Heading for the hills: risk avoidance drives den site selection in African wild dogs.

Science.gov (United States)

Jackson, Craig R; Power, R John; Groom, Rosemary J; Masenga, Emmanuel H; Mjingo, Ernest E; Fyumagwa, Robert D; Røskaft, Eivin; Davies-Mostert, Harriet

2014-01-01

Compared to their main competitors, African wild dogs (Lycaon pictus) have inferior competitive abilities and interspecific competition is a serious fitness-limiting factor. Lions (Panthera leo) are the dominant large carnivore in African savannah ecosystems and wild dogs avoid them both spatially and temporally. Wild dog young are particularly vulnerable and suffer high rates of mortality from lions. Since lions do not utilize all parts of the landscape with an equal intensity, spatial variation in lion densities can be exploited by wild dogs both during their general ranging behaviour, but more specifically when they are confined to a den with vulnerable young. Since patches of rugged terrain are associated with lower lion densities, we hypothesized that these comparatively safe habitats should be selected by wild dogs for denning. We investigated the relationship between the distribution of 100 wild dog den sites and the occurrence of rugged terrain in four wild dog populations located in Tanzania, Zimbabwe and South Africa. A terrain ruggedness index was derived from a 90 m digital elevation model and used to map terrain ruggedness at each site. We compared characteristics of actual and potential (random) den sites to determine how wild dogs select den sites. The distributions of wild dog dens were strongly associated with rugged terrain and wild dogs actively selected terrain that was more rugged than that available on average. The likelihood of encountering lions is reduced in these habitats, minimizing the risk to both adults and pups. Our findings have important implications for the conservation management of the species, especially when assessing habitat suitability for potential reintroductions. The simple technique used to assess terrain ruggedness may be useful to investigate habitat suitability, and even predict highly suitable denning areas, across large landscapes.

Heading for the hills: risk avoidance drives den site selection in African wild dogs.

Directory of Open Access Journals (Sweden)

Craig R Jackson

Full Text Available Compared to their main competitors, African wild dogs (Lycaon pictus have inferior competitive abilities and interspecific competition is a serious fitness-limiting factor. Lions (Panthera leo are the dominant large carnivore in African savannah ecosystems and wild dogs avoid them both spatially and temporally. Wild dog young are particularly vulnerable and suffer high rates of mortality from lions. Since lions do not utilize all parts of the landscape with an equal intensity, spatial variation in lion densities can be exploited by wild dogs both during their general ranging behaviour, but more specifically when they are confined to a den with vulnerable young. Since patches of rugged terrain are associated with lower lion densities, we hypothesized that these comparatively safe habitats should be selected by wild dogs for denning. We investigated the relationship between the distribution of 100 wild dog den sites and the occurrence of rugged terrain in four wild dog populations located in Tanzania, Zimbabwe and South Africa. A terrain ruggedness index was derived from a 90 m digital elevation model and used to map terrain ruggedness at each site. We compared characteristics of actual and potential (random den sites to determine how wild dogs select den sites. The distributions of wild dog dens were strongly associated with rugged terrain and wild dogs actively selected terrain that was more rugged than that available on average. The likelihood of encountering lions is reduced in these habitats, minimizing the risk to both adults and pups. Our findings have important implications for the conservation management of the species, especially when assessing habitat suitability for potential reintroductions. The simple technique used to assess terrain ruggedness may be useful to investigate habitat suitability, and even predict highly suitable denning areas, across large landscapes.

African American Veterans Storytelling: A Multisite Randomized Trial to Improve Hypertension.

Science.gov (United States)

Houston, Thomas K; Fix, Gemmae M; Shimada, Stephanie L; Long, Judith A; Gordon, Howard S; Pope, Charlene; Volkman, Julie; Allison, Jeroan J; DeLaughter, Kathryn; Orner, Michelle; Bokhour, Barbara G

2017-09-01

Disparities in hypertension control persist for African American Veterans. To enhance cultural relevance of hypertension control self-management education, in a multisite, stratified randomized trial, we tested an interactive Veteran-to-Veteran storytelling digital video disk (DVD) intervention created with Veteran partners, versus an education-only DVD comparison. At 3 VA facilities, African American Veterans with uncontrolled hypertension were randomized to storytelling DVD intervention or didactic comparison DVD and followed for 6 months. We hypothesized that follow-up blood pressure (BP) would be lower among Veterans in the intervention group. African American Veterans (N=619) were 92% male, 39% over age 65, most had a high-school education, over 50% of both the intervention and comparison group reported a household income of 0.3). Site differences were large; at one, the intervention group improved while the comparison groups deteriorated, resulting in 6.3 and 3.9 mm Hg more improvement for the intervention group in SBP and diastolic BP (P=0.06 and 0.04), respectively; at the other 2 sites, there were positive and negative changes, all small, in the 2 measures, with minimal differences-one site favored the comparison group and the other, the intervention (these comparisons did not approach statistical significance (all P>0.20). In a secondary analysis stratified by baseline BP, there was no intervention effect among those with uncontrolled BP, but intervention patients who were in control at baseline were more likely to stay in control, compared with comparison [SBP increase by 6.3 mm Hg (SD=14.4) among intervention, and by 10.9 mm Hg (SD=16.9) in comparison, P=0.02]. In this multisite trial, we did not find a significant overall storytelling intervention effect (Clinicaltrials.gov Reg. #NCT01276197).

Relationship between Early Familial Influences and Personality Traits in Relation to Career Success Outcomes of African American Women

Science.gov (United States)

Gardner, Keeba G.

2010-01-01

This study will examine the relationship between career success outcomes of African American women and early familial factors, as well as personality traits. Using a cross-sectional case-control design. the study will use participants who self-identified as African American with two African American parents. They will be randomly selected from a…

Estimation of the ancestral effective population sizes of African great apes under different selection regimes.

Science.gov (United States)

Schrago, Carlos G

2014-08-01

Reliable estimates of ancestral effective population sizes are necessary to unveil the population-level phenomena that shaped the phylogeny and molecular evolution of the African great apes. Although several methods have previously been applied to infer ancestral effective population sizes, an analysis of the influence of the selective regime on the estimates of ancestral demography has not been thoroughly conducted. In this study, three independent data sets under different selective regimes were used were composed to tackle this issue. The results showed that selection had a significant impact on the estimates of ancestral effective population sizes of the African great apes. The inference of the ancestral demography of African great apes was affected by the selection regime. The effects, however, were not homogeneous along the ancestral populations of great apes. The effective population size of the ancestor of humans and chimpanzees was more impacted by the selection regime when compared to the same parameter in the ancestor of humans, chimpanzees and gorillas. Because the selection regime influenced the estimates of ancestral effective population size, it is reasonable to assume that a portion of the discrepancy found in previous studies that inferred the ancestral effective population size may be attributable to the differential action of selection on the genes sampled.

Strong selection during the last millennium for African ancestry in the admixed population of Madagascar.

Science.gov (United States)

Pierron, Denis; Heiske, Margit; Razafindrazaka, Harilanto; Pereda-Loth, Veronica; Sanchez, Jazmin; Alva, Omar; Arachiche, Amal; Boland, Anne; Olaso, Robert; Deleuze, Jean-Francois; Ricaut, Francois-Xavier; Rakotoarisoa, Jean-Aimé; Radimilahy, Chantal; Stoneking, Mark; Letellier, Thierry

2018-03-02

While admixed populations offer a unique opportunity to detect selection, the admixture in most of the studied populations occurred too recently to produce conclusive signals. By contrast, Malagasy populations originate from admixture between Asian and African populations that occurred ~27 generations ago, providing power to detect selection. We analyze local ancestry across the genomes of 700 Malagasy and identify a strong signal of recent positive selection, with an estimated selection coefficient >0.2. The selection is for African ancestry and affects 25% of chromosome 1, including the Duffy blood group gene. The null allele at this gene provides resistance to Plasmodium vivax malaria, and previous studies have suggested positive selection for this allele in the Malagasy population. This selection event also influences numerous other genes implicated in immunity, cardiovascular diseases, and asthma and decreases the Asian ancestry genome-wide by 10%, illustrating the role played by selection in recent human history.

A Dietary Intervention in Urban African Americans: Results of the "Five Plus Nuts and Beans" Randomized Trial.

Science.gov (United States)

Miller, Edgar R; Cooper, Lisa A; Carson, Kathryn A; Wang, Nae-Yuh; Appel, Lawrence J; Gayles, Debra; Charleston, Jeanne; White, Karen; You, Na; Weng, Yingjie; Martin-Daniels, Michelle; Bates-Hopkins, Barbara; Robb, Inez; Franz, Whitney K; Brown, Emily L; Halbert, Jennifer P; Albert, Michael C; Dalcin, Arlene T; Yeh, Hsin-Chieh

2016-01-01

Unhealthy diets, often low in potassium, likely contribute to racial disparities in blood pressure. We tested the effectiveness of providing weekly dietary advice, assistance with selection of higher potassium grocery items, and a $30 per week food allowance on blood pressure and other outcomes in African American adults with hypertension. We conducted an 8-week RCT with two parallel arms between May 2012 and November 2013. We randomized 123 African Americans with controlled hypertension from an urban primary care clinic in Baltimore, Maryland, and implemented the trial in partnership with a community supermarket and the Baltimore City Health Department. Mean (SD) age was 58.6 (9.5) years; 71% were female; blood pressure was 131.3 (14.7)/77.2 (10.5) mmHg; BMI was 34.5 (8.2); and 28% had diabetes. Participants randomized to the active intervention group (Dietary Approaches to Stop Hypertension [DASH]-Plus) received coach-directed dietary advice and assistance with weekly online ordering and purchasing of high-potassium foods ($30/week) delivered by a community supermarket to a neighborhood library. Participants in the control group received a printed DASH diet brochure along with a debit account of equivalent value to that of the DASH-Plus group. The primary outcome was blood pressure change. Analyses were conducted in January to October 2014. Compared with the control group, the DASH-Plus group increased self-reported consumption of fruits and vegetables (mean=1.4, 95% CI=0.7, 2.1 servings/day); estimated intake of potassium (mean=0.4, 95% CI=0.1, 0.7 grams/day); and urine potassium excretion (mean=19%, 95% CI=1%, 38%). There was no significant effect on blood pressure. A program providing dietary advice, assistance with grocery ordering, and $30/week of high-potassium foods in African American patients with controlled hypertension in a community-based clinic did not reduce BP. However, the intervention increased consumption of fruits, vegetables, and urinary

An approach to product selection for insomnia | Smith | South African ...

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 55, No 5 (2013) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Exposure to lead in South African shooting ranges

International Nuclear Information System (INIS)

Mathee, Angela; Jager, Pieter de; Naidoo, Shan; Naicker, Nisha

2017-01-01

Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

Exposure to lead in South African shooting ranges

Energy Technology Data Exchange (ETDEWEB)

Mathee, Angela [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg (Environmental Health Department, Faculty of Health Sciences), PO Box 524, Auckland Park, Johannesburg 2006 (South Africa); Jager, Pieter de [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); National Health Laboratory Service (Epidemiology and Surveillance Unit, National Institute for Occupational Health), PO Box 4788, Johannesburg 2000 (South Africa); Naidoo, Shan [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); Naicker, Nisha [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand, School of Public Health, PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg, Environmental Health Department, Faculty of Health Sciences, PO Box 524, Auckland Park, Johannesburg 2006 (South Africa)

2017-02-15

Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

The Influence of Spiritual Framing on African American Women's Mammography Intentions: A Randomized Trial.

Science.gov (United States)

Best, Alicia L; Spencer, S Melinda; Friedman, Daniela B; Hall, Ingrid J; Billings, Deborah

2016-06-01

Spiritual framing of breast cancer communication may provide a useful strategy for addressing disparate rates of breast cancer mortality among African American women. The efficacy of a spiritually framed breast cancer screening (BCS) message was compared with that of a traditional BCS message. Specifically, 200 African American women were randomly assigned to review either a spiritually framed or traditional BCS message and complete a self-administered survey, including a thought-listing form. Message efficacy was measured by number of thoughts generated (elaboration), ratio of positive to negative thoughts (polarity), and intention to obtain and/or recommend a mammogram. Multiple linear regression and structural equation modeling were used to assess direct and indirect (mediated) associations among variables. Spiritual framing was positively associated with greater elaboration (β = .265, SE = .36, p framing also had a significant indirect effect on mammography intentions through polarity (standardized indirect effect = .057, 95% confidence interval [.024, .106], p framing may improve the efficacy of BCS messages among African American women by eliciting more positive thoughts about screening. Interventions targeting African American women might consider the role of spirituality when tailoring messages to encourage regular mammography use.

Some aspects of gender inequality in selected African literary texts

Directory of Open Access Journals (Sweden)

L.L. Kwatsha

2009-07-01

Full Text Available This article focuses on gender inequalities in selected African literary texts. I explore the way in which some African writers view gender inequalities and stereotypes in their characters. We will also be able to see who is involved and affected by these gender inequalities and how. Gender theory will be used as a framework. The aspects of gender that are discussed, include gender stereotypes, gender roles, gender identity, the superiority of men, inequality in polygamous marriages, sex roles, the sexual division of labour and arranged marriage. This study will also include the views of writers from other part of Africa. These views have a lot in common but sometimes they vary because of the influence and different ideologies of the society concerned.

Selectivity and sparseness in randomly connected balanced networks.

Directory of Open Access Journals (Sweden)

Cengiz Pehlevan

Full Text Available Neurons in sensory cortex show stimulus selectivity and sparse population response, even in cases where no strong functionally specific structure in connectivity can be detected. This raises the question whether selectivity and sparseness can be generated and maintained in randomly connected networks. We consider a recurrent network of excitatory and inhibitory spiking neurons with random connectivity, driven by random projections from an input layer of stimulus selective neurons. In this architecture, the stimulus-to-stimulus and neuron-to-neuron modulation of total synaptic input is weak compared to the mean input. Surprisingly, we show that in the balanced state the network can still support high stimulus selectivity and sparse population response. In the balanced state, strong synapses amplify the variation in synaptic input and recurrent inhibition cancels the mean. Functional specificity in connectivity emerges due to the inhomogeneity caused by the generative statistical rule used to build the network. We further elucidate the mechanism behind and evaluate the effects of model parameters on population sparseness and stimulus selectivity. Network response to mixtures of stimuli is investigated. It is shown that a balanced state with unselective inhibition can be achieved with densely connected input to inhibitory population. Balanced networks exhibit the "paradoxical" effect: an increase in excitatory drive to inhibition leads to decreased inhibitory population firing rate. We compare and contrast selectivity and sparseness generated by the balanced network to randomly connected unbalanced networks. Finally, we discuss our results in light of experiments.

Adolescent alcohol use in rural South African high schools | Onya ...

African Journals Online (AJOL)

Objective: To examine psychosocial correlates of lifetime alcohol use among adolescents in rural South African high schools. Method: Questionnaires were administered to 1600 students from 20 randomly selected high schools in the Mankweng district within Limpopo province. Self-report data on alcohol use, demographic, ...

A preliminary study investigating the factors influencing STEM major selection by African American females

Science.gov (United States)

Ray, Tiffany Monique

The purpose of this study was to investigate the significant factors influencing STEM major selection by African American females. A quantitative research design with a qualitative component was employed. Ex post facto survey research was conducted utilizing an online questionnaire to collect data from participants. African American undergraduate females that had declared a major in STEM comprised the target population for the study. As a basis for comparison, a second data collection ensued. All non-African American undergraduate females majoring in STEM also received the survey instrument to determine if there was a significant difference between factors that influence STEM major selection between the two groups. The Social Cognitive Career Choice Model comprised the conceptual framework for this study. Frequencies and percentages illustrated the demographic characteristics of the sample, as well as the average influence levels of each of the items without regard for level of significance. The researcher conducted an independent samples t-test to compare the mean scores for undergraduate African American females majoring in STEM and non-African American females majoring in STEM on each influential factor on the survey instrument. The researcher coded responses to open-ended questions to generate themes and descriptions. The data showed that African American female respondents were very influenced by the following items: specific interest in the subject, type of work, availability of career opportunities after graduation, parent/guardian, precollege coursework in science, and introductory college courses. In addition, the majority of respondents were very influenced by each of the confidence factors. African American females were overwhelmingly not influenced by aptitude tests. African American females were more influenced than their non-African American female counterparts for the following factors: reputation of the university, college or department, high level

Testing, Selection, and Implementation of Random Number Generators

National Research Council Canada - National Science Library

Collins, Joseph C

2008-01-01

An exhaustive evaluation of state-of-the-art random number generators with several well-known suites of tests provides the basis for selection of suitable random number generators for use in stochastic simulations...

Stock Market Integration in Africa: The Case of the Johannesburg Stock Exchange and Selected African Countries

OpenAIRE

Gail Ncube; Kapingura Forget Mingiri

2015-01-01

African stock markets are deemed to be small, segmented and illiquid. Given this back ground, the study utilises monthly data for the period 2000-2008, employing the Johansen and Julius cointegration method to determine the long-run relationship between the five selected African stock markets. Granger causality tests were also conducted to establish if there are any causal links between the stock markets in Africa. The analysis in the study indicates that African stock markets are improving i...

Perceived value in food selection when dining out: comparison of African Americans and Euro-Americans.

Science.gov (United States)

Vinci, Debra M; Philipp, Steven F

2007-06-01

This descriptive study compares African Americans' and Euro-Americans' perceived value of food selection pertaining to cost, portion size, and meal satisfaction when eating away from home. A stratified sample was drawn from a southern U.S. metropolitan area (N= 1,011; 486 African American, 525 Euro-American). Analysis showed no difference between African-American and Euro-American adults by sex or how often they dined out. These two groups significantly differed across years of education, age, and answering 14 of 18 rated statements on value perceptions. African-Americans' value perceptions were influenced more by lower cost foods and larger portion sizes than those of Euro-Americans. For meal satisfaction, African Americans were more likely to agree with statements that indicate preferring foods high in energy and low in essential micronutrient density. This study supports the need for more investigation.

An overview of the Families Improving Together (FIT) for weight loss randomized controlled trial in African American families.

Science.gov (United States)

Wilson, Dawn K; Kitzman-Ulrich, Heather; Resnicow, Ken; Van Horn, M Lee; St George, Sara M; Siceloff, E Rebekah; Alia, Kassandra A; McDaniel, Tyler; Heatley, VaShawn; Huffman, Lauren; Coulon, Sandra; Prinz, Ron

2015-05-01

The Families Improving Together (FIT) randomized controlled trial tests the efficacy of integrating cultural tailoring, positive parenting, and motivational strategies into a comprehensive curriculum for weight loss in African American adolescents. The overall goal of the FIT trial is to test the effects of an integrated intervention curriculum and the added effects of a tailored web-based intervention on reducing z-BMI in overweight African American adolescents. The FIT trial is a randomized group cohort design the will involve 520 African American families with an overweight adolescent between the ages of 11-16 years. The trial tests the efficacy of an 8-week face-to-face group randomized program comparing M + FWL (Motivational Plus Family Weight Loss) to a comprehensive health education program (CHE) and re-randomizes participants to either an 8-week on-line tailored intervention or control on-line program resulting in a 2 (M + FWL vs. CHE group) × 2 (on-line intervention vs. control on-line program) factorial design to test the effects of the intervention on reducing z-BMI at post-treatment and at 6-month follow-up. The interventions for this trial are based on a theoretical framework that is novel and integrates elements from cultural tailoring, Family Systems Theory, Self-Determination Theory and Social Cognitive Theory. The intervention targets positive parenting skills (parenting style, monitoring, communication); cultural values; teaching parents to increase youth motivation by encouraging youth to have input and choice (autonomy-support); and provides a framework for building skills and self-efficacy through developing weight loss action plans that target goal setting, monitoring, and positive feedback. Copyright © 2015. Published by Elsevier Inc.

Stress Management-Augmented Behavioral Weight Loss Intervention for African American Women: A Pilot, Randomized Controlled Trial

Science.gov (United States)

Cox, Tiffany L.; Krukowski, Rebecca; Love, ShaRhonda J.; Eddings, Kenya; DiCarlo, Marisha; Chang, Jason Y.; Prewitt, T. Elaine; West, Delia Smith

2013-01-01

The relationship between chronic stress and weight management efforts may be a concern for African American (AA) women, who have a high prevalence of obesity, high stress levels, and modest response to obesity treatment. This pilot study randomly assigned 44 overweight/obese AA women with moderate to high stress levels to either a 12-week…

Application of random effects to the study of resource selection by animals.

Science.gov (United States)

Gillies, Cameron S; Hebblewhite, Mark; Nielsen, Scott E; Krawchuk, Meg A; Aldridge, Cameron L; Frair, Jacqueline L; Saher, D Joanne; Stevens, Cameron E; Jerde, Christopher L

2006-07-01

1. Resource selection estimated by logistic regression is used increasingly in studies to identify critical resources for animal populations and to predict species occurrence. 2. Most frequently, individual animals are monitored and pooled to estimate population-level effects without regard to group or individual-level variation. Pooling assumes that both observations and their errors are independent, and resource selection is constant given individual variation in resource availability. 3. Although researchers have identified ways to minimize autocorrelation, variation between individuals caused by differences in selection or available resources, including functional responses in resource selection, have not been well addressed. 4. Here we review random-effects models and their application to resource selection modelling to overcome these common limitations. We present a simple case study of an analysis of resource selection by grizzly bears in the foothills of the Canadian Rocky Mountains with and without random effects. 5. Both categorical and continuous variables in the grizzly bear model differed in interpretation, both in statistical significance and coefficient sign, depending on how a random effect was included. We used a simulation approach to clarify the application of random effects under three common situations for telemetry studies: (a) discrepancies in sample sizes among individuals; (b) differences among individuals in selection where availability is constant; and (c) differences in availability with and without a functional response in resource selection. 6. We found that random intercepts accounted for unbalanced sample designs, and models with random intercepts and coefficients improved model fit given the variation in selection among individuals and functional responses in selection. Our empirical example and simulations demonstrate how including random effects in resource selection models can aid interpretation and address difficult assumptions

Local randomization in neighbor selection improves PRM roadmap quality

KAUST Repository

McMahon, Troy; Jacobs, Sam; Boyd, Bryan; Tapia, Lydia; Amato, Nancy M.

2012-01-01

Probabilistic Roadmap Methods (PRMs) are one of the most used classes of motion planning methods. These sampling-based methods generate robot configurations (nodes) and then connect them to form a graph (roadmap) containing representative feasible pathways. A key step in PRM roadmap construction involves identifying a set of candidate neighbors for each node. Traditionally, these candidates are chosen to be the k-closest nodes based on a given distance metric. In this paper, we propose a new neighbor selection policy called LocalRand(k,K'), that first computes the K' closest nodes to a specified node and then selects k of those nodes at random. Intuitively, LocalRand attempts to benefit from random sampling while maintaining the higher levels of local planner success inherent to selecting more local neighbors. We provide a methodology for selecting the parameters k and K'. We perform an experimental comparison which shows that for both rigid and articulated robots, LocalRand results in roadmaps that are better connected than the traditional k-closest policy or a purely random neighbor selection policy. The cost required to achieve these results is shown to be comparable to k-closest. © 2012 IEEE.

Local randomization in neighbor selection improves PRM roadmap quality

KAUST Repository

McMahon, Troy

2012-10-01

Probabilistic Roadmap Methods (PRMs) are one of the most used classes of motion planning methods. These sampling-based methods generate robot configurations (nodes) and then connect them to form a graph (roadmap) containing representative feasible pathways. A key step in PRM roadmap construction involves identifying a set of candidate neighbors for each node. Traditionally, these candidates are chosen to be the k-closest nodes based on a given distance metric. In this paper, we propose a new neighbor selection policy called LocalRand(k,K\\'), that first computes the K\\' closest nodes to a specified node and then selects k of those nodes at random. Intuitively, LocalRand attempts to benefit from random sampling while maintaining the higher levels of local planner success inherent to selecting more local neighbors. We provide a methodology for selecting the parameters k and K\\'. We perform an experimental comparison which shows that for both rigid and articulated robots, LocalRand results in roadmaps that are better connected than the traditional k-closest policy or a purely random neighbor selection policy. The cost required to achieve these results is shown to be comparable to k-closest. © 2012 IEEE.

Improving urban African Americans' blood pressure control through multi-level interventions in the Achieving Blood Pressure Control Together (ACT) study: a randomized clinical trial.

Science.gov (United States)

Ephraim, Patti L; Hill-Briggs, Felicia; Roter, Debra L; Bone, Lee R; Wolff, Jennifer L; Lewis-Boyer, LaPricia; Levine, David M; Aboumatar, Hanan J; Cooper, Lisa A; Fitzpatrick, Stephanie J; Gudzune, Kimberly A; Albert, Michael C; Monroe, Dwyan; Simmons, Michelle; Hickman, Debra; Purnell, Leon; Fisher, Annette; Matens, Richard; Noronha, Gary J; Fagan, Peter J; Ramamurthi, Hema C; Ameling, Jessica M; Charlston, Jeanne; Sam, Tanyka S; Carson, Kathryn A; Wang, Nae-Yuh; Crews, Deidra C; Greer, Raquel C; Sneed, Valerie; Flynn, Sarah J; DePasquale, Nicole; Boulware, L Ebony

2014-07-01

Given their high rates of uncontrolled blood pressure, urban African Americans comprise a particularly vulnerable subgroup of persons with hypertension. Substantial evidence has demonstrated the important role of family and community support in improving patients' management of a variety of chronic illnesses. However, studies of multi-level interventions designed specifically to improve urban African American patients' blood pressure self-management by simultaneously leveraging patient, family, and community strengths are lacking. We report the protocol of the Achieving Blood Pressure Control Together (ACT) study, a randomized controlled trial designed to study the effectiveness of interventions that engage patient, family, and community-level resources to facilitate urban African American hypertensive patients' improved hypertension self-management and subsequent hypertension control. African American patients with uncontrolled hypertension receiving health care in an urban primary care clinic will be randomly assigned to receive 1) an educational intervention led by a community health worker alone, 2) the community health worker intervention plus a patient and family communication activation intervention, or 3) the community health worker intervention plus a problem-solving intervention. All participants enrolled in the study will receive and be trained to use a digital home blood pressure machine. The primary outcome of the randomized controlled trial will be patients' blood pressure control at 12months. Results from the ACT study will provide needed evidence on the effectiveness of comprehensive multi-level interventions to improve urban African American patients' hypertension control. Copyright © 2014 Elsevier Inc. All rights reserved.

Technology-Intensified Diabetes Education Study (TIDES) in African Americans with type 2 diabetes: study protocol for a randomized controlled trial.

Science.gov (United States)

Williams, Joni S; Lynch, Cheryl P; Knapp, Rebecca G; Egede, Leonard E

2014-11-25

Compared to American Whites, African Americans have a higher prevalence of type 2 diabetes mellitus (T2DM), experiencing poorer metabolic control and greater risks for complications and death. Patient-level factors, such as diabetes knowledge, self-management skills, empowerment, and perceived control, account for >90% of the variance observed in outcomes between these racial groups. There is strong evidence that self-management interventions that include telephone-delivered diabetes education and skills training are effective at improving metabolic control in diabetes. Web-based home telemonitoring systems in conjunction with active care management are also effective ways to lower glycosylated hemoglobin A1c values when compared to standard care, and provide feedback to patients; however, there are no studies in African Americans with poorly controlled T2DM that examine the use of technology-based feedback to tailor or augment diabetes education and skills training. This study provides a unique opportunity to address this gap in the literature. We describe an ongoing 4-year randomized clinical trial, which will test the efficacy of a technology-intensified diabetes education and skills training (TIDES) intervention in African Americans with poorly controlled T2DM. Two hundred male and female AfricanAmerican participants, 21 years of age or older and with a glycosylated hemoglobin A1c level ≥ 8%, will be randomized into one of two groups for 12 weeks of telephone interventions: (1) TIDES intervention group or (2) a usual-care group. Participants will be followed for 12 months to ascertain the effect of the interventions on glycemic control. Our primary hypothesis is that, among African Americans with poorly controlled T2DM, patients randomized to the TIDES intervention will have significantly greater reduction in glycosylated hemoglobin A1c at 12 months of follow-up compared to the usual-care group. Results from this study will add to the current literature

Systematic review of stigma reducing interventions for African/Black diasporic women.

Science.gov (United States)

Loutfy, Mona; Tharao, Wangari; Logie, Carmen; Aden, Muna A; Chambers, Lori A; Wu, Wei; Abdelmaseh, Marym; Calzavara, Liviana

2015-01-01

Literature indicates that racism, sexism, homophobia and HIV-related stigma have adverse impacts on health, well-being, and quality of life among HIV-positive women of African descent (African/Black diaspora). However, limited evidence exists on the effectiveness of interventions aimed at reducing stigma tailored for these women. This study systematically reviewed randomized controlled trials (RCTs), non-randomized observational and quasi-experimental studies evaluating the effectiveness of interventions aimed at reducing stigma experienced by this population. The Cochrane methodology was used to develop a search strategy in consultation with a librarian scientist. Databases searched included the Cochrane Library, Ovid EMBASE, PsycInfo, and 10 others. Two reviewers independently assessed the studies for potential relevance and conducted the Cochrane grading of RCTs to assess risk of bias and the Newcastle-Ottawa scale to assess the quality of non-randomized studies. Eligible papers were selected if they employed an intervention design with African/Black diasporic women living with HIV as the target population and had a primary outcome of stigma reduction. Of the five studies that met all of the eligibility criteria, four demonstrated the effectiveness of interventions in reducing HIV-related stigma. Only two of the five studies were designed specifically for HIV-positive African/Black diasporic women. Limitations included the absence of interventions addressing other forms of stigma and discrimination (e.g. gender discrimination, racism, heterosexism). Our findings suggest that there are limited interventions designed to address multiple forms of stigma, including gender and racial discrimination, experienced by HIV-positive African/Black diasporic women.

Phytochemical analysis and biological evaluation of selected African propolis samples from Cameroon and Congo

NARCIS (Netherlands)

Papachroni, D.; Graikou, K.; Kosalec, I.; Damianakos, H.; Ingram, V.J.; Chinou, I.

2015-01-01

The objective of this study was the chemical analysis of four selected samples of African propolis (Congo and Cameroon) and their biological evaluation. Twenty-one secondary metabolites belonging to four different chemical groups were isolated from the 70% ethanolic extracts of propolis and their

Impact of Selection Practices on Career Advancement of African American Women in Community College Administration

Science.gov (United States)

Yancy-Tooks, Barbara J.

2012-01-01

The purpose of this qualitative ethnographic study was to explore the experiences of African American women about their perceptions of factors (i.e. senior administrator selection practices, institutional practices, barriers, and coping strategies) that hinder or facilitate advancement in community college administration. The following questions…

African Diaspora Associations in Denmark

DEFF Research Database (Denmark)

Vammen, Ida Marie; Trans, Lars Ove

2011-01-01

Since the early 1990s, an increasing number of African migrants have come to Denmark, where they have formed a large number of migrant associations. This chapter presents selected findings from a comprehensive survey of African diaspora associations in Denmark and focuses specifically on their tr......Since the early 1990s, an increasing number of African migrants have come to Denmark, where they have formed a large number of migrant associations. This chapter presents selected findings from a comprehensive survey of African diaspora associations in Denmark and focuses specifically...

Herbaceous forage and selection patterns by ungulates across varying herbivore assemblages in a South African savanna

NARCIS (Netherlands)

Treydte, A.C.; Baumgartner, S.; Heitkonig, I.M.A.; Grant, C.C.; Getz, W.M.

2013-01-01

Herbivores generally have strong structural and compositional effects on vegetation, which in turn determines the plant forage species available. We investigated how selected large mammalian herbivore assemblages use and alter herbaceous vegetation structure and composition in a southern African

Efficacy of an HIV/STI sexual risk-reduction intervention for African American adolescent girls in juvenile detention centers: a randomized controlled trial.

Science.gov (United States)

DiClemente, Ralph J; Davis, Teaniese L; Swartzendruber, Andrea; Fasula, Amy M; Boyce, Lorin; Gelaude, Deborah; Gray, Simone C; Hardin, James; Rose, Eve; Carry, Monique; Sales, Jessica M; Brown, Jennifer L; Staples-Horne, Michelle

2014-01-01

Few HIV/STI interventions exist for African American adolescent girls in juvenile detention. The objective was to evaluate the efficacy of an intervention to reduce incident STIs, improve HIV-preventive behaviors, and enhance psychosocial outcomes. We conducted a randomized controlled trial among African American adolescent girls (13-17 years, N = 188) in juvenile detention from March 2011 to May 2012. Assessments occurred at baseline and 3- and 6-months post-randomization and included: audio computer-assisted self-interview, condom skills assessment, and self-collected vaginal swab to detect Chlamydia and gonorrhea. The Imara intervention included three individual-level sessions and four phone sessions; expedited partner therapy was offered to STI-positive adolescents. The comparison group received the usual care provided by the detention center: STI testing, treatment, and counseling. At the 6-month assessment (3-months post-intervention), Imara participants reported higher condom use self-efficacy (p incident Chlamydia or gonorrhea infections, condom use, or number of vaginal sex partners. Imara for detained African American adolescent girls can improve condom use skills and psychosocial outcomes; however, a critical need for interventions to reduce sexual risk remains.

African bees to control African elephants

Science.gov (United States)

Vollrath, Fritz; Douglas-Hamilton, Iain

2002-11-01

Numbers of elephants have declined in Africa and Asia over the past 30 years while numbers of humans have increased, both substantially. Friction between these two keystone species is reaching levels which are worryingly high from an ecological as well as a political viewpoint. Ways and means must be found to keep the two apart, at least in areas sensitive to each species' survival. The aggressive African bee might be one such method. Here we demonstrate that African bees deter elephants from damaging the vegetation and trees which house their hives. We argue that bees can be employed profitably to protect not only selected trees, but also selected areas, from elephant damage.

South African consumers' opinions and consumption of soy and soy products

OpenAIRE

Badham, Jane; Jerling, Johann C; Bosman, Magdalena J C; Harmse, Naomi; Bouwer, Susanna C; Ellis, Susanna M; Erasmus, Alet C

2009-01-01

Studies linking diet and health and consumers’ demand for health information, has led to an increasing awareness of the role of nutrition in health and disease. Interest in soy foods and an awareness of its health benefits has also increased. The objective was to assess South African (SA) consumers’ opinions and beliefs regarding the health benefits of soy and soy products using different statements. This cross-sectional study randomly selected 3001 respondents from metropolita...

40 CFR 761.308 - Sample selection by random number generation on any two-dimensional square grid.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sample selection by random number... § 761.79(b)(3) § 761.308 Sample selection by random number generation on any two-dimensional square... area created in accordance with paragraph (a) of this section, select two random numbers: one each for...

Peer mentoring and financial incentives to improve glucose control in African American veterans: a randomized trial.

Science.gov (United States)

Long, Judith A; Jahnle, Erica C; Richardson, Diane M; Loewenstein, George; Volpp, Kevin G

2012-03-20

Compared with white persons, African Americans have a greater incidence of diabetes, decreased control, and higher rates of microvascular complications. A peer mentorship model could be a scalable approach to improving control in this population and reducing disparities in diabetic outcomes. To determine whether peer mentors or financial incentives are superior to usual care in helping African American veterans decrease their hemoglobin A(1c) (HbA(1c)) levels. A 6-month randomized, controlled trial. (ClinicalTrials.gov registration number: NCT01125956) Philadelphia Veterans Affairs Medical Center. African American veterans aged 50 to 70 years with persistently poor diabetes control. 118 patients were randomly assigned to 1 of 3 groups: usual care, a peer mentoring group, and a financial incentives group. Usual care patients were notified of their starting HbA(1c) level and recommended goals for HbA(1c). Those in the peer mentoring group were assigned a mentor who formerly had poor glycemic control but now had good control (HbA(1c) level ≤7.5%). The mentor was asked to talk with the patient at least once per week. Peer mentors were matched by race, sex, and age. Patients in the financial incentive group could earn $100 by decreasing their HbA(1c) level by 1% and $200 by decreasing it by 2% or to an HbA(1c) level of 6.5%. Change in HbA(1c) level at 6 months. Mentors and mentees talked the most in the first month (mean calls, 4; range, 0 to 30), but calls decreased to a mean of 2 calls (range, 0 to 10) by the sixth month. Levels of HbA(1c) decreased from 9.9% to 9.8% in the control group, from 9.8% to 8.7% in the peer mentor group, and from 9.5% to 9.1% in the financial incentive group. Mean change in HbA(1c) level from baseline to 6 months relative to control was -1.07% (95% CI, -1.84% to -0.31%) in the peer mentor group and -0.45% (CI, -1.23% to 0.32%) in the financial incentive group. The study included only veterans and lasted only 6 months. Peer mentorship

Applications of random forest feature selection for fine-scale genetic population assignment.

Science.gov (United States)

Sylvester, Emma V A; Bentzen, Paul; Bradbury, Ian R; Clément, Marie; Pearce, Jon; Horne, John; Beiko, Robert G

2018-02-01

Genetic population assignment used to inform wildlife management and conservation efforts requires panels of highly informative genetic markers and sensitive assignment tests. We explored the utility of machine-learning algorithms (random forest, regularized random forest and guided regularized random forest) compared with F ST ranking for selection of single nucleotide polymorphisms (SNP) for fine-scale population assignment. We applied these methods to an unpublished SNP data set for Atlantic salmon ( Salmo salar ) and a published SNP data set for Alaskan Chinook salmon ( Oncorhynchus tshawytscha ). In each species, we identified the minimum panel size required to obtain a self-assignment accuracy of at least 90% using each method to create panels of 50-700 markers Panels of SNPs identified using random forest-based methods performed up to 7.8 and 11.2 percentage points better than F ST -selected panels of similar size for the Atlantic salmon and Chinook salmon data, respectively. Self-assignment accuracy ≥90% was obtained with panels of 670 and 384 SNPs for each data set, respectively, a level of accuracy never reached for these species using F ST -selected panels. Our results demonstrate a role for machine-learning approaches in marker selection across large genomic data sets to improve assignment for management and conservation of exploited populations.

The representation of patriach perception in selected African literary ...

African Journals Online (AJOL)

This paperinterrogates the institutions of polygamy and polygyny as cultural artefacts that inform patrilineal and patriarchal beliefs; as well as nostalgic practices that impact negatively on African women's identities. The paper advocates the portrayal of women characters positively in African literature, instead of the prevalent ...

Interference-aware random beam selection for spectrum sharing systems

KAUST Repository

Abdallah, Mohamed M.

2012-09-01

Spectrum sharing systems have been introduced to alleviate the problem of spectrum scarcity by allowing secondary unlicensed networks to share the spectrum with primary licensed networks under acceptable interference levels to the primary users. In this paper, we develop interference-aware random beam selection schemes that provide enhanced throughput for the secondary link under the condition that the interference observed at the primary link is within a predetermined acceptable value. For a secondary transmitter equipped with multiple antennas, our schemes select a random beam, among a set of power- optimized orthogonal random beams, that maximizes the capacity of the secondary link while satisfying the interference constraint at the primary receiver for different levels of feedback information describing the interference level at the primary receiver. For the proposed schemes, we develop a statistical analysis for the signal-to-noise and interference ratio (SINR) statistics as well as the capacity of the secondary link. Finally, we present numerical results that study the effect of system parameters including number of beams and the maximum transmission power on the capacity of the secondary link attained using the proposed schemes. © 2012 IEEE.

Interference-aware random beam selection for spectrum sharing systems

KAUST Repository

Abdallah, Mohamed M.; Sayed, Mostafa M.; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

2012-01-01

. In this paper, we develop interference-aware random beam selection schemes that provide enhanced throughput for the secondary link under the condition that the interference observed at the primary link is within a predetermined acceptable value. For a secondary

African Traditional Religion and the African Cinema: The Case of Nollywood

OpenAIRE

Akua Agyeiwaa Manieson

2014-01-01

This study aims at a discussion of the portrayal of African Traditional Religion in some selected Nollywood films. It is herein argued that Nollywood is deliberately bent on denigrating the African traditional religion. Three main religious groups are represented in Nigeria. These are Muslims forming about 50.4%, followed by Christians 48.2% while followers of other religions especially African Traditional religion, comprises 1.4% 1. This statistic has earned for Nigeria an accolade: a multi-...

The signature of positive selection at randomly chosen loci.

OpenAIRE

Przeworski, Molly

2002-01-01

In Drosophila and humans, there are accumulating examples of loci with a significant excess of high-frequency-derived alleles or high levels of linkage disequilibrium, relative to a neutral model of a random-mating population of constant size. These are features expected after a recent selective sweep. Their prevalence suggests that positive directional selection may be widespread in both species. However, as I show here, these features do not persist long after the sweep ends: The high-frequ...

Simulated Performance Evaluation of a Selective Tracker Through Random Scenario Generation

DEFF Research Database (Denmark)

Hussain, Dil Muhammad Akbar

2006-01-01

performance assessment. Therefore, a random target motion scenario is adopted. Its implementation in particular for testing the proposed selective track splitting algorithm using Kalman filters is investigated through a number of performance parameters which gives the activity profile of the tracking scenario......  The paper presents a simulation study on the performance of a target tracker using selective track splitting filter algorithm through a random scenario implemented on a digital signal processor.  In a typical track splitting filter all the observation which fall inside a likelihood ellipse...... are used for update, however, in our proposed selective track splitting filter less number of observations are used for track update.  Much of the previous performance work [1] has been done on specific (deterministic) scenarios. One of the reasons for considering the specific scenarios, which were...

Minimization over randomly selected lines

Directory of Open Access Journals (Sweden)

Ismet Sahin

2013-07-01

Full Text Available This paper presents a population-based evolutionary optimization method for minimizing a given cost function. The mutation operator of this method selects randomly oriented lines in the cost function domain, constructs quadratic functions interpolating the cost function at three different points over each line, and uses extrema of the quadratics as mutated points. The crossover operator modifies each mutated point based on components of two points in population, instead of one point as is usually performed in other evolutionary algorithms. The stopping criterion of this method depends on the number of almost degenerate quadratics. We demonstrate that the proposed method with these mutation and crossover operations achieves faster and more robust convergence than the well-known Differential Evolution and Particle Swarm algorithms.

Intramuscular Artesunate for Severe Malaria in African Children: A Multicenter Randomized Controlled Trial.

Directory of Open Access Journals (Sweden)

Peter G Kremsner

2016-01-01

Full Text Available Current artesunate (ARS regimens for severe malaria are complex. Once daily intramuscular (i.m. injection for 3 d would be simpler and more appropriate for remote health facilities than the current WHO-recommended regimen of five intravenous (i.v. or i.m. injections over 4 d. We compared both a three-dose i.m. and a three-dose i.v. parenteral ARS regimen with the standard five-dose regimen using a non-inferiority design (with non-inferiority margins of 10%.This randomized controlled trial included children (0.5-10 y with severe malaria at seven sites in five African countries to assess whether the efficacy of simplified three-dose regimens is non-inferior to a five-dose regimen. We randomly allocated 1,047 children to receive a total dose of 12 mg/kg ARS as either a control regimen of five i.m. injections of 2.4 mg/kg (at 0, 12, 24, 48, and 72 h (n = 348 or three injections of 4 mg/kg (at 0, 24, and 48 h either i.m. (n = 348 or i.v. (n = 351, both of which were the intervention arms. The primary endpoint was the proportion of children with ≥ 99% reduction in parasitemia at 24 h from admission values, measured by microscopists who were blinded to the group allocations. Primary analysis was performed on the per-protocol population, which was 96% of the intention-to-treat population. Secondary analyses included an analysis of host and parasite genotypes as risks for prolongation of parasite clearance kinetics, measured every 6 h, and a Kaplan-Meier analysis to compare parasite clearance kinetics between treatment groups. A post hoc analysis was performed for delayed anemia, defined as hemoglobin ≤ 7 g/dl 7 d or more after admission. The per-protocol population was 1,002 children (five-dose i.m.: n = 331; three-dose i.m.: n = 338; three-dose i.v.: n = 333; 139 participants were lost to follow-up. In the three-dose i.m. arm, 265/338 (78% children had a ≥ 99% reduction in parasitemia at 24 h compared to 263/331 (79% receiving the five-dose i

Performance of Africanized honeybee colonies settled by queens selected for different traits

Directory of Open Access Journals (Sweden)

Tânia Patrícia Schafaschek

2016-01-01

Full Text Available We evaluated varroa infestation and the performance of Africanized honeybee colonies with queens selected for honey and royal jelly production, and also unselected queens, correlating with climatic variables. In Campo Alegre, Santa Catarina State, Brazil, the experiment I used 10 Langstroth hives and in Mafra, Santa Catarina State, Brazil, the experiment II was performed with 15 Schenk hives. A mapping in areas of sealed and unsealed brood, honey and pollen was carried out on days zero, 45 and 90 days after the introduction of the queen. In the experiment I, there was interaction between the type of queen selection and the evaluation period for areas of sealed brood, honey, and total stored food. The group selected for royal jelly production presented larger sealed brood area and smaller honey area at 90 days. Varroa infestation was lower (p < 0.05 at 90 days. The type of queen selection and the evaluation period influenced the sealed brood area, the total brood and the total area occupied in the colony. The high relative humidity caused greater honey storage for the local group. The different groups of queens presented different behavior according to the environment in which they are settled.

Selection for altruism through random drift in variable size populations

Directory of Open Access Journals (Sweden)

Houchmandzadeh Bahram

2012-05-01

Full Text Available Abstract Background Altruistic behavior is defined as helping others at a cost to oneself and a lowered fitness. The lower fitness implies that altruists should be selected against, which is in contradiction with their widespread presence is nature. Present models of selection for altruism (kin or multilevel show that altruistic behaviors can have ‘hidden’ advantages if the ‘common good’ produced by altruists is restricted to some related or unrelated groups. These models are mostly deterministic, or assume a frequency dependent fitness. Results Evolutionary dynamics is a competition between deterministic selection pressure and stochastic events due to random sampling from one generation to the next. We show here that an altruistic allele extending the carrying capacity of the habitat can win by increasing the random drift of “selfish” alleles. In other terms, the fixation probability of altruistic genes can be higher than those of a selfish ones, even though altruists have a smaller fitness. Moreover when populations are geographically structured, the altruists advantage can be highly amplified and the fixation probability of selfish genes can tend toward zero. The above results are obtained both by numerical and analytical calculations. Analytical results are obtained in the limit of large populations. Conclusions The theory we present does not involve kin or multilevel selection, but is based on the existence of random drift in variable size populations. The model is a generalization of the original Fisher-Wright and Moran models where the carrying capacity depends on the number of altruists.

