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Sample records for randomly selected african

  1. African Literature: Selected Resources.

    Science.gov (United States)

    Deschenes, Martin O.; Waters, Harold A.

    This bibliography of resources for the teaching of African literature includes over 100 citations of books, textbooks, anthologies, plays, novels, short stories, and periodicals in French and English. Publishing house addresses, audiovisual aids, professional organizations, and a course list are also cited. The books are listed under the following…

  2. Blocked Randomization with Randomly Selected Block Sizes

    Directory of Open Access Journals (Sweden)

    Jimmy Efird

    2010-12-01

    Full Text Available When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of individuals may be assigned to each arm of the study and thus decrease the power to detect statistically significant differences between groups. Block randomization is a commonly used technique in clinical trial design to reduce bias and achieve balance in the allocation of participants to treatment arms, especially when the sample size is small. This method increases the probability that each arm will contain an equal number of individuals by sequencing participant assignments by block. Yet still, the allocation process may be predictable, for example, when the investigator is not blind and the block size is fixed. This paper provides an overview of blocked randomization and illustrates how to avoid selection bias by using random block sizes.

  3. Blocked randomization with randomly selected block sizes.

    Science.gov (United States)

    Efird, Jimmy

    2011-01-01

    When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of individuals may be assigned to each arm of the study and thus decrease the power to detect statistically significant differences between groups. Block randomization is a commonly used technique in clinical trial design to reduce bias and achieve balance in the allocation of participants to treatment arms, especially when the sample size is small. This method increases the probability that each arm will contain an equal number of individuals by sequencing participant assignments by block. Yet still, the allocation process may be predictable, for example, when the investigator is not blind and the block size is fixed. This paper provides an overview of blocked randomization and illustrates how to avoid selection bias by using random block sizes.

  4. Randomized selection on the GPU

    Energy Technology Data Exchange (ETDEWEB)

    Monroe, Laura Marie [Los Alamos National Laboratory; Wendelberger, Joanne R [Los Alamos National Laboratory; Michalak, Sarah E [Los Alamos National Laboratory

    2011-01-13

    We implement here a fast and memory-sparing probabilistic top N selection algorithm on the GPU. To our knowledge, this is the first direct selection in the literature for the GPU. The algorithm proceeds via a probabilistic-guess-and-chcck process searching for the Nth element. It always gives a correct result and always terminates. The use of randomization reduces the amount of data that needs heavy processing, and so reduces the average time required for the algorithm. Probabilistic Las Vegas algorithms of this kind are a form of stochastic optimization and can be well suited to more general parallel processors with limited amounts of fast memory.

  5. Random selection of Borel sets

    Directory of Open Access Journals (Sweden)

    Bernd Günther

    2010-10-01

    Full Text Available A theory of random Borel sets is presented, based on dyadic resolutions of compact metric spaces. The conditional expectation of the intersection of two independent random Borel sets is investigated. An example based on an embedding of Sierpinski’s universal curve into the space of Borel sets is given.

  6. Landmarks of Poetic Renaissance in the Works of Selected African ...

    African Journals Online (AJOL)

    The study is a survey of critical perspectives on a selection of modern African poets who concerned themselves with the socio-political problems in their various local setups and countries. The commonest thing to all of them is the belief and practice in the poet's activist role in the African polity. This group of writers believes ...

  7. The usage of African languages in three selected contemporary ...

    African Journals Online (AJOL)

    ... quantity and function of utterances from three selected contemporary German novels will be presented, in order to show how the use of African languages in these novels can create, perpetuate and resolve suspense in the plot. Keywords: African languages, German novels, Ein Land das Himmel heißt, Die weiße Jägerin, ...

  8. Fluidized bed gasification of selected South African coals

    CSIR Research Space (South Africa)

    Engelbrecht, AD

    2010-05-01

    Full Text Available An investigation was undertaken to ascertain the suitability of four selected low grade, South African coals for gasification in a bubbling fluidized bed for production of synthesis gas and for the development of integrated gasification combined...

  9. Some aspects of gender inequality in selected African literary texts

    OpenAIRE

    L.L. Kwatsha

    2009-01-01

    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 role...

  10. Species selection and random drift in macroevolution.

    Science.gov (United States)

    Chevin, Luis-Miguel

    2016-03-01

    Species selection resulting from trait-dependent speciation and extinction is increasingly recognized as an important mechanism of phenotypic macroevolution. However, the recent bloom in statistical methods quantifying this process faces a scarcity of dynamical theory for their interpretation, notably regarding the relative contributions of deterministic versus stochastic evolutionary forces. I use simple diffusion approximations of birth-death processes to investigate how the expected and random components of macroevolutionary change depend on phenotype-dependent speciation and extinction rates, as can be estimated empirically. I show that the species selection coefficient for a binary trait, and selection differential for a quantitative trait, depend not only on differences in net diversification rates (speciation minus extinction), but also on differences in species turnover rates (speciation plus extinction), especially in small clades. The randomness in speciation and extinction events also produces a species-level equivalent to random genetic drift, which is stronger for higher turnover rates. I then show how microevolutionary processes including mutation, organismic selection, and random genetic drift cause state transitions at the species level, allowing comparison of evolutionary forces across levels. A key parameter that would be needed to apply this theory is the distribution and rate of origination of new optimum phenotypes along a phylogeny. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  11. Improving randomness characterization through Bayesian model selection.

    Science.gov (United States)

    Díaz Hernández Rojas, Rafael; Solís, Aldo; Angulo Martínez, Alí M; U'Ren, Alfred B; Hirsch, Jorge G; Marsili, Matteo; Pérez Castillo, Isaac

    2017-06-08

    Random number generation plays an essential role in technology with important applications in areas ranging from cryptography to Monte Carlo methods, and other probabilistic algorithms. All such applications require high-quality sources of random numbers, yet effective methods for assessing whether a source produce truly random sequences are still missing. Current methods either do not rely on a formal description of randomness (NIST test suite) on the one hand, or are inapplicable in principle (the characterization derived from the Algorithmic Theory of Information), on the other, for they require testing all the possible computer programs that could produce the sequence to be analysed. Here we present a rigorous method that overcomes these problems based on Bayesian model selection. We derive analytic expressions for a model's likelihood which is then used to compute its posterior distribution. Our method proves to be more rigorous than NIST's suite and Borel-Normality criterion and its implementation is straightforward. We applied our method to an experimental device based on the process of spontaneous parametric downconversion to confirm it behaves as a genuine quantum random number generator. As our approach relies on Bayesian inference our scheme transcends individual sequence analysis, leading to a characterization of the source itself.

  12. Biogas technology research in selected sub-Saharan African countries

    African Journals Online (AJOL)

    This reviews aims to provide an insight and update of the state of biogas technology research in some selected sub-Saharan African countries in peer reviewed literature. This paper also aims to highlight the sub-Saharan countries' strengths and weaknesses in biogas research and development capacity. An attempt is ...

  13. South African consumers' selection criteria for ornamental plants: a ...

    African Journals Online (AJOL)

    The considerations of South African consumers in the ornamental plant sector can be interpreted as selection criteria and be used as a marketing tool to increase ... Consumers also value plants' performance attributes such as longevity, a visual statement of good quality, good garden performance, and robust resistance to ...

  14. 32 CFR 1624.1 - Random selection procedures for induction.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Random selection procedures for induction. 1624... SYSTEM INDUCTIONS § 1624.1 Random selection procedures for induction. (a) The Director of Selective Service shall from time to time establish a random selection sequence for induction by a drawing to be...

  15. Project governance: selected South African government experiments

    Directory of Open Access Journals (Sweden)

    G. van der Walt

    2008-07-01

    Full Text Available Some form of accountability and power structure binds all organisations. Such structures are typically referred to as the “governance” structure of the organisation. In organisations that have relatively mature project applications and methodologies in place, governance mechanisms are established on more permanent bases. With its focus on performance, results and outcomes, project governance establishes decision-making structures, as well as accountability and responsibility mechanisms in public institutions to oversee projects. As government institutions increasingly place emphasis on project applications for policy implementation and service delivery initiatives, mechanisms or structures should be established to facilitate clear interfaces between the permanent organisation and the temporary project organisation. Such mechanisms or structures should enhance the governance of projects, that is, the strategic alignment of projects, the decentralisation of decision- making powers, rapid resource allocation, and the participation of external stakeholders. The purpose of this article is to explore the concept “project governance”, and to highlight examples of project governance as applied in selected government departments in provincial and national spheres. This would enable the establishment of best practice examples and assist to develop benchmarks for effective project applications for service delivery improvement.

  16. 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.

  17. Understanding Facilitators and Barriers to the Selection of Dietetics as a major by African American students.

    OpenAIRE

    Felton, Teena M

    2007-01-01

    Understanding Facilitators And Barriers To The Selection of Dietetics As A Major By African-American Students Teena M. Felton (ABSTRACT) Less than 5% of registered dietitians are African-American individuals. Little has been done to investigate reasons for the paucity of African-American professionals in the dietetics field. The specific aim of this study was, therefore, to explore facilitators and barriers to the selection of dietetics as a major by African-American students. ...

  18. Farmer's Knowledge of Horticultural Traits and Participatory Selection of African Eggplant Varieties (Solanum aethiopicum in Tanzania

    Directory of Open Access Journals (Sweden)

    Adeniji, OT.

    2012-01-01

    Full Text Available Participatory selection was conducted in 2008 through 2009 to identify farmers' preference for species and horticultural traits that may constitute future breeding objectives. Vegetable farmers were selected from Moshi and Arusha regions, test population comprised twenty-six accessions from four Solanum species (eggplant and relatives. Purposive sampling was used to select the farming communities with high African eggplant production activities; a multistage random sampling procedure was adopted to select farmers from three regions for participatory meeting. The focus group discussion sessions identified fruit shape, taste, earliness, medicinal properties, marketability and resistance to diseases as farmers' preferred traits in S. aethiopicum; taste and marketability for S. melongena, taste and medicinal properties among S. macrocarpon and S. anguivi. Fruits characterized by cream colour at commercial harvest are most preferred compared to green, to a lesser extent is purple. Interestingly high fruits per plant, fruits per cluster and fruit cluster per plant best described S. anguivi. Fruit yield was superior in Db3 (S. aethiopicum Gilo group, top five accessions for organoleptic properties are Db3, Ab2, MM 1619, S00052 and MM 1086. Characters indicated above may constitute breeding objectives and population identified may serve as pollen parents for development of new varieties in african eggplant. Intraspecific hybridization within S. aethiopicum Gilo cultigroup, hybridization among Gilo and Shum cultigroups and interspecific hybridization between S. aethiopicum and S. anguivi may evolve new population aimed at improving fruit yield.

  19. In-Place Randomized Slope Selection

    DEFF Research Database (Denmark)

    Blunck, Henrik; Vahrenhold, Jan

    2006-01-01

    Slope selection is a well-known algorithmic tool used in the context of computing robust estimators for fitting a line to a collection P of n points in the plane. We demonstrate that it is possible to perform slope selection in expected O(nlogn) time using only constant extra space in addition to...

  20. 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 ...

  1. Attrition of undergraduate nursing students at selected South African universities

    Directory of Open Access Journals (Sweden)

    Erna Roos

    2016-02-01

    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.

  2. Sequential selection of random vectors under a sum constraint

    OpenAIRE

    Stanke, Mario

    2004-01-01

    We observe a sequence X1,X2,...,Xn of independent and identically distributed coordinatewise nonnegative d-dimensional random vectors. When a vector is observed it can either be selected or rejected but once made this decision is final. In each coordinate the sum of the selected vectors must not exceed a given constant. The problem is to find a selection policy that maximizes the expected number of selected vectors. For a general absolutely continuous distribution of t...

  3. 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 ...

  4. Approaches taken by South African advertisers to select and appoint ...

    African Journals Online (AJOL)

    Southern African Business Review Volume 14 Number 1 2010. Approaches taken by South African .... Organisational buying behaviour. Advertising agencies are marketers of business-to-business (B2B) services, and ..... that was exported into SPSS in order to perform statistical analysis. After editing and capturing, the data ...

  5. Coping and work engagement in selected South African organisations

    Directory of Open Access Journals (Sweden)

    Sebastiaan Rothmann

    2011-03-01

    Full Text Available Orientation: The coping strategies of their employees are amongst the activities that organisations should address to improve their employees’ work engagement.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.

  6. Signatures of positive selection in East African Shorthorn Zebu: a genome-wide SNP analysis

    Science.gov (United States)

    The small East African Shorthorn Zebu is the main indigenous cattle across East Africa. A recent genome wide SNPs analysis has revealed their ancient stable African taurine x Asian zebu admixture. Here, we assess the presence of candidate signature of positive selection in their genome, with the aim...

  7. 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.

  8. 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.

  9. Hard boundaries influence African wild dogs' diet and prey selection

    National Research Council Canada - National Science Library

    Davies‐Mostert, Harriet T; Mills, Michael G. L; Macdonald, David W; Dickman, Christopher

    2013-01-01

    Human‐mediated changes in habitat structure may disturb predator–prey relationships. We investigated the influence of perimeter fences on the diet of a reintroduced population of African wild dogs L ycaon pictus T emminck 1820 in a 316...

  10. Measures for diffusion of solar PV in selected African countries

    OpenAIRE

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

    2017-01-01

    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 ...

  11. 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.

  12. Fast, Randomized Join-Order Selection - Why Use Transformations?

    NARCIS (Netherlands)

    C.A. Galindo-Legaria; A.J. Pellenkoft (Jan); M.L. Kersten (Martin)

    1994-01-01

    textabstractWe study the effectiveness of probabilistic selection of join-query evaluation plans, without reliance on tree transformation rules. Instead, each candidate plan is chosen uniformly at random from the space of valid evaluation orders. This leads to a transformation-free strategy where a

  13. 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 ...

  14. The Image of Africa and Africans in selected Anglophone Expatriate ...

    African Journals Online (AJOL)

    ... novelists perception and depiction of Africa as a dark continent, a cursed geographical region infested by deadly animals and Africans as mature devils, half-wits, adult-children and sub-human beings who are bound to violence; and as people who lack comprehensible language, authentic history, workable economic and ...

  15. Talent management: An empirical study of selected South African ...

    African Journals Online (AJOL)

    Southern African Business Review Volume 13 Number 3 2009. Talent management: An empirical study ... of the global gross domestic product (GDP), 12.2% of world exports and 9.5% of world investment (Blanke .... which workforces and areas of business have the greatest strategic impact and are critical in maintaining the ...

  16. Approaches taken by South African advertisers to select and appoint ...

    African Journals Online (AJOL)

    AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use · Contact AJOL · News. OTHER RESOURCES... for Researchers · for Journals · for Authors · for Policy Makers · about Open Access · Journal Quality.

  17. 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 ...

  18. Prevalence rates of six selected infectious diseases among African migrants and refugees: a systematic review and meta-analysis.

    Science.gov (United States)

    Chernet, A; Utzinger, J; Sydow, V; Probst-Hensch, N; Paris, D H; Labhardt, N D; Neumayr, A

    2017-10-28

    The objective of this paper was to systematically review the literature on the prevalence of selected infectious diseases among migrants/refugees of African origin and to provide policy makers and health care professionals with evidence-based information. We pursued a systematic review and meta-analysis to determine the prevalence of six selected infectious diseases (i.e., syphilis, helminthiasis, schistosomiasis, intestinal protozoa infections, hepatitis B, and hepatitis C) among migrants/refugees of African origin. Three electronic databases (i.e., PubMed, EMBASE, and ISI Web of Science) were searched without language restrictions. Relevant data were extracted and random-effects meta-analyses conducted. Only adjusted estimates were analyzed to help account for heterogeneity and potential confounding. We assessed the quality of evidence using the GRADE approach. The results were stratified by geographical region. Ninety-six studies were included. The evidence was of low quality due to the small numbers of countries, infectious diseases, and participants included. African migrants/refugees had median (with 95% confidence interval [95% CI]) prevalence for syphilis, helminthiasis, schistosomiasis, intestinal protozoa infection, hepatitis B, and hepatitis C of 6.0% [95% CI: 2.0-7.0%], 13.0% [95% CI: 9.5-14.5%], 14.0% [95% CI: 13.0-17.0%], 15.0% [95% CI: 10.5-21.0%], 10.0% [95% CI: 6.0-14.0%], and 3.0% [95% CI: 1.0-4.0%], respectively. We found high heterogeneity regardless of the disease (I 2; minimum 97.5%, maximum 99.7%). The relatively high prevalence of some infectious diseases among African migrants/refugees warrants for systematic screening. The large heterogeneity of the available published data does not allow for stratifying such screening programs according to the geographical origin of African migrants/refugees.

  19. 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.

  20. Selecting a phoneme-to-grapheme mapping: Random or weighted selection?

    Directory of Open Access Journals (Sweden)

    Binna Lee

    2015-05-01

    Our findings demonstrate that random selection underestimates MOA’s PG correspondences whereas weighted selection predicts higher PG correspondences than he produces. To explain his intermediate spelling performance on PPEs, we will test additional approaches to weighing the relative probability of PG mappings, including using log frequencies, separating consonant and vowel status, and considering the number of grapheme options in each phoneme.

  1. 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...

  2. Selection for altruism through random drift in variable size populations.

    Science.gov (United States)

    Houchmandzadeh, Bahram; Vallade, Marcel

    2012-05-10

    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. 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. 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.

  3. 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.

  4. 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

  5. PREY SELECTIVITY IN WELS (Silurus glanis AND AFRICAN CATFISH (Clarias gariepinus

    Directory of Open Access Journals (Sweden)

    Zdenek Adamek

    1999-06-01

    Full Text Available The experiments aimed at prey selectivity in two Siluriformes predators. African catfish, Clarias gariepinus, and wels, Silurus glanis, were performed under laboratory conditions. Prey fish (12-22% TL of predator were submitted to one.year.old African catfish (~220 g and wels (~150 g originating from intensive culture, ie with no previous experience with live fish food. In African catfish, negative selectivity (avoidance was shown for Nile tilapia (Oreochromis niloticus and topmouth gudgeon (Pseudorasbora parva whilst rudd(Scardinius erythrophthalmus and sunbleak (Leucaspius delineatus were preferred (positive selectivity. The intensity and efficiency of African catfish predation were quite low because its feeding strategy is based rather on prey searching than hunting. Prey fish, wounded and/or dead from its clumsy attacks, were sonsumed preferably overnight. Not one successful attack of African catfish on healthy prey fish was registered. The SGR and FCR of clarias fed live fish were 0.39%. day-1 and 4.73 respectively. In wels, strong negative selectivity (avoidance was proved for roach (Rutilus rutilus and topmouth gungeon, and lower avoidance for Prussian carp (Carassius auratus gibelio and chub (Leuciscus cephalus. Asp (Aspius aspius were found to be low preferred but high preference was shown for sunbleak, rudd and bitterling (Rhodeus sericeus. Both catfishes preferred smaller prey fish during the 10.day experimental period whilst those which remained non-consumed belonged to the mean or above-mean size categories.

  6. 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.

  7. Detecting directional selection in the presence of recent admixture in African-Americans.

    Science.gov (United States)

    Lohmueller, Kirk E; Bustamante, Carlos D; Clark, Andrew G

    2011-03-01

    We investigate the performance of tests of neutrality in admixed populations using plausible demographic models for African-American history as well as resequencing data from African and African-American populations. The analysis of both simulated and human resequencing data suggests that recent admixture does not result in an excess of false-positive results for neutrality tests based on the frequency spectrum after accounting for the population growth in the parental African population. Furthermore, when simulating positive selection, Tajima's D, Fu and Li's D, and haplotype homozygosity have lower power to detect population-specific selection using individuals sampled from the admixed population than from the nonadmixed population. Fay and Wu's H test, however, has more power to detect selection using individuals from the admixed population than from the nonadmixed population, especially when the selective sweep ended long ago. Our results have implications for interpreting recent genome-wide scans for positive selection in human populations. © 2011 by the Genetics Society of America

  8. 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.

  9. I n vitro activity of three selected South African medicinal plants ...

    African Journals Online (AJOL)

    I n vitro activity of three selected South African medicinal plants against human immunodeficiency virus type 1 reverse transcriptase. ... Ribonuclease H activity was evaluated by measuring the extent of degradation of a radiolabelled RNA in an RNA/DNA hybrid by reverse transcriptase in the presence of test substance.

  10. 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

  11. Perceptions of selected science careers by African American high school males

    Science.gov (United States)

    Ijames, Erika Denise

    Research indicates that internal and external factors such as role models, stereotypes, and pressures placed on African American males by their family and friends influence their perceptions of science careers (Assibey-Mensah, 1997; Hess & Leal, 1997; Jacobowitz, 1983; Maple & Stage, 1991; Thomas, 1989; Ware & Lee, 1988). The purpose of this research was to investigate the perceptions of African American high school males about selected science careers based on apparent internal and external factors. Two questions guided this research: (1) What are high school African American males' perceptions of science careers? (2) What influences high school African American males' perceptions of science careers? This research was based on a pilot study in which African American college males perceived a selection of science careers along racial and gender lines. The follow-up investigation was conducted at Rockriver High School in Acorn County, and the participants were three college-bound African American males. The decision to choose males was based on the concept of occupational niching along gender lines. In biology, niching is defined as the role of a particular species regarding space and reproduction, and its interactions with other factors. During the seven-week period of the students' senior year, they met with the researcher to discuss their perceptions of science careers. An ethnographic approach was used to allow a richer and thicker narrative to occur. Critical theory was used to describe and interpret the voices of the participants from a social perspective. The data collected were analyzed using a constant comparative analysis technique. The participants revealed role models, negative stereotypes, peer pressure, social pressures, and misconceptions as some of the factors that influenced their perceptions of science careers. Results of this research suggest that by dispelling the misconceptions, educators can positively influence the attitudes and perceptions of

  12. Unbiased split variable selection for random survival forests using maximally selected rank statistics.

    Science.gov (United States)

    Wright, Marvin N; Dankowski, Theresa; Ziegler, Andreas

    2017-04-15

    The most popular approach for analyzing survival data is the Cox regression model. The Cox model may, however, be misspecified, and its proportionality assumption may not always be fulfilled. An alternative approach for survival prediction is random forests for survival outcomes. The standard split criterion for random survival forests is the log-rank test statistic, which favors splitting variables with many possible split points. Conditional inference forests avoid this split variable selection bias. However, linear rank statistics are utilized by default in conditional inference forests to select the optimal splitting variable, which cannot detect non-linear effects in the independent variables. An alternative is to use maximally selected rank statistics for the split point selection. As in conditional inference forests, splitting variables are compared on the p-value scale. However, instead of the conditional Monte-Carlo approach used in conditional inference forests, p-value approximations are employed. We describe several p-value approximations and the implementation of the proposed random forest approach. A simulation study demonstrates that unbiased split variable selection is possible. However, there is a trade-off between unbiased split variable selection and runtime. In benchmark studies of prediction performance on simulated and real datasets, the new method performs better than random survival forests if informative dichotomous variables are combined with uninformative variables with more categories and better than conditional inference forests if non-linear covariate effects are included. In a runtime comparison, the method proves to be computationally faster than both alternatives, if a simple p-value approximation is used. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  13. Prey Selection by African Catfish Clarias gariepinus (Burchell, 1822) Larvae Fed Different Feeding Regimes

    OpenAIRE

    Yilmaz, Erdal; Bozkurt, Ahmet; GÖKÇEK, Kaya

    2006-01-01

    Live prey selection by African catfish, Clarias gariepinus, larvae was examined under laboratory conditions. Larvae were offered plankton, plankton + trout starter (TS) and plankton + betaine supplemented trout diet (BTS) for 7 days after exogenous feeding. Five larvae were sampled to determine their gut contents and selectivity index for each treatment 15 min after the feeding. It was observed that dry diets (TS and BTS) improved the growth (P < 0.05), but did not significantly influe...

  14. 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.

  15. Genome-wide Scan of 29,141 African Americans Finds No Evidence of Directional Selection since Admixture

    Science.gov (United States)

    Bhatia, Gaurav; Tandon, Arti; Patterson, Nick; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; Blot, William J.; Bock, Cathryn H.; Caporaso, Neil; Casey, Graham; Deming, Sandra L.; Diver, W. Ryan; Gapstur, Susan M.; Gillanders, Elizabeth M.; Harris, Curtis C.; Henderson, Brian E.; Ingles, Sue A.; Isaacs, William; De Jager, Phillip L.; John, Esther M.; Kittles, Rick A.; Larkin, Emma; McNeill, Lorna H.; Millikan, Robert C.; Murphy, Adam; Neslund-Dudas, Christine; Nyante, Sarah; Press, Michael F.; Rodriguez-Gil, Jorge L.; Rybicki, Benjamin A.; Schwartz, Ann G.; Signorello, Lisa B.; Spitz, Margaret; Strom, Sara S.; Tucker, Margaret A.; Wiencke, John K.; Witte, John S.; Wu, Xifeng; Yamamura, Yuko; Zanetti, Krista A.; Zheng, Wei; Ziegler, Regina G.; Chanock, Stephen J.; Haiman, Christopher A.; Reich, David; Price, Alkes L.

    2014-01-01

    The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection after admixture was reported on the basis of deviations in local ancestry, and selection before admixture was reported on the basis of allele-frequency differences between African Americans and African populations. The local-ancestry deviations reported by the previous study did not replicate in our very large sample, and we show that such deviations were expected purely by chance, given the number of hypotheses tested. We further show that the previous study’s conclusion of selection in African Americans before admixture is also subject to doubt. This is because the FST statistics they used were inflated and because true signals of unusual allele-frequency differences between African Americans and African populations would be best explained by selection that occurred in Africa prior to migration to the Americas. PMID:25242497

  16. Genome-wide scan of 29,141 African Americans finds no evidence of directional selection since admixture.

    Science.gov (United States)

    Bhatia, Gaurav; Tandon, Arti; Patterson, Nick; Aldrich, Melinda C; Ambrosone, Christine B; Amos, Christopher; Bandera, Elisa V; Berndt, Sonja I; Bernstein, Leslie; Blot, William J; Bock, Cathryn H; Caporaso, Neil; Casey, Graham; Deming, Sandra L; Diver, W Ryan; Gapstur, Susan M; Gillanders, Elizabeth M; Harris, Curtis C; Henderson, Brian E; Ingles, Sue A; Isaacs, William; De Jager, Phillip L; John, Esther M; Kittles, Rick A; Larkin, Emma; McNeill, Lorna H; Millikan, Robert C; Murphy, Adam; Neslund-Dudas, Christine; Nyante, Sarah; Press, Michael F; Rodriguez-Gil, Jorge L; Rybicki, Benjamin A; Schwartz, Ann G; Signorello, Lisa B; Spitz, Margaret; Strom, Sara S; Tucker, Margaret A; Wiencke, John K; Witte, John S; Wu, Xifeng; Yamamura, Yuko; Zanetti, Krista A; Zheng, Wei; Ziegler, Regina G; Chanock, Stephen J; Haiman, Christopher A; Reich, David; Price, Alkes L

    2014-10-02

    The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection after admixture was reported on the basis of deviations in local ancestry, and selection before admixture was reported on the basis of allele-frequency differences between African Americans and African populations. The local-ancestry deviations reported by the previous study did not replicate in our very large sample, and we show that such deviations were expected purely by chance, given the number of hypotheses tested. We further show that the previous study's conclusion of selection in African Americans before admixture is also subject to doubt. This is because the FST statistics they used were inflated and because true signals of unusual allele-frequency differences between African Americans and African populations would be best explained by selection that occurred in Africa prior to migration to the Americas. Copyright © 2014 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  17. Cytotoxic activity of selected Nigerian plants | Sowemimo | African ...

    African Journals Online (AJOL)

    Cytotoxic activity of selected Nigerian plants. ... Abstract. Cancer is one of the most prominent human diseases which has stimulated scientific and commercial interest in the discovery of new anticancer agents from natural sources. The current study ... Keywords: Medicinal plants; Cytotoxicity; Cancer; Sapium; Combretum ...

  18. Public debt and growth in selected West African countries ...

    African Journals Online (AJOL)

    Based on an eclectic approach, we examined the public debt – growth nexus in selected SSA countries. Panel regression results indicate that debt/GDP and rates of inflation had negative relationship with the growth in real GDP and its per capita measure for SSA. For the ECOWAS countries, debt/GDP was positively ...

  19. South African medical schools: Current state of selection criteria and ...

    African Journals Online (AJOL)

    Of these, 78% of places are offered to black students, 11% to white, 8% to coloured and 3% to Indian students. No allowance is made for gender or disadvantage. At UP, targets are set for historically disadvantaged students, namely black and coloured, while at SUN male and female students are selected in the same ratio ...

  20. Allelopathic potential of selected rice varieties | Karim | African ...

    African Journals Online (AJOL)

    Journal Home > Vol 11, No 88 (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 should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat ...

  1. A review of genomic selection - Implications for the South African ...

    African Journals Online (AJOL)

    The major advancements in molecular technology over the past decades led to the discovery of DNA-markers, sequencing and genome mapping of farm animal species. New avenues were created for identifying major genes, genetic defects, quantitative trait loci (QTL) and ultimately applying genomic selection (GS) in ...

  2. A review of genomic selection - Implications for the South African ...

    African Journals Online (AJOL)

    2013-03-09

    Mar 9, 2013 ... Daetwyler, H.D., Villanueva, B., Bijma, P. & Woolliams, J.A., 2007. Inbreeding in genome-wide selection. J. Anim. Breed. Genet.124, 369-376. Daetwyler, H.D., Villanueva, B. & Woolliams, J.A., 2008. Accuracy of predicting the genetic risk of disease using a genome-wide approach. PLoS ONE 3, e3395.

  3. African signatures of recent positive selection in human FOXI1

    Directory of Open Access Journals (Sweden)

    Moreno-Estrada Andrés

    2010-09-01

    Full Text Available Abstract Background The human FOXI1 gene codes for a transcription factor involved in the physiology of the inner ear, testis, and kidney. Using three interspecies comparisons, it has been suggested that this may be a gene under human-specific selection. We sought to confirm this finding by using an extended set of orthologous sequences. Additionally, we explored for signals of natural selection within humans by sequencing the gene in 20 Europeans, 20 East Asians and 20 Yorubas and by analysing SNP variation in a 2 Mb region centered on FOXI1 in 39 worldwide human populations from the HGDP-CEPH diversity panel. Results The genome sequences recently available from other primate and non-primate species showed that FOXI1 divergence patterns are compatible with neutral evolution. Sequence-based neutrality tests were not significant in Europeans, East Asians or Yorubas. However, the Long Range Haplotype (LRH test, as well as the iHS and XP-Rsb statistics revealed significantly extended tracks of homozygosity around FOXI1 in Africa, suggesting a recent episode of positive selection acting on this gene. A functionally relevant SNP, as well as several SNPs either on the putatively selected core haplotypes or with significant iHS or XP-Rsb values, displayed allele frequencies strongly correlated with the absolute geographical latitude of the populations sampled. Conclusions We present evidence for recent positive selection in the FOXI1 gene region in Africa. Climate might be related to this recent adaptive event in humans. Of the multiple functions of FOXI1, its role in kidney-mediated water-electrolyte homeostasis is the most obvious candidate for explaining a climate-related adaptation.

  4. Bupropion for Smoking Cessation in African American Light Smokers: A Randomized Controlled Trial

    Science.gov (United States)

    Nollen, Nicole L.; Mayo, Matthew S.; Choi, Won S.; Faseru, Babalola; Benowitz, Neal L.; Tyndale, Rachel F.; Okuyemi, Kolawole S.; Ahluwalia, Jasjit S.

    2012-01-01

    Background Previous research demonstrated the efficacy of sustained release bupropion (bupropion SR) for smoking cessation in whites as well as moderate to heavy (≥10 cigarettes per day [CPD]) African American smokers. We evaluated whether bupropion SR was effective for smoking cessation among African American light smokers (≤10 CPD). Methods A randomized, double-blind placebo-controlled trial was conducted from December 27, 2007, to May 13, 2010. All participants were African American light smokers (≤10 CPD), aged 18 years or older. Participants were randomly assigned to receive 300 mg bupropion SR (150 mg once daily for 3 days and then 150 mg twice daily) (n = 270 participants) or placebo (n = 270 participants) for 7 weeks, and up to six sessions of health education counseling. Serum cotinine was measured at baseline (week 0). The primary outcome was salivary cotinine–verified 7-day point prevalence smoking abstinence at week 26; a cut point of 15 ng/mL differentiated smokers from nonsmokers. Salivary cotinine–verified smoking abstinence at end of medication treatment at week 7 was also examined. Odds ratios (OR) for smoking abstinence and 95% confidence intervals (CIs) were calculated using logistic regression models. All statistical tests were two-sided. Results Participants at baseline visit (week 0) smoked an average of 8.0 CPD and had a mean serum cotinine level of 275.8 ng/mL (SD = 155.8 ng/mL); most used menthol cigarettes (83.7%) and smoked within 30 minutes of waking (72.2%). After imputing those lost to follow-up as smokers, no statistically significant difference in long-term smoking abstinence rates at week 26 was observed between bupropion SR and placebo groups (13.3% vs 10.0%, OR = 1.39, 95% CI = 0.82 to 2.35, P = .23). Cotinine-verified smoking abstinence rate at end of medication week 7 was higher in the bupropion SR vs placebo group (23.7% vs 9.6%, OR = 2.92, 95% CI = 1.78 to 4.77, P Bupropion SR was effective in promoting smoking

  5. 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.

  6. Preventing excessive gestational weight gain among African American women: A randomized clinical trial.

    Science.gov (United States)

    Herring, Sharon J; Cruice, Jane F; Bennett, Gary G; Rose, Marisa Z; Davey, Adam; Foster, Gary D

    2016-01-01

    Evidence is lacking regarding effective weight control treatments in pregnancy for ethnic minority women with obesity. This study evaluated whether a technology-based behavioral intervention could decrease the proportion of African American women with overweight or obesity who exceeded Institute of Medicine (IOM) guidelines for gestational weight gain. We conducted a two-arm pilot randomized clinical trial. Participants were 66 socioeconomically disadvantaged African American pregnant women (12.5 ± 3.7 weeks' gestation; 36% overweight, 64% obesity) recruited from two outpatient obstetric practices at Temple University between 2013 and 2014. We randomized participants to usual care (n = 33) or a behavioral intervention (n = 33) that promoted weight control in pregnancy. The intervention included: (1) empirically supported behavior change goals; (2) interactive self-monitoring text messages; (3) biweekly health coach calls; and (4) skills training and support through Facebook. The intervention reduced the proportion of women who exceeded IOM guidelines compared to usual care (37% vs. 66%, P = 0.033). Intervention participants gained less weight during pregnancy (8.7 vs. 12.3 kg, adjusted mean difference: -3.1 kg, 95% CI: -6.2 to -0.1). No group differences in neonatal or obstetric outcomes were found. The intervention resulted in lower prevalence of excessive gestational weight gain. © 2015 The Obesity Society.

  7. 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).

  8. 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 (Ppsychomotricity a safe and efficacy therapy for pediatric selective mutism.

  9. 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.

  10. The influence of intergroup comparisons on Africans' intelligence test performance in a job selection context.

    Science.gov (United States)

    Klein, Olivier; Pohl, Sabine; Ndagijimana, Chantal

    2007-09-01

    Sub-Saharan Africans living in Belgium (N = 69) completed a culture-free intelligence test in a simulated job selection environment. Prior to testing, the authors instructed participants that Africans' average performance on this test was generally better (positive comparison), worse (negative comparison), or equal to Belgians' performance. In a control condition, no such information was given. Results indicated that, compared with the equal and control conditions, performance was lower when intergroup comparisons were negative. In the former condition, participants were also more likely to endorse external factors that may account for lower performance. The authors interpreted the findings in line with stereotype threat theory (C. M. Steele & J. Aronson, 1995). In the context of job selection, the validity of intelligence tests conducted with members of stigmatized groups may be affected by the salience of social stereotypes and intergroup social comparisons.

  11. African-American Women's Long-term Maintenance of Physical Activity Following a Randomized Controlled Trial.

    Science.gov (United States)

    Wilbur, JoEllen; Miller, Arlene M; Buchholz, Susan W; Fogg, Louis F; Braun, Lynne T; Halloway, Shannon; Schoeny, Michael E

    2017-07-01

    Our purpose was to determine long-term maintenance of physical activity (PA) following the 48-week Women's Lifestyle PA program, targeted/tailored for African-American women. The parent study consisted of a 3-arm randomized clinical trial with 3 assessment points: baseline (pre-intervention); 24 weeks post-baseline (end active intervention); and 48 weeks post-baseline (end maintenance intervention). Present analyses supplement the original results by adding a long-term maintenance assessment that occurred 2 to 4 years post-baseline. Participants were 288 African-American women aged 40 to 65 without major signs/symptoms of pulmonary/cardiovascular disease. The active intervention included 5 group meetings, with 9 personal motivational calls, 9 automated motivational calls, or no calls between meetings. The maintenance intervention included one group meeting and either 2 calls or no calls. PA was assessed with the Community Healthy Activities Model Program for Seniors. Retention was 90%. Over long-term maintenance, there was a decline in PA, but levels remained significantly higher than baseline for moderate/vigorous PA (p maintenance of PA increases resulting from group meetings in an active intervention occur when followed by a maintenance intervention.

  12. 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…

  13. Event selection with a Random Forest in IceCube

    Energy Technology Data Exchange (ETDEWEB)

    Ruhe, Tim [TU, Dortmund (Germany); Collaboration: IceCube-Collaboration

    2011-07-01

    The Random Forest method is a multivariate algorithm that can be used for classification and regression respectively. The Random Forest implemented in the RapidMiner learning environment has been used for training and validation on data and Monte Carlo simulations of the IceCube neutrino telescope. Latest results are presented.

  14. Factors Associated with Discontinuation of Bupropion and Counseling among African American Light Smokers in a Randomized Clinical Trial

    Science.gov (United States)

    Nollen, Nicole L.; Mayo, Matthew S.; Ahluwalia, Jasjit S.; Tyndale, Rachel F.; Benowitz, Neal L.; Faseru, Babalola; Buchanan, Taneisha S.; Cox, Lisa Sanderson

    2013-01-01

    Background African Americans are at risk for inadequate adherence to smoking cessation treatment yet little is known about what leads to treatment discontinuation. Purpose Examine the factors associated with discontinuation of treatment in African American light smokers (≤10 cigarettes per day). Methods Bupropion plasma levels and counseling attendance were measured among 540 African American light smokers in a placebo-controlled randomized trial of bupropion. Results By Week 3, 28.0% of subjects in the bupropion arm had discontinued bupropion and only moderate associations were found between plasma levels and self-reported bupropion use (rs=0.38). By Week 16, 36.9% of all subjects had discontinued counseling. Males had greater odds of discontinuing medication (OR=2.02, 95% CI, 1.10–3.71, p=0.02) and older adults had lower odds of discontinuing counseling (OR=0.96, 95% CI, 0.94–0.97, pBupropion and smoking cessation counseling are underutilized even when provided within the context of a randomized trial. Future research is needed to examine strategies for improving treatment utilization among African American smokers. PMID:23733379

  15. Moving Heaven and Earth: Administrative Search and Selection Processes and the Experience of an African American Woman Senior Administrator

    Science.gov (United States)

    Barnett-Johnson, Kim R.

    2009-01-01

    The purpose of this case/phenomenological study was to examine a collegiate administrative search and selection process and the experience of an African American woman who was selected to the position of chancellor. A case concerning the search process of a regional campus of Ivy Tech Community College of Indiana was identified and chosen.…

  16. Study on MAX-MIN Ant System with Random Selection in Quadratic Assignment Problem

    Science.gov (United States)

    Iimura, Ichiro; Yoshida, Kenji; Ishibashi, Ken; Nakayama, Shigeru

    Ant Colony Optimization (ACO), which is a type of swarm intelligence inspired by ants' foraging behavior, has been studied extensively and its effectiveness has been shown by many researchers. The previous studies have reported that MAX-MIN Ant System (MMAS) is one of effective ACO algorithms. The MMAS maintains the balance of intensification and diversification concerning pheromone by limiting the quantity of pheromone to the range of minimum and maximum values. In this paper, we propose MAX-MIN Ant System with Random Selection (MMASRS) for improving the search performance even further. The MMASRS is a new ACO algorithm that is MMAS into which random selection was newly introduced. The random selection is one of the edgechoosing methods by agents (ants). In our experimental evaluation using ten quadratic assignment problems, we have proved that the proposed MMASRS with the random selection is superior to the conventional MMAS without the random selection in the viewpoint of the search performance.

  17. Design, baseline characteristics, and retention of African American light smokers into a randomized trial involving biological data

    Directory of Open Access Journals (Sweden)

    Okuyemi Kolawole S

    2011-01-01

    Full Text Available Abstract Background African Americans experience significant tobacco-related health disparities despite the fact that over half of African American smokers are light smokers (use ≤10 cigarettes per day. African Americans have been under-represented in smoking cessation research, and few studies have evaluated treatment for light smokers. This paper describes the study design, measures, and baseline characteristics from Kick It at Swope III (KIS-III, the first treatment study of bupropion for African American light smokers. Methods Five hundred forty African American light smokers were randomly assigned to receive bupropion (150mg bid (n = 270 or placebo (n = 270 for 7 weeks. All participants received written materials and health education counseling. Participants responded to survey items and provided blood samples for evaluation of phenotype and genotype of CYP2A6 and CYP2B6 enzymes involved in nicotine and bupropion metabolism. Primary outcome was cotinine-verified 7-day point prevalence smoking abstinence at Week 26 follow-up. Results Of 2,628 individuals screened, 540 were eligible, consented, and randomized to treatment. Participants had a mean age of 46.5 years and 66.1% were women. Participants smoked an average of 8.0 cigarettes per day, had a mean exhaled carbon monoxide of 16.4ppm (range 1-55 and a mean serum cotinine of 275.8ng/ml. The mean Fagerström Test for Nicotine Dependence was 3.2, and 72.2% of participants smoked within 30 minutes of waking. The average number of quit attempts in the past year was 3.7 and 24.2% reported using pharmacotherapy in their most recent quit attempt. Motivation and confidence to quit were high. Conclusion KIS-III is the first study designed to examine both nicotine and bupropion metabolism, evaluating CYP2A6 and CYP2B6 phenotype and genotype in conjunction with psychosocial factors, in the context of treatment of African American light smokers. Of 1629 smokers screened for study participation, only

  18. Carotenoid profiling of the leaves of selected African eggplant accessions subjected to drought stress.

    Science.gov (United States)

    Mibei, Elias K; Ambuko, Jane; Giovannoni, James J; Onyango, Arnold N; Owino, Willis O

    2017-01-01

    African eggplants (Solanum aethiopicum and S. macrocarpon) are among the most economically important and valuable vegetable and fruit crops. They are a major source of biologically active nutritional substances and metabolites which are essential for plant growth, development, stress adaptation and defense. Among these metabolites are the carotenoids which act as accessory pigments for photosynthesis and precursor to plant hormones. Though African eggplants are known to be resistant to various abiotic stresses, the effect of these stresses on secondary metabolites has not been well defined. The objective of this study was to establish the effect of drought stress on carotenoid profiles of nineteen African eggplant accessions selected based on leaf and fruit morphological traits. Stress was achieved by limiting irrigation and maintaining the wilting state of the crops. Fresh leaves were sampled at different maturity stages; before stress, 2 weeks and 4 weeks after stress for carotenoid analysis. The fresh harvested leaf tissues were immediately frozen in liquid nitrogen and ground. Analysis was carried out using a Dionex HPLC machine coupled to Photo Array Detector and Chromeleon software package (Thermo Fisher Scientific Inc, Waltham, Massachusetts, USA). Major carotenoids viz;. Xanthophylls (neoxanthin, violaxanthin, zeaxanthin and lutein) and carotenes (β-carotene and α-carotene), phytofluene, lycopene, phytoene as well as chlorophylls (chlorophyll-b and Chlorophyll-a) were targeted. The carotenoids increased with maturity stage of the crop. Although the stressed crops reported significantly decreased amount of carotenes, chlorophylls, neoxanthin and violaxanthin, the concentration of zeaxanthin increased with stress whereas lutein had no significant change. Chlorophyll-a was significantly high in all the control accessions. Two accessions reported significantly higher contents of carotenoids as compared to the other accessions. The results of this study

  19. Cognitive-Behavioral Therapy to Promote Smoking Cessation among African American Smokers: A Randomized Clinical Trial

    Science.gov (United States)

    Webb, Monica S.; de Ybarra, Denise Rodriguez; Baker, Elizabeth A.; Reis, Isildinha M.; Carey, Michael P.

