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Potential Impact (potential + impact)
Selected AbstractsPOTENTIAL IMPACTS OF CLIMATE CHANGE ON CALIFORNIA HYDROLOGY,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2003Norman L. Miller ABSTRACT: Previous reports based on climate change scenarios have suggested that California will be subjected to increased wintertime and decreased summertime streamflow. Due to the uncertainty of projections in future climate, a new range of potential climatological future temperature shifts and precipitation ratios is applied to the Sacramento Soil Moisture Accounting Model and Anderson Snow Model in order to determine hydrologic sensitivities. Two general circulation models (GCMs) were used in this analysis: one that is warm and wet (HadCM2 run 1) and one that is cool and dry (PCM run B06.06), relative to the GCM projections for California that were part of the Third Assessment Report of the Intergovernmental Panel on Climate Change. A set of specified incremental temperature shifts from 1.5°C to 5.0°C and precipitation ratios from 0.70 to 1.30 were also used as input to the snow and soil moisture accounting models, providing for additional scenarios (e.g., warm/dry, cool/wet). Hydrologic calculations were performed for a set of California river basins that extend from the coastal mountains and Sierra Nevada northern region to the southern Sierra Nevada region; these were applied to a water allocation analysis in a companion paper. Results indicate that for all snow-producing cases, a larger proportion of the streamflow volume will occur earlier in the year. The amount and timing is dependent on the characteristics of each basin, particularly the elevation. Increased temperatures lead to a higher freezing line, therefore less snow accumulation and increased melting below the freezing height. The hydrologic response varies for each scenario, and the resulting solution set provides bounds to the range of possible change in streamflow, snowmelt, snow water equivalent, and the change in the magnitude of annual high flows. An important result that appears for all snowmelt driven runoff basins, is that late winter snow accumulation decreases by 50 percent toward the end of this century. [source] Assessing the Potential Impact of Cane Toads on Australian SnakesCONSERVATION BIOLOGY, Issue 6 2003BEN L. PHILLIPS Anecdotal reports suggest that the invasion of toads into an area is followed by dramatic declines in the abundance of terrestrial native frog-eating predators, but quantitative studies have been restricted to nonpredator taxa or aquatic predators and have generally reported minimal impacts. Will toads substantially affect Australian snakes? Based on geographic distributions and dietary composition, we identified 49 snake taxa as potentially at risk from toads. The impact of these feral prey also depends on the snakes' ability to survive after ingesting toad toxins. Based on decrements in locomotor (swimming) performance after ingesting toxin, we estimate the LD50 of toad toxins for 10 of the at-risk snake species. Most species exhibited a similar low ability to tolerate toad toxins. Based on head widths relative to sizes of toads, we calculate that 7 of the 10 taxa could easily ingest a fatal dose of toxin in a single meal. The exceptions were two colubrid taxa (keelbacks [ Tropidonophis mairii] and slatey-grey snakes [ Stegonotus cucullatus]) with much higher resistance to toad toxins (up to 85-fold) and one elapid (swamp snakes [ Hemiaspis signata]) with low resistance but a small relative head size and thus low maximum prey size. Overall, our analysis suggests that cane toads threaten populations of approximately 30% of terrestrial Australian snake species. Resumen: Los sapos (Bufo marinus) son anuros grandes muy tóxicos que fueron introducidos a Australia en 1937. Reportes anecdóticos sugieren que la invasión de sapos a un área es seguida de declinaciones dramáticas en la abundancia de depredadores terrestres nativos que se alimentan de ranas, pero los estudios cuantitativos se han restringido a taxones no depredadores o a depredadores acuáticos y generalmente han indicado impactos mínimos. ¿Los sapos afectarán sustancialmente a las serpientes australianas? Basado en la distribución geográfica y la composición de la dieta, identificamos 49 taxones de serpientes como potencialmente en riesgo por los sapos. El impacto de estas presas también depende de la habilidad de las serpientes para sobrevivir después de ingerir toxinas, estimamos la LD50 de toxinas de sapo para 10 de las especies de serpientes "en riesgo." La mayoría de las especies presentaron la misma poca habilidad para tolerar toxinas de sapo. Tomando en cuenta la anchura del cráneo en relación al tamaño de los sapos, calculamos que 7 de las 10 especies podrían fácilmente ingerir una dosis letal en una sola comida. Las excepciones fueron dos taxones de colúbridos (Tropidonophis mairii y Stegonotus cucullatus) con mucha más resistencia (hasta 85 veces más) a toxinas de sapos y un elápido (Hemiaspis signata) con resistencia baja pero de tamaño cefálico relativamente pequeño (y por lo tanto, tamaño máximo de presa pequeño). En general, nuestro análisis sugiere que los sapos amenazan a 30% de las poblaciones de especies de serpientes terrestres de Australia aproximadamente. [source] Potential Impact of Osteoporosis Treatment on Hip Fracture Trends,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2005L Joseph Melton III MD No abstract is available for this article. [source] Potential Impact of Adjusting the Threshold of the Quantitative D-dimer Based on Pretest Probability of Acute Pulmonary EmbolismACADEMIC EMERGENCY MEDICINE, Issue 4 2009Christopher Kabrhel MD Abstract Objectives:, The utility of D-dimer testing for suspected pulmonary embolism (PE) can be limited by test specificity. The authors tested if the threshold of the quantitative D-dimer can be varied according to pretest probability (PTP) of PE to increase specificity while maintaining a negative predictive value (NPV) of >99%. Methods:, This was a prospective, observational multicenter study of emergency department (ED) patients in the United States. Eligible patients had a diagnostic study ordered to evaluate possible PE. PTP was determined by the clinician's unstructured estimate and the Wells score. Five different D-dimer assays were used. D-dimer test performance was measured using 1) standard thresholds and 2) variable threshold values: twice (for low PTP patients), equal (intermediate PTP patients), or half (high PTP patients) of standard threshold. Venous thromboembolism (VTE) within 45 days required positive imaging plus decision to treat. Results:, The authors