Preventive therapy for tuberculosis in HIV infected individuals

The increased risk of developing tuberculosis (TB) among those infected with HIV has prompted a need to reconsider the institution of preventive therapy/chemoprophylaxis with one or more antituberculosis drugs. Prior to the initiation of preventive therapy for tuberculosis, it is essential to rule out active TB. The target population for chemoprophylaxis among HIV seropositives includes all Mantoux (PPD) positive individuals who do not have active tuberculosis and could include all PPD negative individuals living in high prevalence region for TB. The optimal duration of preventive therapy with single drug isoniazid, daily or twice weekly, should be greater than six months to provide the maximum degree of protection against tuberculosis. The effectiveness of preventive therapy should be evaluated at regular intervals by monitoring patients for drug adherence, drug toxicity and for the development of tuberculosis. Though the impact of preventive therapy on an individual basis may be rather small, widespread implementation would have substantial impact on morbidity due to tuberculosis and some impact on mortality. Till the vast majority of HIV positive individuals in the world can access antiretroviral therapy, preventive therapy for tuberculosis should be offered at voluntary counselling and testing centres, as part of a package of care that includes prophylaxis and treatment of opportunistic infections, nutritional support and counselling

Temperature Dependent Neutron Scattering Sections for Polyethylene

This note presents neutron scattering cross sections for polyethylene at 296 K, 77 K and 4 K derived from a new scattering kernel for neutron scattering off of hydrogen in polyethylene. The kernel was developed in ENDF-6 format as a set of S(alpha,beta) tables using the LEAPR module of the NJOY94 code package. The polyethylene density of states (from 0 to sub eV) adopted to derive the new kernel is presented. We compare our calculated room temperature total scattering cross sections and double differential cross sections at 232 meV at various angles with the available experimental data (at room temperature), and then extrapolate the calculations to lower temperatures (77K and 4K). The new temperature dependent scattering kernel gives a good quantitative fit to the available room temperature data and has a temperature dependence that is qualitatively consistent with thermodynamics.Comment: 6 page

Agent-based engineering drawing analysis

technical reportInterpretation of paper drawings has received a good deal of attention over the last decade. Related areas such as direct interpretation of human drawings (HCI), search and indexing of graphics databases, and knowledge representation in the domain of graphics and drawing understanding have also seen advances.. One of the most interesting applications in this domain is the analysis of semantics in engineering drawings. Although several sophisticated automatic systems have been developed, for example, the CELESSTIN system in France, there are still significant problems in their application: (1) they are linear and do not allow backtracking solutions, (2) they are typically flat rulebased systems with many rules, and (3) the knowledge models are embedded directly in the rules and are unavailable in a higher-level form. We still need a more automatic, selfcontained, less complex and robust system involving minimal human intervention. The use of autonomous agents in the field of image analysis is just starting. Our thesis is that a set of nondeterministic agents provides the necessary methodology to address the shortcomings of previous systems. We explore the organization, communication and high-level knowledge representation of a set of agents designed to perform engineering drawing analysis. This permits the exploration of interesting parts of the search space, especially when combined with good pruning and focus mechanisms

RECENT APPROACHES INVOLVED IN COLONIC DRUG TARGETING FOR THE TREATMENT OF INFLAMMATORY BOWEL DISEASE: A REVIEW

The objective of the review is to present the contemporary approaches involved in colonic drug targeting for the therapy of inflammatory bowel disease (IBD). The adverse reactions and side-effects of the conventional drug delivery systems are largely on account of the systemic absorption of the drugs from the small intestine. Moreover, in current drug delivery systems, the drug has to be frequently administered and also in larger doses which greatly reduces patient compliance. Various approaches which are being described here mainly target the colonic region specifically for improved therapy of IBD, by increasing localization and accessibility of the drug to the target site. Also, these approaches will result in the reduction of dose and minimization of adverse effects combined with the use of conventional drug delivery systems

Large Eddy Simulation of Bluff Body Stabilised Premixed Flames Using Flamelets

Large Eddy Simulations of an unconfined turbulent lean practical flame stabilised behind a bluff body burner are computed using structured and unstructured numerical solvers. Unstrained flamelets are used as the sub-grid scale combustion closure using constant and dynamic formulations to model the flame curvature parameter βc. The model uses a presumed probability density function to calculate the filtered reaction rate. The aim of this study is to determine the numerical set-up that provides the most reliable results for the flame that is furthest from blow-off conditions (A1). This work will lead to modelling the flame closest to blow-off (A4) and the flame at blow-off conditions, since these flames are highly unstable. Comparisons will be drawn with experimental data obtained using PIV, OH chemiluminescence and OH-PLIF techniques.EPSRC DTP studentship (RG80792

Large Eddy Simulation of a Bluff Body Stabilised Premixed Flame Using Flamelets

Large Eddy Simulations of an unconfined turbulent lean premixed flame, which is stabilised behind a bluff body, are conducted using unstrained flamelets as the sub-grid scale combustion closure. The statistics from the simulations are compared with the corresponding data obtained from the experiment and it is demonstrated that the experimental observations are well captured. The relative positioning of the shear layers and the flame brush are analysed to understand the radial variations of the turbulent kinetic energy at various streamwise locations. These results are also compared to confined bluff body stabilised flames, to shed light on the relative role of incoming and shear driven turbulence on the behaviour of the flame brush and the turbulent kinetic energy variation across it.EPSRC DTP studentship (RG80792

Modelling Heat Loss Effects in the LES of a Lean Swirl-Stabilised Flame Close to Blow-Off

The flame in a model gas turbine combustor close to blow-off is studied using large eddy simulation with the objective of investigating the sensitivity of including different heat loss effects within the modelling. A presumed joint probability density function approach based on the mixture fraction and progress variable with unstrained flamelets is used. The normalised enthalpy is included in the probability density function to account for heat loss within the flame. Two simulations are presented with fixed temperature boundary conditions and use adiabatic and non-adiabatic formulations of the combustion model. The results are compared against the previous fully adiabatic case and experimental data. The statistics for the simulations are similar to the results obtained from the fully adiabatic case. Improved statistics are obtained for the temperature in the near-wall regions. The non-adiabatic flamelet case shows the average reaction rate values at the flame root case are approximately 50% smaller in comparison to the adiabatic flamelet cases. This causes the lift-off height to be overestimated. Further investigation will be undertaken with the non-adiabatic flamelet case, as the flame is observed to be highly unstable.EPSRC DTP studentship (RG80792