    2010-01-01

    Objective: The health consequences of tobacco smoking disproportionately affect African Americans, but research on whether efficacious interventions can be generalized to this population is limited. This study examined the efficacy of group-based cognitive-behavioral therapy (CBT) for smoking cessation among African Americans. Method: Participants…

  20. 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.

  1. 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.

  2. AN EXPLORATORY STUDY OF LONG SUPPLY CHAIN COMPETITION: SELECTED CASES IN THE SOUTH AFRICAN AEROSPACE SECTOR

    Directory of Open Access Journals (Sweden)

    L.J. Richardson

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: This article investigates how supply chains, especially long supply chains, compete in the South African aerospace industry. A multiple case study methodology is employed, involving six selected firms. Semi-structured interviews provide the primary source of data. Multiple case analysis identifies similarities in competitive dimension criteria for supplier-firm and customer-firm units in the supply chain. Results indicate that supplier-firm units compete on the basis of speed, dependability, quality, flexibility, and cost. Customer-firm units compete on the basis of speed, quality, and flexibility. The results also identify focus areas for future research into how long supply chains compete in the South African aerospace industry.

    AFRIKAANSE OPSOMMING: Hierdie artikel ondersoek hoe voorsieningskettings, veral uitgerekte kettings, meeding in die Suid-Afrikaanse lugvaartindustrie. ‘n Meervoudige gevallestudie-metodologie is gevolg waartydens ses ondernemings bestudeer is. Semi-gestruktureerde onderhoude was die primêre bron van data. Meervoudige gevalle-analise identifiseer ooreenkomste in die mededingingskriteria vir leweransiers- en kliëntefirmas. Die resultate toon dat leweransiers kompeteer op spoed, betroubaarheid, kwaliteit, aanpasbaarheid en koste. Kliëntefirmas ding mee op grond van spoed, kwaliteit en aanpasbaarheid. Die resultate identifiseer fokusareas vir verdere navorsing op hierdie terrein.

  3. Preventing cognitive decline in older African Americans with mild cognitive impairment: design and methods of a randomized clinical trial.

    Science.gov (United States)

    Rovner, Barry W; Casten, Robin J; Hegel, Mark T; Leiby, Benjamin E

    2012-07-01

    Mild Cognitive Impairment (MCI) affects 25% of older African Americans and predicts progression to Alzheimer's disease. An extensive epidemiologic literature suggests that cognitive, physical, and/or social activities may prevent cognitive decline. We describe the methods of a randomized clinical trial to test the efficacy of Behavior Activation to prevent cognitive decline in older African Americans with the amnestic multiple domain subtype of MCI. Community Health Workers deliver 6 initial in-home treatment sessions over 2-3 months and then 6 subsequent in-home booster sessions using language, materials, and concepts that are culturally relevant to older African Americans during this 24 month clinical trial. We are randomizing 200 subjects who are recruited from churches, senior centers, and medical clinics to Behavior Activation or Supportive Therapy, which controls for attention. The primary outcome is episodic memory as measured by the Hopkins Verbal Learning Test-Revised at baseline and at months 3, 12, 18, and 24. The secondary outcomes are general and domain-specific neuropsychological function, activities of daily living, depression, and quality-of-life. The negative results of recent clinical trials of drug treatments for MCI and Alzheimer's disease suggest that behavioral interventions may provide an alternative treatment approach to preserve cognition in an aging society. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Telephone-Delivered Behavioral Skills Intervention for African American Adults with Type 2 Diabetes: A Randomized Controlled Trial.

    Science.gov (United States)

    Egede, Leonard E; Williams, Joni S; Voronca, Delia C; Gebregziabher, Mulugeta; Lynch, Cheryl P

    2017-07-01

    Diabetes disproportionately affects African Americans and is associated with poorer outcomes. Self-management is important for glycemic control; however, evidence in African Americans is limited. To assess the efficacy of a combined telephone-delivered education and behavioral skills intervention (TBSI) in reducing hemoglobin A1c (HbA1c) levels in African Americans with type 2 diabetes, using a factorial design. This is a four-year randomized clinical trial, using a 2 x 2 factorial design.: Participants: African American adults ≥18 years) with poorly controlled type 2 diabetes (HbA1c ≥9%) were randomly assigned to one of four groups: 1) knowledge only, 2) skills only, 3) combined knowledge and skills (TBSI), or 4) control group. All participants received 12 telephone-delivered 30-min intervention sessions specific to their assigned group. Participants were assessed at baseline and 3, 6, and 12 months. The primary outcome was HbA1c at 12 months post-randomization in the intent-to-treat (ITT) population. Two hundred fifty-five participants were randomly assigned to the four groups. Based on the ITT population after multiple imputation, the analysis of covariance with baseline HbA1c as the covariate showed that HbA1c at 12 months for the intervention groups did not differ significantly from that of the control group (knowledge: 0.49, p = 0.123; skills: 0.23, p = 0.456; combined: 0.48, p = 0.105). Absolute change from baseline at 12 months for all treatment arms was 0.6. Longitudinal mixed effects analysis showed that, on average, there was a significant decline in HbA1c over time for all treatment groups (-0.07, p different from that of the control group (knowledge: 0.06, p = 0.052; skills: 0.02, p = 0.448; combined: 0.05, p = 0.062). Results from per-protocol populations were similar. For African Americans with poorly controlled type 2 diabetes, combined education and skills training did not achieve greater reductions in glycemic

  5. In vivo selection of randomly mutated retroviral genomes

    NARCIS (Netherlands)

    Berkhout, B.; Klaver, B.

    1993-01-01

    Darwinian evolution, that is the outgrowth of the fittest variants in a population, usually applies to living organisms over long periods of time. Recently, in vitro selection/amplification techniques have been developed that allow for the rapid evolution of functionally active nucleic acids from a

  6. Theory-based behavioral intervention increases self-reported physical activity in South African men: a cluster-randomized controlled trial.

    Science.gov (United States)

    Jemmott, John B; Jemmott, Loretta S; Ngwane, Zolani; Zhang, Jingwen; Heeren, G Anita; Icard, Larry D; O'Leary, Ann; Mtose, Xoliswa; Teitelman, Anne; Carty, Craig

    2014-07-01

    To determine whether a health-promotion intervention increases South African men's adherence to physical-activity guidelines. We utilized a cluster-randomized controlled trial design. Eligible clusters, residential neighborhoods near East London, South Africa, were matched in pairs. Within randomly selected pairs, neighborhoods were randomized to theory-based, culturally congruent health-promotion intervention encouraging physical activity or attention-matched HIV/STI risk-reduction control intervention. Men residing in the neighborhoods and reporting coitus in the previous 3 months were eligible. Primary outcome was self-reported individual-level adherence to physical-activity guidelines averaged over 6-month and 12-month post-intervention assessments. Data were collected in 2007-2010. Data collectors, but not facilitators or participants, were blind to group assignment. Primary outcome intention-to-treat analysis included 22 of 22 clusters and 537 of 572 men in the health-promotion intervention and 22 of 22 clusters and 569 of 609 men in the attention-control intervention. Model-estimated probability of meeting physical-activity guidelines was 51.0% in the health-promotion intervention and 44.7% in attention-matched control (OR=1.34; 95% CI, 1.09-1.63), adjusting for baseline prevalence and clustering from 44 neighborhoods. A theory-based culturally congruent intervention increased South African men's self-reported physical activity, a key contributor to deaths from non-communicable diseases in South Africa. ClinicalTrials.gov Identifier: NCT01490359. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. 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...

  8. 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...

  9. The frequency of drugs in randomly selected drivers in Denmark

    DEFF Research Database (Denmark)

    Simonsen, Kirsten Wiese; Steentoft, Anni; Hels, Tove

    Introduction Driving under the influence of alcohol and drugs is a global problem. In Denmark as well as in other countries there is an increasing focus on impaired driving. Little is known about the occurrence of psychoactive drugs in the general traffic. Therefore the European commission...... initiated the DRUID project. This roadside study is the Danish part of the EU-project DRUID (Driving under the Influence of Drugs, Alcohol, and Medicines) and included three representative regions in Denmark. Methods Oral fluid samples (n = 3002) were collected randomly from drivers using a sampling scheme...... stratified by time, season, and road type. The oral fluid samples were screened for 29 illegal and legal psychoactive substances and metabolites as well as ethanol. Results Fourteen (0.5%) drivers were positive for ethanol (alone or in combination with drugs) at concentrations above 0.53 g/l, which...

  10. Sample Selection in Randomized Experiments: A New Method Using Propensity Score Stratified Sampling

    Science.gov (United States)

    Tipton, Elizabeth; Hedges, Larry; Vaden-Kiernan, Michael; Borman, Geoffrey; Sullivan, Kate; Caverly, Sarah

    2014-01-01

    Randomized experiments are often seen as the "gold standard" for causal research. Despite the fact that experiments use random assignment to treatment conditions, units are seldom selected into the experiment using probability sampling. Very little research on experimental design has focused on how to make generalizations to well-defined…

  11. Pseudo cluster randomization dealt with selection bias and contamination in clinical trials

    NARCIS (Netherlands)

    Teerenstra, S.; Melis, R.J.F.; Peer, P.G.M.; Borm, G.F.

    2006-01-01

    BACKGROUND AND OBJECTIVES: When contamination is present, randomization on a patient level leads to dilution of the treatment effect. The usual solution is to randomize on a cluster level, but at the cost of efficiency and more importantly, this may introduce selection bias. Furthermore, it may slow

  12. Proteomic Selection of Immunodiagnostic Antigens for Human African Trypanosomiasis and Generation of a Prototype Lateral Flow Immunodiagnostic Device

    Science.gov (United States)

    Sullivan, Lauren; Wall, Steven J.; Carrington, Mark; Ferguson, Michael A. J.

    2013-01-01

    Background The diagnosis of Human African Trypanosomiasis relies mainly on the Card Agglutination Test for Trypanosomiasis (CATT). While this test is successful, it is acknowledged that there may be room for improvement. Our aim was to develop a prototype lateral flow test based on the detection of antibodies to trypanosome antigens. Methodology/Principal Findings We took a non-biased approach to identify potential immunodiagnostic parasite protein antigens. The IgG fractions from the sera from Trypanosoma brucei gambiense infected and control patients were isolated using protein-G affinity chromatography and then immobilized on Sepharose beads. The IgG-beads were incubated with detergent lysates of trypanosomes and those proteins that bound were identified by mass spectrometry-based proteomic methods. This approach provided a list of twenty-four trypanosome proteins that selectively bound to the infection IgG fraction and that might, therefore, be considered as immunodiagnostic antigens. We selected four antigens from this list (ISG64, ISG65, ISG75 and GRESAG4) and performed protein expression trials in E. coli with twelve constructs. Seven soluble recombinant protein products (three for ISG64, two for ISG65 and one each for ISG75 and GRESAG4) were obtained and assessed for their immunodiagnostic potential by ELISA using individual and/or pooled patient sera. The ISG65 and ISG64 construct ELISAs performed well with respect to detecting T. b. gambiense infections, though less well for detecting T. b. rhodesiense infections, and the best performing ISG65 construct was used to develop a prototype lateral flow diagnostic device. Conclusions/Significance Using a panel of eighty randomized T. b. gambiense infection and control sera, the prototype showed reasonable sensitivity (88%) and specificity (93%) using visual readout in detecting T. b. gambiense infections. These results provide encouragement to further develop and optimize the lateral flow device for clinical

  13. Proteomic selection of immunodiagnostic antigens for human African trypanosomiasis and generation of a prototype lateral flow immunodiagnostic device.

    Directory of Open Access Journals (Sweden)

    Lauren Sullivan

    Full Text Available The diagnosis of Human African Trypanosomiasis relies mainly on the Card Agglutination Test for Trypanosomiasis (CATT. While this test is successful, it is acknowledged that there may be room for improvement. Our aim was to develop a prototype lateral flow test based on the detection of antibodies to trypanosome antigens.We took a non-biased approach to identify potential immunodiagnostic parasite protein antigens. The IgG fractions from the sera from Trypanosoma brucei gambiense infected and control patients were isolated using protein-G affinity chromatography and then immobilized on Sepharose beads. The IgG-beads were incubated with detergent lysates of trypanosomes and those proteins that bound were identified by mass spectrometry-based proteomic methods. This approach provided a list of twenty-four trypanosome proteins that selectively bound to the infection IgG fraction and that might, therefore, be considered as immunodiagnostic antigens. We selected four antigens from this list (ISG64, ISG65, ISG75 and GRESAG4 and performed protein expression trials in E. coli with twelve constructs. Seven soluble recombinant protein products (three for ISG64, two for ISG65 and one each for ISG75 and GRESAG4 were obtained and assessed for their immunodiagnostic potential by ELISA using individual and/or pooled patient sera. The ISG65 and ISG64 construct ELISAs performed well with respect to detecting T. b. gambiense infections, though less well for detecting T. b. rhodesiense infections, and the best performing ISG65 construct was used to develop a prototype lateral flow diagnostic device.Using a panel of eighty randomized T. b. gambiense infection and control sera, the prototype showed reasonable sensitivity (88% and specificity (93% using visual readout in detecting T. b. gambiense infections. These results provide encouragement to further develop and optimize the lateral flow device for clinical use.

  14. Nonlinearities in real exchange rate determination: Do African exchange rates follow a random walk?

    OpenAIRE

    2009-01-01

    Abstract In this paper we aim at modelling the long run behaviour of the Real Effective Exchange Rates (REER) for a pool of African countries. Not much attention has been paid to this group of countries, in particular, to the existence of nonlinearities in the long run path of such a variable. Controlling for two sources of nonlinearites, i.e. asymmetric adjustment to equilibrium and nonlinear deterministic trends allows us to gain some insight about the behaviour of the African R...

  15. Selection of Postgraduate Students in a South African Management Programme: How Effective Is the General Reasoning Test?

    Science.gov (United States)

    Abrahams, Fatima; Friedrich, Christian; Tredoux, Nanette

    2012-01-01

    South African higher education institutions are experiencing challenges regarding access, redress and the successful completion of programmes in an environment where there are still imbalances in the schooling system. Tools are needed that will assist with the process of selecting students. The aim of this study is to determine whether a test…

  16. Acceptance sampling using judgmental and randomly selected samples

    Energy Technology Data Exchange (ETDEWEB)

    Sego, Landon H.; Shulman, Stanley A.; Anderson, Kevin K.; Wilson, John E.; Pulsipher, Brent A.; Sieber, W. Karl

    2010-09-01

    We present a Bayesian model for acceptance sampling where the population consists of two groups, each with different levels of risk of containing unacceptable items. Expert opinion, or judgment, may be required to distinguish between the high and low-risk groups. Hence, high-risk items are likely to be identifed (and sampled) using expert judgment, while the remaining low-risk items are sampled randomly. We focus on the situation where all observed samples must be acceptable. Consequently, the objective of the statistical inference is to quantify the probability that a large percentage of the unsampled items in the population are also acceptable. We demonstrate that traditional (frequentist) acceptance sampling and simpler Bayesian formulations of the problem are essentially special cases of the proposed model. We explore the properties of the model in detail, and discuss the conditions necessary to ensure that required samples sizes are non-decreasing function of the population size. The method is applicable to a variety of acceptance sampling problems, and, in particular, to environmental sampling where the objective is to demonstrate the safety of reoccupying a remediated facility that has been contaminated with a lethal agent.

  17. ENTERPRISE RESOURCE PLANNING SOLUTION SELECTION CRITERIA IN MEDIUMSIZED SOUTH AFRICAN COMPANIES

    Directory of Open Access Journals (Sweden)

    M. Malie

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The purpose of this study is to identify the factors that medium-sized South African companies consider important in the acquisition of an Enterprise Resource Planning (ERP solution. Through an extensive literature review, fourteen ERP selection criteria were identified. Using these fourteen criteria, a questionnaire was developed to test and rate these criteria on a 10-point scale. Results from the survey show that manufacturing and non-manufacturing companies rate reliability, compatibility, service, and support as the most important criteria when selecting an ERP solution.

    AFRIKAANSE OPSOMMING: Die doel van hierdie studie is om die faktore te identifiseer wat deur mediumgrootte Suid-Afrikaanse firmas gebruik kan word in die aankoop van hulpbronbeplanningstelsels. Deur ’n uitgebreide literatuurstudie is veertien kriteria geïdentifiseer wat gebruik kan word as ’n meganisme om die aankoop van die stelsel te evalueer. Uit hierdie kriteria is ’n vraelys ontwerp wat die kriteria toets en evalueer op ’n tien-punt skaal. Uit die ondersoekresultate is gevind dat vervaardiging- en nie-vervaardigingsondernemings betroubaarheid, versoenbaarheid, diens, en ondersteuning beskou as die belangrikste kriteria wat gebruik kan word in die keuse van ’n hulpbronbeplanningstelsel.

  18. 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.

  19. RANDOM FORESTS-BASED FEATURE SELECTION FOR LAND-USE CLASSIFICATION USING LIDAR DATA AND ORTHOIMAGERY

    Directory of Open Access Journals (Sweden)

    H. Guan

    2012-07-01

    Full Text Available The development of lidar system, especially incorporated with high-resolution camera components, has shown great potential for urban classification. However, how to automatically select the best features for land-use classification is challenging. Random Forests, a newly developed machine learning algorithm, is receiving considerable attention in the field of image classification and pattern recognition. Especially, it can provide the measure of variable importance. Thus, in this study the performance of the Random Forests-based feature selection for urban areas was explored. First, we extract features from lidar data, including height-based, intensity-based GLCM measures; other spectral features can be obtained from imagery, such as Red, Blue and Green three bands, and GLCM-based measures. Finally, Random Forests is used to automatically select the optimal and uncorrelated features for landuse classification. 0.5-meter resolution lidar data and aerial imagery are used to assess the feature selection performance of Random Forests in the study area located in Mannheim, Germany. The results clearly demonstrate that the use of Random Forests-based feature selection can improve the classification performance by the selected features.

  20. A cluster randomized controlled trial to increase breast cancer screening among African American women: the black cosmetologists promoting health program.

    Science.gov (United States)

    Sadler, Georgia Robins; Ko, Celine M; Wu, Phillis; Alisangco, Jennifer; Castañeda, Sheila F; Kelly, Colleen

    2011-08-01

    African American women have disproportionately higher rates of breast cancer mortality than all other ethnic groups, thus highlighting the importance of promoting early detection. African American women (N = 984) from San Diego, California, participated in a randomized controlled trial testing the efficacy of breast cancer education sessions offered in beauty salons. Cosmetologists received ongoing support, training, and additional culturally aligned educational materials to help them engage their clients in dialogues about the importance of breast cancer early detection. Posters and literature about breast cancer early detection were displayed throughout the salons and cosmetologists used synthetic breast models to show their clients how breast cancer lumps might feel. Participants in the control group received a comparable diabetes education program. Baseline and 6-month follow-up surveys were administered to evaluate changes in women's breast cancer knowledge, attitudes, and screening behaviors. This intervention was well received by the participants and their cosmetologists and did not interfere with or prolong the client's salon visit. Women in the intervention group reported significantly higher rates of mammography compared to women in the control group. Training a single educator proved sufficient to permeate the entire salon with the health message, and salon clients agreed that cosmetologists could become effective health educators. Cosmetologists are in an ideal position to increase African American women's breast cancer knowledge and adherence to breast cancer screening guidelines.

  1. 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

  2. Breathing retraining for African-American adolescents with asthma: a pilot study of a school-based randomized controlled trial.

    Science.gov (United States)

    Bignall, Whitney Janee Raglin; Luberto, Christina Marie; Cornette, Adrianne Falkenberg; Haj-Hamed, Monzer; Cotton, Sian

    2015-01-01

    Asthma affects approximately seven million children/adolescents in the USA, with African-American children disproportionately affected. Breathing retraining techniques have been shown to improve asthma outcomes in adults, though research in youth is limited. The purpose of this pilot study was to test the feasibility and preliminary efficacy of a school-based randomized controlled trial of breathing retraining for asthma outcomes and anxiety symptoms in a sample of urban, African-American adolescents. Adolescents were randomized into either the intervention group (20-min breathing retraining plus education) or control group (20-min standard education). Participants completed two study visits, one month apart. Asthma control, asthma quality of life and lung functioning (FEV1 and peak flow) were the primary outcomes, and state anxiety (pre-post the intervention) and trait anxiety (over the one-month period) were the secondary outcomes. Thirty-three African-American adolescents participated in the study, with a 90% retention rate between visit 1 and visit 2. Asthma control and asthma quality of life, significantly improved over time (p ≤ 0.01) with no differences between intervention and control groups. State anxiety significantly decreased (p ≤ 0.01) immediately post intervention at both time points with no differences between groups. There were no significant differences found in lung functioning or trait anxiety over the one-month time period. These preliminary results suggest that breathing retraining is a feasible, acceptable and potentially efficacious intervention (although no significant differences between groups were found) for improving asthma symptoms in urban adolescents with asthma in a school-based setting.

  3. Estrogen alone and health outcomes in black women by African ancestry: a secondary analyses of a randomized controlled trial.

    Science.gov (United States)

    Chlebowski, Rowan T; Barrington, Wendy; Aragaki, Aaron K; Manson, JoAnn E; Sarto, Gloria; OʼSullivan, Mary J; Wu, Daniel; Cauley, Jane A; Qi, Lihong; Wallace, Robert L; Prentice, Ross L

    2017-02-01

    In postmenopausal black women in the Women's Health Initiative randomized trial, estrogen alone reduced breast cancers but its comprehensive influence on health outcomes in black women is unknown. Therefore, we examined this issue in the Women's Health Initiative overall and by African ancestry. A total of 1,616 black women with prior hysterectomy, including 1,061 with percent African ancestry determination, at 40 US centers were randomly assigned to conjugated equine estrogen (0.625 mg/d) or placebo for 7.2 years' (median) intervention with 13 years' cumulative follow-up. Coronary heart disease (CHD) and breast cancer were primary efficacy and safety outcomes, respectively. A global index also included stroke, colorectal cancer, hip fracture, pulmonary embolism, and death. Black women in the estrogen-alone group compared with black women in the placebo group had fewer breast cancers (17 vs 40, hazard ratio [HR] 0.47, 95% CI 0.26-0.82). In women with more than 80% African ancestry, breast cancer HR was lower (0.32, 95% CI 0.12-0.86, trend P = 0.04 for ancestry effect). Most other outcomes including CHD, stroke, hip fracture, and the global index were null with estrogen use in black women; a global index effect was more favorable in younger black women (HR 0.65, 95% CI 0.43-0.98). In black postmenopausal women with prior hysterectomy, estrogen alone significantly reduced breast cancer incidence with no adverse influence on CHD, venous thromboembolism, or all-cause mortality. Favorable estrogen-alone global index effects in younger black women warrant further study.

  4. Genomic Comparison of Indigenous African and Northern European Chickens Reveals Putative Mechanisms of Stress Tolerance Related to Environmental Selection Pressure.

    Science.gov (United States)

    Fleming, Damarius S; Weigend, Steffen; Simianer, Henner; Weigend, Annett; Rothschild, Max; Schmidt, Carl; Ashwell, Chris; Persia, Mike; Reecy, James; Lamont, Susan J

    2017-05-05

    Global climate change is increasing the magnitude of environmental stressors, such as temperature, pathogens, and drought, that limit the survivability and sustainability of livestock production. Poultry production and its expansion is dependent upon robust animals that are able to cope with stressors in multiple environments. Understanding the genetic strategies that indigenous, noncommercial breeds have evolved to survive in their environment could help to elucidate molecular mechanisms underlying biological traits of environmental adaptation. We examined poultry from diverse breeds and climates of Africa and Northern Europe for selection signatures that have allowed them to adapt to their indigenous environments. Selection signatures were studied using a combination of population genomic methods that employed FST , integrated haplotype score (iHS), and runs of homozygosity (ROH) procedures. All the analyses indicated differences in environment as a driver of selective pressure in both groups of populations. The analyses revealed unique differences in the genomic regions under selection pressure from the environment for each population. The African chickens showed stronger selection toward stress signaling and angiogenesis, while the Northern European chickens showed more selection pressure toward processes related to energy homeostasis. The results suggest that chromosomes 2 and 27 are the most diverged between populations and the most selected upon within the African (chromosome 27) and Northern European (chromosome 2) birds. Examination of the divergent populations has provided new insight into genes under possible selection related to tolerance of a population's indigenous environment that may be baselines for examining the genomic contribution to tolerance adaptions. Copyright © 2017 Fleming et al.

  5. Genomic Comparison of Indigenous African and Northern European Chickens Reveals Putative Mechanisms of Stress Tolerance Related to Environmental Selection Pressure

    Directory of Open Access Journals (Sweden)

    Damarius S. Fleming

    2017-05-01

    Full Text Available Global climate change is increasing the magnitude of environmental stressors, such as temperature, pathogens, and drought, that limit the survivability and sustainability of livestock production. Poultry production and its expansion is dependent upon robust animals that are able to cope with stressors in multiple environments. Understanding the genetic strategies that indigenous, noncommercial breeds have evolved to survive in their environment could help to elucidate molecular mechanisms underlying biological traits of environmental adaptation. We examined poultry from diverse breeds and climates of Africa and Northern Europe for selection signatures that have allowed them to adapt to their indigenous environments. Selection signatures were studied using a combination of population genomic methods that employed FST, integrated haplotype score (iHS, and runs of homozygosity (ROH procedures. All the analyses indicated differences in environment as a driver of selective pressure in both groups of populations. The analyses revealed unique differences in the genomic regions under selection pressure from the environment for each population. The African chickens showed stronger selection toward stress signaling and angiogenesis, while the Northern European chickens showed more selection pressure toward processes related to energy homeostasis. The results suggest that chromosomes 2 and 27 are the most diverged between populations and the most selected upon within the African (chromosome 27 and Northern European (chromosome 2 birds. Examination of the divergent populations has provided new insight into genes under possible selection related to tolerance of a population’s indigenous environment that may be baselines for examining the genomic contribution to tolerance adaptions.

  6. Metabolomic analyses to evaluate the effect of drought stress on selected African Eggplant accessions.

    Science.gov (United States)

    Mibei, Elias K; Owino, Willis O; Ambuko, Jane; Giovannoni, James J; Onyango, Arnold N

    2018-01-01

    Drought stress is one of the main abiotic stresses that affect crops. It leads to biochemical changes that can have adverse effects on plant growth, development and productivity. African eggplants are important vegetable and fruit crops reported to adapt and thrive well under drought stress. The diversified metabolites arising due to stress have not been well defined. A gas chromatographic-mass spectrometric metabolomic approach was applied to characterize the effect of drought stress on metabolites at different stages of growth. Nineteen accessions were selected for analysis and drought was imposed by withholding water until soil moisture reached 60% field capacity. Fresh leaf tissues were sampled before stress, 2 and 4 weeks after stress and metabolite profiling done. Significant changes in metabolite content were observed, and potentially important metabolites with respect to stress responses were characterized. Proline, glutamate, sucrose, fructose and tricarboxylic acid cycle metabolites were shown to be positively correlated with stress. Principal component analysis showed a clear discrimination between the different accessions, growth stages and stress/control conditions. The results illustrate that drought stress has a significant impact on the concentrations of some metabolites, such as amino acids, sugars and organic acids, which may contribute to drought stress effects and tolerance. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  7. 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.

  8. Genome-wide identification of signatures of positive selection in African admixed zebu cattle

    Science.gov (United States)

    The introduction of humped zebu to the African continent has led to genetic introgression with the local African humpless taurine. A mosaic of zebu x taurine cattle populations adapted to the local environments (e.g., semi-dry desert, humid and sub-humid forested areas) has arisen as a result of thi...

  9. The Journey of the African as Missionary: The Journal and Selected ...

    African Journals Online (AJOL)

    The African Renaissance has been one of the post-apartheid South African state's most resonant political ideas, and was so particularly during the presidency of Thabo Mbeki. It is predicated on the need to go back to the past and recover what was lost, muted or distorted under colonial rule. Such an archaeological exercise ...

  10. SNP selection and classification of genome-wide SNP data using stratified sampling random forests.

    Science.gov (United States)

    Wu, Qingyao; Ye, Yunming; Liu, Yang; Ng, Michael K

    2012-09-01

    For high dimensional genome-wide association (GWA) case-control data of complex disease, there are usually a large portion of single-nucleotide polymorphisms (SNPs) that are irrelevant with the disease. A simple random sampling method in random forest using default mtry parameter to choose feature subspace, will select too many subspaces without informative SNPs. Exhaustive searching an optimal mtry is often required in order to include useful and relevant SNPs and get rid of vast of non-informative SNPs. However, it is too time-consuming and not favorable in GWA for high-dimensional data. The main aim of this paper is to propose a stratified sampling method for feature subspace selection to generate decision trees in a random forest for GWA high-dimensional data. Our idea is to design an equal-width discretization scheme for informativeness to divide SNPs into multiple groups. In feature subspace selection, we randomly select the same number of SNPs from each group and combine them to form a subspace to generate a decision tree. The advantage of this stratified sampling procedure can make sure each subspace contains enough useful SNPs, but can avoid a very high computational cost of exhaustive search of an optimal mtry, and maintain the randomness of a random forest. We employ 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) to demonstrate that the proposed stratified sampling method is effective, and it can generate better random forest with higher accuracy and lower error bound than those by Breiman's random forest generation method. For Parkinson data, we also show some interesting genes identified by the method, which may be associated with neurological disorders for further biological investigations.

  11. Composite Selection Signals for Complex Traits Exemplified Through Bovine Stature Using Multibreed Cohorts of European and African Bos taurus

    Science.gov (United States)

    Randhawa, Imtiaz A. S.; Khatkar, Mehar S.; Thomson, Peter C.; Raadsma, Herman W.

    2015-01-01

    Understanding the evolution and molecular architecture of complex traits is important in domestic animals. Due to phenotypic selection, genomic regions develop unique patterns of genetic diversity called signatures of selection, which are challenging to detect, especially for complex polygenic traits. In this study, we applied the composite selection signals (CSS) method to investigate evidence of positive selection in a complex polygenic trait by examining stature in phenotypically diverse cattle comprising 47 European and 8 African Bos taurus breeds, utilizing a panel of 38,033 SNPs genotyped on 1106 animals. CSS were computed for phenotypic contrasts between multibreed cohorts of cattle by classifying the breeds according to their documented wither height to detect the candidate regions under selection. Using the CSS method, clusters of signatures of selection were detected at 26 regions (9 in European and 17 in African cohorts) on 13 bovine autosomes. Using comparative mapping information on human height, 30 candidate genes mapped at 12 selection regions (on 8 autosomes) could be linked to bovine stature diversity. Of these 12 candidate gene regions, three contained known genes (i.e., NCAPG-LCORL, FBP2-PTCH1, and PLAG1-CHCHD7) related to bovine stature, and nine were not previously described in cattle (five in European and four in African cohorts). Overall, this study demonstrates the utility of CSS coupled with strategies of combining multibreed datasets in the identification and discovery of genomic regions underlying complex traits. Characterization of multiple signatures of selection and their underlying candidate genes will elucidate the polygenic nature of stature across cattle breeds. PMID:25931611

  12. An efficient method of wavelength interval selection based on random frog for multivariate spectral calibration

    Science.gov (United States)

    Yun, Yong-Huan; Li, Hong-Dong; Wood, Leslie R. E.; Fan, Wei; Wang, Jia-Jun; Cao, Dong-Sheng; Xu, Qing-Song; Liang, Yi-Zeng

    2013-07-01

    Wavelength selection is a critical step for producing better prediction performance when applied to spectral data. Considering the fact that the vibrational and rotational spectra have continuous features of spectral bands, we propose a novel method of wavelength interval selection based on random frog, called interval random frog (iRF). To obtain all the possible continuous intervals, spectra are first divided into intervals by moving window of a fix width over the whole spectra. These overlapping intervals are ranked applying random frog coupled with PLS and the optimal ones are chosen. This method has been applied to two near-infrared spectral datasets displaying higher efficiency in wavelength interval selection than others. The source code of iRF can be freely downloaded for academy research at the website: http://code.google.com/p/multivariate-calibration/downloads/list.

  13. Delay line length selection in generating fast random numbers with a chaotic laser.

    Science.gov (United States)

    Zhang, Jianzhong; Wang, Yuncai; Xue, Lugang; Hou, Jiayin; Zhang, Beibei; Wang, Anbang; Zhang, Mingjiang

    2012-04-10

    The chaotic light signals generated by an external cavity semiconductor laser have been experimentally demonstrated to extract fast random numbers. However, the photon round-trip time in the external cavity can cause the occurrence of the periodicity in random sequences. To overcome it, the exclusive-or operation on corresponding random bits in samples of the chaotic signal and its time-delay signal from a chaotic laser is required. In this scheme, the proper selection of delay length is a key issue. By doing a large number of experiments and theoretically analyzing the interplay between the Runs test and the threshold value of the autocorrelation function, we find when the corresponding delay time of autocorrelation trace with the correlation coefficient of less than 0.007 is considered as the delay time between the chaotic signal and its time-delay signal, streams of random numbers can be generated with verified randomness.

  14. The contribution of attenuated selection in utero to small-for-gestational-age (SGA) among term African American male infants.

    Science.gov (United States)

    Goodman, Julia M; Karasek, Deborah; Anderson, Elizabeth; Catalano, Ralph A

    2013-07-01

    Natural selection conserves mechanisms allowing women to spontaneously abort gestations least likely to yield fit offspring. Small gestational size has been proposed as an indicator of fitness observable by maternal biology. Previous research suggests that exposure to ambient stress in utero results in more "culling" of small fetuses and therefore lower rates of small-for-gestational-age (SGA). However, African American women persistently have higher rates of SGA than non-Hispanic white women, despite experiencing more ambient stress. This paper tests whether attenuation of the stress response among highly stressed African American women, as suggested by the weathering hypothesis, may help to explain this apparent inconsistency. We apply time-series modeling to over 2 million African American and non-Hispanic white male term births in California over the period of January 1989 through December 2010. We test for the parabolic (i.e., "U" shaped) relationship, implied by an attenuated stress response, between unusually strong labor market contraction and the rate of SGA among African American term male infants, and a linear relationship among non-Hispanic whites. We find the hypothesized parabolic relationship among term male African American infants. As expected, we find a linear relationship between unexpected layoffs and the rate of SGA among term male non-Hispanic whites. These results are robust to sensitivity analyses. These results may help to explain the high rates of SGA among term male African American infants, despite greater maternal exposure to ambient stress during pregnancy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Pain coping skills training for African Americans with osteoarthritis (STAART): study protocol of a randomized controlled trial.

    Science.gov (United States)

    Schrubbe, Leah A; Ravyts, Scott G; Benas, Bernadette C; Campbell, Lisa C; Cené, Crystal W; Coffman, Cynthia J; Gunn, Alexander H; Keefe, Francis J; Nagle, Caroline T; Oddone, Eugene Z; Somers, Tamara J; Stanwyck, Catherine L; Taylor, Shannon S; Allen, Kelli D

    2016-08-23

    African Americans bear a disproportionate burden of osteoarthritis (OA), with higher prevalence rates, more severe pain, and more functional limitations. One key barrier to addressing these disparities has been limited engagement of African Americans in the development and evaluation of behavioral interventions for management of OA. Pain Coping Skills Training (CST) is a cognitive-behavioral intervention with shown efficacy to improve OA-related pain and other outcomes. Emerging data indicate pain CST may be a promising intervention for reducing racial disparities in OA symptom severity. However, there are important gaps in this research, including incorporation of stakeholder perspectives (e.g. cultural appropriateness, strategies for implementation into clinical practice) and testing pain CST specifically among African Americans with OA. This study will evaluate the effectiveness of a culturally enhanced pain CST program among African Americans with OA. This is a randomized controlled trial among 248 participants with symptomatic hip or knee OA, with equal allocation to a pain CST group and a wait list (WL) control group. The pain CST program incorporated feedback from patients and other stakeholders and involves 11 weekly telephone-based sessions. Outcomes are assessed at baseline, 12 weeks (primary time point), and 36 weeks (to assess maintenance of treatment effects). The primary outcome is the Western Ontario and McMaster Universities Osteoarthritis Index, and secondary outcomes include self-efficacy, pain coping, pain interference, quality of life, depressive symptoms, and global assessment of change. Linear mixed models will be used to compare the pain CST group to the WL control group and explore whether participant characteristics are associated with differential improvement in the pain CST program. This research is in compliance with the Helsinki Declaration and was approved by the Institutional Review Boards of the University of North Carolina at

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

    OpenAIRE

    Olga L. Kupika; Godwell Nhamo

    2016-01-01

    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 ...

  17. Two-year Randomized Clinical Trial Of Self-etching Adhesives And Selective Enamel Etching

    OpenAIRE

    Pena, MR; Rodrigues CE; JA; Ely; Giannini, C.; Reis, M; AF

    2016-01-01

    Objective: 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. Methods: 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...

  18. The providing resources to enhance African American patients' readiness to make decisions about kidney disease (PREPARED) study: protocol of a randomized controlled trial.

    Science.gov (United States)

    Ephraim, Patti L; Powe, Neil R; Rabb, Hamid; Ameling, Jessica; Auguste, Priscilla; Lewis-Boyer, LaPricia; Greer, Raquel C; Crews, Deidra C; Purnell, Tanjala S; Jaar, Bernard G; DePasquale, Nicole; Boulware, L Ebony

    2012-10-12

    Living related kidney transplantation (LRT) is underutilized, particularly among African Americans. The effectiveness of informational and financial interventions to enhance informed decision-making among African Americans with end stage renal disease (ESRD) and improve rates of LRT is unknown. We report the protocol of the Providing Resources to Enhance African American Patients' Readiness to Make Decisions about Kidney Disease (PREPARED) Study, a two-phase study utilizing qualitative and quantitative research methods to design and test the effectiveness of informational (focused on shared decision-making) and financial interventions to overcome barriers to pursuit of LRT among African American patients and their families. Study Phase I involved the evidence-based development of informational materials as well as a financial intervention to enhance African American patients' and families' proficiency in shared decision-making regarding LRT. In Study Phase 2, we are currently conducting a randomized controlled trial in which patients with new-onset ESRD receive 1) usual dialysis care by their nephrologists, 2) the informational intervention (educational video and handbook), or 3) the informational intervention in addition to the option of participating in a live kidney donor financial assistance program. The primary outcome of the randomized controlled trial will include patients' self-reported rates of consideration of LRT (including family discussions of LRT, patient-physician discussions of LRT, and identification of a LRT donor). Results from the PREPARED study will provide needed evidence on ways to enhance the decision to pursue LRT among African American patients with ESRD.

  19. 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

    2016-03-01

    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

  20. An entertainment-education colorectal cancer screening decision aid for African American patients: A randomized controlled trial.

    Science.gov (United States)

    Hoffman, Aubri S; Lowenstein, Lisa M; Kamath, Geetanjali R; Housten, Ashley J; Leal, Viola B; Linder, Suzanne K; Jibaja-Weiss, Maria L; Raju, Gottumukkala S; Volk, Robert J

    2017-04-15

    Colorectal cancer screening rates for African American patients remain suboptimal. Patient decision aids designed with an entertainment-education approach have been shown to improve saliency and foster informed decision making. The purpose of this study was to assess whether an entertainment-education decision aid tailored for African American patients improved patients' decision making, attitudes, intentions, or colorectal cancer screening behavior. Eighty-nine participants were randomized to view 1) a patient decision aid video containing culturally tailored information about colorectal cancer screening options and theory-based support in decision making presented in an entertainment-education format or 2) an attention control video about hypertension that contained similarly detailed information. Participants met with their clinician and then completed follow-up questionnaires assessing their knowledge, decisional conflict, self-advocacy, attitudes, perceived social norms, and intentions. At 3 months, completion of screening was assessed by chart review. Viewing the culturally tailored decision aid significantly increased African American patients' knowledge of colorectal cancer screening recommendations and options. It also significantly reduced their decisional conflict and improved their self-advocacy. No significant differences were observed in participants' attitudes, norms, or intentions. At three months, 23% of all patients had completed a colonoscopy. Designing targeted, engaging patient decision aids for groups that receive suboptimal screening holds promise for improving patient decision making and self-advocacy. Additional research is warranted to investigate the effectiveness of such aids in clinical practices with suboptimal screening rates and on downstream behaviors (such as repeat testing). Cancer 2017;123:1401-1408. © 2016 American Cancer Society. © 2016 American Cancer Society.

  1. 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.

  2. The value and role of non-invasive prenatal testing in a select South African population.

    Science.gov (United States)

    Mnyani, C N; Nicolaou, E; Bister, S

    2016-09-09

    Concerns have been raised about the injudicious use of non-invasive prenatal testing (NIPT) using cell-free DNA (cfDNA), which often leads to inaccuracies in interpretation of the role and value of cfDNA in prenatal screening.  To determine the value and role of NIPT in a select South African (SA) population.  A retrospective review of patients who elected to have NIPT between 1 October 2013 and 30 June 2015 at the Morningside Mediclinic Maternal and Fetal Medicine Centre in Johannesburg, SA. Patients had NIPT after either combined first-trimester screening (CFTS) or a second-trimester ultrasound scan. Data were collected on details of the first- and/or second-trimester screening, results of the NIPT, invasive tests done, decisions made in the event of abnormal results, and pregnancy outcomes.  Overall, 3 473 first- and second-trimester fetal assessments were done at the centre during the study period, and 2.3% of patients (n=82) elected to have NIPT. The majority of these individuals elected to have NIPT on the basis of positive findings on CFTS, or markers of aneuploidy detected on a second-trimester ultrasound scan. Of the tests done, 97.6% produced results. Of those with no results, one did not meet quality metrics and the other had a low fetal fraction of cfDNA. There were two abnormal NIPT results, one indicating a high risk of trisomy 13 and the other a triploidy. Patients who screened negative elected not to have an invasive test.  The value of NIPT in this study was that it made it possible to avoid a number of invasive tests. NIPT had a role in contingency screening.

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

    Science.gov (United States)

    Lindsay, Grace W; Rigotti, Mattia; Warden, Melissa R; Miller, Earl K; Fusi, Stefano

    2017-11-08

    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 ("mixed

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

    DEFF Research Database (Denmark)

    Heide, Janus; Zhang, Qi; Fitzek, Frank

    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...

  5. 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…

  6. 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

  7. 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

    2011-09-01

    To test the long-term effects of a mass media intervention that used culturally and developmentally appropriate messages to enhance human immunodeficiency virus (HIV)-preventive beliefs and behavior of high-risk African American adolescents. Television and radio messages were delivered for more than 3 years in two cities (Syracuse, NY; and Macon, GA) that were randomly selected within each of the two regionally matched city pairs, with the other cities (Providence, RI; and Columbia, SC) serving as controls. African American adolescents, aged 14-17 years (N = 1,710), 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 postrecruitment 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 the three sexually transmitted infections at recruitment or at 6-and 12-month follow-up were retained for analysis (N = 1,346). The media intervention reached virtually all 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 (aged 16-17 years) exposed to the media program showed a less risky age trajectory of unprotected sex than those in the nonmedia cities. Culturally tailored mass media messages that are 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. Copyright © 2011 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  8. 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.

