253 research outputs found

    Economic Growth and Threatened and Endangered Species Listings: A VAR Analysis

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    We conduct several analyses to examine the link between threatened and endangered species listings and macroeconomic activity. Preliminary tests using ordinary least squares are run on both time series data on the national level and cross sectional data at the state level. The analysis is then extended using vector autoregressive (VAR) techniques. VAR results, impulse response functions and variance decompositions are reported to shed more light on the causal relationships between threatened and endangered species, GDP and population. Our results indicate that there is little or no empirical evidence that GDP growth rates lead to changes in the number of threatened and endangered species listings.

    Economic Growth and Threatened and Endangered Species Listings: A VAR Analysis

    Get PDF
    We conduct several analyses to examine the link between threatened and endangered species listings and macroeconomic activity. Preliminary tests using ordinary least squares are run on both time series data on the national level and cross sectional data at the state level. The analysis is then extended using vector autoregressive (VAR) techniques. VAR results, impulse response functions and variance decompositions are reported to shed more light on the causal relationships between threatened and endangered species, GDP and population. Our results indicate that there is little or no empirical evidence that GDP growth rates lead to changes in the number of threatened and endangered species listings. Key Words: Economic growth, endangered and threatened species, vector autoregression

    Stochastic Dominance, Entropy and Biodiversity Management

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    In this paper we develop a model of population dynamics using the Shannon entropy index, a measure of diversity that allows for global and specific population shocks. We model the effects of increasing the number of parcels on biodiversity, varying the number of spatially diverse parcels to capture risk diversification. We discuss the concepts of stochastic dominance as a means of project selection, in order to model biodiversity returns and risks. Using a Monte Carlo simulation we find that stochastic dominance may be a useful theoretical construct for project selections but it is unable to rank every case.

    Stochastic Dominance, Entropy and Biodiversity Management

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    In this paper we develop a model of population dynamics using the Shannon entropy index, a measure of diversity that allows for global and specific population shocks. We model the effects of increasing the number of parcels on biodiversity, varying the number of spatially diverse parcels to capture risk diversification. We discuss the concepts of stochastic dominance as a means of project selection, in order to model biodiversity returns and risks. Using a Monte Carlo simulation we find that stochastic dominance may be a useful theoretical construct for project selections but it is unable to rank every case. Key Words: Stochastic Dominance, Entropy, Biodiversity Management

    Waiting to Execute: An Optimal Stopping Model of Capital Punishment Stays

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    The focus of this paper is on a specific component of the capital punishment debate: delays in capital punishment. Although the legal justifications for delays in capital punishment cases, such as the right of the writ of habeas corpus, are well known, the analysis of the economic costs and benefits of delaying executions is limited. Fluctuations in the political consensus regarding capital punishment and resulting changes in the imposition of the death penalty in practice suggest that such costs and benefits are important to policymakers. The employment of option value theory is useful when considering the implementation of the death penalty because it involves an action that has uncertain net benefits and that is irreversible.Punishment

    Identification of potential CepR regulated genes using a cep box motif-based search of the Burkholderia cenocepacia genome

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    BACKGROUND: The Burkholderia cenocepacia CepIR quorum sensing system has been shown to positively and negatively regulate genes involved in siderophore production, protease expression, motility, biofilm formation and virulence. In this study, two approaches were used to identify genes regulated by the CepIR quorum sensing system. Transposon mutagenesis was used to create lacZ promoter fusions in a cepI mutant that were screened for differential expression in the presence of N-acylhomoserine lactones. A bioinformatics approach was used to screen the B. cenocepacia J2315 genome for CepR binding site motifs. RESULTS: Four positively regulated and two negatively regulated genes were identified by transposon mutagenesis including genes potentially involved in iron transport and virulence. The promoter regions of selected CepR regulated genes and site directed mutagenesis of the cepI promoter were used to predict a consensus cep box sequence for CepR binding. The first-generation consensus sequence for the cep box was used to identify putative cep boxes in the genome sequence. Eight potential CepR regulated genes were chosen and the expression of their promoters analyzed. Six of the eight were shown to be regulated by CepR. A second generation motif was created from the promoters of these six genes in combination with the promoters of cepI, zmpA, and two of the CepR regulated genes identified by transposon mutagenesis. A search of the B. cenocepacia J2315 genome with the new motif identified 55 cep boxes in 65 promoter regions that may be regulated by CepR. CONCLUSION: Using transposon mutagenesis and bioinformatics expression of twelve new genes have been determined to be regulated by the CepIR quorum sensing system. A cep box consensus sequence has been developed based on the predicted cep boxes of ten CepR regulated genes. This consensus cep box has led to the identification of over 50 new genes potentially regulated by the CepIR quorum sensing system

    A combined geomorphological and geophysical approach to characterising relict landslide hazard on the Jurassic Escarpments of Great Britain

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    The Jurassic Escarpment in the North York Moors in Northern Britain has a high density of deep-seated relict landslides but their regional hazard is poorly understood due to a lack of detailed case studies. Investigation of a typical relict landslide at Great Fryup Dale suggests that the crop of the Whitby Mudstone Formation is highly susceptible to landslide hazards. The mudstone lithologies along the Escarpment form large multiple rotational failures which break down at an accelerated rate during wetter climates and degrade into extensive frontal mudflows. Geomorphological mapping, high resolution LiDAR imagery, boreholes, and geophysical ERT surveys are deployed in a combined approach to delimit internal architecture of the landslide. Cross-sections developed from these data indicate that the main movement displaced a bedrock volume of c. 1 × 107 m3 with a maximum depth of rupture of c. 50 m. The mode of failure is strongly controlled by lithology, bedding, joint pattern, and rate of lateral unloading. Dating of buried peats using the AMS method suggests that the 10 m thick frontal mudflow complex was last active in the Late Holocene, after c. 2270 ± 30 calendar years BP. Geomorphic mapping and dating work indicates that the landslide is dormant, but slope stability modelling suggests that the slope is less stable than previously assumed; implying that this and other similar landslides in Britain may become more susceptible to reactivation or extension during future wetter climatic phases. This study shows the value of a multi-technique approach for landslide hazard assessment and to enhance national landslide inventories

    Symptom management in people dying with COVID-19: multinational observational study

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    Objectives To describe multinational prescribing practices by palliative care services for symptom management in patients dying with COVID-19 and the perceived effectiveness of medicines.Methods We surveyed specialist palliative care services, contacted via relevant organisations between April and July 2020. Descriptive statistics for categorical variables were expressed as counts and percentages. Content analysis explored free text responses about symptom management in COVID-19. Medicines were classified using British National Formulary categories. Perceptions on effectiveness of medicines were grouped into five categories; effective, some, limited or unclear effectiveness, no effect.Results 458 services responded; 277 UK, 85 rest of Europe, 95 rest of the world, 1 missing country. 358 services had managed patients with confirmed or suspected COVID-19. 289 services had protocols for symptom management in COVID-19. Services tended to prescribe medicines for symptom control comparable to medicines used in people without COVID-19; mainly opioids and benzodiazepines for breathlessness, benzodiazepines and antipsychotics for agitation, opioids and cough linctus for cough, paracetamol and non-steroidal anti-inflammatory drugs for fever, and opioids and paracetamol for pain. Medicines were considered to be mostly effective but varied by patient’s condition, route of administration and dose.Conclusions Services were largely consistent in prescribing for symptom management in people dying with COVID-19. Medicines used prior to COVID-19 were mostly considered effective in controlling common symptoms
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