Selection bias and subject refusal in a cluster-randomized controlled trial

Directory of Open Access Journals (Sweden)

Rochelle Yang

2017-07-01

Full Text Available Abstract Background Selection bias and non-participation bias are major methodological concerns which impact external validity. Cluster-randomized controlled trials are especially prone to selection bias as it is impractical to blind clusters to their allocation into intervention or control. This study assessed the impact of selection bias in a large cluster-randomized controlled trial. Methods The Improved Cardiovascular Risk Reduction to Enhance Rural Primary Care (ICARE study examined the impact of a remote pharmacist-led intervention in twelve medical offices. To assess eligibility, a standardized form containing patient demographics and medical information was completed for each screened patient. Eligible patients were approached by the study coordinator for recruitment. Both the study coordinator and the patient were aware of the site’s allocation prior to consent. Patients who consented or declined to participate were compared across control and intervention arms for differing characteristics. Statistical significance was determined using a two-tailed, equal variance t-test and a chi-square test with adjusted Bonferroni p-values. Results were adjusted for random cluster variation. Results There were 2749 completed screening forms returned to research staff with 461 subjects who had either consented or declined participation. Patients with poorly controlled diabetes were found to be significantly more likely to decline participation in intervention sites compared to those in control sites. A higher mean diastolic blood pressure was seen in patients with uncontrolled hypertension who declined in the control sites compared to those who declined in the intervention sites. However, these findings were no longer significant after adjustment for random variation among the sites. After this adjustment, females were now found to be significantly more likely to consent than males (odds ratio = 1.41; 95% confidence interval = 1.03, 1

Efficacy and Mediation of a Theory-Based Physical Activity Intervention for African American Men Who Have Sex with Men: A Randomized Controlled Trial.

Science.gov (United States)

Zhang, Jingwen; Jemmott, John B; O'Leary, Ann; Stevens, Robin; Jemmott, Loretta Sweet; Icard, Larry D; Hsu, Janet; Rutledge, Scott E

2017-02-01

Few trials have tested physical-activity interventions among sexual minorities, including African American men who have sex with men (MSM). We examined the efficacy and mediation of the Being Responsible for Ourselves (BRO) physical-activity intervention among African American MSM. African American MSM were randomized to the physical-activity intervention consisting of three 90-min one-on-one sessions or an attention-matched control intervention and completed pre-intervention, immediately post-intervention, and 6- and 12-month post-intervention audio computer-based surveys. Of the 595 participants, 503 completed the 12-month follow-up. Generalized estimating equation models revealed that the intervention increased self-reported physical activity compared with the control intervention, adjusted for pre-intervention physical activity. Mediation analyses suggested that the intervention increased reasoned action approach variables, subjective norm and self-efficacy, increasing intention immediately post-intervention, which increased physical activity during the follow-up period. Interventions targeting reasoned action approach variables may contribute to efforts to increase African American MSM's physical activity. The trial was registered with the ClinicalTrials.gov Identifier NCT02561286 .

Development of admixture mapping panels for African Americans from commercial high-density SNP arrays

Directory of Open Access Journals (Sweden)

Dunston Georgia M

2010-07-01

Full Text Available Abstract Background Admixture mapping is a powerful approach for identifying genetic variants involved in human disease that exploits the unique genomic structure in recently admixed populations. To use existing published panels of ancestry-informative markers (AIMs for admixture mapping, markers have to be genotyped de novo for each admixed study sample and samples representing the ancestral parental populations. The increased availability of dense marker data on commercial chips has made it feasible to develop panels wherein the markers need not be predetermined. Results We developed two panels of AIMs (~2,000 markers each based on the Affymetrix Genome-Wide Human SNP Array 6.0 for admixture mapping with African American samples. These two AIM panels had good map power that was higher than that of a denser panel of ~20,000 random markers as well as other published panels of AIMs. As a test case, we applied the panels in an admixture mapping study of hypertension in African Americans in the Washington, D.C. metropolitan area. Conclusions Developing marker panels for admixture mapping from existing genome-wide genotype data offers two major advantages: (1 no de novo genotyping needs to be done, thereby saving costs, and (2 markers can be filtered for various quality measures and replacement markers (to minimize gaps can be selected at no additional cost. Panels of carefully selected AIMs have two major advantages over panels of random markers: (1 the map power from sparser panels of AIMs is higher than that of ~10-fold denser panels of random markers, and (2 clusters can be labeled based on information from the parental populations. With current technology, chip-based genome-wide genotyping is less expensive than genotyping ~20,000 random markers. The major advantage of using random markers is the absence of ascertainment effects resulting from the process of selecting markers. The ability to develop marker panels informative for ancestry from

Interference-aware random beam selection schemes for spectrum sharing systems

KAUST Repository

Abdallah, Mohamed; Qaraqe, Khalid; Alouini, Mohamed-Slim

2012-01-01

users. In this work, we develop interference-aware random beam selection schemes that provide enhanced performance for the secondary network under the condition that the interference observed by the receivers of the primary network is below a

FAVAR Analysis of Foreign Investment with Capital Market Predictors: Evidence on Nigerian and Selected African Stock Exchanges

Directory of Open Access Journals (Sweden)

David Umoru

2018-03-01

Full Text Available Econometrically, we analyzed role of selected African stock exchanges in welcoming FDI inflows by estimating time-varying factor augmented vector auto-regression (FAVAR model for 2006:Q1 to 2017:Q4. Our results support FDI being massively influenced by movements in two stock market predictors namely, stock market's size, that is, total market value of stock market's listed shares calculated by multiplying a stock market’s shares listed by current market price of one share and stock market liquidity which is total value of traded shares relative to the size of the economy. By empirical inference, African stock exchanges exhibit inordinate turnover ratio and so these markets are exceedingly liquid. Particularly, transactions at stock exchange are significant indicators for foreign investors and total market value of listed shares in stock markets is linked positively with FDI inflow into Africa. The empirical finding is that viable African stock exchanges are attractive indicator of market concentration and high investment profile in Africa. The study so remarked the requisite to advance the stock exchange in order to boost funds accumulation for investment drive. Also, African governments should project and implement stock market-friendly procedures acceptable to maximize welfares of spillover effects of FDI.

Haematological and serum biochemical parameters of West African ...

African Journals Online (AJOL)

The study was conducted to evaluate the haematological and serum biochemical parameters of West African dwarf goats fed ensiled cassava leaves with molasses and caged layer waste. Eighteen West African dwarf goats were randomly assigned to three experimental diets consisting of cassava leaves ensiled alone ...

Vitamin D status of older South Africans | Charlton | South African ...

African Journals Online (AJOL)

Objective: To detennine the vitamin D status of older 'coloured' South Africans who had not sustained a fracture. Design: Cross-sectional analytic study. Methods: A random sample of 200 non-institutionalised subjects in Cape Town aged ≥65 years was drawn using a two-stage cluster design. Trained fieldworkers ...

Continuous-Time Mean-Variance Portfolio Selection with Random Horizon

International Nuclear Information System (INIS)

Yu, Zhiyong

2013-01-01

This paper examines the continuous-time mean-variance optimal portfolio selection problem with random market parameters and random time horizon. Treating this problem as a linearly constrained stochastic linear-quadratic optimal control problem, I explicitly derive the efficient portfolios and efficient frontier in closed forms based on the solutions of two backward stochastic differential equations. Some related issues such as a minimum variance portfolio and a mutual fund theorem are also addressed. All the results are markedly different from those in the problem with deterministic exit time. A key part of my analysis involves proving the global solvability of a stochastic Riccati equation, which is interesting in its own right

Continuous-Time Mean-Variance Portfolio Selection with Random Horizon

Energy Technology Data Exchange (ETDEWEB)

Yu, Zhiyong, E-mail: yuzhiyong@sdu.edu.cn [Shandong University, School of Mathematics (China)

2013-12-15

This paper examines the continuous-time mean-variance optimal portfolio selection problem with random market parameters and random time horizon. Treating this problem as a linearly constrained stochastic linear-quadratic optimal control problem, I explicitly derive the efficient portfolios and efficient frontier in closed forms based on the solutions of two backward stochastic differential equations. Some related issues such as a minimum variance portfolio and a mutual fund theorem are also addressed. All the results are markedly different from those in the problem with deterministic exit time. A key part of my analysis involves proving the global solvability of a stochastic Riccati equation, which is interesting in its own right.

A Pilot Trial Examining African American and White Responses to Algorithm-Guided Smoking Cessation Medication Selection in Persons Living with HIV.

Science.gov (United States)

Valera, Pamela; McClernon, F Joseph; Burkholder, Greer; Mugavero, Michael J; Willig, James; O'Cleirigh, Conall; Cropsey, Karen L

2017-07-01

Algorithm-based treatments (AT) may be an effective clinical tool to aid HIV clinicians in prescribing pharmacotherapy to increase smoking cessation among people living with HIV (PLWH). Initial results from AT indicated significant increases in abstinence self-efficacy and medication utilization and declines in cigarettes smoked per day across time. Given historical racial disparities, it is unclear if both African Americans and White smokers would benefit equally from this type of intervention. Thus, the aim of this study was to examine racial differences in response to AT guided smoking cessation for African American and White smokers living with HIV. One hundred PLWH smokers (n = 100) were randomized to receive either AT guided smoking cessation or Treatment as Usual (TAU) which consisted of instructing participants to talk to a provider about smoking cessation assistance when ready to make a quit attempt. Participants were African American (75%) and White (25%) and majority men (71%) who had never been married (56%). African Americans smoked fewer cigarettes and were more likely to smoke mentholated cigarettes compared to White smokers at baseline. African Americans increased their use of other tobacco products (cigars/cigarillos) over time relative to White smokers. A significant interaction between race and quit goal was observed, with White smokers who reported complete abstinence as their goal having higher quit rates, while African Americans who reported a goal other than complete abstinence demonstrating higher quit rates. The increased use of cigars/cigarillos during quit attempts as well as having a goal other than complete abstinence should be considered when applying algorithm based interventions for PLWH African American smokers.

TEHRAN AIR POLLUTANTS PREDICTION BASED ON RANDOM FOREST FEATURE SELECTION METHOD

Directory of Open Access Journals (Sweden)

A. Shamsoddini

2017-09-01

Full Text Available Air pollution as one of the most serious forms of environmental pollutions poses huge threat to human life. Air pollution leads to environmental instability, and has harmful and undesirable effects on the environment. Modern prediction methods of the pollutant concentration are able to improve decision making and provide appropriate solutions. This study examines the performance of the Random Forest feature selection in combination with multiple-linear regression and Multilayer Perceptron Artificial Neural Networks methods, in order to achieve an efficient model to estimate carbon monoxide and nitrogen dioxide, sulfur dioxide and PM2.5 contents in the air. The results indicated that Artificial Neural Networks fed by the attributes selected by Random Forest feature selection method performed more accurate than other models for the modeling of all pollutants. The estimation accuracy of sulfur dioxide emissions was lower than the other air contaminants whereas the nitrogen dioxide was predicted more accurate than the other pollutants.

Tehran Air Pollutants Prediction Based on Random Forest Feature Selection Method

Science.gov (United States)

Shamsoddini, A.; Aboodi, M. R.; Karami, J.

2017-09-01

Air pollution as one of the most serious forms of environmental pollutions poses huge threat to human life. Air pollution leads to environmental instability, and has harmful and undesirable effects on the environment. Modern prediction methods of the pollutant concentration are able to improve decision making and provide appropriate solutions. This study examines the performance of the Random Forest feature selection in combination with multiple-linear regression and Multilayer Perceptron Artificial Neural Networks methods, in order to achieve an efficient model to estimate carbon monoxide and nitrogen dioxide, sulfur dioxide and PM2.5 contents in the air. The results indicated that Artificial Neural Networks fed by the attributes selected by Random Forest feature selection method performed more accurate than other models for the modeling of all pollutants. The estimation accuracy of sulfur dioxide emissions was lower than the other air contaminants whereas the nitrogen dioxide was predicted more accurate than the other pollutants.

Population Genomics of sub-saharan Drosophila melanogaster: African diversity and non-African admixture.

Directory of Open Access Journals (Sweden)

John E Pool

Full Text Available Drosophila melanogaster has played a pivotal role in the development of modern population genetics. However, many basic questions regarding the demographic and adaptive history of this species remain unresolved. We report the genome sequencing of 139 wild-derived strains of D. melanogaster, representing 22 population samples from the sub-Saharan ancestral range of this species, along with one European population. Most genomes were sequenced above 25X depth from haploid embryos. Results indicated a pervasive influence of non-African admixture in many African populations, motivating the development and application of a novel admixture detection method. Admixture proportions varied among populations, with greater admixture in urban locations. Admixture levels also varied across the genome, with localized peaks and valleys suggestive of a non-neutral introgression process. Genomes from the same location differed starkly in ancestry, suggesting that isolation mechanisms may exist within African populations. After removing putatively admixed genomic segments, the greatest genetic diversity was observed in southern Africa (e.g. Zambia, while diversity in other populations was largely consistent with a geographic expansion from this potentially ancestral region. The European population showed different levels of diversity reduction on each chromosome arm, and some African populations displayed chromosome arm-specific diversity reductions. Inversions in the European sample were associated with strong elevations in diversity across chromosome arms. Genomic scans were conducted to identify loci that may represent targets of positive selection within an African population, between African populations, and between European and African populations. A disproportionate number of candidate selective sweep regions were located near genes with varied roles in gene regulation. Outliers for Europe-Africa F(ST were found to be enriched in genomic regions of locally

Population Genomics of Sub-Saharan Drosophila melanogaster: African Diversity and Non-African Admixture

Science.gov (United States)

Pool, John E.; Corbett-Detig, Russell B.; Sugino, Ryuichi P.; Stevens, Kristian A.; Cardeno, Charis M.; Crepeau, Marc W.; Duchen, Pablo; Emerson, J. J.; Saelao, Perot; Begun, David J.; Langley, Charles H.

2012-01-01

Drosophila melanogaster has played a pivotal role in the development of modern population genetics. However, many basic questions regarding the demographic and adaptive history of this species remain unresolved. We report the genome sequencing of 139 wild-derived strains of D. melanogaster, representing 22 population samples from the sub-Saharan ancestral range of this species, along with one European population. Most genomes were sequenced above 25X depth from haploid embryos. Results indicated a pervasive influence of non-African admixture in many African populations, motivating the development and application of a novel admixture detection method. Admixture proportions varied among populations, with greater admixture in urban locations. Admixture levels also varied across the genome, with localized peaks and valleys suggestive of a non-neutral introgression process. Genomes from the same location differed starkly in ancestry, suggesting that isolation mechanisms may exist within African populations. After removing putatively admixed genomic segments, the greatest genetic diversity was observed in southern Africa (e.g. Zambia), while diversity in other populations was largely consistent with a geographic expansion from this potentially ancestral region. The European population showed different levels of diversity reduction on each chromosome arm, and some African populations displayed chromosome arm-specific diversity reductions. Inversions in the European sample were associated with strong elevations in diversity across chromosome arms. Genomic scans were conducted to identify loci that may represent targets of positive selection within an African population, between African populations, and between European and African populations. A disproportionate number of candidate selective sweep regions were located near genes with varied roles in gene regulation. Outliers for Europe-Africa FST were found to be enriched in genomic regions of locally elevated cosmopolitan

Effect of Behavioral Intervention on Dilated Fundus Examination Rates in Older African American Individuals With Diabetes Mellitus: A Randomized Clinical Trial.

Science.gov (United States)

Weiss, David M; Casten, Robin J; Leiby, Benjamin E; Hark, Lisa A; Murchison, Ann P; Johnson, Deiana; Stratford, Shayla; Henderer, Jeffrey; Rovner, Barry W; Haller, Julia A

2015-09-01

African American individuals are at high risk of diabetes mellitus and diabetic retinopathy but have suboptimal rates of dilated fundus examinations (DFEs). Early intervention is crucial for the prevention of diabetic retinopathy in this high-risk population. To test the efficacy of behavioral activation for diabetic retinopathy prevention on rates of DFEs in older African American individuals with diabetes mellitus. Masked randomized clinical trial at 2 urban medical centers from October 1, 2010, to May 31, 2014. Participants included 206 African American individuals 65 years and older with diabetes mellitus who had not obtained a DFE in the preceding 12 months. Participants were randomized to either behavioral activation for diabetic retinopathy prevention, a behavioral intervention designed to provide education, facilitate identifying and addressing health care barriers, and promote goal setting to improve rates of DFEs, or supportive therapy, a control condition. The primary outcome was medical documentation of a DFE at 6 months' follow-up. Secondary outcomes included the Risk Perceptions and Risk Knowledge Survey of Diabetes Mellitus, Diabetes Self-Care Inventory, Patient Health Questionnaire 9, and National Eye Institute Vision Function Questionnaire 25 scores and hemoglobin A1c levels. More participants in the behavioral activation for diabetic retinopathy prevention group (87.9%) obtained a DFE compared with those in the supportive therapy group (34.1%) by the 6-month follow-up assessment (P diabetic retinopathy prevention group were 2.5 times more likely to obtain a DFE compared with those in the supportive therapy group (risk ratio = 2.58; 95% CI, 1.91-3.48; P Knowledge Survey of Diabetes Mellitus or National Eye Institute Vision Function Questionnaire 25 composite scores; however, both groups had improved adherence to diabetes mellitus self-care behaviors from baseline to 6-month follow-up. Behavioral activation for diabetic retinopathy

Hebbian Learning in a Random Network Captures Selectivity Properties of the Prefrontal Cortex

Science.gov (United States)

Lindsay, Grace W.

2017-01-01

Complex cognitive behaviors, such as context-switching and rule-following, are thought to be supported by the prefrontal cortex (PFC). Neural activity in the PFC must thus be specialized to specific tasks while retaining flexibility. Nonlinear “mixed” selectivity is an important neurophysiological trait for enabling complex and context-dependent behaviors. Here we investigate (1) the extent to which the PFC exhibits computationally relevant properties, such as mixed selectivity, and (2) how such properties could arise via circuit mechanisms. We show that PFC cells recorded from male and female rhesus macaques during a complex task show a moderate level of specialization and structure that is not replicated by a model wherein cells receive random feedforward inputs. While random connectivity can be effective at generating mixed selectivity, the data show significantly more mixed selectivity than predicted by a model with otherwise matched parameters. A simple Hebbian learning rule applied to the random connectivity, however, increases mixed selectivity and enables the model to match the data more accurately. To explain how learning achieves this, we provide analysis along with a clear geometric interpretation of the impact of learning on selectivity. After learning, the model also matches the data on measures of noise, response density, clustering, and the distribution of selectivities. Of two styles of Hebbian learning tested, the simpler and more biologically plausible option better matches the data. These modeling results provide clues about how neural properties important for cognition can arise in a circuit and make clear experimental predictions regarding how various measures of selectivity would evolve during animal training. SIGNIFICANCE STATEMENT The prefrontal cortex is a brain region believed to support the ability of animals to engage in complex behavior. How neurons in this area respond to stimuli—and in particular, to combinations of stimuli (�

Performance Evaluation of User Selection Protocols in Random Networks with Energy Harvesting and Hardware Impairments

Directory of Open Access Journals (Sweden)

Tan Nhat Nguyen

2016-01-01

Full Text Available In this paper, we evaluate performances of various user selection protocols under impact of hardware impairments. In the considered protocols, a Base Station (BS selects one of available Users (US to serve, while the remaining USs harvest the energy from the Radio Frequency (RF transmitted by the BS. We assume that all of the US randomly appear around the BS. In the Random Selection Protocol (RAN, the BS randomly selects a US to transmit the data. In the second proposed protocol, named Minimum Distance Protocol (MIND, the US that is nearest to the BS will be chosen. In the Optimal Selection Protocol (OPT, the US providing the highest channel gain between itself and the BS will be served. For performance evaluation, we derive exact and asymptotic closed-form expressions of average Outage Probability (OP over Rayleigh fading channels. We also consider average harvested energy per a US. Finally, Monte-Carlo simulations are then performed to verify the theoretical results.

Do birds of a feather flock together? The variable bases for African American, Asian American, and European American adolescents' selection of similar friends.

Science.gov (United States)

Hamm, J V

2000-03-01

Variability in adolescent-friend similarity is documented in a diverse sample of African American, Asian American, and European American adolescents. Similarity was greatest for substance use, modest for academic orientations, and low for ethnic identity. Compared with Asian American and European American adolescents, African American adolescents chose friends who were less similar with respect to academic orientation or substance use but more similar with respect to ethnic identity. For all three ethnic groups, personal endorsement of the dimension in question and selection of cross-ethnic-group friends heightened similarity. Similarity was a relative rather than an absolute selection criterion: Adolescents did not choose friends with identical orientations. These findings call for a comprehensive theory of friendship selection sensitive to diversity in adolescents' experiences. Implications for peer influence and self-development are discussed.

Gender Factors Associated with Sexual Abstinent Behaviour of Rural South African High School Going Youth in KwaZulu-Natal, South Africa

Science.gov (United States)

Dlamini, Siyabonga; Taylor, Myra; Mkhize, Nosipho; Huver, Rosemarie; Sathiparsad, Reshma; de Vries, Hein; Naidoo, Kala; Jinabhai, Champak

2009-01-01

The cross-sectional study investigated South African rural high school learners' choice of sexual abstinence in order to be able to develop tailored health education messages. All Grade 9 learners from one class at each of 10 randomly selected rural high schools participated. The Integrated Model for Motivational and Behavioural Change was used to…

Randomized Controlled Trials of Technology-Based HIV/STI and Drug Abuse Preventive Interventions for African American and Hispanic Youth: Systematic Review.

Science.gov (United States)

Córdova, David; Mendoza Lua, Frania; Ovadje, Lauretta; Hong, Ethan; Castillo, Berenice; Salas-Wright, Christopher P

2017-12-13

HIV/sexually transmitted infections (STIs) and drug abuse remain significant public health concerns in the United States, and African American and Hispanic youth are disproportionately affected. Although technology-based interventions are efficacious in preventing and reducing HIV/STI and licit/illicit drug use behaviors, relatively little is known regarding the state of the science of these interventions among African American and Hispanic youth. The aim of this review is to identify and examine randomized controlled trials (RCTs) of technology-based HIV/STI and/or drug abuse preventive interventions for African American and Hispanic youth. We searched electronic databases (ie, PubMed, Proquest, PsycINFO, Ebscohost, Google Scholar) to identify studies between January 2006 and October 2016. RCTs of technology-based interventions targeting African American and Hispanic youth HIV/STI risk behaviors, including sexual risk, licit and illicit drug use, and HIV/STI testing were included. Our search revealed a total of three studies that used an RCT design and included samples comprised of >50% African American and/or Hispanic youth. The follow-up assessments ranged from two weeks to six months and the number of participants in each trial ranged from 72 to 141. The three interventions were theory-driven, interactive, and tailored. The long-term effects of the interventions were mixed, and outcomes included reductions in sex partners, licit drug use, and condomless anal sex acts. Although technology-based interventions seem promising in the prevention of HIV/STI and drug abuse among African American and Hispanic youth, more research is needed. ©David Córdova, Frania Mendoza Lua, Lauretta Ovadje, Ethan Hong, Berenice Castillo, Christopher P Salas-Wright. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 13.12.2017.

Effects of exercise on l-carnitine and lipid metabolism in African catfish (Clarias gariepinus) fed different dietary l-carnitine and lipid levels

NARCIS (Netherlands)

Ozorio, R.O.A.; Ginneken, van V.J.T.; Bessa, R.J.B.; Verstegen, M.W.A.; Verreth, J.A.J.; Huisman, E.A.

2010-01-01

African catfish (Clarias gariepinus) were fed four isonitrogenous diets (34 % crude protein), each containing one of two lipid (100 or 180 g/kg) and two l-carnitine (15 or 1000 mg/kg) levels. After 81 d of feeding, thirty-two fish (body weight 32 g) from each dietary group were randomly selected,

Mainstreaming biodiversity and wildlife management into climate change policy frameworks in selected east and southern African countries

Directory of Open Access Journals (Sweden)

Olga L. Kupika

2016-04-01

Full Text Available The Rio+20 outcomes document, the Future We Want, enshrines green economy as one of the platforms to attain sustainable development and calls for measures that seek to address climate change and biodiversity management. This paper audits climate change policies from selected east and southern African countries to determine the extent to which climate change legislation mainstreams biodiversity and wildlife management. A scan of international, continental, regional and national climate change policies was conducted to assess whether they include biodiversity and/or wildlife management issues. The key finding is that many climate change policy–related documents, particularly the National Adaptation Programme of Actions (NAPAs, address threats to biodiversity and wildlife resources. However, international policies like the United Nations Framework Convention on Climate Change and Kyoto Protocol do not address the matter under deliberation. Regional climate change policies such as the East African Community, Common Market for Eastern and Southern Africa and African Union address biodiversity and/or wildlife issues whilst the Southern African Development Community region does not have a stand-alone policy for climate change. Progressive countries like Rwanda, Uganda, Tanzania and Zambia have recently put in place detailed NAPAs which are mainstream responsive strategies intended to address climate change adaptation in the wildlife sector. Keywords: mainstreaming, biodiversity, wildlife, climate change policy, east and southern Africa

Brief Computer-Delivered Intervention to Increase Parental Monitoring in Families of African American Adolescents with Type 1 Diabetes: A Randomized Controlled Trial.

Science.gov (United States)

Ellis, Deborah A; Idalski Carcone, April; Ondersma, Steven J; Naar-King, Sylvie; Dekelbab, Bassem; Moltz, Kathleen

2017-06-01

African American adolescents with type 1 diabetes (T1D) are at elevated risk for poor diabetes management and metabolic control. Parental supervision and monitoring of adolescent diabetes management have been shown to promote better diabetes management among adolescents, but parents typically decrease their oversight during the transition to independent diabetes care. The purpose of the study was to conduct a randomized clinical trial to test the feasibility and efficacy of a three-session, computer-delivered motivational intervention (The 3Ms) to promote increased parental monitoring among primary caregivers of young African American adolescents with T1D. The intervention was brief and optimized for delivery during routine diabetes clinic visits. Sixty-seven adolescents with T1D aged 11-14 and their primary caregiver were randomly assigned to one of three arms: adolescent and parent motivational intervention (Arm 1), adolescent control and parent motivational intervention (Arm 2), or adolescent and parent control (Arm 3). Intervention effects were assessed 1 month after intervention completion. Parents in Arm 1 and Arm 2 had significant increases in knowledge of the importance of monitoring adolescents' diabetes care. Parents in Arm 2 also had trend to significant increases in direct observation and monitoring of adolescent diabetes care, and adolescents in Arm 2 had significant improvements in glycemic control. Findings from the present study provide preliminary support for the efficacy of a brief, computer-delivered parenting intervention for improving family management practices and adolescent health outcomes among African American adolescents with T1D and their caregivers.

South African consumers’ opinions and beliefs regarding the health benefits of soy and soy products

OpenAIRE

Bosman, Magdalena J.C.; Ellis, Susanna M.; Jerling, Johann C.; Badham, Jane; Van der Merwe, Daleen

2011-01-01

Studies linking diet and health and consumers’ demand for health information, has led to an increasing awareness of the role of nutrition in health and disease. Interest in soy foods and an awareness of its health benefits has also increased. The objective was to assess South African (SA) consumers’ opinions and beliefs regarding the health benefits of soy and soy products using different statements. This cross-sectional study randomly selected 3001 respondents from metropolita...

The reliability of randomly selected final year pharmacy students in ...

African Journals Online (AJOL)

Employing ANOVA, factorial experimental analysis, and the theory of error, reliability studies were conducted on the assessment of the drug product chloroquine phosphate tablets. The G–Study employed equal numbers of the factors for uniform control, and involved three analysts (randomly selected final year Pharmacy ...

Evaluating research recruitment strategies to improve response rates amongst South African nurses

Directory of Open Access Journals (Sweden)

Natasha Khamisa

2014-03-01

Research purpose: The aim of this study was to evaluate three research recruitment methods for their impact on recruitment and participation rates amongst South African nurses. Motivation for the study: A limited number of studies exist that formally evaluates different recruitment strategies to improve participation in research amongst nurses within developing contexts, especially South Africa. Research approach, design and method: Participants were recruited using three different methods. Of the 250 nurses randomly selected and invited to participate in a cross-sectional survey, 201 agreed and 162 (81% returned the questionnaires. Main findings: Nursing management participation in the recruitment and data collection process produces more favourable response rates. Reminders and the use of shorter questionnaires also aid higher response rates. Practical/managerial implications: Reminders as well as face-to-face recruitment strategies (especially by a familiar person successfully improved participation rates amongst South African nurses in this study. Contribution/value-add: This study identifies some strategies that could be used more widely to increase the recruitment and participation of South African nurses in research whilst potentially improving their work situation.

Simple CPR: A randomized, controlled trial of video self-instructional cardiopulmonary resuscitation training in an African American church congregation.

Science.gov (United States)

Todd, K H; Heron, S L; Thompson, M; Dennis, R; O'Connor, J; Kellermann, A L

1999-12-01

Despite the proven efficacy of cardiopulmonary resuscitation (CPR), only a small fraction of the population knows how to perform it. As a result, rates of bystander CPR and rates of survival from cardiac arrest are low. Bystander CPR is particularly uncommon in the African American community. Successful development of a simplified approach to CPR training could boost rates of bystander CPR and save lives. We conducted the following randomized, controlled study to determine whether video self-instruction (VSI) in CPR results in comparable or better performance than traditional CPR training. This randomized, controlled trial was conducted among congregational volunteers in an African American church in Atlanta, GA. Subjects were randomly assigned to receive either 34 minutes of VSI or the 4-hour American Heart Association "Heartsaver" CPR course. Two months after training, blinded observers used explicit criteria to assess CPR performance in a simulated cardiac arrest setting. A recording manikin was used to measure ventilation and chest compression characteristics. Participants also completed a written test of CPR-related knowledge and attitudes. VSI trainees displayed a comparable level of performance to that achieved by traditional trainees. Observers scored 40% of VSI trainees competent or better in performing CPR, compared with only 16% of traditional trainees (absolute difference 24%, 95% confidence interval 8% to 40%). Data from the recording manikin confirmed these observations. VSI trainees and traditional trainees achieved comparable scores on tests of CPR-related knowledge and attitudes. Thirty-four minutes of VSI can produce CPR of comparable quality to that achieved by traditional training methods. VSI provides a simple, quick, consistent, and inexpensive alternative to traditional CPR instruction, and may be used to extend CPR training to historically underserved populations.

Random selection of items. Selection of n1 samples among N items composing a stratum

International Nuclear Information System (INIS)

Jaech, J.L.; Lemaire, R.J.

1987-02-01

STR-224 provides generalized procedures to determine required sample sizes, for instance in the course of a Physical Inventory Verification at Bulk Handling Facilities. The present report describes procedures to generate random numbers and select groups of items to be verified in a given stratum through each of the measurement methods involved in the verification. (author). 3 refs

Coping and work engagement in selected South African organisations

Directory of Open Access Journals (Sweden)

Sebastiaan Rothmann

2011-10-01

Research purpose: The objective of this study was to investigate the relationship between coping strategies and work engagement in three occupational groups in South Africa. Motivation for the study: There is little understanding of the relationship between effective forms of coping and positive outcomes (like work engagement. Research design, approach and method: The researchers used a survey design. They drew random and stratified samples (N = 3178 from three occupational groups. These were technical employees in an electricity provider, professional and enrolled nurses and police officers. They administered the Coping Orientations to the Problems Experienced (COPE and the Utrecht Work Engagement Scale (UWES. Main findings: The results showed that there was a statistically significant relationship between work engagement, problem-focused coping, positive reinterpretation and growth. In the nursing sample, high problem-focused coping, low avoidance and low ventilation of emotions predicted work engagement best. In the police sample, four coping strategies (problem-focused coping, seeking social support, turning to religion and low ventilation of emotions predicted work engagement best. In the technician sample, problem-focused coping and low ventilation of emotions predicted work engagement best. Practical/managerial implications: Organisations should consider employees’ coping strategies when they introduce interventions to improve work engagement. Contribution/value-add: This study contributes to the knowledge about the relationship between coping strategies and work engagement in South African organisations.

AFRICAN JOURNAL OF ECONOMIC REVIEW

African Journals Online (AJOL)

Dr Kazungu

African Journal of Economic Review, Volume IV, Issue 1, January 2016 ... infant mortality rates in 31 selected sub-Saharan African countries for the .... Also, declines in nutritional status as a result of upsurge in food prices may cause poor birth ..... Deaton, A. (1989) 'Rice Prices and Income Distribution in Thailand: A Non- ...

The mathematics of random mutation and natural selection for multiple simultaneous selection pressures and the evolution of antimicrobial drug resistance.

Science.gov (United States)

Kleinman, Alan

2016-12-20

The random mutation and natural selection phenomenon act in a mathematically predictable behavior, which when understood leads to approaches to reduce and prevent the failure of the use of these selection pressures when treating infections and cancers. The underlying principle to impair the random mutation and natural selection phenomenon is to use combination therapy, which forces the population to evolve to multiple selection pressures simultaneously that invoke the multiplication rule of probabilities simultaneously as well. Recently, it has been seen that combination therapy for the treatment of malaria has failed to prevent the emergence of drug-resistant variants. Using this empirical example and the principles of probability theory, the derivation of the equations describing this treatment failure is carried out. These equations give guidance as to how to use combination therapy for the treatment of cancers and infectious diseases and prevent the emergence of drug resistance. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Mechanisms of Vowel Variation in African American English.

Science.gov (United States)

Holt, Yolanda Feimster

2018-02-15

This research explored mechanisms of vowel variation in African American English by comparing 2 geographically distant groups of African American and White American English speakers for participation in the African American Shift and the Southern Vowel Shift. Thirty-two male (African American: n = 16, White American controls: n = 16) lifelong residents of cities in eastern and western North Carolina produced heed,hid,heyd,head,had,hod,hawed,whod,hood,hoed,hide,howed,hoyd, and heard 3 times each in random order. Formant frequency, duration, and acoustic analyses were completed for the vowels /i, ɪ, e, ɛ, æ, ɑ, ɔ, u, ʊ, o, aɪ, aʊ, oɪ, ɝ/ produced in the listed words. African American English speakers show vowel variation. In the west, the African American English speakers are participating in the Southern Vowel Shift and hod fronting of the African American Shift. In the east, neither the African American English speakers nor their White peers are participating in the Southern Vowel Shift. The African American English speakers show limited participation in the African American Shift. The results provide evidence of regional and socio-ethnic variation in African American English in North Carolina.

Entrepreneurial Intention: South African Youth’s Willingness to Start Tourism Businesses

Directory of Open Access Journals (Sweden)

Ikechukwu O. Ezeuduji

2017-10-01

Full Text Available Previous studies have recognised entrepreneurship as a tool capable of driving a nation’s economy. This study explored tourism entrepreneurial intention of South African youth, and analysed relationships between entrepreneurship statements on the one hand, and entrepreneurial intention and entrepreneurial impact on the other hand. A questionnaire survey was used to collect data from simple-randomly selected 220 youth living in Mtubatuba Local Municipality, KwaZulu-Natal Province of South Africa. Descriptive, bivariate and multivariate data analyses yield information to address research objectives. Significant proportion of the youth have entrepreneurial intention, these youth want to solve problems, are willing to pursuing their dreams, have internal locus of control, have positive outlook, have the ability to identify opportunities, and above all have strong sense of empathy. South African Department of Labour needs to develop an operational plan to provide business education, entrepreneurial skills, and relevant support that can empower the youth to start their own businesses. This study validates the alignment of entrepreneurship roles to those of making a difference, innovation, leadership, and self-belief; and shares a positive outlook for the South African economy if the enabling political and economic conditions are created.

African children's literature: a scholar's guide | Osaki | University of ...

African Journals Online (AJOL)

African children's books remain unparalleled in their ability to nurture the imagination and to provide relevant instruction and delight to the African child. Despite this truth, little research has been done on African literature, its nature, form and source of materials. This paper provides a selected check list of words by African ...

A Bayesian random effects discrete-choice model for resource selection: Population-level selection inference

Science.gov (United States)

Thomas, D.L.; Johnson, D.; Griffith, B.

2006-01-01

Modeling the probability of use of land units characterized by discrete and continuous measures, we present a Bayesian random-effects model to assess resource selection. This model provides simultaneous estimation of both individual- and population-level selection. Deviance information criterion (DIC), a Bayesian alternative to AIC that is sample-size specific, is used for model selection. Aerial radiolocation data from 76 adult female caribou (Rangifer tarandus) and calf pairs during 1 year on an Arctic coastal plain calving ground were used to illustrate models and assess population-level selection of landscape attributes, as well as individual heterogeneity of selection. Landscape attributes included elevation, NDVI (a measure of forage greenness), and land cover-type classification. Results from the first of a 2-stage model-selection procedure indicated that there is substantial heterogeneity among cow-calf pairs with respect to selection of the landscape attributes. In the second stage, selection of models with heterogeneity included indicated that at the population-level, NDVI and land cover class were significant attributes for selection of different landscapes by pairs on the calving ground. Population-level selection coefficients indicate that the pairs generally select landscapes with higher levels of NDVI, but the relationship is quadratic. The highest rate of selection occurs at values of NDVI less than the maximum observed. Results for land cover-class selections coefficients indicate that wet sedge, moist sedge, herbaceous tussock tundra, and shrub tussock tundra are selected at approximately the same rate, while alpine and sparsely vegetated landscapes are selected at a lower rate. Furthermore, the variability in selection by individual caribou for moist sedge and sparsely vegetated landscapes is large relative to the variability in selection of other land cover types. The example analysis illustrates that, while sometimes computationally intense, a

African rice (Oryza glaberrima) cultivation in the Togo Hills: ecological and socio-cultural cues in farmer seed selection and development

NARCIS (Netherlands)

Teeken, B.W.E.

2015-01-01

Abstract

Teeken B (2015). African rice (Oryza glaberrima) cultivation in the Togo Hills: ecological and socio-cultural cues in farmer seed selection and development. PhD thesis, Wageningen University, The Netherlands, 306 pp. The low adoption rates of

Using Culturally Sensitive Media Messages to Reduce HIV-associated Sexual Behavior in High-risk African-American Adolescents: Results from a Randomized Trial

Science.gov (United States)

Sznitman, Sharon; Vanable, Peter A.; Carey, Michael P.; Hennessy, Michael; Brown, Larry K.; Valois, Robert F.; Stanton, Bonita F.; Salazar, Laura F.; DiClemente, Ralph; Farber, Naomi; Romer, Daniel

2010-01-01

Purpose To test the long-term effects of a mass media intervention that used culturally and developmentally appropriate messages to enhance HIV-preventive beliefs and behavior of high-risk African-American adolescents. Methods Television and radio messages were delivered over three years in two cities (Syracuse, NY and Macon, GA) that were randomly selected within each of two regionally matched city pairs with the other cities (Providence, RI and Columbia, SC) serving as controls. African American adolescents ages 14 to 17 (N = 1710), recruited in the four cities over a 16-month period, completed audio computer-assisted self-interviews at recruitment and again at 3, 6, 12 and 18-months post-recruitment to assess the long-term effects of the media program. To identify the unique effects of the media intervention, youth who completed at least one follow-up and who did not test positive for any of three sexually transmitted infections at recruitment or at 6 and 12-month follow-up were retained for analysis (N=1346). Results The media intervention reached virtually all of the adolescents in the trial and produced a range of effects including improved normative condom-use negotiation expectancies and increased sex refusal self-efficacy. Most importantly, older adolescents (ages 16-17) exposed to the media program exhibited a less risky age trajectory of unprotected sex than those in the non-media cities. Conclusions Culturally tailored mass media messages delivered consistently over time have the potential to reach a large audience of high-risk adolescents, to support changes in HIV-preventive beliefs, and to reduce HIV-associated risk behaviors among older youth. PMID:21856515

Comparing fairness perceptions of personnel selection techniques of American, French and South African job applicants

Directory of Open Access Journals (Sweden)

Delene Visser

2001-12-01

Full Text Available The purpose of the study was to determine whether job applicants' perceptions of commonly used selection procedures vary across nationalities, because a negative impression of prospective employers that use selection techniques that are viewed as unfair, may result. In this study the fairness perceptions of 179 South African employees were compared with results obtained with 142 American and 117 French participants with regard to ten selection techniques using the framework of organisational justice theory. Opsomming Die doel van die ondersoek was om te bepaal of werkaansoekers van verskillende nasionaliteite se persepsies van bekende keuringsprosedures verskil. Indien voomemende werkgewers keuringstegnieke wat as onbillik beskou word, gebruik, kan 'n negatiewe beeld van hul organisasies geskep word. In hierdie studie is 179 Suid-Afrikaanse werknemers se persepsies van tien keuringstegnieke binne die raamwerk van organisasiebillikheidsteone vergelyk met persepsies van 142 Amerikaanse en 117 Franse respondente, In die algemeen was die Suid-Afrikaanse Wit groep die positiefste teenoor die keuringstegnieke.

The signature of positive selection at randomly chosen loci.

Science.gov (United States)

Przeworski, Molly

2002-03-01

In Drosophila and humans, there are accumulating examples of loci with a significant excess of high-frequency-derived alleles or high levels of linkage disequilibrium, relative to a neutral model of a random-mating population of constant size. These are features expected after a recent selective sweep. Their prevalence suggests that positive directional selection may be widespread in both species. However, as I show here, these features do not persist long after the sweep ends: The high-frequency alleles drift to fixation and no longer contribute to polymorphism, while linkage disequilibrium is broken down by recombination. As a result, loci chosen without independent evidence of recent selection are not expected to exhibit either of these features, even if they have been affected by numerous sweeps in their genealogical history. How then can we explain the patterns in the data? One possibility is population structure, with unequal sampling from different subpopulations. Alternatively, positive selection may not operate as is commonly modeled. In particular, the rate of fixation of advantageous mutations may have increased in the recent past.

The history of African trypanosomiasis

Directory of Open Access Journals (Sweden)

Steverding Dietmar

2008-02-01

Full Text Available Abstract The prehistory of African trypanosomiasis indicates that the disease may have been an important selective factor in the evolution of hominids. Ancient history and medieval history reveal that African trypanosomiasis affected the lives of people living in sub-Saharan African at all times. Modern history of African trypanosomiasis revolves around the identification of the causative agents and the mode of transmission of the infection, and the development of drugs for treatment and methods for control of the disease. From the recent history of sleeping sickness we can learn that the disease can be controlled but probably not be eradicated. Current history of human African trypanosomiasis has shown that the production of anti-sleeping sickness drugs is not always guaranteed, and therefore, new, better and cheaper drugs are urgently required.

African communalism and globalization | Etta | African Research ...

African Journals Online (AJOL)

African Research Review. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 10, No 3 (2016) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

Differential privacy-based evaporative cooling feature selection and classification with relief-F and random forests.

Science.gov (United States)

Le, Trang T; Simmons, W Kyle; Misaki, Masaya; Bodurka, Jerzy; White, Bill C; Savitz, Jonathan; McKinney, Brett A

2017-09-15

Classification of individuals into disease or clinical categories from high-dimensional biological data with low prediction error is an important challenge of statistical learning in bioinformatics. Feature selection can improve classification accuracy but must be incorporated carefully into cross-validation to avoid overfitting. Recently, feature selection methods based on differential privacy, such as differentially private random forests and reusable holdout sets, have been proposed. However, for domains such as bioinformatics, where the number of features is much larger than the number of observations p≫n , these differential privacy methods are susceptible to overfitting. We introduce private Evaporative Cooling, a stochastic privacy-preserving machine learning algorithm that uses Relief-F for feature selection and random forest for privacy preserving classification that also prevents overfitting. We relate the privacy-preserving threshold mechanism to a thermodynamic Maxwell-Boltzmann distribution, where the temperature represents the privacy threshold. We use the thermal statistical physics concept of Evaporative Cooling of atomic gases to perform backward stepwise privacy-preserving feature selection. On simulated data with main effects and statistical interactions, we compare accuracies on holdout and validation sets for three privacy-preserving methods: the reusable holdout, reusable holdout with random forest, and private Evaporative Cooling, which uses Relief-F feature selection and random forest classification. In simulations where interactions exist between attributes, private Evaporative Cooling provides higher classification accuracy without overfitting based on an independent validation set. In simulations without interactions, thresholdout with random forest and private Evaporative Cooling give comparable accuracies. We also apply these privacy methods to human brain resting-state fMRI data from a study of major depressive disorder. Code

Investigating the influence of African American and African Caribbean race on primary care doctors' decision making about depression.

Science.gov (United States)

Adams, A; Vail, L; Buckingham, C D; Kidd, J; Weich, S; Roter, D

2014-09-01

This paper explores differences in how primary care doctors process the clinical presentation of depression by African American and African-Caribbean patients compared with white patients in the US and the UK. The aim is to gain a better understanding of possible pathways by which racial disparities arise in depression care. One hundred and eight doctors described their thought processes after viewing video recorded simulated patients presenting with identical symptoms strongly suggestive of depression. These descriptions were analysed using the CliniClass system, which captures information about micro-components of clinical decision making and permits a systematic, structured and detailed analysis of how doctors arrive at diagnostic, intervention and management decisions. Video recordings of actors portraying black (both African American and African-Caribbean) and white (both White American and White British) male and female patients (aged 55 years and 75 years) were presented to doctors randomly selected from the Massachusetts Medical Society list and from Surrey/South West London and West Midlands National Health Service lists, stratified by country (US v.UK), gender, and years of clinical experience (less v. very experienced). Findings demonstrated little evidence of bias affecting doctors' decision making processes, with the exception of less attention being paid to the potential outcomes associated with different treatment options for African American compared with White American patients in the US. Instead, findings suggest greater clinical uncertainty in diagnosing depression amongst black compared with white patients, particularly in the UK. This was evident in more potential diagnoses. There was also a tendency for doctors in both countries to focus more on black patients' physical rather than psychological symptoms and to identify endocrine problems, most often diabetes, as a presenting complaint for them. This suggests that doctors in both countries

Age-Related Patterns in Social Networks among European Americans and African Americans: Implications for Socioemotional Selectivity across the Life Span.

Science.gov (United States)

Fung, Helene H.; Carstensen, Laura L.; Lang, Frieder, R.

2001-01-01

Tests socioemotional selectivity theory among African Americans and European Americans. Older people reported as many close partners but fewer peripheral partners as their younger counterparts, thus confirming the theory. A greater percentage of close social partners in social networks related to lower levels of happiness among the young age group…

Attrition of undergraduate nursing students at selected South African universities

Directory of Open Access Journals (Sweden)

Erna Roos

2016-08-01

Full Text Available Background: The nursing profession forms the backbone of many healthcare systems. It therefore needs a consistent supply of registered nurses to deliver continuous and safe quality healthcare, and to replace the nurses leaving or retiring from the profession. Attrition actively occurs among nursing students in South Africa and threatens the future supply of registered nurses. Aim: The aim of the study was to describe the attrition rate at selected South African universities and the factors influencing undergraduate nursing students to discontinue their nursing studies at these universities. Method: A quantitative descriptive design was followed. Heads of the nursing departments at the selected universities captured data with a specifically designed questionnaire. Thereafter their former nursing students provided information via a structured telephonic interview on the reasons why they discontinued the nursing programme. Results: The study revealed that attrition of undergraduate nursing students for three intake years (2007, 2008 and 2009 at the participating universities was between 39.3% and 58.7%. Academic and financial reasons as well as poor wellness and health were the main causes for attrition. Another factor was failure to cope with the demands of the clinical environment. Conclusion: Attrition might not occur immediately when a nursing student is challenged, as the student might exploit the various types of support offered. Although some nursing students do benefit from the offered support, a large number of nursing students still discontinue the undergraduate nursing programme.