  9. 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.

  10. Classification of epileptic EEG signals based on simple random sampling and sequential feature selection.

    Science.gov (United States)

    Ghayab, Hadi Ratham Al; Li, Yan; Abdulla, Shahab; Diykh, Mohammed; Wan, Xiangkui

    2016-06-01

    Electroencephalogram (EEG) signals are used broadly in the medical fields. The main applications of EEG signals are the diagnosis and treatment of diseases such as epilepsy, Alzheimer, sleep problems and so on. This paper presents a new method which extracts and selects features from multi-channel EEG signals. This research focuses on three main points. Firstly, simple random sampling (SRS) technique is used to extract features from the time domain of EEG signals. Secondly, the sequential feature selection (SFS) algorithm is applied to select the key features and to reduce the dimensionality of the data. Finally, the selected features are forwarded to a least square support vector machine (LS_SVM) classifier to classify the EEG signals. The LS_SVM classifier classified the features which are extracted and selected from the SRS and the SFS. The experimental results show that the method achieves 99.90, 99.80 and 100 % for classification accuracy, sensitivity and specificity, respectively.

  11. Signatures of Selection for Environmental Adaptation and Zebu × Taurine Hybrid Fitness in East African Shorthorn Zebu

    Directory of Open Access Journals (Sweden)

    Hussain Bahbahani

    2017-06-01

    Full Text Available 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 samples from Kenya (KEASZ with more than 770,000 SNPs and sequenced the genome of a pool of 10 KEASZ. We observe an even admixed autosomal zebu × taurine genomic structure in the population. A total of 101 and 165 candidate regions of positive selection, based on genome-wide SNP analyses (meta-SS, Rsb, iHS, and ΔAF and pooled heterozygosity (Hp full genome sequence analysis, are identified, in which 35 regions are shared between them. A total of 142 functional variants, one novel, have been detected within these regions, in which 30 and 26 were classified as of zebu and African taurine origins, respectively. High density genome-wide SNP analysis of zebu × taurine admixed cattle populations from Uganda and Nigeria show that 25 of these regions are shared between KEASZ and Uganda cattle, and seven regions are shared across the KEASZ, Uganda, and Nigeria cattle. The identification of common candidate regions allows us to fine map 18 regions. These regions intersect with genes and QTL associated with reproduction and environmental stress (e.g., immunity and heat stress suggesting that the genome of the zebu × taurine admixed cattle has been uniquely selected to maximize hybrid fitness both in terms of reproduction and survivability.

  12. Transfusion safety in francophone African countries: an analysis of strategies for the medical selection of blood donors.

    Science.gov (United States)

    Tagny, Claude Tayou; Kouao, Maxime Diané; Touré, Hamane; Gargouri, Jalel; Fazul, Ahamada Said; Ouattara, Siaka; Anani, Ludovic; Othmani, Habiba; Feteke, Lochina; Dahourou, Honorine; Mbensa, Guy Olivier; Molé, Simplice; Nébié, Yacouba; Mbangue, Madeleine; Toukam, Michel; Boulahi, Mahommed Ould; Andriambelo, Lalatiana Valisoa; Rakoto, Olivat; Baby, Mounirou; Yahaya, Rakia; Bokilo, Amelia; Senyana, Florent; Mbanya, Dora; Shiboski, Caroline; Murphy, Edward L; Lefrère, Jean Jacques

    2012-01-01

    The goal of selecting a healthy blood donor is to safeguard donors and reduce the risks of infections and immunologic complications for recipients. To evaluate the blood donor selection process, a survey was conducted in 28 blood transfusion centers located in 15 francophone African countries. Data collected included availability of blood products, risk factors for infection identified among blood donor candidates, the processing of the information collected before blood collection, the review process for the medical history of blood donor candidates, and deferral criteria for donor candidates. During the year 2009, participating transfusion centers identified 366,924 blood donor candidates. A mean of 13% (range, 0%-36%) of the donor candidates were excluded based solely on their medical status. The main risk factors for blood-borne infections were having multiple sex partners, sexual intercourse with occasional partners, and religious scarification. Most transfusion centers collected this information verbally instead of having a written questionnaire. The topics least addressed were the possible complications relating to the donation, religious scarifications, and history of sickle cell anemia and hemorrhage. Only three centers recorded the temperature of the blood donors. The deferral criteria least reported were sickle cell anemia, piercing, scarification, and tattoo. The medical selection process was not performed systemically and thoroughly enough, given the regional epidemiologic risks. It is essential to identify the risk factors specific to francophone African countries and modify the current medical history questionnaires to develop a more effective and relevant selection process. © 2011 American Association of Blood Banks.

  13. Personal name in Igbo Culture: A dataset on randomly selected personal names and their statistical analysis.

    Science.gov (United States)

    Okagbue, Hilary I; Opanuga, Abiodun A; Adamu, Muminu O; Ugwoke, Paulinus O; Obasi, Emmanuela C M; Eze, Grace A

    2017-12-01

    This data article contains the statistical analysis of Igbo personal names and a sample of randomly selected of such names. This was presented as the following: 1). A simple random sampling of some Igbo personal names and their respective gender associated with each name. 2). The distribution of the vowels, consonants and letters of alphabets of the personal names. 3). The distribution of name length. 4). The distribution of initial and terminal letters of Igbo personal names. The significance of the data was discussed.

  14. The in vitro biological activity of selected South African Commiphora species.

    Science.gov (United States)

    Paraskeva, M P; van Vuuren, S F; van Zyl, R L; Davids, H; Viljoen, A M

    2008-10-28

    Ten South African Commiphora (Burseraceae) species were investigated to validate their use in traditional healing rites. The leaf and stem extracts of each species were analysed for the anti-oxidant (ABTS and DPPH assays), antimicrobial (MIC and death kinetic assays), anti-inflammatory (5-LOX assay), anticancer (SRB assay) properties, as well as the cytotoxic effects (tetrazolium-based assay). The best anti-oxidant activity (ABTS assay) was observed for the stem extracts of Commiphora tenuipetiolata IC(50)=5.10 microg/ml), Commiphora neglecta (IC(50)=7.28 microg/ml) and Commiphora mollis (IC(50)=8.82 microg/ml). Extracts generally exhibited poor anti-oxidant activity in the DPPH assay, with the exception of Commiphora schimperi (stem), Commiphora neglecta (stem), Commiphora tenuipetiolata (stem and leaf), and Commiphora edulis (stem), with IC(50) values ranging between 7.31 and 10.81 microg/ml. The stem extracts exhibited moderate to good 5-LOX inhibitory activity with Commiphora pyracanthoides (stem) displaying the greatest inhibitory effect (IC(50)=27.86+/-4.45 microg/ml). For the antimicrobial (MIC) assay, a greater selectivity was exhibited by the extracts against the Gram-positive bacteria (0.01-8.00 mg/ml) and the yeasts (0.25-8.00 mg/ml) than against the Gram-negative bacteria (1.00-8.00 mg/ml). Using death kinetic studies (time-kill studies), the rate at which Commiphora marlothii (stem) kills Staphylococcus aureus over a 24h period was determined. Mostly, a concentration-dependent antibacterial activity was observed beginning after ca. 30 min. All concentrations exhibited antibacterial activity, with complete bactericidal effect achieved by the 24(th) hour. The most active Commiphora species against the HT-29 cells (SRB anticancer assay) were Commiphora glandulosa (leaf and stem) and Commiphora marlothii (leaf). The MCF-7 cells (SRB anticancer assay) exhibited the highest sensitivity to indigenous Commiphora species, with Commiphora edulis (leaf and stem

  15. 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.

  16. 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.

  17. Assessment of selected metals in the muscle and liver of the African ...

    African Journals Online (AJOL)

    This study determined the level of manganese, zinc, copper, and nickel in the liver and muscle of the African Catfish, Clarias gariepinus from Ilushi River, Edo State, Nigeria with a view to determining the level of heavy metal contamination. The results showed that the muscles and the livers contained varying levels of the ...

  18. 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.

  19. 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 th...

  20. Simulated Performance Evaluation of a Selective Tracker Through Random Scenario Generation

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar

    2006-01-01

      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...

  1. Classification of epileptic EEG signals based on simple random sampling and sequential feature selection

    OpenAIRE

    Ghayab, Hadi Ratham Al; Li, Yan; Abdulla, Shahab; Diykh, Mohammed; Wan, Xiangkui

    2016-01-01

    Electroencephalogram (EEG) signals are used broadly in the medical fields. The main applications of EEG signals are the diagnosis and treatment of diseases such as epilepsy, Alzheimer, sleep problems and so on. This paper presents a new method which extracts and selects features from multi-channel EEG signals. This research focuses on three main points. Firstly, simple random sampling (SRS) technique is used to extract features from the time domain of EEG signals. Secondly, the sequential fea...

  2. 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.

  3. Statistical inference of selection and divergence from a time-dependent Poisson random field model.

    Directory of Open Access Journals (Sweden)

    Amei Amei

    Full Text Available We apply a recently developed time-dependent Poisson random field model to aligned DNA sequences from two related biological species to estimate selection coefficients and divergence time. We use Markov chain Monte Carlo methods to estimate species divergence time and selection coefficients for each locus. The model assumes that the selective effects of non-synonymous mutations are normally distributed across genetic loci but constant within loci, and synonymous mutations are selectively neutral. In contrast with previous models, we do not assume that the individual species are at population equilibrium after divergence. Using a data set of 91 genes in two Drosophila species, D. melanogaster and D. simulans, we estimate the species divergence time t(div = 2.16 N(e (or 1.68 million years, assuming the haploid effective population size N(e = 6.45 x 10(5 years and a mean selection coefficient per generation μ(γ = 1.98/N(e. Although the average selection coefficient is positive, the magnitude of the selection is quite small. Results from numerical simulations are also presented as an accuracy check for the time-dependent model.

  4. 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

  5. A culturally adapted telecommunication system to improve physical activity, diet quality, and medication adherence among hypertensive African-Americans: a randomized controlled trial.

    Science.gov (United States)

    Migneault, Jeffrey P; Dedier, Julien J; Wright, Julie A; Heeren, Timothy; Campbell, Marci Kramish; Morisky, Donald E; Rudd, Peter; Friedman, Robert H

    2012-02-01

    Hypertension is more prevalent and clinically severe among African-Americans than whites. Several health behaviors influence blood pressure (BP) control, but effective, accessible, culturally sensitive interventions that target multiple behaviors are lacking. We evaluated a culturally adapted, automated telephone system to help hypertensive, urban African-American adults improve their adherence to their antihypertensive medication regimen and to evidence-based guidelines for dietary behavior and physical activity. We randomized 337 hypertensive primary care patients to an 8-month automated, multi-behavior intervention or to an education-only control. Medication adherence, diet, physical activity, and BP were assessed at baseline and every 4 months for 1 year. Data were analyzed using longitudinal modeling. The intervention was associated with improvements in a measure of overall diet quality (+3.5 points, p telecommunications systems can promote self-management of diet and energy balance in urban African-Americans.

  6. Small individual loans and mental health: a randomized controlled trial among South African adults

    Directory of Open Access Journals (Sweden)

    Karlan Dean

    2008-12-01

    Full Text Available Abstract Background In the developing world, access to small, individual loans has been variously hailed as a poverty-alleviation tool – in the context of "microcredit" – but has also been criticized as "usury" and harmful to vulnerable borrowers. Prior studies have assessed effects of access to credit on traditional economic outcomes for poor borrowers, but effects on mental health have been largely ignored. Methods Applicants who had previously been rejected (n = 257 for a loan (200% annual percentage rate – APR from a lender in South Africa were randomly assigned to a "second-look" that encouraged loan officers to approve their applications. This randomized encouragement resulted in 53% of applicants receiving a loan they otherwise would not have received. All subjects were assessed 6–12 months later with questions about demographics, socio-economic status, and two indicators of mental health: the Center for Epidemiologic Studies – Depression Scale (CES-D and Cohen's Perceived Stress scale. Intent-to-treat analyses were calculated using multinomial probit regressions. Results Randomization into receiving a "second look" for access to credit increased perceived stress in the combined sample of women and men; the findings were stronger among men. Credit access was associated with reduced depressive symptoms in men, but not women. Conclusion Our findings suggest that a mechanism used to reduce the economic stress of extremely poor individuals can have mixed effects on their experiences of psychological stress and depressive symptomatology. Our data support the notion that mental health should be included as a measure of success (or failure when examining potential tools for poverty alleviation. Further longitudinal research is needed in South Africa and other settings to understand how borrowing at high interest rates affects gender roles and daily life activities. CCT: ISRCTN 10734925

  7. Small individual loans and mental health: a randomized controlled trial among South African adults.

    Science.gov (United States)

    Fernald, Lia C H; Hamad, Rita; Karlan, Dean; Ozer, Emily J; Zinman, Jonathan

    2008-12-16

    In the developing world, access to small, individual loans has been variously hailed as a poverty-alleviation tool - in the context of "microcredit" - but has also been criticized as "usury" and harmful to vulnerable borrowers. Prior studies have assessed effects of access to credit on traditional economic outcomes for poor borrowers, but effects on mental health have been largely ignored. Applicants who had previously been rejected (n = 257) for a loan (200% annual percentage rate - APR) from a lender in South Africa were randomly assigned to a "second-look" that encouraged loan officers to approve their applications. This randomized encouragement resulted in 53% of applicants receiving a loan they otherwise would not have received. All subjects were assessed 6-12 months later with questions about demographics, socio-economic status, and two indicators of mental health: the Center for Epidemiologic Studies - Depression Scale (CES-D) and Cohen's Perceived Stress scale. Intent-to-treat analyses were calculated using multinomial probit regressions. Randomization into receiving a "second look" for access to credit increased perceived stress in the combined sample of women and men; the findings were stronger among men. Credit access was associated with reduced depressive symptoms in men, but not women. Our findings suggest that a mechanism used to reduce the economic stress of extremely poor individuals can have mixed effects on their experiences of psychological stress and depressive symptomatology. Our data support the notion that mental health should be included as a measure of success (or failure) when examining potential tools for poverty alleviation. Further longitudinal research is needed in South Africa and other settings to understand how borrowing at high interest rates affects gender roles and daily life activities. CCT: ISRCTN 10734925.

  8. The portrayal of single women characters in selected African literary texts

    Directory of Open Access Journals (Sweden)

    Linda Kwatsha

    2015-03-01

    Full Text Available In this article, the portrayal of single women characters in works by a number of African women authors is critically reflected upon. These women are portrayed as strong, resistant, independent and realistic characters, who boldly resist male paternalism and dominance in order to look to the future with courage. Single women characters are presented as independent individuals rather than as kinship appendages. They are portrayed as architects of their own potential happiness rather than as passive receivers of the dictates of patriarchy. The article will also show that women characters account for their own values, rather than subserviently surrender to stereotypical conventions. African women writers portray single women characters as having the professional and economic means to look after themselves. This portrayal of women characters is part of a debate that translates itself to contemporary everyday philosophical social theory.

  9. On-farm testing of selected cassava clones | Saleh | African Crop ...

    African Journals Online (AJOL)

    ... une évaluation participative des essais. Les fermiers ont préféré les clones ZNZ/98/036, ZNZ/98/034 et ZNZ/98/084 à cause de la concentration en sucre, la résistance aux maladies, les rendements des raciness, et le contenu en matière sèche. Mots clés: Maladies, Manihot esculenta, pestes. African Crop Science Journal ...

  10. The providing resources to enhance African American patients’ readiness to make decisions about kidney disease (PREPARED study: protocol of a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Ephraim Patti L

    2012-10-01

    Full Text Available Abstract Background Living related kidney transplantation (LRT is underutilized, particularly among African Americans. The effectiveness of informational and financial interventions to enhance informed decision-making among African Americans with end stage renal disease (ESRD and improve rates of LRT is unknown. Methods/design We report the protocol of the Providing Resources to Enhance African American Patients’ Readiness to Make Decisions about Kidney Disease (PREPARED Study, a two-phase study utilizing qualitative and quantitative research methods to design and test the effectiveness of informational (focused on shared decision-making and financial interventions to overcome barriers to pursuit of LRT among African American patients and their families. Study Phase I involved the evidence-based development of informational materials as well as a financial intervention to enhance African American patients’ and families’ proficiency in shared decision-making regarding LRT. In Study Phase 2, we are currently conducting a randomized controlled trial in which patients with new-onset ESRD receive 1 usual dialysis care by their nephrologists, 2 the informational intervention (educational video and handbook, or 3 the informational intervention in addition to the option of participating in a live kidney donor financial assistance program. The primary outcome of the randomized controlled trial will include patients’ self-reported rates of consideration of LRT (including family discussions of LRT, patient-physician discussions of LRT, and identification of a LRT donor. Discussion Results from the PREPARED study will provide needed evidence on ways to enhance the decision to pursue LRT among African American patients with ESRD. Trial registration ClinicalTrials.gov NCT01439516

  11. Effect of non-random mating on genomic and BLUP selection schemes

    Directory of Open Access Journals (Sweden)

    Nirea Kahsay G

    2012-04-01

    Full Text Available Abstract Background The risk of long-term unequal contribution of mating pairs to the gene pool is that deleterious recessive genes can be expressed. Such consequences could be alleviated by appropriately designing and optimizing breeding schemes i.e. by improving selection and mating procedures. Methods We studied the effect of mating designs, random, minimum coancestry and minimum covariance of ancestral contributions on rate of inbreeding and genetic gain for schemes with different information sources, i.e. sib test or own performance records, different genetic evaluation methods, i.e. BLUP or genomic selection, and different family structures, i.e. factorial or pair-wise. Results Results showed that substantial differences in rates of inbreeding due to mating design were present under schemes with a pair-wise family structure, for which minimum coancestry turned out to be more effective to generate lower rates of inbreeding. Specifically, substantial reductions in rates of inbreeding were observed in schemes using sib test records and BLUP evaluation. However, with a factorial family structure, differences in rates of inbreeding due mating designs were minor. Moreover, non-random mating had only a small effect in breeding schemes that used genomic evaluation, regardless of the information source. Conclusions It was concluded that minimum coancestry remains an efficient mating design when BLUP is used for genetic evaluation or when the size of the population is small, whereas the effect of non-random mating is smaller in schemes using genomic evaluation.

  12. Emulsion PCR: a high efficient way of PCR amplification of random DNA libraries in aptamer selection.

    Directory of Open Access Journals (Sweden)

    Keke Shao

    Full Text Available Aptamers are short RNA or DNA oligonucleotides which can bind with different targets. Typically, they are selected from a large number of random DNA sequence libraries. The main strategy to obtain aptamers is systematic evolution of ligands by exponential enrichment (SELEX. Low efficiency is one of the limitations for conventional PCR amplification of random DNA sequence library in aptamer selection because of relative low products and high by-products formation efficiency. Here, we developed emulsion PCR for aptamer selection. With this method, the by-products formation decreased tremendously to an undetectable level, while the products formation increased significantly. Our results indicated that by-products in conventional PCR amplification were from primer-product and product-product hybridization. In emulsion PCR, we can completely avoid the product-product hybridization and avoid the most of primer-product hybridization if the conditions were optimized. In addition, it also showed that the molecule ratio of template to compartment was crucial to by-product formation efficiency in emulsion PCR amplification. Furthermore, the concentration of the Taq DNA polymerase in the emulsion PCR mixture had a significant impact on product formation efficiency. So, the results of our study indicated that emulsion PCR could improve the efficiency of SELEX.

  13. Novel Zn2+-chelating peptides selected from a fimbria-displayed random peptide library

    DEFF Research Database (Denmark)

    Kjærgaard, Kristian; Schembri, Mark; Klemm, Per

    2001-01-01

    H adhesin. FimH is a component of the fimbrial organelle that can accommodate and display a diverse range of peptide sequences on the E. coli cell surface. In this study we have constructed a random peptide library in FimH. The library, consisting of similar to 40 million individual clones, was screened...... for peptide sequences that conferred on recombinant cells the ability to bind Zn2+. By serial selection, sequences that exhibited various degrees of binding affinity and specificity toward Zn2+ were enriched. None of the isolated sequences showed similarity to known Zn2+-binding proteins, indicating...

  14. Large-scale selective sweep among Segregation Distorter chromosomes in African populations of Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Daven C Presgraves

    2009-05-01

    Full Text Available Segregation Distorter (SD is a selfish, coadapted gene complex on chromosome 2 of Drosophila melanogaster that strongly distorts Mendelian transmission; heterozygous SD/SD(+ males sire almost exclusively SD-bearing progeny. Fifty years of genetic, molecular, and theory work have made SD one of the best-characterized meiotic drive systems, but surprisingly the details of its evolutionary origins and population dynamics remain unclear. Earlier analyses suggested that the SD system arose recently in the Mediterranean basin and then spread to a low, stable equilibrium frequency (1-5% in most natural populations worldwide. In this report, we show, first, that SD chromosomes occur in populations in sub-Saharan Africa, the ancestral range of D. melanogaster, at a similarly low frequency (approximately 2%, providing evidence for the robustness of its equilibrium frequency but raising doubts about the Mediterranean-origins hypothesis. Second, our genetic analyses reveal two kinds of SD chromosomes in Africa: inversion-free SD chromosomes with little or no transmission advantage; and an African-endemic inversion-bearing SD chromosome, SD-Mal, with a perfect transmission advantage. Third, our population genetic analyses show that SD-Mal chromosomes swept across the African continent very recently, causing linkage disequilibrium and an absence of variability over 39% of the length of the second chromosome. Thus, despite a seemingly stable equilibrium frequency, SD chromosomes continue to evolve, to compete with one another, or evade suppressors in the genome.

  15. Large-scale selective sweep among Segregation Distorter chromosomes in African populations of Drosophila melanogaster.

    Science.gov (United States)

    Presgraves, Daven C; Gérard, Pierre R; Cherukuri, Anjuli; Lyttle, Terrence W

    2009-05-01

    Segregation Distorter (SD) is a selfish, coadapted gene complex on chromosome 2 of Drosophila melanogaster that strongly distorts Mendelian transmission; heterozygous SD/SD(+) males sire almost exclusively SD-bearing progeny. Fifty years of genetic, molecular, and theory work have made SD one of the best-characterized meiotic drive systems, but surprisingly the details of its evolutionary origins and population dynamics remain unclear. Earlier analyses suggested that the SD system arose recently in the Mediterranean basin and then spread to a low, stable equilibrium frequency (1-5%) in most natural populations worldwide. In this report, we show, first, that SD chromosomes occur in populations in sub-Saharan Africa, the ancestral range of D. melanogaster, at a similarly low frequency (approximately 2%), providing evidence for the robustness of its equilibrium frequency but raising doubts about the Mediterranean-origins hypothesis. Second, our genetic analyses reveal two kinds of SD chromosomes in Africa: inversion-free SD chromosomes with little or no transmission advantage; and an African-endemic inversion-bearing SD chromosome, SD-Mal, with a perfect transmission advantage. Third, our population genetic analyses show that SD-Mal chromosomes swept across the African continent very recently, causing linkage disequilibrium and an absence of variability over 39% of the length of the second chromosome. Thus, despite a seemingly stable equilibrium frequency, SD chromosomes continue to evolve, to compete with one another, or evade suppressors in the genome.

  16. AfroDb: a select highly potent and diverse natural product library from African medicinal plants.

    Directory of Open Access Journals (Sweden)

    Fidele Ntie-Kang

    Full Text Available Computer-aided drug design (CADD often involves virtual screening (VS of large compound datasets and the availability of such is vital for drug discovery protocols. We assess the bioactivity and "drug-likeness" of a relatively small but structurally diverse dataset (containing >1,000 compounds from African medicinal plants, which have been tested and proven a wide range of biological activities. The geographical regions of collection of the medicinal plants cover the entire continent of Africa, based on data from literature sources and information from traditional healers. For each isolated compound, the three dimensional (3D structure has been used to calculate physico-chemical properties used in the prediction of oral bioavailability on the basis of Lipinski's "Rule of Five". A comparative analysis has been carried out with the "drug-like", "lead-like", and "fragment-like" subsets, as well as with the Dictionary of Natural Products. A diversity analysis has been carried out in comparison with the ChemBridge diverse database. Furthermore, descriptors related to absorption, distribution, metabolism, excretion and toxicity (ADMET have been used to predict the pharmacokinetic profile of the compounds within the dataset. Our results prove that drug discovery, beginning with natural products from the African flora, could be highly promising. The 3D structures are available and could be useful for virtual screening and natural product lead generation programs.

  17. Selective primary health care: strategies for control of disease in the developing world. VIII. African trypanosomiasis.

    Science.gov (United States)

    Molyneux, D H

    1983-01-01

    African trypanosomiasis in humans is caused by trypanosomes, parasitic protozoa that inhabit the blood and tissue spaces. Humans are infected by the bite of the tsetse (Glossina species), which itself acquires the parasites from human or animal hosts. The vector and the disease are confined to sub-saharan Africa where the disease occurs in endemic foci from which epidemics arise. Two forms of African trypanosomiasis in humans are recognized and both are fatal if left untreated. Control strategy is dependent on the capacity of the public health services to diagnose and treat cases, and the maintenance of surveillance is essential if epidemics are to be prevented. In epidemics this strategy should be extended to include vector-control measures to break transmission of the disease while cases continue to be diagnosed and treated. Eradication of the vector is not feasible nor can animal reservoirs be eliminated. National authorities must thus maintain surveillance to reduce the human reservoir of infection in order for low levels of endemicity, particularly in areas where epidemics have occurred in the past, to be retained.

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

    Science.gov (United States)

    Fox, Eric W; Hill, Ryan A; Leibowitz, Scott G; Olsen, Anthony R; Thornbrugh, Darren J; Weber, Marc H

    2017-07-01

    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 data sets, there is limited guidance on variable selection methods for RF modeling. Typically, either a preselected set of predictor variables are used or stepwise procedures are employed which iteratively remove variables according to their importance measures. This paper investigates the application of variable selection methods to RF models for predicting probable biological stream condition. Our motivating data set consists of the good/poor condition of n = 1365 stream survey sites from the 2008/2009 National Rivers and Stream Assessment, and a large set (p = 212) of landscape features from the StreamCat data set as potential predictors. We compare two types of RF models: a full variable set model with all 212 predictors and a reduced variable set model selected using a backward elimination approach. We assess model accuracy using RF's internal out-of-bag estimate, and a cross-validation procedure with validation folds external to the variable selection process. We also assess the stability of the spatial predictions generated by the RF models to changes in the number of predictors and argue that model selection needs to consider both accuracy and stability. The results suggest that RF modeling is robust to the inclusion of many variables of moderate to low importance. We found no substantial improvement in cross-validated accuracy as a result of variable reduction. Moreover, the backward elimination procedure tended to select too few variables and exhibited numerous issues such as upwardly biased out-of-bag accuracy estimates and instabilities in the spatial predictions. We use simulations to further support and generalize results from the analysis of real data. A main purpose of this work is to elucidate issues of model selection bias and instability to ecologists interested in

  19. PReFerSim: fast simulation of demography and selection under the Poisson Random Field model.

    Science.gov (United States)

    Ortega-Del Vecchyo, Diego; Marsden, Clare D; Lohmueller, Kirk E

    2016-11-15

    The Poisson Random Field (PRF) model has become an important tool in population genetics to study weakly deleterious genetic variation under complicated demographic scenarios. Currently, there are no freely available software applications that allow simulation of genetic variation data under this model. Here we present PReFerSim, an ANSI C program that performs forward simulations under the PRF model. PReFerSim models changes in population size, arbitrary amounts of inbreeding, dominance and distributions of selective effects. Users can track summaries of genetic variation over time and output trajectories of selected alleles. PReFerSim is freely available at: https://github.com/LohmuellerLab/PReFerSim CONTACT: klohmueller@ucla.eduSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. 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

  1. 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.

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

    Directory of Open Access Journals (Sweden)

    Willie T. Chinyamurindi

    2010-03-01

    Full Text Available Orientation: Technology enhanced training is becoming popular as a means for the training of soft skills, especially in work-related environments. Men and women who use this type of training encounter some challenges with regard to their usage.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

  3. Ethnopharmacological versus random plant selection methods for the evaluation of the antimycobacterial activity

    Directory of Open Access Journals (Sweden)

    Danilo R. Oliveira

    2011-05-01

    Full Text Available The municipality of Oriximiná, Brazil, has 33 quilombola communities in remote areas, endowed with wide experience in the use of medicinal plants. An ethnobotanical survey was carried out in five of these communities. A free-listing method directed for the survey of species locally indicated against Tuberculosis and lung problems was also applied. Data were analyzed by quantitative techniques: saliency index and major use agreement. Thirty four informants related 254 ethnospecies. Among these, 43 were surveyed for possible antimycobacterial activity. As a result of those informations, ten species obtained from the ethnodirected approach (ETHNO and eighteen species obtained from the random approach (RANDOM were assayed against Mycobacterium tuberculosis by the microdilution method, using resazurin as an indicator of cell viability. The best results for antimycobacterial activity were obtained of some plants selected by the ethnopharmacological approach (50% ETHNO x 16,7% RANDOM. These results can be even more significant if we consider that the therapeutic success obtained among the quilombola practice is complex, being the use of some plants acting as fortifying agents, depurative, vomitory, purgative and bitter remedy, especially to infectious diseases, of great importance to the communities in the curing or recovering of health as a whole.

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

    Science.gov (United States)

    Kapwata, Thandi; Gebreslasie, Michael T

    2016-11-16

    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.

  5. 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.

  6. Selecting the appropriate pacing mode for patients with sick sinus syndrome: evidence from randomized clinical trials.

    Science.gov (United States)

    Albertsen, A E; Nielsen, J C

    2003-12-01

    Several observational studies have indicated that selection of pacing mode may be important for the clinical outcome in patients with symptomatic bradycardia, affecting the development of atrial fibrillation (AF), thromboembolism, congestive heart failure, mortality and quality of life. In this paper we present and discuss the most recent data from six randomized trials on mode selection in patients with sick sinus syndrome (SSS). In pacing mode selection, VVI(R) pacing is the least attractive solution, increasing the incidence of AF and-as compared with AAI(R) pacing, also the incidence of heart failure, thromboembolism and death. VVI(R) pacing should not be used as the primary pacing mode in patients with SSS, who haven't chronic AF. AAIR pacing is superior to DDDR pacing, reducing AF and preserving left ventricular function. Single site right ventricular pacing-VVI(R) or DDD(R) mode-causes an abnormal ventricular activation and contraction (called ventricular desynchronization), which results in a reduced left ventricular function. Despite the risk of AV block, we consider AAIR pacing to be the optimal pacing mode for isolated SSS today and an algorithm to select patients for AAIR pacing is suggested. Trials on new pacemaker algorithms minimizing right ventricular pacing as well as trials testing alternative pacing sites and multisite pacing to reduce ventricular desynchronization can be expected within the next years.

  7. 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

  8. 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.

  9. 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.

  10. Feature selection for outcome prediction in oesophageal cancer using genetic algorithm and random forest classifier.

    Science.gov (United States)

    Paul, Desbordes; Su, Ruan; Romain, Modzelewski; Sébastien, Vauclin; Pierre, Vera; Isabelle, Gardin

    2017-09-01

    The outcome prediction of patients can greatly help to personalize cancer treatment. A large amount of quantitative features (clinical exams, imaging, …) are potentially useful to assess the patient outcome. The challenge is to choose the most predictive subset of features. In this paper, we propose a new feature selection strategy called GARF (genetic algorithm based on random forest) extracted from positron emission tomography (PET) images and clinical data. The most relevant features, predictive of the therapeutic response or which are prognoses of the patient survival 3 years after the end of treatment, were selected using GARF on a cohort of 65 patients with a local advanced oesophageal cancer eligible for chemo-radiation therapy. The most relevant predictive results were obtained with a subset of 9 features leading to a random forest misclassification rate of 18±4% and an areas under the of receiver operating characteristic (ROC) curves (AUC) of 0.823±0.032. The most relevant prognostic results were obtained with 8 features leading to an error rate of 20±7% and an AUC of 0.750±0.108. Both predictive and prognostic results show better performances using GARF than using 4 other studied methods. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. RESPONSE TO SELECTION FOR BODY WEIGHT IN THE THIRD GENERATION OF MASS SELECTION OF THE AFRICAN CATFISH (Clarias gariepinus AT RESEARCH INSTITUTE FOR FISH BREEDING SUKAMANDI

    Directory of Open Access Journals (Sweden)

    Bambang Iswanto

    2016-12-01

    Full Text Available Genetic improvement of the African catfish (Clarias gariepinus in Indonesia for increasing growth performance has been conducted by Research Institute for Fish Breeding at Sukamandi through mass selection. Collection and characterizations of the founder populations, building the synthetic base population, first generation and second generation through mass selection were conducted during 2010-2013. Later, in 2014 it was followed by building the third generation. The present study aimed to find out the genetic gain in the third generation in term of response to selection for body weight. Fifty-two pairs of the selected (fast growing individuals from the second generation were mated to produce the third generation. As a comparison, five pairs of average-sized individuals were mated to produce the control population, as a second generation representative. Larval rearing, nursery and grow-out phases were respectively held for 25 days in the aquaria, 30 days in the concrete ponds and 60 days in the concrete ponds. At the end of each phase, individual samplings of body weight were undertaken. The results showed that mean body weight of the third generation was higher than that of control population at the end of larval rearing phase (0.21 ± 0.26 g versus 0.20 ± 0.15 g, nursery phase (6.12 ± 2.93 g versus 5.80 ± 3.50 g and grow-out phase (198.67 ± 82.82 g versus 165.22 ± 71.09 g. Those results revealed that response to selection for body weight of the third generation was positive, i.e. about 20.24% (33.45 g.

  12. Role of Select Genetic Variants in Lung Cancer Risk in African Americans

    Science.gov (United States)

    Spitz, Margaret R.; Amos, Christopher I.; Land, Susan; Wu, Xifeng; Dong, Qiong; Wenzlaff, Angela S.; Schwartz, Ann G.

    2013-01-01

    Introduction Black/white disparities in lung cancer incidence and mortality mandate an evaluation of underlying biological differences. We have previously shown higher risks of lung cancer associated with prior emphysema in African American compared with white lung cancer patients. Methods We therefore evaluated a panel of 1440 inflammatory gene variants in a two phase analysis (discovery and replication), added top GWAS lung cancer hits from Caucasian populations, and 28 SNPs from a published gene panel. The discovery set (477 self-designated African Americans cases, 366 controls matched on age, ethnicity, and gender) were from Houston, Texas. The external replication set (330 cases, 342 controls) was from the EXHALE study at Wayne State University. Results In discovery, 154 inflammation SNPs were significant (P<0.05) on univariate analysis, as was one of the gene panel SNPs (rs308738 in REV1, P=0.0013), and three GWAS hits, rs16969968 P=0.0014 and rs10519203 P=0.0003 in the 15q locus and rs2736100, the HTERT locus, P=0.0002. One inflammation SNP, rs950286, was successfully replicated with a concordant odds ratio of 1.46(1.14-1.87) in discovery, 1.37(1.05-1.77) in replication, and a combined OR of 1.40 (1.17-1.68). This SNP is intergenic between IRF4 and EXOC2 genes. We also constructed and validated epidemiologic and extended risk prediction models. The AUC for the epidemiologic discovery model was 0.77 and 0.80 for the extended model. For the combined datasets, the AUC values were 0.75 and 0.76, respectively. Conclusion As has been reported for other cancer sites and populations, incorporating top genetic hits into risk prediction models, provides little improvement in model performance and no clinical relevance. PMID:23454887

  13. Role of selected genetic variants in lung cancer risk in African Americans.

    Science.gov (United States)

    Spitz, Margaret R; Amos, Christopher I; Land, Susan; Wu, Xifeng; Dong, Qiong; Wenzlaff, Angela S; Schwartz, Ann G

    2013-04-01

    Black/white disparities in lung cancer incidence and mortality mandate an evaluation of underlying biological differences. We have previously shown higher risks of lung cancer associated with prior emphysema in African American compared with white patients with lung cancer. We therefore evaluated a panel of 1440 inflammatory gene variants in a two-phase analysis (discovery and replication), added top genome-wide association studies (GWAS) lung cancer hits from white populations, and 28 single-nucleotide polymorphisms (SNPs) from a published gene panel. The discovery set (477 self-designated African Americans cases, 366 controls matched on age, ethnicity, and gender) were from Houston, Texas. The external replication set (330 cases and 342 controls) was from the EXHALE study at Wayne State University. In discovery, 154 inflammation SNPs were significant (p < 0.05) on univariate analysis, as was one of the gene panel SNPs (rs308738 in REV1, p = 0.0013), and three GWAS hits, rs16969968 p = 0.0014 and rs10519203 p = 0.0003 in the 15q locus and rs2736100, in the HTERT locus, p = 0.0002. One inflammation SNP, rs950286, was successfully replicated with a concordant odds ratio of 1.46 (1.14-1.87) in discovery, 1.37 (1.05-1.77) in replication, and a combined odds ratio of 1.40 (1.17-1.68). This SNP is intergenic between IRF4 and EXOC2 genes. We also constructed and validated epidemiologic and extended risk prediction models. The area under the curve (AUC) for the epidemiologic discovery model was 0.77 and 0.80 for the extended model. For the combined datasets, the AUC values were 0.75 and 0.76, respectively. As has been reported for other cancer sites and populations, incorporating top genetic hits into risk prediction models, provides little improvement in model performance and no clinical relevance.

  14. 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

  15. 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 .

  16. Selected African American First-Time Teenage Mothers' Perceptions of Nurse Caring Behaviors During The Postpartum Period

    OpenAIRE

    Danita Renae Potter; Esther H. Condon; Arlene J. Montgomery; Toni Sims Muhammad; Zina T. McGee

    2012-01-01

    The purpose of this study was to explore and describe African American teen mothers’ perceptions of nurse caring behaviors during the postpartum period in a rural southern state. African Americans have unique cultural needs; thus, it is critical for the science of nursing to explore and describe African American teenage mothers’ perceptions of nurse caring behaviors during the postpartum period. By exploring and describing African American first-time teenage mothers’ perceptions of nurse cari...

  17. Body size perception of African women (25-44 years) in Manguang ...

    African Journals Online (AJOL)

    The main objective of this study was to gain insight into the body size perception of African women in the Mangaung area of the Central Free State. A representative sample of 500 African women (age groups 25-34 years and 35-44 years) was randomly selected to participate. The sample was subjected to anthropometrical ...

  18. 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...

  19. 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.

  20. Prevalence of foodborne pathogens in food from selected African countries - A meta-analysis.

    Science.gov (United States)

    Paudyal, Narayan; Anihouvi, Victor; Hounhouigan, Joseph; Matsheka, Maitshwarelo Ignatius; Sekwati-Monang, Bonno; Amoa-Awua, Wisdom; Atter, Amy; Ackah, Nina Bernice; Mbugua, Samuel; Asagbra, Agnes; Abdelgadir, Warda; Nakavuma, Jesca; Jakobsen, Mogens; Fang, Weihuan

    2017-05-16

    Food safety information in the African region is insufficient and fragmented due to lack of surveillance, documentation and reporting, thereby resulting in inefficient utilization of resources, duplication of activities, and lack of synergy among the countries of the region. This paper reviews the prevalence of foodborne pathogens in seven African countries (Benin, Botswana, Ghana, Kenya, Nigeria, Sudan and Uganda) from papers in regional or international journals published between January 2000 and December 2015. One hundred and sixteen publications that dealt with food microbiology were reviewed for general analysis, while 66 papers on contamination of pathogenic bacteria were used for meta-analysis of prevalence. The food items were split into two categories: raw foods and ready-to-eat (RTE) foods (including street food and beverages) for meta-analysis. Majority of the reviewed studies (67.2%, 78/116) dealt with food of animal origin: 38.8% for meat and eggs, 17.2% for dairy products and 11.2% for aquatic products. Only 8.6% examined foods of plant origin (fruits and vegetables). The remaining 24.1% was the composite RTE food and beverages. Enterobacteriaceae, Escherichia coli, Salmonella, Staphylococcus aureus and Listeria monocytogenes were the most frequently reported organisms in those studies. Although the data were highly heterogeneous, a striking feature is high prevalence of the major pathogens in RTE foods, almost as high as in raw foods. E. coli averaged at 37.6% in raw foods and 31.6% in RTE foods. The corresponding prevalence for Salmonella was 19.9% vs 21.7%; S. aureus, 27.8% vs 25.1% and L. monocytogenes, 19.5% vs 6.7%. The average prevalence of foodborne pathogens in these countries was 34.2% (29.0-39.3%). Differences in food types as well as non-uniform protocols for sampling and identification might have contributed to high heterogeneity (I 2 >97%) although some high prevalence data could be factual with extensive varieties of raw and RTE foods

  1. 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…

  2. Does the Use of a Decision Aid Improve Decision Making in Prosthetic Heart Valve Selection? A Multicenter Randomized Trial

    NARCIS (Netherlands)

    Korteland, Nelleke M.; Ahmed, Yunus; Koolbergen, David R.; Brouwer, Marjan; de Heer, Frederiek; Kluin, Jolanda; Bruggemans, Eline F.; Klautz, Robert J. M.; Stiggelbout, Anne M.; Bucx, Jeroen J. J.; Roos-Hesselink, Jolien W.; Polak, Peter; Markou, Thanasie; van den Broek, Inge; Ligthart, Rene; Bogers, Ad J. J. C.; Takkenberg, Johanna J. M.

    2017-01-01

    A Dutch online patient decision aid to support prosthetic heart valve selection was recently developed. A multicenter randomized controlled trial was conducted to assess whether use of the patient decision aid results in optimization of shared decision making in prosthetic heart valve selection. In

  3. Women's empowerment and choice of contraceptive methods in selected African countries.

    Science.gov (United States)

    Do, Mai; Kurimoto, Nami

    2012-03-01

    It is generally believed that women's lack of decision-making power may restrict their use of modern contraceptives. However, few studies have examined the different dimensions of women's empowerment and contraceptive use in African countries. Data came from the latest round of Demographic and Health Surveys conducted between 2006 and 2008 in Namibia, Zambia, Ghana and Uganda. Responses from married or cohabiting women aged 15-49 were analyzed for six dimensions of empowerment and the current use of female-only methods or couple methods. Bivariate and multivariate multinomial regressions were used to identify associations between the empowerment dimensions and method use. Positive associations were found between the overall empowerment score and method use in all countries (relative risk ratios, 1.1-1.3). In multivariate analysis, household economic decision making was associated with the use of either female-only or couple methods (1.1 for all), as was agreement on fertility preferences (1.3-1.6) and the ability to negotiate sexual activity (1.1-1.2). In Namibia, women's negative attitudes toward domestic violence were correlated with the use of couple methods (1.1). Intervention programs aimed at increasing contraceptive use may need to involve different approaches, including promoting couples' discussion of fertility preferences and family planning, improving women's self-efficacy in negotiating sexual activity and increasing their economic independence.

