In less than two decades, African-American, female, leading-edge baby boomers (AAFLEBBs) will join the retirement population. AAFLEBBs are members of the largest generation in the history of the United States. This generation's economic well being has been threatened by high unemployment rates, factory closings and downsizings, eroding purchasing power, lack of financial management skills, and fluctuating income. There is a growing concern that boomers will not do well financially in retirement. The purpose of this study is to better understand the retirement planning process of eight AAFLEBBs. Also, this study focuses on identifying areas where additional research may be needed regarding retirement planning. This study utilized a qualitative method known as the long interview. Seven factors were identified that affected the retirement planning process of the eight African-American females studied. These factors were: the uncertain social security system, their children, job changes, parents' retirement, the fluctuating economy, day-to-day survival, and career development. Three categories were identified for additional research: retirement planning of baby boomers, methods for acquiring retirement information, and specific concerns of African-American females. One main conclusion resulted from the findings: the majority of the AAFLEBBs interviewed were giving little attention to retirement planning. Further research should be conducted on African-American females in their own context. Researchers should investigate retirement planning and how people can best prepare themselves for this time of their lives. Gerontologists could explore African-American females’ perceptions of aging and what they want to happen in their senior lives. Extension specialists, adult educators, financial planners, and other family economics and management specialists should develop information to help various groups understand the importance of preparing and planning at early ages for their eventual retirement. / Ph. D.

Most individuals spend more than half their lives as single due to divorce, widowhood, and remaining single (Simpson, 2016). Singlehood, in general, has meant not being in a heterosexual relationship. Historically, lesbian women have been considered single because their relationships were not legally recognized. Single women and lesbian women have had more choices to live outside heterosexual marriage, financially and with social acceptability, in the later portion of the 20th century and in the early 21st century than previously. Single sexual minority women of the baby boom came of age during this time and are beginning to plan for and enter into old age. This study used qualitative methods to study how single sexual minority women of the baby boom cohort defined family and planned for their later years. Women from the baby boom cohort who are currently single and identify as a sexual minority were connected to their family of origin and extended families in their youth, focused on romantic relationships during adulthood, and currently identify their family as biological and chosen family. The women had formal and informal plans for their future as they continue to age. Limitations, future directions, and implications are also discussed. / Ph. D.

La présente étude vise à comprendre le comportement chimico-hydro-mécanique des argiles raides à travers deux formations géologiques, l'argile de Boom et les argiles yprésiennes, qui sont censées être des formations hôtes potentielles pour le stockage de déchets radioactifs en Belgique. Le comportement volumique a été étudié tant à l'état intact qu'à l'état reconstitué, et sous différentes conditions : K0 et isotrope, sous des boucles de chargement - déchargement. Les résultats obtenus montrent que le comportement volumique de ces argiles est gouverné par la compétition entre l'effet physico-chimique et l'effet mécanique, caractérisée par une contrainte seuil qui correspond à la contrainte de gonflement en termes de changements de structure. Une loi de comportement volumique a été ainsi développée afin de décrire cet aspect. La perméabilité a été déterminée, comparée avec les résultats dans la littérature et corrélée avec les paramètres comme l'indice des vides. La variation de la perméabilité avec la profondeur ont mis en évidence le rôle déterminant des macro-pores dans le transfert des fluides. Le comportement volumique et la perméabilité des argiles de Boom et yprésiennes intactes sont aussi influencés par la variation de la composition chimique de l'eau de pore, qui modifie la double couche diffuse et favorise l'agrégation des particules argileuses. Les caractéristiques élastiques, la surface de charge et l'enveloppe de rupture ont été identifiées pour le comportement déviatorique des argiles de Boom et yprésiennes. Un modèle élasto-plastique conceptuel a été développé permettant de tenir compte des effets du gonflement et de la compétition entre l'effet mécanique et l'effet physico-chimique