Bandwidth selection in smoothing functions | Kibua | East African ...

African Journals Online (AJOL)

... inexpensive and, hence, worth adopting. We argue that the bandwidth parameter is determined by two factors: the kernel function and the length of the smoothing region. We give an illustrative example of its application using real data. Keywords: Kernel, Smoothing functions, Bandwidth > East African Journal of Statistics ...

Hand-arm vibration syndrome in South African gold miners.

Science.gov (United States)

Nyantumbu, Busi; Barber, Chris M; Ross, Mary; Curran, Andrew D; Fishwick, David; Dias, Belinda; Kgalamono, Spo; Phillips, James I

2007-01-01

Hand-arm vibration syndrome (HAVS) is associated with the use of hand-held vibrating tools. Affected workers may experience symptoms of tingling, numbness, loss of grip strength and pain. Loss of dexterity may impair everyday activities, and potentially increase the risk of occupational accidents. Although high vibration levels (up to 31 m/s(2)) have been measured in association with rock drills, HAVS has not been scientifically evaluated in the South African mining industry. The aim of this study was to determine the prevalence and severity of HAVS in South African gold miners, and to identify the tools responsible. A cross-sectional study was conducted in a single South African gold-mine. Participants were randomly selected from mineworkers returning from annual leave, comprising 156 subjects with occupational exposure to vibration, and 140 workers with no exposure. Miners who consented to participate underwent a clinical HAVS assessment following the UK Health and Safety Laboratory protocol. The prevalence of HAVS in vibration-exposed gold miners was 15%, with a mean latent period of 5.6 years. Among the non-exposed comparison group, 5% had signs and symptoms indistinguishable from HAVS. This difference was statistically significant (P < 0.05). All the cases of HAVS gave a history of exposure to rock drills. The study has diagnosed the first cases of HAVS in the South African mining industry. The prevalence of HAVS was lower than expected, and possible explanations for this may include a survivor population, and lack of vascular symptom reporting due to warm-ambient temperatures.

Interference-aware random beam selection schemes for spectrum sharing systems

KAUST Repository

Abdallah, Mohamed

2012-10-19

Spectrum sharing systems have been recently introduced to alleviate the problem of spectrum scarcity by allowing secondary unlicensed networks to share the spectrum with primary licensed networks under acceptable interference levels to the primary users. In this work, we develop interference-aware random beam selection schemes that provide enhanced performance for the secondary network under the condition that the interference observed by the receivers of the primary network is below a predetermined/acceptable value. We consider a secondary link composed of a transmitter equipped with multiple antennas and a single-antenna receiver sharing the same spectrum with a primary link composed of a single-antenna transmitter and a single-antenna receiver. The proposed schemes select a beam, among a set of power-optimized random beams, that maximizes the signal-to-interference-plus-noise ratio (SINR) of the secondary link while satisfying the primary interference constraint for different levels of feedback information describing the interference level at the primary receiver. For the proposed schemes, we develop a statistical analysis for the SINR statistics as well as the capacity and bit error rate (BER) of the secondary link.

Traditional African Religion: A Resource Unit.

Science.gov (United States)

Garland, William E.

This resource unit is based on research conducted by Lynn Mitchell and Ernest Valenzuela, experienced classroom teachers of African history and culture. The unit consists of an introduction by Mr. Garland and two major parts. Part I is an annotated bibliography of selected sources on various aspects of traditional African Religion useful in…

South African medical schools: Current state of selection criteria and medical students' demographic profile.

Science.gov (United States)

van der Merwe, L J; van Zyl, G J; St Clair Gibson, A; Viljoen, M; Iputo, J E; Mammen, M; Chitha, W; Perez, A M; Hartman, N; Fonn, S; Green-Thompson, L; Ayo-Ysuf, O A; Botha, G C; Manning, D; Botha, S J; Hift, R; Retief, P; van Heerden, B B; Volmink, J

2015-12-16

Selection of medical students at South African (SA) medical schools must promote equitable and fair access to students from all population groups, while ensuring optimal student throughput and success, and training future healthcare practitioners who will fulfil the needs of the local society. In keeping with international practices, a variety of academic and non-academic measures are used to select applicants for medical training programmes in SA medical schools. To provide an overview of the selection procedures used by all eight medical schools in SA, and the student demographics (race and gender) at these medical schools, and to determine to what extent collective practices are achieving the goals of student diversity and inclusivity. A retrospective, quantitative, descriptive study design was used. All eight medical schools in SA provided information regarding selection criteria, selection procedures, and student demographics (race and gender). Descriptive analysis of data was done by calculating frequencies and percentages of the variables measured. Medical schools in SA make use of academic and non-academic criteria in their selection processes. The latter include indices of socioeconomic disadvantage. Most undergraduate medical students in SA are black (38.7%), followed by white (33.0%), coloured (13.4%) and Indian/Asian (13.6%). The majority of students are female (62.2%). The number of black students is still proportionately lower than in the general population, while other groups are overrepresented. Selection policies for undergraduate medical programmes aimed at redress should be continued and further refined, along with the provision of support to ensure student success.

The Toyota Production Systems fundamental nature at selected South African organisations A learning perspective

Directory of Open Access Journals (Sweden)

Nortje, F. D.

2013-05-01

Full Text Available The Toyota Production System (TPS has been cited as being the pinnacle of continuous improvement approaches in manufacturing organisations, and many models of the TPS are well known. However, some authors question the effectiveness of established approaches, and propose Batesons theory of learning [1] to be an effective way to explain phenomena like the TPS. This paper investigates the degree to which TPS elements are found in selected South African organisations. It constructs a model of the TPS using Bateson's theory of learning as a framework. The adoption of TPS elements is investigated through multiple qualitative case studies in seven organisations. The analysis follows a clustering and cross-case approach combined with pattern matching. While elements vary in their use, the selected organisations practise the TPS substantially less than the model advocates, with the model being least practised in low volume job/batch manufacturing. Product-process differences and higher levels of the TPS model may clarify peculiar outcomes.

Examining African American and white outdoor recreation participation after demographic standardization on selected characteristics

Science.gov (United States)

James E. Christensen; John F. Dwyer

1995-01-01

The "marginality" explanation of differences between the outdoor recreation participation of African Americans and Whites was evaluated using demographic standardization of age, income, and education for a sample of African American and White Illinois residents. After standardization, African America/White differences in outdoor recreation participation were...

Antibodies Against Foot-and-mouth Disease (FMD) Virus in African Buffalos (Syncerus caffer) in Selected National Parks in Uganda (2001–2003)

DEFF Research Database (Denmark)

Ayebazibwe, C.; Mwiine, F. N.; Balinda, S. N.

2010-01-01

In East Africa, the foot-and-mouth disease (FMD) virus (FMDV) isolates have over time included serotypes O, A, C, Southern African Territories (SAT) 1 and SAT 2, mainly from livestock. SAT 3 has only been isolated in a few cases and only in African buffalos (Syncerus caffer). To investigate...... the presence of antibodies against FMDV serotypes in wildlife in Uganda, serological studies were performed on buffalo serum samples collected between 2001 and 2003. Thirty-eight samples from African buffalos collected from Lake Mburo, Kidepo Valley, Murchison Falls and Queen Elizabeth National Parks were...... screened using Ceditest® FMDV NS to detect antibodies against FMDV non-structural proteins (NSP). The seroprevalence of antibodies against non-structural proteins was 74%. To characterize FMDV antibodies, samples were selected and titrated using serotype-specific solid phase blocking enzyme linked...

Topology-selective jamming of fully-connected, code-division random-access networks

Science.gov (United States)

Polydoros, Andreas; Cheng, Unjeng

1990-01-01

The purpose is to introduce certain models of topology selective stochastic jamming and examine its impact on a class of fully-connected, spread-spectrum, slotted ALOHA-type random access networks. The theory covers dedicated as well as half-duplex units. The dominant role of the spatial duty factor is established, and connections with the dual concept of time selective jamming are discussed. The optimal choices of coding rate and link access parameters (from the users' side) and the jamming spatial fraction are numerically established for DS and FH spreading.

African Research Review

African Journals Online (AJOL)

Prof

imports over exports leading to unfavourable balance of payments, low domestic ... on the subject examine the effect of FDI on economic growth and a few ..... Given that the data sample in this thesis covers the selected African countries,.

Strengthening African Union for African Integration: An African ...

African Journals Online (AJOL)

Log in or Register to get access to full text downloads. ... in the international state system and seek for African initiative in solving African problems. ... of the African Union by examining the efforts of African Leaders towards African integration, ...

The African Credit Trap

OpenAIRE

Svetlana Andrianova; Badi H. Baltagi; Panicos O. Demetriades; David Fielding

2010-01-01

We put forward a plausible explanation of African financial underdevelopment in the form of a bad credit market equilibrium. Utilising an appropriately modified IO model of banking, we show that the root of the problem could be unchecked moral hazard (strategic loan defaults) or adverse selection (a lack of good projects). We provide empirical evidence from a large panel of African banks which suggests that loan defaults are a major factor inhibiting bank lending when the quality of regulatio...

Peculiarities of the statistics of spectrally selected fluorescence radiation in laser-pumped dye-doped random media

Science.gov (United States)

Yuvchenko, S. A.; Ushakova, E. V.; Pavlova, M. V.; Alonova, M. V.; Zimnyakov, D. A.

2018-04-01

We consider the practical realization of a new optical probe method of the random media which is defined as the reference-free path length interferometry with the intensity moments analysis. A peculiarity in the statistics of the spectrally selected fluorescence radiation in laser-pumped dye-doped random medium is discussed. Previously established correlations between the second- and the third-order moments of the intensity fluctuations in the random interference patterns, the coherence function of the probe radiation, and the path difference probability density for the interfering partial waves in the medium are confirmed. The correlations were verified using the statistical analysis of the spectrally selected fluorescence radiation emitted by a laser-pumped dye-doped random medium. Water solution of Rhodamine 6G was applied as the doping fluorescent agent for the ensembles of the densely packed silica grains, which were pumped by the 532 nm radiation of a solid state laser. The spectrum of the mean path length for a random medium was reconstructed.

Print versus a culturally-relevant Facebook and text message delivered intervention to promote physical activity in African American women: a randomized pilot trial.

Science.gov (United States)

Joseph, Rodney P; Keller, Colleen; Adams, Marc A; Ainsworth, Barbara E

2015-03-27

African American women report insufficient physical activity and are disproportionally burdened by associated disease conditions; indicating the need for innovative approaches to promote physical activity in this underserved population. Social media platforms (i.e. Facebook) and text messaging represent potential mediums to promote physical activity. This paper reports the results of a randomized pilot trial evaluating a theory-based (Social Cognitive Theory) multi-component intervention using Facebook and text-messages to promote physical activity among African American women. Participants (N = 29) were randomly assigned to receive one of two multi-component physical activity interventions over 8 weeks: a culturally-relevant, Social Cognitive Theory-based, intervention delivered by Facebook and text message (FI) (n = 14), or a non-culturally tailored print-based intervention (PI) (n = 15) consisting of promotion brochures mailed to their home. The primary outcome of physical activity was assessed by ActiGraph GT3X+ accelerometers. Secondary outcomes included self-reported physical activity, physical activity-related psychosocial variables, and participant satisfaction. All randomized participants (N = 29) completed the study. Accelerometer measured physical activity showed that FI participants decreased sedentary time (FI = -74 minutes/week vs. PI = +118 minute/week) and increased light intensity (FI = +95 minutes/week vs. PI = +59 minutes/week) and moderate-lifestyle intensity physical activity (FI = + 27 minutes/week vs. PI = -34 minutes/week) in comparison to PI participants (all P's  .05). Results of secondary outcomes showed that in comparison to the PI, FI participants self-reported greater increases in moderate-to-vigorous physical activity (FI = +62 minutes/week vs. PI = +6 minutes/week; P = .015) and had greater enhancements in self-regulation for physical activity (P program to a friend

Performance Evaluation of West African Dwarf (WAD) Goats fed ...

African Journals Online (AJOL)

This study investigated the effect of replacing Pennisetum purpureum with unripe plantain peels on the performance of West African Dwarf Goats. Thirty buck kids with an average weight of 7.00 ± 0.55kg were randomly assigned to three dietary treatment groups with ten bucks per treatment in a completely randomized ...

How student teachers understand African philosophy

Directory of Open Access Journals (Sweden)

Matsephe M. Letseka

2012-10-01

Full Text Available The question ‘What constitutes African philosophy?’ was first raised with the publication of Placide Tempels’s seminal work Bantu philosophy in 1959. Tempels’s book inevitably elicited considerable critical response from African philosophers, which culminated in a wide range of publications such as Wiredu’s (1980 Philosophy and an African culture, Hountondji’s (1983 African philosophy: Myth and reality, Oruka’s (1990 Sage philosophy: Indigenous thinkers and modern debate on African philosophy, Shutte’s (1993 Philosophy for Africa, Masolo’s (1994 African philosophy in search of identity and Gyekye’s (1995 An essay of African philosophical thought: The Akan conceptual scheme. It has been over 60 years since the publication of Temples’s book and there continues to be serious debate about African philosophy. This article sought to contribute to the debate on the various conceptions of African philosophy, but with a focus on the challenges of teaching African philosophy to Philosophy of Education students at an open distance learning institution in South Africa. This article discussed the tendency amongst undergraduate Philosophy of Education students to conflate and reduce African philosophy to African cultures and traditions, and to the notion of ubuntu, and sought to understand the reasons for students’ inclination to treat African philosophy in this way. It examined students’ background knowledge of African philosophy, their critical thinking skills and whether their official study materials are selected and packaged in a manner that, in fact, adds to the challenges they face. Finally, the article explored the ways in which Philosophy of Education lecturers can adapt their pedagogy to provide students with a better understanding of African philosophy.

Depression in the South African workplace | Stander | South African ...

African Journals Online (AJOL)

South African Journal of Psychiatry. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 22, No 1 (2016) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Evidence for natural selection at the melanocortin-3 receptor gene in European and African populations.

Science.gov (United States)

Yoshiuchi, Issei

2016-08-01

Obesity is increasing steadily in worldwide prevalence and is known to cause serious health problems in association with type 2 diabetes mellitus (T2DM), including hypertension, stroke, and cardiovascular diseases. According to the thrifty gene hypothesis, the natural selection of obesity-related genes is important during feast and famine because they control body weight and fat levels. Past human adaptations to environmental changes in food supply, lifestyle, and geography may have influenced the selection of genes associated with the metabolism of glucose, lipids, and energy. The melanocortin-3 receptor gene (MC3R) is associated with obesity, with MC3R-deficient mice showing increased fat mass. MC3R variations are also linked with childhood obesity and insulin resistance. Here, we aimed to uncover evidence of selection at MC3R. We performed a three-step method to detect selection at MC3R using HapMap population data. We used Wright's F statistics as a measure of population differentiation, the long-range haplotype test to identify extended haplotypes, and the integrated haplotype score (iHS) to detect selection at MC3R. We observed high population differentiation between European and African populations at two MC3R childhood obesity- and insulin resistance-associated single-nucleotide polymorphisms (rs3746619 and rs3827103) using Wright's F statistics. The iHS revealed evidence of natural selection at MC3R. These findings provide evidence for natural selection at MC3R. Further investigation is warranted into adaptive evolution at T2DM- and obesity-associated genes.

Signatures of positive selection in African Butana and Kenana dairy zebu cattle.

Science.gov (United States)

Bahbahani, Hussain; Salim, Bashir; Almathen, Faisal; Al Enezi, Fahad; Mwacharo, Joram M; Hanotte, Olivier

2018-01-01

Butana and Kenana are two types of zebu cattle found in Sudan. They are unique amongst African indigenous zebu cattle because of their high milk production. Aiming to understand their genome structure, we genotyped 25 individuals from each breed using the Illumina BovineHD Genotyping BeadChip. Genetic structure analysis shows that both breeds have an admixed genome composed of an even proportion of indicine (0.75 ± 0.03 in Butana, 0.76 ± 0.006 in Kenana) and taurine (0.23 ± 0.009 in Butana, 0.24 ± 0.006 in Kenana) ancestries. We also observe a proportion of 0.02 to 0.12 of European taurine ancestry in ten individuals of Butana that were sampled from cattle herds in Tamboul area suggesting local crossbreeding with exotic breeds. Signatures of selection analyses (iHS and Rsb) reveal 87 and 61 candidate positive selection regions in Butana and Kenana, respectively. These regions span genes and quantitative trait loci (QTL) associated with biological pathways that are important for adaptation to marginal environments (e.g., immunity, reproduction and heat tolerance). Trypanotolerance QTL are intersecting candidate regions in Kenana cattle indicating selection pressure acting on them, which might be associated with an unexplored level of trypanotolerance in this cattle breed. Several dairy traits QTL are overlapping the identified candidate regions in these two zebu cattle breeds. Our findings underline the potential to improve dairy production in the semi-arid pastoral areas of Africa through breeding improvement strategy of indigenous local breeds.

A community-integrated home based depression intervention for older African Americans: descripton of the Beat the Blues randomized trial and intervention costs

Directory of Open Access Journals (Sweden)

Gitlin Laura N

2012-02-01

Full Text Available Abstract Background Primary care is the principle setting for depression treatment; yet many older African Americans in the United States fail to report depressive symptoms or receive the recommended standard of care. Older African Americans are at high risk for depression due to elevated rates of chronic illness, disability and socioeconomic distress. There is an urgent need to develop and test new depression treatments that resonate with minority populations that are hard-to-reach and underserved and to evaluate their cost and cost-effectiveness. Methods/Design Beat the Blues (BTB is a single-blind parallel randomized trial to assess efficacy of a non-pharmacological intervention to reduce depressive symptoms and improve quality of life in 208 African Americans 55+ years old. It involves a collaboration with a senior center whose care management staff screen for depressive symptoms (telephone or in-person using the Patient Health Questionnaire (PHQ-9. Individuals screened positive (PHQ-9 ≥ 5 on two separate occasions over 2 weeks are referred to local mental health resources and BTB. Interested and eligible participants who consent receive a baseline home interview and then are randomly assigned to receive BTB immediately or 4 months later (wait-list control. All participants are interviewed at 4 (main study endpoint and 8 months at home by assessors masked to study assignment. Licensed senior center social workers trained in BTB meet with participants at home for up to 10 sessions over 4 months to assess care needs, make referrals/linkages, provide depression education, instruct in stress reduction techniques, and use behavioral activation to identify goals and steps to achieve them. Key outcomes include reduced depressive symptoms (primary, reduced anxiety and functional disability, improved quality of life, and enhanced depression knowledge and behavioral activation (secondary. Fidelity is enhanced through procedure manuals and staff

Blind Measurement Selection: A Random Matrix Theory Approach

KAUST Repository

Elkhalil, Khalil

2016-12-14

This paper considers the problem of selecting a set of $k$ measurements from $n$ available sensor observations. The selected measurements should minimize a certain error function assessing the error in estimating a certain $m$ dimensional parameter vector. The exhaustive search inspecting each of the $n\\\\choose k$ possible choices would require a very high computational complexity and as such is not practical for large $n$ and $k$. Alternative methods with low complexity have recently been investigated but their main drawbacks are that 1) they require perfect knowledge of the measurement matrix and 2) they need to be applied at the pace of change of the measurement matrix. To overcome these issues, we consider the asymptotic regime in which $k$, $n$ and $m$ grow large at the same pace. Tools from random matrix theory are then used to approximate in closed-form the most important error measures that are commonly used. The asymptotic approximations are then leveraged to select properly $k$ measurements exhibiting low values for the asymptotic error measures. Two heuristic algorithms are proposed: the first one merely consists in applying the convex optimization artifice to the asymptotic error measure. The second algorithm is a low-complexity greedy algorithm that attempts to look for a sufficiently good solution for the original minimization problem. The greedy algorithm can be applied to both the exact and the asymptotic error measures and can be thus implemented in blind and channel-aware fashions. We present two potential applications where the proposed algorithms can be used, namely antenna selection for uplink transmissions in large scale multi-user systems and sensor selection for wireless sensor networks. Numerical results are also presented and sustain the efficiency of the proposed blind methods in reaching the performances of channel-aware algorithms.

Use of electric bedding devices and risk of breast cancer in African-American women.

Science.gov (United States)

Zhu, Kangmin; Hunter, Sandra; Payne-Wilks, Kathleen; Roland, Chanel L; Forbes, Digna S

2003-10-15

In this case-control study, the authors aimed to examine whether use of an electric bedding device increased breast cancer risk in African-American women. Cases were 304 African-American patients diagnosed with breast cancer during 1995-1998 who were aged 20-64 years and lived in one of three Tennessee counties. Controls were 305 African-American women without breast cancer who were selected through random digit dialing and frequency-matched to cases by age and county. Information on the use of an electric blanket or heated water bed and other risk factors was collected through telephone interviews. Breast cancer risk associated with use of an electric bedding device increased with the number of years of use, the number of seasons of use, and the length of time of use during sleep. When women who used an electric bedding device for more than 6 months per year (and therefore were more likely to have used a heated water bed, which generates lower magnetic fields) were excluded, the corresponding dose-response relations were more striking. Similar trends in dose response were shown in both premenopausal and postmenopausal women and for both estrogen receptor-positive and estrogen receptor-negative tumors. The use of electric bedding devices may increase breast cancer risk in African-American women aged 20-64 years. Such an association might not vary substantially by menopausal status or estrogen receptor status.

Hypertension Prevalence, Awareness and Control Levels among Ghawarna: An African-Descendant Ethnic Minority in the Jordan Valley.

Science.gov (United States)

Kheirallah, Khalid A; Liswi, Mohammed; Alazab, Rami; Bataineh, Zeyad; Alzyoud, Sukaina; Alsulaiman, Jomana; Jaddou, Hashem

2015-08-07

Treatment and control of hypertension (HTN) is a challenging issue as undiagnosed HTN prevalence seems to be high among certain ethnic groups, such as African-descendant populations. The current study attempted to measure HTN prevalence, awareness and control levels among Ghawarna, an African-descendant ethnic group living in the Jordan Valley (Al-Ghawr). A cross-sectional study was conducted in a community of Ghawarna between March and June 2013 in Ghawr Al-Mazraa Village in the southern part of the Jordan Valley. A total of 517 participants, aged >25 years, were randomly selected using cluster random sampling technique. Data were collected using an interviewer-administrated questionnaire and on-location measurement of blood pressure (BP), height, and weight. Prevalence rates were compared by sex and age groups using chi-square test while backward selection logistic regression analysis was used to identify predictors of HTN. We found 229 (44.3%) of the 517 participants had HTN. Of those 229 hypertensives, 146 (28.2%) participants were discovered to have HTN for the "first time." Only 23 of the 83 who were aware of their hypertension had their BP controlled. When we added the undiagnosed HTN (n=146) to the uncontrolled HTN (n=60), the prevalence of uncontrolled HTN became 90% (206/229). Older age, higher BMI, diabetes mellitus, and dyslipidemia were associated with having HTN. HTN prevalence, awareness and control levels are alarming among Ghawarna.

The European “African print” and the direction of authentic African ...

African Journals Online (AJOL)

The paper investigates the nature of machine-produced fabric commercially termed “African prints” by focusing on a select sample of these prints. It establishes that the general design characteristics of these prints are an amalgam of mainly Javanese, Indian, Chinese, Arab and European artistic traditions. Attempts at ...

Using ArcMap, Google Earth, and Global Positioning Systems to select and locate random households in rural Haiti.

Science.gov (United States)

Wampler, Peter J; Rediske, Richard R; Molla, Azizur R

2013-01-18

A remote sensing technique was developed which combines a Geographic Information System (GIS); Google Earth, and Microsoft Excel to identify home locations for a random sample of households in rural Haiti. The method was used to select homes for ethnographic and water quality research in a region of rural Haiti located within 9 km of a local hospital and source of health education in Deschapelles, Haiti. The technique does not require access to governmental records or ground based surveys to collect household location data and can be performed in a rapid, cost-effective manner. The random selection of households and the location of these households during field surveys were accomplished using GIS, Google Earth, Microsoft Excel, and handheld Garmin GPSmap 76CSx GPS units. Homes were identified and mapped in Google Earth, exported to ArcMap 10.0, and a random list of homes was generated using Microsoft Excel which was then loaded onto handheld GPS units for field location. The development and use of a remote sensing method was essential to the selection and location of random households. A total of 537 homes initially were mapped and a randomized subset of 96 was identified as potential survey locations. Over 96% of the homes mapped using Google Earth imagery were correctly identified as occupied dwellings. Only 3.6% of the occupants of mapped homes visited declined to be interviewed. 16.4% of the homes visited were not occupied at the time of the visit due to work away from the home or market days. A total of 55 households were located using this method during the 10 days of fieldwork in May and June of 2012. The method used to generate and field locate random homes for surveys and water sampling was an effective means of selecting random households in a rural environment lacking geolocation infrastructure. The success rate for locating households using a handheld GPS was excellent and only rarely was local knowledge required to identify and locate households. This

Using ArcMap, Google Earth, and Global Positioning Systems to select and locate random households in rural Haiti

Directory of Open Access Journals (Sweden)

Wampler Peter J

2013-01-01

Full Text Available Abstract Background A remote sensing technique was developed which combines a Geographic Information System (GIS; Google Earth, and Microsoft Excel to identify home locations for a random sample of households in rural Haiti. The method was used to select homes for ethnographic and water quality research in a region of rural Haiti located within 9 km of a local hospital and source of health education in Deschapelles, Haiti. The technique does not require access to governmental records or ground based surveys to collect household location data and can be performed in a rapid, cost-effective manner. Methods The random selection of households and the location of these households during field surveys were accomplished using GIS, Google Earth, Microsoft Excel, and handheld Garmin GPSmap 76CSx GPS units. Homes were identified and mapped in Google Earth, exported to ArcMap 10.0, and a random list of homes was generated using Microsoft Excel which was then loaded onto handheld GPS units for field location. The development and use of a remote sensing method was essential to the selection and location of random households. Results A total of 537 homes initially were mapped and a randomized subset of 96 was identified as potential survey locations. Over 96% of the homes mapped using Google Earth imagery were correctly identified as occupied dwellings. Only 3.6% of the occupants of mapped homes visited declined to be interviewed. 16.4% of the homes visited were not occupied at the time of the visit due to work away from the home or market days. A total of 55 households were located using this method during the 10 days of fieldwork in May and June of 2012. Conclusions The method used to generate and field locate random homes for surveys and water sampling was an effective means of selecting random households in a rural environment lacking geolocation infrastructure. The success rate for locating households using a handheld GPS was excellent and only

Qualitative evaluation of selected social factors that impact sexual risk-taking behaviour among African students in Kwazulu-Natal, South Africa.

Science.gov (United States)

Ngidi, Ndumiso Daluxolo; Moyo, Sibusiso; Zulu, Thobile; Adam, Jamila Khatoon; Krishna, Suresh Babu Naidu

2016-12-01

The incidence of HIV and AIDS continues to be a source of great concern within universities in South Africa. Furthermore, university students constitute an important community in the intervention against the HIV/AIDS epidemic. Students in the age group of 15-24 years are at a greater risk of HIV infection than any other group in the country; yet, little is known about why they continue to engage in risky sexual practices. This study was designed to explore the sexual behaviour of students in a metropolitan Durban University of Technology in KwaZulu-Natal to understand the social factors underlying their risk of HIV infection. This is a qualitative study that used cluster sampling where the population was stratified by campus and faculty. The study population was selected using a standard randomization technique. This was a part of a multi-phased research project aimed at providing a sero-prevalence baseline and an analysis of risk-taking behaviour at a Durban University of Technology in the eThekwini Metropolitan Municipality area. The study highlights peer pressure among students as an influence in promoting high-risk sexual behaviour. Within this context, the findings revealed that university students lack the ability to negotiate risk-aware decisions especially regarding sexual relationships. This study draws attention to the perspectives of African university students regarding their risk-taking sexual practices and selected factors which influence such behaviour. The findings are not exhaustive in exploring contextual antecedents that shape students' sexual practices. However, they provide an important basis in understanding key factors which expose students to HIV infections. The study provides insights into opportunities for further studies as well as preventative implications.

Selected Abstracts from NSA 2014 | Onyeka | African Journal of ...

African Journals Online (AJOL)

African Journal of Anaesthesia and Intensive Care. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 15, No 1 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. DOWNLOAD FULL TEXT Open Access ...

Spirometry of healthy adult South African men | Louw | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 86, No 7 (1996) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Optimizing Event Selection with the Random Grid Search

Energy Technology Data Exchange (ETDEWEB)

Bhat, Pushpalatha C. [Fermilab; Prosper, Harrison B. [Florida State U.; Sekmen, Sezen [Kyungpook Natl. U.; Stewart, Chip [Broad Inst., Cambridge

2017-06-29

The random grid search (RGS) is a simple, but efficient, stochastic algorithm to find optimal cuts that was developed in the context of the search for the top quark at Fermilab in the mid-1990s. The algorithm, and associated code, have been enhanced recently with the introduction of two new cut types, one of which has been successfully used in searches for supersymmetry at the Large Hadron Collider. The RGS optimization algorithm is described along with the recent developments, which are illustrated with two examples from particle physics. One explores the optimization of the selection of vector boson fusion events in the four-lepton decay mode of the Higgs boson and the other optimizes SUSY searches using boosted objects and the razor variables.

Non-random mating for selection with restricted rates of inbreeding and overlapping generations

NARCIS (Netherlands)

Sonesson, A.K.; Meuwissen, T.H.E.

2002-01-01

Minimum coancestry mating with a maximum of one offspring per mating pair (MC1) is compared with random mating schemes for populations with overlapping generations. Optimum contribution selection is used, whereby $\\\\\\\\Delta F$ is restricted. For schemes with $\\\\\\\\Delta F$ restricted to 0.25% per

Recruiting African Americans into Research on Cognitive Aging

OpenAIRE

McDougall, Graham J.; Holston, Ezra C.; Wilke, Pat

2001-01-01

A total of 218 adults with an average age of seventy-eight years participated in a study of memory performance in community elders. A computer-generated random zip code list of adults ≥70 years of age was purchased and a four-phase telephone-screening plan was adopted. During the second year, the sampling plan had to be changed, with a convenience-sampling plan being adopted to recruit adequate numbers of African-American subjects. Fifty-seven percent of the African-American subjects (N = 55)...

Multicultural education and its politics | Gumbo | South African ...

African Journals Online (AJOL)

This article is an account of how multicultural education is experienced within the US society and its national school curriculum. The has had an opportunity to partly witness this situation, when he was selected as one of the South African Educators who participated in the June-July 1999 South African Transformation ...

WEST AFRICAN JOURNAL OF MEDICINE

African Journals Online (AJOL)

user1

African Programme for Onchocerciasis Control: Ophthalmological Findings in Bushenyi, Uganda ... In a cross-sectional study, 367 persons aged 10 years or older from seven selected .... down posture, and evidence of acute or torpid uveitis.

Positive Selection of Deleterious Alleles through Interaction with a Sex-Ratio Suppressor Gene in African Buffalo: A Plausible New Mechanism for a High Frequency Anomaly

NARCIS (Netherlands)

Hooft, van W.F.; Greyling, B.J.; Getz, W.M.; Helden, P.D.; Zwaan, B.J.; Bastos, A.D.S.

2015-01-01

Although generally rare, deleterious alleles can become common through genetic drift, hitchhiking or reductions in selective constraints. Here we present a possible new mechanism that explains the attainment of high frequencies of deleterious alleles in the African buffalo (Syncerus caffer)

Positive Selection of Deleterious Alleles through Interaction with a Sex-Ratio Suppressor Gene in African Buffalo: A Plausible New Mechanism for a High Frequency Anomaly

NARCIS (Netherlands)

Hooft, van W.F.; Greyling, B.J.; Getz, W.M.; Helden, van P.D.; Zwaan, B.J.; Bastos, A.D.S.

2014-01-01

Although generally rare, deleterious alleles can become common through genetic drift, hitchhiking or reductions in selective constraints. Here we present a possible new mechanism that explains the attainment of high frequencies of deleterious alleles in the African buffalo (Syncerus caffer)

Comparative Evaluations of Randomly Selected Four Point-of-Care Glucometer Devices in Addis Ababa, Ethiopia.

Science.gov (United States)

Wolde, Mistire; Tarekegn, Getahun; Kebede, Tedla

2018-05-01

Point-of-care glucometer (PoCG) devices play a significant role in self-monitoring of the blood sugar level, particularly in the follow-up of high blood sugar therapeutic response. The aim of this study was to evaluate blood glucose test results performed with four randomly selected glucometers on diabetes and control subjects versus standard wet chemistry (hexokinase) methods in Addis Ababa, Ethiopia. A prospective cross-sectional study was conducted on randomly selected 200 study participants (100 participants with diabetes and 100 healthy controls). Four randomly selected PoCG devices (CareSens N, DIAVUE Prudential, On Call Extra, i-QARE DS-W) were evaluated against hexokinase method and ISO 15197:2003 and ISO 15197:2013 standards. The minimum and maximum blood sugar values were recorded by CareSens N (21 mg/dl) and hexokinase method (498.8 mg/dl), respectively. The mean sugar values of all PoCG devices except On Call Extra showed significant differences compared with the reference hexokinase method. Meanwhile, all four PoCG devices had strong positive relationship (>80%) with the reference method (hexokinase). On the other hand, none of the four PoCG devices fulfilled the minimum accuracy measurement set by ISO 15197:2003 and ISO 15197:2013 standards. In addition, the linear regression analysis revealed that all four selected PoCG overestimated the glucose concentrations. The overall evaluation of the selected four PoCG measurements were poorly correlated with standard reference method. Therefore, before introducing PoCG devices to the market, there should be a standardized evaluation platform for validation. Further similar large-scale studies on other PoCG devices also need to be undertaken.

Measures for diffusion of solar PV in selected African countries

DEFF Research Database (Denmark)

Nygaard, Ivan; Hansen, Ulrich Elmer; Mackenzie, Gordon A.

2017-01-01

that governments’ strategies to promoting solar PV are moving from isolated projects towards frameworks for market development and that there are high expectations to upgrading in the PV value chain through local assembly of panels and local production of other system elements. Commonly identified measures include......This paper investigates how African governments are considering supporting and promoting the diffusion of solar PV. This issue is explored by examining so-called ‘technology action plans (TAPs)’, which were main outputs of the Technology Needs Assessment project implemented in 10 African countries...... from 2010 to 2013. The paper provides a review of three distinct but characteristic trajectories for PV market development in Kenya (private-led market for solar home systems), Morocco (utility-led fee-for service model) and Rwanda (donorled market for institutional systems). The paper finds...

Geography and genography: prediction of continental origin using randomly selected single nucleotide polymorphisms

Directory of Open Access Journals (Sweden)

Ramoni Marco F

2007-03-01

Full Text Available Abstract Background Recent studies have shown that when individuals are grouped on the basis of genetic similarity, group membership corresponds closely to continental origin. There has been considerable debate about the implications of these findings in the context of larger debates about race and the extent of genetic variation between groups. Some have argued that clustering according to continental origin demonstrates the existence of significant genetic differences between groups and that these differences may have important implications for differences in health and disease. Others argue that clustering according to continental origin requires the use of large amounts of genetic data or specifically chosen markers and is indicative only of very subtle genetic differences that are unlikely to have biomedical significance. Results We used small numbers of randomly selected single nucleotide polymorphisms (SNPs from the International HapMap Project to train naïve Bayes classifiers for prediction of ancestral continent of origin. Predictive accuracy was tested on two independent data sets. Genetically similar groups should be difficult to distinguish, especially if only a small number of genetic markers are used. The genetic differences between continentally defined groups are sufficiently large that one can accurately predict ancestral continent of origin using only a minute, randomly selected fraction of the genetic variation present in the human genome. Genotype data from only 50 random SNPs was sufficient to predict ancestral continent of origin in our primary test data set with an average accuracy of 95%. Genetic variations informative about ancestry were common and widely distributed throughout the genome. Conclusion Accurate characterization of ancestry is possible using small numbers of randomly selected SNPs. The results presented here show how investigators conducting genetic association studies can use small numbers of arbitrarily

African Journals Online (AJOL)

African Journals Online (AJOL)

Southern African Business Review; Effect of Globalization on Sovereignty of States Nnamdi Azikiwe University Journal of International Law and Jurisprudence; The Influence of Motivation on Employees' Performance: A Study of Some Selected Firms in Anambra State AFRREV IJAH: An International Journal of Arts and ...

What drives energy consumption in developing countries? The experience of selected African countries

International Nuclear Information System (INIS)

Keho, Yaya

2016-01-01

This study investigates the drivers of energy consumption in Sub-Saharan African countries. It applies the bounds testing approach to cointegration to time series data at individual country levels over the period from 1970 to 2011. The study finds that energy consumption is cointegrated with real GDP per capita, industrial output, imports, foreign direct investment, credit to private sector, urbanization and population. Furthermore, the sign and magnitude of long-run estimates vary significantly for a single country and across countries depending on the energy consumption variable used. Overall, the findings confirm the leading role of economic growth, industrial output, population and urbanization. Economic growth, industrial output and population have positive effects on energy consumption in the majority of countries. Given the urgent need to address climate change, African countries should adopt policies to improve energy efficiency and accelerate transition toward renewable energy. The African Renewable Energy Initiative launched at the 21st session of the United Nations Conference of the Parties (COP21) is an opportunity for African countries to provide and maintain widespread access to reliable and affordable environmentally cleaner energy to meet the requirements of rapid economic growth and improved living standards. - Highlights: •Key drivers of energy use in 12 African countries are examined. •Economic growth, industrial GDP, population and urbanization play a leading role in explaining energy use. •Urbanization has a positive effect on energy use in six countries and a negative effect in four countries. •The results obtained have useful policy implications.

Engaging African American landowners in sustainable forest management

Science.gov (United States)

John Schelhas; Sarah Hitchner; Cassandra Johnson Gaither; Rory Fraser; Viniece Jennings; Amadou Diop

2016-01-01

The Sustainable Forestry and African American Land Retention Program is a comprehensive effort to address the long-standing problem of underparticipation of African Americans in forest management. We conducted rapid appraisal baseline research for pilot projects in this program in three Southern states using a carefully selected purposive sample to enhance our...

The impact of dialogic book-sharing training on infant language and attention: a randomized controlled trial in a deprived South African community.

Science.gov (United States)

Vally, Zahir; Murray, Lynne; Tomlinson, Mark; Cooper, Peter J

2015-08-01

Dialogic book-sharing is an interactive form of shared reading. It has been shown in high income countries (HICs) to be of significant benefit to child cognitive development. Evidence for such benefit in low and middle income countries (LMICs) is scarce, although a feasibility study of our own produced encouraging findings. Accordingly, we aimed to establish the impact on child language and attention of providing training in dialogic booksharing to carers of infants in an impoverished South African community. We conducted a randomized controlled trial in Khayelitsha, an informal settlement in South Africa. Mothers of infants aged between 14 and 16 months were recruited and randomized to either 8 weeks of manualized training in dialogic book-sharing or a no-intervention control group. Independent assessments were made of infant language and attention at baseline and following training. The trial was registered (ISRCTN39953901). Ninety one carer-infant dyads were recruited and randomized to the intervention group (n = 49) or the control group (n = 42), 82 (90%) of whom were available for follow-up assessments. On a standardized carer report of infant vocabulary, compared to those in the control group, carers who received the intervention reported a significantly greater increase in the number of words understood by their infants as well as a larger increase in the number of words that their infant understood and could vocalize. Intervention group children also showed substantially greater gains on a measure of sustained attention. In line with evidence from HICs, a dialogic book-sharing programme delivered to an impoverished South African sample was shown to be of considerable benefit to the development of child language and focussed attention. The training programme, which is simple and inexpensive to deliver, has the potential to benefit child cognitive development in LMIC contexts where such development is commonly compromised. © 2014 Association for Child

Fuzzy Random λ-Mean SAD Portfolio Selection Problem: An Ant Colony Optimization Approach

Science.gov (United States)

Thakur, Gour Sundar Mitra; Bhattacharyya, Rupak; Mitra, Swapan Kumar

2010-10-01

To reach the investment goal, one has to select a combination of securities among different portfolios containing large number of securities. Only the past records of each security do not guarantee the future return. As there are many uncertain factors which directly or indirectly influence the stock market and there are also some newer stock markets which do not have enough historical data, experts' expectation and experience must be combined with the past records to generate an effective portfolio selection model. In this paper the return of security is assumed to be Fuzzy Random Variable Set (FRVS), where returns are set of random numbers which are in turn fuzzy numbers. A new λ-Mean Semi Absolute Deviation (λ-MSAD) portfolio selection model is developed. The subjective opinions of the investors to the rate of returns of each security are taken into consideration by introducing a pessimistic-optimistic parameter vector λ. λ-Mean Semi Absolute Deviation (λ-MSAD) model is preferred as it follows absolute deviation of the rate of returns of a portfolio instead of the variance as the measure of the risk. As this model can be reduced to Linear Programming Problem (LPP) it can be solved much faster than quadratic programming problems. Ant Colony Optimization (ACO) is used for solving the portfolio selection problem. ACO is a paradigm for designing meta-heuristic algorithms for combinatorial optimization problem. Data from BSE is used for illustration.

Pediatric selective mutism therapy: a randomized controlled trial.

Science.gov (United States)

Esposito, Maria; Gimigliano, Francesca; Barillari, Maria R; Precenzano, Francesco; Ruberto, Maria; Sepe, Joseph; Barillari, Umberto; Gimigliano, Raffaele; Militerni, Roberto; Messina, Giovanni; Carotenuto, Marco

2017-10-01

Selective mutism (SM) is a rare disease in children coded by DSM-5 as an anxiety disorder. Despite the disabling nature of the disease, there is still no specific treatment. The aims of this study were to verify the efficacy of six-month standard psychomotor treatment and the positive changes in lifestyle, in a population of children affected by SM. Randomized controlled trial registered in the European Clinical Trials Registry (EuDract 2015-001161-36). University third level Centre (Child and Adolescent Neuropsychiatry Clinic). Study population was composed by 67 children in group A (psychomotricity treatment) (35 M, mean age 7.84±1.15) and 71 children in group B (behavioral and educational counseling) (37 M, mean age 7.75±1.36). Psychomotor treatment was administered by trained child therapists in residential settings three times per week. Each child was treated for the whole period by the same therapist and all the therapists shared the same protocol. The standard psychomotor session length is of 45 minutes. At T0 and after 6 months (T1) of treatments, patients underwent a behavioral and SM severity assessment. To verify the effects of the psychomotor management, the Child Behavior Checklist questionnaire (CBCL) and Selective Mutism Questionnaire (SMQ) were administered to the parents. After 6 months of psychomotor treatment SM children showed a significant reduction among CBCL scores such as in social relations, anxious/depressed, social problems and total problems (Pselective mutism, even if further studies are needed. The present study identifies in psychomotricity a safe and efficacy therapy for pediatric selective mutism.

African Research Review: Submissions

African Journals Online (AJOL)

The African Research Review publishes original research output in the areas of Arts, Education, Social Sciences, Pure and applied Sciences, Engineering and ... Final selection of papers for publication in the Journal will be based on paper originality, technical quality, use of language and overall contribution to knowledge.

Differences in HIV natural history among African and non-African seroconverters in Europe and seroconverters in sub-Saharan Africa

NARCIS (Netherlands)

Pantazis, Nikos; Morrison, Charles; Amornkul, Pauli N.; Lewden, Charlotte; Salata, Robert A.; Minga, Albert; Chipato, Tsungai; Jaffe, Harold; Lakhi, Shabir; Karita, Etienne; Porter, Kholoud; Meyer, Laurence; Touloumi, Giota; del Amo, Julia; Bucher, Heiner C.; Chêne, Geneviève; Hamouda, Osamah; Pillay, Deenan; Prins, Maria; Rosinska, Magda; Sabin, Caroline; Lodi, Sara; Coughlin, Kate; Walker, Sarah; Babiker, Abdel; de Luca, Andrea; Fisher, Martin; Muga, Roberto; Zangerle, Robert; Kelleher, A. D.; Cooper, D. A.; Grey, Pat; Finlayson, Robert; Bloch, Mark; Kelleher, Tony; Ramacciotti, Tim; Gelgor, Linda; Cooper, David; Smith, Don; Gill, John; Jørgensen, Louise Bruun; Lutsar, Irja; Dabis, Francois; Thiebaut, Rodolphe; Masquelier, Bernard; Costagliola, Dominique; Guiguet, Marguerite; Geskus, Ronald; van der Helm, Jannie; Schuitemaker, Hanneke

2012-01-01

It is unknown whether HIV treatment guidelines, based on resource-rich country cohorts, are applicable to African populations. We estimated CD4 cell loss in ART-naïve, AIDS-free individuals using mixed models allowing for random intercept and slope, and time from seroconversion to clinical AIDS,

Stressors among South African soccer officials: A profile analysis ...

African Journals Online (AJOL)

The purpose of this study was to determine the contribution of selected stressors to the level of stress experienced by South African soccer officials. Forty-two South African Football Association (SAFA) accredited officials, attending a training camp in Potchefstroom, participated in this study. The group comprised of 40 male ...

Primitive polynomials selection method for pseudo-random number generator

Science.gov (United States)

Anikin, I. V.; Alnajjar, Kh

2018-01-01

In this paper we suggested the method for primitive polynomials selection of special type. This kind of polynomials can be efficiently used as a characteristic polynomials for linear feedback shift registers in pseudo-random number generators. The proposed method consists of two basic steps: finding minimum-cost irreducible polynomials of the desired degree and applying primitivity tests to get the primitive ones. Finally two primitive polynomials, which was found by the proposed method, used in pseudorandom number generator based on fuzzy logic (FRNG) which had been suggested before by the authors. The sequences generated by new version of FRNG have low correlation magnitude, high linear complexity, less power consumption, is more balanced and have better statistical properties.

Comparative multivariate analysis of biometric traits of West African Dwarf and Red Sokoto goats.

Science.gov (United States)

Yakubu, Abdulmojeed; Salako, Adebowale E; Imumorin, Ikhide G

2011-03-01

The population structure of 302 randomly selected West African Dwarf (WAD) and Red Sokoto (RS) goats was examined using multivariate morphometric analyses. This was to make the case for conservation, rational management and genetic improvement of these two most important Nigerian goat breeds. Fifteen morphometric measurements were made on each individual animal. RS goats were superior (Pgoats, three components were obtained for their RS counterparts with variation in the loading traits of each component for each breed. The Mahalanobis distance of 72.28 indicated a high degree of spatial racial separation in morphology between the genotypes. The Ward's option of the cluster analysis consolidated the morphometric distinctness of the two breeds. Application of selective breeding to genetic improvement would benefit from the detected phenotypic differentiation. Other implications for management and conservation of the goats are highlighted.