  4. Selective outcome reporting and sponsorship in randomized controlled trials in IVF and ICSI.

    Science.gov (United States)

    Braakhekke, M; Scholten, I; Mol, F; Limpens, J; Mol, B W; van der Veen, F

    2017-10-01

    Are randomized controlled trials (RCTs) on IVF and ICSI subject to selective outcome reporting and is this related to sponsorship? There are inconsistencies, independent from sponsorship, in the reporting of primary outcome measures in the majority of IVF and ICSI trials, indicating selective outcome reporting. RCTs are subject to bias at various levels. Of these biases, selective outcome reporting is particularly relevant to IVF and ICSI trials since there is a wide variety of outcome measures to choose from. An established cause of reporting bias is sponsorship. It is, at present, unknown whether RCTs in IVF/ICSI are subject to selective outcome reporting and whether this is related with sponsorship. We systematically searched RCTs on IVF and ICSI published between January 2009 and March 2016 in MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials and the publisher subset of PubMed. We analysed 415 RCTs. Per included RCT, we extracted data on impact factor of the journal, sample size, power calculation, and trial registry and thereafter data on primary outcome measure, the direction of trial results and sponsorship. Of the 415 identified RCTs, 235 were excluded for our primary analysis, because the sponsorship was not reported. Of the 180 RCTs included in our analysis, 7 trials did not report on any primary outcome measure and 107 of the remaining 173 trials (62%) reported on surrogate primary outcome measures. Of the 114 registered trials, 21 trials (18%) provided primary outcomes in their manuscript that were different from those in the trial registry. This indicates selective outcome reporting. We found no association between selective outcome reporting and sponsorship. We ran additional analyses to include the trials that had not reported sponsorship and found no outcomes that differed from our primary analysis. Since the majority of the trials did not report on sponsorship, there is a risk on sampling bias. IVF and ICSI trials are subject, to

  5. Active classifier selection for RGB-D object categorization using a Markov random field ensemble method

    Science.gov (United States)

    Durner, Maximilian; Márton, Zoltán.; Hillenbrand, Ulrich; Ali, Haider; Kleinsteuber, Martin

    2017-03-01

    In this work, a new ensemble method for the task of category recognition in different environments is presented. The focus is on service robotic perception in an open environment, where the robot's task is to recognize previously unseen objects of predefined categories, based on training on a public dataset. We propose an ensemble learning approach to be able to flexibly combine complementary sources of information (different state-of-the-art descriptors computed on color and depth images), based on a Markov Random Field (MRF). By exploiting its specific characteristics, the MRF ensemble method can also be executed as a Dynamic Classifier Selection (DCS) system. In the experiments, the committee- and topology-dependent performance boost of our ensemble is shown. Despite reduced computational costs and using less information, our strategy performs on the same level as common ensemble approaches. Finally, the impact of large differences between datasets is analyzed.

  6. 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

  7. Clinical outcome of intracytoplasmic injection of spermatozoa morphologically selected under high magnification: a prospective randomized study.

    Science.gov (United States)

    Balaban, Basak; Yakin, Kayhan; Alatas, Cengiz; Oktem, Ozgur; Isiklar, Aycan; Urman, Bulent

    2011-05-01

    Recent evidence shows that the selection of spermatozoa based on the analysis of morphology under high magnification (×6000) may have a positive impact on embryo development in cases with severe male factor infertility and/or previous implantation failures. The objective of this prospective randomized study was to compare the clinical outcome of 87 intracytoplasmic morphologically selected sperm injection (IMSI) cycles with 81 conventional intracytoplasmic sperm injection (ICSI) cycles in an unselected infertile population. IMSI did not provide a significant improvement in the clinical outcome compared with ICSI although there were trends for higher implantation (28.9% versus 19.5%), clinical pregnancy (54.0% versus 44.4%) and live birth rates (43.7% versus 38.3%) in the IMSI group. However, severe male factor patients benefited from the IMSI procedure as shown by significantly higher implantation rates compared with their counterparts in the ICSI group (29.6% versus 15.2%, P=0.01). These results suggest that IMSI may improve IVF success rates in a selected group of patients with male factor infertility. New technological developments enable the real time examination of motile spermatozoa with an inverted light microscope equipped with high-power differential interference contrast optics, enhanced by digital imaging. High magnification (over ×6000) provides the identification of spermatozoa with a normal nucleus and nuclear content. Intracytoplasmic injection of spermatozoa selected according to fine nuclear morphology under high magnification may improve the clinical outcome in cases with severe male factor infertility. Copyright © 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  8. A Comparison of Dietary Habits between Recreational Runners and a Randomly Selected Adult Population in Slovenia.

    Science.gov (United States)

    Škof, Branko; Rotovnik Kozjek, Nada

    2015-09-01

    The aim of the study was to compare the dietary habits of recreational runners with those of a random sample of the general population. We also wanted to determine the influence of gender, age and sports performance of recreational runners on their basic diet and compliance with recommendations in sports nutrition. The study population consisted of 1,212 adult Slovenian recreational runners and 774 randomly selected residents of Slovenia between the ages of 18 and 65 years. The data on the dietary habits of our subjects was gathered by means of two questionnaires. The following parameters were evaluated: the type of diet, a food pattern, and the frequency of consumption of individual food groups, the use of dietary supplements, fluid intake, and alcohol consumption. Recreational runners had better compliance with recommendations for healthy nutrition than the general population. This pattern increased with the runner's age and performance level. Compared to male runners, female runners ate more regularly and had a more frequent consumption of food groups associated with a healthy diet (fruit, vegetables, whole grain foods, and low-fat dairy products). The consumption of simple sugars and use of nutritional supplements by well-trained runners was inadequate with values recommended for physically active individuals. Recreational runners are an exemplary population group that actively seeks to adopt a healthier lifestyle.

  9. Radiographic methods used before removal of mandibular third molars among randomly selected general dental clinics.

    Science.gov (United States)

    Matzen, Louise H; Petersen, Lars B; Wenzel, Ann

    2016-01-01

    To assess radiographic methods and diagnostically sufficient images used before removal of mandibular third molars among randomly selected general dental clinics. Furthermore, to assess factors predisposing for an additional radiographic examination. 2 observers visited 18 randomly selected clinics in Denmark and studied patient files, including radiographs of patients who had their mandibular third molar(s) removed. The radiographic unit and type of receptor were registered. A diagnostically sufficient image was defined as the whole tooth and mandibular canal were displayed in the radiograph (yes/no). Overprojection between the tooth and mandibular canal (yes/no) and patient-reported inferior alveolar nerve sensory disturbances (yes/no) were recorded. Regression analyses tested if overprojection between the third molar and the mandibular canal and an insufficient intraoral image predisposed for additional radiographic examination(s). 1500 mandibular third molars had been removed; 1090 had intraoral, 468 had panoramic and 67 had CBCT examination. 1000 teeth were removed after an intraoral examination alone, 433 after panoramic examination and 67 after CBCT examination. 90 teeth had an additional examination after intraoral. Overprojection between the tooth and mandibular canal was a significant factor (p < 0.001, odds ratio = 3.56) for an additional examination. 63.7% of the intraoral images were sufficient and 36.3% were insufficient, with no significant difference between images performed with phosphor plates and solid-state sensors (p = 0.6). An insufficient image predisposed for an additional examination (p = 0.008, odds ratio = 1.8) but was only performed in 11% of the cases. Most mandibular third molars were removed based on an intraoral examination although 36.3% were insufficient.

  10. Recruitment and Selection of Foreign Professionals In the South African Job Market: Procedures and Processes

    Directory of Open Access Journals (Sweden)

    Chao Nkhungulu Mulenga

    2007-07-01

    Full Text Available This study investigated procedures and processes used in the selection of prospective foreign applicants by recruitment agencies in South Africa. An electronic survey was distributed to the accessible population of 244 agencies on a national employment website, yielding 57 respondents. The results indicate that the recruitment industry does not have standard, well articulated procedures for identifying and selecting prospective foreign employees and considered processing foreign applicants difficult. Difficulties with the Department of Home Affairs were a major hindrance to recruiting foreign applicants.

  11. Serosurvey for selected viral diseases and demography of African wild dogs in Tanzania.

    Science.gov (United States)

    Creel, S; Creel, N M; Munson, L; Sanderlin, D; Appel, M J

    1997-10-01

    African wild dogs (Lycaon pictus) are endangered, with only 3,000-5,000 remaining in the wild. It is believed that wild dogs are unusually vulnerable to viral diseases, particularly rabies and canine distemper (CDV). However, canine distemper has been confirmed by laboratory diagnosis in only one free-living wild dog. The 43,000 km2 Selous Game Reserve (SGR; Tanzania) holds approximately 900 adult wild dogs. In a study area of 2,600 km2, the population maintained high density (> or = 1 dog/20.5 km2) from 1991 to 1996. The population was stable, varying 18% below and 9% above the mean density over the 6-yr period. Serum samples (n = 22) collected over 3 yr showed that most individuals were exposed to CDV (59%:95% confidence interval = 43-76% seropositive) and canine parvovirus (68%:95% CI = 54-81% seropositive), although none were seropositive for rabies (0%:95% CI = 0-17%). CDV titers were positively related to age, with no seropositive dogs younger than 1.9 yr. At least five of 13 dogs positive for CDV seroconverted during the study. Dogs with high CDV titers did not survive better in the years after sampling (mean survival +/- SE for those that died = 638 +/- 92 days,). Variation in mean litter size was inversely related to CPV exposure in the SGR and elsewhere. Annual mortality rates were low in comparison to other populations for all age classes (pups: 31 +/- 8%, n = 127, yearlings: 22 +/- 10%, n = 93, adults: 20 +/- 6%, n = 235). Annual mortality rates fluctuated little between 1992 and 1996. These data show that wild dog populations, like those of other canids, can remain stable and demographically healthy despite exposure to CDV and CPV.

  12. Seasonal selection of soil types and grass swards by roan antelope in a South African savanna.

    NARCIS (Netherlands)

    Heitkönig, I.M.A.; Owen-Smith, N.

    1997-01-01

    Roan antelope are distributed mainly in regions characterized by infertile soils, offering food of low quality. We hypothesized that roan may select localities with higher soil nutrient levels and/or grass swards with more favourable properties in terms of food abundance or quality than generally

  13. 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.

  14. The applicability of fair selection models in the South African context

    Directory of Open Access Journals (Sweden)

    G. K. Huysamen

    1995-06-01

    Full Text Available This article reviews several models that are aimed at achieving fair selection in situations in which underrepresented groups tend to obtain lower scores on selection tests. Whereas predictive bias is a statistical concept that refers to systematic errors in the prediction of individuals' criterion scores, selection fairness pertains to the extent to which selection results meet certain socio-political demands. The regression and equal-risk models adjust for differences in the criterion-on-test regression lines of different groups. The constant ratio, conditional probability and equal probability models manipulate the test cutoff scores of different groups so that certain ratios formed between different selection outcomes (correct acceptances, correct rejections, incorrect acceptances, incorrect rejections are the same for such groups. The decision-theoretic approach requires that utilities be attached to these different outcomes for different groups. These procedures are not only eminently suited to accommodate calls for affirmative action, but they also serve the cause of transparency. Opsomming Hierdie artikel verskaf 'n oorsig van verskeie modelle om billike keuring te verkry in situasies waar onderverteen-woordigende groepe geneig is om swakker op keuringstoetse te vaar. Terwyl voorspellingsydigheid 'n statistiese begrip is wat betrekking het op stelselmatige foute in die voorspelling van individue se kriteriumtellings, het keuringsbillikheid te make met die mate waarin keuringsresultate aan sekere sosiaal-politieke vereistes voldoen. Die regressieen gelyke-risiko-modelle maak aanpassings vir verskille in die kriterium-op-toetsregressielyne van verskillende groepe. Die konstante-verhoudings, voorwaardelike-waarskynlikheids- en gelyke-waarskynlikheidsmodelle manipuleer die toetsafkappunte van verskillende groepe sodat sekere verhoudings wat tussen keuringsresultate (korrekte aanvaardings, verkeerde aanvaardings, korrekte verwerpings

  15. Zinc or multiple micronutrient supplementation to reduce diarrhea and respiratory disease in South African children: a randomized controlled trial.

    Directory of Open Access Journals (Sweden)

    Kany-Kany Angelique Luabeya

    2007-06-01

    Full Text Available Prophylactic zinc supplementation has been shown to reduce diarrhea and respiratory illness in children in many developing countries, but its efficacy in children in Africa is uncertain.To determine if zinc, or zinc plus multiple micronutrients, reduces diarrhea and respiratory disease prevalence.Randomized, double-blind, controlled trial.Rural community in South Africa.THREE COHORTS: 32 HIV-infected children; 154 HIV-uninfected children born to HIV-infected mothers; and 187 HIV-uninfected children born to HIV-uninfected mothers.Children received either 1250 IU of vitamin A; vitamin A and 10 mg of zinc; or vitamin A, zinc, vitamins B1, B2, B6, B12, C, D, E, and K and copper, iodine, iron, and niacin starting at 6 months and continuing to 24 months of age. Homes were visited weekly.Primary outcome was percentage of days of diarrhea per child by study arm within each of the three cohorts. Secondary outcomes were prevalence of upper respiratory symptoms and percentage of children who ever had pneumonia by maternal report, or confirmed by the field worker.Among HIV-uninfected children born to HIV-infected mothers, median percentage of days with diarrhea was 2.3% for 49 children allocated to vitamin A; 2.5% in 47 children allocated to receive vitamin A and zinc; and 2.2% for 46 children allocated to multiple micronutrients (P = 0.852. Among HIV-uninfected children born to HIV-uninfected mothers, median percentage of days of diarrhea was 2.4% in 56 children in the vitamin A group; 1.8% in 57 children in the vitamin A and zinc group; and 2.7% in 52 children in the multiple micronutrient group (P = 0.857. Only 32 HIV-infected children were enrolled, and there were no differences between treatment arms in the prevalence of diarrhea. The prevalence of upper respiratory symptoms or incidence of pneumonia did not differ by treatment arms in any of the cohorts.When compared with vitamin A alone, supplementation with zinc, or with zinc and multiple

  16. Exploring factors contributing to voluntarily withdrawal by candidates during South African operational forces selection

    CSIR Research Space (South Africa)

    Van Heerden, A

    2016-11-01

    Full Text Available that take the decision to voluntarily withdraw from pre-selection training and of those that fail. 3. Methods A concurrent mixed method research approach was followed, which combines qualitative and quantitative research (Creswell, 2003, Creswell & Plano...-Clark, 2011). We simultaneously acquired qualitative and quantitative data through written responses to open-ended survey questions. Our research method was in line with the definition of Johnson et al. (2007: 123), “mixed methods research is the type...

  17. Control group selection in critical care randomized controlled trials evaluating interventional strategies: An ethical assessment.

    Science.gov (United States)

    Silverman, Henry J; Miller, Franklin G

    2004-03-01

    Ethical concern has been raised with critical care randomized controlled trials in which the standard of care reflects a broad range of clinical practices. Commentators have argued that trials without an unrestricted control group, in which standard practices are implemented at the discretion of the attending physician, lack the ability to redefine the standard of care and might expose subjects to excessive harms due to an inability to stop early. To develop a framework for analyzing control group selection for critical care trials. Ethical analysis. A key ethical variable in trial design is the extent with which the control group adequately reflects standard care practices. Such a control group might incorporate either the "unrestricted" practices of physicians or a protocol that specifies and restricts the parameters of standard practices. Control group selection should be determined with respect to the following ethical objectives of trial design: 1) clinical value, 2) scientific validity, 3) efficiency and feasibility, and 4) protection of human subjects. Because these objectives may conflict, control group selection will involve trade-offs and compromises. Trials using a protocolized rather than an unrestricted standard care control group will likely have enhanced validity. However, if the protocolized control group lacks representativeness to standard care practices, then trials that use such groups will offer less clinical value and could provide less assurance of protecting subjects compared with trials that use unrestricted control groups. For trials evaluating contrasting strategies that do not adequately represent standard practices, use of a third group that is more representative of standard practices will enhance clinical value and increase the ability to stop early if needed to protect subjects. These advantages might come at the expense of efficiency and feasibility. Weighing and balancing the competing ethical objectives of trial design should be

  18. Effectiveness of transcendental meditation on functional capacity and quality of life of African Americans with congestive heart failure: a randomized control study.

    Science.gov (United States)

    Jayadevappa, Ravishankar; Johnson, Jerry C; Bloom, Bernard S; Nidich, Sanford; Desai, Shashank; Chhatre, Sumedha; Raziano, Donna B; Schneider, Robert

    2007-01-01

    To evaluate the effectiveness of a Transcendental Meditation (TM) stress reduction program for African Americans with congestive heart failure (CHF). Randomized, controlled study We recruited 23 African American patients > or = 55 years of age who were recently hospitalized with New York Heart Association class II or III CHF and with an ejection fraction of Depression Scale (CES-D), rehospitalizations, brain natriuretic peptide, and cortisol. Changes in outcomes from baseline to three and six months after treatment were analyzed by using repeated measures analysis of variance, covarying for baseline score. For the primary outcome of functional capacity, the TM group significantly improved on the six-minute walk test from baseline to six months after treatment compared to the HE group (P = .034). On the secondary outcome measures, the TM group showed improvements in SF-36 subscales and total score on the Minnesota Living with Heart Failure scale. On the CES-D, the TM group showed significant decrease from baseline to six months compared to the HE group (P = .03). Also, the TM group had fewer rehospitalizations during the six months of followup. Results indicate that TM can be effective in improving the quality of life and functional capacity of African American CHF patients. Further validation of outcomes is planned via a large, multicenter trial with long-term follow-up.

  19. Unity in diversity: results of a randomized clinical culturally tailored pilot HIV prevention intervention trial in Baltimore, Maryland, for African American men who have sex with men.

    Science.gov (United States)

    Tobin, Karin; Kuramoto, Satoko J; German, Danielle; Fields, Errol; Spikes, Pilgrim S; Patterson, Jocelyn; Latkin, Carl

    2013-06-01

    Unity in Diversity was a randomized controlled trial of a culturally tailored HIV prevention intervention for African American men who have sex with men. The intervention condition was six group-based sessions and one individual session. The control condition was a single-session HIV prevention review. Participants were aged 18 years or older, identified as African American/Black race, reported having at least two sex partners in the prior 90 days (at least one of whom must be a male partner), unprotected anal sex with male partner in the prior 90 days, and willing to test for HIV. Retention exceeded 95% at 3-month follow-up. Results of multivariate logistic regression analysis adjusting for baseline risk, HIV status, and health insurance indicate intervention efficacy in decreasing the number of male sex partners and marginal effects on condom use with male partners and HIV-negative/unknown partners. Specifically, intervention condition was associated with increased odds of zero male sex partners (adjusted odds ratio [AOR] = 3.03, 95% confidence interval [CI] = 1.26-7.28), condom use with male partners (AOR = 2.64, 95% CI = 0.95-7.36), and HIV-negative/unknown status partners (AOR = 3.19, 95% CI = 0.98-10.38) at follow-up. These results contribute to the limited number of culturally appropriate models of HIV prevention intervention that are urgently needed for African American men who have sex with men to address their persistently high rates of HIV.

  20. In Pursuit of the African PhD: A Critical Survey of Emergent Policy Issues in Select Sub-Saharan African Nations, Ethiopia, Ghana and South Africa

    Science.gov (United States)

    Molla, Tebeje; Cuthbert, Denise

    2016-01-01

    After decades of decline, African higher education is now arguably in a new era of revival. With the prevalence of knowledge economy discourse, national governments in Africa and their development partners have increasingly aligned higher education with poverty reduction plans and strategies. Research capacity has become a critical development…

  1. The adverse effect of selective cyclooxygenase-2 inhibitor on random skin flap survival in rats.

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    Haiyong Ren

    Full Text Available BACKGROUND: Cyclooxygenase-2(COX-2 inhibitors provide desired analgesic effects after injury or surgery, but evidences suggested they also attenuate wound healing. The study is to investigate the effect of COX-2 inhibitor on random skin flap survival. METHODS: The McFarlane flap model was established in 40 rats and evaluated within two groups, each group gave the same volume of Parecoxib and saline injection for 7 days. The necrotic area of the flap was measured, the specimens of the flap were stained with haematoxylin-eosin(HE for histologic analysis. Immunohistochemical staining was performed to analyse the level of VEGF and COX-2 . RESULTS: 7 days after operation, the flap necrotic area ratio in study group (66.65 ± 2.81% was significantly enlarged than that of the control group(48.81 ± 2.33%(P <0.01. Histological analysis demonstrated angiogenesis with mean vessel density per mm(2 being lower in study group (15.4 ± 4.4 than in control group (27.2 ± 4.1 (P <0.05. To evaluate the expression of COX-2 and VEGF protein in the intermediate area II in the two groups by immunohistochemistry test .The expression of COX-2 in study group was (1022.45 ± 153.1, and in control group was (2638.05 ± 132.2 (P <0.01. The expression of VEGF in the study and control groups were (2779.45 ± 472.0 vs (4938.05 ± 123.6(P <0.01.In the COX-2 inhibitor group, the expressions of COX-2 and VEGF protein were remarkably down-regulated as compared with the control group. CONCLUSION: Selective COX-2 inhibitor had adverse effect on random skin flap survival. Suppression of neovascularization induced by low level of VEGF was supposed to be the biological mechanism.

  2. Phosphate Sorption Characteristics and External P Requirements of Selected South African Soils

    Directory of Open Access Journals (Sweden)

    E. M. Gichangi

    2008-10-01

    Full Text Available The Transkei is the largest consolidated area in South Africa where land is held by smallholder farmers but little is known about the extent of phosphate fixation in the region. This study was conducted to determine the phosphate sorption properties and external P requirements (EPR of selected soils from the Transkei region, South Africa and to relate derived sorption values to selected soil parameters. The P sorption maxima and EPR values varied widely ranging from 192.3 to 909.1 mg P kg−1 and from 2 to 123 mg P kg−1−1 soil, respectively. Citrate dithionite bicarbonate-extractable aluminum explained most of the observed variations in P sorption. About 43% of the soils were found to be moderate P fixers and may need management interventions to ensure adequate P availability to crops. The single point sorption index accurately predicted the EPR of the soils obviating the need to use multiple point sorption isotherms. The results suggested that the use of blanket phosphate fertilizer recommendations may not be a good strategy for the region as it may lead to under-application or over-application of P in some areas.

  3. Rapid selection of accessible and cleavable sites in RNA by Escherichia coli RNase P and random external guide sequences

    OpenAIRE

    Lundblad, Eirik W.; Xiao, Gaoping; Ko, Jae-hyeong; Altman, Sidney

    2008-01-01

    A method of inhibiting the expression of particular genes by using external guide sequences (EGSs) has been improved in its rapidity and specificity. Random EGSs that have 14-nt random sequences are used in the selection procedure for an EGS that attacks the mRNA for a gene in a particular location. A mixture of the random EGSs, the particular target RNA, and RNase P is used in the diagnostic procedure, which, after completion, is analyzed in a gel with suitable control lanes. Within a few ho...

  4. Age-related Cataract in a Randomized Trial of Selenium and Vitamin E in Men: The SELECT Eye Endpoints (SEE) Study

    Science.gov (United States)

    Christen, William G.; Glynn, Robert J.; Gaziano, J. Michael; Darke, Amy K.; Crowley, John J.; Goodman, Phyllis J.; Lippman, Scott M.; Lad, Thomas E.; Bearden, James D.; Goodman, Gary E.; Minasian, Lori M.; Thompson, Ian M.; Blanke, Charles D.; Klein, Eric A.

    2014-01-01

    Importance Observational studies suggest a role for dietary nutrients such as vitamin E and selenium in cataract prevention. However, the results of randomized trials of vitamin E supplements and cataract have been disappointing, and are not yet available for selenium. Objective To test whether long-term supplementation with selenium and vitamin E affects the incidence of cataract in a large cohort of men. Design, Setting, and Participants The SELECT Eye Endpoints (SEE) study was an ancillary study of the SWOG-coordinated Selenium and Vitamin E Cancer Prevention Trial (SELECT), a randomized, placebo-controlled, four arm trial of selenium and vitamin E conducted among 35,533 men aged 50 years and older for African Americans and 55 and older for all other men, at 427 participating sites in the US, Canada, and Puerto Rico. A total of 11,267 SELECT participants from 128 SELECT sites participated in the SEE ancillary study. Intervention Individual supplements of selenium (200 µg/d from L-selenomethionine) and vitamin E (400 IU/d of all rac-α-tocopheryl acetate). Main Outcome Measures Incident cataract, defined as a lens opacity, age-related in origin, responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-report confirmed by medical record review, and cataract extraction, defined as the surgical removal of an incident cataract. Results During a mean (SD) of 5.6 (1.2) years of treatment and follow-up, 389 cases of cataract were documented. There were 185 cataracts in the selenium group and 204 in the no selenium group (hazard ratio [HR], 0.91; 95 percent confidence interval [CI], 0.75 to 1.11; P=.37). For vitamin E, there were 197 cases in the treated group and 192 in the placebo group (HR, 1.02; CI, 0.84 to 1.25; P=.81). Similar results were observed for cataract extraction. Conclusions and Relevance These randomized trial data from a large cohort of apparently healthy men indicate that long-term daily supplementation with selenium

  5. 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

    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.......7%; specificity = 70.8%; positive predictive value = 62.2%; negative predictive value = 82.9%). CONCLUSIONS: Random blood glucose could possibly be used to assess glycaemic control among patients with type 2 DM in rural settings of sub-Saharan Africa....... 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...

  6. Selective habitat utilisation and impact on vegetation by African elephant within a heterogeneous landscape

    Directory of Open Access Journals (Sweden)

    A. Steyn

    2001-07-01

    Full Text Available Since 1992, a total of 33 elephants have been reintroduced to a 31 000 ha game-fenced section of the Songimvelo Game Reserve in the Barberton Mountainland, South Africa. The impact from elephant was assessed on the attainment of the primary management objectives which are the conservation of plant community and plant species diversity. A total of 160 semi-quantitative plots were systematically sampled along foraging paths. Vegetation was assessed in terms of dominant species composition and species utilised. Elephant activity is mostly confined to a rugged 1 200 ha portion of the reserve. Forest, thickets and woodlands are positively selected, whereas shrublands and grasslands are little utilised. A total of 73 woody species were recorded within the sample plots. Thirtynine of these species were utilised in the woodlands, 31 in the forest and thickets, and only 18 in the shrublands. Acacia ataxacantha, Dalbergia armata and Acacia caffra are ranked highest in dominance and in utilisation values. In contrast, Cussonia spicata and Pterocarpus angolensis are less common but are much selected. Continued utilisation at present levels could significantly threaten their persistence. These preliminary results indicate that the present low overall density of elephants relative to many other conservation areas already has a marked effect on certain plant species. Absolute elephant density figures are relatively meaningless within a heterogeneous landscape. The specific community and species make-up of the landscape needs to be taken into account for the determination of bounds to elephant numbers in order to ensure the maintenance of present plant species diversity levels.

  7. Weight loss and improved metabolic outcomes amongst rural African American women in the Deep South: six-month outcomes from a community-based randomized trial.

    Science.gov (United States)

    Ard, J D; Carson, T L; Shikany, J M; Li, Y; Hardy, C M; Robinson, J C; Williams, A G; Baskin, M L

    2017-07-01

    Obesity is highly prevalent in African American women, especially those in the rural southern USA, resulting in persistent health disparities. To test the effectiveness of an evidence-based behavioural weight loss intervention delivered by community health advisors to African American women in the rural south. Overweight or obese African American women (30-70 years) from eight counties in Mississippi and Alabama participated in a 24-month randomized controlled trial of an evidence-based behavioural weight loss programme augmented with community strategies to support healthy lifestyles (Weight Loss Plus, N = 154) compared to the weight loss programme alone (Weight Loss Only, N = 255). This study reports on 6-month outcomes on primary (weight change) and secondary (waist circumference, blood pressure, lipids, fasting blood glucose) outcomes, coinciding with the completion of the intensive weight loss phase. Weight Loss Only participants lost an average of 2.2 kg (P Weight Loss Plus participants lost an average of 3.2 kg (P lost at least 5% of their body weight was 27.1% with no difference between treatment groups. Similarly, we observed statistically significant reductions in blood pressure, waist circumference and triglycerides in each treatment group, with no statistical differences between groups. Trained lay health staff and volunteers from the rural southern USA were able to deliver a translation of a high-intensity behavioural intervention targeted to African American women, resulting in clinically meaningful weight loss and improvement in other metabolic outcomes in a significant proportion of participants. © 2017 The Association for the Publication of the Journal of Internal Medicine.

  8. Randomized controlled trial of the effects of nurse case manager and community health worker interventions on risk factors for diabetes-related complications in urban African Americans.

    Science.gov (United States)

    Gary, Tiffany L; Bone, Lee R; Hill, Martha N; Levine, David M; McGuire, Maura; Saudek, Christopher; Brancati, Frederick L

    2003-07-01

    African Americans suffer disproportionately from diabetes complications, but little research has focused on how to improve diabetic control in this population. There are also few or no data on a combined primary care and community-based intervention approach. We randomly assigned 186 urban African Americans with type 2 diabetes (76% female, mean A SD age 59 A 9 years) to 1 of 4 parallel arms: (1) usual care only; (2) usual care + nurse case manager (NCM); (3) usual care + community health worker (CHW); (4) usual care + nurse case manager/community health worker team. Using the framework of the Precede-Proceed behavioral model, interventions included patient counseling regarding self-care practices and physician reminders. The 2-year follow-up visit was completed by 149 individuals (84%). Compared to the Usual care group, the NCM group and the CHW group had modest declines in HbA(1c) over 2 years (0.3 and 0.3%, respectively), and the combined NCM/CHW group had a greater decline in HbA(1c) (0.8%. P = 0.137). After adjustment for baseline differences and/or follow-up time, the combined NCM/CHW group showed improvements in triglycerides (-35.5 mg/dl; P = 0.041) and diastolic blood pressure, compared to the usual care group (-5.6 mmHg; P = 0.042). Combined NCM/CHW interventions may improve diabetic control in urban African Americans with type 2 diabetes. Although results were clinically important, they did not reach statistical significance. This approach deserves further attention as a means to reduce the excess risk of diabetic complications in African Americans.

  9. Seasonal habitat selection by African buffalo Syncerus caffer in the Savuti–Mababe–Linyanti ecosystem of northern Botswana

    Directory of Open Access Journals (Sweden)

    Keoikantse Sianga

    2017-05-01

    Full Text Available This study aimed to establish seasonal movement and habitat selection patterns of African buffalo Syncerus caffer in relation to a detailed habitat map and according to seasonal changes in forage quality and quantity in the Savuti–Mababe–Linyanti ecosystem (Botswana. Two buffalo were collared in November 2011 and another in October 2012. All three buffalo had greater activities in the mopane–sandveld woodland mosaic during the wet season, which provided high-quality leafy grasses and ephemeral water for drinking, but moved to permanent water and reliable forage of various wetlands (swamps and floodplains and riverine woodlands during the dry season. Wetlands had higher grass greenness, height and biomass than woodlands during the dry season. Buffalo had similar wet season concentration areas in the 2011–2012 and 2012–2013 wet seasons and similar dry season concentration areas over the 2012 and 2013 dry seasons. However, their dry season location of collaring in 2011 differed dramatically from their 2012 and 2013 dry season concentration areas, possibly because of the exceptionally high flood levels in 2011, which reduced accessibility to their usual dry season concentration areas. The study demonstrates that extremely large and heterogeneous landscapes are needed to conserve buffalo in sandy, dystrophic ecosystems with variable rainfall.Conservation implications: This study emphasises the importance of large spatial scale available for movement, which enables adaptation to changing conditions between years and seasons.

  10. Fuzzy logic and adaptive neuro-fuzzy inference system for characterization of contaminant exposure through selected biomarkers in African catfish.

    Science.gov (United States)

    Karami, Ali; Keiter, Steffen; Hollert, Henner; Courtenay, Simon C

    2013-03-01

    This study represents a first attempt at applying a fuzzy inference system (FIS) and an adaptive neuro-fuzzy inference system (ANFIS) to the field of aquatic biomonitoring for classification of the dosage and time of benzo[a]pyrene (BaP) injection through selected biomarkers in African catfish (Clarias gariepinus). Fish were injected either intramuscularly (i.m.) or intraperitoneally (i.p.) with BaP. Hepatic glutathione S-transferase (GST) activities, relative visceral fat weights (LSI), and four biliary fluorescent aromatic compounds (FACs) concentrations were used as the inputs in the modeling study. Contradictory rules in FIS and ANFIS models appeared after conversion of bioassay results into human language (rule-based system). A "data trimming" approach was proposed to eliminate the conflicts prior to fuzzification. However, the model produced was relevant only to relatively low exposures to BaP, especially through the i.m. route of exposure. Furthermore, sensitivity analysis was unable to raise the classification rate to an acceptable level. In conclusion, FIS and ANFIS models have limited applications in the field of fish biomarker studies.

  11. The predictive validity of the selection battery used for junior leader training within the South African national defence force

    Directory of Open Access Journals (Sweden)

    Johannes Muller

    2003-10-01

    Full Text Available The principal objective of the study was to determine the predictive validity of the test battery used for the selection of junior leaders in the South African National Defence Force. A sample of 96 respondents completed certain indices of the SPEEX-Battery as well as the Advanced Ravens Progressive Matrices test. The test results were compared with the course results. Using canonical correlation analysis, a highly significant relationship was found between the independent variables and the dependent variables (r = 0,787; p is less than 0,00005. The predictors with the highest loadings were cognitive ability, conceptualisation, reading comprehension, listening potential, physical stress, and mental stress. Opsomming Die hoofdoelwit van die studie was om die voorspellingsgeldigheid van die toetsbattery vir keuring van junior leiers in die Suid Afrikaanse Nasionale Weermag te evalueer. ’n Steekproef van 96 respondente het sekere indekse van die SPEEX-Battery asook die Advanced Ravens Progressive Matrices toets voltooi. Die toetsresultate is vervolgens vergelyk met die kursusuitslae. Die veranderlikes is aan kanoniese korrelasie-ontleding onderwerp wat ’n betekenisvolle verwantskap opgelewer het tussen die onafhanklike veranderlikes en die afhanklike veranderlikes (r = 0,787; p is kleiner as 0,00005. Die voorspellers met die hoogste ladings was kognitiewe vermoë, konseptualisering, leesbegrip, luisterpotensiaal, fisieke stres en psigiese stres.

  12. Random genetic drift, natural selection, and noise in human cranial evolution.

    Science.gov (United States)

    Roseman, Charles C

    2016-08-01

    This study assesses the extent to which relationships among groups complicate comparative studies of adaptation in recent human cranial variation and the extent to which departures from neutral additive models of evolution hinder the reconstruction of population relationships among groups using cranial morphology. Using a maximum likelihood evolutionary model fitting approach and a mixed population genomic and cranial data set, I evaluate the relative fits of several widely used models of human cranial evolution. Moreover, I compare the goodness of fit of models of cranial evolution constrained by genomic variation to test hypotheses about population specific departures from neutrality. Models from population genomics are much better fits to cranial variation than are traditional models from comparative human biology. There is not enough evolutionary information in the cranium to reconstruct much of recent human evolution but the influence of population history on cranial variation is strong enough to cause comparative studies of adaptation serious difficulties. Deviations from a model of random genetic drift along a tree-like population history show the importance of environmental effects, gene flow, and/or natural selection on human cranial variation. Moreover, there is a strong signal of the effect of natural selection or an environmental factor on a group of humans from Siberia. The evolution of the human cranium is complex and no one evolutionary process has prevailed at the expense of all others. A holistic unification of phenome, genome, and environmental context, gives us a strong point of purchase on these problems, which is unavailable to any one traditional approach alone. Am J Phys Anthropol 160:582-592, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  13. CURE-SMOTE algorithm and hybrid algorithm for feature selection and parameter optimization based on random forests.

    Science.gov (United States)

    Ma, Li; Fan, Suohai

    2017-03-14

    The random forests algorithm is a type of classifier with prominent universality, a wide application range, and robustness for avoiding overfitting. But there are still some drawbacks to random forests. Therefore, to improve the performance of random forests, this paper seeks to improve imbalanced data processing, feature selection and parameter optimization. We propose the CURE-SMOTE algorithm for the imbalanced data classification problem. Experiments on imbalanced UCI data reveal that the combination of Clustering Using Representatives (CURE) enhances the original synthetic minority oversampling technique (SMOTE) algorithms effectively compared with the classification results on the original data using random sampling, Borderline-SMOTE1, safe-level SMOTE, C-SMOTE, and k-means-SMOTE. Additionally, the hybrid RF (random forests) algorithm has been proposed for feature selection and parameter optimization, which uses the minimum out of bag (OOB) data error as its objective function. Simulation results on binary and higher-dimensional data indicate that the proposed hybrid RF algorithms, hybrid genetic-random forests algorithm, hybrid particle swarm-random forests algorithm and hybrid fish swarm-random forests algorithm can achieve the minimum OOB error and show the best generalization ability. The training set produced from the proposed CURE-SMOTE algorithm is closer to the original data distribution because it contains minimal noise. Thus, better classification results are produced from this feasible and effective algorithm. Moreover, the hybrid algorithm's F-value, G-mean, AUC and OOB scores demonstrate that they surpass the performance of the original RF algorithm. Hence, this hybrid algorithm provides a new way to perform feature selection and parameter optimization.

  14. Noise-induced hearing loss in randomly selected New York dairy farmers.

    Science.gov (United States)

    May, J J; Marvel, M; Regan, M; Marvel, L H; Pratt, D S

    1990-01-01

    To understand better the effects of noise levels associated with dairy farming, we randomly selected 49 full-time dairy farmers from an established cohort. Medical and occupational histories were taken and standard audiometric testing was done. Forty-six males (94%) and three females (6%) with a mean age of 43.5 (+/- 13) years and an average of 29.4 (+/- 14) years in farming were tested. Pure Tone Average thresholds (PTA4) at 0.5, 1.0, 2.0, and 3.0 kHz plus High Frequency Average thresholds (HFA3) at 3.0, 4.0, and 6.0 kHz were calculated. Subjects with a loss of greater than or equal to 20 db in either ear were considered abnormal. Eighteen subjects (37%) had abnormal PTA4S and 32 (65%) abnormal HFA3S. The left ear was more severely affected in both groups (p less than or equal to .05, t-test). Significant associations were found between hearing loss and years worked (odds ratio 4.1, r = .53) and age (odds ratio 4.1, r = .59). No association could be found between hearing loss and measles; mumps; previous ear infections; or use of power tools, guns, motorcycles, snowmobiles, or stereo headphones. Our data suggest that among farmers, substantial hearing loss occurs especially in the high-frequency ranges. Presbycusis is an important confounding variable.

  15. Modeling Slotted Aloha as a Stochastic Game with Random Discrete Power Selection Algorithms

    Directory of Open Access Journals (Sweden)

    Rachid El-Azouzi

    2009-01-01

    Full Text Available We consider the uplink case of a cellular system where bufferless mobiles transmit over a common channel to a base station, using the slotted aloha medium access protocol. We study the performance of this system under several power differentiation schemes. Indeed, we consider a random set of selectable transmission powers and further study the impact of priorities given either to new arrival packets or to the backlogged ones. Later, we address a general capture model where a mobile transmits successfully a packet if its instantaneous SINR (signal to interferences plus noise ratio is lager than some fixed threshold. Under this capture model, we analyze both the cooperative team in which a common goal is jointly optimized as well as the noncooperative game problem where mobiles reach to optimize their own objectives. Furthermore, we derive the throughput and the expected delay and use them as the objectives to optimize and provide a stability analysis as alternative study. Exhaustive performance evaluations were carried out, we show that schemes with power differentiation improve significantly the individual as well as global performances, and could eliminate in some cases the bi-stable nature of slotted aloha.

  16. Anti-inflammatory and antibacterial profiles of selected compounds found in South African propolis

    Directory of Open Access Journals (Sweden)

    S. Buthelezi

    2010-02-01

    Full Text Available Propolis is a complex resinous substance manufactured by honey bees to scaffold and protect the hive against pathogens. Although it has been widely used for its medicinal properties, it is unknown whether the activity depends on the concentrations of specific constituents or on potentiation between these. This study describes (1 the individual topical anti-inflammatory activities of selected flavonoids commonly found in propolis, and (2 their antibacterial activities, alone or in combination with the non-flavonoid caffeic acid phenethyl ester (CAPE. For the anti-inflammatory activities, the reduction in croton oil-induced oedema in a mouse model, after topical application of quercetin and galangin for 3 h, was more than 50%, while after 6 h of treatment the reduction was less then 50%. By contrast, the suppressive activity of luteolin was about 30% and 50%, for treatments of 3 h and 6 h, respectively. The maximum inhibition of the growth of Staphylococcus aureus by each of CAPE, eriodictyol and quercetin was about 20%, while luteolin was inactive. When combined with CAPE, potentiation of the antibacterial effect was observed in the case of luteolin, but antagonism was observed when combined with either eriodictyol or quercetin. The propolis flavonoids each appear to have significant anti-inflammatory activity while their antibacterial activities are somewhat weaker and significant only when luteolin was combined with CAPE.

  17. Individual- and area-level unemployment influence smoking cessation among African Americans participating in a randomized clinical trial.

    Science.gov (United States)

    Kendzor, Darla E; Reitzel, Lorraine R; Mazas, Carlos A; Cofta-Woerpel, Ludmila M; Cao, Yumei; Ji, Lingyun; Costello, Tracy J; Vidrine, Jennifer Irvin; Businelle, Michael S; Li, Yisheng; Castro, Yessenia; Ahluwalia, Jasjit S; Cinciripini, Paul M; Wetter, David W

    2012-05-01

    African Americans suffer disproportionately from the adverse health consequences of smoking, and also report substantially lower socioeconomic status than Whites and other racial/ethnic groups in the U.S. Although socioeconomic disadvantage is known to have a negative influence on smoking cessation rates and overall health, little is known about the influence of socioeconomic status on smoking cessation specifically among African Americans. Thus, the purpose of the current study was to characterize the impact of several individual- and area-level indicators of socioeconomic status on smoking cessation among African Americans. Data were collected as part of a smoking cessation intervention study for African American smokers (N = 379) recruited from the Houston, Texas, metropolitan area, who participated in the study between 2005 and 2007. The separate and combined influences of individual-level (insurance status, unemployment, education, and income) and area-level (neighborhood unemployment, education, income, and poverty) indicators of socioeconomic status on continuous smoking abstinence were examined across time intervals using continuation ratio logit modeling. Individual-level analyses indicated that unemployment was significantly associated with reduced odds of smoking abstinence, while higher income was associated with greater odds of abstinence. However, only unemployment remained a significant predictor of abstinence when unemployment and income were included in the model together. Area-level analyses indicated that greater neighborhood unemployment and poverty were associated with reduced odds of smoking abstinence, while greater neighborhood education was associated with higher odds of abstinence. However, only neighborhood unemployment remained significantly associated with abstinence status when individual-level income and unemployment were included in the model. Overall, findings suggest that individual- and area-level unemployment have a negative

  18. The prevalence of symptoms associated with pulmonary tuberculosis in randomly selected children from a high burden community

    OpenAIRE

    Marais, B.; Obihara, C; Gie, R.; Schaaf, H; Hesseling, A.; Lombard, C.; Enarson, D; Bateman, E; Beyers, N

    2005-01-01

    Background: Diagnosis of childhood tuberculosis is problematic and symptom based diagnostic approaches are often promoted in high burden settings. This study aimed (i) to document the prevalence of symptoms associated with tuberculosis among randomly selected children living in a high burden community, and (ii) to compare the prevalence of these symptoms in children without tuberculosis to those in children with newly diagnosed tuberculosis.

  19. Whole-genome sequence analyses of Western Central African Pygmy hunter-gatherers reveal a complex demographic history and identify candidate genes under positive natural selection.