enrolled 7,940 patients tested for PE, and clinicians ordered a quantitative D-dimer for 4,357 (55%) patients who had PTPs distributed as follows: low (74%), moderate (21%), or high (4%). At standard cutoffs, across all PTP strata, quantitative D-dimer testing had a test sensitivity of 94% (95% confidence interval [CI] = 91% to 97%), specificity of 58% (95% CI = 56% to 60%), and NPV of 99.5% (95% CI = 99.1% to 99.7%). If variable cutoffs had been used the overall sensitivity would have been 88% (95% CI = 83% to 92%), specificity 75% (95% CI = 74% to 76%), and NPV 99.1% (95% CI = 98.7% to 99.4%). Conclusions:, This large multicenter observational sample demonstrates that emergency medicine clinicians currently order a D-dimer in the majority of patients tested for PE, including a large proportion with intermediate PTP and high PTP. Varying the D-dimer's cutoff according to PTP can increase specificity with no measurable decrease in NPV. [source] Climate Change Enhances the Potential Impact of Infectious Disease and Harvest on Tropical WaterfowlBIOTROPICA, Issue 4 2009Lochran W. Traill ABSTRACT Global warming exacerbates threats to biodiversity as ecological systems shift in response to altered climatic conditions. Yet the long-term survival of populations at direct risk from climate change may also be undermined by local factors such as infectious disease or anthropogenic harvest, which leave smaller and more isolated populations increasingly vulnerable to the rapid pace of global change. We review current and future threats to an exemplar tropical waterfowl species, magpie geese Anseranas semipalmata, and focus on the potential synergies between infectious diseases, harvest, and climate change. We outline viral, bacterial, and fungal pathogens likely to cause disease in geese, and give mention to parasites. Further, we elaborate on a previously developed, spatially explicit population viability model to simulate demographic responses to hunting and novel or enhanced disease outbreaks due to climate change. With no harvest, the simulated disease epizootics only threatened metapopulation viability when both mortality rate was high and outbreaks were regular (a threshold response). However, when contemporary site-specific harvest is included as an additive impact, the response to disease severity and probability was linear. We recommend field research to test these hypotheses linking drivers of waterfowl population decline to disease,climate change interactions. [source] Potential impact of a new blood glucose monitoring device: the GlucoWatch® BiographerPRACTICAL DIABETES INTERNATIONAL (INCORPORATING CARDIABETES), Issue 4 2002NN Chan Abstract Home blood glucose monitoring may be laborious, time-consuming, inconvenient and painful. Failure to test may preclude optimisation of glycaemic control. We aimed to evaluate the potential usefulness of a new noninvasive automatic glucose monitor, the GlucoWatch® Biographer. Eight patients with type 1 diabetes and two with type 2 diabetes (4M:6F) aged between 23 and 65 years participated in this study. All participants were given 1 hour of instruction prior to provision of the GlucoWatch®. They were given contact numbers and reviewed weekly. Several disadvantages were encountered by the participants, which included the daily 3 hour calibration period (n = 10), skin irritations (n = 6) and skipped measurements (n = 2) due to unsatisfactory probe contact due to skin temperature or sweats. Several patients, however, found it invaluable to have their daily profile monitored to allow insulin dosage adjustment and detection of hypoglycaemia. The GlucoWatch® Biographer is an invaluable tool that allows noninvasive detection of glucose trends, which contributes to glycaemic control. However, it is not suitable for every patient. Self-motivation and ability to learn how to use the device are the key factors. Copyright © 2002 John Wiley & Sons, Ltd. [source] Increasing the age of eligibility for receipt of aged pension in Australia: Potential impact on older peopleAUSTRALASIAN JOURNAL ON AGEING, Issue 3 2010Jean Woo No abstract is available for this article. [source] Potential impacts of climate change on Sub-Saharan African plant priority area selectionDIVERSITY AND DISTRIBUTIONS, Issue 6 2006Colin J. McClean ABSTRACT The Global Strategy for Plant Conservation (GSPC) aims to protect 50% of the most important areas for plant diversity by 2010. This study selects sets of 1-degree grid cells for 37 sub-Saharan African countries on the basis of a large database of plant species distributions. We use two reserve selection algorithms that attempt to satisfy two of the criteria set by the GSPC. The grid cells selected as important plant cells (IPCs) are compared between algorithms and in terms of country and continental rankings between cells. The conservation value of the selected grid cells are then considered in relation to their future species complement given the predicted climate change in three future periods (2025, 2055, and 2085). This analysis uses predicted climate suitability for individual species from a previous modelling exercise. We find that a country-by-country conservation approach is suitable for capturing most, but not all, continentally IPCs. The complementarity-based reserve selection algorithms suggest conservation of a similar set of grid cells, suggesting that areas of high plant diversity and rarity may be well protected by a single pattern of conservation activity. Although climatic conditions are predicted to deteriorate for many species under predicted climate change, the cells selected by the algorithms are less affected by climate change predictions than non-selected cells. For the plant species that maintain areas of climatic suitability in the future, the selected set will include cells with climate that is highly suitable for the species in the future. The selected cells are also predicted to conserve a large proportion of the species richness remaining across the continent under climate change, despite the network of cells being less optimal in terms of future predicted distributions. Limitations to the modelling are discussed in relation to the policy implications for those implementing the GSPC. [source] Potential impacts on the incidence of fatal heroin-related overdose in Western Australia: a time-series analysisDRUG AND ALCOHOL REVIEW, Issue 4 2002KIM HARGREAVES Abstract In response to the rising concerns about the rate of heroin-related fatalities, overdose prevention campaigns, run by both users' organizations and government agencies, have been implemented in a number of states across Australia. In Western Australia (WA) in mid-1997, various overdose prevention initiatives