11,449 research outputs found
No-arbitrage condition and existence of equilibrium with dividends
In this paper we first give an elementary proof of existence of equilibrium with dividends in an economy with possibly satiated consumers.We then introduce a no-arbitrage condition and show that it is equivalent to the existence of equilibrium with dividends.equilibrium with dividends, economy with possibly satiated consumers, no-arbitrage condition
The efficacy of topical agents in the treatment of bacterial biofilms: an in vivo sheep study and an in vitro study.
Introduction:
Recent evidence has demonstrated the presence of bacterial biofilms on the mucosa of patients with Chronic Rhinosinusitis (CRS), suggesting their role in the pathogenesis of the condition. This thesis contains two separate studies. The studies investigated novel topical therapies by using previously established in vitro and in vivo biofilm growth and detection methods. In the first study, several different proposed anti-biofilm agents were evaluated in a sheep biofilm model, each with varying degrees of immediate and short-term success against Staphylococcus aureus biofilms. A second study was conducted to determine the in vitro anti-bacterial and anti-biofilm properties of Chitosan/Dextran (CD) gel, a novel chitosan-based product with remarkable mucosal healing and haemostatic properties.
Methods:
Three alternative anti-biofilm treatments: Mupirocin, CAZS (Citric Acid Zwitterionic Acid) and Gallium Nitrate were evaluated in a prospective randomized controlled single-blinded trial using a previously established sheep biofilm model of CRS. The sheep mucosal samples were analyzed for presence of S. aureus biofilms using BacLight staining and CLSM, and the degree of biofilm involvement was determined using FISH (Fluorescence In-Situ Hybridization). The MIC/MBC values for CD gel and its constituents were determined by macro-dilution methods described by Jorgensen et al.[1]. Established in vitro biofilms grown from common CRS pathogens (ATCC strains and clinical isolates) were subjected to treatment by CD gel and its components (chitosan and dextran). A 96-well micro-titre crystal-violet staining method described by O’Toole and Kolter [2] was used to determine the anti-biofilm profile of CD gel against several bacterial strains with known biofilm-forming capacity.
Results:
Following 8 days of inoculation with S. aureus, all treatment groups in the sheep biofilm model showed a statistically significant reduction in biofilm surface coverage compared to no treatment. Importantly, sheep frontal sinuses treated with twice-daily mupirocin flushes for 5 days showed almost negligible biofilm growth after the follow-up period of 8 days (0.84% ± 1.25% surface area coverage per visual field). The overall data from the in vitro studies suggest that CD gel has marked anti-microbial activity against planktonic and biofilm-forming bacteria. It was inhibitory and bacteriocidal at sub-clinical concentrations (25mg/mL) for all bacteria tested except for E. coli. When tested against a nutrient-free environment as well as a positive growth control, bacteria were essentially unable to grow in its presence.
Conclusion:
Recalcitrant CRS is a difficult condition to manage and its pathogenesis has been closely linked to the presence of bacterial biofilms. Using a standardized biofilm sheep model of CRS, regular treatment with mupirocin flushes over a 5 day period showed an almost complete eradication of biofilms as assessed by mucosal surface coverage, with sustained effects over the 8 day period of follow-up. Equally as efficacious in the in vitro setting, CD gel demonstrated potent anti-bacterial and anti-biofilm activity against a number of pathogenic organisms suspected of being involved in acute and chronic rhinosinusitis. CD gel’s favourable haemostatic and mucosal healing profile posits it as an ideal post-ESS packing material.
These two topical agents therefore hold promise as effective treatment options in the management of CRS.Thesis (M.S.) -- University of Adelaide, School of Medicine, 201
R-Continuity with Applications to Convergence Analysis of Tikhonov Regularization and DC Programming
In the paper, we study the convergence analysis of Tikhonov regularization in
finding a zero of a maximal monotone operator using the notion of R-continuity.
Applications to convex minimization and DC programming are provided
Determinant of the Factors Affecting Foreign Direct Investment (FDI) Flow to Thanh Hoa Province in Vietnam
AbstractThis paper attempts to identify the main factors that help with the attraction of foreign direct investment capital in Thanh Hoa province in Vietnam. In this study, with forty-one questionnaires have been sent to foreign companies in many region for observation. The survey results show that there are some factors that have been evaluated as much more important such as Availability of resources factors, Infrastructure factors and financial factors; while, others are considered to be relatively less important in the current context of Thanh Hoa province in Vietnam such as social and cultural factors
Water yield estimation and sedimentation control in two Volta sub-basins: tools towards integrated water resources management
Small reservoirs form a major source of water supply in the Volta basin. However, sedimentation of reservoirs poses serious threats to overall water yield and storage, consequently impacting community water supplies and livelihoods. This study will assess basin-level water yields and sediment inflow deposited in reservoirs in two Volta sub-basins using the WEAP and SWAT models in combination with spatial analysis techniques. The WEAP Model will assess water allocations while the SWAT model will compute water balance, runoff and sediment yields. Ancillary measured sediment yield data will be used in combination with terrain-based distributed models in a GIS to identify and predict major areas of erosion in the two study sites. Social and biophysical dynamics will be concomittantly assessed through a multi-agent modeling framework (ComMod). To this end, the WEAP and SWAT models will be linked to the computer simulation tool of the ComMod platform. This will allow for assessing the consequences of local practices -and possibly proposed intervention- in terms of erosion (see figure). The results and the approach can be used as decision-support tools to identify practical IWRM interventions that reduce erosion e.g. vegetation strip-ways. It is anticipated that this will result in improved water resources management and reduce impacts of drought spell shocks on the affected communities and could be replicated elsewhere in the Volta basin. (Texte intégral
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