    Science.gov (United States)

    Hsieh, PingHsun; Veeramah, Krishna R; Lachance, Joseph; Tishkoff, Sarah A; Wall, Jeffrey D; Hammer, Michael F; Gutenkunst, Ryan N

    2016-03-01

    African Pygmies practicing a mobile hunter-gatherer lifestyle are phenotypically and genetically diverged from other anatomically modern humans, and they likely experienced strong selective pressures due to their unique lifestyle in the Central African rainforest. To identify genomic targets of adaptation, we sequenced the genomes of four Biaka Pygmies from the Central African Republic and jointly analyzed these data with the genome sequences of three Baka Pygmies from Cameroon and nine Yoruba famers. To account for the complex demographic history of these populations that includes both isolation and gene flow, we fit models using the joint allele frequency spectrum and validated them using independent approaches. Our two best-fit models both suggest ancient divergence between the ancestors of the farmers and Pygmies, 90,000 or 150,000 yr ago. We also find that bidirectional asymmetric gene flow is statistically better supported than a single pulse of unidirectional gene flow from farmers to Pygmies, as previously suggested. We then applied complementary statistics to scan the genome for evidence of selective sweeps and polygenic selection. We found that conventional statistical outlier approaches were biased toward identifying candidates in regions of high mutation or low recombination rate. To avoid this bias, we assigned P-values for candidates using whole-genome simulations incorporating demography and variation in both recombination and mutation rates. We found that genes and gene sets involved in muscle development, bone synthesis, immunity, reproduction, cell signaling and development, and energy metabolism are likely to be targets of positive natural selection in Western African Pygmies or their recent ancestors. © 2016 Hsieh et al.; Published by Cold Spring Harbor Laboratory Press.

  20. Rapid selection of accessible and cleavable sites in RNA by Escherichia coli RNase P and random external guide sequences.

    Science.gov (United States)

    Lundblad, Eirik W; Xiao, Gaoping; Ko, Jae-Hyeong; Altman, Sidney

    2008-02-19

    A method of inhibiting the expression of particular genes by using external guide sequences (EGSs) has been improved in its rapidity and specificity. Random EGSs that have 14-nt random sequences are used in the selection procedure for an EGS that attacks the mRNA for a gene in a particular location. A mixture of the random EGSs, the particular target RNA, and RNase P is used in the diagnostic procedure, which, after completion, is analyzed in a gel with suitable control lanes. Within a few hours, the procedure is complete. The action of EGSs designed by an older method is compared with EGSs designed by the random EGS method on mRNAs from two bacterial pathogens.

  1. 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

  2. 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

  3. 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

  4. Bayesian dose selection design for a binary outcome using restricted response adaptive randomization.

    Science.gov (United States)

    Meinzer, Caitlyn; Martin, Renee; Suarez, Jose I

    2017-09-08

    In phase II trials, the most efficacious dose is usually not known. Moreover, given limited resources, it is difficult to robustly identify a dose while also testing for a signal of efficacy that would support a phase III trial. Recent designs have sought to be more efficient by exploring multiple doses through the use of adaptive strategies. However, the added flexibility may potentially increase the risk of making incorrect assumptions and reduce the total amount of information available across the dose range as a function of imbalanced sample size. To balance these challenges, a novel placebo-controlled design is presented in which a restricted Bayesian response adaptive randomization (RAR) is used to allocate a majority of subjects to the optimal dose of active drug, defined as the dose with the lowest probability of poor outcome. However, the allocation between subjects who receive active drug or placebo is held constant to retain the maximum possible power for a hypothesis test of overall efficacy comparing the optimal dose to placebo. The design properties and optimization of the design are presented in the context of a phase II trial for subarachnoid hemorrhage. For a fixed total sample size, a trade-off exists between the ability to select the optimal dose and the probability of rejecting the null hypothesis. This relationship is modified by the allocation ratio between active and control subjects, the choice of RAR algorithm, and the number of subjects allocated to an initial fixed allocation period. While a responsive RAR algorithm improves the ability to select the correct dose, there is an increased risk of assigning more subjects to a worse arm as a function of ephemeral trends in the data. A subarachnoid treatment trial is used to illustrate how this design can be customized for specific objectives and available data. Bayesian adaptive designs are a flexible approach to addressing multiple questions surrounding the optimal dose for treatment efficacy

  5. 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

  6. 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

  7. Generation of Aptamers from A Primer-Free Randomized ssDNA Library Using Magnetic-Assisted Rapid Aptamer Selection

    Science.gov (United States)

    Tsao, Shih-Ming; Lai, Ji-Ching; Horng, Horng-Er; Liu, Tu-Chen; Hong, Chin-Yih

    2017-04-01

    Aptamers are oligonucleotides that can bind to specific target molecules. Most aptamers are generated using random libraries in the standard systematic evolution of ligands by exponential enrichment (SELEX). Each random library contains oligonucleotides with a randomized central region and two fixed primer regions at both ends. The fixed primer regions are necessary for amplifying target-bound sequences by PCR. However, these extra-sequences may cause non-specific bindings, which potentially interfere with good binding for random sequences. The Magnetic-Assisted Rapid Aptamer Selection (MARAS) is a newly developed protocol for generating single-strand DNA aptamers. No repeat selection cycle is required in the protocol. This study proposes and demonstrates a method to isolate aptamers for C-reactive proteins (CRP) from a randomized ssDNA library containing no fixed sequences at 5‧ and 3‧ termini using the MARAS platform. Furthermore, the isolated primer-free aptamer was sequenced and binding affinity for CRP was analyzed. The specificity of the obtained aptamer was validated using blind serum samples. The result was consistent with monoclonal antibody-based nephelometry analysis, which indicated that a primer-free aptamer has high specificity toward targets. MARAS is a feasible platform for efficiently generating primer-free aptamers for clinical diagnoses.

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

    Science.gov (United States)

    Schoenthaler, Antoinette; Luerassi, Leanne; Teresi, Jeanne A; Silver, Stephanie; Kong, Jian; Odedosu, Taiye; Trilling, Samantha; Errico, Anna; Uvwo, Oshevire; Sebek, Kimberly; Adekoya, Adetutu; Ogedegbe, Gbenga

    2011-12-22

    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. 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. This vanguard trial will provide information on how to refine MINT-TLC and integrate it into a standard treatment protocol for hypertensive African Americans as a result of the data obtained; thus maximizing the

  9. Reproductive Health Knowledge among African American Women Enrolled in a Clinic-Based Randomized Controlled Trial to Reduce Psychosocial and Behavioral Risk: Project DC-HOPE.

    Science.gov (United States)

    Backonja, Uba; Robledo, Candace A; Wallace, Maeve E; Flores, Katrina F; Kiely, Michele

    2016-01-01

    Washington, DC, has among the highest rates of sexually transmitted infections and unintended pregnancy in the United States. Increasing women's reproductive health knowledge may help to address these reproductive health issues. This analysis assessed whether high-risk pregnant African American women in Washington, DC, who participated in an intervention to reduce behavioral and psychosocial risks had greater reproductive health knowledge than women receiving usual care. Project DC-HOPE was a randomized, controlled trial that included pregnant African American women in Washington, DC, recruited during prenatal care (PNC). Women in the intervention group were provided reproductive health education and received tailored counseling sessions to address their psychosocial and behavioral risk(s) (cigarette smoking, environmental tobacco smoke exposure, depression, and intimate partner violence). Women in the control group received usual PNC. Participants completed a 10-item reproductive knowledge assessment at baseline (n = 1,044) and postpartum (n = 830). Differences in total reproductive health knowledge scores at baseline and postpartum between groups were examined via χ(2) tests. Differences in postpartum mean total score by group were assessed via multiple linear regression. Women in both groups and at both time points scored approximately 50% on the knowledge assessments. At postpartum, women in the intervention group had higher total scores compared with women receiving usual care (mean 5.40 [SD 1.60] vs. 5.03 [SD 1.53] out of 10, respectively; p reproductive health knowledge, overall scores remained low. Development of interventions designed to impart accurate, individually tailored information to women may promote reproductive health knowledge among high-risk pregnant African American women residing in Washington, DC. Published by Elsevier Inc.

  10. 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

  11. 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, ...

  12. Fungi associated with african mudfish ( Clarias gariepinus , Burchell ...

    African Journals Online (AJOL)

    An investigation was conducted to determine the presence of fungi in C. gariepinus harvested from selected farms and dams in Zaria and its environs. A total of 360 randomly sampled Clarias gariepinus (African mudfish) and 144 fish holding water samples were collected from three dams (wild captured) and three fish farms ...

  13. 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.

  14. The basic science and mathematics of random mutation and natural selection.

    Science.gov (United States)

    Kleinman, Alan

    2014-12-20

    The mutation and natural selection phenomenon can and often does cause the failure of antimicrobial, herbicidal, pesticide and cancer treatments selection pressures. This phenomenon operates in a mathematically predictable behavior, which when understood leads to approaches to reduce and prevent the failure of the use of these selection pressures. The mathematical behavior of mutation and selection is derived using the principles given by probability theory. The derivation of the equations describing the mutation and selection phenomenon is carried out in the context of an empirical example. Copyright © 2014 John Wiley & Sons, Ltd.

  15. The effect of prenatal docosahexaenoic acid supplementation on infant outcomes in African American women living in low-income environments: A randomized, controlled trial.

    Science.gov (United States)

    Keenan, Kate; Hipwell, Alison; McAloon, Rose; Hoffmann, Amy; Mohanty, Arpita; Magee, Kelsey

    2016-09-01

    African American women living in urban, low-income environments are at high risk for poor nutrition during pregnancy and birth complications. To test the effectiveness of prenatal docosahexaenoic acid (DHA) supplementation on birth outcomes and infant development in a sample of African American women with Medicaid insurance and living in the city of Pittsburgh. The Nutrition and Pregnancy Study (NAPS) is a double-blind, randomized controlled trial of prenatal DHA supplementation conducted between 2012 and 2014. Participants were recruited from obstetric clinics at the University of Pittsburgh Medical Center. Sixty-four pregnant, African American women were enrolled at 16-21 weeks of gestation and randomized to either 450mg/day of DHA (22:6n-3)(n=43) or a soybean placebo (n=21). Four women (6.3%) withdrew from the study: two participants from each study arm; complete data were obtained for 49 infants (76.5%) at the 3-month assessment. Supplementation with DHA or placebo continued from the beginning of enrollment through delivery. Data on birth outcomes were collected from medical records. At approximately 3 months post-partum, mothers brought their infants to the laboratory where the Bayley Scales of Infant Development (BSID-III) were administered and cortisol response to the Face-to-Face Still-Face (FFSF) paradigm was assessed. Infants of mothers who received DHA supplementation had higher birth weight (3.174g versus 2.890g) than infants of mothers receiving placebo (F [2.40]=6.09, p=0.018, eta=0.36), and were more likely to have a 1-min Apgar score greater than 8 (OR=5.99 [95% CI=1.25-28.75], p=0.025). Infants of mothers who received DHA compared with infants of mothers receiving placebo had lower levels of cortisol in response to the FFSF paradigm (F [1.32]=5.36, p=0.018, eta=0.36). None of the scores on the BSID-III differed as a function of active supplement versus placebo. Infants of women living in urban, low-income environments who received DHA

  16. Text Messaging to Improve Hypertension Medication Adherence in African Americans From Primary Care and Emergency Department Settings: Results From Two Randomized Feasibility Studies.

    Science.gov (United States)

    Buis, Lorraine; Hirzel, Lindsey; Dawood, Rachelle M; Dawood, Katee L; Nichols, Lauren P; Artinian, Nancy T; Schwiebert, Loren; Yarandi, Hossein N; Roberson, Dana N; Plegue, Melissa A; Mango, LynnMarie C; Levy, Phillip D

    2017-02-01

    Hypertension (HTN) is an important problem in the United States, with an estimated 78 million Americans aged 20 years and older suffering from this condition. Health disparities related to HTN are common in the United States, with African Americans suffering from greater prevalence of the condition than whites, as well as greater severity, earlier onset, and more complications. Medication adherence is an important component of HTN management, but adherence is often poor, and simply forgetting to take medications is often cited as a reason. Mobile health (mHealth) strategies have the potential to be a low-cost and effective method for improving medication adherence that also has broad reach. Our goal was to determine the feasibility, acceptability, and preliminary clinical effectiveness of BPMED, an intervention designed to improve medication adherence among African Americans with uncontrolled HTN, through fully automated text messaging support. We conducted two parallel, unblinded randomized controlled pilot trials with African-American patients who had uncontrolled HTN, recruited from primary care and emergency department (ED) settings. In each trial, participants were randomized to receive either usual care or the BPMED intervention for one month. Data were collected in-person at baseline and one-month follow-up, assessing the effect on medication adherence, systolic and diastolic blood pressure (SBP and DBP), medication adherence self-efficacy, and participant satisfaction. Data for both randomized controlled pilot trials were analyzed separately and combined. A total of 58 primary care and 65 ED participants were recruited with retention rates of 91% (53/58) and 88% (57/65), respectively. BPMED participants consistently showed numerically greater, yet nonsignificant, improvements in measures of medication adherence (mean change 0.9, SD 2.0 vs mean change 0.5, SD 1.5, P=.26), SBP (mean change -12.6, SD 24.0 vs mean change -11.3, SD 25.5 mm Hg, P=.78), and DBP

  17. African Magazines for American Libraries

    Science.gov (United States)

    Berman, Sanford

    1970-01-01

    From the varied spectrum of African periodical publishing, a selection of particular interest - an annotated bibliography of English-language titles produced wholly (or mainly) by Africans in Africa. (Editor/JB)

  18. Novel random peptide libraries displayed on AAV serotype 9 for selection of endothelial cell-directed gene transfer vectors.

    Science.gov (United States)

    Varadi, K; Michelfelder, S; Korff, T; Hecker, M; Trepel, M; Katus, H A; Kleinschmidt, J A; Müller, O J

    2012-08-01

    We have demonstrated the potential of random peptide libraries displayed on adeno-associated virus (AAV)2 to select for AAV2 vectors with improved efficiency for cell type-directed gene transfer. AAV9, however, may have advantages over AAV2 because of a lower prevalence of neutralizing antibodies in humans and more efficient gene transfer in vivo. Here we provide evidence that random peptide libraries can be displayed on AAV9 and can be utilized to select for AAV9 capsids redirected to the cell type of interest. We generated an AAV9 peptide display library, which ensures that the displayed peptides correspond to the packaged genomes and performed four consecutive selection rounds on human coronary artery endothelial cells in vitro. This screening yielded AAV9 library capsids with distinct peptide motifs enabling up to 40-fold improved transduction efficiencies compared with wild-type (wt) AAV9 vectors. Incorporating sequences selected from AAV9 libraries into AAV2 capsids could not increase transduction as efficiently as in the AAV9 context. To analyze the potential on endothelial cells in the intact natural vascular context, human umbilical veins were incubated with the selected AAV in situ and endothelial cells were isolated. Fluorescence-activated cell sorting analysis revealed a 200-fold improved transduction efficiency compared with wt AAV9 vectors. Furthermore, AAV9 vectors with targeting sequences selected from AAV9 libraries revealed an increased transduction efficiency in the presence of human intravenous immunoglobulins, suggesting a reduced immunogenicity. We conclude that our novel AAV9 peptide library is functional and can be used to select for vectors for future preclinical and clinical gene transfer applications.

  19. 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

    2016-05-01

    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.

  20. Study on the structure and gasification characteristics of selected South African bituminous coal in fluidised bed gasification

    CSIR Research Space (South Africa)

    Oboirien, BO

    2009-10-01

    Full Text Available The gasification characteristics of three South African bituminous coals were investigated in a bubbling fluidised bed reactor. The three coals are similar in rank, but two are inertinite-rich coals and the third has high vitrinite content...

  1. Study on the structure and gasification characteristics of selected South African bituminous coals in fluidised bed gasification

    CSIR Research Space (South Africa)

    Oboirien, BO

    2011-04-01

    Full Text Available The gasification characteristics of three South African bituminous coals were investigated in a bubbling fluidised bed reactor. The three coals are similar in rank, but two are inertinite-rich coals and the third has a high vitrinite content...

  2. Why Educational Policies Can Fail: An Overview of Selected African Experiences. World Bank Discussion Papers 82. Africa Technical Department Series.

    Science.gov (United States)

    Psacharopoulos, George

    This paper reviews a number of educational policy statements in East African countries, on issues ranging from combining education with production at the primary level to the financing of higher education. An assessment is made as to how successful the policies have been in achieving their original intention. The paper's conclusion is that policy…

  3. Cultural Diversity: Resources for Music Educators in Selected Works of Three Contemporary African-American Classical Composers

    Science.gov (United States)

    Choi, Eunjung; Keith, Laura J.

    2016-01-01

    Contemporary African-American classical composers Cedric Adderley, John Lane, and Trevor Weston intertwine strands of culture and individual experience to produce musical works whose distinct designs offer cultural resources that music educators can use to integrate diversity into instructional settings. Of special interest is their ability to…

  4. Evidence of common signatures of selection in the genomes of West African cattle and the Yoruba human population

    Science.gov (United States)

    In 1954, Allison found that the sickle-cell anemia mutation in the beta hemoglobin gene was highly prevalent in West African people because it is protective against malaria, so carriers would thrive and leave offspring in spite of the genetic disease. This is one of the earliest evidences of an envi...

  5. Treatment of Posttraumatic Stress Disorder by Trained Lay Counselors in an African Refugee Settlement: A Randomized Controlled Trial

    Science.gov (United States)

    Neuner, Frank; Onyut, Patience Lamaro; Ertl, Verena; Odenwald, Michael; Schauer, Elisabeth; Elbert, Thomas

    2008-01-01

    Traumatic stress due to conflict and war causes major mental health problems in many resource-poor countries. The objective of this study was to examine whether trained lay counselors can carry out effective treatment of posttraumatic stress disorder (PTSD) in a refugee settlement. In a randomized controlled dissemination trial in Uganda with 277…

  6. The Jackprot Simulation Couples Mutation Rate with Natural Selection to Illustrate How Protein Evolution Is Not Random

    Science.gov (United States)

    Espinosa, Avelina; Bai, Chunyan Y.

    2016-01-01

    Protein evolution is not a random process. Views which attribute randomness to molecular change, deleterious nature to single-gene mutations, insufficient geological time, or population size for molecular improvements to occur, or invoke “design creationism” to account for complexity in molecular structures and biological processes, are unfounded. Scientific evidence suggests that natural selection tinkers with molecular improvements by retaining adaptive peptide sequence. We used slot-machine probabilities and ion channels to show biological directionality on molecular change. Because ion channels reside in the lipid bilayer of cell membranes, their residue location must be in balance with the membrane's hydrophobic/philic nature; a selective “pore” for ion passage is located within the hydrophobic region. We contrasted the random generation of DNA sequence for KcsA, a bacterial two-transmembrane-domain (2TM) potassium channel, from Streptomyces lividans, with an under-selection scenario, the “jackprot,” which predicted much faster evolution than by chance. We wrote a computer program in JAVA APPLET version 1.0 and designed an online interface, The Jackprot Simulation http://faculty.rwu.edu/cbai/JackprotSimulation.htm, to model a numerical interaction between mutation rate and natural selection during a scenario of polypeptide evolution. Winning the “jackprot,” or highest-fitness complete-peptide sequence, required cumulative smaller “wins” (rewarded by selection) at the first, second, and third positions in each of the 161 KcsA codons (“jackdons” that led to “jackacids” that led to the “jackprot”). The “jackprot” is a didactic tool to demonstrate how mutation rate coupled with natural selection suffices to explain the evolution of specialized proteins, such as the complex six-transmembrane (6TM) domain potassium, sodium, or calcium channels. Ancestral DNA sequences coding for 2TM-like proteins underwent nucleotide

  7. The Jackprot Simulation Couples Mutation Rate with Natural Selection to Illustrate How Protein Evolution Is Not Random.

    Science.gov (United States)

    Paz-Y-Miño C, Guillermo; Espinosa, Avelina; Bai, Chunyan Y

    2011-09-01

    Protein evolution is not a random process. Views which attribute randomness to molecular change, deleterious nature to single-gene mutations, insufficient geological time, or population size for molecular improvements to occur, or invoke "design creationism" to account for complexity in molecular structures and biological processes, are unfounded. Scientific evidence suggests that natural selection tinkers with molecular improvements by retaining adaptive peptide sequence. We used slot-machine probabilities and ion channels to show biological directionality on molecular change. Because ion channels reside in the lipid bilayer of cell membranes, their residue location must be in balance with the membrane's hydrophobic/philic nature; a selective "pore" for ion passage is located within the hydrophobic region. We contrasted the random generation of DNA sequence for KcsA, a bacterial two-transmembrane-domain (2TM) potassium channel, from Streptomyces lividans, with an under-selection scenario, the "jackprot," which predicted much faster evolution than by chance. We wrote a computer program in JAVA APPLET version 1.0 and designed an online interface, The Jackprot Simulation http://faculty.rwu.edu/cbai/JackprotSimulation.htm, to model a numerical interaction between mutation rate and natural selection during a scenario of polypeptide evolution. Winning the "jackprot," or highest-fitness complete-peptide sequence, required cumulative smaller "wins" (rewarded by selection) at the first, second, and third positions in each of the 161 KcsA codons ("jackdons" that led to "jackacids" that led to the "jackprot"). The "jackprot" is a didactic tool to demonstrate how mutation rate coupled with natural selection suffices to explain the evolution of specialized proteins, such as the complex six-transmembrane (6TM) domain potassium, sodium, or calcium channels. Ancestral DNA sequences coding for 2TM-like proteins underwent nucleotide "edition" and gene duplications to generate the 6

  8. Pseudo cluster randomization: a treatment allocation method to minimize contamination and selection bias.

    NARCIS (Netherlands)

    Borm, G.F.; Melis, R.J.F.; Teerenstra, S.; Peer, P.G.M.

    2005-01-01

    In some clinical trials, treatment allocation on a patient level is not feasible, and whole groups or clusters of patients are allocated to the same treatment. If, for example, a clinical trial is investigating the efficacy of various patient coaching methods and randomization is done on a patient

  9. Effect of African leafy vegetables on the micronutrient status of mildly deficient farm-school children in South Africa: a randomized controlled study.

    Science.gov (United States)

    van der Hoeven, Marinka; Faber, Mieke; Osei, Jennifer; Kruger, Annamarie; Smuts, Cornelius M

    2016-04-01

    A randomized controlled trial was conducted to assess the effect of African leafy vegetable (ALV) consumption on Fe, Zn and vitamin A status in children. Children were randomly allocated to receive either a 300 g cooked ALV dish and school meal starch (n 86) or the normal school meal (n 81) five times per week for three months. ALV in the dish consisted mainly of Amaranthus cruentus (at least 80 %) and the remainder of Cleome gynandra, Cucurbita maxima or Vigna unguiculata. Nutrient content and consumer acceptance of the ALV dish were also determined. North West Province, South Africa. Grade R to grade 4 children (6-12 years old) of two farm schools. The ALV dish contributed 11·6-15·8 mg Fe and 1·4-3·7 mg Zn. At baseline, prevalence of deficiencies in the intervention group was 16·0 %, 16·3 %, 7·0 % and 75·6 %, respectively, for anaemia (Hb<11·5 g/dl), Fe (serum ferritin<15 µg/l), vitamin A (serum retinol<20 μg/dl) and Zn (serum Zn<65 μg/dl); and in the control group 10·5 %, 18·5 %, 2·5 % and 75·3 %, respectively. No significant estimated intervention effect was found. This randomized controlled trial showed that ALV were unable to improve serum retinol, serum ferritin or Hb if there are only mild deficiencies present. Furthermore, despite the low Zn status in the study population, ALV consumption did not improve serum Zn concentrations either.

  10. A Virtual World Versus Face-to-Face Intervention Format to Promote Diabetes Self-Management Among African American Women: A Pilot Randomized Clinical Trial.

    Science.gov (United States)

    Rosal, Milagros C; Heyden, Robin; Mejilla, Roanne; Capelson, Roberta; Chalmers, Karen A; Rizzo DePaoli, Maria; Veerappa, Chetty; Wiecha, John M

    2014-10-24

    Virtual world environments have the potential to increase access to diabetes self-management interventions and may lower cost. We tested the feasibility and comparative effectiveness of a virtual world versus a face-to-face diabetes self-management group intervention. We recruited African American women with type 2 diabetes to participate in an 8-week diabetes self-management program adapted from Power to Prevent, a behavior-change in-person group program for African Americans with diabetes or pre-diabetes. The program is social cognitive theory-guided, evidence-based, and culturally tailored. Participants were randomized to participate in the program via virtual world (Second Life) or face-to-face, both delivered by a single intervention team. Blinded assessors conducted in-person clinical (HbA1c), behavioral, and psychosocial measurements at baseline and 4-month follow-up. Pre-post differences within and between intervention groups were assessed using t tests and chi-square tests (two-sided and intention-to-treat analyses for all comparisons). Participants (N=89) were an average of 52 years old (SD 10), 60% had ≤high school, 82% had household incomes

  11. Presence of psychoactive substances in oral fluid from randomly selected drivers in Denmark

    DEFF Research Database (Denmark)

    Simonsen, K. Wiese; Steentoft, A.; Hels, Tove

    2012-01-01

    This roadside study is the Danish part of the EU-project DRUID (Driving under the Influence of Drugs, Alcohol, and Medicines) and included three representative regions in Denmark. Oral fluid samples (n = 3002) were collected randomly from drivers using a sampling scheme stratified by time, season...... of narcotic drugs. It can be concluded that driving under the influence of drugs is as serious a road safety problem as drunk driving.......This roadside study is the Danish part of the EU-project DRUID (Driving under the Influence of Drugs, Alcohol, and Medicines) and included three representative regions in Denmark. Oral fluid samples (n = 3002) were collected randomly from drivers using a sampling scheme stratified by time, season...

  12. Presence of psychoactive substances in oral fluid from randomly selected drivers in Denmark

    DEFF Research Database (Denmark)

    Simonsen, Kirsten Wiese; Steentoft, Anni; Hels, Tove

    2012-01-01

    This roadside study is the Danish part of the EU-project DRUID (Driving under the Influence of Drugs, Alcohol, and Medicines) and included three representative regions in Denmark. Oral fluid samples (n = 3002) were collected randomly from drivers using a sampling scheme stratified by time, season....... It can be concluded that driving under the influence of drugs is as serious a road safety problem as drunk driving.......This roadside study is the Danish part of the EU-project DRUID (Driving under the Influence of Drugs, Alcohol, and Medicines) and included three representative regions in Denmark. Oral fluid samples (n = 3002) were collected randomly from drivers using a sampling scheme stratified by time, season...

  13. Feature selection and classification of mechanical fault of an induction motor using random forest classifier

    Directory of Open Access Journals (Sweden)

    Raj Kumar Patel

    2016-09-01

    Full Text Available Fault detection and diagnosis is the most important technology in condition-based maintenance (CBM system for rotating machinery. This paper experimentally explores the development of a random forest (RF classifier, a recently emerged machine learning technique, for multi-class mechanical fault diagnosis in bearing of an induction motor. Firstly, the vibration signals are collected from the bearing using accelerometer sensor. Parameters from the vibration signal are extracted in the form of statistical features and used as input feature for the classification problem. These features are classified through RF classifiers for four class problems. The prime objective of this paper is to evaluate effectiveness of random forest classifier on bearing fault diagnosis. The obtained results compared with the existing artificial intelligence techniques, neural network. The analysis of results shows the better performance and higher accuracy than the well existing techniques.

  14. The relationship between demographic variables and leisure perceptions of selected South African first year university students / J.T. Weilbach.

    OpenAIRE

    Weilbach, Johannes Theron

    2013-01-01

    Participation in campus leisure and recreation programmes can provide university students with various benefits, but the provision of effective leisure programmes are complicated by the changes that have taken place in the demographic composition of the student population attending South African universities. Increases in the proportion of black students attending university, and decreases in the proportion of white students means that current students possibly exhibit leisure behaviours that...

  15. Selective nerve root blocks vs. caudal epidural injection for single level prolapsed lumbar intervertebral disc - A prospective randomized study.

    Science.gov (United States)

    Singh, Sudhir; Kumar, Sanjiv; Chahal, Gaurav; Verma, Reetu

    2017-01-01

    Chronic lumbar radiculopathy has a lifetime prevalence of 5.3% in men and 3.7% in women. It usually resolves spontaneously, but up to 30% cases will have pronounced symptoms even after one year. A prospective randomized single-blind study was conducted to compare the efficacy of caudal epidural steroid injection and selective nerve root block in management of pain and disability in cases of lumbar disc herniation. Eighty patients with confirmed single-level lumbar disc herniation were equally divided in two groups: (a) caudal epidural and (b) selective nerve root block group, by a computer-generated random allocation method. The caudal group received three injections of steroid mixed with local anesthetics while selective nerve root block group received single injection of steroid mixed with local anesthetic agent. Patients were assessed for pain relief and reduction in disability. In SNRB group, pain reduced by more than 50% up till 6 months, while in caudal group more than 50% reduction of pain was maintained till 1 year. The reduction in ODI in SNRB group was 52.8% till 3 months, 48.6% till 6 months, and 46.7% at 1 year, while in caudal group the improvement was 59.6%, 64.6%, 65.1%, and 65.4% at corresponding follow-up periods, respectively. Caudal epidural block is an easy and safe method with better pain relief and improvement in functional disability than selective nerve root block. Selective nerve root block injection is technically more demanding and has to be given by a skilled anesthetist.

  16. A randomized controlled trial of the effects of nurse case manager and community health worker team interventions in urban African-Americans with type 2 diabetes.

    Science.gov (United States)

    Gary, Tiffany L; Batts-Turner, Marian; Bone, Lee R; Yeh, Hsin-Chieh; Wang, Nae-Yuh; Hill-Briggs, Felicia; Levine, David M; Powe, Neil R; Hill, Martha N; Saudek, Christopher; McGuire, Maura; Brancati, Frederick L

    2004-02-01

    The objective of the study was to determine the effectiveness and cost-effectiveness of primary care and community-oriented interventions in managing HbA1c, blood pressure, and lipids, and reducing hospitalizations and emergency room visits over 2 years. We describe an ongoing, randomized controlled trial of 542 urban African-Americans with type 2 diabetes ages 25 years and older who are members of a university-affiliated managed-care organization in Baltimore, MD. The participants are 74% female, have a mean age of 58 years, and 35% have yearly incomes greater than 7500 US dollars. Participants were randomized to one of two intervention groups for a period of 2 years: (1) usual medical care plus minimal telephone intervention implemented by a trained lay health educator (control group) or (2) usual medical care plus intensive intervention implemented by a nurse case manager (NCM)/community health worker (CHW) team. The intensive NCM/CHW team executes individual plans of care using evidence-based algorithms that focus on traditional diabetes self-management, screening and management of diabetes-related complications, and social issues surrounding diabetes care. Face-to-face NCM visits are conducted in the clinic once per year and CHW visits are conducted in the participant's home one to three times per year, both with additional follow-up contacts as needed. Written and verbal feedback (when necessary) is provided to the participant's primary care physician. All participants are expected to attend a 24-month follow-up visit where data are collected by interviewers blinded to intervention assignment. As of May 1, 2003, recruitment is complete, interventions are being fully implemented, and 24-month follow-up visits are beginning. Baseline sociodemographic characteristics, health-care utilization, health behaviors, and clinical characteristics of the study population are reported. This study is designed to test the hypothesis that a primary-care-based NCM plus CHW

  17. Specific and selective probes for Staphylococcus aureus from phage-displayed random peptide libraries.

    Science.gov (United States)

    De Plano, Laura M; Carnazza, Santina; Messina, Grazia M L; Rizzo, Maria Giovanna; Marletta, Giovanni; Guglielmino, Salvatore P P

    2017-09-01

    Staphylococcus aureus is a major human pathogen causing health care-associated and community-associated infections. Early diagnosis is essential to prevent disease progression and to reduce complications that can be serious. In this study, we selected, from a 9-mer phage peptide library, a phage clone displaying peptide capable of specific binding to S. aureus cell surface, namely St.au9IVS5 (sequence peptide RVRSAPSSS).The ability of the isolated phage clone to interact specifically with S. aureus and the efficacy of its bacteria-binding properties were established by using enzyme linked immune-sorbent assay (ELISA). We also demonstrated by Western blot analysis that the most reactive and selective phage peptide binds a 78KDa protein on the bacterial cell surface. Furthermore, we observed selectivity of phage-bacteria-binding allowing to identify clinical isolates of S. aureus in comparison with a panel of other bacterial species. In order to explore the possibility of realizing a selective bacteria biosensor device, based on immobilization of affinity-selected phage, we have studied the physisorbed phage deposition onto a mica surface. Atomic Force Microscopy (AFM) was used to determine the organization of phage on mica surface and then the binding performance of mica-physisorbed phage to bacterial target was evaluated during the time by fluorescent microscopy. The system is able to bind specifically about 50% of S. aureus cells after 15' and 90% after one hour. Due to specificity and rapidness, this biosensing strategy paves the way to the further development of new cheap biosensors to be used in developing countries, as lab-on-chip (LOC) to detect bacterial agents in clinical diagnostics applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Selection of locations of knots for linear splines in random regression test-day models.

    Science.gov (United States)

    Jamrozik, J; Bohmanova, J; Schaeffer, L R

    2010-04-01

    Using spline functions (segmented polynomials) in regression models requires the knowledge of the location of the knots. Knots are the points at which independent linear segments are connected. Optimal positions of knots for linear splines of different orders were determined in this study for different scenarios, using existing estimates of covariance functions and an optimization algorithm. The traits considered were test-day milk, fat and protein yields, and somatic cell score (SCS) in the first three lactations of Canadian Holsteins. Two ranges of days in milk (from 5 to 305 and from 5 to 365) were taken into account. In addition, four different populations of Holstein cows, from Australia, Canada, Italy and New Zealand, were examined with respect to first lactation (305 days) milk only. The estimates of genetic and permanent environmental covariance functions were based on single- and multiple-trait test-day models, with Legendre polynomials of order 4 as random regressions. A differential evolution algorithm was applied to find the best location of knots for splines of orders 4 to 7 and the criterion for optimization was the goodness-of-fit of the spline covariance function. Results indicated that the optimal position of knots for linear splines differed between genetic and permanent environmental effects, as well as between traits and lactations. Different populations also exhibited different patterns of optimal knot locations. With linear splines, different positions of knots should therefore be used for different effects and traits in random regression test-day models when analysing milk production traits.

  19. African Journals Online: Health

    African Journals Online (AJOL)

    Items 1 - 50 of 167 ... c) Update articles surveying the present state of knowledge in selected fields of Dentistry and oral health. d) Critical or analytical reviews in the ... African Journal of Paediatric Nephrology is the official Journal of the African Paediatric Nephrology Association (AFPNA). The journal is dedicated to increasing ...

  20. African Journals Online (AJOL)

    African Journals Online (AJOL)

    OGIRISI: a New Journal of African Studies; The Influence of Motivation on Employees' Performance: A Study of Some Selected Firms in Anambra State AFRREV IJAH: An International Journal of Arts and Humanities; Educational leadership and management: theory, policy and practice. South African Journal of Education ...

  1. 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

  2. Effect of low-dose spironolactone on resistant hypertension in type 2 diabetes mellitus: a randomized controlled trial in a sub-Saharan African population.

    Science.gov (United States)

    Djoumessi, Romance Nguetse; Noubiap, Jean Jacques N; Kaze, Francois Folefack; Essouma, Mickael; Menanga, Alain Patrick; Kengne, Andre Pascal; Mbanya, Jean Claude; Sobngwi, Eugene

    2016-03-23

    Low-dose spironolactone has been proven to be effective for resistant hypertension in the general population, but this has yet to be confirmed in type 2 diabetic (T2DM) patients. We assessed the efficacy of a low-dose spironolactone on resistant hypertension in a sub-Saharan African population of T2DM patients from Cameroon. This was a four-week single blinded randomized controlled trial in 17 subjects presenting with resistant hypertension in specialized diabetes care units in Cameroon. They were randomly assigned to treatment with a daily 25 mg of spironolactone (n = 9) or to an alternative antihypertensive regimen (n = 8), on top of any ongoing regimen and prevailing lifestyle prescriptions. They were seen at the start of the treatment, then 2 and 4 weeks later. The primary outcome was change in office and self-measured blood pressure (BP) during follow-up, and secondary outcomes were changes in serum potassium, sodium, and creatinine levels. Compared with alternative treatment, low-dose spironolactone was associated with significant decrease in office systolic BP (-33 vs. -14 mmHg; p = 0.024), and in diastolic BP (-14 vs. -5 mmHg; p = 0.006). After 1 month of spironolactone, all the patients were controlled based on BP below 130/80 mmHg, with significant office BP reduction from 158 ± 17/86 ± 11 to 125 ± 11/72 ± 8, vs. 158 ± 8/94 ± 8 to 144 ± 17/89 ± 12 mmHg in the alternative treatment group. There was no significant variation in sodium and creatinine levels in both groups, but a mild increase of potassium levels in the spironolactone group. Add-on low-dose spironolactone was effective in reducing BP to optimal levels in T2DM Cameroonian patients despite mild increase in serum potassium. Trial registration ClinicalTrials.gov Identifier NCT02426099. Date of registration April 2015.

  3. Design of a cluster-randomized controlled trial of a diabetes prevention program within African-American churches: The Fit Body and Soul study.

    Science.gov (United States)

    Williams, Lovoria B; Sattin, Richard W; Dias, James; Garvin, Jane T; Marion, Lucy; Joshua, Thomas; Kriska, Andrea; Kramer, M Kaye; Echouffo-Tcheugui, Justin B; Freeman, Arin; Narayan, K M Venkat

    2013-03-01

    Evidence from varied community settings has shown that the Group Lifestyle Balance (GLB) Program and other adaptations of the Diabetes Prevention Program (DPP) intervention are effective in lowering diabetes risk. Most DPP data originated from studies of pre-diabetic whites, with only sparse evidence of the effect of DPP in African Americans (AAs) in community settings. This paper describes the design, methods, baseline characteristics and cost effective measures, of a single-blinded, cluster-randomized trial of a faith-based adaptation of the GLB program, Fit Body and Soul (FBAS). The major aims are to test efficacy and cost utility of FBAS in twenty AA churches. Randomization occurred at the church level and 604 AA overweight/obese (BMI≥25kg/m(2)) adults with fasting plasma glucose range from normal to pre-diabetic received either FBAS or a health-education comparison program. FBAS is a group-based, multi-level intervention delivered by trained church health advisors (health professionals from within the church), with the goal of ≥7% weight loss, achieved through increasing physical activity, healthy eating and behavior modification. The primary outcome is weight change at 12weeks post intervention. Secondary outcomes include hemoglobin A1C, fasting plasma glucose, waist circumference, blood pressure, physical activity level, quality of life measures, and cost-effectiveness. FBAS is the largest known cohort of AAs enrolled in a faith-based DPP translation. Reliance on health professionals from within the church for program implementation and the cost analysis are unique aspects of this trial. The design provides a model for faith-based DPPs and holds promise for program sustainability and widespread dissemination. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Study protocol for a randomized clinical trial of a fatherhood intervention for African American non-resident fathers: Can we improve father and child outcomes?

    Science.gov (United States)

    Julion, Wrenetha A; Sumo, Jen'nea; Bounds, Dawn T; Breitenstein, Susan M; Schoeny, Michael; Gross, Deborah; Fogg, Louis

    2016-07-01

    African American (AA) fathers who live apart from their children face multiple obstacles to consistent and positive involvement with their children. Consequently, significant numbers of children are bereft of their father's positive involvement. Intervention research that is explicitly focused on promoting the positive involvement of non-resident AA fathers with their young children is limited. The purpose of this article is to describe the study protocol of a randomized trial (RCT) designed to test the Building Bridges to Fatherhood program against a financial literacy comparison condition; and discuss early implementation challenges. Fathers (n=180) are recruited to attend 10 group meetings, reimbursed for transportation, given dinner and activity vouchers for spending time with their child, and incentivized with a $40 gift card at each data collection time point. Mothers are incentivized ($40 gift card) at data collection and must be amenable to father child interaction. Intervention targets include father psychological well-being, parenting competence, communication, problem-solving ability; father-mother relationship quality; and child behavioral and emotional/social development. To date, 57 fathers have been randomized to study condition. Recruitment has been influenced by father and mother hesitancy and the logistics of reaching and maintaining contact with participants. Strategies to surmount challenges to father and mother recruitment and engagement have been developed. The prospective benefits of positive father involvement to children, fathers and families outweigh the challenges associated with community-based intervention research. The findings from this RCT can inform the body of knowledge on engaging AA non-resident fathers in culturally relevant fatherhood programming. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Efficacy of an HIV intervention in reducing high-risk human papillomavirus, nonviral sexually transmitted infections, and concurrency among African American women: a randomized-controlled trial.

    Science.gov (United States)

    Wingood, Gina M; Diclemente, Ralph J; Robinson-Simpson, Lashun; Lang, Delia L; Caliendo, Angela; Hardin, James W

    2013-06-01

    This trial evaluated the efficacy of an HIV-intervention condition, relative to a health-promotion condition, in reducing incidence of nonviral sexually transmitted infections (STIs; Chlamydia, gonorrhea, and trichomoniasis), oncogenic human papillomavirus (HPV) subtypes 16 and 18, sexual concurrency, and other HIV-associated behaviors over a 12-month period. Randomized-controlled trial. Data analysts blinded to treatment allocation. Kaiser Permanente, GA. A random sample of 848 African American women. The two 4-hour HIV intervention sessions were based on Social Cognitive Theory and the Theory of Gender and Power. The intervention was designed to enhance participants' self-sufficiency and attitudes and skills associated with condom use. The HIV intervention also encouraged STI testing and treatment of male sex partners and reducing vaginal douching and individual and male partner concurrency. Incident nonviral STIs. In generalized estimating equations' analyses, over the 12-month follow-up, participants in the HIV intervention, relative to the comparison, were less likely to have nonviral incident STIs (odds ratio [OR] = 0.62; 95% confidence interval [CI]: 0.40 to 0.96; P = 0.033) and incident high-risk HPV infection (OR = 0.37; 95% CI: 0.18 to 0.77; P = 0.008) or concurrent male sex partners (OR = 0.55; 95% CI: 0.37 to 0.83; P = 0.005). In addition, intervention participants were less likely to report multiple male sex partners, more likely to use condoms during oral sex, more likely to inform their main partner of their STI test results, encourage their main partner to seek STI testing, report that their main partner was treated for STIs, and report not douching. This is the first trial to demonstrate that an HIV intervention can achieve reductions in nonviral STIs, high-risk HPV, and individual concurrency.

  6. A phase 2b randomized, controlled trial of the efficacy of the GMZ2 malaria vaccine in African children

    DEFF Research Database (Denmark)

    Sirima, Sodiomon B; Mordmüller, Benjamin; Milligan, Paul

    2016-01-01

    randomized to receive three injections of either 100μg GMZ2 adjuvanted with aluminum hydroxide or a control vaccine (rabies) four weeks apart and were followed up for six months to measure the incidence of malaria defined as fever or history of fever and a parasite density ⩾5000/μL. RESULTS: A cohort of 1849...... in the rabies vaccine group and 14 in the GMZ2 group), VE 27% (95% CI -44%, 63%). CONCLUSIONS: GMZ2 is the first blood-stage malaria vaccine to be evaluated in a large multicenter trial. GMZ2 was well tolerated and immunogenic, and reduced the incidence of malaria, but efficacy would need to be substantially...

  7. Community health workers can improve child growth of antenatally-depressed, South African mothers: a cluster randomized controlled trial.