were implemented. These included the implementation of a protocol limiting police presence at overdose events; the commencement of naloxone administration by ambulance staff; and the establishment of the Opiate Overdose Prevention Strategy (OOPS) which provided follow-up for individuals treated for overdose in emergency departments. This paper reports the results of a multiple linear regression analysis of 60 months of time-series data, both prior to and following the implementation of these interventions, to determine their impact on the number of fatal heroin overdoses in WA. The model employed in the analysis controlled for changes over time in proxy indicators of use and community concerns about heroin, as well as market indicators. The results suggest that, although the interventions implemented have managed to reduce the expected number of fatalities, they have become less successful in doing so as time passes. This has implications for both existing and potential interventions to reduce fatal heroin-related overdose. [source] Voracious invader or benign feline?FISH AND FISHERIES, Issue 3 2009A review of the environmental biology of European catfish Silurus glanis in its native, introduced ranges Abstract A popular species for food and sport, the European catfish (Silurus glanis) is well-studied in its native range, but little studied in its introduced range. Silurus glanis is the largest-bodied freshwater fish of Europe and is historically known to take a wide range of food items including human remains. As a result of its piscivorous diet, S. glanis is assumed to be an invasive fish species presenting a risk to native species and ecosystems. To assess the potential risks of S. glanis introductions, published and ,grey' literature on the species' environmental biology (but not aquaculture) was extensively reviewed. Silurus glanis appears well adapted to, and sufficiently robust for, translocation and introduction outside its native range. A nest-guarding species, S. glanis is long-lived, rather sedentary and produces relatively fewer eggs per body mass than many fish species. It appears to establish relatively easily, although more so in warmer (i.e. Mediterranean) than in northern countries (e.g. Belgium, UK). Telemetry data suggest that dispersal is linked to flooding/spates and human translation of the species. Potential impacts in its introduced European range include disease transmission, hybridization (in Greece with native endemic Aristotle's catfish [Silurus aristotelis]), predation on native species and possibly the modification of food web structure in some regions. However, S. glanis has also been reported (France, Spain, Turkmenistan) to prey intensively on other non-native species and in its native Germany to be a poor biomanipulation tool for top-down predation of zooplanktivorous fishes. As such, S. glanis is unlikely to exert trophic pressure on native fishes except in circumstances where other human impacts are already in force. In summary, virtually all aspects of the environmental biology of introduced S. glanis require further study to determine the potential risks of its introduction to novel environments. [source] Potential impacts of projected sea-level rise on sea turtle rookeriesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2010MMPB Fuentes Abstract 1.Projected sea-level rise (SLR) is expected to cause shoreline erosion, saline intrusion into the water table and inundation and flooding of beaches and coastal areas. Areas most vulnerable to these physical impacts include small, tropical low-lying islands, which are often key habitat for threatened and endemic species, such as sea turtles. 2.Successful conservation of threatened species relies upon the ability of managers to understand current threats and to quantify and mitigate future threats to these species. This study investigated how sea-level rise might affect key rookeries (nesting grounds) (n=8) for the northern Great Barrier Reef (nGBR) green turtle population, the largest green turtle population in the world. 3.3-D elevation models were developed and applied to three SLR scenarios projected by the IPCC 2007 and an additional scenario that incorporates ice melting. Results indicate that up to 38% of available nesting area across all the rookeries may be inundated as a result of SLR. 4.Flooding, as a result of higher wave run-up during storms, will increase egg mortality at these rookeries affecting the overall reproductive success of the nGBR green turtle population. Information provided will aid managers to prioritize conservation efforts and to use realistic measures to mitigate potential SLR threats to the nGBR green turtle population. Copyright © 2009 John Wiley & Sons, Ltd. [source] Significance of Modeling Error in Structural Parameter EstimationCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2001Masoud Sanayei Structural health monitoring systems rely on algorithms to detect potential changes in structural parameters that may be indicative of damage. Parameter-estimation algorithms seek to identify changes in structural parameters by adjusting parameters of an a priori finite-element model of a structure to reconcile its response with a set of measured test data. Modeling error, represented as uncertainty in the parameters of a finite-element model of the structure, curtail capability of parameter estimation to capture the physical behavior of the structure. The performance of four error functions, two stiffness-based and two flexibility-based, is compared in the presence of modeling error in terms of the propagation rate of the modeling error and the quality of the final parameter estimates. Three different types of parameters are used in the parameter estimation procedure: (1) unknown parameters that are to be estimated, (2) known parameters assumed to be accurate, and (3) uncertain parameters that manifest the modeling error and are assumed known and not to be estimated. The significance of modeling error is investigated with respect to excitation and measurement type and locations, the type of error function, location of the uncertain parameter, and the selection of unknown parameters to be estimated. It is illustrated in two examples that the stiffness-based error functions perform significantly better than the corresponding flexibility-based error functions in the presence of modeling error. Additionally, the topology of the structure, excitation and measurement type and locations, and location of the uncertain parameters with respect to the unknown parameters can have a significant impact on the quality of the parameter estimates. Insight into the significance of modeling error and its potential impact on the resulting