A Report on Research Study presented to the Department of Social Work School of Human and Community Development Faculty of Humanities University of the Witwatersrand in partial fulfilment of the requirements for the degree Master of Arts in Occupational Social Work, March 2017 / The multifaceted workplace, encompassing different generations, has been seen to have its benefits and potential factors leading to conflict (Burke, 2004). Differences existing within generations often influence the organizational success, staff performance, satisfaction, creativity, group cohesion and reputation, resulting in satisfactory or unsatisfactory relations being established (Baptiste, 2009; Saba, 2013; Salahuddin, 2010). Intergenerational differences provide additional insight into work life forces impinging on human beings within the workplace, which ultimately influences the success of the organization (Gratton, 2011; Salahuddin, 2010). As such, this study will provide additional insight into how generational differences impact on employee relationships with co-workers, on individual performance, and engagement in the workplace. The qualitative research approach was used to elicit live experiences of participants, and the narrative study design applied to, efficiently allowed participants to share their story. Using interview schedules, interviews were conducted with sixteen participants selected through a nonprobability purposive sampling strategy. Semi-structured interviews were conducted following obtainment of consent from the participants, and interviews were recorded and transcribed verbatim. Data was analysed using thematic analysis whereby data was divided into themes and subthemes, interweaving these within existing literature. The study anticipated that the changing workforce influences diverse generations differently, and this has an influence on the relations established and the manner in which they respond to the changes, and in so doing meets the organizational needs. The study found that similarities exist amongst generational groups which include: access to opportunities, performance and workforce needs. The findings also show that workplace challenges exist, however, and through the use of survival strategies employees can cope when presented with challenges. The study has provided insight on how occupational social workers can develop organizational strategies and interventions, which seek to acknowledge and embrace diversity amongst employees, in order to successfully manage and work effectively with a multigenerational workforce. / XL2018

Le travail de thèse a pour but d'étudier le comportement thermo-hydro-mécanique de l'argile de Boom, choisie comme matériau hôte pour le stockage des déchets radioactifs à Mol, Belgique. En premier lieu, l'étude a été menée sur les propriétés de rétention d'eau et le couplage hydro-mécanique du sol par des essais de compression axiale avec suivi de succion par le tensiomètre. Les résultats obtenus ont permis d'élaborer une procédure expérimentale rationnelle pour l'essai triaxial. En second lieu, des systèmes d'essai triaxial à hautes pressions et à température contrôlée ont été développés pour réaliser des essais de compression, de chauffage, et de cisaillement à différentes températures. Les résultats obtenus ont montré clairement le comportement visco-élasto-plastique. Ce comportement a été modélisé en étendant la loi de comportement thermo-élasto-plastique de Cui et al. (2000) à l'effet du fluage.

Nous avons établi une indication chiffrée des coûts réels issus des désinflations basées sur l'ancrage nominal du taux de change. Notre analyse s'est appuyée sur deux régions ayant recouru le plus souvent au taux de change comme instrument de lutte contre l'inflation élevée chronique ou l'hyperinflation : l'Amérique latine et l'Europe centrale et orientale. En général, la stratégie d'ancrage nominal par le change est efficace pour réduire le taux d'inflation. Cette efficacité est plus marquante en Europe centrale et orientale qu'en Amérique latine, où le bilan de désinflation reste mitigé. Quant à son impact sur l'activité économique, les résultats obtenus sont moins évidents. En utilisant deux approches, factuelle et économétrique, nos estimations des ratios de sacrifice des deux régions indiquent que, quel que soit l'ancrage nominal, les coûts de la désinflation sont faibles, voire nuls. Il ressort, cependant, de notre étude, qu'il est difficile d'établir une relation entre les ratios de sacrifice et l'ancrage nominal du taux de change, dans la mesure où les résultats varient d'une méthode d'estimation à l'autre. L'hétérogénéité des ratios de sacrifice rend impossible la comparaison des coûts entre les pays, entre les régions et entre les stratégies d'ancrage nominal. Le choix d'une stratégie désinflationniste ne peut donc pas être basé sur l'analyse des ratios de sacrifice.

Boom and bust cycles are widely documented in the literature on industry dynamics. Rigidities and delays in capacity adjustment in combination with bounded rational behavior have been identified as central driving forces. We construct a model that features only these two elements and we show that this is indeed sufficient to reproduce some stylized facts of a boom and bust cycle. The bifurcation diagrams summarizing the dynamic behavior reveal complex cycles and in particular also abrupt changes in the nature of these cycles. We apply new insights from the mathematical theory of piecewise smooth dynamic systems - in particular, results from the theory of border collision bifurcations - and show that the very existence of borders such as capacity constraints or nonnegativity constraints may lie behind abrupt changes in the dynamic behavior of economic variables. (author's abstract) / Series: Department of Economics Working Paper Series