    Science.gov (United States)

    Tomlinson, Mark; Rotheram-Borus, Mary Jane; Harwood, Jessica; le Roux, Ingrid M; O'Connor, Mary; Worthman, Carol

    2015-09-23

    Maternal antenatal depression has long-term consequences for children's health. We examined if home visits by community health workers (CHW) can improve growth outcomes for children of mothers who are antenatally depressed. A cluster randomized controlled trial of all pregnant, neighbourhood women in Cape Town, South Africa. Almost all pregnant women (98 %, N = 1238) were recruited and assessed during pregnancy, two weeks post-birth (92 %) and 6 months post-birth (88 %). Pregnant women were randomized to either: 1) Standard Care (SC), which provided routine antenatal care; or 2) an intervention, The Philani Intervention Program (PIP), which included SC and home visits by CHW trained as generalists (M = 11 visits). Child standardized weight, length, and weight by length over 6 months based on maternal antenatal depression and intervention condition. Depressed mood was similar across the PIP and SC conditions both antenatally (16.5 % rate) and at 6 months (16.7 %). The infants of depressed pregnant women in the PIP group were similar in height (height-for-age Z scores) to the children of non-depressed mothers in both the PIP and the SC conditions, but significantly taller at 6 months of age than the infants of pregnant depressed mothers in the SC condition. The intervention did not moderate children's growth. Depressed SC mothers tended to have infants less than two standard deviations in height on the World Health Organization's norms at two weeks post-birth compared to infants of depressed PIP mothers and non-depressed mothers in both conditions. A generalist, CHW-delivered home visiting program improved infant growth, even when mothers' depression was not reduced. Focusing on maternal caretaking of infants, even when mothers are depressed, is critical in future interventions. ClinicalTrials.gov registration # NCT00996528 . October 15, 2009.

  8. A phase 2b randomized, controlled trial of the efficacy of the GMZ2 malaria vaccine in African children.

    Science.gov (United States)

    Sirima, Sodiomon B; Mordmüller, Benjamin; Milligan, Paul; Ngoa, Ulysse Ateba; Kironde, Fred; Atuguba, Frank; Tiono, Alfred B; Issifou, Saadou; Kaddumukasa, Mark; Bangre, Oscar; Flach, Clare; Christiansen, Michael; Bang, Peter; Chilengi, Roma; Jepsen, Søren; Kremsner, Peter G; Theisen, Michael

    2016-08-31

    GMZ2 is a recombinant protein malaria vaccine, comprising two blood-stage antigens of Plasmodium falciparum, glutamate-rich protein and merozoite surface protein 3. We assessed efficacy of GMZ2 in children in Burkina Faso, Gabon, Ghana and Uganda. Children 12-60months old were randomized to receive three injections of either 100μg GMZ2 adjuvanted with aluminum hydroxide or a control vaccine (rabies) four weeks apart and were followed up for six months to measure the incidence of malaria defined as fever or history of fever and a parasite density ⩾5000/μL. A cohort of 1849 children were randomized, 1735 received three doses of vaccine (868 GMZ2, 867 control-vaccine). There were 641 malaria episodes in the GMZ2/Alum group and 720 in the control group. In the ATP analysis, vaccine efficacy (VE), adjusted for age and site was 14% (95% confidence interval [CI]: 3.6%, 23%, p-value=0.009). In the ITT analysis, age-adjusted VE was 11.3% (95% CI 2.5%, 19%, p-value=0.013). VE was higher in older children. In GMZ2-vaccinated children, the incidence of malaria decreased with increasing vaccine-induced anti-GMZ2 IgG concentration. There were 32 cases of severe malaria (18 in the rabies vaccine group and 14 in the GMZ2 group), VE 27% (95% CI -44%, 63%). GMZ2 is the first blood-stage malaria vaccine to be evaluated in a large multicenter trial. GMZ2 was well tolerated and immunogenic, and reduced the incidence of malaria, but efficacy would need to be substantially improved, using a more immunogenic formulation, for the vaccine to have a public health role. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Cryotherapy Reduces Progression of Cervical Intraepithelial Neoplasia Grade 1 in South African HIV-Infected Women: A Randomized, Controlled Trial.

    Science.gov (United States)

    Firnhaber, Cynthia; Swarts, Avril; Goeieman, Bridgette; Rakhombe, Ntombi; Mulongo, Masangu; Williamson, Anna-Lise; Michelow, Pam; Ramotshela, Sibongile; Faesen, Mark; Levin, Simon; Wilkin, Timothy

    2017-12-15

    HIV-infected women are at an increased risk of cervical cancer, especially in resource-limited countries. Cervical cancer prevention strategies focus treating cervical high-grade squamous intraepithelial lesions (HSIL). The management of low-grade squamous intraepithelial lesions (LSIL) in HIV-infected women is unknown. HIV treatment clinic in Johannesburg, South Africa. We randomized HIV-infected women with histologic cervical LSIL to cervical cryotherapy vs. no treatment (standard of care). Cervical high-risk human papillomavirus testing (hrHPV) was performed at baseline. All women underwent cervical cytology and colposcopic biopsies 12 months after enrollment. The primary end point was HSIL on histology at month 12. Chi-square was used to compare arms. Overall, 220 HIV-infected women were randomized to cryotherapy (n = 112) or no treatment (n = 108). Median age was 38 years, 94% were receiving antiretroviral therapy; median CD4 was 499 cells per cubic millimeter, and 59% were hrHPV positive. Cryotherapy reduced progression to HSIL: 2/99 (2%) in the cryotherapy arm and 15/103 (15%) in the no treatment arm developed HSIL, 86% reduction (95% confidence interval: 41% to 97%; P = 0.002). Among 17 HSIL end points, 16 were hrHPV+ at baseline. When restricting the analysis to hrHPV+ women, HSIL occurred in 2/61 (3%) in the cryotherapy arm vs. 14/54 (26%) in the no treatment arm, 87% reduction (95% confidence interval: 47% to 97%; P = 0.0004). Participants in the cryotherapy arm experienced greater regression to normal histology and improved cytologic outcomes. Treatment of cervical LSIL with cryotherapy decreased progression to HSIL among HIV-infected women especially if hrHPV positive. These results support treatment of LSIL in human papillomavirus test-and-treat approaches for cervical cancer prevention in resource-constrained settings.

  10. A Randomized Controlled Trial of Cognitive Debiasing Improves Assessment and Treatment Selection for Pediatric Bipolar Disorder

    Science.gov (United States)

    Jenkins, Melissa M.; Youngstrom, Eric A.

    2015-01-01

    Objective This study examined the efficacy of a new cognitive debiasing intervention in reducing decision-making errors in the assessment of pediatric bipolar disorder (PBD). Method The study was a randomized controlled trial using case vignette methodology. Participants were 137 mental health professionals working in different regions of the US (M=8.6±7.5 years of experience). Participants were randomly assigned to a (1) brief overview of PBD (control condition), or (2) the same brief overview plus a cognitive debiasing intervention (treatment condition) that educated participants about common cognitive pitfalls (e.g., base-rate neglect; search satisficing) and taught corrective strategies (e.g., mnemonics, Bayesian tools). Both groups evaluated four identical case vignettes. Primary outcome measures were clinicians’ diagnoses and treatment decisions. The vignette characters’ race/ethnicity was experimentally manipulated. Results Participants in the treatment group showed better overall judgment accuracy, p < .001, and committed significantly fewer decision-making errors, p < .001. Inaccurate and somewhat accurate diagnostic decisions were significantly associated with different treatment and clinical recommendations, particularly in cases where participants missed comorbid conditions, failed to detect the possibility of hypomania or mania in depressed youths, and misdiagnosed classic manic symptoms. In contrast, effects of patient race were negligible. Conclusions The cognitive debiasing intervention outperformed the control condition. Examining specific heuristics in cases of PBD may identify especially problematic mismatches between typical habits of thought and characteristics of the disorder. The debiasing intervention was brief and delivered via the Web; it has the potential to generalize and extend to other diagnoses as well as to various practice and training settings. PMID:26727411

  11. 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

  12. Role of selective V2-receptor-antagonism in septic shock: a randomized, controlled, experimental study

    OpenAIRE

    Rehberg, Sebastian; Ertmer, Christian; Lange, Matthias; Morelli, Andrea; Whorton, Elbert; Strohhäcker, Anne-Katrin; Dünser, Martin Wolfgang; Lipke, Erik; Kampmeier, Tim G; Aken, Hugo; Traber, Daniel L; Westphal, Martin

    2010-01-01

    ABSTRACT : INTRODUCTION : V2-receptor (V2R) stimulation potentially aggravates sepsis-induced vasodilation, fluid accumulation and microvascular thrombosis. Therefore, the present study was performed to determine the effects of a first-line therapy with the selective V2R-antagonist (Propionyl1-D-Tyr(Et)2-Val4-Abu6-Arg8,9)-Vasopressin on cardiopulmonary hemodynamics and organ function vs. the mixed V1aR/V2R-agonist arginine vasopressin (AVP) or placebo in an established ovine model of septic s...

  13. Conflicts of Interest, Selective Inertia, and Research Malpractice in Randomized Clinical Trials: An Unholy Trinity.

    Science.gov (United States)

    Berger, Vance W

    2015-08-01

    Recently a great deal of attention has been paid to conflicts of interest in medical research, and the Institute of Medicine has called for more research into this important area. One research question that has not received sufficient attention concerns the mechanisms of action by which conflicts of interest can result in biased and/or flawed research. What discretion do conflicted researchers have to sway the results one way or the other? We address this issue from the perspective of selective inertia, or an unnatural selection of research methods based on which are most likely to establish the preferred conclusions, rather than on which are most valid. In many cases it is abundantly clear that a method that is not being used in practice is superior to the one that is being used in practice, at least from the perspective of validity, and that it is only inertia, as opposed to any serious suggestion that the incumbent method is superior (or even comparable), that keeps the inferior procedure in use, to the exclusion of the superior one. By focusing on these flawed research methods we can go beyond statements of potential harm from real conflicts of interest, and can more directly assess actual (not potential) harm.

  14. 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.

  15. Content analysis of a stratified random selection of JVME articles: 1974-2004.

    Science.gov (United States)

    Olson, Lynne E

    2011-01-01

    A content analysis was performed on a random sample (N = 168) of 25% of the articles published in the Journal of Veterinary Medical Education (JVME) per year from 1974 through 2004. Over time, there were increased numbers of authors per paper, more cross-institutional collaborations, greater prevalence of references or endnotes, and lengthier articles, which could indicate a trend toward publications describing more complex or complete work. The number of first authors that could be identified as female was greatest for the most recent time period studied (2000-2004). Two different categorization schemes were created to assess the content of the publications. The first categorization scheme identified the most frequently published topics as admissions, descriptions of courses, the effect of changing teaching methods, issues facing the profession, and examples of uses of technology. The second categorization scheme identified the subset of articles that described medical education research on the basis of the purpose of the research, which represented only 14% of the sample articles (24 of 168). Of that group, only three of 24, or 12%, represented studies based on a firm conceptual framework that could be confirmed or refuted by the study's results. The results indicate that JVME is meeting its broadly based mission and that publications in the veterinary medical education literature have features common to publications in medicine and medical education.

  16. Capturing the Flatness of a peer-to-peer lending network through random and selected perturbations

    Science.gov (United States)

    Karampourniotis, Panagiotis D.; Singh, Pramesh; Uparna, Jayaram; Horvat, Emoke-Agnes; Szymanski, Boleslaw K.; Korniss, Gyorgy; Bakdash, Jonathan Z.; Uzzi, Brian

    Null models are established tools that have been used in network analysis to uncover various structural patterns. They quantify the deviance of an observed network measure to that given by the null model. We construct a null model for weighted, directed networks to identify biased links (carrying significantly different weights than expected according to the null model) and thus quantify the flatness of the system. Using this model, we study the flatness of Kiva, a large international crownfinancing network of borrowers and lenders, aggregated to the country level. The dataset spans the years from 2006 to 2013. Our longitudinal analysis shows that flatness of the system is reducing over time, meaning the proportion of biased inter-country links is growing. We extend our analysis by testing the robustness of the flatness of the network in perturbations on the links' weights or the nodes themselves. Examples of such perturbations are event shocks (e.g. erecting walls) or regulatory shocks (e.g. Brexit). We find that flatness is unaffected by random shocks, but changes after shocks target links with a large weight or bias. The methods we use to capture the flatness are based on analytics, simulations, and numerical computations using Shannon's maximum entropy. Supported by ARL NS-CTA.

  17. Benefits of Selected Physical Exercise Programs in Detention: A Randomized Controlled Study

    Directory of Open Access Journals (Sweden)

    Claudia Battaglia

    2013-10-01

    Full Text Available The aim of the study was to determine which kind of physical activity could be useful to inmate populations to improve their health status and fitness levels. A repeated measure design was used to evaluate the effects of two different training protocols on subjects in a state of detention, tested pre- and post-experimental protocol.Seventy-five male subjects were enrolled in the studyand randomly allocated to three groups: the cardiovascular plus resistance training protocol group (CRT (n = 25; mean age 30.9 ± 8.9 years,the high-intensity strength training protocol group (HIST (n = 25; mean age 33.9 ± 6.8 years, and a control group (C (n = 25; mean age 32.9 ± 8.9 years receiving no treatment. All subjects underwent a clinical assessmentandfitness tests. MANOVA revealed significant multivariate effects on group (p < 0.01 and group-training interaction (p < 0.05. CRT protocol resulted the most effective protocol to reach the best outcome in fitness tests. Both CRT and HIST protocols produced significant gains in the functional capacity (cardio-respiratory capacity and cardiovascular disease risk decrease of incarcerated males. The significant gains obtained in functional capacity reflect the great potential of supervised exercise interventions for improving the health status of incarcerated people.

  18. A randomized trial of peer coach and office staff support to reduce coronary heart disease risk in African-Americans with uncontrolled hypertension.

    Science.gov (United States)

    Turner, Barbara J; Hollenbeak, Christopher S; Liang, Yuanyuan; Pandit, Kavita; Joseph, Shelly; Weiner, Mark G

    2012-10-01

    Adopting features of the Chronic Care Model may reduce coronary heart disease risk and blood pressure in vulnerable populations. We evaluated a peer and practice team intervention on reduction in 4-year coronary heart disease risk and systolic blood pressure. A single blind, randomized, controlled trial in two adjacent urban university-affiliated primary care practices. Two hundred eighty African-American subjects aged 40 to 75 with uncontrolled hypertension. Three monthly calls from trained peer patients with well-controlled hypertension and, on alternate months, two practice staff visits to review a personalized 4-year heart disease risk calculator and slide shows about heart disease risks. All subjects received usual physician care and brochures about healthy cooking and heart disease. Change in 4-year coronary heart disease risk (primary) and change in systolic blood pressure, both assessed at 6 months. At baseline, the 136 intervention and 144 control subjects' mean 4-year coronary heart disease risk did not differ (intervention=5.8 % and control=6.4 %, P=0.39), and their mean systolic blood pressure was the same (140.5 mmHg, p=0.83). Endpoint data for coronary heart disease were obtained for 69 % of intervention and 82 % of control subjects. After multiple imputation for missing endpoint data, the reduction in risk among all 280 subjects favored the intervention, but was not statistically significant (difference -0.73 %, 95 % confidence interval: -1.54 % to 0.09 %, p=0.08). Among the 247 subjects with a systolic blood pressure endpoint (85 % of intervention and 91 % of control subjects), more intervention than control subjects achieved a >5 mmHg reduction (61 % versus 45 %, respectively, p=0.01). After multiple imputation, the absolute reduction in systolic blood pressure was also greater for the intervention group (difference -6.47 mmHg, 95 % confidence interval: -10.69 to -2.25, P=0.003). One patient died in each study arm. Peer patient and office

  19. Reduced plasma aldosterone concentrations in randomly selected patients with insulin-dependent diabetes mellitus.

    LENUS (Irish Health Repository)

    Cronin, C C

    2012-02-03

    Abnormalities of the renin-angiotensin system have been reported in patients with diabetes mellitus and with diabetic complications. In this study, plasma concentrations of prorenin, renin, and aldosterone were measured in a stratified random sample of 110 insulin-dependent (Type 1) diabetic patients attending our outpatient clinic. Fifty-four age- and sex-matched control subjects were also examined. Plasma prorenin concentration was higher in patients without complications than in control subjects when upright (geometric mean (95% confidence intervals (CI): 75.9 (55.0-105.6) vs 45.1 (31.6-64.3) mU I-1, p < 0.05). There was no difference in plasma prorenin concentration between patients without and with microalbuminuria and between patients without and with background retinopathy. Plasma renin concentration, both when supine and upright, was similar in control subjects, in patients without complications, and in patients with varying degrees of diabetic microangiopathy. Plasma aldosterone was suppressed in patients without complications in comparison to control subjects (74 (58-95) vs 167 (140-199) ng I-1, p < 0.001) and was also suppressed in patients with microvascular disease. Plasma potassium was significantly higher in patients than in control subjects (mean +\\/- standard deviation: 4.10 +\\/- 0.36 vs 3.89 +\\/- 0.26 mmol I-1; p < 0.001) and plasma sodium was significantly lower (138 +\\/- 4 vs 140 +\\/- 2 mmol I-1; p < 0.001). We conclude that plasma prorenin is not a useful early marker for diabetic microvascular disease. Despite apparently normal plasma renin concentrations, plasma aldosterone is suppressed in insulin-dependent diabetic patients.

  20. 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.

  1. Bio-accumulation of selected metals in African sharptooth catfish Clarias gariepinus from the lower Olifants River, Mpumalanga, South Africa

    Directory of Open Access Journals (Sweden)

    H.H. Du Preez

    1997-01-01

    Full Text Available The level of metal (Cr, Cu, Mn, Ni, Pb and Zn bio- accumulation in tissues (muscle, gill, kidney, liver and gonads and bile of the African catfish Clarias gariepinus, from the lower Olifants River was investigated. These metals were detected in all the tissues as well as in the bile, with the highest concentration found in either the gills, liver or gonadal tissue. The lowest concentration was usually detected in the muscle tissue. Although statistic comparisons revealed no significant differences between the localities, fish from the Selati River (Locality 1 generally had higher metal levels than fish from the localities along the Olifants River inside the Kruger National Park. The higher levels in the fish from the Selati River may be attributed to anthropogenic activities resulting in point and/or diffuse sources of metal pollution. These sources should be identified and reduced.

  2. Effectiveness of a selective, personality-targeted prevention program for adolescent alcohol use and misuse: a cluster randomized controlled trial.

    Science.gov (United States)

    Conrod, Patricia J; O'Leary-Barrett, Maeve; Newton, Nicola; Topper, Lauren; Castellanos-Ryan, Natalie; Mackie, Clare; Girard, Alain

    2013-03-01

    Selective school-based alcohol prevention programs targeting youth with personality risk factors for addiction and mental health problems have been found to reduce substance use and misuse in those with elevated personality profiles. To report 24-month outcomes of the Teacher-Delivered Personality-Targeted Interventions for Substance Misuse Trial (Adventure trial) in which school staff were trained to provide interventions to students with 1 of 4 high-risk (HR) profiles: anxiety sensitivity, hopelessness, impulsivity, and sensation seeking and to examine the indirect herd effects of this program on the broader low-risk (LR) population of students who were not selected for intervention. Cluster randomized controlled trial. Secondary schools in London, United Kingdom. A total of 1210 HR and 1433 LR students in the ninth grade (mean [SD] age, 13.7 [0.33] years). Schools were randomized to provide brief personality-targeted interventions to HR youth or treatment as usual (statutory drug education in class). Participants were assessed for drinking, binge drinking, and problem drinking before randomization and at 6-monthly intervals for 2 years. Two-part latent growth models indicated long-term effects of the intervention on drinking rates (β = -0.320, SE = 0.145, P = .03) and binge drinking rates (β = -0.400, SE = 0.179, P = .03) and growth in binge drinking (β = -0.716, SE = 0.274, P = .009) and problem drinking (β = -0.452, SE = 0.193, P = .02) for HR youth. The HR youth were also found to benefit from the interventions during the 24-month follow-up on drinking quantity (β = -0.098, SE = 0.047, P = .04), growth in drinking quantity (β = -0.176, SE = 0.073, P = .02), and growth in binge drinking frequency (β = -0.183, SE = 0.092, P = .047). Some herd effects in LR youth were observed, specifically on drinking rates (β = -0.259, SE = 0.132, P = .049) and growth of binge drinking (β = -0.244, SE = 0.073, P = .001), during the 24-month follow-up. Findings further

  3. Strategies used in the translation of fixed expressions in magazines: A comparison of selected texts with Afrikaans as source language and South African English as target language

    Directory of Open Access Journals (Sweden)

    Alan Murdoch

    2017-04-01

    Full Text Available This article will look at the translation of idioms and other types of fixed expressions from Afrikaans (the source language into South African English (the target language, from selected texts in Huisgenoot and You magazines from a study conducted over the 10-week period from 18 July 2013 to 19 September 2013. The article will start by looking at the difficulties in defining idioms and other types of fixed expressions and will draw on the work of Rosamund Moon for this. It then uses the strategies on the translation of idioms (and other types of fixed expressions in Mona Baker’s In Other Words to categorise a set of 70 such expressions according to the strategy used to translate them and concludes by looking at whether equivalence is obtained.

  4. Randomized pharmacokinetic evaluation of different rifabutin doses in African HIV- infected tuberculosis patients on lopinavir/ritonavir-based antiretroviral therapy.

    Science.gov (United States)

    Naiker, Suhashni; Connolly, Cathy; Wiesner, Lubbe; Kellerman, Tracey; Reddy, Tarylee; Harries, Anthony; McIlleron, Helen; Lienhardt, Christian; Pym, Alexander

    2014-11-19

    Pharmacokinetic interactions between rifampicin and protease inhibitors (PIs) complicate the management of HIV-associated tuberculosis. Rifabutin is an alternative rifamycin, for patients requiring PIs. Recently some international guidelines have recommended a higher dose of rifabutin (150 mg daily) in combination with boosted lopinavir (LPV/r), than the previous dose of rifabutin (150 mg three times weekly {tiw}). But there are limited pharmacokinetic data evaluating the higher dose of rifabutin in combination with LPV/r. Sub-optimal dosing can lead to acquired rifamycin resistance (ARR). The plasma concentration of 25-O-desacetylrifabutin (d-RBT), the metabolite of rifabutin, increases in the presence of PIs and may lead to toxicity. Sixteen patients with TB-HIV co-infection received rifabutin 300 mg QD in combination with tuberculosis chemotherapy (initially pyrazinamide, isoniazid and ethambutol then only isoniazid), and were then randomized to receive isoniazid and LPV/r based ART with rifabutin 150 mg tiw or rifabutin 150 mg daily. The rifabutin dose with ART was switched after 1 month. Serial rifabutin and d-RBT concentrations were measured after 4 weeks of each treatment. The median AUC0-48 and Cmax of rifabutin in patients taking 150 mg rifabutin tiw was significantly reduced compared to the other treatment arms. Geometric mean ratio (90% CI) for AUC0-48 and Cmax was 0.6 (0.5-0.7) and 0.5 (0.4-0.6) for RBT 150 mg tiw compared with RBT 300 mg and 0.4 (0.4-0.4) and 0.5 (0.5-0.6) for RBT 150 mg tiw compared with 150 mg daily. 86% of patients on the tiw rifabutin arm had an AUC0-24 ART, and grade 3 neutropenia (asymptomatic) was reported in 4 patients. These events were not associated with increases in rifabutin or metabolite concentrations. A daily 150 mg dose of rifabutin in combination with LPV/r safely maintained rifabutin plasma concentrations in line with those shown to prevent ARR. ClinicalTrials.gov Identifier: NCT00640887.

  5. Human rotavirus vaccine Rotarix™ provides protection against diverse circulating rotavirus strains in African infants: a randomized controlled trial

    Science.gov (United States)

    2012-01-01

    Background Rotaviruses are the most important cause of severe acute gastroenteritis worldwide in children rotavirus vaccine Rotarix™ significantly reduced severe rotavirus gastroenteritis episodes in a Phase III clinical trial conducted in infants in South Africa and Malawi. This paper examines rotavirus vaccine efficacy in preventing severe rotavirus gastroenteritis, during infancy, caused by the various G and P rotavirus types encountered during the first rotavirus-season. Methods Healthy infants aged 5–10 weeks were enrolled and randomized into three groups to receive either two (10 and 14 weeks) or three doses of Rotarix™ (together forming the pooled Rotarix™ group) or three doses of placebo at a 6,10,14-week schedule. Weekly home visits were conducted to identify gastroenteritis episodes. Rotaviruses were detected by ELISA and genotyped by RT-PCR and nucleotide sequencing. The percentage of infants with severe rotavirus gastroenteritis caused by the circulating G and P types from 2 weeks post-last dose until one year of age and the corresponding vaccine efficacy was calculated with 95% CI. Results Overall, 4939 infants were vaccinated and 4417 (pooled Rotarix™ = 2974; placebo = 1443) were included in the per protocol efficacy cohort. G1 wild-type was detected in 23 (1.6%) severe rotavirus gastroenteritis episodes from the placebo group. This was followed in order of detection by G12 (15 [1%] in placebo) and G8 types (15 [1%] in placebo). Vaccine efficacy against G1 wild-type, G12 and G8 types were 64.1% (95% CI: 29.9%; 82%), 51.5% (95% CI:-6.5%; 77.9%) and 64.4% (95% CI: 17.1%; 85.2%), respectively. Genotype P[8] was the predominant circulating P type and was detected in 38 (2.6%) severe rotavirus gastroenteritis cases in placebo group. The remaining circulating P types comprised of P[4] (20 [1.4%] in placebo) and P[6] (13 [0.9%] in placebo). Vaccine efficacy against P[8] was 59.1% (95% CI: 32.8%; 75.3%), P[4] was 70.9% (95% CI: 37

  6. Human rotavirus vaccine Rotarix™ provides protection against diverse circulating rotavirus strains in African infants: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Steele Andrew

    2012-09-01

    Full Text Available Abstract Background Rotaviruses are the most important cause of severe acute gastroenteritis worldwide in children Rotarix™ significantly reduced severe rotavirus gastroenteritis episodes in a Phase III clinical trial conducted in infants in South Africa and Malawi. This paper examines rotavirus vaccine efficacy in preventing severe rotavirus gastroenteritis, during infancy, caused by the various G and P rotavirus types encountered during the first rotavirus-season. Methods Healthy infants aged 5–10 weeks were enrolled and randomized into three groups to receive either two (10 and 14 weeks or three doses of Rotarix™ (together forming the pooled Rotarix™ group or three doses of placebo at a 6,10,14-week schedule. Weekly home visits were conducted to identify gastroenteritis episodes. Rotaviruses were detected by ELISA and genotyped by RT-PCR and nucleotide sequencing. The percentage of infants with severe rotavirus gastroenteritis caused by the circulating G and P types from 2 weeks post-last dose until one year of age and the corresponding vaccine efficacy was calculated with 95% CI. Results Overall, 4939 infants were vaccinated and 4417 (pooled Rotarix™ = 2974; placebo = 1443 were included in the per protocol efficacy cohort. G1 wild-type was detected in 23 (1.6% severe rotavirus gastroenteritis episodes from the placebo group. This was followed in order of detection by G12 (15 [1%] in placebo and G8 types (15 [1%] in placebo. Vaccine efficacy against G1 wild-type, G12 and G8 types were 64.1% (95% CI: 29.9%; 82%, 51.5% (95% CI:-6.5%; 77.9% and 64.4% (95% CI: 17.1%; 85.2%, respectively. Genotype P[8] was the predominant circulating P type and was detected in 38 (2.6% severe rotavirus gastroenteritis cases in placebo group. The remaining circulating P types comprised of P[4] (20 [1.4%] in placebo and P[6] (13 [0.9%] in placebo. Vaccine efficacy against P[8] was 59.1% (95% CI: 32.8%; 75.3%, P[4] was 70.9% (95% CI: 37.5%; 87

  7. Preference option randomized design (PORD) for comparative effectiveness research: Statistical power for testing comparative effect, preference effect, selection effect, intent-to-treat effect, and overall effect.

    Science.gov (United States)

    Heo, Moonseong; Meissner, Paul; Litwin, Alain H; Arnsten, Julia H; McKee, M Diane; Karasz, Alison; McKinley, Paula; Rehm, Colin D; Chambers, Earle C; Yeh, Ming-Chin; Wylie-Rosett, Judith

    2017-01-01

    Comparative effectiveness research trials in real-world settings may require participants to choose between preferred intervention options. A randomized clinical trial with parallel experimental and control arms is straightforward and regarded as a gold standard design, but by design it forces and anticipates the participants to comply with a randomly assigned intervention regardless of their preference. Therefore, the randomized clinical trial may impose impractical limitations when planning comparative effectiveness research trials. To accommodate participants' preference if they are expressed, and to maintain randomization, we propose an alternative design that allows participants' preference after randomization, which we call a "preference option randomized design (PORD)". In contrast to other preference designs, which ask whether or not participants consent to the assigned intervention after randomization, the crucial feature of preference option randomized design is its unique informed consent process before randomization. Specifically, the preference option randomized design consent process informs participants that they can opt out and switch to the other intervention only if after randomization they actively express the desire to do so. Participants who do not independently express explicit alternate preference or assent to the randomly assigned intervention are considered to not have an alternate preference. In sum, preference option randomized design intends to maximize retention, minimize possibility of forced assignment for any participants, and to maintain randomization by allowing participants with no or equal preference to represent random assignments. This design scheme enables to define five effects that are interconnected with each other through common design parameters-comparative, preference, selection, intent-to-treat, and overall/as-treated-to collectively guide decision making between interventions. Statistical power functions for testing

  8. Single-chain lipopeptide vaccines for the induction of virus-specific cytotoxic T cell responses in randomly selected populations.

    Science.gov (United States)

    Gras-Masse, H

    2001-12-01

    Effective vaccine development is now taking advantage of the rapidly accumulating information concerning the molecular basis of a protective immune response. Analysts and medicinal chemists have joined forces with immunologists and taken up the clear challenge of identifying immunologically active structural elements and synthesizing them in pure, reproducible forms. Current literature reveals the growing interest for extremely reductionist approaches aiming at producing totally synthetic vaccines that would be fully defined at the molecular level and particularly safe. The sequential information contained in these formulations tends to be minimized to those epitopes which elicit neutralizing antibodies, or cell-mediated responses. In the following review, we describe some of our results in developing fully synthetic, clinically acceptable lipopeptide vaccines for inducing cytotoxic T lymphocytes (CTL) responses in randomly selected populations.

  9. Selecting Optimal Random Forest Predictive Models: A Case Study on Predicting the Spatial Distribution of Seabed Hardness

    Science.gov (United States)

    Li, Jin; Tran, Maggie; Siwabessy, Justy

    2016-01-01

    Spatially continuous predictions of seabed hardness are important baseline environmental information for sustainable management of Australia’s marine jurisdiction. Seabed hardness is often inferred from multibeam backscatter data with unknown accuracy and can be inferred from underwater video footage at limited locations. In this study, we classified the seabed into four classes based on two new seabed hardness classification schemes (i.e., hard90 and hard70). We developed optimal predictive models to predict seabed hardness using random forest (RF) based on the point data of hardness classes and spatially continuous multibeam data. Five feature selection (FS) methods that are variable importance (VI), averaged variable importance (AVI), knowledge informed AVI (KIAVI), Boruta and regularized RF (RRF) were tested based on predictive accuracy. Effects of highly correlated, important and unimportant predictors on the accuracy of RF predictive models were examined. Finally, spatial predictions generated using the most accurate models were visually examined and analysed. This study confirmed that: 1) hard90 and hard70 are effective seabed hardness classification schemes; 2) seabed hardness of four classes can be predicted with a high degree of accuracy; 3) the typical approach used to pre-select predictive variables by excluding highly correlated variables needs to be re-examined; 4) the identification of the important and unimportant predictors provides useful guidelines for further improving predictive models; 5) FS methods select the most accurate predictive model(s) instead of the most parsimonious ones, and AVI and Boruta are recommended for future studies; and 6) RF is an effective modelling method with high predictive accuracy for multi-level categorical data and can be applied to ‘small p and large n’ problems in environmental sciences. Additionally, automated computational programs for AVI need to be developed to increase its computational efficiency and

  10. Selecting Optimal Random Forest Predictive Models: A Case Study on Predicting the Spatial Distribution of Seabed Hardness.

    Directory of Open Access Journals (Sweden)

    Jin Li

    Full Text Available Spatially continuous predictions of seabed hardness are important baseline environmental information for sustainable management of Australia's marine jurisdiction. Seabed hardness is often inferred from multibeam backscatter data with unknown accuracy and can be inferred from underwater video footage at limited locations. In this study, we classified the seabed into four classes based on two new seabed hardness classification schemes (i.e., hard90 and hard70. We developed optimal predictive models to predict seabed hardness using random forest (RF based on the point data of hardness classes and spatially continuous multibeam data. Five feature selection (FS methods that are variable importance (VI, averaged variable importance (AVI, knowledge informed AVI (KIAVI, Boruta and regularized RF (RRF were tested based on predictive accuracy. Effects of highly correlated, important and unimportant predictors on the accuracy of RF predictive models were examined. Finally, spatial predictions generated using the most accurate models were visually examined and analysed. This study confirmed that: 1 hard90 and hard70 are effective seabed hardness classification schemes; 2 seabed hardness of four classes can be predicted with a high degree of accuracy; 3 the typical approach used to pre-select predictive variables by excluding highly correlated variables needs to be re-examined; 4 the identification of the important and unimportant predictors provides useful guidelines for further improving predictive models; 5 FS methods select the most accurate predictive model(s instead of the most parsimonious ones, and AVI and Boruta are recommended for future studies; and 6 RF is an effective modelling method with high predictive accuracy for multi-level categorical data and can be applied to 'small p and large n' problems in environmental sciences. Additionally, automated computational programs for AVI need to be developed to increase its computational efficiency and

  11. Using IT to improve access, communication, and asthma in African American and Hispanic/Latino Adults: Rationale, design, and methods of a randomized controlled trial.

    Science.gov (United States)

    Apter, Andrea J; Bryant-Stephens, Tyra; Morales, Knashawn H; Wan, Fei; Hardy, Sharmaine; Reed-Wells, Shakira; Dominguez, Maria; Gonzalez, Rodalyn; Mak, NaDea; Nardi, Alyssa; Park, Hami; Howell, John T; Localio, Russell

    2015-09-01

    Asthma morbidity is high among inner-city minority adults. Improving access to care and patient-provider communication are believed to be essential for improving outcomes. Access and communication in turn increasingly rely on information technology including features of the Electronic Health Record. Its patient portal offers web-based communication with providers and practices. How patients with limited resources and educational opportunities can benefit from this portal is unclear. In contrast, home visits by community health workers (CHWs) have improved access to care for asthmatic children and promoted caretaker-clinician communication. We describe the planning, design, and methodology of an ongoing randomized controlled trial for 300 adults, predominantly African American and Hispanic/Latino, with uncontrolled asthma recruited from low income urban neighborhoods who are directed to the most convenient internet access and taught to use the portal, with and without home visits from a CHW. The study 1) compares the effects of the 1-year interventions on asthma outcomes (improved asthma control, quality of life; fewer ED visits and hospitalizations for asthma or any cause), 2) evaluates whether communication (portal use) and access (appointments made/kept) mediate the interventions' effects on asthma outcomes, and 3) investigates effect modification by literacy level, primary language, and convenience of internet access. In home visits, CHWs 1) train patients to competency in portal use, 2) enhance care coordination, 3) communicate the complex social circumstances of patients' lives to providers, and 4) compensate for differences in patients' health literacy skills. The practical challenges to design and implementation in the targeted population are presented. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Modeling the Causal Role of DNA Methylation in the Association Between Cigarette Smoking and Inflammation in African Americans: A 2-Step Epigenetic Mendelian Randomization Study.

    Science.gov (United States)

    Jhun, Min A; Smith, Jennifer A; Ware, Erin B; Kardia, Sharon L R; Mosley, Thomas H; Turner, Stephen T; Peyser, Patricia A; Park, Sung Kyun

    2017-11-15

    The association between cigarette smoking and inflammation is well known. However, the biological mechanisms behind the association are not fully understood, particularly the role of DNA methylation, which is known to be affected by smoking. Using 2-step epigenetic Mendelian randomization, we investigated the role of DNA methylation in the association between cigarette smoking and inflammation. In 822 African Americans from the Genetic Epidemiology Network of Arteriopathy, phase 2 (Jackson, Mississippi; 2000-2005), study population, we examined the association of cigarette smoking with DNA methylation using single nucleotide polymorphisms identified in previous genome-wide association studies of cigarette smoking. We then investigated the association of DNA methylation with levels of inflammatory markers using cis-methylation quantitative trait loci single nucleotide polymorphisms. We found that current smoking status was associated with the DNA methylation levels (M values) of cg03636183 in the coagulation factor II (thrombin) receptor-like 3 gene (F2RL3) (M = -0.64, 95% confidence interval (CI): -0.84, -0.45) and of cg19859270 in the G protein-coupled receptor 15 gene (GPR15) (M = -0.21, 95% CI: -0.27, -0.15). The DNA methylation levels of cg03636183 in F2RL3 were associated with interleukin-18 concentration (-0.11 pg/mL, 95% CI: -0.19, -0.04). These combined negative effects suggest that cigarette smoking increases interleukin-18 levels through the decrease in DNA methylation levels of cg03636183 in F2RL3. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Women's empowerment and male involvement in antenatal care: analyses of Demographic and Health Surveys (DHS) in selected African countries.

    Science.gov (United States)

    Jennings, Larissa; Na, Muzi; Cherewick, Megan; Hindin, Michelle; Mullany, Britta; Ahmed, Saifuddin

    2014-08-30

    Increasing women's status and male involvement are important strategies in reducing preventable maternal morbidity and mortality. While efforts to both empower women and engage men in maternal health care-seeking can work synergistically, in practice they may result in opposing processes and outcomes. This study examines whether a woman's empowerment status, in sum and across economic, socio-familial, and legal dimensions, is associated with male partner accompaniment to antenatal care (ANC). Women's empowerment was measured based on the sum of nine empowerment items in the 2010-2011 Demographic and Health Surveys in eight sub-Saharan African countries: Burkina Faso (n = 2,490), Burundi (n = 1,042), Malawi (n = 1,353), Mozambique (n = 414), Rwanda (n = 1,211), Senegal (n = 505), Uganda (n = 428) and Zimbabwe (n = 459). In cross-sectional analyses, bivariate and multivariable logistic regressions models were used to examine the odds of male partner accompaniment to ANC between women with above-average versus below-average composite and dimensional empowerment scores. In the majority of countries, male accompaniment to ANC was not uncommon. However, findings were mixed. Positive associations in women's composite empowerment and male involvement were observed in Burkina Faso (OR = 1.27, 95% CI: 1.08, 1.50) and Uganda (OR = 1.53, 95% CI: 1.00-2.35), and in the economic empowerment dimension in Burkina Faso (OR = 1.24, 95% CI: 1.05-1.47). In Malawi, significant negative associations were observed in the odds of male accompaniment to ANC and women's composite (OR = 0.77, 95% CI: 0.62-0.97) and economic empowerment scores (OR = 0.75, 95% CI: 0.59-0.94). No significant differences were observed in Burundi, Mozambique, Rwanda, Senegal, or Zimbabwe. Women's empowerment can be positively or negatively associated with male antenatal accompaniment. Male involvement efforts may benefit from empowerment initiatives that promote women's participation in social and economic spheres

  14. Randomized trial of switching from prescribed non-selective non-steroidal anti-inflammatory drugs to prescribed celecoxib

    DEFF Research Database (Denmark)

    Macdonald, Thomas M; Hawkey, Chris J; Ford, Ian

    2017-01-01

    BACKGROUND: Selective cyclooxygenase-2 inhibitors and conventional non-selective non-steroidal anti-inflammatory drugs (nsNSAIDs) have been associated with adverse cardiovascular (CV) effects. We compared the CV safety of switching to celecoxib vs. continuing nsNSAID therapy in a European setting....... METHOD: Patients aged 60 years and over with osteoarthritis or rheumatoid arthritis, free from established CV disease and taking chronic prescribed nsNSAIDs, were randomized to switch to celecoxib or to continue their previous nsNSAID. The primary endpoint was hospitalization for non-fatal myocardial...... expected developed an on-treatment (OT) primary CV event and the rate was similar for celecoxib, 0.95 per 100 patient-years, and nsNSAIDs, 0.86 per 100 patient-years (HR = 1.12, 95% confidence interval, 0.81-1.55; P = 0.50). Comparable intention-to-treat (ITT) rates were 1.14 per 100 patient...

  15. Dual Use of Cigarettes and Smokeless Tobacco among South African Adolescents

    Science.gov (United States)

    Rantao, Masego; Ayo-Yusuf, Olalekan A.

    2012-01-01

    Objectives: To determine factors associated with dual use of tobacco products in a population of black South African adolescents. Methods: Data were obtained from a self-administered questionnaire completed by a representative sample of grade 8 students from 21 randomly selected secondary state schools in the Limpopo Province, South Africa (n =…

  16. In vitro characterization of representative clinical South African Staphylococcus aureus isolates from various clonal lineages

    NARCIS (Netherlands)

    Oosthuysen, W F; Orth, H; Lombard, C. J.; Sinha, B; Wasserman, E

    Data concerning the virulence and pathogenesis of South African strains of Staphylococcus aureus are limited. We investigated host-pathogen interactions of randomly selected clinical S. aureus isolates representing various clones. We characterized the ability of isolates to adhere to fibronectin,

  17. Knowledge about HIV and AIDS among Young South Africans in the Capricorn District, Limpopo Province

    Science.gov (United States)

    Melwa, Irene T.; Oduntan, Olalekan A.

    2012-01-01

    Objective: To assess the basic knowledge about HIV and AIDS among young South Africans in the Capricorn District of Limpopo Province, South Africa. Design: A questionnaire-based cohort study, involving data collection from senior high school students. Setting: Randomly selected high schools in the Capricorn District, Limpopo Province, South…

  18. K-Ras(G12D)-selective inhibitory peptides generated by random peptide T7 phage display technology.

    Science.gov (United States)

    Sakamoto, Kotaro; Kamada, Yusuke; Sameshima, Tomoya; Yaguchi, Masahiro; Niida, Ayumu; Sasaki, Shigekazu; Miwa, Masanori; Ohkubo, Shoichi; Sakamoto, Jun-Ichi; Kamaura, Masahiro; Cho, Nobuo; Tani, Akiyoshi

    2017-03-11

    Amino-acid mutations of Gly 12 (e.g. G12D, G12V, G12C) of V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (K-Ras), the most promising drug target in cancer therapy, are major growth drivers in various cancers. Although over 30 years have passed since the discovery of these mutations in most cancer patients, effective mutated K-Ras inhibitors have not been marketed. Here, we report novel and selective inhibitory peptides to K-Ras(G12D). We screened random peptide libraries displayed on T7 phage against purified recombinant K-Ras(G12D), with thorough subtraction of phages bound to wild-type K-Ras, and obtained KRpep-2 (Ac-RRCPLYISYDPVCRR-NH 2 ) as a consensus sequence. KRpep-2 showed more than 10-fold binding- and inhibition-selectivity to K-Ras(G12D), both in SPR analysis and GDP/GTP exchange enzyme assay. K D and IC 50 values were 51 and 8.9 nM, respectively. After subsequent sequence optimization, we successfully generated KRpep-2d (Ac-RRRRCPLYISYDPVCRRRR-NH 2 ) that inhibited enzyme activity of K-Ras(G12D) with IC 50  = 1.6 nM and significantly suppressed ERK-phosphorylation, downstream of K-Ras(G12D), along with A427 cancer cell proliferation at 30 μM peptide concentration. To our knowledge, this is the first report of a K-Ras(G12D)-selective inhibitor, contributing to the development and study of K-Ras(G12D)-targeting drugs. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. 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.

  20. 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.

  1. Genomic Footprints of Selective Sweeps from Metabolic Resistance to Pyrethroids in African Malaria Vectors Are Driven by Scale up of Insecticide-Based Vector Control.

