956 resultados para Linear and Quadratic Complexity Bounds on the Values of the Positive Roots
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South Florida has been subject to considerable changes during the last 100 years. This study provides a detailed survey of the presence, concentration levels, and spatial distribution of organic and inorganic contaminants in sediment samples collected within the coastal environments of southwest Florida. It evaluates the potential contributions and effects of the urban and agricultural development to the pollution loading of the estuarine sediments. And it also provides information regarding chronology of contamination at impacted sites. Copper was found to be the most critical contaminant among the trace metals. 12% of the samples exceeded the Threshold Effects Level (TEL). None of organic contaminants measured exceeded the Probable Effects Level (PEL) criteria. Total PAHs concentrations exceeded the TEL criteria in 6% of the samples. The evaluation for the chronology of contamination showed a significant increase with time of every contaminant analyzed. Fluorescence spectroscopy proves to be a good method for fast screening PAHs.
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Increasingly erratic flow in the upper reaches of the Mara River, has directed attention to land use change as the major cause of this problem. The semi-distributed hydrological model SWAT and Landsat imagery were utilized in order to 1) map existing land use practices, 2) determine the impacts of land use change on water flux; and 3) determine the impacts of climate change scenarios on the water flux of the upper Mara River. This study found that land use change scenarios resulted in more erratic discharge while climate change scenarios had a more predictable impact on the discharge and water balance components. The model results showed the flow was more sensitive to the rainfall changes than land use changes but land use changes reduce dry season flows which is a major problem in the basin. Deforestation increased the peak flows which translated to increased sediment loading in the Mara River.
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With the flow of the Mara River becoming increasingly erratic especially in the upper reaches, attention has been directed to land use change as the major cause of this problem. The semi-distributed hydrological model Soil and Water Assessment Tool 5 (SWAT) and Landsat imagery were utilized in the upper Mara River Basin in order to 1) map existing field scale land use practices in order to determine their impact 2) determine the impacts of land use change on water flux; and 3) determine the impacts of rainfall (0%, ±10% and ±20%) and air temperature variations (0% and +5%) based on the Intergovernmental Panel on Climate Change projections on the water flux of the 10 upper Mara River. This study found that the different scenarios impacted on the water balance components differently. Land use changes resulted in a slightly more erratic discharge while rainfall and air temperature changes had a more predictable impact on the discharge and water balance components. These findings demonstrate that the model results 15 show the flow was more sensitive to the rainfall changes than land use changes. It was also shown that land use changes can reduce dry season flow which is the most important problem in the basin. The model shows also deforestation in the Mau Forest increased the peak flows which can also lead to high sediment loading in the Mara River. The effect of the land use and climate change scenarios on the sediment and 20 water quality of the river needs a thorough understanding of the sediment transport processes in addition to observed sediment and water quality data for validation of modeling results.
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Intercomparison of three new chemical ice core records from northern Greenland (covering the time span from approximately 1500 A.D. to present) with previously published records for southern and central Greenland reveals a uniform timing of anthropogenic changes in sulfate and nitrate firn concentrations over the entire ice sheet. The anthropogenic sulfate increase started around 1890, was interrupted by a transient decrease in the 1930s, and has resumed a major increase since 1950. Since the late 1970s though, a significant 30% decline in Greenland sulfate firn levels can be documented. The maximum anthropogenic increase in northern Greenland sulfate firn concentrations (up to 200-230 ppb) is 2-3 times larger than in southern and central Greenland. Nitrate records show an essentially steady increase since 1950 and, documented for the first time, a slight reduction during most recent years. Maximum nitrate firn levels of 100-130 ppb exceed the preindustrial background by 100% all over the Greenland ice sheet. Comparison with anthropogenic SO2 and NO x emission records indicates that the major increase in sulfate firn concentrations since 1950 can be attributed to Eurasian sources, while firn levels during the first half of this century appear to be dominated by North American emissions. A stronger North American source contribution is indicated over the entire 20th century in the case of nitrate. Applying a macroscopic deposition model separate time series for wet and dry deposition were derived which revealed a close correspondence of wet deposited sulfate with the timing of U.S. emissions, while the temporal evolution of Eurasian emissions is mainly reflected in the dry sulfate deposition record. During this century wet sulfate deposition increased by a factor of two while the total dry sulfate deposition flux increased by more than 500%. Wet and dry nitrate deposition both increased by 100% during the same period.
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General note: Title and date provided by Bettye Lane.