Measures for diffusion of solar PV in selected African countries

Science.gov (United States)

Nygaard, Ivan; Hansen, Ulrich Elmer; Mackenzie, Gordon; Pedersen, Mathilde Brix

2017-08-01

This paper investigates how African governments are considering supporting and promoting the diffusion of solar PV. This issue is explored by examining so-called 'technology action plans (TAPs)', which were main outputs of the Technology Needs Assessment project implemented in 10 African countries from 2010 to 2013. The paper provides a review of three distinct but characteristic trajectories for PV market development in Kenya (private-led market for solar home systems), Morocco (utility-led fee-for service model) and Rwanda (donor-led market for institutional systems). The paper finds that governments' strategies to promoting solar PV are moving from isolated projects towards frameworks for market development and that there are high expectations to upgrading in the PV value chain through local assembly of panels and local production of other system elements. Commonly identified measures include support to: local production; financing schemes; tax exemptions; establishment and reinforcement of standards; technical training; and research and development.

Job Sorting in African Labor Markets

OpenAIRE

Marcel Fafchamps; Mans Soderbom; Najy Benhassine

2006-01-01

Using matched employer-employee data from eleven African countries, we investigate if there is a job sorting in African labor markets. We find that much of the wage gap correlated with education is driven by selection across occupations and firms. This is consistent with educated workers being more effective at complex tasks like labor management. In all countries the education wage gap widens rapidly at high low levels of education. Most of the education wage gap at low levels of education c...

Structural Analysis of Insulin Minisatellite Alleles Reveals Unusually Large Differences in Diversity between Africans and Non-Africans

Science.gov (United States)

Stead, John D. H.; Jeffreys, Alec J.

2002-01-01

The insulin minisatellite (INS VNTR) associates with susceptibility to a variety of diseases. We have developed a high-resolution system for analyzing variant repeat distributions applicable to all known minisatellite alleles, irrespective of size, which allows lineages of related alleles to be identified. This system has previously revealed extremely low structural diversity in the minisatellite among northern Europeans from the United Kingdom, with all alleles belonging to one of only three highly diverged lineages called “I,” “IIIA,” and “IIIB.” To explore the origins of this remarkably limited lineage diversity, we have characterized an additional 780 alleles from three non-African and three African populations. In total, 22 highly diverged lineages were identified, with structural intermediates absent from extant populations, suggesting a bottleneck within the ancestry of all humans. The difference between levels of diversity in Africans and non-Africans is unusually large, with all 22 lineages identified in Africa compared with only three lineages seen not only in the United Kingdom but also in the other non-African populations. We also find evidence for overrepresentation of lineage I chromosomes in non-Africans. These data are consistent with a common out-of-Africa origin and an unusually tight bottleneck within the ancestry of all non-African populations, possibly combined with differential and positive selection for lineage I alleles in non-Africans. The important implications of these data for future disease-association studies are discussed. PMID:12404181

Molossid bats in an African agro-ecosystem select sugarcane fields ...

African Journals Online (AJOL)

Two coexisting species of African molossids, the little free-tailed bat, Chaerephon pumilus, and the Angolan free-tailed bat, Mops condylurus, were studied in the lowveld of Swaziland. Nine C. pumilus and five M. condylurus, all non-lactating females, were radio-tracked in order to investigate their habitat utilization.

A practice-based trial of blood pressure control in African Americans (TLC-Clinic: study protocol for a randomized controlled trial

Directory of Open Access Journals (Sweden)

Schoenthaler Antoinette

2011-12-01

Full Text Available Abstract Background Poorly controlled hypertension (HTN remains one of the most significant public health problems in the United States, in terms of morbidity, mortality, and economic burden. Despite compelling evidence supporting the beneficial effects of therapeutic lifestyle changes (TLC for blood pressure (BP reduction, the effectiveness of these approaches in primary care practices remains untested, especially among African Americans, who share a disproportionately greater burden of HTN-related outcomes. Methods/Design This randomized controlled trial tests the effectiveness of a practice-based comprehensive therapeutic lifestyle intervention, delivered through group-based counseling and motivational interviewing (MINT-TLC versus Usual Care (UC in 200 low-income, African Americans with uncontrolled hypertension. MINT-TLC is designed to help patients make appropriate lifestyle changes and develop skills to maintain these changes long-term. Patients in the MINT-TLC group attend 10 weekly group classes focused on healthy lifestyle changes (intensive phase; followed by 3 monthly individual motivational interviewing (MINT sessions (maintenance phase. The intervention is delivered by trained research personnel with appropriate treatment fidelity procedures. Patients in the UC condition receive a single individual counseling session on healthy lifestyle changes and print versions of the intervention materials. The primary outcome is within-patient change in both systolic and diastolic BP from baseline to 6 months. In addition to BP control at 6 months, other secondary outcomes include changes in the following lifestyle behaviors from baseline to 6 months: a physical activity, b weight loss, c number of daily servings of fruits and vegetables and d 24-hour urinary sodium excretion. Discussion This vanguard trial will provide information on how to refine MINT-TLC and integrate it into a standard treatment protocol for hypertensive African Americans

Prevalence of glaucoma in an urban West African population: the Tema Eye Survey.

Science.gov (United States)

Budenz, Donald L; Barton, Keith; Whiteside-de Vos, Julia; Schiffman, Joyce; Bandi, Jagadeesh; Nolan, Winifred; Herndon, Leon; Kim, Hanna; Hay-Smith, Graham; Tielsch, James M

2013-05-01

Multiple studies have found an increased prevalence, younger age at onset, and more severe course of glaucoma in people of African descent, but these findings are based on studies conducted outside Africa. To determine the prevalence of glaucoma in an urban West African population of adults. A population-based, cross-sectional study of adults 40 years and older conducted from September 1, 2006, through December 31, 2008, from 5 communities in Tema, Ghana. Participants from randomly selected clusters underwent a screening examination that consisted of visual acuity, frequency doubling perimetry, applanation tonometry, and optic disc photography. Participants who failed any of these tests were referred for complete examination, including gonioscopy, standard automated perimetry, and stereoscopic optic disc photography. A total of 6806 eligible participants were identified, and 5603 (82.3%) were enrolled in the study. The field examination referred 1869 participants (33.3%) to the clinic examination, and 1538 (82.2%) came for complete examination. A total of 362 participants were identified as having glaucoma of any type and category. Primary open-angle glaucoma was the underlying diagnosis in 342 participants (94.5%). The prevalence of primary open-angle glaucoma was 6.8% overall, increasing from 3.7% among those 40 to 49 years old to 14.6% among those 80 years and older, and was higher in men than in women in all age groups, with an overall male-female prevalence ratio of 1.5. Of the participants with glaucoma, 9 (2.5%) were blind using World Health Organization criteria, and only 12 (3.3%) were aware that they had glaucoma. The prevalence of glaucoma is higher in this urban West African population than in previous studies of people of East or South African and of non-African descent. Strategies to identify affected persons and effectively manage the burden of glaucoma are needed in West Africa.

Randomizing Roaches: Exploring the "Bugs" of Randomization in Experimental Design

Science.gov (United States)

Wagler, Amy; Wagler, Ron

2014-01-01

Understanding the roles of random selection and random assignment in experimental design is a central learning objective in most introductory statistics courses. This article describes an activity, appropriate for a high school or introductory statistics course, designed to teach the concepts, values and pitfalls of random selection and assignment…

Protocol of a randomized controlled trial of culturally sensitive interventions to improve African Americans' and non-African Americans' early, shared, and informed consideration of live kidney transplantation: the Talking About Live Kidney Donation (TALK) Study.

Science.gov (United States)

Boulware, L Ebony; Hill-Briggs, Felicia; Kraus, Edward S; Melancon, J Keith; McGuire, Raquel; Bonhage, Bobbie; Senga, Mikiko; Ephraim, Patti; Evans, Kira E; Falcone, Brenda; Troll, Misty U; Depasquale, Nicole; Powe, Neil R

2011-07-08

Live kidney transplantation (LKT) is underutilized, particularly among ethnic/racial minorities. The effectiveness of culturally sensitive educational and behavioral interventions to encourage patients' early, shared (with family and health care providers) and informed consideration of LKT and ameliorate disparities in consideration of LKT is unknown. We report the protocol of the Talking About Live Kidney Donation (TALK) Study, a two-phase study utilizing qualitative and quantitative research methods to design and test culturally sensitive interventions to improve patients' shared and informed consideration of LKT. Study Phase 1 involved the evidence-based development of culturally sensitive written and audiovisual educational materials as well as a social worker intervention to encourage patients' engagement in shared and informed consideration of LKT. In Study Phase 2, we are currently conducting a randomized controlled trial in which participants with progressing chronic kidney disease receive: 1) usual care by their nephrologists, 2) usual care plus the educational materials, or 3) usual care plus the educational materials and the social worker intervention. The primary outcome of the randomized controlled trial will include patients' self-reported rates of consideration of LKT (including family discussions of LKT, patient-physician discussions of LKT, and identification of an LKT donor). We will also assess differences in rates of consideration of LKT among African Americans and non-African Americans. The TALK Study rigorously developed and is currently testing the effectiveness of culturally sensitive interventions to improve patients' and families' consideration of LKT. Results from TALK will provide needed evidence on ways to enhance consideration of this optimal treatment for patients with end stage renal disease. ClinicalTrials.gov number, NCT00932334.

Parallel selection on TRPV6 in human populations.

Science.gov (United States)

Hughes, David A; Tang, Kun; Strotmann, Rainer; Schöneberg, Torsten; Prenen, Jean; Nilius, Bernd; Stoneking, Mark

2008-02-27

We identified and examined a candidate gene for local directional selection in Europeans, TRPV6, and conclude that selection has acted on standing genetic variation at this locus, creating parallel soft sweep events in humans. A novel modification of the extended haplotype homozygosity (EHH) test was utilized, which compares EHH for a single allele across populations, to investigate the signature of selection at TRPV6 and neighboring linked loci in published data sets for Europeans, Asians and African-Americans, as well as in newly-obtained sequence data for additional populations. We find that all non-African populations carry a signature of selection on the same haplotype at the TRPV6 locus. The selective footprints, however, are significantly differentiated between non-African populations and estimated to be younger than an ancestral population of non-Africans. The possibility of a single selection event occurring in an ancestral population of non-Africans was tested by simulations and rejected. The putatively-selected TRPV6 haplotype contains three candidate sites for functional differences, namely derived non-synonymous substitutions C157R, M378V and M681T. Potential functional differences between the ancestral and derived TRPV6 proteins were investigated by cloning the ancestral and derived forms, transfecting cell lines, and carrying out electrophysiology experiments via patch clamp analysis. No statistically-significant differences in biophysical channel function were found, although one property of the protein, namely Ca(2+) dependent inactivation, may show functionally relevant differences between the ancestral and derived forms. Although the reason for selection on this locus remains elusive, this is the first demonstration of a widespread parallel selection event acting on standing genetic variation in humans, and highlights the utility of between population EHH statistics.

Parallel selection on TRPV6 in human populations.

Directory of Open Access Journals (Sweden)

David A Hughes

Full Text Available We identified and examined a candidate gene for local directional selection in Europeans, TRPV6, and conclude that selection has acted on standing genetic variation at this locus, creating parallel soft sweep events in humans. A novel modification of the extended haplotype homozygosity (EHH test was utilized, which compares EHH for a single allele across populations, to investigate the signature of selection at TRPV6 and neighboring linked loci in published data sets for Europeans, Asians and African-Americans, as well as in newly-obtained sequence data for additional populations. We find that all non-African populations carry a signature of selection on the same haplotype at the TRPV6 locus. The selective footprints, however, are significantly differentiated between non-African populations and estimated to be younger than an ancestral population of non-Africans. The possibility of a single selection event occurring in an ancestral population of non-Africans was tested by simulations and rejected. The putatively-selected TRPV6 haplotype contains three candidate sites for functional differences, namely derived non-synonymous substitutions C157R, M378V and M681T. Potential functional differences between the ancestral and derived TRPV6 proteins were investigated by cloning the ancestral and derived forms, transfecting cell lines, and carrying out electrophysiology experiments via patch clamp analysis. No statistically-significant differences in biophysical channel function were found, although one property of the protein, namely Ca(2+ dependent inactivation, may show functionally relevant differences between the ancestral and derived forms. Although the reason for selection on this locus remains elusive, this is the first demonstration of a widespread parallel selection event acting on standing genetic variation in humans, and highlights the utility of between population EHH statistics.

Fitness and body composition profiling of elite junior South African ...

African Journals Online (AJOL)

Objective. The aim of this study was to describe the body composition, strength and speed characteristics of elite junior South African rugby players. Design. Cross-sectional. Setting. Field study. Subjects. Rugby players (16 and 18 years old, N = 174) selected for the South African Rugby Union National Green Squad.

Signatures of selection for environmental adaptation and zebu × taurine hybrid fitness in East African shorthorn zebu

Science.gov (United States)

The East African Shorthorn Zebu (EASZ) cattle are ancient hybrid between Asian zebu × African taurine cattle preferred by local farmers due to their adaptability to the African environment. The genetic controls of these adaptabilities are not clearly understood yet. Here, we genotyped 92 EASZ sample...

Materials selection for oxide-based resistive random access memories

International Nuclear Information System (INIS)

Guo, Yuzheng; Robertson, John

2014-01-01

The energies of atomic processes in resistive random access memories (RRAMs) are calculated for four typical oxides, HfO 2 , TiO 2 , Ta 2 O 5 , and Al 2 O 3 , to define a materials selection process. O vacancies have the lowest defect formation energy in the O-poor limit and dominate the processes. A band diagram defines the operating Fermi energy and O chemical potential range. It is shown how the scavenger metal can be used to vary the O vacancy formation energy, via controlling the O chemical potential, and the mean Fermi energy. The high endurance of Ta 2 O 5 RRAM is related to its more stable amorphous phase and the adaptive lattice rearrangements of its O vacancy

Analysis of the genetic diversity of selected East African sweet potato

African Journals Online (AJOL)

Aghomotsegin

Taiwan. Orange. 65. Mugande x New kawogo 2. Uganda. Cream. 66. Bungoma. Uganda .... African countries is still very slow due to financial and technical .... IPGRI, Rome,. Italy and Institute for Genetic Diversity, Ithaca, New York, USA. ISBN:.

African Journals Online: Central African Republic

African Journals Online (AJOL)

African Journals Online: Central African Republic. Home > African Journals Online: Central African Republic. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Browse By Category · Browse Alphabetically · Browse By Country · List All Titles · Free to read Titles This ...

Emergence of multilevel selection in the prisoner's dilemma game on coevolving random networks

International Nuclear Information System (INIS)

Szolnoki, Attila; Perc, Matjaz

2009-01-01

We study the evolution of cooperation in the prisoner's dilemma game, whereby a coevolutionary rule is introduced that molds the random topology of the interaction network in two ways. First, existing links are deleted whenever a player adopts a new strategy or its degree exceeds a threshold value; second, new links are added randomly after a given number of game iterations. These coevolutionary processes correspond to the generic formation of new links and deletion of existing links that, especially in human societies, appear frequently as a consequence of ongoing socialization, change of lifestyle or death. Due to the counteraction of deletions and additions of links the initial heterogeneity of the interaction network is qualitatively preserved, and thus cannot be held responsible for the observed promotion of cooperation. Indeed, the coevolutionary rule evokes the spontaneous emergence of a powerful multilevel selection mechanism, which despite the sustained random topology of the evolving network, maintains cooperation across the whole span of defection temptation values.

Assessing the accuracy and stability of variable selection methods for random forest modeling in ecology

Science.gov (United States)

Random forest (RF) modeling has emerged as an important statistical learning method in ecology due to its exceptional predictive performance. However, for large and complex ecological datasets there is limited guidance on variable selection methods for RF modeling. Typically, e...

Optimization of the Dutch Matrix Test by Random Selection of Sentences From a Preselected Subset

Directory of Open Access Journals (Sweden)

Rolph Houben

2015-04-01

Full Text Available Matrix tests are available for speech recognition testing in many languages. For an accurate measurement, a steep psychometric function of the speech materials is required. For existing tests, it would be beneficial if it were possible to further optimize the available materials by increasing the function’s steepness. The objective is to show if the steepness of the psychometric function of an existing matrix test can be increased by selecting a homogeneous subset of recordings with the steepest sentence-based psychometric functions. We took data from a previous multicenter evaluation of the Dutch matrix test (45 normal-hearing listeners. Based on half of the data set, first the sentences (140 out of 311 with a similar speech reception threshold and with the steepest psychometric function (≥9.7%/dB were selected. Subsequently, the steepness of the psychometric function for this selection was calculated from the remaining (unused second half of the data set. The calculation showed that the slope increased from 10.2%/dB to 13.7%/dB. The resulting subset did not allow the construction of enough balanced test lists. Therefore, the measurement procedure was changed to randomly select the sentences during testing. Random selection may interfere with a representative occurrence of phonemes. However, in our material, the median phonemic occurrence remained close to that of the original test. This finding indicates that phonemic occurrence is not a critical factor. The work highlights the possibility that existing speech tests might be improved by selecting sentences with a steep psychometric function.

Is Africa’s current growth reducing inequality? Evidence from some selected african countries

Directory of Open Access Journals (Sweden)

Alege P.O.

2015-06-01

Full Text Available Is Africa’s current growth reducing inequality? What are the implications of growth on output performances in Africa? Does the effect of Africa’s growth on sectorial output have any implication for inequality in Africa? The study investigates the effect of shocks on a set of macroeconomic variables on inequality (measured by life expectancy and the implication of this on sectors that are perceived to provide economic empowerment in form of employment for people living in the African countries in our sample. Studies already find that growth in many African countries has not been accompanied with significant improvement in employment. Therefore inequality is subject to a counter cyclical trend in production levels when export destination countries experience a recession. The study also provides insight on the effect of growth on sectorial output for three major sectors in the African economy with the intent of analyzing the impact of growth on sectorial development. The method used in this study is Panel Vector Autoregressive (PVAR estimation and the obvious advantage of this method lies in the fact that it allows us to capture both static and dynamic interdependencies and to treat the links across units in an unrestricted fashion. Data is obtained from World Bank (WDI Statistics for the period 1985 to 2012 (28 years for 10 African Countries. Our main findings confirm strong negative relationship between GDP growth and life expectancy and also for GDP and the services and manufacturing sector considering the full sample.

The Cancer Pattern in African Gold Miners†

Science.gov (United States)

Robertson, M. A.; Harington, J. S.; Bradshaw, Evelyn

1971-01-01

The incidence of cancer among the African workers on the gold mines of South Africa has been studied for the period 1964-68. Considering the degree of selection to which they are subjected, the crude cancer rate was unexpectedly high. The most common cancers were those of the liver, the oesophagus, the respiratory system and the bladder. Geographical and tribal analysis showed that both liver and bladder cancers were predominantly found in Africans from Mozambique, while most of the oesophageal cancer occurred in Xhosas from the Transkei. The highest rate for cancer of the respiratory system was found in Africans from Natal, predominantly Zulu. The findings of this survey confirm those of previous South African surveys. The differences in cancer incidence are linked to both geographical area (physical environment), and to tribe, which may mean an association with tribal habit and custom. These factors need further investigation. PMID:5144513

The cancer pattern in African gold miners.

Science.gov (United States)

Robertson, M A; Harington, J S; Bradshaw, E

1971-09-01

The incidence of cancer among the African workers on the gold mines of South Africa has been studied for the period 1964-68. Considering the degree of selection to which they are subjected, the crude cancer rate was unexpectedly high.The most common cancers were those of the liver, the oesophagus, the respiratory system and the bladder. Geographical and tribal analysis showed that both liver and bladder cancers were predominantly found in Africans from Mozambique, while most of the oesophageal cancer occurred in Xhosas from the Transkei. The highest rate for cancer of the respiratory system was found in Africans from Natal, predominantly Zulu.The findings of this survey confirm those of previous South African surveys. The differences in cancer incidence are linked to both geographical area (physical environment), and to tribe, which may mean an association with tribal habit and custom. These factors need further investigation.

Random drift versus selection in academic vocabulary: an evolutionary analysis of published keywords.

Science.gov (United States)

Bentley, R Alexander

2008-08-27

The evolution of vocabulary in academic publishing is characterized via keyword frequencies recorded in the ISI Web of Science citations database. In four distinct case-studies, evolutionary analysis of keyword frequency change through time is compared to a model of random copying used as the null hypothesis, such that selection may be identified against it. The case studies from the physical sciences indicate greater selection in keyword choice than in the social sciences. Similar evolutionary analyses can be applied to a wide range of phenomena; wherever the popularity of multiple items through time has been recorded, as with web searches, or sales of popular music and books, for example.

Parsing the Gulf between Africans and African Americans

Directory of Open Access Journals (Sweden)

Ashly Nsangou

2018-02-01

Full Text Available The rise in African immigrants to the US provides an opportunity to assess relations between Africans and African Americans in college. An online survey of 322 current and recently-graduated college students (including 45 Africans, 160 African Americans, and 117 whites assessed respondents’ experiences of racism in US high schools and colleges. Semi-structured interviews of 30 students (10 African, 10 African American and 10 white students supplemented these data. Even within a sociopolitical context of more visible racial intolerance, Black intra-racial cohesion was absent. Although more first- and second-generation Africans (73% felt that they had been judged while living in the US compared to African Americans (34% or whites (20%, for 70–80% of respondents, this had occurred only in high school. Despite experiencing these judgments, Africans’ identity related more to their focus on education than their race, reflected in a higher proportion who felt intense family pressure to attend college (65% compared to African Americans (37% and whites (39%. Interview data confirmed previous reports in the literature that African Americans lack a sense of connection to Africans, attributed to Africans’ purported sense of superiority and disregard for African Americans’ ongoing struggle to end oppression. These mixed-methods data suggest that intermingling in the college environment has not resulted in first- and second-generation Africans and African Americans sharing a common in-group, race-based identity. We discuss the implications of overlooking ethnic distinctions due to presumptions of racial homogeneity that deprive Black individuals of their uniqueness.

A survey of selected key areas of management of South African ...

African Journals Online (AJOL)

Background: Previous surveys of neurosurgical patient management, including a South African (SA) survey conducted in 2001, confirmed the existence of significant dissimilarities in management on national and international levels. This survey aimed to determine current SA neurosurgical patient management and to ...

Association between smoking cessation and weight gain in treatment-seeking African Americans.

Science.gov (United States)

Tan, Marcia M; Okuyemi, Kolawole S; Resnicow, Ken; Dietz, Noella A; Antoni, Michael H; Webb Hooper, Monica

2018-06-01

Research has shown that African Americans gain more than average weight after smoking cessation. However, African Americans have been underrepresented in post-cessation weight gain research. The current study examined 1) the pattern of weight gain and 2) the association between smoking status and weight gain in a sample of African Americans seeking smoking cessation treatment. Data were drawn from a randomized controlled trial testing the efficacy of a 4-week culturally specific smoking cessation cognitive behavioral therapy (CBT) intervention among African American smokers (N = 342). Weight was measured and self-reported smoking status was biochemically verified at baseline, end of counseling, 3-, 6-, and 12-month follow-ups. Random effects multilevel modeling was used to examine weight gain over twelve months post CBT, and a fully unconditional model tested the pattern of weight gain over time. Smoking status was included as a time-varying factor to examine its effect on weight gain, controlling for potential confounding variables. Weight significantly increased among those who remained abstinent over 12 months post CBT [average gain of seven lbs. (three kg)]. Controlling for covariates, abstinence was predictive of the rate of weight gain for those with high weight concern. Weight gain among African American abstainers was comparable to the average post-cessation weight gain observed among the general population. It is possible that exposure to CBT (culturally specific or standard) may have mitigated excessive weight gain. Future research should assess predictors of weight gain in African American smokers to inform future smoking cessation interventions and help elucidate factors that contribute to tobacco- and obesity-related health disparities. Copyright © 2018 Elsevier Ltd. All rights reserved.

Materials selection for oxide-based resistive random access memories

Energy Technology Data Exchange (ETDEWEB)

Guo, Yuzheng; Robertson, John [Engineering Department, Cambridge University, Cambridge CB2 1PZ (United Kingdom)

2014-12-01

The energies of atomic processes in resistive random access memories (RRAMs) are calculated for four typical oxides, HfO{sub 2}, TiO{sub 2}, Ta{sub 2}O{sub 5}, and Al{sub 2}O{sub 3}, to define a materials selection process. O vacancies have the lowest defect formation energy in the O-poor limit and dominate the processes. A band diagram defines the operating Fermi energy and O chemical potential range. It is shown how the scavenger metal can be used to vary the O vacancy formation energy, via controlling the O chemical potential, and the mean Fermi energy. The high endurance of Ta{sub 2}O{sub 5} RRAM is related to its more stable amorphous phase and the adaptive lattice rearrangements of its O vacancy.

Review of Southern African Studies

African Journals Online (AJOL)

Review of Southern African Studies is a multidisciplinary journal of Arts, Social and Behavioural Sciences. Vol 13, No 1 (2009). DOWNLOAD FULL TEXT Open Access DOWNLOAD FULL TEXT Subscription or Fee Access. Table of Contents. Articles. Health-Care Waste Practices in Selected Health-Care Facilities in Maseru ...

Pilot Recruitment of African-Americans: An Examinaton of a Negative Trend

National Research Council Canada - National Science Library

Kaufman, Christopher

2000-01-01

...). The criteria used to select pilot training candidates from eligible AFROTC students were carefully examined to identify factors in the selection process that potentially limit the number of African...

African Journals Online: African Studies

African Journals Online (AJOL)

Items 51 - 56 of 56 ... Research Review of the Institute of African Studies. Please note: As of 2013 the Research Review of the Institute of African Studies is now publishing under the title Contemporary Journal of African Studies. You can view the CJAS pages on AJOL here: http://www.ajol.info/index.php/contjas/index.

Black versus Black: The Relationship among African, African American, and African Caribbean Persons.

Science.gov (United States)

Jackson, Jennifer V.; Cothran, Mary E.

2003-01-01

Surveyed people of African descent regarding relationships among African, African-American, and African-Caribbean persons, focusing on contact and friendship, travel to countries of the diaspora, cross-cultural communication, thoughts and stereotypes, and education. Most respondents had contacts with the other groups, but groups had preconceived…

Non specific immune response in the African catfish ...

African Journals Online (AJOL)

Non specific immune response in the African catfish, Heterobranchus longifilis fed diets fortified with ethanolic extracts of selected traditional medicinal plants and disease resistance against Pseudomonas aeruginosa.

40 CFR 761.306 - Sampling 1 meter square surfaces by random selection of halves.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sampling 1 meter square surfaces by...(b)(3) § 761.306 Sampling 1 meter square surfaces by random selection of halves. (a) Divide each 1 meter square portion where it is necessary to collect a surface wipe test sample into two equal (or as...

"Girls Hit!" Constructing and Negotiating Violent African Femininities in a Working-Class Primary School

Science.gov (United States)

Bhana, Deevia

2008-01-01

Whenever gender violence and schooling have been the topic of South African research, the investigations focus on African boys in secondary schools. In contrast, this paper focuses on the ways in which violence is mobilized by African schoolgirls in a working-class primary school context. By drawing on selected elements of an ethnographic study of…

Flow-gauging structures in South African rivers Part 1: An overview ...

African Journals Online (AJOL)

provided on the different structures will assist the reader with the selection of an appropriate structure. The historical development of the gauging structure network in South African rivers is briefly discussed. Gauging structures used in South African rivers and basic design criteria for the preferred structures at this stage, ...

From Protocols to Publications: A Study in Selective Reporting of Outcomes in Randomized Trials in Oncology

Science.gov (United States)

Raghav, Kanwal Pratap Singh; Mahajan, Sminil; Yao, James C.; Hobbs, Brian P.; Berry, Donald A.; Pentz, Rebecca D.; Tam, Alda; Hong, Waun K.; Ellis, Lee M.; Abbruzzese, James; Overman, Michael J.

2015-01-01

Purpose The decision by journals to append protocols to published reports of randomized trials was a landmark event in clinical trial reporting. However, limited information is available on how this initiative effected transparency and selective reporting of clinical trial data. Methods We analyzed 74 oncology-based randomized trials published in Journal of Clinical Oncology, the New England Journal of Medicine, and The Lancet in 2012. To ascertain integrity of reporting, we compared published reports with their respective appended protocols with regard to primary end points, nonprimary end points, unplanned end points, and unplanned analyses. Results A total of 86 primary end points were reported in 74 randomized trials; nine trials had greater than one primary end point. Nine trials (12.2%) had some discrepancy between their planned and published primary end points. A total of 579 nonprimary end points (median, seven per trial) were planned, of which 373 (64.4%; median, five per trial) were reported. A significant positive correlation was found between the number of planned and nonreported nonprimary end points (Spearman r = 0.66; P < .001). Twenty-eight studies (37.8%) reported a total of 65 unplanned end points; 52 (80.0%) of which were not identified as unplanned. Thirty-one (41.9%) and 19 (25.7%) of 74 trials reported a total of 52 unplanned analyses involving primary end points and 33 unplanned analyses involving nonprimary end points, respectively. Studies reported positive unplanned end points and unplanned analyses more frequently than negative outcomes in abstracts (unplanned end points odds ratio, 6.8; P = .002; unplanned analyses odd ratio, 8.4; P = .007). Conclusion Despite public and reviewer access to protocols, selective outcome reporting persists and is a major concern in the reporting of randomized clinical trials. To foster credible evidence-based medicine, additional initiatives are needed to minimize selective reporting. PMID:26304898

Joint random beam and spectrum selection for spectrum sharing systems with partial channel state information

KAUST Repository

Abdallah, Mohamed M.

2013-11-01

In this work, we develop joint interference-aware random beam and spectrum selection scheme that provide enhanced performance for the secondary network under the condition that the interference observed at the primary receiver is below a predetermined acceptable value. We consider a secondary link composed of a transmitter equipped with multiple antennas and a single-antenna receiver sharing the same spectrum with a set of primary links composed of a single-antenna transmitter and a single-antenna receiver. The proposed schemes jointly select a beam, among a set of power-optimized random beams, as well as the primary spectrum that maximizes the signal-to-interference-plus-noise ratio (SINR) of the secondary link while satisfying the primary interference constraint. In particular, we consider the case where the interference level is described by a q-bit description of its magnitude, whereby we propose a technique to find the optimal quantizer thresholds in a mean square error (MSE) sense. © 2013 IEEE.

Joint random beam and spectrum selection for spectrum sharing systems with partial channel state information

KAUST Repository

Abdallah, Mohamed M.; Sayed, Mostafa M.; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

2013-01-01

In this work, we develop joint interference-aware random beam and spectrum selection scheme that provide enhanced performance for the secondary network under the condition that the interference observed at the primary receiver is below a predetermined acceptable value. We consider a secondary link composed of a transmitter equipped with multiple antennas and a single-antenna receiver sharing the same spectrum with a set of primary links composed of a single-antenna transmitter and a single-antenna receiver. The proposed schemes jointly select a beam, among a set of power-optimized random beams, as well as the primary spectrum that maximizes the signal-to-interference-plus-noise ratio (SINR) of the secondary link while satisfying the primary interference constraint. In particular, we consider the case where the interference level is described by a q-bit description of its magnitude, whereby we propose a technique to find the optimal quantizer thresholds in a mean square error (MSE) sense. © 2013 IEEE.

The RANDOM computer program: A linear congruential random number generator

Science.gov (United States)

Miles, R. F., Jr.

1986-01-01

The RANDOM Computer Program is a FORTRAN program for generating random number sequences and testing linear congruential random number generators (LCGs). The linear congruential form of random number generator is discussed, and the selection of parameters of an LCG for a microcomputer described. This document describes the following: (1) The RANDOM Computer Program; (2) RANDOM.MOD, the computer code needed to implement an LCG in a FORTRAN program; and (3) The RANCYCLE and the ARITH Computer Programs that provide computational assistance in the selection of parameters for an LCG. The RANDOM, RANCYCLE, and ARITH Computer Programs are written in Microsoft FORTRAN for the IBM PC microcomputer and its compatibles. With only minor modifications, the RANDOM Computer Program and its LCG can be run on most micromputers or mainframe computers.

Analysis and applications of a frequency selective surface via a random distribution method

International Nuclear Information System (INIS)

Xie Shao-Yi; Huang Jing-Jian; Yuan Nai-Chang; Liu Li-Guo

2014-01-01

A novel frequency selective surface (FSS) for reducing radar cross section (RCS) is proposed in this paper. This FSS is based on the random distribution method, so it can be called random surface. In this paper, the stacked patches serving as periodic elements are employed for RCS reduction. Previous work has demonstrated the efficiency by utilizing the microstrip patches, especially for the reflectarray. First, the relevant theory of the method is described. Then a sample of a three-layer variable-sized stacked patch random surface with a dimension of 260 mm×260 mm is simulated, fabricated, and measured in order to demonstrate the validity of the proposed design. For the normal incidence, the 8-dB RCS reduction can be achieved both by the simulation and the measurement in 8 GHz–13 GHz. The oblique incidence of 30° is also investigated, in which the 7-dB RCS reduction can be obtained in a frequency range of 8 GHz–14 GHz. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Random drift versus selection in academic vocabulary: an evolutionary analysis of published keywords.

Directory of Open Access Journals (Sweden)

R Alexander Bentley

Full Text Available The evolution of vocabulary in academic publishing is characterized via keyword frequencies recorded in the ISI Web of Science citations database. In four distinct case-studies, evolutionary analysis of keyword frequency change through time is compared to a model of random copying used as the null hypothesis, such that selection may be identified against it. The case studies from the physical sciences indicate greater selection in keyword choice than in the social sciences. Similar evolutionary analyses can be applied to a wide range of phenomena; wherever the popularity of multiple items through time has been recorded, as with web searches, or sales of popular music and books, for example.

On theoretical models of gene expression evolution with random genetic drift and natural selection.

Directory of Open Access Journals (Sweden)

Osamu Ogasawara

2009-11-01

Full Text Available The relative contributions of natural selection and random genetic drift are a major source of debate in the study of gene expression evolution, which is hypothesized to serve as a bridge from molecular to phenotypic evolution. It has been suggested that the conflict between views is caused by the lack of a definite model of the neutral hypothesis, which can describe the long-run behavior of evolutionary change in mRNA abundance. Therefore previous studies have used inadequate analogies with the neutral prediction of other phenomena, such as amino acid or nucleotide sequence evolution, as the null hypothesis of their statistical inference.In this study, we introduced two novel theoretical models, one based on neutral drift and the other assuming natural selection, by focusing on a common property of the distribution of mRNA abundance among a variety of eukaryotic cells, which reflects the result of long-term evolution. Our results demonstrated that (1 our models can reproduce two independently found phenomena simultaneously: the time development of gene expression divergence and Zipf's law of the transcriptome; (2 cytological constraints can be explicitly formulated to describe long-term evolution; (3 the model assuming that natural selection optimized relative mRNA abundance was more consistent with previously published observations than the model of optimized absolute mRNA abundances.The models introduced in this study give a formulation of evolutionary change in the mRNA abundance of each gene as a stochastic process, on the basis of previously published observations. This model provides a foundation for interpreting observed data in studies of gene expression evolution, including identifying an adequate time scale for discriminating the effect of natural selection from that of random genetic drift of selectively neutral variations.

From Protocols to Publications: A Study in Selective Reporting of Outcomes in Randomized Trials in Oncology.

Science.gov (United States)

Raghav, Kanwal Pratap Singh; Mahajan, Sminil; Yao, James C; Hobbs, Brian P; Berry, Donald A; Pentz, Rebecca D; Tam, Alda; Hong, Waun K; Ellis, Lee M; Abbruzzese, James; Overman, Michael J

2015-11-01

The decision by journals to append protocols to published reports of randomized trials was a landmark event in clinical trial reporting. However, limited information is available on how this initiative effected transparency and selective reporting of clinical trial data. We analyzed 74 oncology-based randomized trials published in Journal of Clinical Oncology, the New England Journal of Medicine, and The Lancet in 2012. To ascertain integrity of reporting, we compared published reports with their respective appended protocols with regard to primary end points, nonprimary end points, unplanned end points, and unplanned analyses. A total of 86 primary end points were reported in 74 randomized trials; nine trials had greater than one primary end point. Nine trials (12.2%) had some discrepancy between their planned and published primary end points. A total of 579 nonprimary end points (median, seven per trial) were planned, of which 373 (64.4%; median, five per trial) were reported. A significant positive correlation was found between the number of planned and nonreported nonprimary end points (Spearman r = 0.66; P medicine, additional initiatives are needed to minimize selective reporting. © 2015 by American Society of Clinical Oncology.

Prenatal care of African American women in selected USA urban and rural cultural contexts.

Science.gov (United States)

Morgan, M

1996-01-01

The purpose of this ethnonursing research was to systematically discover, describe, and analyze the beliefs, practices, and values of African American women related to prenatal care. The domain of inquiry was prenatal care of African American women within their familiar cultural contexts. The study was conceptualized within Leininger's Theory of Culture Care Diversity and Universality which enabled the researcher to study professional and generic care as influenced by the worldview, social structural factors, cultural values and beliefs, ethnohistory, and environmental context. The goal of the study was to discover knowledge that could be used by health professionals to provide culturally congruent prenatal care that would increase the health and well being of the people. The rationale for the study was based on studies that showed the lack of prenatal care in the African American cultural group leads to low birth weights and high infant mortality rates. Four major themes that focused on the domain of inquiry were identified: 1) Cultural care meant protection, presence, and sharing; 2) social structural factors that greatly influenced the health and well being were spirituality, kinship, and economics; 3) professional prenatal care was seen by the women as necessary and essential but there was distrust of noncaring professionals, and barriers to such care; and 4) folk health beliefs, practices, and indigenous health care providers were widely used by women in the African American community.

Darwin’s legacy in South African evolutionary biology

Directory of Open Access Journals (Sweden)

S. D. Johnson

2010-02-01

Full Text Available In the two decades after publication of the Origin of Species, Charles Darwin facilitated the publication of numerous scientific papers by settler naturalists in South Africa. This helped to establish the strong tradition of natural history which has characterised evolutionary research in South African museums, herbaria and universities. Significant developments in the early 20th century included the hominid fossil discoveries of Raymond Dart, Robert Broom, and others, but there was otherwise very little South African involvement in the evolutionary synthesis of the 1930s and 1940s. Evolutionary biology developed into a distinct discipline in South Africa during the 1970s and 1980s when it was dominated by mammalian palaeontology and a vigorous debate around species concepts. In the post-apartheid era, the main focus of evolutionary biology has been the construction of phylogenies for African plants and animals using molecular data, and the use of these phylogenies to answer questions about taxonomic classification and trait evolution. South African biologists have also recently contributed important evidence for some of Darwin’s ideas about plant–animal coevolution, sexual selection, and the role of natural selection in speciation. A bibliographic analysis shows that South African authors produce 2–3% of the world’s publications in the field of evolutionary biology, which is much higher than the value of about 0.5% for publications in all sciences. With its extraordinary biodiversity and well-developed research infrastructure, South Africa is an ideal laboratory from which to advance evolutionary research.

A Mainly Circum-Mediterranean Origin for West Eurasian and North African mtDNAs in Puerto Rico with Strong Contributions from the Canary Islands and West Africa.

Science.gov (United States)

Díaz-Zabala, Héctor J; Nieves-Colón, María A; Martínez-Cruzado, Juan C

2017-04-01

Maternal lineages of West Eurasian and North African origin account for 11.5% of total mitochondrial ancestry in Puerto Rico. Historical sources suggest that this ancestry arrived mostly from European migrations that took place during the four centuries of the Spanish colonization of Puerto Rico. This study analyzed 101 mitochondrial control region sequences and diagnostic coding region variants from a sample set randomly and systematically selected using a census-based sampling frame to be representative of the Puerto Rican population, with the goal of defining West Eurasian-North African maternal clades and estimating their possible geographical origin. Median-joining haplotype networks were constructed using hypervariable regions 1 and 2 sequences from various reference populations in search of shared haplotypes. A posterior probability analysis was performed to estimate the percentage of possible origins across wide geographic regions for the entire sample set and for the most common haplogroups on the island. Principal component analyses were conducted to place the Puerto Rican mtDNA set within the variation present among all reference populations. Our study shows that up to 38% of West Eurasian and North African mitochondrial ancestry in Puerto Rico most likely migrated from the Canary Islands. However, most of those haplotypes had previously migrated to the Canary Islands from elsewhere, and there are substantial contributions from various populations across the circum-Mediterranean region and from West African populations related to the modern Wolof and Serer peoples from Senegal and the nomad Fulani who extend up to Cameroon. In conclusion, the West Eurasian mitochondrial ancestry in Puerto Ricans is geographically diverse. However, haplotype diversity seems to be low, and frequencies have been shaped by population bottlenecks, migration waves, and random genetic drift. Consequently, approximately 47% of mtDNAs of West Eurasian and North African ancestry

THE SAVINGS-TRADE-FISCAL GAP MODEL: APPLICATION IN SELECTED WEST AFRICAN STATES

Directory of Open Access Journals (Sweden)

Efayena Oba Obukohwo

2017-07-01

Full Text Available With most African economies experiencing adverse economic misalignment in recent times, the need of enhancing the growth process cannot be overemphasized. Using a typical Savings-Trade-Fiscal Gap Model, the paper employed panel data estimation method to examine the impact of savings, trade and fiscal gap on economic growth of 15 West African countries. The paper finds a negative relationship between net trade and economic growth, while savings and government expenditure impacts positively on economic performance. The paper thus, among recommended that it is appropriate for all countries to eliminate fiscal dominance from monetary policy-making, reduce public debt and establish institutions that promote and encourage counter-cyclical fiscal policy, develop their financial systems, establish credibility in fiscal and monetary policy-making as well as encourage trade.

Measuring Financial Literacy: Developing and Testing a Measurement Instrument with a Selected Group of South African Military Officers

Science.gov (United States)

Schwella, E.; van Nieuwenhuyzen, Bernard J.

2014-01-01

Are South Africans financially literate, and how can this be measured? Until 2009 there was no South African financial literacy measure and, therefore, the aim was to develop a South African measurement instrument that is scientific, socially acceptable, valid and reliable. To achieve this aim a contextual and conceptual analysis of financial…

Nutrient digestibility and nitrogen metabolism in West African dwarf ...

African Journals Online (AJOL)

An experiment was conducted to determine nutrient digestibility and nitrogen metabolism in sheep fed differently processed breadfruit meal. Twenty West African dwarf sheep with mean weight body of 6.00 ± 0.55kg were randomly allotted to four dietary treatments with five sheep per treatment in a completely randomised ...

Relationship power, communication, and violence among couples: results of a cluster-randomized HIV prevention study in a South African township

Directory of Open Access Journals (Sweden)

Minnis AM

2015-05-01

Full Text Available Alexandra M Minnis,1,2 Irene A Doherty,1,3 Tracy L Kline,1 William A Zule,1 Bronwyn Myers,4,5 Tara Carney,4 Wendee M Wechsberg1,3,6,7 1RTI International, Research Triangle Park, NC, 2School of Public Health, University of California, Berkeley, CA, 3University of North Carolina, Chapel Hill, NC, USA; 4Alcohol, Tobacco and Other Drug Research Unit, South African Medical Research Council, 5Department of Psychiatry and Mental Health, University of Cape Town, Cape Town, South Africa; 6North Carolina State University, Raleigh, 7Duke University School of Medicine, Durham, NC, USA Background: Inequitable gender-based power in relationships and intimate partner violence contribute to persistently high rates of HIV infection among South African women. We examined the effects of two group-based HIV prevention interventions that engaged men and their female partners together in a couples intervention (Couples Health CoOp [CHC] and a gender-separate intervention (Men’s Health CoOp/Women’s Health CoOp [MHC/WHC] on women’s reports of power, communication, and conflict in relationships. Methods: The cluster-randomized field experiment included heterosexual couples from a high-density South African township in which neighborhoods were randomized to one of the intervention arms or a control arm that received the WHC only. Participants completed in-person study visits at baseline and 6-month follow-up. We examined group differences using one-way analysis of variance and multivariable regression models.Results: Of the 290 couples enrolled, 255 women remained in the same partnership over 6 months. Following the intervention, women in the CHC arm compared with those in the WHC arm were more likely to report an increase in relationship control (ß=0.92, 95% confidence interval [CI]: 0.02, 1.83, P=0.045 and gender norms supporting female autonomy in relationships (ß=0.99, 95% CI: 0.07, 1.91, P=0.035. Women in the MHC/WHC arm were more likely to report increases

Characteristics of soils in selected maize growing sites along altitudinal gradients in East African highlands

Directory of Open Access Journals (Sweden)

Elijah Njuguna

2015-12-01

Full Text Available Maize is the main staple crop in the East African Mountains. Understanding how the edaphic characteristics change along altitudinal gradients is important for maximizing maize production in East African Highlands, which are the key maize production areas in the region. This study evaluated and compared the levels of some macro and micro-elements (Al, Ca, Fe, K, Mg, Mn, Na and P and other soil parameters (pH, organic carbon content, soil texture [i.e. % Sand, % Clay and % Silt], cation exchange capacity [CEC], electric conductivity [EC], and water holding capacity [HC]. Soil samples were taken from maize plots along three altitudinal gradients in East African highlands (namely Machakos Hills, Taita Hills and Mount Kilimanjaro characterized by graded changes in climatic conditions. For all transects, pH, Ca, K and Mg decreased with the increase in altitude. In contrast, % Silt, organic carbon content, Al and water holding capacity (HC increased with increasing altitude. The research provides information on the status of the physical–chemical characteristics of soils along three altitudinal ranges of East African Highlands and includes data available for further research.

High Entropy Random Selection Protocols

NARCIS (Netherlands)

H. Buhrman (Harry); M. Christandl (Matthias); M. Koucky (Michal); Z. Lotker (Zvi); B. Patt-Shamir; M. Charikar; K. Jansen; O. Reingold; J. Rolim

2007-01-01

textabstractIn this paper, we construct protocols for two parties that do not trust each other, to generate random variables with high Shannon entropy. We improve known bounds for the trade off between the number of rounds, length of communication and the entropy of the outcome.

Health expenditure and economic growth - a review of the literature and an analysis between the economic community for central African states (CEMAC) and selected African countries.

Science.gov (United States)

Piabuo, Serge Mandiefe; Tieguhong, Julius Chupezi

2017-12-01

African leaders accepted in the year 2001 through the Abuja Declaration to allocate 15% of their government expenditure on health but by 2013 only five (5) African countries achieved this target. In this paper, a comparative analysis on the impact of health expenditure between countries in the CEMAC sub-region and five other African countries that achieved the Abuja declaration is provided. Data for this study was extracted from the World Development Indicators (2016) database, panel ordinary least square (OLS), fully modified ordinary least square (FMOLS) and dynamic ordinary least square (DOLS) were used as econometric technic of analysis. Results showed that health expenditure has a positive and significant effect on economic growth in both samples. A unit change in health expenditure can potentially increase GDP per capita by 0.38 and 0.3 units for the five other African countries that achieve the Abuja target and for CEMAC countries respectively, a significant difference of 0.08 units among the two samples. In addition, a long-run relationship also exist between health expenditure and economic growth for both groups of countries. Thus African Economies are strongly advised to achieve the Abuja target especially when other socio-economic and political factors are efficient.