parameter estimates is presented through analytical and numerical examples using static and modal data. [source] The Measurement of Daily Surge and Its Relevance to Disaster PreparednessACADEMIC EMERGENCY MEDICINE, Issue 11 2006Melissa L. McCarthy MS This article reviews what is known about daily emergency department (ED) surge and ED surge capacity and illustrates its potential relevance during a catastrophic event. Daily ED surge is a sudden increase in the demand for ED services. There is no well-accepted, objective measure of daily ED surge. The authors propose that daily and catastrophic ED surge can be measured by the magnitude of the surge, as well as by the nature and severity of the illnesses and injuries that patients present with during the surge. The magnitude of an ED surge can be measured by the patient arrival rate per hour. The nature and severity of the surge can be measured by the type (e.g., trauma vs. infection vs. biohazard) and acuity (e.g., triage level) of the surge. Surge capacity is defined as the extent to which a system can respond to a rapid and sizeable increase in the demand for resources. ED surge capacity includes multiple dimensions, such as systems, space, staffing, and supplies. A multidimensional measure is needed that reflects both the core components and their relative contribution to ED surge capacity. Although many types of factors may influence ED surge capacity, relatively little formal research has been conducted in this area. A better understanding of daily ED surge capacity and influencing factors will improve our ability to simulate the potential impact that different types of catastrophic events may have on the surge capacity of hospital EDs nationwide. [source] Trials update in walesCYTOPATHOLOGY, Issue 2007A. Fiander Three ongoing studies will be presented and discussed. Prevalence of Human Papillomavirus Infection in a South Wales Screening population Methods: A total of 10 000 consecutive, anonymous liquid based cytology screening samples were collected over a five month period in 2004. Age, cytology result and social deprivation score was provided for each specimen. The methodology was chosen to ensure inclusion of all women attending routine cervical screening, avoiding potential constraints associated with obtaining individual informed consent. The liquid based cytology samples were processed and reported by the receiving cytology laboratory and the residual specimens sent to the HPV Research Laboratory, Wales College of Medicine, where they were processed and stored at -80°C until analysis. High risk and low risk HPV Typing was undertaken using PCR , EIA (Jacobs et al 1997). Full high risk typing was performed on HPV positive specimens. Results: The study population had a mean age of 38 years with 92% negative, 5% borderline and 3% dyskaryotic cytology. The average social deprivation score was 17.4 (based upon the Welsh Index of multiple deprivation). The following results will be presented: HPV prevalence by age. HPV prevalence by cytology result. Type specific HPV prevalence in single and multiple infection. Conclusion: This study represents the largest type specific HPV Prevalence Study in the UK to date. As such it will form a useful base line against which to access performance of marketed HPV tests and evaluating the impact following implementation of HPV vaccination. [Funded by Welsh Office for Research and Development] CRISP , 1 Study (Cervical Randomized Intervention Study Protocol -1) Background: Indole-3-carbinol (I3C) and Diindolylmethane (DIM) are found in cruciferous vegetables and have been identified as compounds that could potentially prevent or halt carcinogenesis. I3C spontaneously forms DIM in vivo during acid digestion. I3C has been shown to prevent the development of cervical cancer in HPV 16 transgenic mice and both I3C and DIM have been shown to promote cell death in cervical cancer cell models. DIM is the major active bi-product of I3C and preliminary data indicate that DIM is active in cervical dysplasia and may be better tolerated than I3C. Aim: To investigate chemoprevention of high grade cervical neoplasia using Diindolylmethane (DIM) supplementation in women with low grade cytological abnormalities on cervical cytology. Objectives: To observe any reduction in the prevalence of histological proven high-grade cervical intraepithelial neoplasia (CIN) after 6 months of supplementation. ,,To observe any reduction in the prevalence of cytological abnormalities. ,,To observe any changes in the clinical appearance of the cervix. To assess acceptability and monitor any side effects of DIM supplementation. ,,To assess whether any benefit is seen in relation to Human Papillomavirus (HPV) status including HPV Type, Viral load and integration. Methods: This is a double blind randomized placebo-controlled trial involving 600,700 women with low grade cytological abnormalities on a cervical smear. Randomization is in the ratio of 2 : 1 in favour of active medication. Women with first mildly dyskaryotic smear or second borderline smear are eligible. They are asked to take two capsules daily for 6 months. At the end of 6 months they undergo repeat cervical cytology, HPV testing and colposcopy. Results: A progress report will be given for this ongoing study. [Funded: - Cancer Research UK] Type Specific HPV Infection in Welsh Cervical Cancers Background: Whilst there have been numerous studies of HPV infection associated with cervical cancer and on prevalence of Human Papillomavirus in diverse populations there have been no studies of these variables in the same population. Against a background of prophylactic HPV vaccination it is important to assess potential protection against cervical cancer within a given population. The most comprehensive analysis of HPV type specific cervical cancer is a meta-analysis published by the IARC in 2003. This however included only three UK based studies, totalling 118 cases, 75 of which were only investigated by HPV type PCR for four high risk types. None of this data was presented with associated population based prevalence data. Therefore, the research objectives for this study in combination with the first study above, are as follows: To determine the frequency of specific HPV types in cervical cancers in Wales. To compare the distribution of specific HPV types amongst cervical cancers with their prevalence in the general population. This will allow accurate delineation of the relationship between prevalence of specific HPV types in the general population and their association with clinically relevant disease. This information is a pre-requisite to assess the potential impact of prophylactic vaccination against HPV infection in