Sanfilippo D syndrome: Correction of glucosamine-6-sulphatase deficiency following fibroblast culture in chang's media

The de-O-sulphation of α-linked glucosamine-6-sulphate residues in heparan sulphate requires a specific sulphatase, glucosamine-6-sulphatase, which has been shown to be deficient in tissues of Sanfilippo D, or mucopolysaccharidosis type IIID (MPS IIID), patients. MPS IIID fibroblasts cultured in Basal Eagle's medium supplemented with either fetal calf serum or heat-inactivated fetal calf serum, MDCB or Ultraserg media had residual glucosarnine-6-sulphatase activities towards a heparin-derived trisaccharide substrate, O-(α-N-acetylglucosamine-6-sulphate)-(1→4)-L -O-(α-iduronic acid-2-sulphate)-(1→4)-D -O-2,5-anhydro [1-³H]mannitol-6-sulphate, GlcNAc6S-IdoA2S-anM6S, which were less than 1 per cent of the normal range for fibroblasts cultured in Basal Eagle's medium supplemented with fetal calf serum. However, the glucosamine-6-sulphatase activities of MPS IIID fibroblasts grown in Chang's medium were similar to the activities in normal control fibroblasts which were cultured in Basal Eagle's medium. These results indicate that caution is required for prenatal diagnosis of MPS IIID patients using chorionic villi or amniotic cells cultured in Chang's medium.     

TAXING NATURAL RESOURCE PROJECTS

A wide range of fiscal measures for natural resource based projects are analyzed in this paper. Maximizing government revenue involves taxing heavily any rents generated in the project while retaining the incentive to invest. Recovery efficiency must also be preserved. Based upon the principles of resource economics and project appraisai a series of tests are derived and applied to alternative tax schemes in order to assess their efficiency in maximizing the present value of government revenues. The tests indicate that of the ten schemes examined, the most likely to achieve revenue maximization is a progressive resource rent tax incorporating a safeguard tapering provision and superimposed upon normal corporate income tax. Many commonly applied taxes are demonstrated to have serious distortionary effects on the investment decision and to fail to capture a large proportion of rents generated. Cet article analyse une gamme variée de mesures fiscales applicables aux projets concernant les ressources naturelles. L'optimisation des recettes de l'Etat implique une lourde imposition des revenus provenant du projet tout en continuant à encourager les investissements. L'efficacité de la relance doit aussi être maintenue. Sur la base des principes de l'économie des ressources et de l'évaluation des projets, une série de tests a été conçue et appliquée à des systèmes fiscaux alternatifs afin de permettre l'évaluation de leur efficacité en ce qui concerne l'optimisation de la valeur actuelle des recettes de l'Etat. Les tests indiquent que sur les dix systèmes examinés, le plus susceptible d'optimiser les recettes semble être un impôt progressif sur les revenus provenant des ressources qui incorpore une clause de garantie dégressive et qui vient s'ajouter à l'impôt sur le revenu des sociétés habituel. L'article démontre que de nombreux impôts habituellement appliqués présentent de sérieux effets de distortion ayant un impact sur la décision d'investir et qu'une grande proportion des revenus de ces projets échappe à l'imposition. En este artículo se analiza una gama amplia de medidas fiscales sobre proyectos relacionados con recursos naturales. Maximizar los ingresos fiscales requiere imponer fuertes impuestos sobre las rentas generadas por el proyecto manteniendo al mismo tiempo el incentivo para la inversión. Debe mantenerse también la eficiencia en la recuperación de los recursos en cuestión. Basado en principios de la economía de recursos y de evaluación de proyectos se derivan una serie de pruebas sobre esquemas alternativos de aplicación de impuestos con el objeto de evaluar la eficiencia de dichos esquemas en la maximización del valor presente del ingreso del gobierno por concepto de impuestos. Las pruebas indican que de los diez esquemas examinados, el que con mayor probabilidad va a maximizar el ingreso del gobierno es el impuesto progresivo sobre la renta del recurso con un provisión de salvaguarda la reducción de dicho impuesto, más un impuesto simultáneo sobre el ingreso de la empresa. Muchos de los esquemas de imposición comúnmente aplicados tienen serios efectos distortionadores sobre las decisiones de inversión y consecuentamente impiden la colección de una gran parte de las rentas generadas.     