Technological pedagogical content knowledge in South African mathematics classrooms: A secondary analysis of SITES 2006 data

Directory of Open Access Journals (Sweden)

Verona Leendertz

2013-12-01

Full Text Available This article reports on a secondary data analysis conducted on the South African mathematics teachers’ dataset of the Second Information Technology in Education Study (SITES 2006. The sample consisted of a stratified sample of 640 mathematics teachers from 504 randomly selected computer-using and non–computer-using schools that completed the SITES 2006 teachers’ questionnaire, which investigated their pedagogical use of Information Communication Technology (ICT. The purpose of the current investigation was to investigate the level of Technological Pedagogical Content Knowledge (TPACK of mathematics teachers, and how TPACK attributes contribute towards more effective Grade 8 mathematics teaching in South African schools, using the TPACK conceptual framework. The findings are presented according to the three clusters identified through the association between the main variables of the TPACK model and other variables on the SITES 2006 teachers’ questionnaire: (1 impact of ICT use, (2 teacher practices and (3 barriers. A Cramér V of between 0.3 and 0.4 was considered to signal a medium effect that tended towards practically significant association, and a Cramér V of 0.4 or larger was considered to signal a large effect with practically significant association. The results indicate that the TPACK of mathematics teachers contributes towards more effective Grade 8 mathematics teaching in South African schools.

Integrated Behavior Therapy for Selective Mutism: a randomized controlled pilot study.

Science.gov (United States)

Bergman, R Lindsey; Gonzalez, Araceli; Piacentini, John; Keller, Melody L

2013-10-01

To evaluate the feasibility, acceptability, and preliminary efficacy of a novel behavioral intervention for reducing symptoms of selective mutism and increasing functional speech. A total of 21 children ages 4 to 8 with primary selective mutism were randomized to 24 weeks of Integrated Behavior Therapy for Selective Mutism (IBTSM) or a 12-week Waitlist control. Clinical outcomes were assessed using blind independent evaluators, parent-, and teacher-report, and an objective behavioral measure. Treatment recipients completed a three-month follow-up to assess durability of treatment gains. Data indicated increased functional speaking behavior post-treatment as rated by parents and teachers, with a high rate of treatment responders as rated by blind independent evaluators (75%). Conversely, children in the Waitlist comparison group did not experience significant improvements in speaking behaviors. Children who received IBTSM also demonstrated significant improvements in number of words spoken at school compared to baseline, however, significant group differences did not emerge. Treatment recipients also experienced significant reductions in social anxiety per parent, but not teacher, report. Clinical gains were maintained over 3 month follow-up. IBTSM appears to be a promising new intervention that is efficacious in increasing functional speaking behaviors, feasible, and acceptable to parents and teachers. Copyright © 2013 Elsevier Ltd. All rights reserved.

Field-based random sampling without a sampling frame: control selection for a case-control study in rural Africa.

Science.gov (United States)

Crampin, A C; Mwinuka, V; Malema, S S; Glynn, J R; Fine, P E

2001-01-01

Selection bias, particularly of controls, is common in case-control studies and may materially affect the results. Methods of control selection should be tailored both for the risk factors and disease under investigation and for the population being studied. We present here a control selection method devised for a case-control study of tuberculosis in rural Africa (Karonga, northern Malawi) that selects an age/sex frequency-matched random sample of the population, with a geographical distribution in proportion to the population density. We also present an audit of the selection process, and discuss the potential of this method in other settings.

Treatment selection in a randomized clinical trial via covariate-specific treatment effect curves.

Science.gov (United States)

Ma, Yunbei; Zhou, Xiao-Hua

2017-02-01

For time-to-event data in a randomized clinical trial, we proposed two new methods for selecting an optimal treatment for a patient based on the covariate-specific treatment effect curve, which is used to represent the clinical utility of a predictive biomarker. To select an optimal treatment for a patient with a specific biomarker value, we proposed pointwise confidence intervals for each covariate-specific treatment effect curve and the difference between covariate-specific treatment effect curves of two treatments. Furthermore, to select an optimal treatment for a future biomarker-defined subpopulation of patients, we proposed confidence bands for each covariate-specific treatment effect curve and the difference between each pair of covariate-specific treatment effect curve over a fixed interval of biomarker values. We constructed the confidence bands based on a resampling technique. We also conducted simulation studies to evaluate finite-sample properties of the proposed estimation methods. Finally, we illustrated the application of the proposed method in a real-world data set.

African rainforests: past, present and future

Science.gov (United States)

Malhi, Yadvinder; Adu-Bredu, Stephen; Asare, Rebecca A.; Lewis, Simon L.; Mayaux, Philippe

2013-01-01

The rainforests are the great green heart of Africa, and present a unique combination of ecological, climatic and human interactions. In this synthesis paper, we review the past and present state processes of change in African rainforests, and explore the challenges and opportunities for maintaining a viable future for these biomes. We draw in particular on the insights and new analyses emerging from the Theme Issue on ‘African rainforests: past, present and future’ of Philosophical Transactions of the Royal Society B. A combination of features characterize the African rainforest biome, including a history of climate variation; forest expansion and retreat; a long history of human interaction with the biome; a relatively low plant species diversity but large tree biomass; a historically exceptionally high animal biomass that is now being severely hunted down; the dominance of selective logging; small-scale farming and bushmeat hunting as the major forms of direct human pressure; and, in Central Africa, the particular context of mineral- and oil-driven economies that have resulted in unusually low rates of deforestation and agricultural activity. We conclude by discussing how this combination of factors influences the prospects for African forests in the twenty-first century. PMID:23878339

African rainforests: past, present and future.

Science.gov (United States)

Malhi, Yadvinder; Adu-Bredu, Stephen; Asare, Rebecca A; Lewis, Simon L; Mayaux, Philippe

2013-01-01

The rainforests are the great green heart of Africa, and present a unique combination of ecological, climatic and human interactions. In this synthesis paper, we review the past and present state processes of change in African rainforests, and explore the challenges and opportunities for maintaining a viable future for these biomes. We draw in particular on the insights and new analyses emerging from the Theme Issue on 'African rainforests: past, present and future' of Philosophical Transactions of the Royal Society B. A combination of features characterize the African rainforest biome, including a history of climate variation; forest expansion and retreat; a long history of human interaction with the biome; a relatively low plant species diversity but large tree biomass; a historically exceptionally high animal biomass that is now being severely hunted down; the dominance of selective logging; small-scale farming and bushmeat hunting as the major forms of direct human pressure; and, in Central Africa, the particular context of mineral- and oil-driven economies that have resulted in unusually low rates of deforestation and agricultural activity. We conclude by discussing how this combination of factors influences the prospects for African forests in the twenty-first century.

Human Rights and the African Renaissance | Acheampong | African ...

African Journals Online (AJOL)

This article examines the idea of African renaissance in relation to the teaching of human rights in African schools. It explores the connection between the African Renaissance and human rights, and whether there is a specific African concept of human rights. In the light of these discussions, the article sketches a perspective ...

The heritability of acceptability in South African Merino sheep ...

African Journals Online (AJOL)

Selection for production and reproduction in South African Merino sheep is always combined with selection based on visual appraisal and will, in all probability, remain so for many years to come. Heritabilities for acceptability were estimated using a threshold model to analyse data from two parent Merino studs. Effects ...

SCREENING FOR BOVINE TUBERCULOSIS IN AFRICAN BUFFALO (SYNCERUS CAFFER) IN NGORONGORO CONSERVATION AREA, NORTHERN TANZANIA: IMPLICATIONS FOR PUBLIC HEALTH.

Science.gov (United States)

Katale, Bugwesa Z; Fyumagwa, Robert D; Mjingo, Eblate E; Sayalel, Kuya; Batamuzi, Emmanuel K; Matee, Mecky I; Keyyu, Julius D; Muumba, Justice; Mdaki, Maulid; Mbugi, Erasto V; Rweyemamu, Mark M; Mpanduji, Donald G

2017-10-01

In the Ngorongoro Conservation Area (NCA), Tanzania, where wildlife and livestock interaction is intense, greater potential for intra- and interspecies disease transmission is expected. We assessed the prevalence of bovine tuberculosis in African buffalo (Syncerus caffer) residing on the valley floor of the crater in the NCA. Apparently healthy animals were randomly selected from herds in nine sites of the Ngorongoro Crater. Syncerus caffer buffalo herds were located using very high-frequency radio-aided rangers positioned in various observation points around the crater in the NCA. A total of 102 African buffalo from 16 herds were immobilized from the ground using a cocktail of 4-10 mg etorphine hydrochloride (M99) and 60-150 mg azaperone tartrate. The M99 was reversed using 10-25 mg diprenorphine hydrochloride depending on age of animals. An interferon gamma assay was performed on harvested plasma samples using sandwich enzyme linked immunosorbent assay. Of the 102 animals sampled, two (2%) African buffalo tested positive for bovine tuberculosis. These results corroborate those of the skin test done recently in cattle in the NCA. The presence of bovine tuberculosis in livestock and wildlife suggested the possibility of cross-species transmission of the disease, indicating the need for appropriate intervention measures.

African Journal of Library, Archives and Information Science - Vol 21 ...

African Journals Online (AJOL)

African Journal of Library, Archives and Information Science. ... Mentoring and its Impact on the Publication Output of Librarians in Selected Academic Libraries in South-West Nigeria. F Yusuf, 117-126 ... Role of Information and Communication Technologies in Sustainable Livelihoods in Selected Rural Areas of Tanzania.

The TALKS study to improve communication, logistical, and financial barriers to live donor kidney transplantation in African Americans: protocol of a randomized clinical trial.

Science.gov (United States)

Strigo, Tara S; Ephraim, Patti L; Pounds, Iris; Hill-Briggs, Felicia; Darrell, Linda; Ellis, Matthew; Sudan, Debra; Rabb, Hamid; Segev, Dorry; Wang, Nae-Yuh; Kaiser, Mary; Falkovic, Margaret; Lebov, Jill F; Boulware, L Ebony

2015-10-09

Live donor kidney transplantation (LDKT), an optimal therapy for many patients with end-stage kidney disease, is underutilized, particularly by African Americans. Potential recipient difficulties initiating and sustaining conversations about LDKT, identifying willing and medically eligible donors, and potential donors' logistical and financial hurdles have been cited as potential contributors to race disparities in LDKT. Few interventions specifically targeting these factors have been tested. We report the protocol of the Talking about Living Kidney Donation Support (TALKS) study, a study designed to evaluate the effectiveness of behavioral, educational and financial assistance interventions to improve access to LDKT among African Americans on the deceased donor kidney transplant recipient waiting list. We adapted a previously tested educational and social worker intervention shown to improve consideration and pursuit of LDKT among patients and their family members for its use among patients on the kidney transplant waiting list. We also developed a financial assistance intervention to help potential donors overcome logistical and financial challenges they might face during the pursuit of live kidney donation. We will evaluate the effectiveness of these interventions by conducting a randomized controlled trial in which patients on the deceased donor waiting list receive 1) usual care while on the transplant waiting list, 2) the educational and social worker intervention, or 3) the educational and social worker intervention plus the option of participating in the financial assistance program. The primary outcome of the randomized controlled trial will measure potential recipients' live kidney donor activation (a composite rate of live donor inquiries, completed new live donor evaluations, or live kidney donation) at 1 year. The TALKS study will rigorously assess the effectiveness of promising interventions to reduce race disparities in LDKT. NCT02369354.

Risk and Protective Effects of Sibling Relationships among African American Adolescents

Science.gov (United States)

Soli, Anna R.; McHale, Susan M.; Feinberg, Mark E.

2009-01-01

This study investigated associations between sibling relationships and adjustment among 179 African American adolescent siblings (controlling for family factors) and tested moderating effects of familism values and birth order. Two-level random intercept models revealed that familism values moderated sibling relationship-adjustment linkages,…

Effect of human rotavirus vaccine on severe diarrhea in African infants

OpenAIRE

Madhi, Shabir A; Cunliffe, Nigel A; Steele, Duncan; Witte, Desirée; Kirsten, Mari; Louw, Cheryl; Ngwira, Bagrey; Victor, John C; Gillard, Paul H; Cheuvart, Brigitte B; Han, Htay H; Neuzil, Kathleen M

2016-01-01

: Rotavirus is the most common cause of severe gastroenteritis among young children worldwide. Data are needed to assess the efficacy of the rotavirus vaccine in African children. : We conducted a randomized, placebo-controlled, multicenter trial in South Africa (3166 infants; 64.1% of the total) and Malawi (1773 infants; 35.9% of the total) to evaluate the efficacy of a live, oral rotavirus vaccine in preventing severe rotavirus gastroenteritis. Healthy infants were randomly assigned in a 1:...

The prevalence of body dysmorphic disorder among South African university students

Directory of Open Access Journals (Sweden)

Antonia Dlagnikova

2015-08-01

Full Text Available Background. The prevalence of body dysmorphic disorder (BDD among South African students is explored in this article. BDD is regarded as an obsessive-compulsive-related disorder characterised by a preoccupation with one or more perceived defects or flaws in physical appearance and expressed in repetitive behaviours or mental acts as a response to the appearance concerns, causing clinically significant distress or impairment in functioning.  Objectives. To determine the prevalence of BDD among undergraduate students (N=395 at an inner-city university.  Methods. Proportionate stratified random cluster sampling was used to select the sample. The students completed a demographics survey and the Body Image Disturbance Questionnaire.  Results and conclusion. An overall prevalence rate of 5.1% was found in this study, which is similar to prevalence rates reported in existing literature among student populations. No clinically significant differences in the severity of the BDD were found on the demographic variables of gender, race or sexual orientation. However, students differed significantly in their experience of the severity of the disorder in terms of age, in that students over the age of 21 reported higher severity levels than students under the age of 21. Although the prevalence of the disorder compares with that in other countries, its severity seems to increase with age among South African students.

Selective decontamination in pediatric liver transplants. A randomized prospective study.

Science.gov (United States)

Smith, S D; Jackson, R J; Hannakan, C J; Wadowsky, R M; Tzakis, A G; Rowe, M I

1993-06-01

Although it has been suggested that selective decontamination of the digestive tract (SDD) decreases postoperative aerobic Gram-negative and fungal infections in orthotopic liver transplantation (OLT), no controlled trials exist in pediatric patients. This prospective, randomized controlled study of 36 pediatric OLT patients examines the effect of short-term SDD on postoperative infection and digestive tract flora. Patients were randomized into two groups. The control group received perioperative parenteral antibiotics only. The SDD group received in addition polymyxin E, tobramycin, and amphotericin B enterally and by oropharyngeal swab postoperatively until oral intake was tolerated (6 +/- 4 days). Indications for operation, preoperative status, age, and intensive care unit and hospital length of stay were no different in SDD (n = 18) and control (n = 18) groups. A total of 14 Gram-negative infections (intraabdominal abscess 7, septicemia 5, pneumonia 1, urinary tract 1) developed in the 36 patients studied. Mortality was not significantly different in the two groups. However, there were significantly fewer patients with Gram-negative infections in the SDD group: 3/18 patients (11%) vs. 11/18 patients (50%) in the control group, P < 0.001. There was also significant reduction in aerobic Gram-negative flora in the stool and pharynx in patients receiving SDD. Gram-positive and anaerobic organisms were unaffected. We conclude that short-term postoperative SDD significantly reduces Gram-negative infections in pediatric OLT patients.

Patterns of ancestry, signatures of natural selection, and genetic association with stature in Western African pygmies.

Directory of Open Access Journals (Sweden)

Joseph P Jarvis

Full Text Available African Pygmy groups show a distinctive pattern of phenotypic variation, including short stature, which is thought to reflect past adaptation to a tropical environment. Here, we analyze Illumina 1M SNP array data in three Western Pygmy populations from Cameroon and three neighboring Bantu-speaking agricultural populations with whom they have admixed. We infer genome-wide ancestry, scan for signals of positive selection, and perform targeted genetic association with measured height variation. We identify multiple regions throughout the genome that may have played a role in adaptive evolution, many of which contain loci with roles in growth hormone, insulin, and insulin-like growth factor signaling pathways, as well as immunity and neuroendocrine signaling involved in reproduction and metabolism. The most striking results are found on chromosome 3, which harbors a cluster of selection and association signals between approximately 45 and 60 Mb. This region also includes the positional candidate genes DOCK3, which is known to be associated with height variation in Europeans, and CISH, a negative regulator of cytokine signaling known to inhibit growth hormone-stimulated STAT5 signaling. Finally, pathway analysis for genes near the strongest signals of association with height indicates enrichment for loci involved in insulin and insulin-like growth factor signaling.

Exploring the Learning of Mathematics Word Problems by African Immigrant Early Learners

Science.gov (United States)

Mahofa, Ernest; Adendorff, Stanley; Kwenda, Chiwimbiso

2018-01-01

The aim of this study was to explore the learning of mathematics word problems by African immigrant early learners in the Western Cape Province of South Africa (SA). Phenomenology was used as the philosophical underpinning for this study and also informed the research method. Purposive sampling methods were used to select 10 African immigrant…

Day-ahead load forecast using random forest and expert input selection

International Nuclear Information System (INIS)

Lahouar, A.; Ben Hadj Slama, J.

2015-01-01

Highlights: • A model based on random forests for short term load forecast is proposed. • An expert feature selection is added to refine inputs. • Special attention is paid to customers behavior, load profile and special holidays. • The model is flexible and able to handle complex load signal. • A technical comparison is performed to assess the forecast accuracy. - Abstract: The electrical load forecast is getting more and more important in recent years due to the electricity market deregulation and integration of renewable resources. To overcome the incoming challenges and ensure accurate power prediction for different time horizons, sophisticated intelligent methods are elaborated. Utilization of intelligent forecast algorithms is among main characteristics of smart grids, and is an efficient tool to face uncertainty. Several crucial tasks of power operators such as load dispatch rely on the short term forecast, thus it should be as accurate as possible. To this end, this paper proposes a short term load predictor, able to forecast the next 24 h of load. Using random forest, characterized by immunity to parameter variations and internal cross validation, the model is constructed following an online learning process. The inputs are refined by expert feature selection using a set of if–then rules, in order to include the own user specifications about the country weather or market, and to generalize the forecast ability. The proposed approach is tested through a real historical set from the Tunisian Power Company, and the simulation shows accurate and satisfactory results for one day in advance, with an average error exceeding rarely 2.3%. The model is validated for regular working days and weekends, and special attention is paid to moving holidays, following non Gregorian calendar

A cluster randomized trial of standard quality improvement versus patient-centered interventions to enhance depression care for African Americans in the primary care setting: study protocol NCT00243425

Directory of Open Access Journals (Sweden)

Ghods Bri K

2010-02-01

Full Text Available Abstract Background Several studies document disparities in access to care and quality of care for depression for African Americans. Research suggests that patient attitudes and clinician communication behaviors may contribute to these disparities. Evidence links patient-centered care to improvements in mental health outcomes; therefore, quality improvement interventions that enhance this dimension of care are promising strategies to improve treatment and outcomes of depression among African Americans. This paper describes the design of the BRIDGE (Blacks Receiving Interventions for Depression and Gaining Empowerment Study. The goal of the study is to compare the effectiveness of two interventions for African-American patients with depression--a standard quality improvement program and a patient-centered quality improvement program. The main hypothesis is that patients in the patient-centered group will have a greater reduction in their depression symptoms, higher rates of depression remission, and greater improvements in mental health functioning at six, twelve, and eighteen months than patients in the standard group. The study also examines patient ratings of care and receipt of guideline-concordant treatment for depression. Methods/Design A total of 36 primary care clinicians and 132 of their African-American patients with major depressive disorder were recruited into a cluster randomized trial. The study uses intent-to-treat analyses to compare the effectiveness of standard quality improvement interventions (academic detailing about depression guidelines for clinicians and disease-oriented care management for their patients and patient-centered quality improvement interventions (communication skills training to enhance participatory decision-making for clinicians and care management focused on explanatory models, socio-cultural barriers, and treatment preferences for their patients for improving outcomes over 12 months of follow

Association of pol diversity with antiretroviral treatment outcomes among HIV-infected African children.

Directory of Open Access Journals (Sweden)

Iris Chen

Full Text Available In HIV-infected children, viral diversity tends to increase with age in the absence of antiretroviral treatment (ART. We measured HIV diversity in African children (ages 6-36 months enrolled in a randomized clinical trial comparing two ART regimens (Cohort I of the P1060 trial. Children in this cohort were exposed to single dose nevirapine (sdNVP at birth.HIV diversity was measured retrospectively using a high resolution melting (HRM diversity assay. Samples were obtained from 139 children at the enrollment visit prior to ART initiation. Six regions of the HIV genome were analyzed: two in gag, one in pol, and three in env. A single numeric HRM score that reflects HIV diversity was generated for each region; composite HRM scores were also calculated (mean and median for all six regions.In multivariable median regression models using backwards selection that started with demographic and clinical variables, older age was associated with higher HRM scores (higher HIV diversity in pol (P = 0.005 and with higher mean (P = 0.014 and median (P<0.001 HRM scores. In multivariable models adjusted for age, pre-treatment HIV viral load, pre-treatment CD4%, and randomized treatment regimen, higher HRM scores in pol were associated with shorter time to virologic suppression (P = 0.016 and longer time to study endpoints (virologic failure [VF], VF/death, and VF/off study treatment; P<0.001 for all measures.In this cohort of sdNVP-exposed, ART-naïve African children, higher levels of HIV diversity in the HIV pol region prior to ART initiation were associated with better treatment outcomes.

The African Diaspora in continental African struggles for freedom ...

African Journals Online (AJOL)

In light of this realization, this article discusses the contributions of the African Diaspora towards continental African liberation from European colonial domination, with a view to theorizing the implications of this history on the criticism of African Renaissance literature. Focusing on Diasporan African agency in organizing ...

Adapting hypertension self-management interventions to enhance their sustained effectiveness among urban African Americans.

Science.gov (United States)

Ameling, Jessica M; Ephraim, Patti L; Bone, Lee R; Levine, David M; Roter, Debra L; Wolff, Jennifer L; Hill-Briggs, Felicia; Fitzpatrick, Stephanie L; Noronha, Gary J; Fagan, Peter J; Lewis-Boyer, LaPricia; Hickman, Debra; Simmons, Michelle; Purnell, Leon; Fisher, Annette; Cooper, Lisa A; Aboumatar, Hanan J; Albert, Michael C; Flynn, Sarah J; Boulware, L Ebony

2014-01-01

African Americans suffer disproportionately poor hypertension control despite the availability of efficacious interventions. Using principles of community-based participatory research and implementation science, we adapted established hypertension self-management interventions to enhance interventions' cultural relevance and potential for sustained effectiveness among urban African Americans. We obtained input from patients and their family members, their health care providers, and community members. The process required substantial time and resources, and the adapted interventions will be tested in a randomized controlled trial.

Barriers and Motivators to Reducing Secondhand Smoke Exposure in African American Families of Head Start Children: A Qualitative Study

Science.gov (United States)

Hoehn, Jessica L.; Riekert, Kristin A.; Borrelli, Belinda; Rand, Cynthia S.; Eakin, Michelle N.

2016-01-01

Objective: To identify barriers and motivators for reducing secondhand smoke exposure (SHSe) for families of African-American, low-income, urban children. Method: Audiotaped intervention sessions of 52 African-American caregivers of Head Start children who reported being a smoker and/or had at least one smoker in the home were randomly sampled…

Distribution of orientation selectivity in recurrent networks of spiking neurons with different random topologies.

Science.gov (United States)

Sadeh, Sadra; Rotter, Stefan

2014-01-01

Neurons in the primary visual cortex are more or less selective for the orientation of a light bar used for stimulation. A broad distribution of individual grades of orientation selectivity has in fact been reported in all species. A possible reason for emergence of broad distributions is the recurrent network within which the stimulus is being processed. Here we compute the distribution of orientation selectivity in randomly connected model networks that are equipped with different spatial patterns of connectivity. We show that, for a wide variety of connectivity patterns, a linear theory based on firing rates accurately approximates the outcome of direct numerical simulations of networks of spiking neurons. Distance dependent connectivity in networks with a more biologically realistic structure does not compromise our linear analysis, as long as the linearized dynamics, and hence the uniform asynchronous irregular activity state, remain stable. We conclude that linear mechanisms of stimulus processing are indeed responsible for the emergence of orientation selectivity and its distribution in recurrent networks with functionally heterogeneous synaptic connectivity.

Tipping the balance: use of advergames to promote consumption of nutritious foods and beverages by low-income African American children.

Science.gov (United States)

Pempek, Tiffany A; Calvert, Sandra L

2009-07-01

To examine how advergames, which are online computer games developed to market a product, affect consumption of healthier and less healthy snacks by low-income African American children. Cross-sectional, between-subjects examination of an advergame in which children were rewarded for having their computer character consume healthier or less healthy foods and beverages. Children were randomly assigned to 1 of the following 3 conditions: (1) the healthier advergame condition, (2) the less healthy advergame condition, or (3) the control condition. Urban public elementary schools. Thirty low-income, African American children aged 9 to 10 years. Main Exposure Children in the treatment conditions played a less healthy or a healthier version of an advergame 2 times before choosing and eating a snack and completing the experimental measures. Children in the control group chose and ate a snack before playing the game and completing the measures. The number of healthier snack items children selected and ate and how much children liked the game. Children who played the healthier version of the advergame selected and ate significantly more healthy snacks than did those who played the less healthy version. Children reported liking the advergame. Findings suggest that concerns about online advergames that market unhealthy foods are justified. However, advergames may also be used to promote healthier foods and beverages. This kind of social marketing approach could tip the scales toward the selection of higher-quality snacks, thereby helping to curb the obesity epidemic.

African American Race and Prevalence of Atrial Fibrillation:A Meta-Analysis

Directory of Open Access Journals (Sweden)

Marlow B. Hernandez

2012-01-01

Full Text Available Background. It has been observed that African American race is associated with a lower prevalence of atrial fibrillation (AF compared to Caucasian race. To better quantify the association between African American race and AF, we performed a meta-analysis of published studies among different patient populations which reported the presence of AF by race. Methods. A literature search was conducted using electronic databases between January 1999 and January 2011. The search was limited to published studies in English conducted in the United States, which clearly defined the presence of AF in African American and Caucasian subjects. A meta-analysis was performed with prevalence of AF as the primary endpoint. Results. In total, 10 studies involving 1,031,351 subjects were included. According to a random effects analysis, African American race was associated with a protective effect with regard to AF as compared to Caucasian race (odds ratio 0.51, 95% CI 0.44 to 0.59, <0.001. In subgroup analyses, African American race was significantly associated with a lower prevalence of AF in the general population, those hospitalized or greater than 60 years old, postcoronary artery bypass surgery patients, and subjects with heart failure. Conclusions. In a broad sweep of subjects in the general population and hospitalized patients, the prevalence of AF in African Americans is consistently lower than in Caucasians.

Produção de geléia real com abelhas africanizadas selecionadas e cárnicas híbridas Royal jelly production by selected africanized honeybees and carniolan hybrids

Directory of Open Access Journals (Sweden)

Vagner de Alencar Arnaut de Toledo

2005-12-01

Full Text Available O objetivo foi avaliar a produção de geléia real em colônias de abelhas Apis mellifera, em comparação às africanizadas selecionadas para a produção de geléia real, africanizadas selecionadas para mel com cárnicas híbridas. No experimento I, foram utilizadas 10 colônias de abelhas africanizadas após seleção, para produção de geléia real; as cinco melhores rainhas foram substituídas por suas filhas e, nas restantes, foram introduzidas rainhas cárnicas, para avaliação da produção após troca da população. No experimento II, foram utilizadas 15 colônias, cinco com rainhas africanizadas selecionadas para a produção de mel (AFML, cinco selecionadas para a produção de geléia real (AFGR e cinco cárnicas híbridas (CAHB. No experimento I, as cárnicas híbridas apresentaram maior produção de geléia real/colônia/coleta (3,95 ± 2,92 g que as africanizadas (2,23 ± 2,13 g. As cárnicas foram superiores quanto à porcentagem de aceitação de larvas (55,4 ± 36,7% às africanizadas (35,8 ± 28,3%. Quanto à produção de geléia real/colônia/coleta (g, no experimento II, as abelhas AFML foram significativamente superiores (4,42 ± 2,67 g às CAHB (3,30 ± 1,85 g e às AFGR (3,71 ± 2,13 g, que não diferiram das anteriores. Ambas as africanizadas, AFML e AFGR, produziram mais geléia real por cúpula (254,2 ± 90,7 e 253,8 ± 206,8 g, respectivamente que as CAHB (195,8 ± 80,9 g.This study was conducted to compare royal jelly production from colonies of Apis mellifera Africanized honeybees selected for yields of royal jelly or honey with that from Carniolan hybrids. In the first trial, 10 colonies of Africanized honeybees selected for royal jelly production were used; the top five queens were replaced with their offspring and in the remaining colonies were introduced Carniolan queens in order to evaluate production after switch of population. In the second trial, 15 colonies were used as follows: five with Africanized

Cognitive Distraction and African American Women's Endorsement of Gender Role Stereotypes

Science.gov (United States)

Smith, Kalynda; Craig-Henderson, Kellina

2010-01-01

The present study investigated the effect of cognitive distraction on the endorsement of gender role stereotypes in one sample of African American female participants. Participants' awareness and endorsement of gender role stereotypes for male and females was assessed. Following random assignment to distraction or no distraction conditions, they…

Implementing learnerships: learner recruitment and selection B ...

African Journals Online (AJOL)

Implementing learnerships: learner recruitment and selection B lessons learnt from the KwaZulu-Natal pilot projects. ... 2001 in KwaZulu-Natal, with specific reference to the recruitment and selection of learners. ... AJOL African Journals Online.

In Vitro Activity of Selected West African Medicinal Plants against Mycobacterium ulcerans Disease.

Science.gov (United States)

Tsouh Fokou, Patrick Valere; Kissi-Twum, Abena Adomah; Yeboah-Manu, Dorothy; Appiah-Opong, Regina; Addo, Phyllis; Tchokouaha Yamthe, Lauve Rachel; Ngoutane Mfopa, Alvine; Fekam Boyom, Fabrice; Nyarko, Alexander Kwadwo

2016-04-13

Buruli ulcer (BU) is the third most prevalent mycobacteriosis, after tuberculosis and leprosy. The currently recommended combination of rifampicin-streptomycin suffers from side effects and poor compliance, which leads to reliance on local herbal remedies. The objective of this study was to investigate the antimycobacterial properties and toxicity of selected medicinal plants. Sixty-five extracts from 27 plant species were screened against Mycobacterium ulcerans and Mycobacterium smegmatis, using the Resazurin Microtiter Assay (REMA). The cytotoxicity of promising extracts was assayed on normal Chang liver cells by an MTT assay. Twenty five extracts showed activity with minimal inhibitory concentration (MIC) values ranging from 16 µg/mL to 250 µg/mL against M. smegmatis, while 17 showed activity against M. ulcerans with MIC values ranging from 125 µg/mL to 250 µg/mL. In most of the cases, plant extracts with antimycobacterial activity showed no cytotoxicity on normal human liver cells. Exception were Carica papaya, Cleistopholis patens, and Polyalthia suaveolens with 50% cell cytotoxic concentrations (CC50) ranging from 3.8 to 223 µg/mL. These preliminary results support the use of some West African plants in the treatment of Buruli ulcer. Meanwhile, further studies are required to isolate and characterize the active ingredients in the extracts.

In Vitro Activity of Selected West African Medicinal Plants against Mycobacterium ulcerans Disease

Directory of Open Access Journals (Sweden)

Patrick Valere Tsouh Fokou

2016-04-01

Full Text Available Buruli ulcer (BU is the third most prevalent mycobacteriosis, after tuberculosis and leprosy. The currently recommended combination of rifampicin-streptomycin suffers from side effects and poor compliance, which leads to reliance on local herbal remedies. The objective of this study was to investigate the antimycobacterial properties and toxicity of selected medicinal plants. Sixty-five extracts from 27 plant species were screened against Mycobacterium ulcerans and Mycobacterium smegmatis, using the Resazurin Microtiter Assay (REMA. The cytotoxicity of promising extracts was assayed on normal Chang liver cells by an MTT assay. Twenty five extracts showed activity with minimal inhibitory concentration (MIC values ranging from 16 µg/mL to 250 µg/mL against M. smegmatis, while 17 showed activity against M. ulcerans with MIC values ranging from 125 µg/mL to 250 µg/mL. In most of the cases, plant extracts with antimycobacterial activity showed no cytotoxicity on normal human liver cells. Exception were Carica papaya, Cleistopholis patens, and Polyalthia suaveolens with 50% cell cytotoxic concentrations (CC50 ranging from 3.8 to 223 µg/mL. These preliminary results support the use of some West African plants in the treatment of Buruli ulcer. Meanwhile, further studies are required to isolate and characterize the active ingredients in the extracts.

The African Diaspora, Civil Society and African Integration

DEFF Research Database (Denmark)

Opoku-Mensah, Paul Yaw

This paper, a work-in-progress, makes a contribution to the discussions on the appropriate modalities for incorporating the African diaspora in the African integration project.  It argues that the most appropriate entry points for incorporating the African diaspora into the integration project...... might not, necessarily, be in the formal political structures, although this is important. To the contrary, the most effective and sustainable might be within civil society---that is the links between the peoples and organizations of Africa and the diaspora. Using the case of the African academy......-- as an institution of civil society--- the paper outlines a conceptual framework for incorporating the diaspora into the African integration project....

Evaluation of two vaccine education interventions to improve pertussis vaccination among pregnant African American women: A randomized controlled trial.

Science.gov (United States)

Kriss, Jennifer L; Frew, Paula M; Cortes, Marielysse; Malik, Fauzia A; Chamberlain, Allison T; Seib, Katherine; Flowers, Lisa; Ault, Kevin A; Howards, Penelope P; Orenstein, Walter A; Omer, Saad B

2017-03-13

Vaccination coverage with tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine in pregnancy or immediately postpartum has been low. Limited data exist on rigorously evaluated interventions to increase maternal vaccination, including Tdap. Tailored messaging based on the Elaboration Likelihood Model (ELM) framework has been successful in improving uptake of some public health interventions. We evaluated the effect of two ELM-based vaccine educational interventions on Tdap vaccination among pregnant African American women, a group of women who tend to have lower vaccine uptake compared with other groups. We conducted a prospective randomized controlled trial to pilot test two interventions - an affective messaging video and a cognitive messaging iBook - among pregnant African American women recruited during routine prenatal care visits. We measured Tdap vaccination during the perinatal period (during pregnancy and immediately postpartum), reasons for non-vaccination, and intention to receive Tdap in the next pregnancy. Among the enrolled women (n=106), 90% completed follow-up. Tdap vaccination in the perinatal period was 18% in the control group; 50% in the iBook group (Risk Ratio [vs. control group]: 2.83; 95% CI, 1.26-6.37), and 29% in the video group (RR: 1.65; 95% CI, 0.66-4.09). From baseline to follow-up, women's reported intention to receive Tdap during the next pregnancy improved in all three groups. Among unvaccinated women, the most common reason reported for non-vaccination was lack of a recommendation for Tdap by the woman's physician. Education interventions that provide targeted information for pregnant women in an interactive manner may be useful to improve Tdap vaccination during the perinatal period. However, larger studies including multiple racial and ethnic groups are needed to evaluate robustness of our findings. clinicaltrials.gov Identifier: NCT01740310. Copyright © 2017 Elsevier Ltd. All rights reserved.

Adapting Hypertension Self-Management Interventions to Enhance their Sustained Effectiveness among Urban African Americans

Science.gov (United States)

Ameling, Jessica M.; Ephraim, Patti L.; Bone, Lee R.; Levine, David M.; Roter, Debra L.; Wolff, Jennifer L.; Hill-Briggs, Felicia; Fitzpatrick, Stephanie L.; Noronha, Gary J.; Fagan, Peter J.; Lewis-Boyer, LaPricia; Hickman, Debra; Simmons, Michelle; Purnell, Leon; Fisher, Annette; Cooper, Lisa A.; Aboumatar, Hanan J.; Albert, Michael C.; Flynn, Sarah J.; Boulware, L. Ebony

2014-01-01

African Americans suffer disproportionately poor hypertension control despite the availability of efficacious interventions. Using principles of community-based participatory research and implementation science, we adapted established hypertension self-management interventions to enhance interventions’ cultural relevance and potential for sustained effectiveness among urban African Americans. We obtained input from patients and their family members, their health care providers, and community members. The process required substantial time and resources, and the adapted interventions will be tested in a randomized controlled trial. PMID:24569158

5-HTTLPR Polymorphism: Analysis in South African Autistic Individuals

KAUST Repository

Arieff, Zainunisha

2010-06-01

The serotonin transporter promoter length polymorphism (5-hydroxytryptamine transporter length polymorphism; 5-HTTLPR) has long been implicated in autism and other psychiatric disorders. The use of selective serotonin reuptake inhibitors (SSRIs) has a positive effect on treating some symptoms of autism. The effects of these drugs vary in individuals because of the presence of the S or L allele of 5-HTTLPR. Studies performed on various autistic populations have found different allele frequencies for the L and S alleles. Allele frequencies and genotypes of the South African autistic populations (African, mixed, and Caucasian) were compared with matching South African ethnic control populations. The *S/*S genotype was found to be highly significantly associated with all the South African autistic ethnic populations. In the South African African population the *S/*S genotype was present in 7 (33%) of the autistic individuals but in none of the control subjects, yielding infinitely large odds of developing autism. The odds of developing autism with the *S/*S genotype compared to the *L/*L genotype increased 10.15-fold in the South African mixed group and 2.74-fold in the South African Caucasian population. The allele frequency of the South African autistic population was also compared with studies of other autistic populations around the world, and highly significant differences were found with the Japanese, Korean, and Indian population groups. The difference was not significant for the French, German, Israeli, Portuguese, and American groups. This is the first South African study of autistic individuals of different ethnic backgrounds that shows significant differences in allele and genotype frequencies of 5-HTTLPR. The results of this study open new avenues for investigating the role of transmission of the L and S alleles in families with autism in South Africa.

5-HTTLPR Polymorphism: Analysis in South African Autistic Individuals

KAUST Repository

Arieff, Zainunisha; Kaur, Mandeep; Gameeldien, Hajirah; van der Merwe, Lize; Bajic, Vladimir B.

2010-01-01

The serotonin transporter promoter length polymorphism (5-hydroxytryptamine transporter length polymorphism; 5-HTTLPR) has long been implicated in autism and other psychiatric disorders. The use of selective serotonin reuptake inhibitors (SSRIs) has a positive effect on treating some symptoms of autism. The effects of these drugs vary in individuals because of the presence of the S or L allele of 5-HTTLPR. Studies performed on various autistic populations have found different allele frequencies for the L and S alleles. Allele frequencies and genotypes of the South African autistic populations (African, mixed, and Caucasian) were compared with matching South African ethnic control populations. The *S/*S genotype was found to be highly significantly associated with all the South African autistic ethnic populations. In the South African African population the *S/*S genotype was present in 7 (33%) of the autistic individuals but in none of the control subjects, yielding infinitely large odds of developing autism. The odds of developing autism with the *S/*S genotype compared to the *L/*L genotype increased 10.15-fold in the South African mixed group and 2.74-fold in the South African Caucasian population. The allele frequency of the South African autistic population was also compared with studies of other autistic populations around the world, and highly significant differences were found with the Japanese, Korean, and Indian population groups. The difference was not significant for the French, German, Israeli, Portuguese, and American groups. This is the first South African study of autistic individuals of different ethnic backgrounds that shows significant differences in allele and genotype frequencies of 5-HTTLPR. The results of this study open new avenues for investigating the role of transmission of the L and S alleles in families with autism in South Africa.

5-HTTLPR polymorphism: analysis in South African autistic individuals.

Science.gov (United States)

Arieff, Zainunisha; Kaur, Mandeep; Gameeldien, Hajirah; van der Merwe, Lize; Bajic, Vladimir B

2010-06-01

The serotonin transporter promoter length polymorphism (5-hydroxytryptamine transporter length polymorphism; 5-HTTLPR) has long been implicated in autism and other psychiatric disorders. The use of selective serotonin reuptake inhibitors (SSRIs) has a positive effect on treating some symptoms of autism. The effects of these drugs vary in individuals because of the presence of the S or L allele of 5-HTTLPR. Studies performed on various autistic populations have found different allele frequencies for the L and S alleles. Allele frequencies and genotypes of the South African autistic populations (African, mixed, and Caucasian) were compared with matching South African ethnic control populations. The *S/*S genotype was found to be highly significantly associated with all the South African autistic ethnic populations. In the South African African population the *S/*S genotype was present in 7 (33%) of the autistic individuals but in none of the control subjects, yielding infinitely large odds of developing autism. The odds of developing autism with the *S/*S genotype compared to the *L/*L genotype increased 10.15-fold in the South African mixed group and 2.74-fold in the South African Caucasian population. The allele frequency of the South African autistic population was also compared with studies of other autistic populations around the world, and highly significant differences were found with the Japanese, Korean, and Indian population groups. The difference was not significant for the French, German, Israeli, Portuguese, and American groups. This is the first South African study of autistic individuals of different ethnic backgrounds that shows significant differences in allele and genotype frequencies of 5-HTTLPR. The results of this study open new avenues for investigating the role of transmission of the L and S alleles in families with autism in South Africa.

Safety of a silicone elastomer vaginal ring as potential microbicide delivery method in African women: A Phase 1 randomized trial.

Science.gov (United States)

Nel, Annaléne; Martins, Janine; Bekker, Linda-Gail; Ramjee, Gita; Masenga, Gileard; Rees, Helen; van Niekerk, Neliëtte

2018-01-01

Women in sub-Saharan Africa are in urgent need of female-initiated human immunodeficiency virus (HIV) preventative methods. Vaginal rings are one dosage form in development for delivery of HIV microbicides. However, African women have limited experience with vaginal rings. This Phase I, randomized, crossover trial assessed and compared the safety, acceptability and adherence of a silicone elastomer placebo vaginal ring, intended as a microbicide delivery method, inserted for a 12-week period in healthy, HIV-negative, sexually active women in South Africa and Tanzania. 170 women, aged 18 to 35 years were enrolled with 88 women randomized to Group A, using a placebo vaginal ring for 12 weeks followed by a 12-week safety observation period. 82 women were randomized to Group B and observed for safety first, followed by a placebo vaginal ring for 12 weeks. Safety was assessed by clinical laboratory assessments, pelvic/colposcopy examinations and adverse events. Possible carry-over effect was addressed by ensuring no signs or symptoms of genital irritation at crossover. No safety concerns were identified for any safety variables assessed during the trial. No serious adverse events were reported considered related to the placebo vaginal ring. Vaginal candidiasis was the most common adverse event occurring in 11% of participants during each trial period. Vaginal discharge (2%), vaginal odour (2%), and bacterial vaginitis (2%) were assessed as possibly or probably related to the vaginal ring. Thirty-four percent of participants had sexually transmitted infections (STIs) at screening, compared to 12% of participants who tested positive for STIs at crossover and the final trial visit. Three participants (2%) tested HIV positive during the trial. The silicone elastomer vaginal ring had no safety concerns, demonstrating a profile favorable for further development for topical release of antiretroviral-based microbicides.

Perceptions of guided imagery for stress management in pregnant African American women.

Science.gov (United States)

Jallo, Nancy; Salyer, Jeanne; Ruiz, R Jeanne; French, Elise

2015-08-01

Maternal stress during pregnancy has been associated with numerous adverse pregnancy, birth, and health outcomes. Pregnant African American women have been reported to have higher levels of stress compared to other ethnic or racial groups underscoring the need for effective interventions to reduce stress in this population. The purpose of this study was to gain an in-depth understanding of the perceptions of guided imagery (GI) as a technique for stress management in a cohort of pregnant African American women who participated in a GI intervention as part of a larger mixed methods randomized controlled trial. The 12week intervention was a professionally recorded compact disc with four tracks developed and sequenced to reduce stress and associated symptoms. The findings from this descriptive phenomenologic study were derived from daily logs and interviews from 36 participants randomized to the GI group. Participants described the stressful nature of their lives. Results demonstrated pregnant African American women perceived the intervention as beneficial in reducing stress and the associated symptoms. The emergent themes suggested the intervention offered a respite from their stressful lives, reduced the negative emotional responses to stress and enhanced well-being, benefited other areas of their daily life, and provided an opportunity to connect with their baby. The study results support the perceived efficacy of GI as a stress coping intervention. GI is an economic as well as easy to implement, access and use technique that has potential stress coping benefits as perceived by pregnant African American women. Copyright © 2015 Elsevier Inc. All rights reserved.

Characteristics of men with substance use disorder consequent to illicit drug use: comparison of a random sample and volunteers.

Science.gov (United States)

Reynolds, Maureen D; Tarter, Ralph E; Kirisci, Levent

2004-09-06

Men qualifying for substance use disorder (SUD) consequent to consumption of an illicit drug were compared according to recruitment method. It was hypothesized that volunteers would be more self-disclosing and exhibit more severe disturbances compared to randomly recruited subjects. Personal, demographic, family, social, substance use, psychiatric, and SUD characteristics of volunteers (N = 146) were compared to randomly recruited (N = 102) subjects. Volunteers had lower socioceconomic status, were more likely to be African American, and had lower IQ than randomly recruited subjects. Volunteers also evidenced greater social and family maladjustment and more frequently had received treatment for substance abuse. In addition, lower social desirability response bias was observed in the volunteers. SUD was not more severe in the volunteers; however, they reported a higher lifetime rate of opiate, diet, depressant, and analgesic drug use. Volunteers and randomly recruited subjects qualifying for SUD consequent to illicit drug use are similar in SUD severity but differ in terms of severity of psychosocial disturbance and history of drug involvement. The factors discriminating volunteers and randomly recruited subjects are well known to impact on outcome, hence they need to be considered in research design, especially when selecting a sampling strategy in treatment research.

Emergency percutaneous tracheostomy | Jonas | South African ...

African Journals Online (AJOL)

South African Journal of Surgery. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 45, No 3 (2007) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Rhythm experience and Africana culture trial (REACT!): A culturally salient intervention to promote neurocognitive health, mood, and well-being in older African Americans.