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Statins are a class of drug that inhibits cholesterol biosynthesis, and are used to treat patients with high serum cholesterol levels. They exert this function by competitively binding to the enzyme 3-hydroxy-3-methylglutaryl-CoenzymeA reductase (HMGR), which catalyses the formation of mevalonate, a rate-limiting step in cholesterol biosynthesis. In addition, statins have what are called “pleiotropic effects”, which include the reduction of inflammation, immunomodulation, and antimicrobial effects. Statins can also improve survival of patients with sepsis and pneumonia. Cystic fibrosis (CF) is the most common recessive inherited disease in the Caucasian population, which is characterised by factors including, but not limited to, excessive lung inflammation and increased susceptibility to infection. Therefore, the overall objective of this study was to examine the effects of statins on CFassociated bacterial pathogens and the host response. In this work, the prevalence of HMGR was examined in respiratory pathogens, and several CF-associated pathogens were found to possess homologues of this enzyme. HMGR homology was analysed in Staphylococcus aureus, Burkholderia cenocepacia and Streptococcus pneumoniae, and the HMGR of B. cenocepacia was found to have significant conservation to that of Pseudomonas mevalonii, which is the most widely-characterised bacterial HMGR. However, in silico analysis revealed that, unlike S. aureus and S. pneumoniae, B. cenocepacia did not possess homologues of other mevalonate pathway proteins, and that the HMGR of B. cenocepacia appeared to be involved in an alternative metabolic pathway. The effect of simvastatin was subsequently tested on the growth and virulence of S. aureus, B. cenocepacia and S. pneumoniae. Simvastatin inhibited the growth of all 3 species in a dose-dependent manner. In addition, statin treatment also attenuated biofilm formation of all 3 species, and reduced in vitro motility of S. aureus. Interestingly, simvastatin also increased the potency of the aminoglycoside antibiotic gentamicin against B. cenocepacia. The impact of statins was subsequently tested on the predominant CF-associated pathogen Pseudomonas aeruginosa, which does not possess a HMGR homologue. Mevastatin, lovastatin and simvastatin did not influence the growth of this species. However, sub-inhibitory statin concentrations reduced the swarming motility and biofilm formation of P. aeruginosa. The influence of statins was also examined on Type 3 toxin secretion, quorum sensing and chemotaxis, and no statin effect was observed on any of these phenotypes. Statins did not appear to have a characteristic effect on the P. aeruginosa transcriptome. However, a mutant library screen revealed that the effect of statins on P. aeruginosa biofilm was mediated through the PvrR regulator and the Cup fimbrial biosynthesis genes. Furthermore, proteomic analysis demonstrated that 6 proteins were reproducibly induced by simvastatin in the P. aeruginosa swarming cells. The effect of statins on the regulation of the host-P. aeruginosa immune response was also investigated. Statin treatment increased expression of the pro-inflammatory cytokines IL-8 and CCL20 in lung epithelial cells, but did not attenuate P. aeruginosa-mediated inflammatory gene induction. In fact, simvastatin and P. aeruginosa caused a synergistic effect on CCL20 expression. The expression of the transcriptional regulators KLF2 and KLF6 was also increased by statins and P. aeruginosa, with the induction of KLF6 by simvastatin proving to be a novel effect. Interestingly, both statins and P. aeruginosa were capable of inducing alternative splicing of KLF6. P. aeruginosa was found to induce KLF6 alternative splicing by way of the type 3 secreted toxin ExoS. In addition, a mechanistic role was elucidated for KLF6 in the lung, as it was determined that statin-mediated induction of this protein was responsible for the induction of the host response genes CCL20 and iNOS. Moreover, statin treatment caused a slight increase in infection-related cytotoxicity, and increased bacterial adhesion to cells. Taken together, these data demonstrate that statins can reduce the virulence of CFassociated bacterial pathogens and alter host response effectors. Furthermore, novel statin effectors were identified in both bacterial and host cells.
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This research explores the policy implications of the approval of three wind energy projects on the Oak Ridges Moraine, and their impact on the Coordinated Land Use Planning Review process. Specifically, it focuses on the involvement of First Nations and environmental non-governmental organizations (ENGOs). This research was conducted through analyzing submissions to the Coordinated Land Use Planning Review, related legislation and policy, Environmental Review Tribunal hearing documents, and interviews with key informants. This research culminates in a number of recommendations to the Coordinated Review informed by the analysis.
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People with foot problems need special healthcare: foot care. Customized insoles can provide this care. They are inserts that are placed in the shoes. They correct biomechanical and postural inaccuracies in foot. Insole production contains four phases: foot image scanning, image validation, insole design and insole manufacturing. Currently, image scanning and validation is separated in location and time, i.e. podiatrists take images and insole designers validate them at different location and at different time. A cloud-based solution, the CloudSME one-stop shop simulation platform, enables remote access to image validation and insole design service deployed and running on the Cloud. The remote access allows podiatrists validating scanned image while the patient is in their offices. The simulation platform also supports remote design of customized insoles.
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Guaranteed under the Federal Constitution of 1988, Brazilian social security covers rights relating to health, social welfare and social care. The Continuous Cash Benefit Programme (BPC) was approved as part of social care policy and is regulated under the Social Care Act (Ley Orgánica de Asistencia Social) of 1993. This benefit guarantees a minimum monthly income for persons with disabilities and for older adults. Certain requirements must be satisfied in order to obtain the assistance: medical and social assessment of disabled persons, a minimum age of 65 years for older adults, and, in both cases, the value of per capita income for the nuclear family in question, which must be lower than a quarter of the minimum wage. Regulation of the BPC has incorporated advances and setbacks in terms of legislation and implementation. In this framework, this article presents a theoretical reflection, an analysis of the legislation on the matter, and some reflections on the challenges that it poses for social workers.