Wales. Methods: Welsh Cervical Cancer specimens from 2000,2005 will be identified from pathology departments within Wales. The pathology of each tumour will be reviewed by a single Gynaecological Pathologist. The age of the patient and pathological features of the tumour will be noted. DNA will be extracted from the paraffin sections and HPV typed by PCR-EIA. Results: A progress report will be given for this ongoing study. [Funded by Welsh Office for Research and Development] [source] Investment and Competition Policy in the WTO: Issues for Developing CountriesDEVELOPMENT POLICY REVIEW, Issue 1 2002Oliver Morrissey This article uses the case of trade-related investment measures (TRIMs) to examine the liberalisation of investment and its potential impact on developing countries. Very few developing countries actually use TRIMs to any appreciable degree, but, when taken in conjunction with the broader liberalisation of investment, the 1994 TRIMs Agreement has significant implications that will constrain governments' policy options and require issues of competition policy to be addressed. Multilateral competition policy would be difficult to agree and implement and the article considers alternative strategies that developing countries could adopt. [source] Incorrect and incomplete coding and classification of diabetes: a systematic reviewDIABETIC MEDICINE, Issue 5 2010M. A. Stone Diabet. Med. 27, 491,497 (2010) Abstract Aims, To conduct a systematic review to identify types and implications of incorrect or incomplete coding or classification within diabetes or between diabetes and other conditions; also to determine the availability of evidence regarding frequency of occurrence. Methods, Medical Subject Headings (MeSH) and free-text terms were used to search relevant electronic databases for papers published to the end of August 2008. Two researchers independently reviewed titles and abstracts and, subsequently, the full text of potential papers. Reference lists of selected papers were also reviewed and authors consulted. Three reviewers independently extracted data. Results, Seventeen eligible studies were identified, including five concerned with distinguishing between Type 1 and Type 2 diabetes. Evidence was also identified regarding: the distinction between diabetes and no-diabetes, failure to specify type of diabetes, and diagnostic errors or difficulties involving maturity-onset diabetes of the young, latent autoimmune diabetes in adults, pancreatic diabetes, persistence of foetal haemoglobin and acquired immune deficiency syndrome (AIDS). The sample was too heterogeneous to derive accurate information about frequency, but our findings suggested that misclassification occurs most commonly in young people. Implications relating to treatment options and risk management were highlighted, in addition to psychological and financial implications and the potential impact on the validity of quality of care evaluations and research. Conclusions, This review draws attention to the occurrence and implications of incorrect or incomplete coding or classification of diabetes, particularly in young people. A pragmatic and clinically relevant approach to classification is needed to assist those involved in making decisions about types of diabetes. [source] Studies of associations between the Arg389Gly polymorphism of the ,1 -adrenergic receptor gene (ADRB1) and hypertension and obesity in 7677 Danish white subjectsDIABETIC MEDICINE, Issue 4 2007A. P. Gjesing Abstract Aims, Activation of the ,1 -adrenergic receptor (ADRB1) causes increased lipolysis in adipose tissue and enhances cardiac output. Analysis of the association of the functional ADRB1 Arg389Gly variant with obesity and hypertension has given ambiguous results. To clarify the potential impact of this variant on obesity and hypertension in the general population, we examined the Arg389Gly variant in a relatively large-scale population-based study. Methods, Case-control studies and quantitative trait analyses were carried out in 7677 Danish Caucasians who were genotyped for the Arg389Gly variant (dbSNP rs1801253) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Results, A weak association between the Gly allele of the Arg389Gly variant and obesity was observed when comparing cases (n = 1540) defined as body mass index (BMI) > 30 kg/m2 with control subjects (n = 6108) defined as BMI , 30 kg/m2 for both allele frequencies (P = 0.05) and genotype distribution (P = 0.05). Case-control studies (cases n = 2518; control n = 3981) examining the effect on hypertension showed no association with allele frequencies (P = 0.3) or genotype distribution (P = 0.5); however, in the quantitative trait analyses, individuals carrying the Gly allele had slightly but significantly lower diastolic (Arg/Arg = 81.9 mmHg vs. Gly-allele carriers = 81.5 mmHg) and systolic (Arg/Arg = 129.4 mmHg vs. Gly-allele carriers = 128.8 mmHg) blood pressure as well as a lower mean arterial blood pressure. Conclusion, Our results suggest that the Arg389Gly polymorphism does not have any clinically important impact on the pathogenesis of obesity in Danish white subjects. Furthermore, despite the observed minor influence on blood pressure, this variant is most likely not to be a major contributor to the development of hypertension. [source] The Validity of Using Multiple Imputation for Missing Out-of-hospital Data in a State Trauma RegistryACADEMIC EMERGENCY MEDICINE, Issue 3 2006Craig D. Newgard MD Objectives: To assess 1) the agreement of multiply imputed out-of-hospital values previously missing in a state trauma registry compared with known ambulance values and 2) the potential impact of using multiple imputation versus a commonly used method for handling missing data (i.e., complete case analysis) in a typical multivariable injury analysis. Methods: This was a retrospective cohort analysis. Multiply imputed out-of-hospital data from 1998 to 2003 for four variables (intubation attempt, Glasgow Coma Scale score, systolic blood pressure, and respiratory rate) were compared with known values from probabilistically linked ambulance records using measures of agreement (,, weighted ,, and Bland,Altman plots). Ambulance values were assumed to represent the "true" values for all analyses. A hypothetical multivariable regression model was used to demonstrate the impact (i.e., bias and precision of model results) of handling missing out-of-hospital data with multiple imputation versus complete case analysis. Results: A total of 6,150 matched ambulance and trauma registry records were available for comparison. Multiply imputed values for the four out-of-hospital variables demonstrated fair to good agreement with known ambulance values. When