.72 years (95% confidence intervals: 6.38-7.05). During the follow-up of a mean time of 3.79 years, 23.9% of subjects were known to have developed dementia and 76.1% remained alive without dementia or died without dementia. The incidence of delayed dementia was calculated to be 6.32 cases per 100 person years whereas that for death or dementia was 8.62. Univariate and multivariate regression analyses showed that the most robust predictors of dementia included low (1.5 standard deviations below age-matched control group) baseline Cambridge Cognitive Examination executive function and memory scores, Geriatric Depression Scale score and three or more cardiovascular risk factors. Autopsy findings suggested that remarkably 75% of the demented stroke survivors met the current criteria for vascular dementia. Demented subjects tended to exhibit marginally greater neurofibrillary pathology including tauopathy and Lewy bodies and microinfarcts than non-demented survivors. Despite initial improvements in cognition following stroke in older stroke survivors, risk of progression to delayed dementia after stroke is substantial, but is related to the presence of vascular risk factors. Careful monitoring and treatment of modifiable vascular risk factors may be of benefit in preventing post-stroke dementia in the general population.
Instrument Choice in Environmental Policy Goulder, Lawrence H.; Parry, Ian W. H.
Review of environmental economics and policy,
07/2008, Letnik:
2, Številka:
2
Journal Article
Recenzirano
The choice of pollution control instrument is a crucial environmental policy decision. We examine the extent to which various environmental policy instruments meet major evaluation criteria, ...including cost-effectiveness, distributional equity, the ability to address uncertainties, and political feasibility. Instruments considered include emissions taxes, tradable emissions allowances, subsidies for emissions reductions, performance standards, mandates for the adoption of specific technologies, and subsidies for research toward new, “clean” technologies. We consider policies that address pollution externalities and policies that deal with market failures associated with efforts to invent or deploy new technologies. Several themes emerge. First, no single instrument is clearly superior along all the dimensions relevant to policy choice; even the ranking along a single dimension often depends on the circumstances involved. Second, significant trade-offs arise in the choice of instrument: for example, assuring a reasonable degree of distributional equity will often require a sacrifice of cost-effectiveness. Third, it is sometimes desirable to design hybrid instruments that combine features of various “pure” instruments. Fourth, for many pollution problems, more than one market failure may be involved, which may justify (on efficiency grounds, at least) employing more than one instrument. Finally, potential interactions among environmental policy instruments and among regulatory jurisdictions need to be carefully considered.
Designing Climate Mitigation Policy Aldy, Joseph E.; Krupnick, Alan J.; Newell, Richard G. ...
Journal of economic literature,
12/2010, Letnik:
48, Številka:
4
Journal Article
Recenzirano
Odprti dostop
This paper provides (for the nonspecialist) a highly streamlined discussion of the main issues, and controversies, in the design of climate mitigation policy. The first part of the paper discusses ...how much action to reduce greenhouse gas emissions at the global level is efficient under both the cost-effectiveness and welfare-maximizing paradigms. We then discuss various issues in the implementation of domestic emissions control policy, instrument choice, and incentives for technological innovation. Finally, we discuss alternative policy architectures at the international level.
Please cite this paper as: Underwood M, Arbyn M, Parry‐Smith W, De Bellis‐Ayres S, Todd R, Redman CWE, Moss EL. Accuracy of colposcopy‐directed punch biopsies: a systematic review and meta‐analysis. ...BJOG 2012;119:1293–1301.
Background The colposcopy‐directed punch biopsy is widely used in the management of women with abnormal cervical cytology; however, its accuracy compared with definitive histology from an excision biopsy is not well established.
Objectives To assess the accuracy of the colposcopy‐directed punch biopsy to diagnose high‐grade cervical intraepithelial neoplasia (CIN) by performing a systematic review and meta‐analysis.
Search strategy A systematic search of MEDLINE, EMBASE and the Cochrane Library was performed.
Selection criteria Articles that compared the colposcopically directed cervical punch biopsy with definitive histology from an excisional cervical biopsy or hysterectomy.
Data collection and analysis Random effects and hierarchical summary receiver operating characteristic regression models were used to compute the pooled sensitivity and specificity applying different test cut‐offs for outcomes of high‐grade CIN.
Main results Thirty‐two papers comprising 7873 paired punch/definitive histology results were identified. The pooled sensitivity for a punch biopsy defined as test cut‐off CIN1+ to diagnose CIN2+ disease was 91.3% (95% CI 85.3–94.9%) and the specificity was 24.6% (95% CI 16.0–35.9%). In most of the studies, the majority of enrolled women had positive punch biopsies. Pooling of the four studies where the excision biopsy was performed immediately after the punch biopsy, and where the rate of positive punch biopsies was considerably lower, yielded a sensitivity of 81.4% and specificity of 63.3%.
Author’s conclusion The observed high sensitivity of the punch biopsy derived from all studies is probably the result of verification bias.
IntroductionThe ageing population poses an increasing burden to public health systems, particularly as a result of falls. Falls have been associated with poor gait and balance, as measured by ...commonly used clinical tests for poor gait and balance. Falls in older adults have the potential to lead to long-term issues with mobility and a fear of falling (FoF). FoF is measured by a variety of instruments; the Falls Efficacy Scale International (FES-I) version is widely used within clinical and research arenas. The ability of the FoF, as measured by the FES-I to predict gait and balance abnormalities (GABAb) has not previously been measured; this study aims to be the first to investigate this prospective relationship.Methods and analysesTo investigate the ability of the FES-I to predict GABAb a mixed-methods approach will be used, including quantitative, qualitative and health economics approaches. Initially the ability of the FES-I to identify poor gait and balance will be investigated, along with whether the measure is able to assess change in gait and balance in response to exercise training. The ability of an online FES-I tool to assess poor gait and balance in an alternative pre-existing online strength and balance programme will also be investigated. Interviews will be carried out to investigate participant experiences and motivations of those that are offered Age UK Strength and Balance Training, along with the views of healthcare professionals and Age UK staff involved within the process.Ethics and disseminationNHS REC Approval has been granted (IRAS ID 314705). Study participation is voluntary; participants will be provided with all necessary information within the participant information sheet, with written consent being sought. Study findings will be disseminated through manuscripts in peer-reviewed journals, at scientific conferences and in a short report to participants and the funding body.
Circadian rhythms organize many aspects of cell biology and physiology to a daily temporal program that depends on clock gene expression cycles in most mammalian cell types. However, circadian ...rhythms are also observed in isolated mammalian red blood cells (RBCs), which lack nuclei, suggesting the existence of post-translational cellular clock mechanisms in these cells. Here we show using electrophysiological and pharmacological approaches that human RBCs display circadian regulation of membrane conductance and cytoplasmic conductivity that depends on the cycling of cytoplasmic K
levels. Using pharmacological intervention and ion replacement, we show that inhibition of K
transport abolishes RBC electrophysiological rhythms. Our results suggest that in the absence of conventional transcription cycles, RBCs maintain a circadian rhythm in membrane electrophysiology through dynamic regulation of K
transport.
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