Science.gov (United States)

Lukach, Alexis J; Jedrziewski, M Kathryn; Grove, George A; Mechanic-Hamilton, Dawn J; Williams, Shardae S; Wollam, Mariegold E; Erickson, Kirk I

2016-05-01

The Rhythm Experience and Africana Culture Trial (REACT!) is a multi-site randomized controlled intervention study designed to examine the efficacy of using African Dance as a form of moderate-intensity physical activity to improve cognitive function in older African Americans. African Americans are almost two times more likely than Caucasians to experience cognitive impairment in late adulthood. This increased risk may be attributed to lower level and quality of education, lower socioeconomic status, and higher prevalence of vascular diseases, type 2 diabetes, hypertension, and obesity, all of which are recognized as risk factors for dementia. Fortunately, interventions targeting cardiovascular health (i.e., physical activity) are associated with improved neurocognitive function and a reduced risk for dementia, so African Americans may be particularly suited for interventions targeting cardiovascular health and cognitive function. Here, we describe a randomized intervention protocol for increasing physical activity in older (65-75years) African Americans. Participants (n=80) at two study locations will be randomized into one of two groups. The treatment group will participate in African Dance three times per week for six months and the control group will receive educational training on Africana history and culture, as well as information about health behaviors, three times per week for six months. If successful, the REACT! study may transform community interventions and serve as a platform and model for testing other populations, age groups, and health outcomes, potentially identifying novel and creative methods for reducing or eliminating health disparities. Copyright © 2016 Elsevier Inc. All rights reserved.

Morphological Characterization of the African Giant Rat (Cricetomys ...

African Journals Online (AJOL)

olayemitoyin

gambianus, Waterhouse) Brain Across Age Groups: Gross Features of. Cortices ... Keywords: African giant rats, Brain, Morphology, Cerebrum, Cerebellum, Olfactory bulb ..... as shrinkage with aging rather than selective .... lasting increase in the number of proliferating cells, ... radial glia in the adult rat dentate gyrus.

Stealing Thunder: African Security Sector Reform, the Military’s New Challenge

Science.gov (United States)

2007-04-19

will become scarcer.3 If left unchecked Africa will remain an unending stew of ethnic warfare stimulating massive destabilizing and uncontrolled...this phenomenon, see: David Lamb , The Africans (New York, Random House, 1982) 149. 14 Meredith, 150 – 161. 15 For typical examples of Cold War

Macro-habitat preferences by the African manatee and crocodiles – ecological and conservation implications

Directory of Open Access Journals (Sweden)

L. Luiselli

2012-07-01

Full Text Available African manatees (Trichechus senegalensis and crocodiles are threatened species in parts of their range. In West Africa, crocodiles may constitute the main predators for manatees apart from humans. Here, we explore the macro-habitat selection of manatees and two species of crocodiles (West African crocodiles Crocodylus suchus and dwarf crocodile Osteolaemus tetraspis in the Niger Delta (Nigeria, testing the hypotheses that (i manatees may avoid crocodiles in order to minimize risks of predation, and (ii the two crocodile species do compete. The study was carried out between 1994 and 2010 with a suite of different field techniques. We observed that the main macro-habitat types were freshwater rivers and coastal lagoons for manatees, mangroves for West African crocodiles, and rivers and creeks for dwarf crocodiles, with (i the three species differing significantly in terms of their macro-habitat type selection, and (ii significant seasonal influence on habitat selection of each species. Null models for niche overlap showed a significantly lower overlap in macro-habitat type use between manatee and crocodiles, whereas the two crocodiles were relatively similar. Null model analyses did not indicate any competitive interactions between crocodiles. On the other hand, manatees avoided macro-habitats where crocodiles, and especially West African crocodiles, are abundant.

Towards an indigenous African bioethics | Behrens | South African ...

African Journals Online (AJOL)

One way is for African bioethicists to begin to apply indigenous African philosophy, thought and values to ethical issues. This project is important (i) to restore dignity; (ii) because a bioethics grounded in indigenous ideas is more likely to be accepted by Africans; and (iii) because such ideas can enrich bioethical discourse.

Female genital mutilation in African and African American women's literature

Directory of Open Access Journals (Sweden)

Darja Marinšek

2007-12-01

Full Text Available The article builds on the existing dispute between African and African American women writers on the competence of writing about female genital mutilation (FGM, and tries to determine the existence and nature of the differences between the writings of these two groups. The author uses comparative analysis of two popular African and African American novels, comparing their ways of describing FGM, its causes and consequences, the level ob objectivity and the style of the narrations.This is followed by a discussion on the reasons for such differences, incorporating a larger circle of both African and African American women authors, at the same time analysing the deviance within the two groups. While the differences between African American writers are not that great, as they mostly fail to present the issue from different points of view, which is often the result of their lack of direct knowledge of the topic, African authors' writing is in itself discovered to be ambivalent and not at all invariable. The reasons for such ambivalence are then discussed in greater context, focusing on the effect of the authors' personal contact with circumcision as well as their knowledge and acceptance of Western values. The author concludes by establishing the African ambivalent attitude towards FGM, which includes different aspects of the issue, as the most significant difference between their and African American writers' description of this practice.

Genetic evidence of African slavery at the beginning of the trans-Atlantic slave trade.

Science.gov (United States)

Martiniano, Rui; Coelho, Catarina; Ferreira, Maria Teresa; Neves, Maria João; Pinhasi, Ron; Bradley, Daniel G

2014-08-08

An archaeological excavation in Valle da Gafaria (Lagos, Portugal), revealed two contiguous burial places outside the medieval city walls, dating from the 15(th)-17(th) centuries AD: one was interpreted as a Leprosarium cemetery and the second as an urban discard deposit, where signs of violent, unceremonious burials suggested that these remains may belong to slaves captured in Africa by the Portuguese. We obtained random short autosomal sequence reads from seven individuals: two from the latter site and five from the Leprosarium and used these to call SNP identities and estimate ancestral affinities with modern reference data. The Leprosarium site samples were less preserved but gave some probability of both African and European ancestry. The two discard deposit burials each gave African affinity signals, which were further refined toward modern West African or Bantu genotyped samples. These data from distressed burials illustrate an African contribution to a low status stratum of Lagos society at a time when this port became a hub of the European trade in African slaves which formed a precursor to the transatlantic transfer of millions.

Tropical Atlantic Hurricanes, Easterly Waves, and West African Mesoscale Convective Systems

Directory of Open Access Journals (Sweden)

Yves K. Kouadio

2010-01-01

Full Text Available The relationship between tropical Atlantic hurricanes (Hs, atmospheric easterly waves (AEWs, and West African mesoscale convective systems (MCSs is investigated. It points out atmospheric conditions over West Africa before hurricane formation. The analysis was performed for two periods, June–November in 2004 and 2005, during which 12 hurricanes (seven in 2004, five in 2005 were selected. Using the AEW signature in the 700 hPa vorticity, a backward trajectory was performed to the African coast, starting from the date and position of each hurricane, when and where it was catalogued as a tropical depression. At this step, using the Meteosat-7 satellite dataset, we selected all the MCSs around this time and region, and tracked them from their initiation until their dissipation. This procedure allowed us to relate each of the selected Hs with AEWs and a succession of MCSs that occurred a few times over West Africa before initiation of the hurricane. Finally, a dipole in sea surface temperature (SST was observed with a positive SST anomaly within the region of H generation and a negative SST anomaly within the Gulf of Guinea. This SST anomaly dipole could contribute to enhance the continental convergence associated with the monsoon that impacts on the West African MCSs formation.

Determination of Some Heavy Metals in Selected Beauty and ...

African Journals Online (AJOL)

Several epidemiologic studies have investigated the potential carcinogenicity of human exposure to heavy metals from diverse sources but few or none was on African black and beauty soaps. Hence, this study examines the presence of some heavy metals in selected African black and beauty soaps commonly used in ...

Selection of procurement systems in the South African construction industry: An exploratory study

Directory of Open Access Journals (Sweden)

W. D. Thwala

2012-12-01

Full Text Available Purpose of this paper: Procurement systems are vital in ensuring the successful implementation of construction projects precisely in all the phases of any particular project. Therefore, this paper aims to investigate in a systematic manner the factors that influence the selection of a procurement system in the South African construction industry. Research methodology: An extensive theory and literature review of procurement systems was conducted. The literature reviewed included a sample of case studies of procurement systems successfully implemented in completed building and civil engineering projects in South Africa. A questionnaire using a four-round Delphi survey method was used to conduct the empirical study in order to obtain participants' opinions about factors influencing the selection of procurement systems as well as the utility value of various procurement systems on each factor as identified. Finally, data analysis of both qualitative and quantitative techniques was performed using the Statistical Package for Social Sciences (SPSS. Findings: After qualitative analysis, findings of the literature reviewed suggest that factors that influence the selection of procurement systems cut across all the phases of the project as identified in this paper. Therefore, these factors are categorically classified into internal and external factors. Factors from the internal environment were further classified into client characteristics and project characteristics, with client characteristics comprising of variables such as clients' level of knowledge and control, political and social consideration, familiarity of procurement systems, competition, funding arrangement, government public/private sector projects and risk allocation whereas project characteristics comprise of factors (variables such as size and technical complexity of the project, influence of the project life cycle, expedited project delivery, time, quality and price certainty. Factors

Using Random Forests to Select Optimal Input Variables for Short-Term Wind Speed Forecasting Models

Directory of Open Access Journals (Sweden)

Hui Wang

2017-10-01

Full Text Available Achieving relatively high-accuracy short-term wind speed forecasting estimates is a precondition for the construction and grid-connected operation of wind power forecasting systems for wind farms. Currently, most research is focused on the structure of forecasting models and does not consider the selection of input variables, which can have significant impacts on forecasting performance. This paper presents an input variable selection method for wind speed forecasting models. The candidate input variables for various leading periods are selected and random forests (RF is employed to evaluate the importance of all variable as features. The feature subset with the best evaluation performance is selected as the optimal feature set. Then, kernel-based extreme learning machine is constructed to evaluate the performance of input variables selection based on RF. The results of the case study show that by removing the uncorrelated and redundant features, RF effectively extracts the most strongly correlated set of features from the candidate input variables. By finding the optimal feature combination to represent the original information, RF simplifies the structure of the wind speed forecasting model, shortens the training time required, and substantially improves the model’s accuracy and generalization ability, demonstrating that the input variables selected by RF are effective.

Genetic ancestry-smoking interactions and lung function in African Americans: a cohort study.

Directory of Open Access Journals (Sweden)

Melinda C Aldrich

Full Text Available BACKGROUND: Smoking tobacco reduces lung function. African Americans have both lower lung function and decreased metabolism of tobacco smoke compared to European Americans. African ancestry is also associated with lower pulmonary function in African Americans. We aimed to determine whether African ancestry modifies the association between smoking and lung function and its rate of decline in African Americans. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated a prospective ongoing cohort of 1,281 African Americans participating in the Health, Aging, and Body Composition (Health ABC Study initiated in 1997. We also examined an ongoing prospective cohort initiated in 1985 of 1,223 African Americans in the Coronary Artery Disease in Young Adults (CARDIA Study. Pulmonary function and tobacco smoking exposure were measured at baseline and repeatedly over the follow-up period. Individual genetic ancestry proportions were estimated using ancestry informative markers selected to distinguish European and West African ancestry. African Americans with a high proportion of African ancestry had lower baseline forced expiratory volume in one second (FEV₁ per pack-year of smoking (-5.7 ml FEV₁/ smoking pack-year compared with smokers with lower African ancestry (-4.6 ml in FEV₁/ smoking pack-year (interaction P value  = 0.17. Longitudinal analyses revealed a suggestive interaction between smoking, and African ancestry on the rate of FEV(1 decline in Health ABC and independently replicated in CARDIA. CONCLUSIONS/SIGNIFICANCE: African American individuals with a high proportion of African ancestry are at greater risk for losing lung function while smoking.

Risk and protection for HIV/AIDS in African-American, Hispanic, and White adolescents.

Science.gov (United States)

Bartlett, Robin; Buck, Raymond; Shattell, Mona M

2008-07-01

African-Americans and Hispanics are disproportionately affected by HIV/AIDS in the United States. HIV infection is often acquired during adolescence, a time when risky sexual behaviors are at their peak. This study explored relationships among selected risk factors, protective factors, and risky sexual behaviors among African-American, Hispanic, and White adolescents, from a sample of adolescents from the National Longitudinal Study of Adolescent Health. African-Americans and Hispanics were more likely to have sexual intercourse without the use of birth control than were Whites. African-Americans were more likely to have sexual behavior with multiple sexual partners than either Hispanics or Whites were, and African-Americans had higher self-esteem than did Hispanics and Whites. In order to develop culturally sensitive, effective interventions to prevent HIV/AIDS in adolescents, racial differences in risk and protective factors must be examined.

Molossid bats in an African agro-ecosystem select sugarcane fields as foraging habitat

DEFF Research Database (Denmark)

Noer, Christina Lehmkuhl; Dabelsteen, Torben; Bohmann, Kristine

2012-01-01

Two coexisting species of African molossids, the little free-tailed bat, Chaerephon pumilus, and the Angolan free-tailed bat, Mops condylurus, were studied in the lowveld of Swaziland. Nine C. pumilus and five M. condylurus, all non-lactating females, were radio-tracked in order to investigate...

The Genetic Structure and History of Africans and African Americans

Science.gov (United States)

Tishkoff, Sarah A.; Reed, Floyd A.; Friedlaender, Françoise R.; Ehret, Christopher; Ranciaro, Alessia; Froment, Alain; Hirbo, Jibril B.; Awomoyi, Agnes A.; Bodo, Jean-Marie; Doumbo, Ogobara; Ibrahim, Muntaser; Juma, Abdalla T.; Kotze, Maritha J.; Lema, Godfrey; Moore, Jason H.; Mortensen, Holly; Nyambo, Thomas B.; Omar, Sabah A.; Powell, Kweli; Pretorius, Gideon S.; Smith, Michael W.; Thera, Mahamadou A.; Wambebe, Charles; Weber, James L.; Williams, Scott M.

2010-01-01

Africa is the source of all modern humans, but characterization of genetic variation and of relationships among populations across the continent has been enigmatic. We studied 121 African populations, four African American populations, and 60 non-African populations for patterns of variation at 1327 nuclear microsatellite and insertion/deletion markers. We identified 14 ancestral population clusters in Africa that correlate with self-described ethnicity and shared cultural and/or linguistic properties. We observed high levels of mixed ancestry in most populations, reflecting historical migration events across the continent. Our data also provide evidence for shared ancestry among geographically diverse hunter-gatherer populations (Khoesan speakers and Pygmies). The ancestry of African Americans is predominantly from Niger-Kordofanian (~71%), European (~13%), and other African (~8%) populations, although admixture levels varied considerably among individuals. This study helps tease apart the complex evolutionary history of Africans and African Americans, aiding both anthropological and genetic epidemiologic studies. PMID:19407144

Random blood glucose may be used to assess long-term glycaemic control among patients with type 2 diabetes mellitus in a rural African clinical setting

DEFF Research Database (Denmark)

Rasmussen, Jon B; Nordin, Lovisa S; Rasmussen, Niclas S

2014-01-01

clinical review only. Other information obtained was age, sex, body mass index, waist circumference, blood pressure, urine albumin-creatinine ratio, duration since diagnosis and medication. RESULTS: One hundred and one patients with DM (type 1 DM = 23, type 2 DM = 78) were included. Spearman's rank......OBJECTIVES: To investigate the diagnostic accuracy of random blood glucose (RBG) on good glycaemic control among patients with diabetes mellitus (DM) in a rural African setting. METHODS: Cross-sectional study at St. Francis' Hospital in eastern Zambia. RBG and HbA1c were measured during one.......24-0.32, P AUC = 0.80, SE = 0.05), RBG ≤7.5 mmol/l was determined as the optimal cut-off value for good glycaemic control (HbA1c

Neighborhood Conditions and Psychosocial Outcomes Among Middle-Aged African Americans.

Science.gov (United States)

Tabet, Maya; Sanders, Erin A; Schootman, Mario; Chang, Jen Jen; Wolinsky, Fredric D; Malmstrom, Theodore K; Miller, Douglas K

2017-04-01

We examined associations between observed neighborhood conditions (good/adverse) and psychosocial outcomes (stress, depressive symptoms, resilience, and sense of control) among middle-aged and older African Americans. The sample included 455 middle-aged and older African Americans examined in Wave 10 of the African American Health (AAH) study. Linear regression was adjusted for attrition, self-selection into neighborhoods, and potential confounders, and stratified by the duration at current address (stress (standardized β = -0.18; P = .002) and depressive symptoms (standardized β = -0.12; P = .048). Among those who lived at their current address for stress (standardized β = 0.18; P = .305) or depressive symptoms (standardized β = 0.36; P = .080). Neighborhood conditions appear to have significant, complex associations with psychosocial factors among middle-aged and older African Americans. This holds important policy implications, especially since adverse neighborhood conditions may still result in adverse physical health outcomes in individuals with >5 years at current residence despite being associated with better psychosocial outcomes.

Treatment Options for Insomnia | Ramakrishnan | South African ...

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 49, No 8 (2007) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Depression in Kraepelinian schizophrenia | Naude | South African ...

African Journals Online (AJOL)

South African Journal of Psychiatry. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 15, No 4 (2009) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Resilience among first responders | Pietrantoni | African Health ...

African Journals Online (AJOL)

African Health Sciences. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 8 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if ...

Central nervous system tuberculosis | Cherian | African Health ...

African Journals Online (AJOL)

African Health Sciences. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 11, No 1 (2011) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

Efficacy and immunogenicity of two or three dose rotavirus-vaccine regimen in South African children over two consecutive rotavirus-seasons: a randomized, double-blind, placebo-controlled trial.

Science.gov (United States)

Madhi, S A; Kirsten, M; Louw, C; Bos, P; Aspinall, S; Bouckenooghe, A; Neuzil, K M; Steele, A D

2012-04-27

Human rotavirus vaccine (HRV; i.e., Rotarix) reduced the incidence of severe rotavirus gastroenteritis (RVGE) by 77% (95% Confidence interval: 56-88%) during the first year of life in South Africa. Persistence of HRV-derived protection against RVGE during subsequent rotavirus seasons, although evident in industrialized settings, remains to be established in African settings. This study reports on the efficacy of HRV against severe RVGE over two consecutive rotavirus seasons in South African children. A prospective, double-blind, placebo controlled multi-centered trial in South Africa and Malawi randomly assigned infants in a 1:1:1 ratio to receive either two (10 and 14 weeks; HRV_2D) or three (6, 10 and 14 weeks; HRV_3D) doses of HRV or placebo. The primary analysis involved pooling of HRV_2D and HRV_3D arms. Episodes of gastroenteritis caused by wild-type rotavirus were identified through active follow-up surveillance and graded by the Vesikari scale. 1339 infants (447 in the HRV_2D group, 447 in the HRV_3D group and 445 in the placebo group) were enrolled in Year 2 of the study, including 1035 (77.3%) who were followed up over two consecutive rotavirus seasons (i.e., Cohort 2 subjects). Rotarix was associated with ongoing protection against severe RVGE, preventing 2.5 episodes per 100 vaccinated children over two consecutive rotavirus seasons; vaccine efficacy: 59% (95% Confidence interval: 1-83%). An exploratory analysis indicated better immunogenicity (among Cohort 1 subjects) and a higher point-efficacy estimate over two seasons in the HRV_3D compared to HRV_2D arms of the study in Cohort 2 subjects. Rotarix is associated with significant reductions in severe gastroenteritis episodes through 2 years of life among South African children. Further research is needed to determine the optimal dosing schedule of Rotarix in providing long-term protection against rotavirus illness in African children. Copyright © 2011 Elsevier Ltd. All rights reserved.

Loci associated with skin pigmentation identified in African populations

Science.gov (United States)

Crawford, Nicholas G.; Kelly, Derek E.; Hansen, Matthew E. B.; Beltrame, Marcia H.; Fan, Shaohua; Bowman, Shanna L.; Jewett, Ethan; Ranciaro, Alessia; Thompson, Simon; Lo, Yancy; Pfeifer, Susanne P.; Jensen, Jeffrey D.; Campbell, Michael C.; Beggs, William; Hormozdiari, Farhad; Mpoloka, Sununguko Wata; Mokone, Gaonyadiwe George; Nyambo, Thomas; Meskel, Dawit Wolde; Belay, Gurja; Haut, Jake; Rothschild, Harriet; Zon, Leonard; Zhou, Yi; Kovacs, Michael A.; Xu, Mai; Zhang, Tongwu; Bishop, Kevin; Sinclair, Jason; Rivas, Cecilia; Elliot, Eugene; Choi, Jiyeon; Li, Shengchao A.; Hicks, Belynda; Burgess, Shawn; Abnet, Christian; Watkins-Chow, Dawn E.; Oceana, Elena; Song, Yun S.; Eskin, Eleazar; Brown, Kevin M.; Marks, Michael S.; Loftus, Stacie K.; Pavan, William J.; Yeager, Meredith; Chanock, Stephen; Tishkoff, Sarah

2017-01-01

Despite the wide range of skin pigmentation in humans, little is known about its genetic basis in global populations. Examining ethnically diverse African genomes, we identify variants in or near SLC24A5, MFSD12, DDB1, TMEM138, OCA2 and HERC2 that are significantly associated with skin pigmentation. Genetic evidence indicates that the light pigmentation variant at SLC24A5 was introduced into East Africa by gene flow from non-Africans. At all other loci, variants associated with dark pigmentation in Africans are identical by descent in southern Asian and Australo-Melanesian populations. Functional analyses indicate that MFSD12 encodes a lysosomal protein that affects melanogenesis in zebrafish and mice, and that mutations in melanocyte-specific regulatory regions near DDB1/TMEM138 correlate with expression of UV response genes under selection in Eurasians. PMID:29025994

Investigating the treatment of missing data in an Olympiad-type test – the case of the selection validity in the South African Mathematics Olympiad

Directory of Open Access Journals (Sweden)

Caroline Long

2016-10-01

Full Text Available The purpose of the South African Mathematics Olympiad is to generate interest in mathematics and to identify the most talented mathematical minds. Our focus is on how the handling of missing data affects the selection of the ‘best’ contestants. Two approaches handling missing data, applying the Rasch model, are described. The issue of guessing is investigated through a tailored analysis. We present two microanalyses to illustate how missing data may impact selection; the first investigates groups of contestants that may miss selection under particular conditions; the second focuses on two contestants each of whom answer 14 items correctly. This comparison raises questions about the proportion of correct to incorrect answers. Recommendations are made for future scoring of the test, which include reconsideration of negative marking and weighting as well as considering the inclusion of 150 or 200 contestants as opposed to 100 contestants for participation in the final round.

Authenticity of a South African Dining Experience: Tourists ...

African Journals Online (AJOL)

A mixed methods research design was followed and a systematic sampling method was used to select respondents. ... in their menus and, for commercial purposes a staged South African experience be created using such strategies as manipulating the music, interior décor and anything that identifies with South Africa.

“Sunshine, sweat, and tears”: African-American ties to land and forests in the south

Science.gov (United States)

John Schelhas; Sarah Hitchner; Cassandra Johnson Gaither; Viniece. Jennings

2017-01-01

The Sustainable Forestry and African American Land Retention Program is a comprehensive effort to address the longstanding problem of under-participation of African Americans in forest management. This report describes the results of rapid appraisal baseline research for pilot projects in this program in three Southern States. The research used a carefully selected...

Management of treatment resistant schizophrenia | Jones | African ...

African Journals Online (AJOL)

African Journal of Psychiatry. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 9, No 1 (2006) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

Neonatal Vitamin A supplementation | Humphrey | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 89, No 2 (1999) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Histiocytosis X | Mohammed | Annals of African Medicine

African Journals Online (AJOL)

Annals of African Medicine. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 8, No 1 (2009) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your Web ...

Reproductive hormones as psychotropic agents? | Berk | African ...

African Journals Online (AJOL)

African Journal of Psychiatry. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 5, No 2 (2002) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

Globalisation, transport and HIV | Andrews | Southern African ...

African Journals Online (AJOL)

Southern African Journal of HIV Medicine. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 5, No 4 (2004) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Bronchiectasis: a bacteriological profile | Bopaka | Pan African ...

African Journals Online (AJOL)

Pan African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 22, No 1 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Management accounting for hospitals | Leyenaar | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 87, No 10 (1997) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Selected Developments in South African Labour Legislation related to Persons with Disabilities

Directory of Open Access Journals (Sweden)

Yvette Basson

2017-04-01

Full Text Available In South Africa marginalised groups have historically been afforded legislative protection in order to ensure that the rights of these groups are respected, protected, promoted and fulfilled. Examples of two such groups are older persons, whose rights are provided for in terms of the Older Persons Act 13 of 2006 and children, whose rights are provided for in terms of the Children's Act 38 of 2005. Persons with disabilities have, however, not yet been the subject of dedicated legislation outlining the content of the rights to which they are entitled. As a result of this lack of dedicated legislation, the rights of persons with disabilities are dealt with in a piecemeal fashion, often in disparate pieces of legislation. In addition to this focus on the rights of persons with disabilities, South African labour law has recently undergone extensive amendments. These amendments have led to the rights of persons with disabilities in the workplace being affected substantially. Since these amendments are as yet untested, little scrutiny of these provisions and the effect they may have on persons with disabilities has been undertaken. This article will thus discuss selected amendments of the labour legislation, and interrogate the practical effect these amendments may have on the rights of such persons. Of particular importance for the purposes of this article is the updating of an existing institution known as Sheltered Employment Factories, as well as the introduction of harsher penalties for employers who remain non-compliant with certain provisions of the Employment Equity Act 55 of 1998.

Micropropagation of African violet (Saintpaulia ionantha Wendl.).

Science.gov (United States)

Shukla, Mukund; Sullivan, J Alan; Jain, Shri Mohan; Murch, Susan J; Saxena, Praveen K

2013-01-01

Micropropagation is an important tool for rapid multiplication and the creation of genetic variability in African violets (Saintpaulia ionantha Wendl.). Successful in vitro propagation depends on the specific requirements and precise manipulation of various factors such as the type of explants used, physiological state of the mother plant, plant growth regulators in the culture medium, and growth conditions. Development of cost-effective protocols with a high rate of multiplication is a crucial requirement for commercial application of micropropagation. The current chapter describes an optimized protocol for micropropagation of African violets using leaf explants obtained from in vitro grown plants. In this process, plant regeneration occurs via both somatic embryogenesis and shoot organogenesis simultaneously in the explants induced with the growth regulator thidiazuron (TDZ; N-phenyl-N'-1,2,3-thidiazol-5-ylurea). The protocol is simple, rapid, and efficient for large-scale propagation of African violet and the dual routes of regeneration allow for multiple applications of the technology from simple clonal propagation to induction or selection of variants to the production of synthetic seeds.

African Americans' opinions about human-genetics research.

Science.gov (United States)

Achter, Paul; Parrott, Roxanne; Silk, Kami

2004-03-01

Research on attitudes toward genetics and medicine registers skepticism among minority communities, but the reasons for this skepticism are not well known. In the past, studies linked mistrust of the medical system to historical ethics violations involving minority groups and to suspicions about ideological premise and political intent. To assess public knowledge, attitudes, and behavior regarding human-genetics research, we surveyed 858 Americans onsite in four community settings or online in a geographically nonspecific manner. Compared to participants as a whole, African Americans were significantly more likely to believe that clinical trials might be dangerous and that the federal government knowingly conducted unethical research, including studies in which risky vaccines were administered to prison populations. However, African Americans were also significantly more likely to believe that the federal government worked to prevent environmental exposure to toxicants harmful to people with genetic vulnerabilities. Our data suggest that most Americans trust government to act ethically in sponsoring and conducting research, including genetics research, but that African Americans are particularly likely to see government as powerfully protective in some settings yet selectively disingenuous in others.

NORMS IN BRITISH AND SOUTH AFRICAN ENGLISH E. Ridge http ...

African Journals Online (AJOL)

standard English as "that kind of English which draws least attention to itself". For this ..... to linguistic or communicative norms, putative sex-indefinite pronouns among them ... South African English has necessarily been rather selective. It does ...

Implications of structural genomics target selection strategies: Pfam5000, whole genome, and random approaches

Energy Technology Data Exchange (ETDEWEB)

Chandonia, John-Marc; Brenner, Steven E.

2004-07-14

The structural genomics project is an international effort to determine the three-dimensional shapes of all important biological macromolecules, with a primary focus on proteins. Target proteins should be selected according to a strategy which is medically and biologically relevant, of good value, and tractable. As an option to consider, we present the Pfam5000 strategy, which involves selecting the 5000 most important families from the Pfam database as sources for targets. We compare the Pfam5000 strategy to several other proposed strategies that would require similar numbers of targets. These include including complete solution of several small to moderately sized bacterial proteomes, partial coverage of the human proteome, and random selection of approximately 5000 targets from sequenced genomes. We measure the impact that successful implementation of these strategies would have upon structural interpretation of the proteins in Swiss-Prot, TrEMBL, and 131 complete proteomes (including 10 of eukaryotes) from the Proteome Analysis database at EBI. Solving the structures of proteins from the 5000 largest Pfam families would allow accurate fold assignment for approximately 68 percent of all prokaryotic proteins (covering 59 percent of residues) and 61 percent of eukaryotic proteins (40 percent of residues). More fine-grained coverage which would allow accurate modeling of these proteins would require an order of magnitude more targets. The Pfam5000 strategy may be modified in several ways, for example to focus on larger families, bacterial sequences, or eukaryotic sequences; as long as secondary consideration is given to large families within Pfam, coverage results vary only slightly. In contrast, focusing structural genomics on a single tractable genome would have only a limited impact in structural knowledge of other proteomes: a significant fraction (about 30-40 percent of the proteins, and 40-60 percent of the residues) of each proteome is classified in small

Genome-wide association data classification and SNPs selection using two-stage quality-based Random Forests.

Science.gov (United States)

Nguyen, Thanh-Tung; Huang, Joshua; Wu, Qingyao; Nguyen, Thuy; Li, Mark

2015-01-01

Single-nucleotide polymorphisms (SNPs) selection and identification are the most important tasks in Genome-wide association data analysis. The problem is difficult because genome-wide association data is very high dimensional and a large portion of SNPs in the data is irrelevant to the disease. Advanced machine learning methods have been successfully used in Genome-wide association studies (GWAS) for identification of genetic variants that have relatively big effects in some common, complex diseases. Among them, the most successful one is Random Forests (RF). Despite of performing well in terms of prediction accuracy in some data sets with moderate size, RF still suffers from working in GWAS for selecting informative SNPs and building accurate prediction models. In this paper, we propose to use a new two-stage quality-based sampling method in random forests, named ts-RF, for SNP subspace selection for GWAS. The method first applies p-value assessment to find a cut-off point that separates informative and irrelevant SNPs in two groups. The informative SNPs group is further divided into two sub-groups: highly informative and weak informative SNPs. When sampling the SNP subspace for building trees for the forest, only those SNPs from the two sub-groups are taken into account. The feature subspaces always contain highly informative SNPs when used to split a node at a tree. This approach enables one to generate more accurate trees with a lower prediction error, meanwhile possibly avoiding overfitting. It allows one to detect interactions of multiple SNPs with the diseases, and to reduce the dimensionality and the amount of Genome-wide association data needed for learning the RF model. Extensive experiments on two genome-wide SNP data sets (Parkinson case-control data comprised of 408,803 SNPs and Alzheimer case-control data comprised of 380,157 SNPs) and 10 gene data sets have demonstrated that the proposed model significantly reduced prediction errors and outperformed

Abundance, movements and habitat use by African Grey Parrots ...

African Journals Online (AJOL)

Populations of African Grey Parrots are threatened by increased forest loss and the pet trade. Budongo forest reserve has, for over 60 years, been subjected to selective logging. Mabira forest reserve faces human pressures characterised by extractive disturbances, and agricultural activities with increased boundary ...

Lessons in Success: A Multi-Campus Study of Factors Influencing Academic Accomplishment among High-Achieving African American Students at Private Liberal Arts Colleges

Science.gov (United States)

Johnson, Ryan A.

2013-01-01

The purpose of this study was to explore the academic experiences of highly successful African-American male graduates of small, private liberal arts colleges using a qualitative approach. Fourteen highly successful alumni from selective, private colleges were purposefully selected for the study, including seven African-American males and seven…

African Journals Online (AJOL)

African Journals Online (AJOL)

It has also been difficult for African researchers to access the work of other African academics. In partnership with hundreds of journals from all over the continent, AJOL works to change this, so that African-origin research output is available to Africans and to the rest of the world. AJOL is ... African Journal of AIDS Research.

Immunizations and African Americans

Science.gov (United States)

... Data > Minority Population Profiles > Black/African American > Immunizations Immunizations and African Americans African American adults are less ... 19 to 35 months had comparable rates of immunization. African American women are as likely to have ...

Smoking cessation among African American and white smokers in the Veterans Affairs health care system.

Science.gov (United States)

Burgess, Diana J; van Ryn, Michelle; Noorbaloochi, Siamak; Clothier, Barbara; Taylor, Brent C; Sherman, Scott; Joseph, Anne M; Fu, Steven S

2014-09-01

We examined whether a proactive care smoking cessation intervention designed to overcome barriers to treatment would be especially effective at increasing cessation among African Americans receiving care in the Veterans Health Administration. We analyzed data from a randomized controlled trial, the Veterans Victory over Tobacco study, involving a population-based electronic registry of current smokers (702 African Americans, 1569 whites) and assessed 6-month prolonged smoking abstinence at 1 year via a follow-up survey of all current smokers. We also examined candidate risk adjustors for the race effect on smoking abstinence. The interaction between patient race and intervention condition (proactive care vs. usual care) was not significant. Overall, African Americans had higher quit rates than Whites (13% vs. 9%; P Whites. These findings may be a result of the large number of veterans receiving smoking cessation services and the lack of racial differences in receipt of these services as well as racial differences in smoking history, self-efficacy, and motivation to quit that favor African Americans.

Genome sequence, population history, and pelage genetics of the endangered African wild dog (Lycaon pictus).

Science.gov (United States)

Campana, Michael G; Parker, Lillian D; Hawkins, Melissa T R; Young, Hillary S; Helgen, Kristofer M; Szykman Gunther, Micaela; Woodroffe, Rosie; Maldonado, Jesús E; Fleischer, Robert C

2016-12-09

The African wild dog (Lycaon pictus) is an endangered African canid threatened by severe habitat fragmentation, human-wildlife conflict, and infectious disease. A highly specialized carnivore, it is distinguished by its social structure, dental morphology, absence of dewclaws, and colorful pelage. We sequenced the genomes of two individuals from populations representing two distinct ecological histories (Laikipia County, Kenya and KwaZulu-Natal Province, South Africa). We reconstructed population demographic histories for the two individuals and scanned the genomes for evidence of selection. We show that the African wild dog has undergone at least two effective population size reductions in the last 1,000,000 years. We found evidence of Lycaon individual-specific regions of low diversity, suggestive of inbreeding or population-specific selection. Further research is needed to clarify whether these population reductions and low diversity regions are characteristic of the species as a whole. We documented positive selection on the Lycaon mitochondrial genome. Finally, we identified several candidate genes (ASIP, MITF, MLPH, PMEL) that may play a role in the characteristic Lycaon pelage.

Scientia Militaria: South African Journal of Military Studies

African Journals Online (AJOL)

Morale among French colonial troops on the Western Front during World War I: 1914–1918. ... Scientia Militaria: South African Journal of Military Studies ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader).

Attitudes and beliefs associated with leisure-time physical activity among African American adults.

Science.gov (United States)

Affuso, Olivia; Cox, Tiffany L; Durant, Nefertiti H; Allison, David B

2011-01-01

More than 60% of African American adults do not meet recommendations for moderate physical activity. We sought to discover the extent to which health attitudes and beliefs are associated with leisure-time physical activity in this population. Cross-sectional study. African American adults were asked about their health attitudes and beliefs during a national survey. Participants were 807 African American men and women aged 18 years and older. Random-digit dialing was employed, sampling telephone numbers by geographical region, area code, and population size. Participants were asked six health belief questions on the importance of exercise and body weight in health. Logistic regression was used to determine which of these factors were associated with physical activity participation. The percent of respondents participating in some form of physical activity during the past month was 87.1% in men and 82.9% in women. Factors associated with previous month physical activity in men were perceived personal importance of exercise (P importance of exercise (P important to exercise or be physically active for health predicts physical activity participation in both African American men and women. Creating a sense of importance of physical activity to relieve stress and foster good health may stimulate physical activity participation in African American adults.

Participant-selected music and physical activity in older adults following cardiac rehabilitation: a randomized controlled trial.

Science.gov (United States)

Clark, Imogen N; Baker, Felicity A; Peiris, Casey L; Shoebridge, Georgie; Taylor, Nicholas F

2017-03-01

To evaluate effects of participant-selected music on older adults' achievement of activity levels recommended in the physical activity guidelines following cardiac rehabilitation. A parallel group randomized controlled trial with measurements at Weeks 0, 6 and 26. A multisite outpatient rehabilitation programme of a publicly funded metropolitan health service. Adults aged 60 years and older who had completed a cardiac rehabilitation programme. Experimental participants selected music to support walking with guidance from a music therapist. Control participants received usual care only. The primary outcome was the proportion of participants achieving activity levels recommended in physical activity guidelines. Secondary outcomes compared amounts of physical activity, exercise capacity, cardiac risk factors, and exercise self-efficacy. A total of 56 participants, mean age 68.2 years (SD = 6.5), were randomized to the experimental ( n = 28) and control groups ( n = 28). There were no differences between groups in proportions of participants achieving activity recommended in physical activity guidelines at Week 6 or 26. Secondary outcomes demonstrated between-group differences in male waist circumference at both measurements (Week 6 difference -2.0 cm, 95% CI -4.0 to 0; Week 26 difference -2.8 cm, 95% CI -5.4 to -0.1), and observed effect sizes favoured the experimental group for amounts of physical activity (d = 0.30), exercise capacity (d = 0.48), and blood pressure (d = -0.32). Participant-selected music did not increase the proportion of participants achieving recommended amounts of physical activity, but may have contributed to exercise-related benefits.

African Journals: An Evaluation of their Use in African Universities ...

African Journals Online (AJOL)

The use of African published journals in two African universities was surveyed through the use of questionnaire, interviews, journal usage count and citation analysis. The survey reveals that African published journals are not popular with academics because of lack of bibliographic and physical access. For conclusion to be ...

r2VIM: A new variable selection method for random forests in genome-wide association studies.

Science.gov (United States)

Szymczak, Silke; Holzinger, Emily; Dasgupta, Abhijit; Malley, James D; Molloy, Anne M; Mills, James L; Brody, Lawrence C; Stambolian, Dwight; Bailey-Wilson, Joan E

2016-01-01

Machine learning methods and in particular random forests (RFs) are a promising alternative to standard single SNP analyses in genome-wide association studies (GWAS). RFs provide variable importance measures (VIMs) to rank SNPs according to their predictive power. However, in contrast to the established genome-wide significance threshold, no clear criteria exist to determine how many SNPs should be selected for downstream analyses. We propose a new variable selection approach, recurrent relative variable importance measure (r2VIM). Importance values are calculated relative to an observed minimal importance score for several runs of RF and only SNPs with large relative VIMs in all of the runs are selected as important. Evaluations on simulated GWAS data show that the new method controls the number of false-positives under the null hypothesis. Under a simple alternative hypothesis with several independent main effects it is only slightly less powerful than logistic regression. In an experimental GWAS data set, the same strong signal is identified while the approach selects none of the SNPs in an underpowered GWAS. The novel variable selection method r2VIM is a promising extension to standard RF for objectively selecting relevant SNPs in GWAS while controlling the number of false-positive results.

Is Communication a Mechanism of Relationship Education Effects among Rural African Americans?

Science.gov (United States)

Barton, Allen W; Beach, Steven R H; Lavner, Justin A; Bryant, Chalandra M; Kogan, Steven M; Brody, Gene H

2017-10-01

Enhancing communication as a means of promoting relationship quality has been increasingly questioned, particularly for couples at elevated sociodemographic risk. In response, the current study investigated communication change as a mechanism accounting for changes in relationship satisfaction and confidence among 344 rural, predominantly low-income African American couples with an early adolescent child who participated in a randomized controlled trial of the Protecting Strong African American Families (ProSAAF) program. Approximately 9 months after baseline assessment, intent-to-treat analyses indicated ProSAAF couples demonstrated improved communication, satisfaction, and confidence compared with couples in the control condition. Improvements in communication mediated ProSAAF effects on relationship satisfaction and confidence; conversely, neither satisfaction nor confidence mediated intervention effects on changes in communication. These results underscore the short-term efficacy of a communication-focused, culturally sensitive prevention program and suggest that communication is a possible mechanism of change in relationship quality among low-income African American couples.

African Journals Online (AJOL)

African Journals Online (AJOL)

African Journals OnLine (AJOL) is the world's largest online library of ... AJOL works to change this, so that African-origin research output is available to Africans ... South African Medical Journal ... Global Journal of Pure and Applied Sciences.

Dietary adequacies among South African adults in rural KwaZulu-Natal.

Science.gov (United States)

Kolahdooz, Fariba; Spearing, Kerry; Sharma, Sangita

2013-01-01

Food quality, determined by micronutrient content, is a stronger determinant of nutritional status than food quantity. Health concerns resulting from the co-existence of over-nutrition and under-nutrition in low income populations in South Africa have been fully recognized in the last two decades. This study aimed to further investigate dietary adequacy amongst adults in rural KwaZulu-Natal, by determining daily energy and nutrient intakes, and identifying the degree of satisfaction of dietary requirements. Cross-sectional study assessing dietary adequacy from 24-hour dietary recalls of randomly selected 136 adults in Empangeni, KwaZulu-Natal, South Africa. Results are presented for men (n = 52) and women (n = 84) 19-50 and >50 years old. Mean energy intake was greatest in women >50 years (2852 kcal/day) and exceeded Dietary Reference Intake's for both men and women, regardless of age. Mean daily energy intake from carbohydrates was 69% for men and 67% for women, above the Dietary Reference Intake range of 45-65%. Sodium was also consumed in excess, and the Dietary Reference Intakes of vitamins A, B12, C, D, and E, calcium, zinc and pantothenic acid were not met by the majority of the population. Despite mandatory fortification of staple South African foods, micronutrient inadequacies are evident among adults in rural South African communities. Given the excess caloric intake and the rising prevalence of obesity and other non-communicable diseases in South Africa, a focus on diet quality may be a more effective approach to influence micronutrient status than a focus on diet quantity.

Identifying tagging SNPs for African specific genetic variation from the African Diaspora Genome.

Science.gov (United States)

Johnston, Henry Richard; Hu, Yi-Juan; Gao, Jingjing; O'Connor, Timothy D; Abecasis, Gonçalo R; Wojcik, Genevieve L; Gignoux, Christopher R; Gourraud, Pierre-Antoine; Lizee, Antoine; Hansen, Mark; Genuario, Rob; Bullis, Dave; Lawley, Cindy; Kenny, Eimear E; Bustamante, Carlos; Beaty, Terri H; Mathias, Rasika A; Barnes, Kathleen C; Qin, Zhaohui S

2017-04-21

A primary goal of The Consortium on Asthma among African-ancestry Populations in the Americas (CAAPA) is to develop an 'African Diaspora Power Chip' (ADPC), a genotyping array consisting of tagging SNPs, useful in comprehensively identifying African specific genetic variation. This array is designed based on the novel variation identified in 642 CAAPA samples of African ancestry with high coverage whole genome sequence data (~30× depth). This novel variation extends the pattern of variation catalogued in the 1000 Genomes and Exome Sequencing Projects to a spectrum of populations representing the wide range of West African genomic diversity. These individuals from CAAPA also comprise a large swath of the African Diaspora population and incorporate historical genetic diversity covering nearly the entire Atlantic coast of the Americas. Here we show the results of designing and producing such a microchip array. This novel array covers African specific variation far better than other commercially available arrays, and will enable better GWAS analyses for researchers with individuals of African descent in their study populations. A recent study cataloging variation in continental African populations suggests this type of African-specific genotyping array is both necessary and valuable for facilitating large-scale GWAS in populations of African ancestry.

The African Genome Variation Project shapes medical genetics in Africa

Science.gov (United States)

Gurdasani, Deepti; Carstensen, Tommy; Tekola-Ayele, Fasil; Pagani, Luca; Tachmazidou, Ioanna; Hatzikotoulas, Konstantinos; Karthikeyan, Savita; Iles, Louise; Pollard, Martin O.; Choudhury, Ananyo; Ritchie, Graham R. S.; Xue, Yali; Asimit, Jennifer; Nsubuga, Rebecca N.; Young, Elizabeth H.; Pomilla, Cristina; Kivinen, Katja; Rockett, Kirk; Kamali, Anatoli; Doumatey, Ayo P.; Asiki, Gershim; Seeley, Janet; Sisay-Joof, Fatoumatta; Jallow, Muminatou; Tollman, Stephen; Mekonnen, Ephrem; Ekong, Rosemary; Oljira, Tamiru; Bradman, Neil; Bojang, Kalifa; Ramsay, Michele; Adeyemo, Adebowale; Bekele, Endashaw; Motala, Ayesha; Norris, Shane A.; Pirie, Fraser; Kaleebu, Pontiano; Kwiatkowski, Dominic; Tyler-Smith, Chris; Rotimi, Charles; Zeggini, Eleftheria; Sandhu, Manjinder S.

2015-01-01

Given the importance of Africa to studies of human origins and disease susceptibility, detailed characterization of African genetic diversity is needed. The African Genome Variation Project provides a resource with which to design, implement and interpret genomic studies in sub-Saharan Africa and worldwide. The African Genome Variation Project represents dense genotypes from 1,481 individuals and whole-genome sequences from 320 individuals across sub-Saharan Africa. Using this resource, we find novel evidence of complex, regionally distinct hunter-gatherer and Eurasian admixture across sub-Saharan Africa. We identify new loci under selection, including loci related to malaria susceptibility and hypertension. We show that modern imputation panels (sets of reference genotypes from which unobserved or missing genotypes in study sets can be inferred) can identify association signals at highly differentiated loci across populations in sub-Saharan Africa. Using whole-genome sequencing, we demonstrate further improvements in imputation accuracy, strengthening the case for large-scale sequencing efforts of diverse African haplotypes. Finally, we present an efficient genotype array design capturing common genetic variation in Africa.

The African Genome Variation Project shapes medical genetics in Africa.