included in typical multivariable analyses, multiple imputation increased precision and reduced bias compared with using complete case analysis for the same data set. Conclusions: Multiply imputed out-of-hospital values for intubation attempt, Glasgow Coma Scale score, systolic blood pressure, and respiratory rate have fair to good agreement with known ambulance values. Multiple imputation also increased precision and reduced bias compared with complete case analysis in a typical multivariable injury model, and it should be considered for studies using out-of-hospital data from a trauma registry, particularly when substantial portions of data are missing. [source] Why is the choice of future climate scenarios for species distribution modelling important?ECOLOGY LETTERS, Issue 11 2008Linda J. Beaumont Abstract Species distribution models (SDMs) are common tools for assessing the potential impact of climate change on species ranges. Uncertainty in SDM output occurs due to differences among alternate models, species characteristics and scenarios of future climate. While considerable effort is being devoted to identifying and quantifying the first two sources of variation, a greater understanding of climate scenarios and how they affect SDM output is also needed. Climate models are complex tools: variability occurs among alternate simulations, and no single ,best' model exists. The selection of climate scenarios for impacts assessments should not be undertaken arbitrarily - strengths and weakness of different climate models should be considered. In this paper, we provide bioclimatic modellers with an overview of emissions scenarios and climate models, discuss uncertainty surrounding projections of future climate and suggest steps that can be taken to reduce and communicate climate scenario-related uncertainty in assessments of future species responses to climate change. [source] Plant,soil feedbacks and invasive spreadECOLOGY LETTERS, Issue 9 2006Jonathan M. Levine Abstract Plant invaders have been suggested to change soil microbial communities and biogeochemical cycling in ways that can feedback to benefit themselves. In this paper, we ask when do these feedbacks influence the spread of exotic plants. Because answering this question is empirically challenging, we show how ecological theory on ,pushed' and ,pulled' invasions can be used to examine the problem. We incorporate soil feedbacks into annual plant invasion models, derive the conditions under which such feedbacks affect spread, and support our approach with simulations. We show that in homogeneous landscapes, strong positive feedbacks can influence spreading velocity for annual invaders, but that empirically documented feedbacks are not strong enough to do so. Moreover, to influence spread, invaders must modify the soil environment over a spatial scale larger than is biologically realistic. Though unimportant for annual invader spread in our models, feedbacks do affect invader density and potential impact. We discuss how future research might consider the way landscape structure, dispersal patterns, and the time scales over which plant,soil feedbacks develop regulate the effects of such feedbacks on invader spread. [source] Nation to Nation: Defining New Structures of Development in Northern QuebecECONOMIC GEOGRAPHY, Issue 4 2004Caroline Desbiens Abstract: In February 2002, the Crees of Quebec and the Quebec government signed a new agreement that was designed to implement new structures of economic development in northern Quebec. The document, known as "La Paix des Braves" (Peace of the Braves), was characterized as a "nation-to-nation" agreement and promises greater participation by the Crees in the management and exploitation of natural resources on the territory. Starting from the premise that the Crees and the Québécois do not simply compete for the resources of James Bay but can be said to define and firm up the boundaries of their respective nation in and through the use of these resources, this article explores the close intertwining of colonialism, culture, and the economy in James Bay, as well as its potential impact on the new agreement. First, it analyzes how the Crees and the Québécois have articulated nationhood in relation to land and resources, particularly over the past three decades. Second, it examines how these discourses are informed by a third national scale, that of Canada. The intersection among nature, nation, and economic development in northern Quebec is a key example of how resources are embedded in complex national geographies that are shaped across a broad historical span. Although sustainability is often defined in terms of the needs of future generations, this article calls for greater attention to past colonial and political relations in defining structures of development that ensure the renewal of resources. [source] The ttgGHI solvent efflux pump operon of Pseudomonas putida DOT-T1E is located on a large self-transmissible plasmidENVIRONMENTAL MICROBIOLOGY, Issue 6 2007José J. Rodríguez-Herva Summary Pseudomonas putida DOT-T1E is a solvent-tolerant strain able to grow in the presence of > 1% (v/v) toluene in the culture medium. A set of multidrug efflux pumps have been found to play a major role in the tolerance of this bacterium to organic solvents (Rojas et al., J Bacteriol 183: 3967,3973). In the course of studies of the mechanisms underlying solvent tolerance in DOT-T1E, we isolated a spontaneous solvent-sensitive mutant derivative which had lost the genes encoding the TtgGHI efflux pump, the most important extrusion element in quantitative terms. Genomic comparisons between the mutant and its parental strain by microarray analysis revealed that in addition to the ttgVW-ttgGHI gene cluster, another group of genes, highly similar to those found in the Tn4653A and ISPpu12 transposable elements of the TOL plasmid pWW0 from P. putida mt-2, were also absent from this strain. Further analysis demonstrated that strain DOT-T1E harboured a large plasmid (named pGRT1) that was lost from the solvent-sensitive mutant. Mapping analysis revealed that the ttgVW-ttgGHI genes and the Tn4653A -like transposon are borne by the pGRT1 plasmid. Plasmid pGRT1 is highly stable and its frequency of loss is below 10,8 per cell per generation under a variety of growth conditions, including nutritional and physical stresses. The pGRT1 plasmid is self-transmissible, and its acquisition by the toluene-sensitive P. putida KT2440 and Pseudomonas aeruginosa PAO1 increased the recipient's tolerance to toluene up to levels similar to those exhibited by P. putida DOT-T1E. We discuss the importance and potential benefits of this plasmid for the development of bacteria with