The antimicrobial activity and phytochemistry of african wormwood ( artemisia )

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Science In Medicine ( Pharmaceutical Affairs )Artemisia afra Jacq. wild also known as African wormwood, " umhlonyane" ( Xhosa and Zulu ) "lengana" ( Sotho And Tswana ) and "wildeals" ( Afrikaans 0 is an aromatic shrub belonging to the Asteraceace. It is widespread in South Africa extending from the mountainous regions of South Western cape, along the eastern coast to the Northern Province ( van Wyk et. al;1997 ) Due to the popular use of A. afra. The aerial part of sixteen samples from four natural populations were hydrodistilled and the essential oil analysed by GC_MS and tested for antimicrobial activity on anumber of bacteria and fungi.IT201

Transient boiler heat exchanger thermal behaviour analysis

Includes bibliographical references.Coal fired power plants that were built in the past four decades are aging. The main aging mechanisms are creep and thermal fatigue. Creep results from the high temperatures at which the components operate. Thermal fatigue is due to thermal stresses and these stresses result from temperature gradients within the material. Cycling of these thermal stresses accelerate the creep in a process called creep- fatigue aging. The boiler and its final heat exchangers and headers are the main components that are affected by these mechanisms. The aging of these components results in high maintenance costs, reduction of the plant reliability and availability, and contribute to increased safety risks for the plant and personnel. Therefore, there is a need to understand the steady state and dynamic behaviour of the components of these plants in order to predict the stresses that the material experience. This report discusses an investigation to the possibility of modelling the thermal dynamic behaviour of typical boiler heat exchanger components which have to withstand the highest temperature of a Pulverised Fuel Rankine cycle power plant. Thus, illuminating the issues that need to be addressed in modelling such heat exchangers. Modelling approaches of heat exchangers are systematically presented, starting with the use of exact analytical solutions. This is followed by the application of finite volume numerical method. Finishing off with the use of the Flownex software. The exact analytical solutions are used to characterise the transient temperature distribution in solid materials with simplified heat transfer, highlighting the dependence of the solutions on the Fourier number and Biot number. These solutions are further used to calculate thermal stresses generated in the material, illustrating the relationship between thermal stresses and temperature gradients. Furthermore, a finite volume solution is applied to modelling an infinitely long tube. I t is illustrated that for transient conduction heat transfer problems, the solution depends on both physical space discretisation and time- wise discretisation. The numerical solution is verified against the exact analytical solution. Finally, the Flownex software is used to illustrate the issues that need to be addressed when modelling the transient behaviour of a heat exchanger . For this purpose only the average area discretisation scheme is used since it allows for any generic solid structure to be modelled, provided that the appropriate level of discretization is applied. The Flownex modelling starts by modelling transient conduction heat transfer within an infinitely long tube. The Flownex solution is verified against the finite volume numerical solution. The Flownex solution depends on thickness discretisation, especially for thick cylindrical components. Finite tubes are also modelled on Flownex including axial discretisation and layout simplification of the tubes. Flownex is also used to model a heat exchanger bundle using two methods; a tube by tube method and a method that involves the combination of all ii the tubes into one tube. The product of the thermal resistance and the capacitance of the system governs the transient simulations for both methods

A STUDY OF CONSUMERS AT A SMALL FARMERS' MARKET IN MAINE: RESULTS FROM A 1995 SURVEY

This study was based on a survey of customers who shopped at a small farmers' market during the summer/fall market season of 1995. Information from a survey completed by 239 shoppers was used to develop a profile of the primary consumer group, defined as those who shop regularly at the market and spend the most per visit. Comparisons between survey data and census data for the local population showed that primary shoppers at the market had higher education, higher annual household income, tended to be slightly older, and were more likely to be employed women. For the most part, the respondents were loyal, weekly shoppers who patronized the market because of the high quality of the products. Most reported that they were willing to pay more for produce at the farmers' market.Consumer/Household Economics,

Factors Influencing Data Breaches in Healthcare Organizations: A Comprehensive Analysis