Science.gov (United States)

Gurdasani, Deepti; Carstensen, Tommy; Tekola-Ayele, Fasil; Pagani, Luca; Tachmazidou, Ioanna; Hatzikotoulas, Konstantinos; Karthikeyan, Savita; Iles, Louise; Pollard, Martin O; Choudhury, Ananyo; Ritchie, Graham R S; Xue, Yali; Asimit, Jennifer; Nsubuga, Rebecca N; Young, Elizabeth H; Pomilla, Cristina; Kivinen, Katja; Rockett, Kirk; Kamali, Anatoli; Doumatey, Ayo P; Asiki, Gershim; Seeley, Janet; Sisay-Joof, Fatoumatta; Jallow, Muminatou; Tollman, Stephen; Mekonnen, Ephrem; Ekong, Rosemary; Oljira, Tamiru; Bradman, Neil; Bojang, Kalifa; Ramsay, Michele; Adeyemo, Adebowale; Bekele, Endashaw; Motala, Ayesha; Norris, Shane A; Pirie, Fraser; Kaleebu, Pontiano; Kwiatkowski, Dominic; Tyler-Smith, Chris; Rotimi, Charles; Zeggini, Eleftheria; Sandhu, Manjinder S

2015-01-15

Given the importance of Africa to studies of human origins and disease susceptibility, detailed characterization of African genetic diversity is needed. The African Genome Variation Project provides a resource with which to design, implement and interpret genomic studies in sub-Saharan Africa and worldwide. The African Genome Variation Project represents dense genotypes from 1,481 individuals and whole-genome sequences from 320 individuals across sub-Saharan Africa. Using this resource, we find novel evidence of complex, regionally distinct hunter-gatherer and Eurasian admixture across sub-Saharan Africa. We identify new loci under selection, including loci related to malaria susceptibility and hypertension. We show that modern imputation panels (sets of reference genotypes from which unobserved or missing genotypes in study sets can be inferred) can identify association signals at highly differentiated loci across populations in sub-Saharan Africa. Using whole-genome sequencing, we demonstrate further improvements in imputation accuracy, strengthening the case for large-scale sequencing efforts of diverse African haplotypes. Finally, we present an efficient genotype array design capturing common genetic variation in Africa.

Learning-by-Exporting Versus Self-Selection: New Evidence for 19 Sub-Saharan African Countries

NARCIS (Netherlands)

Foster-McGregor, N.; Isaksson, A.; Kaulich, F.

2015-01-01

We examine learning-by-exporting effects of manufacturing and services firms in 19 sub-Saharan African countries. Comparing several outlier-robust estimators, our results provide evidence for positive effects in the manufacturing sector when using the MM estimator, but not in the services sector.

Vectorcardiogram of the 'Man-Frog' | Skowron | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 47, No 6 (1973) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Iron(III) biosorption by Polyporus squamosus | Razmovski | African ...

African Journals Online (AJOL)

African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 7, No 11 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Children and Modern Day Slavery | Okpalaobi | African Research ...

African Journals Online (AJOL)

African Research Review. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 10, No 1 (2016) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

From trauma to resilience | Christensen | African Health Sciences

African Journals Online (AJOL)

African Health Sciences. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 8 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if ...

Awareness of Kidney Disorders in Nigeria | Alebiosu | African ...

African Journals Online (AJOL)

African Journal of Health Sciences. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 9, No 2 (2002) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Human Cryptosporidiosis: A Review | Ayuo | East African Medical ...

African Journals Online (AJOL)

East African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 86, No 2 (2009) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Adhesive intestinal obstruction | Kuremu | East African Medical Journal

African Journals Online (AJOL)

East African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 83, No 6 (2006) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Aphasia, an acquired language disor | Schoeman | South African ...

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 52, No 4 (2010) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Diagnosis and treatment of endometriosis | Mounsey | South African ...

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 49, No 3 (2007) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Flat Foot II | Dommisse | South African Medical Journal

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 45, No 7 (1971) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Modern management of colorectal cancer | Baigrie | South African ...

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 55, No 1 (2013) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Nightmares and sleep terrors | Scribante | South African Family ...

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 49, No 6 (2007) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Studies on arbuscular mycorrhisation of papaya | Khade | African ...

African Journals Online (AJOL)

African Crop Science Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 17, No 3 (2009) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Editorial : Emerging issues of measles | Obimbo | East African ...

African Journals Online (AJOL)

East African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 78, No 1 (2001) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Paediatric vaginal discharge | Makwela | South African Family Practice

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 49, No 7 (2007) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Proton-pump inhibitors | Naidoo | South African Family Practice

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 57, No 3 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Giant vesical calculus | Laubscher | South African Medical Journal

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 68, No 6 (1983) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Biosafety regulations in Brazil | Sampaio | African Crop Science ...

African Journals Online (AJOL)

African Crop Science Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 3, No 3 (1995) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Design of the Lifestyle Improvement through Food and Exercise (LIFE) study: a randomized controlled trial of self-management of type 2 diabetes among African American patients from safety net health centers.

Science.gov (United States)

Lynch, Elizabeth B; Liebman, Rebecca; Ventrelle, Jennifer; Keim, Kathryn; Appelhans, Bradley M; Avery, Elizabeth F; Tahsin, Bettina; Li, Hong; Shapera, Merle; Fogelfeld, Leon

2014-11-01

The Lifestyle Improvement through Food and Exercise (LIFE) study is a community-based randomized-controlled trial to measure the effectiveness of a lifestyle intervention to improve glycemic control among African Americans with type 2 diabetes attending safety net clinics. The study enrolled African American adults with a diagnosis of type 2 diabetes and HbA1c ≥ 7.0 who had attended specific safety net community clinics in the prior year. 210 patients will be enrolled and randomized to either the LIFE intervention or a standard of care control group, which consists of two dietitian-led diabetes self-management classes. The LIFE intervention was delivered in 28 group sessions over 12 months and focused on improving diet through dietitian-led culturally-tailored nutrition education, increasing physical activity through self-monitoring using an accelerometer, increasing ability to manage blood sugar through modifications to lifestyle, and providing social support for behavior change. In addition to the group sessions, peer supporters made regular telephone calls to participants to monitor progress toward behavioral goals and provide social support. The 12-month intervention phase was followed by a six-month maintenance phase consisting of two group sessions. The primary outcome of the study is change in A1C from baseline to 12 months, and an additional follow-up will occur at 18 months. The hypothesis of the study is that the participants in the LIFE intervention will show a greater improvement in glycemic control over 12 months than participants in the control group. Copyright © 2014 Elsevier Inc. All rights reserved.

"Project ACTS": An Intervention to Increase Organ and Tissue Donation Intentions among African Americans

Science.gov (United States)

Arriola, Kimberly; Robinson, Dana H.; Thompson, Nancy J.; Perryman, Jennie P.

2010-01-01

This study sought to evaluate the effectiveness of "Project ACTS: About Choices in Transplantation and Sharing," which was developed to increase readiness for organ and tissue donation among African American adults. Nine churches (N = 425 participants) were randomly assigned to receive donation education materials currently available to consumers…

Solid medical waste management in Africa | Udofia | African Journal ...

African Journals Online (AJOL)

Additional articles were included from open google search. Articles were selected for inclusion if they described SMW management activities such as waste segregation, collection, transport (on-site and/or off-site), temporary storage, treatment and final disposal; were located in an African country and were written in English; ...

Contraception for first-time users | Lindeque | South African Family ...

African Journals Online (AJOL)

Contraceptives may also be prescribed for their additional benefits like cycle control and acne and are also used to assist couples to space and plan their families. This article presents value information on the various methods of contraception for product selection and counselling. South African Family Practice Vol.

Two-year Randomized Clinical Trial of Self-etching Adhesives and Selective Enamel Etching.

Science.gov (United States)

Pena, C E; Rodrigues, J A; Ely, C; Giannini, M; Reis, A F

2016-01-01

The aim of this randomized, controlled prospective clinical trial was to evaluate the clinical effectiveness of restoring noncarious cervical lesions with two self-etching adhesive systems applied with or without selective enamel etching. A one-step self-etching adhesive (Xeno V(+)) and a two-step self-etching system (Clearfil SE Bond) were used. The effectiveness of phosphoric acid selective etching of enamel margins was also evaluated. Fifty-six cavities were restored with each adhesive system and divided into two subgroups (n=28; etch and non-etch). All 112 cavities were restored with the nanohybrid composite Esthet.X HD. The clinical effectiveness of restorations was recorded in terms of retention, marginal integrity, marginal staining, caries recurrence, and postoperative sensitivity after 3, 6, 12, 18, and 24 months (modified United States Public Health Service). The Friedman test detected significant differences only after 18 months for marginal staining in the groups Clearfil SE non-etch (p=0.009) and Xeno V(+) etch (p=0.004). One restoration was lost during the trial (Xeno V(+) etch; p>0.05). Although an increase in marginal staining was recorded for groups Clearfil SE non-etch and Xeno V(+) etch, the clinical effectiveness of restorations was considered acceptable for the single-step and two-step self-etching systems with or without selective enamel etching in this 24-month clinical trial.

A comparison of random forest and its Gini importance with standard chemometric methods for the feature selection and classification of spectral data

Directory of Open Access Journals (Sweden)

Himmelreich Uwe

2009-07-01

Full Text Available Abstract Background Regularized regression methods such as principal component or partial least squares regression perform well in learning tasks on high dimensional spectral data, but cannot explicitly eliminate irrelevant features. The random forest classifier with its associated Gini feature importance, on the other hand, allows for an explicit feature elimination, but may not be optimally adapted to spectral data due to the topology of its constituent classification trees which are based on orthogonal splits in feature space. Results We propose to combine the best of both approaches, and evaluated the joint use of a feature selection based on a recursive feature elimination using the Gini importance of random forests' together with regularized classification methods on spectral data sets from medical diagnostics, chemotaxonomy, biomedical analytics, food science, and synthetically modified spectral data. Here, a feature selection using the Gini feature importance with a regularized classification by discriminant partial least squares regression performed as well as or better than a filtering according to different univariate statistical tests, or using regression coefficients in a backward feature elimination. It outperformed the direct application of the random forest classifier, or the direct application of the regularized classifiers on the full set of features. Conclusion The Gini importance of the random forest provided superior means for measuring feature relevance on spectral data, but – on an optimal subset of features – the regularized classifiers might be preferable over the random forest classifier, in spite of their limitation to model linear dependencies only. A feature selection based on Gini importance, however, may precede a regularized linear classification to identify this optimal subset of features, and to earn a double benefit of both dimensionality reduction and the elimination of noise from the classification task.

A randomized pilot study of a community-based weight loss intervention for African-American women: Rationale and study design of Doing Me! Sisters Standing Together for a Healthy Mind and Body.

Science.gov (United States)

Springfield, Sparkle; Buscemi, Joanna; Fitzgibbon, Marian L; Stolley, Melinda R; Zenk, Shannon N; Schiffer, Linda; Sampson, Jameika; Jones, Quiana; Murdock, Tanine; Davis, Iona; Holland, Loys; Watkins, April; Odoms-Young, Angela

2015-07-01

Despite the high prevalence of obesity among African-American women and modest success in behavioral weight loss interventions, the development and testing of weight management interventions using a community-based participatory research (CBPR) approach have been limited. Doing Me!: Sisters Standing Together for Healthy Mind and Body (Doing Me!) is an intervention adapted from an evidence-based behavioral obesity intervention using a CBPR approach. The purpose of Doing Me! is to test the feasibility and acceptability of this adapted intervention and determine its efficacy in achieving improvements in anthropometrics, diet, and physical activity. Sixty African-American women, from a low-income, urban community, aged 30-65 years will be randomized to one of two arms: 16-week Doing Me! (n = 30) or waitlist control (n = 30). Doing Me! employs CBPR methodology to involve community stakeholders and members during the planning, development, implementation, and evaluation phases of the intervention. There will be thirty-two 90-minute sessions incorporating 45 min of instruction on diet, physical activity, and/or weight management plus 45 min of physical activity. Data will be collected at baseline and post-intervention (16 weeks). Doing Me! is one of the first CBPR studies to examine the feasibility/acceptability of an adapted evidence-based behavioral weight loss intervention designed for obese African-American women. CBPR may be an effective strategy for implementing a weight management intervention among this high-risk population. Copyright © 2015 Elsevier Inc. All rights reserved.

Random effect selection in generalised linear models

DEFF Research Database (Denmark)

Denwood, Matt; Houe, Hans; Forkman, Björn

We analysed abattoir recordings of meat inspection codes with possible relevance to onfarm animal welfare in cattle. Random effects logistic regression models were used to describe individual-level data obtained from 461,406 cattle slaughtered in Denmark. Our results demonstrate that the largest...

On the Efficacy and Mediation of a One-on-One HIV Risk-Reduction Intervention for African American Men Who Have Sex with Men: A Randomized Controlled Trial.

Science.gov (United States)

Jemmott, John B; Jemmott, Loretta Sweet; O'Leary, Ann; Icard, Larry D; Rutledge, Scott E; Stevens, Robin; Hsu, Janet; Stephens, Alisa J

2015-07-01

We examined the efficacy and mediation of Being Responsible for Ourselves (BRO), an HIV/STI risk-reduction intervention for African American men who have sex with men (MSM), the population with the highest HIV-diagnosis rate in the US. We randomized African American MSM to one of two interventions: BRO HIV/STI risk-reduction, targeting condom use; or attention-matched control, targeting physical activity and healthy diet. The interventions were based on social cognitive theory, the reasoned-action approach, and qualitative research. Men reporting anal intercourse with other men in the past 90 days were eligible and completed pre-intervention, immediately post-intervention, and 6 and 12 months post-intervention surveys. Of 595 participants, 503 (85 %) completed the 12-month follow-up. Generalized-estimating-equations analysis indicated that, compared with the attention-matched control intervention, the BRO intervention did not increase consistent condom use averaged over the 6- and 12-month follow-ups, which was the primary outcome. Although BRO did not affect the proportion of condom-protected intercourse acts, unprotected sexual intercourse, multiple partners, or insertive anal intercourse, it did reduce receptive anal intercourse compared with the control, a behavior linked to incident HIV infection. Mediation analysis using the product-of-coefficients approach revealed that although BRO increased seven of nine theoretical constructs it was designed to affect, it increased only one of three theoretical constructs that predicted consistent condom use: condom-use impulse-control self-efficacy. Thus, BRO indirectly increased consistent condom use through condom-use impulse-control self-efficacy. In conclusion, although BRO increased several theoretical constructs, most of those constructs did not predict consistent condom use; hence, the intervention did not increase it. Theoretical constructs that interventions should target to increase African American MSM

Standardisation of spirometry | Stewart | South African Medical Journal

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 79, No 4 (1991) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Starting infants on antiretroviral therapy | Clayden | Southern African ...

African Journals Online (AJOL)

Southern African Journal of HIV Medicine. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 9, No 4 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Abandoning weight-loss programmes | Van Staden | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 79, No 5 (1991) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Molecular mechanisms of insulin resistance | Pillay | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 79, No 5 (1991) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Constipation, purgatives or the knife? | Jeppe | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 84, No 12 (1994) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Editorial: Gun control saves lives | Matzopoulos | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 106, No 6 (2016) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Scientific research: The planning process | Gous | South African ...

African Journals Online (AJOL)

South African Journal of Animal Science. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 40, No 5 (2012) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Posterior urethral valves and Down syndrome | Lazarus | African ...

African Journals Online (AJOL)

African Journal of Urology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 21, No 1 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

Intravascular catheter sepsis | Mer | South African Medical Journal

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 89, No 10 (1999) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

African Anthropologist

African Journals Online (AJOL)

PROMOTING ACCESS TO AFRICAN RESEARCH ... It provides a forum for African and Africanist anthropologists to publish research reports, articles, book ... A Qualitative Exploration · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

"Views from the Nano Edge": Women on Doctoral Preparation Programmes in Selected African Contexts

Science.gov (United States)

Williamson, Charmaine

2016-01-01

The study explored the conceptual views of "critical mass", alongside micro experiences, of women, at a practice level, on a doctoral preparation programme which was implemented within the South African Development Community (SADC) and Ethiopian contexts. At the strategising level of policies, insufficient attention has been paid to the…

African Anthropologist: Submissions

African Journals Online (AJOL)

Author Guidelines. The African Anthropologist is a biannual journal of the Pan African Anthropological Association. It provides a forum for African and Africanist anthropologists to publish articles, research reports, review articles, and book reviews. The views expressed in any published material are those of the authors and ...

Yield evaluation and stability analysis in newly selected `KSA' cotton ...

African Journals Online (AJOL)

Yield evaluation and stability analysis in newly selected `KSA' cotton cultivars in Western Kenya. R M Opondo, G A Ombakho. Abstract. (African Crop Science Journal, 1997 5(2): 119-126). http://dx.doi.org/10.4314/acsj.v5i2.27854 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians ...

African Journals Online (AJOL)

African Journals Online (AJOL)

African Journals OnLine (AJOL) is the world's largest and pre-eminent collection of peer-reviewed, African-published scholarly journals. Historically, scholarly information has flowed from North to South and from West to East. It has also been difficult for African researchers to access the work of other African academics.

African Journals Online (AJOL)

African Journals Online (AJOL)

It has also been difficult for African researchers to access the work of other African academics. In partnership with hundreds of journals from all over the continent, AJOL works to change this, so that African-origin research output is available to Africans and ... Featured Country: South Africa, Featured Journal: Ergonomics SA ...

Rhetoric or action: Are South African municipalities planning for climate change?

CSIR Research Space (South Africa)

Faling, W

2012-06-01

Full Text Available In 2008 the South African National Disaster Management Centre commissioned a study into measures taken by local municipalities to plan for climate change. Two areas were selected for their dissimilar climatic challenges: the //Khara Hais...

Long-term effects of the strong African American families program on youths' alcohol use.

Science.gov (United States)

Brody, Gene H; Chen, Yi-Fu; Kogan, Steven M; Murry, Velma McBride; Brown, Anita C

2010-04-01

This report extends earlier accounts by addressing the effects of the Strong African American Families (SAAF) program across 65 months. Two hypotheses were tested: (a) Rural African American youths randomly assigned to participate in SAAF would demonstrate lower rates of alcohol use than would control youths more than 5 years later, and (b) SAAF's effects on deterring the onset of alcohol use in early adolescence would carry forward to mediate the program's long-term effects. African American youths in rural Georgia (mean age at pretest = 10.8 years) were assigned randomly to the SAAF group (n = 369) or to a control group (n = 298). Past-month alcohol use was assessed at pretest and at 9, 18, 29, 53, and 65 months after pretest. SAAF participants increased their alcohol use at a slower rate than did adolescents in the control condition across the follow-up assessments. At the 65-month assessment, SAAF participants reported having drunk alcohol half as often as did youths in the control group. Consistent with the second hypothesis, SAAF's effects on deterring initiation carried forward to account for its effects on alcohol use across time. Training in protective parenting processes and self-regulatory skills during preadolescence may contribute to a self-sustaining trajectory of disinterest in and avoidance of alcohol use during adolescence when peers begin to model and sanction it. (c) 2010 APA, all rights reserved

WISER ranking of the African national libraries' websites | Gupta ...

African Journals Online (AJOL)

... as number of webpages, in-links, rich content files, publications in Google Scholar. It was also found that the website of National Library of South Africa also holds the first rank in WISER among the selected websites of African national libraries. Keywords: National, Libraries, Webometrics, WIF, WISER, Website, evaluation, ...

Fat, Fiber and Cancer Risk in African Americans and Rural Africans

Science.gov (United States)

O'Keefe, Stephen J.D.; Li, Jia V.; Lahti, Leo; Ou, Junhai; Carbonero, Franck; Mohammed, Khaled; Posma, Joram M; Kinross, James; Wahl, Elaine; Ruder, Elizabeth; Vipperla, Kishore; Naidoo, Vasudevan; Mtshali, Lungile; Tims, Sebastian; Puylaert, Philippe G.B.; DeLany, James; Krasinskas, Alyssa; Benefiel, Ann C.; Kaseb, Hatem O.; Newton, Keith; Nicholson, Jeremy K.; de Vos, Willem M.; Gaskins, H. Rex; Zoetendal, Erwin G.

2015-01-01

Rates of colon cancer are much higher in African Americans (65:100,000) than in rural South Africans (<5:100,000). The higher rates are associated with higher animal protein and fat and lower fiber consumption, higher colonic secondary bile acids, lower colonic short chain fatty acid quantities and higher mucosal proliferative biomarkers of cancer risk in otherwise healthy middle aged volunteers. Here we investigate further the role of fat and fiber in this association. We performed two-week food exchanges in subjects from the same populations, where African Americans were fed a high-fiber, lowfat African-style diet, and rural Africans a high-fat low-fiber western-style diet under close supervision. In comparison to their usual diets, the food changes resulted in remarkable reciprocal changes in mucosal biomarkers of cancer risk and in aspects of the microbiota and metabolome known to affect cancer risk, best illustrated by increased saccharolytic fermentation and butyrogenesis and suppressed secondary bile acid synthesis in the African Americans. PMID:25919227

African Journals Online (AJOL)

African Journals Online (AJOL)

It has also been difficult for African researchers to access the work of other African ... search for an article by title, author/s or keywords,; and find other information sources ... Southern African Business Review; The role played by the South African ... The Basis of Distinction Between Qualitative and Quantitative Research in ...

Trends in African philosophy

African Journals Online (AJOL)

JONATHAN

In the contention of Oladipo (2006), the debate on the idea of. African philosophy which has been divided into trends or schools, dates back to the 1960's and 70's, which constitute the modern epoch of African philosophy, when some African thinkers began to question the perspective that traditional African beliefs and.

Blindness and visual impairment in an urban West African population: the Tema Eye Survey.

Science.gov (United States)

Budenz, Donald L; Bandi, Jagadeesh R; Barton, Keith; Nolan, Winifred; Herndon, Leon; Whiteside-de Vos, Julia; Hay-Smith, Graham; Kim, Hanna; Tielsch, James

2012-09-01

To determine the prevalence, causes, and risk factors of blindness and visual impairment among persons aged 40 years or older residing in an urban West African location. Population-based, cross-sectional study. A total of 5603 participants residing in Tema, Ghana. Proportionate random cluster sampling was used to select participants aged 40 years or older living in the city of Tema. Presenting distance visual acuity (VA) was measured at 4 and 1 m using a reduced logarithm of the minimum angle of resolution tumbling E chart and then with trial frame based on autorefraction. A screening examination was performed in the field on all participants. Complete clinical examination by an ophthalmologist was performed on participants with best-corrected visual acuity (BCVA) Tema, Ghana, West Africa. Refractive error is a major cause of blindness and visual impairment in this population, followed by cataract, glaucoma, and corneal disease. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Disentangling the effects of demography and selection in human history.

Science.gov (United States)

Stajich, Jason E; Hahn, Matthew W

2005-01-01

Demographic events affect all genes in a genome, whereas natural selection has only local effects. Using publicly available data from 151 loci sequenced in both European-American and African-American populations, we attempt to distinguish the effects of demography and selection. To analyze large sets of population genetic data such as this one, we introduce "Perlymorphism," a Unix-based suite of analysis tools. Our analyses show that the demographic histories of human populations can account for a large proportion of effects on the level and frequency of variation across the genome. The African-American population shows both a higher level of nucleotide diversity and more negative values of Tajima's D statistic than does a European-American population. Using coalescent simulations, we show that the significantly negative values of the D statistic in African-Americans and the positive values in European-Americans are well explained by relatively simple models of population admixture and bottleneck, respectively. Working within these nonequilibrium frameworks, we are still able to show deviations from neutral expectations at a number of loci, including ABO and TRPV6. In addition, we show that the frequency spectrum of mutations--corrected for levels of polymorphism--is correlated with recombination rate only in European-Americans. These results are consistent with repeated selective sweeps in non-African populations, in agreement with recent reports using microsatellite data.

African Journals Online (AJOL)

African Journals Online (AJOL)

It has also been difficult for African researchers to access the work of other African academics. In partnership with hundreds of journals from all over the continent, AJOL works to change this, so that African-origin research output is available to Africans and to the rest of the ... Egyptian Journal of Medical Human Genetics.

Discrepancy between molecular structure and ligand selectivity of a testicular follicle-stimulating hormone receptor of the African catfish (Clarias gariepinus)

NARCIS (Netherlands)

Bogerd, J.; Blomenröhr, M.; Andersson, E.; van der Putten, H.; Tensen, C.P.; Vischer, H F; Granneman, Joke C M; Janssen-Dommerholt, C; Goos, H.J.; Schulz, Rüdiger W

A putative FSH receptor (FSH-R) cDNA was cloned from African catfish testis. Alignment of the deduced amino acid sequence with other (putative) glycoprotein hormone receptors and analysis of the African catfish gene indicated that the cloned receptor belonged to the FSH receptor subfamily. Catfish

African-American students' perceptions of their majors, future professions, and the dietetics major and profession: a qualitative analysis.

Science.gov (United States)

Felton, Teena M; Nickols-Richardson, Sharon M; Serrano, Elena; Hosig, Kathy W

2008-07-01

African-American professionals are underrepresented in the profession of dietetics. This preliminary qualitative study identified African-American students' perceptions of their majors, future professions, and the dietetics major/profession to understand why they did or did not enter dietetics. It was hypothesized that dietetics students chose dietetics primarily for altruistic reasons, whereas students in other fields of study did not choose dietetics due to lack of awareness of dietetics. To learn students' views, African-American college students engaged in elicitation interviews or focus group discussions. Twenty-eight women and 12 men participated. Phenomenologic analysis identified common themes and meanings: African-American students selected their majors for a variety of reasons, including desire to help people, interest in the field, recommendation from an adult, and family influence. African-American students in fields of study other than dietetics believed that the dietetics major was not selected due to lack of awareness about dietetics. Both dietetics students and students in other fields of study perceived versatility, ability to work with/help people, and to have an influence as positive qualities about their future professions. Advanced degree and training requirements, lack of diversity, and low salary were identified as negative qualities about future professions. African-American students in fields of study other than dietetics had not been exposed to the dietetics major, careers, and profession. Recruitment efforts should begin early to increase the number of African-American students in dietetics.

Random forest variable selection in spatial malaria transmission modelling in Mpumalanga Province, South Africa

Directory of Open Access Journals (Sweden)

Thandi Kapwata

2016-11-01

Full Text Available Malaria is an environmentally driven disease. In order to quantify the spatial variability of malaria transmission, it is imperative to understand the interactions between environmental variables and malaria epidemiology at a micro-geographic level using a novel statistical approach. The random forest (RF statistical learning method, a relatively new variable-importance ranking method, measures the variable importance of potentially influential parameters through the percent increase of the mean squared error. As this value increases, so does the relative importance of the associated variable. The principal aim of this study was to create predictive malaria maps generated using the selected variables based on the RF algorithm in the Ehlanzeni District of Mpumalanga Province, South Africa. From the seven environmental variables used [temperature, lag temperature, rainfall, lag rainfall, humidity, altitude, and the normalized difference vegetation index (NDVI], altitude was identified as the most influential predictor variable due its high selection frequency. It was selected as the top predictor for 4 out of 12 months of the year, followed by NDVI, temperature and lag rainfall, which were each selected twice. The combination of climatic variables that produced the highest prediction accuracy was altitude, NDVI, and temperature. This suggests that these three variables have high predictive capabilities in relation to malaria transmission. Furthermore, it is anticipated that the predictive maps generated from predictions made by the RF algorithm could be used to monitor the progression of malaria and assist in intervention and prevention efforts with respect to malaria.

Selecting Optimal Parameters of Random Linear Network Coding for Wireless Sensor Networks

DEFF Research Database (Denmark)

Heide, J; Zhang, Qi; Fitzek, F H P

2013-01-01

This work studies how to select optimal code parameters of Random Linear Network Coding (RLNC) in Wireless Sensor Networks (WSNs). With Rateless Deluge [1] the authors proposed to apply Network Coding (NC) for Over-the-Air Programming (OAP) in WSNs, and demonstrated that with NC a significant...... reduction in the number of transmitted packets can be achieved. However, NC introduces additional computations and potentially a non-negligible transmission overhead, both of which depend on the chosen coding parameters. Therefore it is necessary to consider the trade-off that these coding parameters...... present in order to obtain the lowest energy consumption per transmitted bit. This problem is analyzed and suitable coding parameters are determined for the popular Tmote Sky platform. Compared to the use of traditional RLNC, these parameters enable a reduction in the energy spent per bit which grows...

Using African languages for democracy and lifelong learning in Africa: A post-2015 challenge and the work of CASAS

Science.gov (United States)

Brock-Utne, Birgit; Mercer, Malcolm

2014-12-01

Africans speak African languages in their everyday lives while lessons in school are delivered in an exogenous language. In many places adult education is also carried out in a language the majority of people do not speak. The exogenous languages, which are the languages of the former colonial powers and mastered just by a small African elite, are used in most parliaments in Africa and in most newspapers. This problem is largely ignored by the international community. An argument often put forward against using African languages as Languages of Instruction (LOIs) is that there are so many of them, and it may be problematic to select one as an LOI. But is this really the case? And does one need to select one language? The main work of the Centre for Advanced Studies of African Society (CASAS) located in Cape Town has been to harmonise the written forms of most African languages so that these languages can be used as LOIs and as languages of government and the press. This paper examines in some detail the work undertaken by CASAS, its successes and challenges. It shows that the political process of getting the harmonised languages adopted is more difficult and unpredictable than the linguistic work itself.

African American Diaspora

Directory of Open Access Journals (Sweden)

Angela Brown

2013-05-01

Full Text Available The migration of blacks in North America through slavery became united.  The population of blacks past downs a tradition of artist through art to native born citizens. The art tradition involved telling stories to each generation in black families. The black culture elevated by tradition created hope to determine their personal freedom to escape from poverty of enslavement and to establish a way of life through tradition. A way of personal freedoms was through getting a good education that lead to a better foundation and a better way of life. With regard to all historic migrations (forced and voluntary, the African Union defined the African diaspora as "[consisting] of people of African origin living outside the continent, irrespective of their citizenship and nationality and who are willing to contribute to the development of the continent and the building of the African Union." Its constitutive act declares that it shall "invite and encourage the full participation of the African diaspora as an important part of our continent, in the building of the African Union."

Extension systems in Southern African countries: A review | Oladele ...

African Journals Online (AJOL)

This paper reviews extension systems in selected southern African countries with a view of identifying the features of the systems and how they have been able to reach their target audience. Some of the features are use of committees for research and extension linkages, involvement of NGOs and private sector, the use ...

The Dictionary Unit for South African English. South African Concise Oxford Dictionary

Directory of Open Access Journals (Sweden)

Rajend Mesthrie

2011-10-01

Full Text Available The South African Concise Oxford Dictionary (henceforth SACOD is a South Af-rican version of the Concise Oxford Dictionary, the first time that this particular hybrid has been prepared. It is testimony to the enduring success of the work of the Dictionary Unit for South African English at Rhodes University, headed by teams that included Jean and William Branford in the 1970s, Penny Silva in the 1990s and now, Kathryn Kavanagh. The lexicographical work from the unit saw the publication of four editions of the Dictionary of Southern African English (1978, 1980, 1987, 1991, a South African Pocket Oxford Dictionary (SAPOD and the Dictionary of South African English on Historical Principles (DOSAEHP (1995. SACOD differs from the rest in several ways. It is larger in scope than SAPOD, smaller than DOSAEHP, and unlike DOSAE and DOSAEHP, does not deal with South African words alone. Based on the 10th edition of the Concise Oxford Dictionary SACOD has excised some words from the parent, whilst adding many new words of general English as well as of South Africa.

Application of random coherence order selection in gradient-enhanced multidimensional NMR

International Nuclear Information System (INIS)

Bostock, Mark J.; Nietlispach, Daniel

2016-01-01

Development of multidimensional NMR is essential to many applications, for example in high resolution structural studies of biomolecules. Multidimensional techniques enable separation of NMR signals over several dimensions, improving signal resolution, whilst also allowing identification of new connectivities. However, these advantages come at a significant cost. The Fourier transform theorem requires acquisition of a grid of regularly spaced points to satisfy the Nyquist criterion, while frequency discrimination and acquisition of a pure phase spectrum require acquisition of both quadrature components for each time point in every indirect (non-acquisition) dimension, adding a factor of 2 N -1 to the number of free- induction decays which must be acquired, where N is the number of dimensions. Compressed sensing (CS) ℓ 1 -norm minimisation in combination with non-uniform sampling (NUS) has been shown to be extremely successful in overcoming the Nyquist criterion. Previously, maximum entropy reconstruction has also been used to overcome the limitation of frequency discrimination, processing data acquired with only one quadrature component at a given time interval, known as random phase detection (RPD), allowing a factor of two reduction in the number of points for each indirect dimension (Maciejewski et al. 2011 PNAS 108 16640). However, whilst this approach can be easily applied in situations where the quadrature components are acquired as amplitude modulated data, the same principle is not easily extended to phase modulated (P-/N-type) experiments where data is acquired in the form exp (iωt) or exp (-iωt), and which make up many of the multidimensional experiments used in modern NMR. Here we demonstrate a modification of the CS ℓ 1 -norm approach to allow random coherence order selection (RCS) for phase modulated experiments; we generalise the nomenclature for RCS and RPD as random quadrature detection (RQD). With this method, the power of RQD can be extended

African languages and African studies librarianship: taking a ...

African Journals Online (AJOL)

Most African educational systems are centred on imported languages such as English, French, and Portuguese. The emphasis in national publishing industries on producing books, journals and newspapers overwhelmingly in those tongues is also hard to justify. It is difficult to imagine a future African renaissance that does ...

Does moonlighting influence South African nurses' intention to leave their primary jobs?

Science.gov (United States)

Rispel, Laetitia C; Chirwa, Tobias; Blaauw, Duane

2014-01-01

Staff retention and turnover have risen in prominence in the global discourse on the health workforce. Moonlighting, having a second job in addition to a primary job, has not featured in debates on turnover. This paper examines whether moonlighting is a determinant of South African nurses' intention to leave their primary jobs. During 2010, a one-stage cluster random sample of 80 hospitals was selected in four South African provinces. On the survey day, all nurses working in critical care, theatre, emergency, maternity, and general medical and surgical wards completed a self-administered questionnaire after giving informed consent. In addition to demographic information and information on moonlighting, the questionnaire obtained information on the participants' intention to leave their primary jobs in the 12 months following the survey. A weighted analysis of the survey data was done using STATA(®) 13. Survey participants (n=3,784) were predominantly middle-aged with a mean age of 41.5 (SD±10.4) years. Almost one-third of survey participants (30.9%) indicated that they planned to leave their jobs within 12 months. Intention to leave was higher among the moonlighters (39.5%) compared to non-moonlighters (27.9%; pleave in a multiple logistic regression were moonlighting in the preceding year, nursing category, sector of primary employment, period working at the primary job, and number of children. The odds of intention to leave was 1.40 (95% CI: 1.16-1.69) times higher for moonlighters than for non-moonlighters. The odds ratio of intention to leave was 0.53 (95% CI: 0.42-0.66) for nursing assistants compared to professional nurses and 2.09 (95% CI: 1.49-2.94) for nurses working for a commercial nursing agency compared to those working in the public sector. Moonlighting is a predictor of intention to leave. Both individual and organisational strategies are needed to manage moonlighting and to enhance retention among South African nurses.

Does moonlighting influence South African nurses’ intention to leave their primary jobs?

Directory of Open Access Journals (Sweden)

Laetitia C. Rispel

2014-12-01

Full Text Available Background: Staff retention and turnover have risen in prominence in the global discourse on the health workforce. Moonlighting, having a second job in addition to a primary job, has not featured in debates on turnover. Objective: This paper examines whether moonlighting is a determinant of South African nurses’ intention to leave their primary jobs. Design: During 2010, a one-stage cluster random sample of 80 hospitals was selected in four South African provinces. On the survey day, all nurses working in critical care, theatre, emergency, maternity, and general medical and surgical wards completed a self-administered questionnaire after giving informed consent. In addition to demographic information and information on moonlighting, the questionnaire obtained information on the participants’ intention to leave their primary jobs in the 12 months following the survey. A weighted analysis of the survey data was done using STATA® 13. Results: Survey participants (n=3,784 were predominantly middle-aged with a mean age of 41.5 (SD±10.4 years. Almost one-third of survey participants (30.9% indicated that they planned to leave their jobs within 12 months. Intention to leave was higher among the moonlighters (39.5% compared to non-moonlighters (27.9%; p<0.001. Predictors of intention to leave in a multiple logistic regression were moonlighting in the preceding year, nursing category, sector of primary employment, period working at the primary job, and number of children. The odds of intention to leave was 1.40 (95% CI: 1.16–1.69 times higher for moonlighters than for non-moonlighters. The odds ratio of intention to leave was 0.53 (95% CI: 0.42–0.66 for nursing assistants compared to professional nurses and 2.09 (95% CI: 1.49–2.94 for nurses working for a commercial nursing agency compared to those working in the public sector. Conclusions: Moonlighting is a predictor of intention to leave. Both individual and organisational strategies are

Does moonlighting influence South African nurses’ intention to leave their primary jobs?

Science.gov (United States)

Rispel, Laetitia C.; Chirwa, Tobias; Blaauw, Duane

2014-01-01

Background Staff retention and turnover have risen in prominence in the global discourse on the health workforce. Moonlighting, having a second job in addition to a primary job, has not featured in debates on turnover. Objective This paper examines whether moonlighting is a determinant of South African nurses’ intention to leave their primary jobs. Design During 2010, a one-stage cluster random sample of 80 hospitals was selected in four South African provinces. On the survey day, all nurses working in critical care, theatre, emergency, maternity, and general medical and surgical wards completed a self-administered questionnaire after giving informed consent. In addition to demographic information and information on moonlighting, the questionnaire obtained information on the participants’ intention to leave their primary jobs in the 12 months following the survey. A weighted analysis of the survey data was done using STATA® 13. Results Survey participants (n=3,784) were predominantly middle-aged with a mean age of 41.5 (SD±10.4) years. Almost one-third of survey participants (30.9%) indicated that they planned to leave their jobs within 12 months. Intention to leave was higher among the moonlighters (39.5%) compared to non-moonlighters (27.9%; pleave in a multiple logistic regression were moonlighting in the preceding year, nursing category, sector of primary employment, period working at the primary job, and number of children. The odds of intention to leave was 1.40 (95% CI: 1.16–1.69) times higher for moonlighters than for non-moonlighters. The odds ratio of intention to leave was 0.53 (95% CI: 0.42–0.66) for nursing assistants compared to professional nurses and 2.09 (95% CI: 1.49–2.94) for nurses working for a commercial nursing agency compared to those working in the public sector. Conclusions Moonlighting is a predictor of intention to leave. Both individual and organisational strategies are needed to manage moonlighting and to enhance retention

Job demands, job resources and work engagement of academic staff in South African higher education institutions

Directory of Open Access Journals (Sweden)

S Rothmann

2006-10-01

Full Text Available The objective of this study was to investigate the work engagement of academics in selected South African higher education institutions as well as the impact of job demands and job resources on their work engagement. Stratified random samples (N = 471 were drawn from academic staff in three higher education institutions in South Africa. The Utrecht Work Engagement Scale (UWES and the Job Demands-Resources Scale (JDRS were administered. The results confirmed a two-factor structure of work engagement, consisting of vigour and dedication. Six reliable factors were extracted on the JDRS, namely organisational support, growth opportunities, social support, overload, advancement and job insecurity. Job resources (including organisational support and growth opportunities predicted 26% of the variance in vigour and 38% of the variance in dedication. Job demands (overload impacted on dedication of academics at low and moderate levels of organisational support.

Simulating the epidemiological and economic effects of an African swine fever epidemic in industrialized swine populations

DEFF Research Database (Denmark)

Hisham Beshara Halasa, Tariq; Bøtner, Anette; Mortensen, Sten

2016-01-01

to simulate the spread of ASF virus between domestic swine herds exemplified by the Danish swine population. ASF was simulated to spread via animal movement, low- or medium-risk contacts and local spread. Each epidemic was initiated in a randomly selected herd – either in a nucleus herd, a sow herd......African swine fever (ASF) is a notifiable infectious disease with a considerable impact on animal health and is currently one of the most important emerging diseases of domestic pigs. ASF was introduced into Georgia in 2007 and subsequently spread to the Russian Federation and several Eastern...... European countries. Consequently, there is a non-negligible risk of ASF spread towards Western Europe. Therefore it is important to develop tools to improve our understanding of the spread and control of ASF for contingency planning. A stochastic and dynamic spatial spread model (DTU-DADS) was adjusted...

Social Realism in the African Novel: The South African and East ...

African Journals Online (AJOL)

Although the African novel arose from Europe, the African has used it to explore a different world view; a world where gods and men hold a place together in the affairs of men. But more importantly, the African novel has followed the peculiar history of colonization and decolonization. While the earlier novels depicted the ...

On Random Numbers and Design

Science.gov (United States)

Ben-Ari, Morechai

2004-01-01

The term "random" is frequently used in discussion of the theory of evolution, even though the mathematical concept of randomness is problematic and of little relevance in the theory. Therefore, since the core concept of the theory of evolution is the non-random process of natural selection, the term random should not be used in teaching the…

Gender differences in technology acceptance in selected South African companies: Implications for electronic learning

Directory of Open Access Journals (Sweden)

Willie T. Chinyamurindi

2010-11-01

Research: The objective of this study was to investigate trainees’ acceptance of electronic coursework as an instruction and learning technique in various industries in the South African context. Motivation for the study: A persistent gender imbalance in the South African work-place has been noted to exist chiefly in the Science, Engineering and Technology (SET sectors, areas that have an important bearing on South Africa’s global competitiveness. This study explores how gender imbalance manifests in terms of trainee acceptance of electronic coursework. Research design, approach and method: A cross-sectional survey design was used. A survey was conducted amongst 191 employees in the SET sector. The measuring instrument used was the Technology Acceptance Instrument (TAI and included measures of Computer Self-Efficacy (CSE, Perceived Ease of Use (PEU, Perceived Usefulness (PU and Behavioural Intention to Use (BI. Main findings: Women ratings of the TAI to use the electronic coursework were slightly higher than men’s ratings. Multiple regression analyses were also carried out to measure the variation in the level of influence with gender as a predictor variable. The results showed that compared to women, men had a lower salient effect of elements of the TAI, notably, CSE–PU; PU–BI and BI–PEU. However, compared to men, women had a higher salient effect in terms of the relationship between CSE–PU and PU–PEU. Practical implications: The implication of the results is that interventions that focus on the human resources development of employees using electronic coursework (namely, CSE, PEU, PU and BI are worth considering as they influence the acceptance of the interventions. Contribution/value-add: The study contributes to existing knowledge about the conditions that precede employee acceptance of an electronic coursework intervention within the South African context. The study shows the important role dimensions of the Technology Acceptance Instrument

Selective inflammatory pain insensitivity in the African naked mole-rat (Heterocephalus glaber).

Science.gov (United States)

Park, Thomas J; Lu, Ying; Jüttner, René; Smith, Ewan St J; Hu, Jing; Brand, Antje; Wetzel, Christiane; Milenkovic, Nevena; Erdmann, Bettina; Heppenstall, Paul A; Laurito, Charles E; Wilson, Steven P; Lewin, Gary R

2008-01-01

In all mammals, tissue inflammation leads to pain and behavioral sensitization to thermal and mechanical stimuli called hyperalgesia. We studied pain mechanisms in the African naked mole-rat, an unusual rodent species that lacks pain-related neuropeptides (e.g., substance P) in cutaneous sensory fibers. Naked mole-rats show a unique and remarkable lack of pain-related behaviors to two potent algogens, acid and capsaicin. Furthermore, when exposed to inflammatory insults or known mediators, naked mole-rats do not display thermal hyperalgesia. In contrast, naked mole-rats do display nocifensive behaviors in the formalin test and show mechanical hyperalgesia after inflammation. Using electrophysiology, we showed that primary afferent nociceptors in naked mole-rats are insensitive to acid stimuli, consistent with the animal's lack of acid-induced behavior. Acid transduction by sensory neurons is observed in birds, amphibians, and fish, which suggests that this tranduction mechanism has been selectively disabled in the naked mole-rat in the course of its evolution. In contrast, nociceptors do respond vigorously to capsaicin, and we also show that sensory neurons express a transient receptor potential vanilloid channel-1 ion channel that is capsaicin sensitive. Nevertheless, the activation of capsaicin-sensitive sensory neurons in naked mole-rats does not produce pain-related behavior. We show that capsaicin-sensitive nociceptors in the naked mole-rat are functionally connected to superficial dorsal horn neurons as in mice. However, the same nociceptors are also functionally connected to deep dorsal horn neurons, a connectivity that is rare in mice. The pain biology of the naked mole-rat is unique among mammals, thus the study of pain mechanisms in this unusual species can provide major insights into what constitutes "normal" mammalian nociception.

Selective inflammatory pain insensitivity in the African naked mole-rat (Heterocephalus glaber.

Directory of Open Access Journals (Sweden)

Thomas J Park

2008-01-01

Full Text Available In all mammals, tissue inflammation leads to pain and behavioral sensitization to thermal and mechanical stimuli called hyperalgesia. We studied pain mechanisms in the African naked mole-rat, an unusual rodent species that lacks pain-related neuropeptides (e.g., substance P in cutaneous sensory fibers. Naked mole-rats show a unique and remarkable lack of pain-related behaviors to two potent algogens, acid and capsaicin. Furthermore, when exposed to inflammatory insults or known mediators, naked mole-rats do not display thermal hyperalgesia. In contrast, naked mole-rats do display nocifensive behaviors in the formalin test and show mechanical hyperalgesia after inflammation. Using electrophysiology, we showed that primary afferent nociceptors in naked mole-rats are insensitive to acid stimuli, consistent with the animal's lack of acid-induced behavior. Acid transduction by sensory neurons is observed in birds, amphibians, and fish, which suggests that this tranduction mechanism has been selectively disabled in the naked mole-rat in the course of its evolution. In contrast, nociceptors do respond vigorously to capsaicin, and we also show that sensory neurons express a transient receptor potential vanilloid channel-1 ion channel that is capsaicin sensitive. Nevertheless, the activation of capsaicin-sensitive sensory neurons in naked mole-rats does not produce pain-related behavior. We show that capsaicin-sensitive nociceptors in the naked mole-rat are functionally connected to superficial dorsal horn neurons as in mice. However, the same nociceptors are also functionally connected to deep dorsal horn neurons, a connectivity that is rare in mice. The pain biology of the naked mole-rat is unique among mammals, thus the study of pain mechanisms in this unusual species can provide major insights into what constitutes "normal" mammalian nociception.

Patterns of family health history communication among older African American adults.

Science.gov (United States)

Hovick, Shelly R; Yamasaki, Jill S; Burton-Chase, Allison M; Peterson, Susan K

2015-01-01

This qualitative study examined patterns of communication regarding family health history among older African American adults. The authors conducted 5 focus groups and 6 semi-structured interviews with African Americans aged 60 years and older (N = 28). The authors identified 4 distinct patterns of family health history communication: noncommunication, open communication, selective communication (communication restricted to certain people or topics), and one-way communication (communication not reciprocated by younger family members). In general, participants favored open family health history communication, often resulting from desires to change patterns of noncommunication in previous generations regarding personal and family health history. Some participants indicated that they were selective about what and with whom they shared health information in order to protect their privacy and not worry others. Others described family health history communication as one-way or unreciprocated by younger family members who appeared uninterested or unwilling to share personal and family health information. The communication patterns that the authors identified are consistent with communication privacy management theory and with findings from studies focused on genetic testing results for hereditary conditions, suggesting that individuals are consistent in their communication of health and genetic risk information. Findings may guide the development of health message strategies for African Americans to increase family health history communication.

Selecting for Fast Protein-Protein Association As Demonstrated on a Random TEM1 Yeast Library Binding BLIP.