    Science.gov (United States)

    Barnes, Kayla G; Weedall, Gareth D; Ndula, Miranda; Irving, Helen; Mzihalowa, Themba; Hemingway, Janet; Wondji, Charles S

    2017-02-01

    Insecticide resistance in mosquito populations threatens recent successes in malaria prevention. Elucidating patterns of genetic structure in malaria vectors to predict the speed and direction of the spread of resistance is essential to get ahead of the 'resistance curve' and to avert a public health catastrophe. Here, applying a combination of microsatellite analysis, whole genome sequencing and targeted sequencing of a resistance locus, we elucidated the continent-wide population structure of a major African malaria vector, Anopheles funestus. We identified a major selective sweep in a genomic region controlling cytochrome P450-based metabolic resistance conferring high resistance to pyrethroids. This selective sweep occurred since 2002, likely as a direct consequence of scaled up vector control as revealed by whole genome and fine-scale sequencing of pre- and post-intervention populations. Fine-scaled analysis of the pyrethroid resistance locus revealed that a resistance-associated allele of the cytochrome P450 monooxygenase CYP6P9a has swept through southern Africa to near fixation, in contrast to high polymorphism levels before interventions, conferring high levels of pyrethroid resistance linked to control failure. Population structure analysis revealed a barrier to gene flow between southern Africa and other areas, which may prevent or slow the spread of the southern mechanism of pyrethroid resistance to other regions. By identifying a genetic signature of pyrethroid-based interventions, we have demonstrated the intense selective pressure that control interventions exert on mosquito populations. If this level of selection and spread of resistance continues unabated, our ability to control malaria with current interventions will be compromised.

  2. A tight balance between natural selection and gene flow in a southern African arid-zone endemic bird.

    Science.gov (United States)

    Ribeiro, Ångela M; Lloyd, Penn; Bowie, Rauri C K

    2011-12-01

    Gene flow is traditionally thought to be antagonistic to population differentiation and local adaptation. However, recent studies have demonstrated that local adaptation can proceed provided that selection is greater than the homogenizing effects of gene flow. We extend these initial studies by combining ecology (climate), phenotype (body size), physiological genetics (oxidative phosphorylation genes), and neutral loci (nuclear microsatellites and introns) to test whether selection can counter-balance gene flow and hence promote local adaptation in a bird whose distribution spans an aridity gradient. Our results show that the Karoo scrub-robin's climatic niche is spatially structured, providing the potential for local adaptation to develop. We found remarkably discordant patterns of divergence among mtDNA, morphology, and neutral loci. For the mitochondrial genes, two amino acid replacements, strong population structure and reduced gene flow were associated with the environmental gradient separating western coastal sites from the interior of southern Africa. In contrast, morphology and the neutral loci exhibited variation independent of environmental variables, and revealed extensive levels of gene flow across the aridity gradient, 50 times larger than the estimates for mitochondrial genes. Together, our results suggest that selective pressures on physiology, mediated by the mitochondrial genome, may well be a common mechanism for facilitating local adaptation to new climatic conditions. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

  3. Habitat selection by African buffalo (Syncerus caffer in response to landscape-level fluctuations in water availability on two temporal scales.

    Directory of Open Access Journals (Sweden)

    Emily Bennitt

    Full Text Available Seasonal fluctuations in water availability cause predictable changes in the profitability of habitats in tropical ecosystems, and animals evolve adaptive behavioural and spatial responses to these fluctuations. However, stochastic changes in the distribution and abundance of surface water between years can alter resource availability at a landscape scale, causing shifts in animal behaviour. In the Okavango Delta, Botswana, a flood-pulsed ecosystem, the volume of water entering the system doubled between 2008 and 2009, creating a sudden change in the landscape. We used African buffalo (Syncerus caffer to test the hypotheses that seasonal habitat selection would be related to water availability, that increased floodwater levels would decrease forage abundance and affect habitat selection, and that this would decrease buffalo resting time, reduce reproductive success and decrease body condition. Buffalo selected contrasting seasonal habitats, using habitats far from permanent water during the rainy season and seasonally-flooded habitats close to permanent water during the early and late flood seasons. The 2009 water increase reduced forage availability in seasonally-flooded habitats, removing a resource buffer used by the buffalo during the late flood season, when resources were most limited. In response, buffalo used drier habitats in 2009, although there was no significant change in the time spent moving or resting, or daily distance moved. While their reproductive success decreased in 2009, body condition increased. A protracted period of high water levels could prove detrimental to herbivores, especially to smaller-bodied species that require high quality forage. Stochastic annual fluctuations in water levels, predicted to increase as a result of anthropogenically-induced climate change, are likely to have substantial impacts on the functioning of water-driven tropical ecosystems, affecting environmental conditions within protected areas

  4. Selectivity of Chemoresistive Sensors Made of Chemically Functionalized Carbon Nanotube Random Networks for Volatile Organic Compounds (VOC

    Directory of Open Access Journals (Sweden)

    Jean-François Feller

    2014-01-01

    Full Text Available Different grades of chemically functionalized carbon nanotubes (CNT have been processed by spraying layer-by-layer (sLbL to obtain an array of chemoresistive transducers for volatile organic compound (VOC detection. The sLbL process led to random networks of CNT less conductive, but more sensitive to vapors than filtration under vacuum (bucky papers. Shorter CNT were also found to be more sensitive due to the less entangled and more easily disconnectable conducting networks they are making. Chemical functionalization of the CNT’ surface is changing their selectivity towards VOC, which makes it possible to easily discriminate methanol, chloroform and tetrahydrofuran (THF from toluene vapors after the assembly of CNT transducers into an array to make an e-nose. Interestingly, the amplitude of the CNT transducers’ responses can be enhanced by a factor of five (methanol to 100 (chloroform by dispersing them into a polymer matrix, such as poly(styrene (PS, poly(carbonate (PC or poly(methyl methacrylate (PMMA. COOH functionalization of CNT was found to penalize their dispersion in polymers and to decrease the sensors’ sensitivity. The resulting conductive polymer nanocomposites (CPCs not only allow for a more easy tuning of the sensors’ selectivity by changing the chemical nature of the matrix, but they also allow them to adjust their sensitivity by changing the average gap between CNT (acting on quantum tunneling in the CNT network. Quantum resistive sensors (QRSs appear promising for environmental monitoring and anticipated disease diagnostics that are both based on VOC analysis.

  5. Optimal Subset Selection of Time-Series MODIS Images and Sample Data Transfer with Random Forests for Supervised Classification Modelling

    Directory of Open Access Journals (Sweden)

    Fuqun Zhou

    2016-10-01

    Full Text Available Nowadays, various time-series Earth Observation data with multiple bands are freely available, such as Moderate Resolution Imaging Spectroradiometer (MODIS datasets including 8-day composites from NASA, and 10-day composites from the Canada Centre for Remote Sensing (CCRS. It is challenging to efficiently use these time-series MODIS datasets for long-term environmental monitoring due to their vast volume and information redundancy. This challenge will be greater when Sentinel 2–3 data become available. Another challenge that researchers face is the lack of in-situ data for supervised modelling, especially for time-series data analysis. In this study, we attempt to tackle the two important issues with a case study of land cover mapping using CCRS 10-day MODIS composites with the help of Random Forests’ features: variable importance, outlier identification. The variable importance feature is used to analyze and select optimal subsets of time-series MODIS imagery for efficient land cover mapping, and the outlier identification feature is utilized for transferring sample data available from one year to an adjacent year for supervised classification modelling. The results of the case study of agricultural land cover classification at a regional scale show that using only about a half of the variables we can achieve land cover classification accuracy close to that generated using the full dataset. The proposed simple but effective solution of sample transferring could make supervised modelling possible for applications lacking sample data.

  6. Biased random key genetic algorithm with insertion and gender selection for capacitated vehicle routing problem with time windows

    Science.gov (United States)

    Rochman, Auliya Noor; Prasetyo, Hari; Nugroho, Munajat Tri

    2017-06-01

    Vehicle Routing Problem (VRP) often occurs when the manufacturers need to distribute their product to some customers/outlets. The distribution process is typically restricted by the capacity of the vehicle and the working hours at the distributor. This type of VRP is also known as Capacitated Vehicle Routing Problem with Time Windows (CVRPTW). A Biased Random Key Genetic Algorithm (BRKGA) was designed and coded in MATLAB to solve the CVRPTW case of soft drink distribution. The standard BRKGA was then modified by applying chromosome insertion into the initial population and defining chromosome gender for parent undergoing crossover operation. The performance of the established algorithms was then compared to a heuristic procedure for solving a soft drink distribution. Some findings are revealed (1) the total distribution cost of BRKGA with insertion (BRKGA-I) results in a cost saving of 39% compared to the total cost of heuristic method, (2) BRKGA with the gender selection (BRKGA-GS) could further improve the performance of the heuristic method. However, the BRKGA-GS tends to yield worse results compared to that obtained from the standard BRKGA.

  7. Sequence-Based Prediction of RNA-Binding Proteins Using Random Forest with Minimum Redundancy Maximum Relevance Feature Selection

    Directory of Open Access Journals (Sweden)

    Xin Ma

    2015-01-01

    Full Text Available The prediction of RNA-binding proteins is one of the most challenging problems in computation biology. Although some studies have investigated this problem, the accuracy of prediction is still not sufficient. In this study, a highly accurate method was developed to predict RNA-binding proteins from amino acid sequences using random forests with the minimum redundancy maximum relevance (mRMR method, followed by incremental feature selection (IFS. We incorporated features of conjoint triad features and three novel features: binding propensity (BP, nonbinding propensity (NBP, and evolutionary information combined with physicochemical properties (EIPP. The results showed that these novel features have important roles in improving the performance of the predictor. Using the mRMR-IFS method, our predictor achieved the best performance (86.62% accuracy and 0.737 Matthews correlation coefficient. High prediction accuracy and successful prediction performance suggested that our method can be a useful approach to identify RNA-binding proteins from sequence information.

  8. A preliminary investigation of the jack-bean urease inhibition by randomly selected traditionally used herbal medicine.

    Science.gov (United States)

    Biglar, Mahmood; Soltani, Khadijeh; Nabati, Farzaneh; Bazl, Roya; Mojab, Faraz; Amanlou, Massoud

    2012-01-01

    Helicobacter pylori (H. pylori) infection leads to different clinical and pathological outcomes in humans, including chronic gastritis, peptic ulcer disease and gastric neoplasia and even gastric cancer and its eradiation dependst upon multi-drug therapy. The most effective therapy is still unknown and prompts people to make great efforts to find better and more modern natural or synthetic anti-H. pylori agents. In this report 21 randomly selected herbal methanolic extracts were evaluated for their effect on inhibition of Jack-bean urease using the indophenol method as described by Weatherburn. The inhibition potency was measured by UV spectroscopy technique at 630 nm which attributes to released ammonium. Among these extracts, five showed potent inhibitory activities with IC50 ranges of 18-35 μg/mL. These plants are Matricaria disciforme (IC50:35 μg/mL), Nasturtium officinale (IC50:18 μg/mL), Punica granatum (IC50:30 μg/mL), Camelia sinensis (IC50:35 μg/mL), Citrus aurantifolia (IC50:28 μg/mL).

  9. A brief, web-based personalized feedback selective intervention for college student marijuana use: a randomized clinical trial.

    Science.gov (United States)

    Lee, Christine M; Neighbors, Clayton; Kilmer, Jason R; Larimer, Mary E

    2010-06-01

    Despite clear need, brief web-based interventions for marijuana-using college students have not been evaluated in the literature. The current study was designed to evaluate a brief, web-based personalized feedback intervention for at-risk marijuana users transitioning to college. All entering first-year students were invited to complete a brief questionnaire. Participants meeting criteria completed a baseline assessment (N = 341) and were randomly assigned to web-based personalized feedback or assessment-only control conditions. Participants completed 3-month (95.0%) and 6-month (94.4%) follow-up assessments. Results indicated that although there was no overall intervention effect, moderator analyses found promising effects for those with a family history of drug problems and, to a smaller extent, students who were higher in contemplation of changing marijuana use at baseline. Implications of these findings for selective intervention of college marijuana use and web-based interventions in general are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  10. Optimal Subset Selection of Time-Series MODIS Images and Sample Data Transfer with Random Forests for Supervised Classification Modelling.

    Science.gov (United States)

    Zhou, Fuqun; Zhang, Aining

    2016-10-25

    Nowadays, various time-series Earth Observation data with multiple bands are freely available, such as Moderate Resolution Imaging Spectroradiometer (MODIS) datasets including 8-day composites from NASA, and 10-day composites from the Canada Centre for Remote Sensing (CCRS). It is challenging to efficiently use these time-series MODIS datasets for long-term environmental monitoring due to their vast volume and information redundancy. This challenge will be greater when Sentinel 2-3 data become available. Another challenge that researchers face is the lack of in-situ data for supervised modelling, especially for time-series data analysis. In this study, we attempt to tackle the two important issues with a case study of land cover mapping using CCRS 10-day MODIS composites with the help of Random Forests' features: variable importance, outlier identification. The variable importance feature is used to analyze and select optimal subsets of time-series MODIS imagery for efficient land cover mapping, and the outlier identification feature is utilized for transferring sample data available from one year to an adjacent year for supervised classification modelling. The results of the case study of agricultural land cover classification at a regional scale show that using only about a half of the variables we can achieve land cover classification accuracy close to that generated using the full dataset. The proposed simple but effective solution of sample transferring could make supervised modelling possible for applications lacking sample data.

  11. Selective non-operative management of abdominal stab wounds is a safe and cost effective strategy: A South African experience.

    Science.gov (United States)

    Dayananda, Kss; Kong, V Y; Bruce, J L; Oosthuizen, G V; Laing, G L; Clarke, D L

    2017-07-01

    INTRODUCTION Selective non-operative management (SNOM) of abdominal stab wounds is well established in South Africa. SNOM reduces the morbidity associated with negative laparotomies while being safe. Despite steady advances in technology (including laparoscopy, computed tomography [CT] and point-of-care sonography), our approach has remained clinically driven. Assessments of financial implications are limited in the literature. The aim of this study was to review isolated penetrating abdominal trauma and analyse associated incurred expenses. METHODS Patients data across the Pietermaritzburg Metropolitan Trauma Service (PMTS) are captured prospectively into the regional electronic trauma registry. A bottom-up microcosting technique produced estimated average costs for our defined clinical protocols. RESULTS Between January 2012 and April 2015, 501 patients were treated for an isolated abdominal stab wound. Over one third (38%) were managed successfully with SNOM, 5% underwent a negative laparotomy and over half (57%) required a therapeutic laparotomy. Over five years, the PMTS can expect to spend a minimum of ZAR 20,479,800 (GBP 1,246,840) for isolated penetrating abdominal stab wounds alone. CONCLUSIONS Provided a stringent policy is followed, in carefully selected patients, SNOM is effective in detecting those who require further intervention. It minimises the risks associated with unnecessary surgical interventions. SNOM will continue to be clinically driven and promulgated in our environment.

  12. Women's Education and Health Inequalities in Under-Five Mortality in Selected Sub-Saharan African Countries, 1990-2015.

    Directory of Open Access Journals (Sweden)

    Aristide Romaric Bado

    Full Text Available The aim of the study was to analyse trends in the relationship between mother's educational level and mortality of children under the year of five in Sub-Saharan Africa, from 1990 to 2015.Data used in this study came from different waves of Demographic and Health Surveys (DHS of Sub-Saharan countries. Logistic regression and Buis's decomposition method were used to explore the effect of mother's educational level on the mortality of children under five years.Although the results of our study in the selected countries show that under-five mortality rates of children born to mothers without formal education are higher than the mortality rates of children of educated mothers, it appears that differences in mortality were reduced over the past two decades. In selected countries for our study, we noticed a significant decline in mortality among children of non-educated mothers compared to the decrease in mortality rates among children of educated mothers during the period of 1990-2010. The results show that the decline in mortality of children under five years was much higher among the children born to mothers who have never received formal education-112 points drop in Malawi, over 80 in Zambia and Zimbabwe, 65 points in Burkina Faso, 56 in Congo, 43 in Namibia, 27 in Guinea, Cameroon, and 22 to 15 in Niger. However, we noted a variation in results among the countries selected for the study-in Burkina Faso (OR = 0.7, in Cameroon (OR = 0.8, in Guinea (OR = 0.8 and Niger (OR = 0.8. It is normally observed that children of mothers with 0-6 years of education are about 20% more likely to survive until their fifth year compared to children of mothers who have not been to school. Conversely, the results did not reveal significant differences between the under-five deaths of children born to non-educated mothers and children of low-level educated mothers in Congo, Malawi and Namibia.The decline in under-five mortality rates, during last two decades, can be

  13. Enumeration of Escherichia coli cells on chicken carcasses as a potential measure of microbial process control in a random selection of slaughter establishments in the United States

    Science.gov (United States)

    The purpose of this study was to evaluate whether the measurement of Escherichia coli levels at two points during the chicken slaughter process has utility as a measure of quality control. A one year long survey was conducted during 2004 and 2005 in 20 randomly selected United States chicken slaught...

  14. Impact of amoxicillin therapy on resistance selection in patients with community-acquired lower respiratory tract infections : A randomized, placebo-controlled study

    NARCIS (Netherlands)

    Malhotra-Kumar, Surbhi; Van Heirstraeten, Liesbet; Coenen, Samuel; Lammens, Christine; Adriaenssens, Niels; Kowalczyk, Anna; Godycki-Cwirko, Maciek; Bielicka, Zuzana; Hupkova, Helena; Lannering, Christina; Mölstad, Sigvard; Fernandez-Vandellos, Patricia; Torres, Antoni; Parizel, Maxim; Ieven, Margareta; Butler, Chris C.; Verheij, Theo; Little, Paul; Goossens, Hermanon; Frimodt-Møller, Niels; Bruno, Pascale; Hering, Iris; Lemiengre, Marieke; Loens, Katherine; Malmvall, Bo Eric; Muras, Magdalena; Romano, Nuria Sanchez; Prat, Matteu Serra; Svab, Igor; Swain, Jackie; Tarsia, Paolo; Leus, Frank; Veen, Robert; Worby, Tricia

    2016-01-01

    Objectives: To determine the effect of amoxicillin treatment on resistance selection in patients with community-acquired lower respiratory tract infections in a randomized, placebo-controlled trial. Methods: Patients were prescribed amoxicillin 1 g, three times daily (n = 52) or placebo (n = 50) for

  15. The Long-Term Effectiveness of a Selective, Personality-Targeted Prevention Program in Reducing Alcohol Use and Related Harms: A Cluster Randomized Controlled Trial

    Science.gov (United States)

    Newton, Nicola C.; Conrod, Patricia J.; Slade, Tim; Carragher, Natacha; Champion, Katrina E.; Barrett, Emma L.; Kelly, Erin V.; Nair, Natasha K.; Stapinski, Lexine; Teesson, Maree

    2016-01-01

    Background: This study investigated the long-term effectiveness of Preventure, a selective personality-targeted prevention program, in reducing the uptake of alcohol, harmful use of alcohol, and alcohol-related harms over a 3-year period. Methods: A cluster randomized controlled trial was conducted to assess the effectiveness of Preventure.…

  16. Are Africans, Europeans, and Asians different "races"? A guided-inquiry lab for introducing undergraduate students to genetic diversity and preparing them to study natural selection.

    Science.gov (United States)

    Kalinowski, Steven T; Andrews, Tessa M; Leonard, Mary J; Snodgrass, Meagan

    2012-01-01

    Many students do not recognize that individual organisms within populations vary, and this may make it difficult for them to recognize the essential role variation plays in natural selection. Also, many students have weak scientific reasoning skills, and this makes it difficult for them to recognize misconceptions they might have. This paper describes a 2-h laboratory for college students that introduces them to genetic diversity and gives them practice using hypothetico-deductive reasoning. In brief, the lab presents students with DNA sequences from Africans, Europeans, and Asians, and asks students to determine whether people from each continent qualify as distinct "races." Comparison of the DNA sequences shows that people on each continent are not more similar to one another than to people on other continents, and therefore do not qualify as distinct races. Ninety-four percent of our students reported that the laboratory was interesting, and 79% reported that it was a valuable learning experience. We developed and used a survey to measure the extent to which students recognized variation and its significance within populations and showed that the lab increased student awareness of variation. We also showed that the lab improved the ability of students to construct hypothetico-deductive arguments.

  17. 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...

  18. Genome-wide analysis of signatures of selection in populations of African honey bees (Apis mellifera) using new web-based tools.

    Science.gov (United States)

    Fuller, Zachary L; Niño, Elina L; Patch, Harland M; Bedoya-Reina, Oscar C; Baumgarten, Tracey; Muli, Elliud; Mumoki, Fiona; Ratan, Aakrosh; McGraw, John; Frazier, Maryann; Masiga, Daniel; Schuster, Stephen; Grozinger, Christina M; Miller, Webb

    2015-07-10

    With the development of inexpensive, high-throughput sequencing technologies, it has become feasible to examine questions related to population genetics and molecular evolution of non-model species in their ecological contexts on a genome-wide scale. Here, we employed a newly developed suite of integrated, web-based programs to examine population dynamics and signatures of selection across the genome using several well-established tests, including F ST, pN/pS, and McDonald-Kreitman. We applied these techniques to study populations of honey bees (Apis mellifera) in East Africa. In Kenya, there are several described A. mellifera subspecies, which are thought to be localized to distinct ecological regions. We performed whole genome sequencing of 11 worker honey bees from apiaries distributed throughout Kenya and identified 3.6 million putative single-nucleotide polymorphisms. The dense coverage allowed us to apply several computational procedures to study population structure and the evolutionary relationships among the populations, and to detect signs of adaptive evolution across the genome. While there is considerable gene flow among the sampled populations, there are clear distinctions between populations from the northern desert region and those from the temperate, savannah region. We identified several genes showing population genetic patterns consistent with positive selection within African bee populations, and between these populations and European A. mellifera or Asian Apis florea. These results lay the groundwork for future studies of adaptive ecological evolution in honey bees, and demonstrate the use of new, freely available web-based tools and workflows ( http://usegalaxy.org/r/kenyanbee ) that can be applied to any model system with genomic information.

  19. Effects of natural selection and gene conversion on the evolution of human glycophorins coding for MNS blood polymorphisms in malaria-endemic African populations.

    Science.gov (United States)

    Ko, Wen-Ya; Kaercher, Kristin A; Giombini, Emanuela; Marcatili, Paolo; Froment, Alain; Ibrahim, Muntaser; Lema, Godfrey; Nyambo, Thomas B; Omar, Sabah A; Wambebe, Charles; Ranciaro, Alessia; Hirbo, Jibril B; Tishkoff, Sarah A

    2011-06-10

    Malaria has been a very strong selection pressure in recent human evolution, particularly in Africa. Of the one million deaths per year due to malaria, more than 90% are in sub-Saharan Africa, a region with high levels of genetic variation and population substructure. However, there have been few studies of nucleotide variation at genetic loci that are relevant to malaria susceptibility across geographically and genetically diverse ethnic groups in Africa. Invasion of erythrocytes by Plasmodium falciparum parasites is central to the pathology of malaria. Glycophorin A (GYPA) and B (GYPB), which determine MN and Ss blood types, are two major receptors that are expressed on erythrocyte surfaces and interact with parasite ligands. We analyzed nucleotide diversity of the glycophorin gene family in 15 African populations with different levels of malaria exposure. High levels of nucleotide diversity and gene conversion were found at these genes. We observed divergent patterns of genetic variation between these duplicated genes and between different extracellular domains of GYPA. Specifically, we identified fixed adaptive changes at exons 3-4 of GYPA. By contrast, we observed an allele frequency spectrum skewed toward a significant excess of intermediate-frequency alleles at GYPA exon 2 in many populations; the degree of spectrum distortion is correlated with malaria exposure, possibly because of the joint effects of gene conversion and balancing selection. We also identified a haplotype causing three amino acid changes in the extracellular domain of glycophorin B. This haplotype might have evolved adaptively in five populations with high exposure to malaria. Copyright © 2011 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  20. Impact of supplemental site grants to increase African American accrual for the Selenium and Vitamin E Cancer Prevention Trial.

    Science.gov (United States)

    Cook, Elise D; Arnold, Kathryn B; Hermos, John A; McCaskill-Stevens, Worta; Moody-Thomas, Sarah; Probstfield, Jeffrey L; Hamilton, Sandra J; Campbell, Russell D; Anderson, Karen B; Minasian, Lori M

    2010-02-01

    African American accrual to prevention trials at rates representative of the disease burden experienced by this population requires additional resources and focused efforts. To describe the rationale, context, and criteria for selection of sites that received Minority Recruitment Enhancement Grants (MREGs) to increase African American recruitment to the Selenium and Vitamin E Cancer Prevention Trial (SELECT). To determine if African American accrual was higher among the 15 MREG sites when compared with similar nonawarded sites. Changes in African American accrual at sites that received MREGs are compared with changes in a group of 15, frequency-matched, nonawarded sites using a quasi-experimental, post hoc analysis. Successful and unsuccessful recruitment strategies reported by the MREG sites are described. The increased number of African American participants accrued per month at MREG sites post-funding was higher than the change at comparison sites by a factor of 3.38 (p = 0.004, 95% CI: 1.51-7.57). An estimated 602 additional African American participants were recruited at MREG sites due to MREG funding, contributing to the overall 14.9% African American recruitment. Successful recruitment strategies most reported by MREG sites included increasing staff, transportation resources, recruiting through the media, mailings, and prostate cancer screening clinics during off-hours. Comparison sites were chosen retrospectively, not by randomization. Although comparison sites were selected to be similar to MREG sites with regard to potential confounding factors, it is possible that unknown factors could have biased results. Cost-effective analyses were not conducted. MREG sites increased African American accrual in the post-funding period more than comparison sites, indicating MREG funding enhanced the sites' abilities to accrue African American participants. Targeted grants early in the accrual period may be a useful multi-site intervention to increase African American

  1. 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

  2. Surveillance for cancer recurrence in long-term young breast cancer survivors randomly selected from a statewide cancer registry.

    Science.gov (United States)

    Jones, Tarsha; Duquette, Debra; Underhill, Meghan; Ming, Chang; Mendelsohn-Victor, Kari E; Anderson, Beth; Milliron, Kara J; Copeland, Glenn; Janz, Nancy K; Northouse, Laurel L; Duffy, Sonia M; Merajver, Sofia D; Katapodi, Maria C

    2018-01-20

    This study examined clinical breast exam (CBE) and mammography surveillance in long-term young breast cancer survivors (YBCS) and identified barriers and facilitators to cancer surveillance practices. Data collected with a self-administered survey from a statewide, randomly selected sample of YBCS diagnosed with invasive breast cancer or ductal carcinoma in situ younger than 45 years old, stratified by race (Black vs. White/Other). Multivariate logistic regression models identified predictors of annual CBEs and mammograms. Among 859 YBCS (n = 340 Black; n = 519 White/Other; mean age = 51.0 ± 5.9; diagnosed 11.0 ± 4.0 years ago), the majority (> 85%) reported an annual CBE and a mammogram. Black YBCS in the study were more likely to report lower rates of annual mammography and more barriers accessing care compared to White/Other YBCS. Having a routine source of care, confidence to use healthcare services, perceived expectations from family members and healthcare providers to engage in cancer surveillance, and motivation to comply with these expectations were significant predictors of having annual CBEs and annual mammograms. Cost-related lack of access to care was a significant barrier to annual mammograms. Routine source of post-treatment care facilitated breast cancer surveillance above national average rates. Persistent disparities regarding access to mammography surveillance were identified for Black YBCS, primarily due to lack of access to routine source of care and high out-of-pocket costs. Public health action targeting cancer surveillance in YBCS should ensure routine source of post-treatment care and address cost-related barriers. Clinical Trials Registration Number: NCT01612338.

  3. Evaluation of Randomly Selected Completed Medical Records Sheets in Teaching Hospitals of Jahrom University of Medical Sciences, 2009

    Directory of Open Access Journals (Sweden)

    Mohammad Parsa Mahjob

    2011-06-01

    Full Text Available Background and objective: Medical record documentation, often use to protect the patients legal rights, also providing information for medical researchers, general studies, education of health care staff and qualitative surveys is used. There is a need to control the amount of data entered in the medical record sheets of patients, considering the completion of these sheets is often carried out after completion of service delivery to the patients. Therefore, in this study the prevalence of completeness of medical history, operation reports, and physician order sheets by different documentaries in Jahrom teaching hospitals during year 2009 was analyzed. Methods and Materials: In this descriptive / retrospective study, the 400 medical record sheets of the patients from two teaching hospitals affiliated to Jahrom medical university was randomly selected. The tool of data collection was a checklist based on the content of medical history sheet, operation report and physician order sheets. The data were analyzed by SPSS (Version10 software and Microsoft Office Excel 2003. Results: Average of personal (Demography data entered in medical history, physician order and operation report sheets which is done by department's secretaries were 32.9, 35.8 and 40.18 percent. Average of clinical data entered by physician in medical history sheet is 38 percent. Surgical data entered by the surgeon in operation report sheet was 94.77 percent. Average of data entered by operation room's nurse in operation report sheet was 36.78 percent; Average of physician order data in physician order sheet entered by physician was 99.3 percent. Conclusion: According to this study, the rate of completed record papers reviewed by documentary in Jahrom teaching hospitals were not desirable and in some cases were very weak and incomplete. This deficiency was due to different reason such as medical record documentaries negligence, lack of adequate education for documentaries, High work

  4. Sexual selection has minimal impact on effective population sizes in species with high rates of random offspring mortality: An empirical demonstration using fitness distributions.

    Science.gov (United States)

    Pischedda, Alison; Friberg, Urban; Stewart, Andrew D; Miller, Paige M; Rice, William R

    2015-10-01

    The effective population size (N(e)) is a fundamental parameter in population genetics that influences the rate of loss of genetic diversity. Sexual selection has the potential to reduce N(e) by causing the sex-specific distributions of individuals that successfully reproduce to diverge. To empirically estimate the effect of sexual selection on N(e), we obtained fitness distributions for males and females from an outbred, laboratory-adapted population of Drosophila melanogaster. We observed strong sexual selection in this population (the variance in male reproductive success was ∼14 times higher than that for females), but found that sexual selection had only a modest effect on N(e), which was 75% of the census size. This occurs because the substantial random offspring mortality in this population diminishes the effects of sexual selection on N(e), a result that necessarily applies to other high fecundity species. The inclusion of this random offspring mortality creates a scaling effect that reduces the variance/mean ratios for male and female reproductive success and causes them to converge. Our results demonstrate that measuring reproductive success without considering offspring mortality can underestimate Ne and overestimate the genetic consequences of sexual selection. Similarly, comparing genetic diversity among different genomic components may fail to detect strong sexual selection. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  5. The effects of a nurse case manager and a community health worker team on diabetic control, emergency department visits, and hospitalizations among urban African Americans with type 2 diabetes mellitus: a randomized controlled trial.

    Science.gov (United States)

    Gary, Tiffany L; Batts-Turner, Marian; Yeh, Hsin-Chieh; Hill-Briggs, Felicia; Bone, Lee R; Wang, Nae-Yuh; Levine, David M; Powe, Neil R; Saudek, Christopher D; Hill, Martha N; McGuire, Maura; Brancati, Frederick L

    2009-10-26

    Although African American adults bear a disproportionate burden from diabetes mellitus (DM), few randomized controlled trials have tested culturally appropriate interventions to improve DM care. We randomly assigned 542 African Americans with type 2 DM enrolled in an urban managed care organization to either an intensive or minimal intervention group. The intensive intervention group consisted of all components of the minimal intervention plus individualized, culturally tailored care provided by a nurse case manager (NCM) and a community health worker (CHW), using evidence-based clinical algorithms with feedback to primary care providers (eg, physicians, nurse practitioners, or physician assistants). The minimal intervention consisted of mailings and telephone calls every 6 months to remind participants about preventive screenings. Data on diabetic control were collected at baseline and at 24 months by blind observers; data emergency department (ER) visits and hospitalizations were assessed using administrative data. At baseline, participants had a mean age of 58 years, 73% were women, and 50% were living in poverty. At 24 months, compared with the minimal intervention group, those in the intensive intervention group were 23% less likely to have ER visits (rate difference [RD], -14.5; adjusted rate ratio [RR], 0.77; 95% confidence interval [CI], 0.59-1.00). In on-treatment analyses, the rate reduction was strongest for patients who received the most NCM and CHW visits (RD, -31.0; adjusted RR, 0.66; 95% CI, 0.43-1.00; rate reduction downward arrow 34%). These data suggest that a culturally tailored intervention conducted by an NCM/CHW team reduced ER visits in urban African Americans with type 2 DM. clinicaltrials.gov Identifier: NCT00022750.

  6. 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...... on their transnational engagement in development activities in their countries of origin....

  7. Affinity selection of Nipah and Hendra virus-related vaccine candidates from a complex random peptide library displayed on bacteriophage virus-like particles

    Energy Technology Data Exchange (ETDEWEB)

    Peabody, David S.; Chackerian, Bryce; Ashley, Carlee; Carnes, Eric; Negrete, Oscar

    2017-01-24

    The invention relates to virus-like particles of bacteriophage MS2 (MS2 VLPs) displaying peptide epitopes or peptide mimics of epitopes of Nipah Virus envelope glycoprotein that elicit an immune response against Nipah Virus upon vaccination of humans or animals. Affinity selection on Nipah Virus-neutralizing monoclonal antibodies using random sequence peptide libraries on MS2 VLPs selected peptides with sequence similarity to peptide sequences found within the envelope glycoprotein of Nipah itself, thus identifying the epitopes the antibodies recognize. The selected peptide sequences themselves are not necessarily identical in all respects to a sequence within Nipah Virus glycoprotein, and therefore may be referred to as epitope mimics VLPs displaying these epitope mimics can serve as vaccine. On the other hand, display of the corresponding wild-type sequence derived from Nipah Virus and corresponding to the epitope mapped by affinity selection, may also be used as a vaccine.

  8. 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 ...

  9. African Journals Online (AJOL)

    African Journals Online (AJOL)

    Continuing Medical Education; Educational leadership and management: theory, policy and practice. South African Journal of Education; An approach to the neck mass. Continuing Medical Education; The Influence of Motivation on Employees' Performance: A Study of Some Selected Firms in Anambra State AFRREV IJAH: ...

  10. African Journals Online (AJOL)

    African Journals Online (AJOL)

    Ethiopian Journal of Education and Sciences; An approach to the neck mass. Continuing Medical Education; Educational leadership and management: theory, policy and practice. South African Journal of Education; The Influence of Motivation on Employees' Performance: A Study of Some Selected Firms in Anambra State

  11. African Journals Online (AJOL)

    African Journals Online (AJOL)

    ... Employees' Performance: A Study of Some Selected Firms in Anambra State AFRREV IJAH: An International Journal of Arts and Humanities; Production of probiotic mixed pickles (Tursu) and microbiological properties. African Journal of Biotechnology; Educational leadership and management: theory, policy and practice

  12. African Journals Online (AJOL)

    African Journals Online (AJOL)

    Sokoto Journal of Veterinary Sciences; The competitive advantage of nations: is Porter's Diamond Framework a new theory that explains the international competitiveness of countries? Southern African Business Review; The Influence of Motivation on Employees' Performance: A Study of Some Selected Firms in Anambra ...

  13. African Journals Online (AJOL)

    African Journals Online (AJOL)

    Journal of Business and Administrative Studies; An approach to the neck mass. Continuing Medical Education; Educational leadership and management: theory, policy and practice. South African Journal of Education; The Influence of Motivation on Employees' Performance: A Study of Some Selected Firms in Anambra ...

  14. Bias in the prediction of genetic gain due to mass and half-sib selection in random mating populations

    Directory of Open Access Journals (Sweden)

    José Marcelo Soriano Viana

    2009-01-01

    Full Text Available The prediction of gains from selection allows the comparison of breeding methods and selection strategies, although these estimates may be biased. The objective of this study was to investigate the extent of such bias in predicting genetic gain. For this, we simulated 10 cycles of a hypothetical breeding program that involved seven traits, three population classes, three experimental conditions and two breeding methods (mass and half-sib selection. Each combination of trait, population, heritability, method and cycle was repeated 10 times. The predicted gains were biased, even when the genetic parameters were estimated without error. Gain from selection in both genders is twice the gain from selection in a single gender only in the absence of dominance. The use of genotypic variance or broad sense heritability in the predictions represented an additional source of bias. Predictions based on additive variance and narrow sense heritability were equivalent, as were predictions based on genotypic variance and broad sense heritability. The predictions based on mass and family selection were suitable for comparing selection strategies, whereas those based on selection within progenies showed the largest bias and lower association with the realized gain.

  15. Taking ACTION to reduce pain: ACTION study rationale, design and protocol of a randomized trial of a proactive telephone-based coaching intervention for chronic musculoskeletal pain among African Americans.

    Science.gov (United States)

    Bhimani, Rozina H; Cross, Lee J S; Taylor, Brent C; Meis, Laura A; Fu, Steven S; Allen, Kelli D; Krein, Sarah L; Do, Tam; Kerns, Robert D; Burgess, Diana J

    2017-01-13

    Rates of chronic pain are rising sharply in the United States and worldwide. Presently, there is evidence of racial disparities in pain treatment and treatment outcomes in the United States but few interventions designed to address these disparities. There is growing consensus that chronic musculoskeletal pain is best addressed by a biopsychosocial approach that acknowledges the role of psychological and environmental factors, some of which differ by race. The primary aim of this randomized controlled trial is to test the effectiveness of a non-pharmacological, self-regulatory intervention, administered proactively by telephone, at improving pain outcomes and increasing walking among African American patients with hip, back and knee pain. Participants assigned to the intervention will receive a telephone counselor delivered pedometer-mediated walking intervention that incorporates action planning and motivational interviewing. The intervention will consist of 6 telephone counseling sessions over an 8-10 week period. Participants randomly assigned to Usual Care will receive an informational brochure and a pedometer. The primary outcome is chronic pain-related physical functioning, assessed at 6 months, by the revised Roland and Morris Disability Questionnaire, a measure recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT). We will also examine whether the intervention improves other IMMPACT-recommended domains (pain intensity, emotional functioning, and ratings of overall improvement). Secondary objectives include examining whether the intervention reduces health care service utilization and use of opioid analgesics and whether key contributors to racial/ethnic disparities targeted by the intervention mediate improvement in chronic pain outcomes Measures will be assessed by mail and phone surveys at baseline, three months, and six months. Data analysis of primary aims will follow intent-to-treat methodology. We

  16. Expressed sequence tags of randomly selected cDNA clones from Eucalyptus globulus-Pisolithus tinctorius ectomycorrhiza.

    Science.gov (United States)

    Tagu, D; Martin, F

    1995-01-01

    Random sequencing of cDNA clones from Eucalyptus globulus-Pisolithus tinctorius ectomycorrhizal tissues was carried out to generate expressed sequence tags (ESTs). Database comparisons revealed that 42% of the cDNAs corresponded to previously sequenced genes. These ESTs represent efficient molecular markers to analyze changes in gene expression during the formation of the ectomycorrhizal symbiosis.

  17. Impact of Selection Bias on Treatment Effect Size Estimates in Randomized Trials of Oral Health Interventions: A Meta-epidemiological Study.

    Science.gov (United States)

    Saltaji, H; Armijo-Olivo, S; Cummings, G G; Amin, M; da Costa, B R; Flores-Mir, C

    2018-01-01

    Emerging evidence suggests that design flaws of randomized controlled trials can result in over- or underestimation of the treatment effect size (ES). The objective of this study was to examine associations between treatment ES estimates and adequacy of sequence generation, allocation concealment, and baseline comparability among a sample of oral health randomized controlled trials. For our analysis, we selected all meta-analyses that included a minimum of 5 oral health randomized controlled trials and used continuous outcomes. We extracted data, in duplicate, related to items of selection bias (sequence generation, allocation concealment, and baseline comparability) in the Cochrane Risk of Bias tool. Using a 2-level meta-meta-analytic approach with a random effects model to allow for intra- and inter-meta-analysis heterogeneity, we quantified the impact of selection bias on the magnitude of ES estimates. We identified 64 meta-analyses, including 540 randomized controlled trials analyzing 137,957 patients. Sequence generation was judged to be adequate (at low risk of bias) in 32% ( n = 173) of trials, and baseline comparability was judged to be adequate in 77.8% of trials. Allocation concealment was unclear in the majority of trials ( n = 458, 84.8%). We identified significantly larger treatment ES estimates in trials that had inadequate/unknown sequence generation (difference in ES = 0.13; 95% CI: 0.01 to 0.25) and inadequate/unknown allocation concealment (difference in ES = 0.15; 95% CI: 0.02 to 0.27). In contrast, baseline imbalance (difference in ES = 0.01, 95% CI: -0.09 to 0.12) was not associated with inflated or underestimated ES. In conclusion, treatment ES estimates were 0.13 and 0.15 larger in trials with inadequate/unknown sequence generation and inadequate/unknown allocation concealment, respectively. Therefore, authors of systematic reviews using oral health randomized controlled trials should perform sensitivity analyses based on the adequacy of

  18. 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 ...

  19. Aspects of the phytogeography of African Pteridophyta

    Directory of Open Access Journals (Sweden)

    E. A. C. L. E. Schelpe

    1983-12-01

    Full Text Available A diversity of distribution patterns exhibited by African pteridophytes on intercontinental and continental scales are presented. Occasional random dispersal among the Pteridophyta over long distances is accepted. The ecological importance of the gametophyte phase is inferred. Future progress in the elucidation of African fern phytogeography will require a broader alpha-taxonomic pan-African base and the plotting of many more distribution maps.

  20. 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,

  1. Selecting students for a South African mathematics and science foundation programme: effectiveness and fairness of school-leaving examinations and aptitude tests.

    NARCIS (Netherlands)

    van der Flier, H.; Thijs, G.D.; Zaaiman, H.

    2003-01-01

    The identification of students with the potential to succeed in mathematics- and science-based study despite previous educational disadvantage is a critical issue currently facing many South African higher education institutions. The possible use of school-leaving examination (Matric) results and/or

  2. Selecting Communication Channels for Substance Misuse Prevention with At-Risk African-American Emerging Adults Living in the Southern United States

    Science.gov (United States)

    Tucker, Jalie A.; Cheong, JeeWon; Chandler, Susan D.

    2016-01-01

    Natural health information sources used by African-American emerging adults were investigated to identify sources associated with high and low substance-related risk. Participants (110 males, 234 females; M age = 18.9 years) were recruited using respondent-driven sampling, and structured interviews assessed substance use, sources of health…

  3. A Brief, Web-based Personalized Feedback Selective Intervention for College Student Marijuana Use: A Randomized Clinical Trial

    OpenAIRE

    Lee, Christine M.; Neighbors, Clayton; Kilmer, Jason R; Larimer, Mary E.

    2010-01-01

    Despite clear need, brief web-based interventions for marijuana using college students have not been evaluated in the literature. The current study was designed to evaluate a brief, web-based personalized feedback intervention for at-risk marijuana users transitioning to college. All entering first-year students were invited to complete a brief questionnaire. Participants meeting criteria completed a baseline assessment (N = 341) and were randomly assigned to web-based personalized feedback o...

  4. A Randomized Comparative Study of Pulsed Radiofrequency Treatment With or Without Selective Nerve Root Block for Chronic Cervical Radicular Pain.

    Science.gov (United States)

    Wang, Fei; Zhou, Qian; Xiao, Lizu; Yang, Juan; Xong, Donglin; Li, Disen; Liu, LiPing; Ancha, Sigdha; Cheng, Jianguo

    2017-06-01

    We demonstrated a combination of pulsed radiofrequency (PRF) and cervical nerve root block (CNRB) via a posterior approach was superior to a transforaminal epidural steroid injection through the anterolateral approach for cervical radicular pain in a previous study. This randomized trial was conducted to determine the comparative efficacy between CNRB, PRF, and CNRB + PRF for cervical radicular pain. A prospective and randomized design was used in this study. Sixty-two patients were randomized into three parallel groups: CNRB, PRF, or CNRB + PRF. Numeric Rating Scale (NRS) was used to measure pain intensity, and global perceived effect (GPE) was scored by the patient on a 7-point scale, ranging from much worse (-3), no change (0), to total improvement (+3). The outcomes were evaluated at 1 week, 1 month, 3 months, and 6 months. Side effects and complications were noted. The NRS was significantly reduced in all three groups 1 week after the treatments (P 0.05). No serious complications were observed in any of the patients. Combining CNRB and PRF appeared to be a safe and efficacious technique for cervical radicular pain. The combination therapy yielded better outcomes than either CNRB or PRF alone. © 2016 World Institute of Pain.