The accurate determination of gender of biological samples has valuable applications in medical and forensic investigations. Gender determination based on length variations in the X-Y homologous amelogenin gene, is part of most commercial multiplex DNA profiling kits. The first report of a failure of the amelogenin sex test was in 1998 when two normal males were typed as female. Subsequently, several amelogenin Y (AMELY) negative males have been reported. This study represents the first report of this phenomenon in the black South African population. This study determined the size of the Y-chromosome deletion that resulted in the failure of the amelogenin sex test in two black South African AMELY-negative males by typing specific DNA markers surrounding the amelogenin locus. Through deletion size and Y-chromosome microsatellite haplotypes, the relationship between the samples was investigated. The samples were sequenced at the amelogenin gene and typed for thirteen sites on the short arm of the Y-chromosome. In order to determine the Y-chromosome haplotypes, eleven Y-chromosome microsatellite markers were typed. These samples had the same size deletion of approximately 3 Mb. The Y-chromosome haplotypes indicated that these were probably independent events. The frequency of AMELY-negative males is rare in this population sample of 8,344 individuals, with a frequency of 0.065% in the black South African sample population. Notwithstanding, tests performed for detecting the presence of male DNA based on the presence of the amelogenin gene alone should be reconsidered, as this study confirms that these deletions do occur in the African population. The impact of the results generated in this study on the medical and forensic practise of DNA testing is significant. / Thesis (Ph.D. (Biochemistry))--North-West University, Potchefstroom Campus, 2011.

There are many practical decision problems that fall into the category of network flow problems: numerous examples of applications can be found in areas such as telecommunications, logistics, distributions, engineering, computer science and so on. One of the most popular and valuable tools to solve network flow problems of a topological nature is the use of linear programming models. An important extension of these models is that of integer programming models that deal with problems where some, or all, of the variables are required to assume integer variables. A significant application in this class of problems is the knapsack problem that arises in different contexts such as loading containers in aircraft or satisfying the demand for various lengths of cloth which must be cut from fixed length bolts of fabric. In this study, the feasibility of representing a network flow model in a tree network model and subsequently solving it using a tree knapsack approach is investigated. To compare and validate the proposed technique, a specific case study was chosen from the literature that can be used as a basis for the research project. The said study was an oil pipeline design problem, addressed by Brimberg et al. (2003). This focuses on the optimal design of an oil pipeline network for the South Gabon oil field in Africa. The objective was to reduce oil transportation costs to a major port. Following an overview of different network flow and knapsack models, an overview of the said matter is presented. A description of the proposed tree knapsack approach and the application of this approach to the given problem is given. Results have indicated that it is feasible to apply a tree knapsack approach to solve network flow problems. / Thesis (M.Sc. (Computer Science))--North-West University, Potchefstroom Campus, 2011.

The accurate determination of gender of biological samples has valuable applications in medical and forensic investigations. Gender determination based on length variations in the X-Y homologous amelogenin gene, is part of most commercial multiplex DNA profiling kits. The first report of a failure of the amelogenin sex test was in 1998 when two normal males were typed as female. Subsequently, several amelogenin Y (AMELY) negative males have been reported. This study represents the first report of this phenomenon in the black South African population. This study determined the size of the Y-chromosome deletion that resulted in the failure of the amelogenin sex test in two black South African AMELY-negative males by typing specific DNA markers surrounding the amelogenin locus. Through deletion size and Y-chromosome microsatellite haplotypes, the relationship between the samples was investigated. The samples were sequenced at the amelogenin gene and typed for thirteen sites on the short arm of the Y-chromosome. In order to determine the Y-chromosome haplotypes, eleven Y-chromosome microsatellite markers were typed. These samples had the same size deletion of approximately 3 Mb. The Y-chromosome haplotypes indicated that these were probably independent events. The frequency of AMELY-negative males is rare in this population sample of 8,344 individuals, with a frequency of 0.065% in the black South African sample population. Notwithstanding, tests performed for detecting the presence of male DNA based on the presence of the amelogenin gene alone should be reconsidered, as this study confirms that these deletions do occur in the African population. The impact of the results generated in this study on the medical and forensic practise of DNA testing is significant. / Thesis (Ph.D. (Biochemistry))--North-West University, Potchefstroom Campus, 2011.