Data breaches pose significant risks to patient privacy and security, especially in healthcare organizations. Despite the valuable insights provided by prior studies, a notable gap exists regarding the examination of technological and organizational factors that contribute to breaches. This study employs the Technology, Organization, and Environment (TOE) framework to provide insights into how data security in healthcare organizations can be enhanced. The TOE framework enables a thorough examination of the relationships between technical infrastructure, organizational variables, and the external environment, offering a holistic view of potential data security vulnerabilities. Within this framework, this study specifically explores the interplay between technological infrastructure, human resource management, and security protocols, with the goal of better understanding the variables that contribute to data breaches in the healthcare industry. The preliminary findings indicate a notable trend wherein breached healthcare organizations exhibit a higher employment of full-time equivalent (FTE) programmers and network administrators, suggesting a potential vulnerability stemming from system complexity or heightened susceptibility points. Yet, distinctions in other staffing categories, overall FTEs, and hospital size were not significant. When observing security software, these compromised organizations reflected reduced usage of comprehensive security tools like antivirus, data loss prevention, encryption, and user authentication mechanisms. This emphasizes the centrality of a fortified technological infrastructure in alignment with the TOE framework. Interestingly, a pronounced reliance on firewall software was identified among breached institutions, potentially indicating an overemphasis on this singular defense mechanism. The research also found an absence of a marked difference in the adoption of biometric technologies between breached and secure organizations. This revelation underscores that biometric adoption in isolation may not drastically alter breach likelihood, accentuating the importance of other TOE dimensions such as robust user training and regulatory compliance. Furthermore, apart from a decreased usage of Thin Clients, the overall computer system configuration did not present significant variations, suggesting that the mere deployment type or volume of systems may not directly correlate with breach probabilities. In line with this, breached organizations displayed reduced employment of diverse server types, aligning with the TOE framework\u27s technological dimension, which proposes that server diversity may augment system resilience. Nonetheless, it\u27s imperative to recognize that the type of server alone isn\u27t the lone breach determinant, reiterating the holistic necessity of considering all facets of the TOE framework, inclusive of encompassing security protocols and external determinants

UNDERSTANDING THE COST ASSOCIATED WITH DATA SECURITY BREACHES

To estimate the cost of a data breach to the inflicted firm, this study examines the relationship between a breach incident and changes in the inflicted firm’s profitability, perceived risk, and the inflicted firms’ information environment transparency. Profitability is measured as reported earnings and analysts’ earnings forecasts. Perceived risk is measured as reported stock return volatility and dispersion among analysts’ forecasts. Although a number of studies have investigated the stock market reaction surrounding the disclosure of a breach incident to quantify the cost associated with breaches, we argue that there exists information uncertainty and deficiency in the disclosure of the breach incident and stock market reaction surrounding a security breach announcement date may not be the best measure for the cost of security breaches. And research using other complementary measures is warranted. Our preliminary finding suggests that data breaches negatively impact firm profitability, perceived risk and information transparency. Nevertheless, the damage of a breach most likely stems from direct costs such as compensation and litigation costs rather than indirect costs such as tarnished reputation and a decrease in market share and sales. More sophisticated analysts are also found to add value in estimating the real cost of a security breach

No. 17: The State of Food Insecurity in Gaborone, Botswana

The results of AFSUN’s study of the food security situation of the poor in Gaborone show that not everyone is benefitting from Botswana’s strong and growing economy and that many of the urban poor experience extremely high levels of food insecurity. The study, which formed part of AFSUN’s baseline survey of 11 Southern African cities, collected data on a broad range of issues that affect household food insecurity and found that four out of five households in the surveyed areas in Gaborone reported severe or moderate food insecurity. Only 18% were either food secure or mildly food insecure. Income level is a particularly important determinant of food insecurity as most households access food from the marketplace rather than grow their own. The impacts of chronic food insecurity on Gaborone’s population are likely to be considerable unless this problem is urgently addressed. The problem is in some sense invisible because there appears to be no shortage of food in the shops and on the streets of this booming city. The challenge is not one of food supply but food accessibility and food quality. Given that Botswana is one of the most rapidly urbanizing and most urbanized countries in Africa, its example has wider importance for the general study of urban food security on the continent

A Conceptual Framework for Understanding Trust Building and Maintenance in Virtual Organizations

The issue of trust development in traditional organizations has been widely discussed in the academic literature for several years. Recently, scholars have also studied trust development in temporary groups and have noted some fundamental differences between the manner in which trust develops in traditional organizations and the manner in which it develops in temporary groups. Virtual organizations are a new type of organization characterized by traits of both traditional organizations and temporary groups. This paper integrates the literature on trust in virtual organizations and the perspectives of trust development in both traditional organizations and temporary groups to develop a process-based framework which facilitates the understanding of trust development in the virtual organization setting

Differential Market Reaction to Data Security Breaches: A Screening Perspective

This paper aims to identify breach- and firm-level characteristics that may account for the heterogenous stock market reaction to data breaches. Drawing upon the screening theory, this paper examines the possibility of three breach characteristics (breach severity, breach locus and breach controllability) and two firm attributes (CEO stock ownership, and corporate social responsibility (CSR) performance) serving as information screens to influence stock market reaction to a data breach incident. Using an archival dataset compiled from multiple sources, we examine 607 data breaches from 2004 to 2018 and find that the stock market reacts more negatively if a breach is more severe (i.e., involving more data records and financially sensitive consumer data), controllable (i.e., could have been prevented), and if the breached firm has weak corporate governance, as indicated by low CEO stock ownership. Furthermore, CSR provides an “insurance-like” protection by attenuating the negative effects of breach severity, breach controllability, and poor corporate governance on firm value. Findings of this research highlight the relevance of screening theory as a theoretical lens for examining the contextual dependence of stock market reaction to data breaches on key breach- and firm-level characteristics