enhanced solvent tolerance, and its potential impact for bioremediation and whole-cell biotransformations. [source] Contaminated suspended sediments toxic to an Antarctic filter feeder: Aqueous- and particulate-phase effectsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2009Nicole A. Hill Abstract Disturbances such as dredging, storms, and bioturbation result in the resuspension of sediments. This may affect sessile organisms that live on hard substrates directly above the sediment. Localized sediment contamination exists around many Antarctic research stations, often resulting in elevated contamination loads in marine sediments. To our knowledge, the potential impact of resuspended contaminated sediments on sessile fauna has not been considered, so in the present study, we assessed the sensitivity of Antarctic spirorbid polychaetes to aqueous metals and to metal-contaminated sediments that had been experimentally resuspended. Worms were first exposed to aqueous metals, both singly and in combination, over 10 d. Spirorbid mortality was tolerant to copper (median lethal concentration [LC50], 570 ,g/L), zinc (LC50, >4,910 ,g/L), and lead (LC50, >2,905 ,g/L); however, spirorbid behavior responded to copper concentrations as low as 20,g/L. When in combination, zinc significantly reduced mortality caused by copper. A novel technique was used to resuspend sediments spiked with four concentrations of three metals (up to 450 ,g/g dry wt of copper, 525 ,g/g dry wt of lead, and 2,035 ,g/g dry wt of zinc). The response of spirorbids to unfiltered suspended sediment solutions and filtered solutions (aqueous metal exposure) was measured. Suspended sediments were toxic to filter-feeding spirorbids at concentrations approximating those found in contaminated Antarctica areas. Toxicity resulted both from aqueous metals and from metals associated with the suspended sediments, although suspended clean sediments had no impact. To our knowledge, the present study is the first to show that resuspension of contaminated sediments can be an important pathway for toxicity to Antarctic hard substrate organisms. Based on the present results, current sediment-quality guidelines used in the evaluation of Australian sediments may be applicable to Antarctic ecosystems. [source] Molecular modeling of metal complexation by a fluoroquinolone antibioticENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2008Ludmilla Aristilde Abstract An understanding of the factors controlling the chemodynamics of fluoroquinolone antibiotics in different environmental matrices is a necessary prerequisite to the assessment of their potential impact on nontarget organisms in soils and receiving waters. Of particular interest are the complexes formed between fluoroquinolones and metal cations, which are believed to be important in the mechanism of sequestration of the antibiotic by minerals and natural organic matter. The structures of these complexes have not been fully resolved by conventional spectroscopy; therefore, molecular simulations may provide useful complementary insights. We present results from apparently the first molecular dynamics simulations of a widely used fluoroquinolone antibiotic, ciprofloxacin (Cipro), in aqueous complexes with five metal cations typically found in soils and surface waters: Ca2+, Mg2+, Fe2+, Na+, and K+. The interatomic potential functions employed in the simulations were validated by comparison with available structural data for solid-phase Cipro-hexahydrate and for the metal cations in aqueous solution. Although no comprehensive structural data on the aqueous complexes appear to be available, properties of the metal complexes predicted by our simulations agree with available data for solid-phase metal,Cipro complexes. Our results indicate that the ionic potential of the metal cation controls the stability of the complex formed and that the hydration number of the metal cation in aqueous solution determines its coordination number with O atoms in the metal,Cipro complex. In respect to environmental chemodynamics, our results imply that Cipro will form two configurations of bidendate chelates with metal centers on exposed surfaces of mineral oxides, water-bridged surface complexes with exchangeable cations in clay mineral interlayers, and cation-bridged complexes with functional groups in natural organic matter. [source] Assessing the impacts of grazing levels on bird density in woodland habitat: a Bayesian approach using expert opinionENVIRONMETRICS, Issue 7 2005Petra M. Kuhnert Abstract Many studies on birds focus on the collection of data through an experimental design, suitable for investigation in a classical analysis of variance (ANOVA) framework. Although many findings are confirmed by one or more experts, expert information is rarely used in conjunction with the survey data to enhance the explanatory and predictive power of the model. We explore this neglected aspect of ecological modelling through a study on Australian woodland birds, focusing on the potential impact of different intensities of commercial cattle grazing on bird density in woodland habitat. We examine a number of Bayesian hierarchical random effects models, which cater for overdispersion and a high frequency of zeros in the data using WinBUGS and explore the variation between and within different grazing regimes and species. The impact and value of expert information is investigated through the inclusion of priors that reflect the experience of 20 experts in the field of bird responses to disturbance. Results indicate that expert information moderates the survey data, especially in situations where there are little or no data. When experts agreed, credible intervals for predictions were tightened considerably. When experts failed to agree, results were similar to those evaluated in the absence of expert information. Overall, we found that without expert opinion our knowledge was quite weak. The fact that the survey data is quite consistent, in general, with expert opinion shows that we do know something about birds and grazing and we could learn a lot faster if we used this approach more in ecology, where data are scarce. Copyright © 2005 John Wiley & Sons, Ltd. [source] Occurrence, ecology and potential impact of the New Zealand wheat bug Nysius huttoni White (Hemiptera: Lygaeidae) in BelgiumEPPO BULLETIN, Issue 2 2010J. Bonte In 2002 the New Zealand wheat bug Nysius huttoni White was observed for the first time in the Netherlands and Belgium. The introduction of N. huttoni to these regions presumably occurred via overseas transport of apple and kiwi fruits from New Zealand. Laboratory experiments showed that both eggs and adults of N. huttoni were capable of