MODELING THE IMPACT OF MULTICOMPONENT VOCs ON GROUND WATER USING THE STEFAN‐MAXWELL EQUATION1

ABSTRACT: Computer programs that model the fate and transport of organic contaminants through porous media typically use Fick's first law to calculate vapor phase diffusion. Fick's first law, however, is limited to the case of a single, dilute species diffusing into a stagnant, high concentration, bulk vapor phase. When dealing with more than one diffusing species and at higher concentrations, the multicomponent coupling effects on vapor phase diffusion and advection of the various constituents become significant. VLEACH, a one‐dimensional finite difference model developed for the U.S. Environmental Protection Agency (USEPA), is typical of the models using Fick's first law to model vapor‐phase diffusion. The VLEACH model was modified to accommodate up to 10 components and to calculate the binary diffusion coefficients for each of the components based on molecular weight, molecular volume, temperature and pressure, and to address the coupling effects on multiple component vapor phase diffusion and its impact on ground water. The resulting model was renamed MC‐CHEMSOIL. At low vapor phase concentrations, MC‐CHEMSOIL predicts identical ground water impacts (dissolved phase loading) to those from VLEACH 2.2a. At higher vapor phase concentrations, however, the relative difference between the models exceeded 20 percent.     

Conservation implications of physiological carry‐over effects in bats recovering from white‐nose syndrome

Although it is well documented that infectious diseases can pose threats to biodiversity, the potential long‐term consequences of pathogen exposure on individual fitness and its effects on population viability have rarely been studied. We tested the hypothesis that pathogen exposure causes physiological carry‐over effects with a pathogen that is uniquely suited to this question because the infection period is specific and time limited. The fungus Pseudogymnoascus destructans causes white‐nose syndrome (WNS) in hibernating bats, which either die due to the infection while hibernating or recover following emergence from hibernation. The fungus infects all exposed individuals in an overwintering site simultaneously, and bats that survive infection during hibernation clear the pathogen within a few weeks following emergence. We quantified chronic stress during the active season, when bats are not infected, by measuring cortisol in bat claws. Free‐ranging Myotis lucifugus who survived previous exposure to P. destructans had significantly higher levels of claw cortisol than naïve individuals. Thus, cryptic physiological carry‐over effects of pathogen exposure may persist in asymptomatic, recovered individuals. If these effects result in reduced survival or reproductive success, they could also affect population viability and even act as a third stream in the extinction vortex. For example, significant increases in chronic stress, such as those indicated here, are correlated with reduced reproductive success in a number of species. Future research should directly explore the link between pathogen exposure and the viability of apparently recovered populations to improve understanding of the true impacts of infectious diseases on threatened populations.     

Response to lead pollution: mycorrhizal Pinus sylvestris forms the biomineral pyromorphite in roots and needles

Environmental Science and Pollution Research - The development of mycorrhized pine seedlings grown in the presence of lead was assessed in order to investigate how higher plants can tolerate lead...     

The Role of Disaggregation of Asset Values in Flood Loss Estimation: A Comparison of Different Modeling Approaches at the Mulde River,Germany

In loss estimation there is a spatial mismatch of hazard data that are commonly modeled on an explicit raster level and exposure data that are often available only for aggregated administrative units. Usually disaggregation methods that use ancillary information to distribute lumped exposure data in a finer spatial resolution help to bridge this gap. However, the actual influence of different mapping techniques and ancillary data on the final loss estimation has not been analyzed yet. In this paper three methods are applied to disaggregate residential building assets using two kinds of land use/land cover (LULC) data. The resulting disaggregated assets are validated and compared using census data of the residential building number on the community and constituency level. In addition, the disaggregated assets are taken to estimate residential building losses due to the flood in August 2002 in 21 municipalities on the River Mulde in Saxony, Germany. Losses are calculated with the help of four loss models. In general, disaggregation helps to decrease the error variance within the loss estimation. It must, however, be stated that the application of sophisticated disaggregation methods does not lead to significant improvements compared to the straightforward binary method. Therefore more effort should instead be put into the provision of high-resolution LULC data. Finally, the remaining uncertainties in loss estimation are high and demand further improvements in all modeling aspects.     

The use of technology to address patterns of risk among teenage drivers

INTRODUCTION: The crash risk of teens is high, with fatal crash rates of teen drivers higher than any other age group. New approaches to reduce teen traffic fatalities are clearly needed. METHOD: A possible approach to reduce the incidence of teen driver crashes and fatalities is through the use of vehicle-based intelligent driver support systems. To be most effective, the system should address the behaviors associated with an overwhelming number of teen fatal crashes: speed, low seatbelt use, and alcohol impairment. In-vehicle technology also offers an opportunity to address the issue of inexperience through enforcement of certain Graduated Driver's License provisions. RESULTS: To fully understand the capability of such technologies, there should be a concerted effort to further their development, and human factors testing should take place to understand their effects on the driver. IMPACT: If successfully implemented, a Teen Driver Support System (TDSS), such as the one described here, could significantly decrease the number of teens killed in traffic crashes.