Two-step low-temperature oxidation for thermal stability analysis of a combustible sphere

Thermal stability of reactive materials in a stockpile which spontaneously ignites is investigated in this article. The stockpile is modeled in a spherical domain assumed to be of a constant thermal conductivity. The energy equation is modified to a partial differential equation that is most suitable to analyze thermal stability of the combusting material. This is carried out by looking at the behavior of the temperature as selected parameters embedded in the governing equation are varied. The governing equation is solved numerically by using the Finite Difference Method (FDM). The results are given graphically and discussed appropriately to provide an understanding of the complicated combustion process. Keywords: Thermal conductivity, Low-temperature oxidation, Spontaneous ignition, Sphere, Finite Difference Metho

Exploring the Influence of Daily Climate Variables on Malaria Transmission and Abundance of Anopheles arabiensis over Nkomazi Local Municipality, Mpumalanga Province, South Africa

The recent resurgence of malaria incidence across epidemic regions in South Africa has been linked to climatic and environmental factors. An in-depth investigation of the impact of climate variability and mosquito abundance on malaria parasite incidence may therefore offer useful insight towards the control of this life-threatening disease. In this study, we investigate the influence of climatic factors on malaria transmission over Nkomazi Municipality. The variability and interconnectedness between the variables were analyzed using wavelet coherence analysis. Time-series analyses revealed that malaria cases significantly declined after the outbreak in early 2000, but with a slight increase from 2015. Furthermore, the wavelet coherence and time-lagged correlation analyses identified rainfall and abundance of Anopheles arabiensis as the major variables responsible for malaria transmission over the study region. The analysis further highlights a high malaria intensity with the variables from 1998–2002, 2004–2006, and 2010–2013 and a noticeable periodicity value of 256–512 days. Also, malaria transmission shows a time lag between one month and three months with respect to mosquito abundance and the different climatic variables. The findings from this study offer a better understanding of the importance of climatic factors on the transmission of malaria. The study further highlights the significant roles of An. arabiensis on malaria occurrence over Nkomazi. Implementing the mosquito model to predict mosquito abundance could provide more insight into malaria elimination or control in Africa

Exploring the Influence of Daily Climate Variables on Malaria Transmission and Abundance of Anopheles arabiensis over Nkomazi Local Municipality, Mpumalanga Province, South Africa.

The recent resurgence of malaria incidence across epidemic regions in South Africa has been linked to climatic and environmental factors. An in-depth investigation of the impact of climate variability and mosquito abundance on malaria parasite incidence may therefore offer useful insight towards the control of this life-threatening disease. In this study, we investigate the influence of climatic factors on malaria transmission over Nkomazi Municipality. The variability and interconnectedness between the variables were analyzed using wavelet coherence analysis. Time-series analyses revealed that malaria cases significantly declined after the outbreak in early 2000, but with a slight increase from 2015. Furthermore, the wavelet coherence and time-lagged correlation analyses identified rainfall and abundance of Anopheles arabiensis as the major variables responsible for malaria transmission over the study region. The analysis further highlights a high malaria intensity with the variables from 1998-2002, 2004-2006, and 2010-2013 and a noticeable periodicity value of 256-512 days. Also, malaria transmission shows a time lag between one month and three months with respect to mosquito abundance and the different climatic variables. The findings from this study offer a better understanding of the importance of climatic factors on the transmission of malaria. The study further highlights the significant roles of An. arabiensis on malaria occurrence over Nkomazi. Implementing the mosquito model to predict mosquito abundance could provide more insight into malaria elimination or control in Africa

Investigating the resurgence of malaria prevalence in South Africa between 2015 and 2018 : a scoping review

BACKGROUND : Malaria remains a serious concern in most African countries, causing nearly one million deaths globally every year. This review aims to examine the extent and nature of the resurgence of malaria transmission in South Africa. METHODS : Using the Arksey and O'Malley framework, this scoping review includes articles published between the years 2015 and 2018 on the resurgence of malaria occurrence in South Africa. Articles were searched between October 2018 to January 2019 using the following electronic databases: CINAHL, Pubmed, Science Direct and SCOPUS. Grey literature from Google Scholar was also hand searched. Key search terms and subject headings such as climate variables, climate changes, climatic factors, malaria resurgence, malaria reoccurrence and malaria increase over epidemic regions in South Africa were used to identify relevant articles. Three independent reviewers performed the selection and characterization of articles, and the data collected were synthesized qualitatively. RESULTS : A total number of 534 studies were identified. Among these, 24 studies met the inclusion criteria. The results were grouped by factors (four main themes) that influenced the malaria resurgence: Climatic, Epidemiological, Socio-economic, and Environmental factors. Climatic factors were found to be the major factor responsible for the resurgence of malaria, as more than 55% of the selected articles were climate-focused. This was followed by epidemiological, socio-economic and environmental factors, in that order. Grey literature from Google Scholar yielded no results. CONCLUSION : This study shows that malaria transmission in South Africa is more associated with climate. Climate-based malaria models could be used as early warning systems for malaria over the epidemic regions in South Africa. Since epidemiological factors also play significant roles in malaria transmission, regular and unrelaxed use of Indoor Residual Spraying (IRS) should be encouraged in these regions. Individuals should also be educated on the importance and the usefulness of these deliveries. While some studies have indicated that the vectors have developed resistance to insecticides, continuous research on developing new insecticides that could alter the resistance are encouraged. Furthermore, all efforts to eradicate malaria in South Africa must also target malaria-endemic neighbouring countries.The University of Pretoria Institute for Sustainable Malaria Control (UP ISMC) and Malaria Research Control (MRC)https://benthamopen.com/TOPHJ/home/am2021School of Health Systems and Public Health (SHSPH