Science.gov (United States)

Cohen-Khait, Ruth; Schreiber, Gideon

2018-04-27

Protein-protein interactions mediate the vast majority of cellular processes. Though protein interactions obey basic chemical principles also within the cell, the in vivo physiological environment may not allow for equilibrium to be reached. Thus, in vitro measured thermodynamic affinity may not provide a complete picture of protein interactions in the biological context. Binding kinetics composed of the association and dissociation rate constants are relevant and important in the cell. Therefore, changes in protein-protein interaction kinetics have a significant impact on the in vivo activity of the proteins. The common protocol for the selection of tighter binders from a mutant library selects for protein complexes with slower dissociation rate constants. Here we describe a method to specifically select for variants with faster association rate constants by using pre-equilibrium selection, starting from a large random library. Toward this end, we refine the selection conditions of a TEM1-β-lactamase library against its natural nanomolar affinity binder β-lactamase inhibitor protein (BLIP). The optimal selection conditions depend on the ligand concentration and on the incubation time. In addition, we show that a second sort of the library helps to separate signal from noise, resulting in a higher percent of faster binders in the selected library. Fast associating protein variants are of particular interest for drug development and other biotechnological applications.

Mandela’s Favourite African Folktales

Directory of Open Access Journals (Sweden)

Carmen Concilio

2014-11-01

Full Text Available In this essay I would like to examine the selection of African tales that Nelson Mandela took care to leave as heritage to the future generations, not only to children, and not only to African children. The fact that a political leader, ex freedom fighter and political prisoner dedicated his time to the collection and editing of stories from all over the African continent to be addressed to new readers as simple entertainment or as educational tools clearly testifies to the great humanity, culture, and open mindedness of one of the most important men of our times. In his most recent autobiographical writing Conversations With Myself, Mandela claimed his double affiliation to both his own indigenous culture as well as to western culture. Moreover, he recalled with affection a dear pastime of his childhood: After supper we would listen enthralled to my mother and sometimes my aunt telling us stories, legends, myths and fables which have come down from countless generations, and all of which tended to stimulate the imagination and contained some valuable moral lesson. (p. 10 Thus, it is not surprising that such a charismatic public figure, as Mandela has been, was also interested in- and worried about- the future survival of a cluster of traditional folktales with their lively, specific and “valuable moral lesson”. It is my intention to verify if there might be a dialogue between the western tradition of folktales where animals are protagonists and speak as anthropomorphic figures and the facets of the African traditions and cultures from which Mandela draws inspiration. Among the critical tools on this topic, Tess Cosslett’s Talking Animals in British Children’s Fiction (2006 seems to provide a useful starting point, together with the latest studies in the volume Dall’ABC a Harry Potter (2011, among others. Moreover, aspects of “orature” will be discussed with reference to the stories chosen by Nelson Mandela. Finally, an attempt

Is there Avocado sunblotch Viroid in Ghana? | Acheampong | African ...

African Journals Online (AJOL)

African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 7, No 20 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Alcoholism and diabetes mellitus: Case report | Otieno | East African ...

African Journals Online (AJOL)

East African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 79, No 2 (2002) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Anorexia nervosa in Kenya | Njenga | East African Medical Journal

African Journals Online (AJOL)

East African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 81, No 4 (2004) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Post-traumatic stress disorder: Case report | Nyamai | East African ...

African Journals Online (AJOL)

East African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 77, No 4 (2000) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Enzymes used in detergents: Lipases | Hasan | African Journal of ...

African Journals Online (AJOL)

African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 9, No 31 (2010) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Multiple sclerosis in South Africa | Modi | South African Medical ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 98, No 5 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Primary breast sarcoma: case report | Hassan | East African Medical ...

African Journals Online (AJOL)

East African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 81, No 7 (2004) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Kaposis sarcoma in a Nairobi Hospital | Onyango | East African ...

African Journals Online (AJOL)

East African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 81, No 3 (2004) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Eating disorders in black South African females | Szabo | South ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 85, No 6 (1995) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Mycology and spoilage of retail cashew nuts | Adebajo | African ...

African Journals Online (AJOL)

African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 2, No 10 (2003) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

On the record: Professor Rachel Jewkes | Gould | South African ...

African Journals Online (AJOL)

South African Crime Quarterly. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 43 (2013) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

The late administration of surfactant | Ballot | South African Medical ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 85, No 7 (1995) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Tension type headaches: a review | Magazi | South African Family ...

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 57, No 1 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Migraine headaches in a nutshell | Schellack | South African Family ...

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 59, No 6 (2017) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Stray dog meat consumption and rabies | Wiwanitkit | African Health ...

African Journals Online (AJOL)

African Health Sciences. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 14, No 3 (2014) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

Harlequin color change in preterm infant | Hamida | Pan African ...

African Journals Online (AJOL)

Pan African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 22, No 1 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Psychiatry in Australia | Kaplan | South African Journal of Psychiatry

African Journals Online (AJOL)

South African Journal of Psychiatry. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 10, No 2 (2004) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Intimacy and HIV/Aids | Kasiram | South African Family Practice

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 48, No 2 (2006) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Sexuality in Nigerian older adults | Olatayo | Pan African Medical ...

African Journals Online (AJOL)

Pan African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 22, No 1 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

First-episode psychosis: An update | Chiliza | South African Journal ...

African Journals Online (AJOL)

South African Journal of Psychiatry. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 14, No 1 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Self-concept in overweight adolescents | Pisk | South African Journal ...

African Journals Online (AJOL)

South African Journal of Psychiatry. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 18, No 1 (2012) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Distraction-related road traffic collisions | Eid | African Health Sciences

African Journals Online (AJOL)

African Health Sciences. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 17, No 2 (2017) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

Evaluation of waist-to-height ratio to predict 5 year cardiometabolic risk in sub-Saharan African adults.

Science.gov (United States)

Ware, L J; Rennie, K L; Kruger, H S; Kruger, I M; Greeff, M; Fourie, C M T; Huisman, H W; Scheepers, J D W; Uys, A S; Kruger, R; Van Rooyen, J M; Schutte, R; Schutte, A E

2014-08-01

Simple, low-cost central obesity measures may help identify individuals with increased cardiometabolic disease risk, although it is unclear which measures perform best in African adults. We aimed to: 1) cross-sectionally compare the accuracy of existing waist-to-height ratio (WHtR) and waist circumference (WC) thresholds to identify individuals with hypertension, pre-diabetes, or dyslipidaemia; 2) identify optimal WC and WHtR thresholds to detect CVD risk in this African population; and 3) assess which measure best predicts 5-year CVD risk. Black South Africans (577 men, 942 women, aged >30years) were recruited by random household selection from four North West Province communities. Demographic and anthropometric measures were taken. Recommended diagnostic thresholds (WC > 80 cm for women, >94 cm for men; WHtR > 0.5) were evaluated to predict blood pressure, fasting blood glucose, lipids, and glycated haemoglobin measured at baseline and 5 year follow up. Women were significantly more overweight than men at baseline (mean body mass index (BMI) women 27.3 ± 7.4 kg/m(2), men 20.9 ± 4.3 kg/m(2)); median WC women 81.9 cm (interquartile range 61-103), men 74.7 cm (63-87 cm), all P women, both WC and WHtR significantly predicted all cardiometabolic risk factors after 5 years. In men, even after adjusting WC threshold based on ROC analysis, WHtR better predicted overall 5-year risk. Neither measure predicted hypertension in men. The WHtR threshold of >0.5 appears to be more consistently supported and may provide a better predictor of future cardiometabolic risk in sub-Saharan Africa. Copyright © 2014 Elsevier B.V. All rights reserved.

Obesity and African Americans

Science.gov (United States)

... Data > Minority Population Profiles > Black/African American > Obesity Obesity and African Americans African American women have the ... youthonline . [Accessed 08/18/2017] HEALTH IMPACT OF OBESITY People who are overweight are more likely to ...

Abundance and structure of African baobab (Adansonia digitata) across different soil types in Gonarezhou National Park, Zimbabwe

NARCIS (Netherlands)

Mashapa, C.; Zisadza-Gandiwa, P.; Gandiwa, E.; Kativu, S.

2013-01-01

This study investigated the abundance and structure of African baobab (Adansonia digitata) across soil group strata in Gonarezhou National Park, Zimbabwe. The study was based on a stratified random sampling design composed of the following soil group substrates: (i) granophyres, (ii) malvernia, and

Emotional strain in caregiving among African American grandmothers raising their grandchildren.

Science.gov (United States)

Conway, Francine; Jones, Samuel; Speakes-Lewis, Amandia

2011-01-01

African Americans are disproportionately represented in the number of grandparents raising their grandchildren. Using Role Strain Theory and Socioemotional Selectivity Theory, this study examines how older grandmothers fare relative to their younger counterparts. Eighty-five custodial African American grandmothers, aged 33-88 years old, completed demographic questionnaires and scales of Role Demand, Emotional Strain, Caregiving Strain Index, and Level of Care. Results showed older grandmothers experienced less emotional and caregiving strain relative to younger grandmothers. Furthermore, married grandmothers experienced less caregiving strain, and their age did not insulate them from the strain associated with the level of care. Implications are discussed.

African Zoology

African Journals Online (AJOL)

African Zoology, a peer-reviewed research journal, publishes original scientific contributions and critical reviews that focus principally on African fauna in terrestrial, freshwater, and marine ecosystems. Research from other regions that advances practical and theoretical aspects of zoology will be considered. Rigorous ...

Diabetes awareness among African Americans in rural North Carolina.

Science.gov (United States)

Antony, Angela K; Baaklini, Walid A

2004-01-01

To evaluate the extent of diabetes unawareness in rural North Carolina. Randomly administered an eight-question survey to African Americans age 15-74 living in Halifax County North Carolina. Ninety-five out of 116 eligible participants completed the survey (82% response rate). Most (67%) of the participants reported having two or more major risk factors for Type II diabetes (diabetes mellitus). More than half (51.6%) of the participants were obese. Most (96.8%) of the participants reported having been tested for diabetes at some point in their lives (10% testedpositive, only 8.4% of the remaining 9o% reported ever having a second test). Diabetes mellitus is a very prevalentproblem among the African American population of Halifax County North Carolina. Our study underscores the fact that patients are not systematically screened and followed-up for diabetes melitus. More healthcare and commnity programs need to be adapted to fight this serious public health problem.

Creative Transformation in African Art Music: A Case Study # | Adjei ...

African Journals Online (AJOL)

The study examines and analyses the significance of the style of music composition employing traditional and contemporary models noted in the solo voice and piano works of Nketia. It argues that an imaginative African contemporary composer can elect to work within the limitations of selected traditional instruments and ...

AIDS, order and 'best practice' in the South African workplace ...

African Journals Online (AJOL)

This article examines the response of three medium-sized South African manufacturing companies to HIV/AIDS. It is argued that the response is heavily influenced by managerial conceptions of workplace order — sometimes divergent from industrial realities — which results in the selective inclusion and omission of ...

Staff/population ratios in South African public sector mental health ...

African Journals Online (AJOL)

To document existing staff/population ratios per 100 000 population in South African public sector mental health services. Design. Cross-sectional survey. ... The staff/population ratios per 100 000 population for selected personnel categories (with the interprovincial ranges in brackets) were as follows: total nursing staff 15.6 ...

African Journals Online: Kenya

African Journals Online (AJOL)

Items 1 - 29 of 29 ... African Journal of Food, Agriculture, Nutrition and Development ... African and international non-governmental organizations (NGOs); African and .... for scholars and practitioners in all spheres of biological sciences to publish ...

Directional and balancing selection in human beta-defensins.

Science.gov (United States)

Hollox, Edward J; Armour, John A L

2008-04-16

In primates, infection is an important force driving gene evolution, and this is reflected in the importance of infectious disease in human morbidity today. The beta-defensins are key components of the innate immune system, with antimicrobial and cell signalling roles, but also reproductive functions. Here we examine evolution of beta-defensins in catarrhine primates and variation within different human populations. We show that five beta-defensin genes that do not show copy number variation in humans show evidence of positive selection in catarrhine primates, and identify specific codons that have been under selective pressure. Direct haplotyping of DEFB127 in humans suggests long-term balancing selection: there are two highly diverged haplotype clades carrying different variants of a codon that, in primates, is positively selected. For DEFB132, we show that extensive diversity, including a four-state amino acid polymorphism (valine, isoleucine, alanine and threonine at position 93), is present in hunter-gatherer populations, both African and non-African, but not found in samples from agricultural populations. Some, but not all, beta-defensin genes show positive selection in catarrhine primates. There is suggestive evidence of different selective pressures on these genes in humans, but the nature of the selective pressure remains unclear and is likely to differ between populations.

Heart Disease and African Americans

Science.gov (United States)

... Minority Population Profiles > Black/African American > Heart Disease Heart Disease and African Americans Although African American adults are ... were 30 percent more likely to die from heart disease than non-Hispanic whites. African American women are ...

Dietary adequacies among South African adults in rural KwaZulu-Natal.

Directory of Open Access Journals (Sweden)

Fariba Kolahdooz

Full Text Available BACKGROUND: Food quality, determined by micronutrient content, is a stronger determinant of nutritional status than food quantity. Health concerns resulting from the co-existence of over-nutrition and under-nutrition in low income populations in South Africa have been fully recognized in the last two decades. This study aimed to further investigate dietary adequacy amongst adults in rural KwaZulu-Natal, by determining daily energy and nutrient intakes, and identifying the degree of satisfaction of dietary requirements. METHODS: Cross-sectional study assessing dietary adequacy from 24-hour dietary recalls of randomly selected 136 adults in Empangeni, KwaZulu-Natal, South Africa. RESULTS: Results are presented for men (n = 52 and women (n = 84 19-50 and >50 years old. Mean energy intake was greatest in women >50 years (2852 kcal/day and exceeded Dietary Reference Intake's for both men and women, regardless of age. Mean daily energy intake from carbohydrates was 69% for men and 67% for women, above the Dietary Reference Intake range of 45-65%. Sodium was also consumed in excess, and the Dietary Reference Intakes of vitamins A, B12, C, D, and E, calcium, zinc and pantothenic acid were not met by the majority of the population. CONCLUSION: Despite mandatory fortification of staple South African foods, micronutrient inadequacies are evident among adults in rural South African communities. Given the excess caloric intake and the rising prevalence of obesity and other non-communicable diseases in South Africa, a focus on diet quality may be a more effective approach to influence micronutrient status than a focus on diet quantity.

The African Political Organisation's contributions to South African ...

African Journals Online (AJOL)

The history of South African sport remains an under researched area. According to the historian, Ander Odendaal, the racist nature of 20th Century South African society implies that there are “past exclusions that persist” (Odendaal, 2006:27) In order to address this situation, a scientifichistorical enquiry into the publications ...

Endotypes of difficult-to-control asthma in inner-city African American children.

Directory of Open Access Journals (Sweden)

K R Brown

Full Text Available African Americans have higher rates of asthma prevalence, morbidity, and mortality in comparison with other racial groups. We sought to characterize endotypes of childhood asthma severity in African American patients in an inner-city pediatric asthma population. Baseline blood neutrophils, blood eosinophils, and 38 serum cytokine levels were measured in a sample of 235 asthmatic children (6-17 years enrolled in the NIAID (National Institute of Allergy and Infectious Diseases-sponsored Asthma Phenotypes in the Inner City (APIC study (ICAC (Inner City Asthma Consortium-19. Cytokines were quantified using a MILLIPLEX panel and analyzed on a Luminex analyzer. Patients were classified as Easy-to-Control or Difficult-to-Control based on the required dose of controller medications over one year of prospective management. A multivariate variable selection procedure was used to select cytokines associated with Difficult-to-Control versus Easy-to-Control asthma, adjusting for age, sex, blood eosinophils, and blood neutrophils. In inner-city African American children, 12 cytokines were significant predictors of Difficult-to-Control asthma (n = 235. CXCL-1, IL-5, IL-8, and IL-17A were positively associated with Difficult-to-Control asthma, while IL-4 and IL-13 were positively associated with Easy-to-Control asthma. Using likelihood ratio testing, it was observed that in addition to blood eosinophils and neutrophils, serum cytokines improved the fit of the model. In an inner-city pediatric population, serum cytokines significantly contributed to the definition of Difficult-to-Control asthma endotypes in African American children. Mixed responses characterized by TH2 (IL-5 and TH17-associated cytokines were associated with Difficult-to-Control asthma. Collectively, these data may contribute to risk stratification of Difficult-to-Control asthma in the African American population.

A Permutation Importance-Based Feature Selection Method for Short-Term Electricity Load Forecasting Using Random Forest

Directory of Open Access Journals (Sweden)

Nantian Huang

2016-09-01

Full Text Available The prediction accuracy of short-term load forecast (STLF depends on prediction model choice and feature selection result. In this paper, a novel random forest (RF-based feature selection method for STLF is proposed. First, 243 related features were extracted from historical load data and the time information of prediction points to form the original feature set. Subsequently, the original feature set was used to train an RF as the original model. After the training process, the prediction error of the original model on the test set was recorded and the permutation importance (PI value of each feature was obtained. Then, an improved sequential backward search method was used to select the optimal forecasting feature subset based on the PI value of each feature. Finally, the optimal forecasting feature subset was used to train a new RF model as the final prediction model. Experiments showed that the prediction accuracy of RF trained by the optimal forecasting feature subset was higher than that of the original model and comparative models based on support vector regression and artificial neural network.

The African Genome Variation Project shapes medical genetics in Africa

Science.gov (United States)

Gurdasani, Deepti; Carstensen, Tommy; Tekola-Ayele, Fasil; Pagani, Luca; Tachmazidou, Ioanna; Hatzikotoulas, Konstantinos; Karthikeyan, Savita; Iles, Louise; Pollard, Martin O.; Choudhury, Ananyo; Ritchie, Graham R. S.; Xue, Yali; Asimit, Jennifer; Nsubuga, Rebecca N.; Young, Elizabeth H.; Pomilla, Cristina; Kivinen, Katja; Rockett, Kirk; Kamali, Anatoli; Doumatey, Ayo P.; Asiki, Gershim; Seeley, Janet; Sisay-Joof, Fatoumatta; Jallow, Muminatou; Tollman, Stephen; Mekonnen, Ephrem; Ekong, Rosemary; Oljira, Tamiru; Bradman, Neil; Bojang, Kalifa; Ramsay, Michele; Adeyemo, Adebowale; Bekele, Endashaw; Motala, Ayesha; Norris, Shane A.; Pirie, Fraser; Kaleebu, Pontiano; Kwiatkowski, Dominic; Tyler-Smith, Chris; Rotimi, Charles; Zeggini, Eleftheria; Sandhu, Manjinder S.

2014-01-01

Given the importance of Africa to studies of human origins and disease susceptibility, detailed characterisation of African genetic diversity is needed. The African Genome Variation Project (AGVP) provides a resource to help design, implement and interpret genomic studies in sub-Saharan Africa (SSA) and worldwide. The AGVP represents dense genotypes from 1,481 and whole genome sequences (WGS) from 320 individuals across SSA. Using this resource, we find novel evidence of complex, regionally distinct hunter-gatherer and Eurasian admixture across SSA. We identify new loci under selection, including for malaria and hypertension. We show that modern imputation panels can identify association signals at highly differentiated loci across populations in SSA. Using WGS, we show further improvement in imputation accuracy supporting efforts for large-scale sequencing of diverse African haplotypes. Finally, we present an efficient genotype array design capturing common genetic variation in Africa, showing for the first time that such designs are feasible. PMID:25470054

Retraction | Simon | African Zoology

African Journals Online (AJOL)

Panthera leo) ina. West African national park”. African Zoology is publishing an Editorial Expression of Concern regarding the following article: “New records of a threatened lion population (Panthera leo) in a West African national park” by ...

Streaming weekly soap opera video episodes to smartphones in a randomized controlled trial to reduce HIV risk in young urban African American/black women.

Science.gov (United States)

Jones, Rachel; Lacroix, Lorraine J

2012-07-01

Love, Sex, and Choices is a 12-episode soap opera video series created as an intervention to reduce HIV sex risk. The effect on women's HIV risk behavior was evaluated in a randomized controlled trial in 238 high risk, predominately African American young adult women in the urban Northeast. To facilitate on-demand access and privacy, the episodes were streamed to study-provided smartphones. Here, we discuss the development of a mobile platform to deliver the 12-weekly video episodes or weekly HIV risk reduction written messages to smartphones, including; the technical requirements, development, and evaluation. Popularity of the smartphone and use of the Internet for multimedia offer a new channel to address health disparities in traditionally underserved populations. This is the first study to report on streaming a serialized video-based intervention to a smartphone. The approach described here may provide useful insights in assessing advantages and disadvantages of smartphones to implement a video-based intervention.

Childhood obesity policy: implications for African American girls and a nursing ecological model.

Science.gov (United States)

Reed, Monique

2013-01-01

In the United States there is a prevalence of obesity among ethnic groups, especially African American girls. The author in this column examines through an ecological lens selected American federal, state, and city policies and program interventions aimed at reducing obesity. Specifically, the eating behavior of African American girls is discussed as a population subset for which significant gaps are present in current obesity policy and implementation. Policy recommendations should include parents as research has shown a significant relationship in the eating behaviors of African American girls and their parents. Opportunities for nurses in practice and research to test the effectiveness of family and community level policy and program initiatives that address the ecological perspectives of the adolescent environment are discussed.

Binderless briquetting of some selected South African prime coking, blend coking and weathered bituminous coals and the effect of coal properties on binderless briquetting

Energy Technology Data Exchange (ETDEWEB)

Mangena, S.J. [Division of Mining Technology, CSIR, PO Box 395, Pretoria, 0001 (South Africa); du Cann, V.M. [Coal and Mineral Technologies (Pty) Ltd, SABS, PO Box 73656, Lynnwood Ridge, Pretoria, 0040 (South Africa)

2007-07-02

The binderless briquetting of some selected South African prime coking and blend coking coals, as well as the effects of weathering on the binderless briquetting of some inertinite-rich bituminous coals, were investigated in the laboratory. Selected properties of these coals were determined and the coals were briquetted at various moisture contents and pressures. Based on the results obtained in this study, binderless briquetting was found to be most successful in the cases of the fresh, vitrinite-rich coking and blend coking coals and satisfactory in the fresh inertinite-rich Witbank coals. However, the bonding process seemed to be adversely affected by weathering. The negative impact on bonding could be ameliorated to some extent by the presence of a significant kaolinite content when the percentage ash reports in the order of more than 15% (air-dry basis). It should, however, be noted that kaolinite may reduce the water resistance of the briquettes. (author)

Letters tot he Editor: Authors' response | Chowdhury | South African ...

African Journals Online (AJOL)

South African Journal of Surgery. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 55, No 1 (2017) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Meta-analysis in epidemiology | Yach | South African Medical Journal

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 78, No 7 (1990) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Editorial: Against the tide | Hudson | South African Family Practice

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 49, No 2 (2007) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Eradication of poliomyelitis in South Africa | Blecher | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 84, No 10 (1994) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Ants, rodents and seed predation in Proteaceae | Bond | African ...

African Journals Online (AJOL)

African Zoology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 20, No 3 (1985) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Diagnosis of erectile dysfunction | Raheem | African Journal of Urology

African Journals Online (AJOL)

African Journal of Urology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 15, No 1 (2009) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

Parental care in Hemisus (Anura: Hemisotidae) | van Dijk | African ...

African Journals Online (AJOL)

African Zoology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 32, No 2 (1997) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Kei Apple Plant Thorn Synovitis | Nyamohanga | Annals of African ...

African Journals Online (AJOL)

Annals of African Surgery. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 12, No 2 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

Case Report: Endometriosis of the Appendix | Al Oulaqi | African ...

African Journals Online (AJOL)

African Health Sciences. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 8, No 3 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here ...

Stress and burnout in junior doctors | Schweitzer | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 84, No 6 (1994) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Prostatic fossa calculus | El Abiad | Pan African Medical Journal

African Journals Online (AJOL)

Pan African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 21, No 1 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Snake and staff symbolism, and healing | Retief | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 92, No 7 (2002) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Supplements (Part1): Vitamins | Jobson | South African Family Practice

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 45, No 5 (2003) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Why do elephants flap their ears? | Wright | African Zoology

African Journals Online (AJOL)

African Zoology. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 19, No 4 (1984) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your Web browser ...

Propeller flaps for lower-limb trauma | Rogers | South African ...

African Journals Online (AJOL)

South African Journal of Surgery. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 52, No 4 (2014) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

The current status of psychotherapy | Gureje | West African Journal ...

African Journals Online (AJOL)

West African Journal of Medicine. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 23, No 2 (2004) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Automatic collection of bovine blood samples | Hale | South African ...

African Journals Online (AJOL)

South African Journal of Animal Science. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 4, No 1 (1974) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected ...

Solar retinopathy in Benin City, Nigeria | Ukponmwan | West African ...

African Journals Online (AJOL)

West African Journal of Medicine. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 22, No 4 (2003) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

CPD: The patient with daily headaches. | Maizels | South African ...

African Journals Online (AJOL)

South African Family Practice. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 47, No 10 (2005) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Malaria vector control in South Africa | Brooke | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 103, No 10 (2013) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Social work with refugees in Zimbabwe | Mhlanga | African Journal ...

African Journals Online (AJOL)

African Journal of Social Work. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 6, No 1 (2016) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Adolescence: The age of Proteus | Coovadia | South African Medical ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 106, No 7 (2016) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your ...

Spinal cord injuries in Ilorin, Nigeria | Solagberu | West African ...

African Journals Online (AJOL)

West African Journal of Medicine. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 21, No 3 (2002) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

Direct random insertion mutagenesis of Helicobacter pylori

NARCIS (Netherlands)

de Jonge, Ramon; Bakker, Dennis; van Vliet, Arnoud H. M.; Kuipers, Ernst J.; Vandenbroucke-Grauls, Christina M. J. E.; Kusters, Johannes G.

2003-01-01

Random insertion mutagenesis is a widely used technique for the identification of bacterial virulence genes. Most strategies for random mutagenesis involve cloning in Escherichia coli for passage of plasmids or for phenotypic selection. This can result in biased selection due to restriction or

Direct random insertion mutagenesis of Helicobacter pylori.

NARCIS (Netherlands)

Jonge, de R.; Bakker, D.; Vliet, van AH; Kuipers, E.J.; Vandenbroucke-Grauls, C.M.J.E.; Kusters, J.G.

2003-01-01

Random insertion mutagenesis is a widely used technique for the identification of bacterial virulence genes. Most strategies for random mutagenesis involve cloning in Escherichia coli for passage of plasmids or for phenotypic selection. This can result in biased selection due to restriction or

African Journals Online (AJOL)

African Journals Online (AJOL)

reviewed, African-published scholarly journals. Historically, scholarly information has flowed from North to South and from West to East. It has also been difficult for African researchers to access the work of other African academics. In partnership with ...

African Journals Online (AJOL)

African Journals Online (AJOL)

reviewed, African-published scholarly journals. Historically ... It has also been difficult for African researchers to access the work of other African academics. In partnership with ... Vol 15, No 1 (2018). SAHARA-J: Journal of Social Aspects of HIV/AIDS.

Customer service in appliance sales departments of selected ...

African Journals Online (AJOL)

Customer service in appliance sales departments of selected prominent retail outlets: store manager, ... A single measurement of customers' perception of service quality in various stores however suggested ... AJOL African Journals Online.

Direct and correlated responses to selection for total weight of lamb ...

African Journals Online (AJOL)

The estimated selection responses indicate that direct selection for TWW would be the most suitable selection criterion for improving reproductive performance in flocks with a high reproduction rate where an increase in the number of lambs would be undesirable. (South African Journal of Animal Science, 2001, 31(2): ...

Project SHINE: effects of parent-adolescent communication on sedentary behavior in African American adolescents.

Science.gov (United States)

St George, Sara M; Wilson, Dawn K; Schneider, Elizabeth M; Alia, Kassandra A

2013-10-01

This study examined parenting variables (communication, monitoring) as moderators of a family-based intervention for reducing sedentary behavior (SB) in African American adolescents. As a secondary aim, a similar model was tested using adolescent weight status as the outcome. African American adolescents (n = 73; 12.45 ± 1.45 years; 60% girls; 63% overweight/obese) and caregivers were randomized to a 6-week interactive, parent-based intervention or general health condition. Parent-adolescent communication and monitoring of health behaviors were self-reported by parents. Adolescent SB was self-reported by youth. There was a significant intervention by communication interaction, such that intervention families with more positive communication showed lower adolescent SB than those with less positive communication or those in the comparison condition. No effects were found for monitoring on SB or for the model with weight status as the outcome. Parent-adolescent communication may be an effective component to integrate into health promotion programs for African American adolescents.

Strengthening African Union for African Integration: An African ...

African Journals Online (AJOL)

Toshiba

to secure African continent, speed up development process, and strengthen our survival ... Regional integration generally involves a somewhat complex web of cooperation ... networking of various government institutions to provide and shape.

African American Women's Recollected Experiences of Adherence to Breast Cancer Treatment.

Science.gov (United States)

Heiney, Sue P; Hilfinger Messias, DeAnne K; Felder, Tisha M; Phelps, Kenneth W; Quinn, Jada C

2017-03-01

To explore African American women's recollected experiences of breast cancer treatment.
. Qualitative description and narrative analysis.
. South Carolina Oncology Associates, an outpatient oncology clinic serving rural and urban populations.
. 16 African American women with breast cancer previously enrolled in the control arm (n = 93) of a completed randomized, controlled trial. 
. Feminist narrative analysis of in-depth individual interviews.
. The authors identified three themes within the African American breast cancer survivors' recollected experiences of treatment adherence. Although little evidence was presented of shared decision making with providers, patients were committed to completing the prescribed therapies. The narratives highlighted the value of in-depth examination of patients' perspectives, particularly among minority and underserved groups. With the exception of voicing personal choice of surgical treatment, the women trusted providers' recommendations with a resolve to "just do it." Although trust may enhance treatment adherence, it may also reflect power differentials based on gender, race, education, and culture.
. Nurses should listen to patients describe their experience with cancer treatment and compare the themes from this study with their patients' story. This comparison will help nurses support patients through various aspect of diagnosis and treatment.

Unintended Effects of Emphasizing Disparities in Cancer Communication to African-Americans

OpenAIRE

Nicholson, Robert A.; Kreuter, Matthew W.; Lapka, Christina; Wellborn, Rachel; Clark, Eddie M.; Sanders-Thompson, Vetta; Jacobsen, Heather M.; Casey, Chris

2008-01-01

Little is known about how minority groups react to public information that highlights racial disparities in cancer. This double-blind randomized study compared emotional and behavioral reactions to four versions of the same colon cancer (CRC) information presented in mock news articles to a community sample of African-American adults (n = 300). Participants read one of four articles that varied in their framing and interpretation of race-specific CRC mortality data, emphasizing impact (CRC is...

Understanding the Rise of African Business

DEFF Research Database (Denmark)

Jorem, Kaja Tvedten; Jeppesen, Søren; Hansen, Michael W.

of African firm strategy and performance that takes into account the specificities of the African business environment and African firm capabilities. The paper starts by juxtaposing the widespread pessimistic view of African business with more recent, optimistic studies on African firms’ performance....... The latter suggests that profound improvements in African business performance are indeed under way: with the private sector playing a more important role as an engine of growth, with the rise of a capable African entrepreneurial class, and with the emergence of dynamic and competitive African enterprises...... in the literature, the authors suggest an analytical framework for understanding African business performance, underlining the interplay between contextual specificities, firm capabilities, and firm strategy....

Leadership in the African context

Directory of Open Access Journals (Sweden)

M. Masango

2002-08-01

Full Text Available The Western world has always viewed the African continent as plagued by corruption; dictatorship; military coups; rebellious leaders; greediness; misuse of power; and incompetent, politically unstable leaders - in effect, suspicious leaders who undermine their own democracies. This paper analyzes African leadership and its impact by concentrating on three historical eras, namely; the African Religious era; the Christian era, and the era of Globalization. These affected African leadership. In addition, many brilliant minds left the continent in search of greener pastures. A review of these three eras will help us understand how leadership shifted from African values into Western concepts. The role of missionaries lead African people to live with both an African and a Western concept of life. In spite of the above problems, our past leaders did their best in addressing the difficulties they faced during the three eras. African concepts of leadership were often regarded as barbaric and uncultured. Structures were evaluated by Western standards. Due to globalisation, African leaders, through programmes like NEPAD, are going back to basics, drawing on African concepts of unity among its leadership. Effectiveness or life-giving leadership is emerging and empowering villagers/communities in the continent. This type of leadership is innovative and has brought new hope for the continent.

Molecular detection of salmonella species from selected vegetables ...

African Journals Online (AJOL)

Molecular detection of salmonella species from selected vegetables sold in a north-central ... African Journal of Clinical and Experimental Microbiology ... of the pure isolates testing positive as being pathogenic after biochemical analysis.

Pharmacokinetic and Pharmacodynamic Characteristics of a New Pediatric Formulation of Artemether-Lumefantrine in African Children with Uncomplicated Plasmodium falciparum Malaria▿

OpenAIRE

Djimdé, Abdoulaye A.; Tekete, Mamadou; Abdulla, Salim; Lyimo, John; Bassat, Quique; Mandomando, Inacio; Lefèvre, Gilbert; Borrmann, Steffen

2011-01-01

The pharmacokinetic and pharmacodynamic properties of a new pediatric formulation of artemether-lumefantrine, dispersible tablet, were determined within the context of a multicenter, randomized, parallel-group study. In an exploratory approach, we compared a new pediatric formulation with the tablet formulation administered crushed in the treatment of African children with uncomplicated Plasmodium falciparum malaria. Patients were randomized to 3 different dosing groups (weights of 5 to

Impact of weight-based ribavirin with peginterferon alfa-2b in African Americans with hepatitis C virus genotype 1.

Science.gov (United States)

Jacobson, Ira M; Brown, Robert S; McCone, Jonathan; Black, Martin; Albert, Clive; Dragutsky, Michael S; Siddiqui, Firdous A; Hargrave, Thomas; Kwo, Paul Y; Lambiase, Louis; Galler, Greg W; Araya, Victor; Freilich, Bradley; Harvey, Joann; Griffel, Louis H; Brass, Clifford A

2007-10-01

WIN-R (Weight-based dosing of pegINterferon alfa-2b and Ribavirin) was a multicenter, randomized, open-label, investigator-initiated trial involving 236 community and academic sites in the United States, comparing response to pegylated interferon (PEG-IFN) alfa-2b plus a flat or weight-based dose of ribavirin (RBV) in treatment-naive patients with chronic hepatitis C and compensated liver disease. Patients were randomized to receive PEG-IFN alfa-2b at 1.5 microg/kg/week plus flat-dose (800 mg/day) or weight-based-dose RBV (800 mg/day for weight 85-105 kg, or 1400 mg/day for >105- or =65 kg was the primary end point. Low SVR rates have been reported among African American individuals, in whom there is a preponderance of HCV genotype 1. This subanalysis of WIN-R was conducted to evaluate the efficacy of weight-based dosing among African American individuals with genotype 1 infection enrolled in the trial. Of 362 African American patients in the primary efficacy analysis, 188 received RBV flat dosing and 174 received weight-based dosing. SVR rates were higher (21% versus 10%; P = 0.0006) and relapse rates were lower (22% versus 30%) in the weight-based-dose group than in the flat-dose group. Safety and rates of drug discontinuation were similar between the 2 groups. Weight-based dosing of RBV is more effective than flat dosing in combination with PEG-IFN alfa-2b in African American individuals with HCV genotype 1. Even with weight-based dosing, response rates in African American individuals are lower than reported in other ethnic groups.

African Journals Online (AJOL)

African Journals Online (AJOL)

African Journals OnLine (AJOL) is the world's largest and pre-eminent collection of peer-reviewed, African-published scholarly journals. Historically ... African Research Review; The Roles of Information Communication Technologies in Education: Review Article with Emphasis to the Computer and Internet Ethiopian Journal ...

African Journal on Conflict Resolution

African Journals Online (AJOL)

The African Journal on Conflict Resolution (AJCR) publishes the writings of a wide range of African and international authors in the field, but emphasis has deliberately been kept on African writers and the thinking emerging from African universities, colleges and organisations. Other websites assiciated with this Journal: ...

Selective oropharyngeal decontamination versus selective digestive decontamination in critically ill patients: a meta-analysis of randomized controlled trials

Directory of Open Access Journals (Sweden)

Zhao D

2015-07-01

Full Text Available Di Zhao,1,* Jian Song,2,* Xuan Gao,3 Fei Gao,4 Yupeng Wu,2 Yingying Lu,5 Kai Hou1 1Department of Neurosurgery, The First Hospital of Hebei Medical University, 2Department of Neurosurgery, 3Department of Neurology, The Second Hospital of Hebei Medical University, 4Hebei Provincial Procurement Centers for Medical Drugs and Devices, 5Department of Neurosurgery, The Second Hospital of Hebei Medical University, Shijiazhuang People’s Republic of China *These authors contributed equally to this work Background: Selective digestive decontamination (SDD and selective oropharyngeal decontamination (SOD are associated with reduced mortality and infection rates among patients in intensive care units (ICUs; however, whether SOD has a superior effect than SDD remains uncertain. Hence, we conducted a meta-analysis of randomized controlled trials (RCTs to compare SOD with SDD in terms of clinical outcomes and antimicrobial resistance rates in patients who were critically ill. Methods: RCTs published in PubMed, Embase, and Web of Science were systematically reviewed to compare the effects of SOD and SDD in patients who were critically ill. Outcomes included day-28 mortality, length of ICU stay, length of hospital stay, duration of mechanical ventilation, ICU-acquired bacteremia, and prevalence of antibiotic-resistant Gram-negative bacteria. Results were expressed as risk ratio (RR with 95% confidence intervals (CIs, and weighted mean differences (WMDs with 95% CIs. Pooled estimates were performed using a fixed-effects model or random-effects model, depending on the heterogeneity among studies. Results: A total of four RCTs involving 23,822 patients met the inclusion criteria and were included in this meta-analysis. Among patients whose admitting specialty was surgery, cardiothoracic surgery (57.3% and neurosurgery (29.7% were the two main types of surgery being performed. Pooled results showed that SOD had similar effects as SDD in day-28 mortality (RR =1

Strategyproof Peer Selection using Randomization, Partitioning, and Apportionment

OpenAIRE

Aziz, Haris; Lev, Omer; Mattei, Nicholas; Rosenschein, Jeffrey S.; Walsh, Toby

2016-01-01

Peer review, evaluation, and selection is a fundamental aspect of modern science. Funding bodies the world over employ experts to review and select the best proposals of those submitted for funding. The problem of peer selection, however, is much more general: a professional society may want to give a subset of its members awards based on the opinions of all members; an instructor for a MOOC or online course may want to crowdsource grading; or a marketing company may select ideas from group b...

Globalization and African Political Science | Nnoli | African Journal ...

African Journals Online (AJOL)

No Abstract Available African Journal of Political Science Vol.8(2) 2003: 11-32. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/ajps.v8i2.27352 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors ...

Efficacy of a Weight Loss Intervention for African American Breast Cancer Survivors.

Science.gov (United States)

Stolley, Melinda; Sheean, Patricia; Gerber, Ben; Arroyo, Claudia; Schiffer, Linda; Banerjee, Anjishnu; Visotcky, Alexis; Fantuzzi, Giamila; Strahan, Desmona; Matthews, Lauren; Dakers, Roxanne; Carridine-Andrews, Cynthia; Seligman, Katya; Springfield, Sparkle; Odoms-Young, Angela; Hong, Susan; Hoskins, Kent; Kaklamani, Virginia; Sharp, Lisa

2017-08-20

Purpose African American women with breast cancer have higher cancer-specific and overall mortality rates. Obesity is common among African American women and contributes to breast cancer progression and numerous chronic conditions. Weight loss interventions among breast cancer survivors positively affect weight, behavior, biomarkers, and psychosocial outcomes, yet few target African Americans. This article examines the effects of Moving Forward, a weight loss intervention for African American breast cancer survivors (AABCS) on weight, body composition, and behavior. Patients and Methods Early-stage (I-III) AABCS were randomly assigned to a 6-month interventionist-guided (n = 125) or self-guided (n = 121) weight loss program supporting behavioral changes to promote a 5% weight loss. Anthropometric, body composition, and behavioral data were collected at baseline, postintervention (6 months), and follow-up (12 months). Descriptive statistics and mixed models analyses assessed differences between groups over time. Results Mean (± standard deviation) age, and body mass index were 57.5 (± 10.1) years and 36.1 (± 6.2) kg/m 2 , respectively, and 82% had stage I or II breast cancer. Both groups lost weight. Mean and percentage of weight loss were greater in the guided versus self-guided group (at 6 months: 3.5 kg v 1.3kg; P 3% at 6 months is associated with improved health outcomes. Affordable, accessible health promotion programs represent a critical resource for AABCS.

From Contextual Theology to African Christianity: The Consideration of Adiaphora from a South African Perspective

Directory of Open Access Journals (Sweden)

Joel Mokhoathi

2017-12-01

Full Text Available The move towards contextual Christianity in Africa is an essential venture if Christianity is to communicate with the African cultural heritage. As a universal religion, Christianity has to find an expression within the cultural context. However, the contextualization of Christianity in Africa appears to have permitted the practice of syncretism. It has resulted in the emergence of African Christianity, which is the amalgamation of Christianity and African Traditional Religion. The amalgamation of Christianity and African Traditional Religion appears to overlook the essence of both religions as there is currently no clarity on how Christianity can best be expressed within the African cultural and religious heritage. This paper employs the document review method to explore the things that fall in between—“adiaphora”, which the proponents of contextual Christianity may have overlooked with regard to the African cultural and religious heritage. These include the pragmatic nature of the African cultural and religious heritage, and the African traditional methods of healing.

Male role norms, knowledge, attitudes, and perceptions of colorectal cancer screening among young adult African American men

Directory of Open Access Journals (Sweden)

Charles R. Rogers, Ph.D., CHES

2014-11-01

Full Text Available Racial disparities in health among African American men in the United States are extensive. In contrast to their White counterparts, African American men have more illnesses and die younger. African American men have colorectal cancer (CRC incidence and mortality rates 25% and 50% higher, respectively, than White men. Due to CRC’s younger age at presentation and high incidence among African American men, CRC screening is warranted at the age of 45 rather than 50, but little is known about younger African American men’s views of CRC screening. Employing survey design, the purpose of the study was to describe the male role norms, knowledge, attitudes, perceived subjective norms, and perceived barriers associated with screening for CRC among a non-random sample of 157 young adult African American men (ages 19-45. Sixty-seven percent of the study sample received a passing knowledge score (85% or better, yet no significant differences were found among the three educational levels (i.e., low, medium, high. More negative attitudes towards CRC screening correlated with the participants’ strong perceptions of barriers, but no extremely negative or positive male role norms and perceived subjective norms were found. The factors significantly associated with attitudes were family history of cancer (unsure, work status, and perceived barriers. Findings from this study provide a solid basis for developing structured health education interventions that address the salient factors shaping young adult African American men's view of CRC and early detection screening behaviors.

A proposed quantitative credit-rating methodology for South African provincial departments

Directory of Open Access Journals (Sweden)

Erika Fourie

2016-05-01

Full Text Available The development of subnational credit-rating methodologies affords benefits for subnationals, the sovereign and its citizens. Trusted credit ratings facilitate access to financial markets and above-average ratings allow for the negotiation of better collateral and guarantee agreements, as well as for funding of, for example, infrastructure projects at superior (lower interest rates. This paper develops the quantitative section of a credit-rating methodology for South African subnationals. The unique characteristics of South African data, their assembly, and the selection of dependent and independent variables for the linear-regression model chosen, are discussed. The methodology is then applied to the provincial Department of Health using linear regression modelling.

Paraphilia and sex offending - A South African criminal law perspective.

Science.gov (United States)

Carstens, Pieter; Stevens, Philip

2016-01-01

Historically, the link between sexual deviance and criminality has been described and documented, asserted by psychiatry, and manifested in law. Laws that have regulated sexual behaviour have referred to terms such as 'sexual deviation', 'sexual perversion' or even archaic moral terms such as 'unnatural acts and unspeakable crimes against nature'. A possible link between sexual perversion, psychopathy, and criminality, specifically manifesting in sexual homicide, has been the subject of remarkable research in forensic psychiatry. This contribution examines the phenomenon of paraphilia with specific reference to its definition, diagnostic classification and characteristics, as well as a few selections of incidences of paraphilia in South African criminal case law. A brief assessment is made of how South African criminal courts have dealt with paraphilia. In this regard, an analysis is made of the criminal liability of the paraphiliac. The South African response to sexual deviation as addressed in the Criminal Law (Sexual Offences and Related Matters) Amendment Act 32 of 2007 will also be addressed with reference to its efficacy in addressing paraphilia within South African criminal law. The interface between criminal law and medical ethics within the context of this theme will also be canvassed. In conclusion, recommendations for possible reform are canvassed. Copyright © 2016. Published by Elsevier Ltd.

How Neighborhood Effects Vary: Childbearing and Fathering among Latino and African American Adolescents

Directory of Open Access Journals (Sweden)

Jessica L. Lucero

2018-01-01

Full Text Available This study examines what neighborhood conditions experienced at age 15 and after are associated with teen childbearing and fathering among Latino and African American youth and whether these neighborhood effects vary by gender and/or ethnicity. Administrative and survey data from a natural experiment are used for a sample of 517 Latino and African American youth whose families were quasi-randomly assigned to public housing operated by the Denver (CO Housing Authority (DHA. Characteristics of the neighborhood initially assigned by DHA to wait list applicants are utilized as identifying instruments for the neighborhood contexts experienced during adolescence. Cox Proportional Hazards (PH models reveal that neighborhoods having higher percentages of foreign-born residents but lower levels of social capital robustly predict reduced odds of teen parenting though the magnitude of these effects was contingent on gender and ethnicity. Specifically, the presence of foreign-born neighbors on the risk of teen parenting produced a stronger dampening effect for African American youth when compared to Latino youth. Additionally, the effects of social capital on teen parenting were stronger for males than females.

African Journals Online (AJOL)

African Journals Online (AJOL)

It has also been difficult for African researchers to access the work of other African academics. ... search for an article by title, author/s or keywords,; and find other information ... Southern African Business Review; Project Work by Students for First ... The Basis of Distinction Between Qualitative and Quantitative Research in ...

African Journals Online (AJOL)

African Journals Online (AJOL)

It has also been difficult for African researchers to access the work of other African ... search for an article by title, author/s or keywords,; and find other information ... Southern African Business Review; Effect of Globalization on Sovereignty of States ... The Basis of Distinction Between Qualitative and Quantitative Research in ...

African Journals Online (AJOL)

African Journals Online (AJOL)

It has also been difficult for African researchers to access the work of other African ... search for an article by title, author/s or keywords,; and find other information sources ... Southern African Business Review; Conflicts in Africa: Meaning, Causes, ... The Basis of Distinction Between Qualitative and Quantitative Research in ...