surviving cold conditions similar to those in overseas transportation. Specimens were sampled in Belgium and the Netherlands, and a DNA sequence analysis indicated a 100% similarity with N. huttoni material collected in Christchurch, New Zealand. The distribution of the lygaeid in Belgium in 2008 was studied based on a systematic sampling at 105 locations. The bug had been able to spread over most of the Belgian territory, with the exception of the most southern and eastern provinces. Given the poor flight capacity of Belgian N. huttoni populations, other methods of dispersal may be involved. N. huttoni occurred primarily in ruderal habitats, and its weedy host plants belong to very common plant families. Several observations support N. huttoni not being a threat for agricultural crops in Belgium under the present conditions of climate and soil usage. [source] Supply control and harm reduction: lessons from the Australian heroin ,drought'ADDICTION, Issue 1 2003Don Weatherburn ABSTRACT Aims, To examine the effects of supply-side drug law enforcement on the dynamics of the Australian heroin market and the harms associated with heroin. Setting, Around Christmas 2000, heroin users in Sydney and other large capital cities in Australia began reporting sudden and significant reductions in the availability of heroin. The changes, which appear to have been caused at least in part by drug law enforcement, provided a rare opportunity to examine the potential impact of such enforcement on the harm associated with heroin. Design, Data were drawn from a survey of 165 heroin users in South-Western Sydney, Australia; from the Drug Use Monitoring in Australia (DUMA) project; from NSW Health records of heroin overdoses; and from the Computerized Operational Policing System (COPS) database. Findings, Heroin price increased, while purity, consumption and expenditure on the drug decreased as a result of the shortage. The fall in overall heroin use was accompanied by a significant reduction in the rate of overdose in NSW. However, the health benefits associated with the fall in overdose may have been offset by an increase in the use of other drugs (mainly cocaine) since the onset of the heroin shortage. There does not appear to have been any enduring impact on crime rates as a result of the heroin ,drought'. Conclusion, Supply control has an important part to play in harm reduction; however, proponents of supply-side drug law enforcement need to be mindful of the unintended adverse consequences that might flow from successfully disrupting the market for a particular illegal drug. [source] Clinical impact of FDG-PET/CT in the planning of radiotherapy for early-stage Hodgkin lymphomaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2007Martin Hutchings Abstract Background:,Early-stage Hodgkin lymphoma (HL) has excellent survival rates but carries a high risk of late treatment-related adverse effects. Modern, individualised therapeutic strategies require an accurate determination of the extent of the disease. This study investigated the potential impact of 2-[18F]-fluoro-2-deoxy- d -glucose positron emission tomography/computerised tomogrpahy (FDG-PET/CT) in the planning of involved field radiotherapy (IFRT). Patients and methods:,Thirty patients received staging FDG-PET/CT before therapy, and IFRT after a short course of ABVD (adriamycin, bleomycin, vinblastine, dacarbazine) chemotherapy. IFRT planning was performed using only the CT data from the FDG-PET/CT scan. Later, the IFRT planning was performed anew using the FDG-PET/CT data as basis for contouring. Results:,In 20 out of 30 patients, the radiotherapy (RT) course was unaffected by the addition of FDG-PET/CT. FDG-PET/CT would have increased the irradiated volume in seven patients where the volume receiving a minimum of 90% of the target dose was increased by 8,87%. FDG-PET/CT decreased the volume in two patients where the volume was reduced by 18% and 30%. Conclusions:,When used for RT planning, FDG-PET/CT results in larger IFRT treatment volumes. If FDG-PET/CT is introduced to RT planning, the method should be accompanied by a change in RT treatment strategy, aiming at more targeted therapy in order to best avoid radiation to normal tissues. [source] Identification of organic eluates from four polymer-based dental filling materialsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2003Vibeke Barman Michelsen Elution from polymer-based dental filling materials may have a potential impact on the biocompatibility of the materials. Since information from the manufacturers about ingredients in the materials often is incomplete, analyses of eluates from the materials are necessary for a better knowledge about possible harmful compounds. The aim of this study was to identify organic eluates from polymerized samples of two composites, one compomer and one resin-reinforced glass ionomer cement. Samples were immersed in ethanol or Ringer's solution. Organic leachables were analyzed by gas chromatography,mass spectrometry. Identification was confirmed with reference substances, if available. Among components detected were monomers, co-monomers, initiators, stabilizers, decomposition products and contaminants. Thirty-two substances were identified and 17 were confirmed with reference substances. From elution in Ringer's we identified 13 eluates from Tetric Ceram, 10 from Z250, 21 from Dyract and six from Fuji II LC; HEMA, HC and CQ were found in all samples. From elution in ethanol 12 eluates from Tetric Ceram, 18 eluates from Z250, 19 from Dyract and 10 from Fuji II LC were identified. The diversity of eluates from the four materials under study is demonstrated. Owing to variation between the materials, the biocompatibility including the allergenic potential may be different. [source] Governmental participation and the organizational adaptation of Green parties: On access, slack, overload and distressEUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 2006BENOÎT RIHOUX On the one hand, a series of hypotheses with regards to the possible link between prior organizational adaptation and eventual access to governmental participation are examined. On the other, the opposite question is addressed: that of the potential impact of governmental participation , and, more recently, exit from government , on further organizational adaptation. Following both a qualitative and a qualitative comparative (QCA) analysis, one ultimately identifies a link between prior organizational adaptation and eventual access to government, but a much more indirect and contrasted link between governmental participation (and exit from government) and further organizational adaptation. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||