Study of Infectious Diseases by Mathematical Models: Predictions and Controls

The aim of this thesis is to understand the spread, persistence and prevention mechanisms of infectious diseases by mathematical models. Microorganisms that rapidly evolve pose a constant threat to public health. Proper understanding of the transmission machinery of these existing and new pathogens may facilitate devising prevention tools. Prevention tools against transmissions, including vaccines and drugs, are evolving at a similar pace. Efficient implementation of these new tools is a fundamental issue of public health. We primarily focus on this issue and explore some theoretical frameworks. Pre-exposure prophylaxis (PrEP) is considered one of the promising interventions against HIV infection as experiments on various groups and sites have reported its significant effectiveness. This study evaluates the effectiveness of Tenofovir gel, one of the widely used PrEPs for women, through a mathematical model. Our model has excellent agreement with the experimental data on the use of Tenofovir gel as a PrEP in South African women. Using our model, we estimate both male-to-female and female-to-male transmission rates with and without Tenofovir gel protection. Through these estimates, we demonstrate that the use of Tenofovir gel as a PrEP can significantly reduce the reproduction numbers, new infections, and HIV prevalence in South Africa. Our results further show that the effectiveness of Tenofovir gel largely depends on the level of adherence to the gel and the proportion of women under gel coverage. Even though Tenofovir gel alone may not be able to eradicate the disease, as indicated by our estimates of the reproduction numbers, together with other interventions, such as condom use, it can serve as a strong weapon to fight against HIV epidemics. Another promising drug-oriented intervention against HIV infection is antiretroviral treatment (ART). We study some crucial aspects of this intervention on the HIV epidemic. ART has the potential to reduce mortality and disease progression among HIV infected individuals. It can reduce the viral load of the infected individual to an undetectable level and help prevent new infections. Whether the treatment should begin early or be delayed is still under debate. This study considers the impact of early versus delayed ART on the HIV epidemic and demonstrates the optimum timing of ART initiation. Our results highlight the long-term consequences of early treatment. Finally, we investigate the consequences of vaccine implementation strategies for infectious diseases. Vaccines are said to be the intervention with the most potential against many infectious diseases. However, their success relies on proper and strategic management and distribution. In an infectious disease, the degree of infection may vary widely among those individuals. Reports show that individuals belonging to certain groups possess considerably higher risk for infection. Integrating this phenomenon into vaccination strategies, the host is categorized into different groups to measure the outcome of the vaccination. A mathematical model is proposed and analyzed to evaluate this measure. Our results suggest that vaccinating a group with a certain priority may lead to effective elimination of the disease

マウス瞬目反射逐次型特徴陽性弁別課題におけるムスカリン性アセチルコリン受容体と海馬シータ振動の関与

富山大学・富生命博甲第83号・MD. ASHRAFUR RAHMAN・2016/03/23富山大学201

Framework to Facilitate Urban Regeneration in the Middle Suburbs of Car-dependent Cities

Car-dependent cities with large urban footprints suffer from a lack of planning mechanisms to regenerate their middle-suburbs. Among the principle methods, subdivisions have been found to be sub-optimal solutions while the impacts of transport infrastructure in regenerating middle-suburbs are yet to be explored. Using multi-criteria-evaluation tools, this research examines the socio-technical parameters of middle-suburbs to assess redevelopment potentials of any proposed transit corridor. Perth, Western Australia, is investigated in this study as a typical case

Performance of Data Transmission for mobile applications

Mobile applications have empowered and extended the usability of mobile devices far beyond merely supporting voice communication. The development of mobile applications, however, must deal with a variety of unique problems: limited working memory, limited storage, limited processing power, and small screen size. Mobile applications which rely on remote data sources and databases are particularly challenging given the need to transmit data through wireless media and often involve complex business logic. Our main goal is to improve the performance of mobile applications which rely on remote data sources and databases. In this research work, we compare different data transmission optimization techniques, different middleware approaches and identify combinations of approaches for improving performance of data transmission over wireless network. The results of this research provide useful guidelines for the development of mobile applications needing to connect to remote databases or data sources

Document Layout Analysis on BaDLAD Dataset: A Comprehensive MViTv2 Based Approach

In the rapidly evolving digital era, the analysis of document layouts plays a pivotal role in automated information extraction and interpretation. In our work, we have trained MViTv2 transformer model architecture with cascaded mask R-CNN on BaDLAD dataset to extract text box, paragraphs, images and tables from a document. After training on 20365 document images for 36 epochs in a 3 phase cycle, we achieved a training loss of 0.2125 and a mask loss of 0.19. Our work extends beyond training, delving into the exploration of potential enhancement avenues. We investigate the impact of rotation and flip augmentation, the effectiveness of slicing input images pre-inference, the implications of varying the resolution of the transformer backbone, and the potential of employing a dual-pass inference to uncover missed text-boxes. Through these explorations, we observe a spectrum of outcomes, where some modifications result in tangible performance improvements, while others offer unique insights for future endeavors

A Bi-Objective Approach to Evaluate Highway Routing and Regulatory Strategies for Hazardous Materials Transportation

Hazardous materials (hazmat) transportation is of concern to policymakers because of the serious safety, health, and environmental risks associated with the release of hazmat. One effective approach to minimize risks associated with hazmat transport is the prohibition of hazmat transportation on higher risk links that either pose safety hazards or increased exposure by traversing densely populated areas. Because of high risk, there are multiple stakeholders involved in hazmat transportation. While shippers and carriers are directly involved in making routing decisions, regulatory agencies influence this decision by imposing routing restrictions. In this paper, we apply a bi-objective shortest path problem to evaluate routing and regulation plans for hazmat transportation. We characterize the cost objective as the shortest path between an origin and a destination. The risk objective is to minimize the risk of exposure by restricting the link with the highest risk on the best available path from an origin to a destination. We formulate the bi-objective model and apply it to a test network. Solutions consider multiple origin-destination pairs and present a non-dominated frontier to establish routing and regulatory strategies for hazmat transportation

Shoot and Root Growth and Yield of Eggplant Cultivars as Affected by Wilt Disease

An experiment was conducted in the Field of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh to screen out the resistant cultivars of eggplant against wilt disease. Eight cultivars viz. Nayantara, Singhnath, Dhundul, Kazla, Marich Begun Luffa, Kata Begun and Uttara were used as treatments. The highest shoot height was recorded in the cultivar Kata Begun and the lowest shoot height was recorded in the cultivar Singhnath. The highest gall number was recorded in the cultivar Luffa and the lowest gall number was recorded in the cultivar Kata Begun. The highest yield per hectare (29.84 t/ha) was recorded in the cultivar Nayantara and the lowest yield (10.50 t/ha) was recorded in the cultivar Dhundhul. Among the cultivars Kata Begun graded as resistant for both Bacterial, Fungal and Nemic wilt

Advancing Risk Assessment: Mechanistic Dose-response Modelling of Listeria monocytogenes Infection in Human Populations

Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited. The utility of characterizing the effects of strain variation and individual/subgroup susceptibility on dose-response outcomes has motivated the search for new approaches beyond the popular use of the exponential dose-response model for listeriosis. While descriptive models can account for such variation, they have limited power to extrapolate beyond the details of particular outbreaks. By contrast, this study exhibits dose-response relationships from a mechanistic basis, quantifying key biological factors involved in pathogen-host dynamics. An efficient computational algorithm and geometric interpretation of the infection pathway are developed to connect dose-response relationships with the underlying bistable dynamics of the model. Relying on in vitro experiments as well as outbreak data, we estimate plausible parameters for the human context. Despite the presence of uncertainty in such parameters, sensitivity analysis reveals that the host response is most influenced by the pathogen-immune system interaction. In particular, we show how variation in this interaction across a subgroup of the population dictates the shape of dose-response curves. Finally, in terms of future experimentation, our model results provide guidelines and highlight vital aspects of the interplay between immune cells and particular strains of Listeria monocytogenes that should be examined

Screening of Different Eggplant Cultivars against Wilt Disease Caused by Fungi, Bacteria and Nematodes

An experiment was conducted in the Field of Sher-e-Bangla Agricultural University, Dhaka to screen out the resistant cultivars of eggplant against wilt disease. Eight cultivars viz. Nayantara, Singhnath, Dhundul, Kazla, Marich Begun Luffa, Kata Begun and Uttara were used as treatments. At 55 days after transplanting (DAT) the cultivar Luffa exhibit the highest bacterial wilt incidence (80%) and the lowest wilt incidence was recorded in the cultivar Kata Begun (30%). At 90 DAT the highest Fusarium and Nemic wilt incidence was recorded in the cultivar Luffa and the lowest wilt incidences were recorded in the cultivar Kata Begun. The highest shoot height was recorded in the cultivar Kata Begun and the lowest shoot height was recorded in the cultivar Singhnath. The highest gall number was recorded in the cultivar Luffa and the lowest gall number was recorded in the cultivar Kata Begun. The highest yield per hectare (29.84 t/ha) was recorded in the cultivar Nayantara and the lowest yield (10.50 t/ha) was recorded in the cultivar Dhundhul. Among the cultivars Kata Begun graded as resistant for both Bacterial, Fungal and Nemic wilt.ÂÂ