  5. Use of hyaluronan in the selection of sperm for intracytoplasmic sperm injection (ICSI): significant improvement in clinical outcomes--multicenter, double-blinded and randomized controlled trial.

    Science.gov (United States)

    Worrilow, K C; Eid, S; Woodhouse, D; Perloe, M; Smith, S; Witmyer, J; Ivani, K; Khoury, C; Ball, G D; Elliot, T; Lieberman, J

    2013-02-01

    Does the selection of sperm for ICSI based on their ability to bind to hyaluronan improve the clinical pregnancy rates (CPR) (primary end-point), implantation (IR) and pregnancy loss rates (PLR)? In couples where ≤ 65% of sperm bound hyaluronan, the selection of hyaluronan-bound (HB) sperm for ICSI led to a statistically significant reduction in PLR. HB sperm demonstrate enhanced developmental parameters which have been associated with successful fertilization and embryogenesis. Sperm selected for ICSI using a liquid source of hyaluronan achieved an improvement in IR. A pilot study by the primary author demonstrated that the use of HB sperm in ICSI was associated with improved CPR. The current study represents the single largest prospective, multicenter, double-blinded and randomized controlled trial to evaluate the use of hyaluronan in the selection of sperm for ICSI. Using the hyaluronan binding assay, an HB score was determined for the fresh or initial (I-HB) and processed or final semen specimen (F-HB). Patients were classified as >65% or ≤ 65% I-HB and stratified accordingly. Patients with I-HB scores ≤ 65% were randomized into control and HB selection (HYAL) groups whereas patients with I-HB >65% were randomized to non-participatory (NP), control or HYAL groups, in a ratio of 2:1:1. The NP group was included in the >65% study arm to balance the higher prevalence of patients with I-HB scores >65%. In the control group, oocytes received sperm selected via the conventional assessment of motility and morphology. In the HYAL group, HB sperm meeting the same visual criteria were selected for injection. Patient participants and clinical care providers were blinded to group assignment. Eight hundred two couples treated with ICSI in 10 private and hospital-based IVF programs were enrolled in this study. Of the 484 patients stratified to the I-HB > 65% arm, 115 participants were randomized to the control group, 122 participants were randomized to the HYAL group

  6. The prevalence and classification of chronic kidney disease in cats randomly selected within four age groups and in cats recruited for degenerative joint disease studies

    Science.gov (United States)

    Marino, Christina L; Lascelles, B Duncan X; Vaden, Shelly L; Gruen, Margaret E; Marks, Steven L

    2015-01-01

    Chronic kidney disease (CKD) and degenerative joint disease are both considered common in older cats. Information on the co-prevalence of these two diseases is lacking. This retrospective study was designed to determine the prevalence of CKD in two cohorts of cats: cats randomly selected from four evenly distributed age groups (RS group) and cats recruited for degenerative joint disease studies (DJD group), and to evaluate the concurrence of CKD and DJD in these cohorts. The RS group was randomly selected from four age groups from 6 months to 20 years, and the DJD group comprised cats recruited to four previous DJD studies, with the DJD group excluding cats with a blood urea nitrogen and/or serum creatinine concentration >20% (the upper end of normal) for two studies and cats with CKD stages 3 and 4 for the other two studies. The prevalence of CKD in the RS and DJD groups was higher than expected at 50% and 68.8%, respectively. CKD was common in cats between 1 and 15 years of age, with a similar prevalence of CKD stages 1 and 2 across age groups in both the RS and DJD cats, respectively. We found significant concurrence between CKD and DJD in cats of all ages, indicating the need for increased screening for CKD when selecting DJD treatments. Additionally, this study offers the idea of a relationship and causal commonality between CKD and DJD owing to the striking concurrence across age groups and life stages. PMID:24217707

  7. Blood Selenium Concentration and Blood Cystatin C Concentration in a Randomly Selected Population of Healthy Children Environmentally Exposed to Lead and Cadmium.

    Science.gov (United States)

    Gać, Paweł; Pawlas, Natalia; Wylężek, Paweł; Poręba, Rafał; Poręba, Małgorzata; Pawlas, Krystyna

    2017-01-01

    This study aimed at evaluation of a relationship between blood selenium concentration (Se-B) and blood cystatin C concentration (CST) in a randomly selected population of healthy children, environmentally exposed to lead and cadmium. The studies were conducted on 172 randomly selected children (7.98 ± 0.97 years). Among participants, the subgroups were distinguished, manifesting marginally low blood selenium concentration (Se-B 40-59 μg/l), suboptimal blood selenium concentration (Se-B: 60-79 μg/l) or optimal blood selenium concentration (Se-B ≥ 80 μg/l). At the subsequent stage, analogous subgroups of participants were selected separately in groups of children with BMI below median value (BMI selenium concentration and blood cystatin C concentration. On the other hand, in children with low body mass index, a negative non-linear relationship was present between blood selenium concentration and blood cystatin C concentration.

  8. Prevalence and classification of chronic kidney disease in cats randomly selected from four age groups and in cats recruited for degenerative joint disease studies.

    Science.gov (United States)

    Marino, Christina L; Lascelles, B Duncan X; Vaden, Shelly L; Gruen, Margaret E; Marks, Steven L

    2014-06-01

    Chronic kidney disease (CKD) and degenerative joint disease are both considered common in older cats. Information on the co-prevalence of these two diseases is lacking. This retrospective study was designed to determine the prevalence of CKD in two cohorts of cats: cats randomly selected from four evenly distributed age groups (RS group) and cats recruited for degenerative joint disease studies (DJD group), and to evaluate the concurrence of CKD and DJD in these cohorts. The RS group was randomly selected from four age groups from 6 months to 20 years, and the DJD group comprised cats recruited to four previous DJD studies, with the DJD group excluding cats with a blood urea nitrogen and/or serum creatinine concentration >20% (the upper end of normal) for two studies and cats with CKD stages 3 and 4 for the other two studies. The prevalence of CKD in the RS and DJD groups was higher than expected at 50% and 68.8%, respectively. CKD was common in cats between 1 and 15 years of age, with a similar prevalence of CKD stages 1 and 2 across age groups in both the RS and DJD cats, respectively. We found significant concurrence between CKD and DJD in cats of all ages, indicating the need for increased screening for CKD when selecting DJD treatments. Additionally, this study offers the idea of a relationship and causal commonality between CKD and DJD owing to the striking concurrence across age groups and life stages. © ISFM and AAFP 2013.

  9. SNPs selected by information content outperform randomly selected microsatellite loci for delineating genetic identification and introgression in the endangered dark European honeybee (Apis mellifera mellifera).

    Science.gov (United States)

    Muñoz, Irene; Henriques, Dora; Jara, Laura; Johnston, J Spencer; Chávez-Galarza, Julio; De La Rúa, Pilar; Pinto, M Alice

    2017-07-01

    The honeybee (Apis mellifera) has been threatened by multiple factors including pests and pathogens, pesticides and loss of locally adapted gene complexes due to replacement and introgression. In western Europe, the genetic integrity of the native A. m. mellifera (M-lineage) is endangered due to trading and intensive queen breeding with commercial subspecies of eastern European ancestry (C-lineage). Effective conservation actions require reliable molecular tools to identify pure-bred A. m. mellifera colonies. Microsatellites have been preferred for identification of A. m. mellifera stocks across conservation centres. However, owing to high throughput, easy transferability between laboratories and low genotyping error, SNPs promise to become popular. Here, we compared the resolving power of a widely utilized microsatellite set to detect structure and introgression with that of different sets that combine a variable number of SNPs selected for their information content and genomic proximity to the microsatellite loci. Contrary to every SNP data set, microsatellites did not discriminate between the two lineages in the PCA space. Mean introgression proportions were identical across the two marker types, although at the individual level, microsatellites' performance was relatively poor at the upper range of Q-values, a result reflected by their lower precision. Our results suggest that SNPs are more accurate and powerful than microsatellites for identification of A. m. mellifera colonies, especially when they are selected by information content. © 2016 John Wiley & Sons Ltd.

  10. African Journals Online: African Studies

    African Journals Online (AJOL)

    Items 1 - 50 of 56 ... The African Journal of Cross-Cultural Psychology and Sport Facilitation will take and publish empirical studies and theoretical propositions as well as ..... The Journal of the Musical Arts in Africa, produced in collaboration with the South African College of Music at University of Cape Town, will henceforth ...

  11. 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.

  12. 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...

  13. 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...

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

    OpenAIRE

    Badham, Jane Melissa; Bosman, Magdalena Johanna Catharina; Ellis, Susanna Maria; Jerling, Johann Carl; Van der Merwe, Magdalena

    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 metropolitan and rural...

  15. Acute changes of hip joint range of motion using selected clinical stretching procedures: A randomized crossover study.

    Science.gov (United States)

    Hammer, Adam M; Hammer, Roger L; Lomond, Karen V; O'Connor, Paul

    2017-09-01

    Hip adductor flexibility and strength is an important component of athletic performance and many activities of daily living. Little research has been done on the acute effects of a single session of stretching on hip abduction range of motion (ROM). The aim of this study was to compare 3 clinical stretching procedures against passive static stretching and control on ROM and peak isometric maximal voluntary contraction (MVC). Using a randomized crossover study design, a total of 40 participants (20 male and 20 female) who had reduced hip adductor muscle length attended a familiarization session and 5 testing sessions on non-consecutive days. Following the warm-up and pre-intervention measures of ROM and MVC, participants were randomly assigned 1 of 3 clinical stretching procedures (modified lunge, multidirectional, and joint mobilization) or a static stretch or control condition. Post-intervention measures of ROM and MVC were taken immediately following completion of the assigned condition. An ANOVA using a repeated measure design with the change score was conducted. All interventions resulted in small but statistically significant (p stretching was greater than control (p = 0.031). These data suggest that a single session of stretching has only a minimal effect on acute changes of hip abduction ROM. Although hip abduction is a frontal plane motion, to effectively increase the extensibility of the structures that limit abduction, integrating multi-planar stretches may be indicated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Selepressin, a novel selective vasopressin V1A agonist, is an effective substitute for norepinephrine in a phase IIa randomized, placebo-controlled trial in septic shock patients

    DEFF Research Database (Denmark)

    Russell, James A; Vincent, Jean-Louis; Kjølbye, Anne Louise

    2017-01-01

    BACKGROUND: Vasopressin is widely used for vasopressor support in septic shock patients, but experimental evidence suggests that selective V1A agonists are superior. The initial pharmacodynamic effects, pharmacokinetics, and safety of selepressin, a novel V1A-selective vasopressin analogue......, was examined in a phase IIa trial in septic shock patients. METHODS: This was a randomized, double-blind, placebo-controlled multicenter trial in 53 patients in early septic shock (aged ≥18 years, fluid resuscitation, requiring vasopressor support) who received selepressin 1.25 ng/kg/minute (n = 10), 2.5 ng...... for selepressin 2.5 ng/kg/minute and placebo. Two patients were infused at 3.75 ng/kg/minute, one of whom had the study drug infusion discontinued for possible safety reasons, with subsequent discontinuation of this dose group. CONCLUSIONS: In septic shock patients, selepressin 2.5 ng/kg/minute was able...

  17. Frequency of glucose-6-phosphate dehydrogenase deficiency in malaria patients from six African countries enrolled in two randomized anti-malarial clinical trials

    Directory of Open Access Journals (Sweden)

    Duparc Stephan

    2011-08-01

    Full Text Available Abstract Background Glucose-6-phosphate dehydrogenase (G6PD deficiency is common in populations living in malaria endemic areas. G6PD genotype and phenotype were determined for malaria patients enrolled in the chlorproguanil-dapsone-artesunate (CDA phase III clinical trial programme. Methods Study participants, aged > 1 year, with microscopically confirmed uncomplicated Plasmodium falciparum malaria, and haemoglobin ≥ 70 g/L or haematocrit ≥ 25%, were recruited into two clinical trials conducted in six African countries (Burkina Faso, Ghana, Kenya, Nigeria, Tanzania, Mali. G6PD genotype of the three most common African forms, G6PD*B, G6PD*A (A376G, and G6PD*A- (G202A, A542T, G680T and T968C, were determined and used for frequency estimation. G6PD phenotype was assessed qualitatively using the NADPH fluorescence test. Exploratory analyses investigated the effect of G6PD status on baseline haemoglobin concentration, temperature, asexual parasitaemia and anti-malarial efficacy after treatment with CDA 2/2.5/4 mg/kg or chlorproguanil-dapsone 2/2.5 mg/kg (both given once daily for three days or six-dose artemether-lumefantrine. Results Of 2264 malaria patients enrolled, 2045 had G6PD genotype available and comprised the primary analysis population (1018 males, 1027 females. G6PD deficiency prevalence was 9.0% (184/2045; 7.2% [N = 147] male hemizygous plus 1.8% [N = 37] female homozygous, 13.3% (273/2045 of patients were heterozygous females, 77.7% (1588/2045 were G6PD normal. All deficient G6PD*A- genotypes were A376G/G202A. G6PD phenotype was available for 64.5% (1319/2045 of patients: 10.2% (134/1319 were G6PD deficient, 9.6% (127/1319 intermediate, and 80.2% (1058/1319 normal. Phenotype test specificity in detecting hemizygous males was 70.7% (70/99 and 48.0% (12/25 for homozygous females. Logistic regression found no significant effect of G6PD genotype on adjusted mean baseline haemoglobin (p = 0.154, adjusted mean baseline temperature (p = 0

  18. Frequency of glucose-6-phosphate dehydrogenase deficiency in malaria patients from six African countries enrolled in two randomized anti-malarial clinical trials

    Science.gov (United States)

    2011-01-01

    Background Glucose-6-phosphate dehydrogenase (G6PD) deficiency is common in populations living in malaria endemic areas. G6PD genotype and phenotype were determined for malaria patients enrolled in the chlorproguanil-dapsone-artesunate (CDA) phase III clinical trial programme. Methods Study participants, aged > 1 year, with microscopically confirmed uncomplicated Plasmodium falciparum malaria, and haemoglobin ≥ 70 g/L or haematocrit ≥ 25%, were recruited into two clinical trials conducted in six African countries (Burkina Faso, Ghana, Kenya, Nigeria, Tanzania, Mali). G6PD genotype of the three most common African forms, G6PD*B, G6PD*A (A376G), and G6PD*A- (G202A, A542T, G680T and T968C), were determined and used for frequency estimation. G6PD phenotype was assessed qualitatively using the NADPH fluorescence test. Exploratory analyses investigated the effect of G6PD status on baseline haemoglobin concentration, temperature, asexual parasitaemia and anti-malarial efficacy after treatment with CDA 2/2.5/4 mg/kg or chlorproguanil-dapsone 2/2.5 mg/kg (both given once daily for three days) or six-dose artemether-lumefantrine. Results Of 2264 malaria patients enrolled, 2045 had G6PD genotype available and comprised the primary analysis population (1018 males, 1027 females). G6PD deficiency prevalence was 9.0% (184/2045; 7.2% [N = 147] male hemizygous plus 1.8% [N = 37] female homozygous), 13.3% (273/2045) of patients were heterozygous females, 77.7% (1588/2045) were G6PD normal. All deficient G6PD*A- genotypes were A376G/G202A. G6PD phenotype was available for 64.5% (1319/2045) of patients: 10.2% (134/1319) were G6PD deficient, 9.6% (127/1319) intermediate, and 80.2% (1058/1319) normal. Phenotype test specificity in detecting hemizygous males was 70.7% (70/99) and 48.0% (12/25) for homozygous females. Logistic regression found no significant effect of G6PD genotype on adjusted mean baseline haemoglobin (p = 0.154), adjusted mean baseline temperature (p = 0.9617), or

  19. Lexical borrowings and calques from African American slang in Polish youth slang – A study based on a selected internet forum

    OpenAIRE

    Dylewski, Radosław; Jagodziński, Piotr

    2012-01-01

    The aim of the article is to present a very preliminary chunk of a wider study of Polish slang, whose aim is to pinpoint lexical influence of American English in broad terms and the usage and understanding among Polish youngsters of various types of borrowings. More specifically, the authors have concentrated on the borrowings of words, phrases and meanings from a sociolect known as African American English to the language of Polish youngsters. To this end, the largest Polish hard...

  20. Early routine versus late selective surfactant in preterm neonates with respiratory distress syndrome on nasal continuous positive airway pressure: a randomized controlled trial.

    Science.gov (United States)

    Kandraju, Hemasree; Murki, Srinivas; Subramanian, Sreeram; Gaddam, Pramod; Deorari, Ashok; Kumar, Praveen

    2013-01-01

    Preterm neonates with respiratory distress syndrome (RDS) benefit from early application of nasal continuous positive airway pressure (nCPAP). However, it is not clear whether surfactant should be administered early as a routine to all such infants or later in a selective manner. It was the aim of this study to compare the efficacy of early routine versus late selective surfactant treatment in reducing the need for mechanical ventilation (MV) during the first week of life among moderate-sized preterm infants with RDS being supported by nCPAP. Infants born at 28(0/7) to 33(6/7) weeks of gestation with RDS and on nCPAP were randomly assigned within the first 2 h of life to early routine surfactant administration by the InSurE technique (early surfactant group) or to late selective administration of surfactant (late surfactant group). The primary outcome was need for MV in the first 7 days of life. Among 153 infants randomized to early (n = 74) or late surfactant (n = 79) groups, the need for MV was significantly lower in the early surfactant group (16.2 vs. 31.6%; relative risk 0.41, 95% confidence interval 0.19-0.91). The incidence of pneumothorax (1.9 vs. 2.3%) and the need for supplemental O2 at 28 days (2.7 vs. 8.9%) were similar in the two groups. Early routine surfactant administration within 2 h of life as compared to late selective administration significantly reduced the need for MV in the first week of life among preterm infants with RDS on nCPAP. Copyright © 2012 S. Karger AG, Basel.

  1. Does Multimodal Analgesia with Acetaminophen, Nonsteroidal Antiinflammatory Drugs, or Selective Cyclooxygenase-2 Inhibitors and Patient-controlled Analgesia Morphine Offer Advantages over Morphine Alone?: Meta-analyses of Randomized Trials

    National Research Council Canada - National Science Library

    Elia, Nadia; Lysakowski, Christopher; Tramèr, Martin R

    2005-01-01

    The authors analyzed data from 52 randomized placebo-controlled trials (4,893 adults) testing acetaminophen, nonsteroidal antiinflammatory drugs, or selective cyclooxygenase-2 inhibitors given in conjunction with morphine after surgery...

  2. "Open mesh" or "strictly selected population" recruitment? The experience of the randomized controlled MeMeMe trial

    Directory of Open Access Journals (Sweden)

    Cortellini M

    2017-07-01

    Full Text Available Mauro Cortellini, Franco Berrino, Patrizia Pasanisi Department of Preventive & Predictive Medicine, Foundation IRCCS National Cancer Institute of Milan, Milan, Italy Abstract: Among randomized controlled trials (RCTs, trials for primary prevention require large samples and long follow-up to obtain a high-quality outcome; therefore the recruitment process and the drop-out rates largely dictate the adequacy of the results. We are conducting a Phase III trial on persons with metabolic syndrome to test the hypothesis that comprehensive lifestyle changes and/or metformin treatment prevents age-related chronic diseases (the MeMeMe trial, EudraCT number: 2012-005427-32, also registered on ClinicalTrials.gov [NCT02960711]. Here, we briefly analyze and discuss the reasons which may lead to participants dropping out from trials. In our experience, participants may back out of a trial for different reasons. Drug-induced side effects are certainly the most compelling reason. But what are the other reasons, relating to the participants’ perception of the progress of the trial which led them to withdraw after randomization? What about the time-dependent drop-out rate in primary prevention trials? The primary outcome of this analysis is the point of drop-out from trial, defined as the time from the randomization date to the withdrawal date. Survival functions were non-parametrically estimated using the product-limit estimator. The curves were statistically compared using the log-rank test (P=0.64, not significant. Researchers involved in primary prevention RCTs seem to have to deal with the paradox of the proverbial “short blanket syndrome”. Recruiting only highly motivated candidates might be useful for the smooth progress of the trial but it may lead to a very low enrollment rate. On the other hand, what about enrolling all the eligible subjects without considering their motivation? This might boost the enrollment rate, but it can lead to biased

  3. H-DROP: an SVM based helical domain linker predictor trained with features optimized by combining random forest and stepwise selection.

    Science.gov (United States)

    Ebina, Teppei; Suzuki, Ryosuke; Tsuji, Ryotaro; Kuroda, Yutaka

    2014-08-01

    Domain linker prediction is attracting much interest as it can help identifying novel domains suitable for high throughput proteomics analysis. Here, we report H-DROP, an SVM-based Helical Domain linker pRediction using OPtimal features. H-DROP is, to the best of our knowledge, the first predictor for specifically and effectively identifying helical linkers. This was made possible first because a large training dataset became available from IS-Dom, and second because we selected a small number of optimal features from a huge number of potential ones. The training helical linker dataset, which included 261 helical linkers, was constructed by detecting helical residues at the boundary regions of two independent structural domains listed in our previously reported IS-Dom dataset. 45 optimal feature candidates were selected from 3,000 features by random forest, which were further reduced to 26 optimal features by stepwise selection. The prediction sensitivity and precision of H-DROP were 35.2 and 38.8%, respectively. These values were over 10.7% higher than those of control methods including our previously developed DROP, which is a coil linker predictor, and PPRODO, which is trained with un-differentiated domain boundary sequences. Overall, these results indicated that helical linkers can be predicted from sequence information alone by using a strictly curated training data set for helical linkers and carefully selected set of optimal features. H-DROP is available at http://domserv.lab.tuat.ac.jp.

  4. 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 ...

  5. A selective neurokinin-1 receptor antagonist in chronic PTSD: a randomized, double-blind, placebo-controlled, proof-of-concept trial.

    Science.gov (United States)

    Mathew, Sanjay J; Vythilingam, Meena; Murrough, James W; Zarate, Carlos A; Feder, Adriana; Luckenbaugh, David A; Kinkead, Becky; Parides, Michael K; Trist, David G; Bani, Massimo S; Bettica, Paolo U; Ratti, Emiliangelo M; Charney, Dennis S

    2011-03-01

    The substance P-neurokinin-1 receptor (SP-NK(1)R) system has been extensively studied in experimental models of stress, fear, and reward. Elevated cerebrospinal fluid (CSF) SP levels were reported previously in combat-related PTSD. No medication specifically targeting this system has been tested in PTSD. This proof-of-concept randomized, double-blind, placebo-controlled trial evaluated the selective NK(1)R antagonist GR205171 in predominately civilian PTSD. Following a 2-week placebo lead-in, 39 outpatients with chronic PTSD and a Clinician-Administered PTSD Scale (CAPS) score ≥50 were randomized to a fixed dose of GR205171 (N=20) or placebo (N=19) for 8weeks. The primary endpoint was mean change from baseline to endpoint in the total CAPS score. Response rate (≥50% reduction in baseline CAPS) and safety/tolerability were secondary endpoints. CSF SP concentrations were measured in a subgroup of patients prior to randomization. There was significant improvement in the mean CAPS total score across all patients over time, but no significant difference was found between GR205171 and placebo. Likewise, there was no significant effect of drug on the proportion of responders [40% GR205171 versus 21% placebo (p=0.30)]. An exploratory analysis showed that GR205171 treatment was associated with significant improvement compared to placebo on the CAPS hyperarousal symptom cluster. GR205171 was well-tolerated, with no discontinuations due to adverse events. CSF SP concentrations were positively correlated with baseline CAPS severity. The selective NK(1)R antagonist GR205171 had fewer adverse effects but was not significantly superior to placebo in the short-term treatment of chronic PTSD. (ClinicalTrials.gov Identifier: NCT 00211861, NCT 00383786). Published by Elsevier B.V.

  6. 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 ...

  7. A cluster randomized controlled trial evaluating the efficacy of peer mentors to support South African women living with HIV and their infants.

    Directory of Open Access Journals (Sweden)

    Mary Jane Rotheram-Borus

    Full Text Available We evaluate the effect of clinic-based support by HIV-positive Peer Mentors, in addition to standard clinic care, on maternal and infant well-being among Women Living with HIV (WLH from pregnancy through the infant's first year of life.In a cluster randomized controlled trial in KwaZulu-Natal, South Africa, eight clinics were randomized for pregnant WLH to receive either: a Standard Care condition (SC; 4 clinics; n = 656 WLH; or an Enhanced Intervention (EI; 4 clinics; n = 544 WLH. WLH in the EI were invited to attend four antenatal and four postnatal meetings led by HIV-positive Peer Mentors, in addition to SC. WLH were recruited during pregnancy, and at least two post-birth assessment interviews were completed by 57% of WLH at 1.5, 6 or 12 months. EI's effect was ascertained on 19 measures of maternal and infant well-being using random effects regressions to control for clinic clustering. A binomial test for correlated outcomes evaluated EI's overall efficacy.WLH attended an average of 4.1 sessions (SD = 2.0; 13% did not attend any sessions. Significant overall benefits were found in EI compared to SC using the binomial test. Secondarily, over time, WLH in the EI reported significantly fewer depressive symptoms and fewer underweight infants than WLH in the SC condition. EI WLH were significantly more likely to use one feeding method for six months and exclusively breastfeed their infants for at least 6 months.WLH benefit by support from HIV-positive Peer Mentors, even though EI participation was partial, with incomplete follow-up rates from 6-12 months.ClinicalTrials.gov NCT00972699.

  8. Food pantry selection solutions: a randomized controlled trial in client-choice food pantries to nudge clients to targeted foods.

    Science.gov (United States)

    Wilson, Norbert L W; Just, David R; Swigert, Jeffery; Wansink, Brian

    2017-06-01

    Food pantries and food banks are interested in cost-effective methods to encourage the selection of targeted foods without restricting choices. Thus, this study evaluates the effectiveness of nudges toward targeted foods. In October/November 2014, we manipulated the display of a targeted product in a New York State food pantry. We evaluated the binary choice of the targeted good when we placed it in the front or the back of the category line (placement order) and when we presented the product in its original box or unboxed (packaging). The average uptake proportion for the back treatment was 0.231, 95% CI = 0.179, 0.29, n = 205, and for the front treatment, the proportion was 0.337, 95% CI = 0.272, 0.406, n = 238 with an odds ratio of 1.688, 95% CI = 1.088, 2.523. The average uptake for the unboxed treatment was 0.224, 95% CI = 0.174, 0.280, n = 255, and for the boxed intervention, the proportion was 0.356, 95% CI = 0.288, 0.429, n = 188 with an odds ratio of 1.923, 95% CI = 1.237, 2.991. Nudges increased uptake of the targeted food. The findings also hold when we control for a potential confounder. Low cost and unobtrusive nudges can be effective tools for food pantry organizers to encourage the selection of targeted foods. NCT02403882.

  9. EcmPred: Prediction of extracellular matrix proteins based on random forest with maximum relevance minimum redundancy feature selection

    KAUST Repository

    Kandaswamy, Krishna Kumar Umar

    2013-01-01

    The extracellular matrix (ECM) is a major component of tissues of multicellular organisms. It consists of secreted macromolecules, mainly polysaccharides and glycoproteins. Malfunctions of ECM proteins lead to severe disorders such as marfan syndrome, osteogenesis imperfecta, numerous chondrodysplasias, and skin diseases. In this work, we report a random forest approach, EcmPred, for the prediction of ECM proteins from protein sequences. EcmPred was trained on a dataset containing 300 ECM and 300 non-ECM and tested on a dataset containing 145 ECM and 4187 non-ECM proteins. EcmPred achieved 83% accuracy on the training and 77% on the test dataset. EcmPred predicted 15 out of 20 experimentally verified ECM proteins. By scanning the entire human proteome, we predicted novel ECM proteins validated with gene ontology and InterPro. The dataset and standalone version of the EcmPred software is available at http://www.inb.uni-luebeck.de/tools-demos/Extracellular_matrix_proteins/EcmPred. © 2012 Elsevier Ltd.

  10. Randomized Controlled Trial of Acupuncture for Women with Fibromyalgia: Group Acupuncture with Traditional Chinese Medicine Diagnosis-Based Point Selection.

    Science.gov (United States)

    Mist, Scott D; Jones, Kim Dupree

    2018-02-13

    Group acupuncture is a growing and cost-effective method for delivering acupuncture in the United States and is the practice model in China. However, group acupuncture has not been tested in a research setting. To test the treatment effect of group acupuncture vs group education in persons with fibromyalgia. Random allocation two-group study with repeated measures. Group clinic in an academic health center in Portland, Oregon. Women with confirmed diagnosis of fibromyalgia (American College of Radiology 1990 criteria) and moderate to severe pain levels. Twenty treatments of a manualized acupuncture treatment based on Traditional Chinese Medicine diagnosis or group education over 10 weeks (both 900 minutes total). Weekly Revised Fibromyalgia Impact Questionnaire (FIQR) and Global Fatigue Index at baseline, five weeks, and 10 weeks and a four-week follow-up were assessed. Thirty women were recruited, with 78% reporting symptoms for longer than 10 years. The mean attendance was 810 minutes for acupuncture and 861 minutes for education. FIQR total, FIQR pain, and Global Fatigue Index all had clinically and statistically significant improvement in the group receiving acupuncture at end of treatment and four weeks post-treatment but not in participants receiving group education between groups. Compared with education, group acupuncture improved global symptom impact, pain, and fatigue. Furthermore, it was a safe and well-tolerated treatment option, improving a broader proportion of patients than current pharmaceutical options.

  11. Randomized trial of switching from prescribed non-selective non-steroidal anti-inflammatory drugs to prescribed celecoxib

    DEFF Research Database (Denmark)

    Macdonald, Thomas M; Hawkey, Chris J; Ford, Ian

    2017-01-01

    infarction or other biomarker positive acute coronary syndrome, non-fatal stroke or CV death analysed using a Cox model with a pre-specified non-inferiority limit of 1.4 for the hazard ratio (HR). RESULTS: In total, 7297 participants were randomized. During a median 3-year follow-up, fewer subjects than......-years with celecoxib and 1.10 per 100 patient-years with nsNSAIDs (HR = 1.04; 95% confidence interval, 0.81-1.33; P = 0.75). Pre-specified non-inferiority was achieved in the ITT analysis. The upper bound of the 95% confidence limit for the absolute increase in OT risk associated with celecoxib treatment was two......NSAIDs. There was no advantage of a strategy of switching prescribed nsNSAIDs to prescribed celecoxib. This study excluded an increased risk of the primary endpoint of more than two events per 1000 patient-years associated with switching to prescribed celecoxib....

  12. The effects of iron fortification on the gut microbiota in African children: a randomized controlled trial in Côte d'Ivoire

    NARCIS (Netherlands)

    Zimmermann, M.B.; Chassard, C.; Rohner, F.; N'goran, E.K.; Nindjin, C.; Dostal, A.; Utzinger, J.; Ghattas, H.; Lacroix, C.; Hurrell, R.F.

    2010-01-01

    Background: Iron is essential for the growth and virulence of many pathogenic enterobacteria, whereas beneficial barrier bacteria, such as lactobacilli, do not require iron. Thus, increasing colonic iron could select gut microbiota for humans that are unfavorable to the host. Objective: The

  13. Bulk feeder or selective grazer: African buffalo space use patterns based on fine-scale remotely sensed data on forage quality and quantity

    CSIR Research Space (South Africa)

    Kaszta, Z

    2016-03-01

    Full Text Available Bruxelles, The Institute for Environmental Management and Land-use Planning (Institut de Gestion de l’Environnement et d’Aménagement du Territoire – IGEAT), Avenue F.D. Roosevelt 50, CP130/03, B-1050 Brussels, Belgium b Wildlife Conservation Research... for Environmental Management and Land-use Planning (Institut de Gestion de l’Environnement et d’Aménagement du Territoire – IGEAT), Belgium Abstract The distribution and behaviour of African large grazers are regulated primarily from the bottom up, with some...

  14. Suicide in Nepal: a modified psychological autopsy investigation from randomly selected police cases between 2013 and 2015.

    Science.gov (United States)

    Hagaman, Ashley K; Khadka, S; Lohani, S; Kohrt, B

    2017-12-01

    Yearly, 600,000 people complete suicide in low- and middle-income countries, accounting for 75% of the world's burden of suicide mortality. The highest regional rates are in South and East Asia. Nepal has one of the highest suicide rates in the world; however, few investigations exploring patterns surrounding both male and female suicides exist. This study used psychological autopsies to identify common factors, precipitating events, and warning signs in a diverse sample. Randomly sampled from 302 police case reports over 24 months, psychological autopsies were conducted for 39 completed suicide cases in one urban and one rural region of Nepal. In the total police sample (n = 302), 57.0% of deaths were male. Over 40% of deaths were 25 years or younger, including 65% of rural and 50.8% of female suicide deaths. We estimate the crude urban and rural suicide rates to be 16.1 and 22.8 per 100,000, respectively. Within our psychological autopsy sample, 38.5% met criteria for depression and only 23.1% informants believed that the deceased had thoughts of self-harm or suicide before death. Important warning signs include recent geographic migration, alcohol abuse, and family history of suicide. Suicide prevention strategies in Nepal should account for the lack of awareness about suicide risk among family members and early age of suicide completion, especially in rural and female populations. Given the low rates of ideation disclosure to friends and family, educating the general public about other signs of suicide may help prevention efforts in Nepal.

  15. Recruitment strategies should not be randomly selected: empirically improving recruitment success and diversity in developmental psychology research

    Science.gov (United States)

    Sugden, Nicole A.; Moulson, Margaret C.

    2015-01-01

    Psychological and developmental research have been critiqued for the lack of diversity of research samples. Because differences in culture, race, and ethnicity can influence participant behavior, limited diversity limits the generalizability of the findings. These differences may also impact how participants behave in response to recruitment attempts, which suggests that recruitment itself may be leveraged to increase sample diversity. The goal of the current study was to determine what factors, within a recruitment interaction, could be leveraged to increase success and diversity when recruiting families with children for developmental research. Study 1 found three factors influenced success: (1) recruitment was more successful when other potential participants were also interested (i.e., recruiters were busy), (2) recruiters of particular races were more successful than recruiters of other races, and (3) differences in success were related to what the recruiter said to engage the potential participant (i.e., the script). The latter two factors interacted, suggesting some recruiters were using less optimal scripts. To improve success rates, study 2 randomly assigned scripts to recruiters and encouraged them to recruit more vigorously during busy periods. Study 2 found that two factors influenced success: (1) some scripts were more successful than others and (2) we were more successful at recruiting non-White potential participants than White participants. These two interacted, with some scripts being more successful with White and other scripts being more successful with non-White families. This intervention significantly increased recruitment success rate by 8.1% and the overall number of families recruited by 15.3%. These findings reveal that empirically evaluating and tailoring recruitment efforts based on the most successful strategies is effective in boosting diversity through increased participation of children from non-White families. PMID:25972829

  16. Recruitment strategies should not be randomly selected: empirically improving recruitment success and diversity in developmental psychology research.

    Science.gov (United States)

    Sugden, Nicole A; Moulson, Margaret C

    2015-01-01

    Psychological and developmental research have been critiqued for the lack of diversity of research samples. Because differences in culture, race, and ethnicity can influence participant behavior, limited diversity limits the generalizability of the findings. These differences may also impact how participants behave in response to recruitment attempts, which suggests that recruitment itself may be leveraged to increase sample diversity. The goal of the current study was to determine what factors, within a recruitment interaction, could be leveraged to increase success and diversity when recruiting families with children for developmental research. Study 1 found three factors influenced success: (1) recruitment was more successful when other potential participants were also interested (i.e., recruiters were busy), (2) recruiters of particular races were more successful than recruiters of other races, and (3) differences in success were related to what the recruiter said to engage the potential participant (i.e., the script). The latter two factors interacted, suggesting some recruiters were using less optimal scripts. To improve success rates, study 2 randomly assigned scripts to recruiters and encouraged them to recruit more vigorously during busy periods. Study 2 found that two factors influenced success: (1) some scripts were more successful than others and (2) we were more successful at recruiting non-White potential participants than White participants. These two interacted, with some scripts being more successful with White and other scripts being more successful with non-White families. This intervention significantly increased recruitment success rate by 8.1% and the overall number of families recruited by 15.3%. These findings reveal that empirically evaluating and tailoring recruitment efforts based on the most successful strategies is effective in boosting diversity through increased participation of children from non-White families.

  17. Recruitment strategies shouldn’t be randomly selected: Empirically improving recruitment success and diversity in developmental psychology research

    Directory of Open Access Journals (Sweden)

    Nicole Andrea Sugden

    2015-04-01

    Full Text Available Psychological and developmental research have been critiqued for the lack of diversity of research samples. Because differences in culture, race, and ethnicity can influence participant behavior, limited diversity limits the generalizability of the findings. These differences may also impact how participants behave in response to recruitment attempts, which suggests that recruitment itself may be leveraged to increase sample diversity. The goal of the current study was to determine what factors, within a recruitment interaction, could be leveraged to increase success and diversity when recruiting families with children for developmental research. Study 1 found three factors influenced success: 1 recruitment was more successful when other potential participants were also interested (i.e., recruiters were busy, 2 recruiters of particular races were more successful than recruiters of other races, and 3 differences in success were related to what the recruiter said to engage the potential participant (i.e., the script. The latter two factors interacted, suggesting some recruiters were using less optimal scripts. To improve success rates, study 2 randomly assigned scripts to recruiters and encouraged them to recruit more vigorously during busy periods. Study 2 found that two factors influenced success: 1 some scripts were more successful than others and 2 we were more successful at recruiting non-White potential participants than White participants. These two interacted, with some scripts being more successful with White and other scripts being more successful with non-White families. This intervention significantly increased recruitment success rate by 8.1% and the overall number of families recruited by 15.3%. These findings reveal that empirically evaluating and tailoring recruitment efforts based on the most successful strategies is effective in boosting diversity through increased participation of children from non-White families.

  18. Selection of single blastocysts for fresh transfer via standard morphology assessment alone and with array CGH for good prognosis IVF patients: results from a randomized pilot study

    Science.gov (United States)

    2012-01-01

    Background Single embryo transfer (SET) remains underutilized as a strategy to reduce multiple gestation risk in IVF, and its overall lower pregnancy rate underscores the need for improved techniques to select one embryo for fresh transfer. This study explored use of comprehensive chromosomal screening by array CGH (aCGH) to provide this advantage and improve pregnancy rate from SET. Methods First-time IVF patients with a good prognosis (age IVF program to select single blastocysts for fresh SET in good prognosis patients. The observed aneuploidy rate (44.9%) among biopsied blastocysts highlights the inherent imprecision of SET when conventional morphology is used alone. Embryos randomized to the aCGH group implanted with greater efficiency, resulted in clinical pregnancy more often, and yielded a lower miscarriage rate than those selected without aCGH. Additional studies are needed to verify our pilot data and confirm a role for on-site, rapid aCGH for IVF patients contemplating fresh SET. PMID:22551456

  19. 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.

  20. Comparison of community health worker-led diabetes medication decision-making support for low-income Latino and African American adults with diabetes using e-Health tools versus print materials: A randomized controlled trial

    Science.gov (United States)

    Heisler, Michele; Choi, Hwajung; Palmisano, Gloria; Mase, Rebecca; Richardson, Caroline; Fagerlin, Angela; Montori, Victor M.; Spencer, Michael; An, Laurence C.

    2015-01-01

    Background Health care centers serving low-income communities have scarce resources to support medication decision-making among patients with poorly controlled diabetes. Objective We compared outcomes between community health worker (CHW) use of a tailored, interactive web-based tablet-delivered tool (iDecide) versus use of print educational materials. Design A randomized two-arm trial from 2011-2013. Trial Registration NCT01427660. Setting Community health center in Detroit serving a Latino and African American low-income population. Participants 188 adults with a hemoglobinA1c >7.5% (55%) or who reported questions, concerns, or difficulty taking diabetes medications Primary Funding Sources Agency for Health Care Quality and Research (1R18HS019256-01) and P30DK092926 (MCDTR) Measurements Primary outcomes were changes in knowledge about anti-hyperglycemic medications, patient-reported medication decisional conflict, and satisfaction with anti-hyperglycemic medication information. We also examined changes in diabetes distress, self-efficacy, medication adherence, and A1c. Intervention Participants were randomized to receive a 1-2 hour session with a CHW using either iDecide or printed educational materials and two follow-up calls. Results 94% of participants completed three-month follow-up. Both groups improved across most measures. iDecide participants reported greater improvements in satisfaction with medication information (helpfulness, p=.007; clarity, p=.03) and in diabetes distress compared to the print materials group (pdetermine whether the greater improvements in satisfaction with medication information and diabetes distress achieved in the iDecide group at three months translate into better longer-term diabetes outcomes. PMID:25402398

  1. IGOB131, a novel seed extract of the West African plant Irvingia gabonensis, significantly reduces body weight and improves metabolic parameters in overweight humans in a randomized double-blind placebo controlled investigation

    Directory of Open Access Journals (Sweden)

    Mbofung Carl MF

    2009-03-01

    Full Text Available Abstract Background A recent in vitro study indicates that IGOB131, a novel seed extract of the traditional West African food plant Irvingia gabonensis, favorably impacts adipogenesis through a variety of critical metabolic pathways including PPAR gamma, leptin, adiponectin, and glycerol-3 phosphate dehydrogenase. This study was therefore aimed at evaluating the effects of IGOB131, an extract of Irvingia gabonensis, on body weight and associated metabolic parameters in overweight human volunteers. Methods The study participants comprised of 102 healthy, overweight and/or obese volunteers (defined as BMI > 25 kg/m2 randomly divided into two groups. The groups received on a daily basis, either 150 mg of IGOB131 or matching placebo in a double blinded fashion, 30–60 minutes before lunch and dinner. At baseline, 4, 8 and 10 weeks of the study, subjects were evaluated for changes in anthropometrics and metabolic parameters to include fasting lipids, blood glucose, C-reactive protein, adiponectin, and leptin. Results Significant improvements in body weight, body fat, and waist circumference as well as plasma total cholesterol, LDL cholesterol, blood glucose, C-reactive protein, adiponectin and leptin levels were observed in the IGOB131 group compared with the placebo group. Conclusion Irvingia gabonensis administered 150 mg twice daily before meals to overweight and/or obese human volunteers favorably impacts body weight and a variety of parameters characteristic of the metabolic syndrome. This is the first double blind randomized placebo controlled clinical trial regarding the anti-obesity and lipid profile modulating effects of an Irvingia gabonensis extract. The positive clinical results, together with our previously published mechanisms of gene expression modulation related to key metabolic pathways in lipid metabolism, provide impetus for much larger clinical studies. Irvingia gabonensis extract may prove to be a useful tool in dealing with the

  2. Quality of life and standard of living in a randomly selected group of psychiatrically disabled people in Sweden 2 years after a psychiatry reform.

    Science.gov (United States)

    Carlsson, I; Frederiksen, S-O; Gottfries, C-G

    2002-07-01

    In Sweden, a psychiatry reform, aimed at improving the living conditions of the psychiatrically disabled, came into force in 1995. The aim of the present study was to evaluate the impact of the reform by investigating quality of life and standard of living 2 years later in a randomly selected group of people with longstanding psychiatric disability. Self-ratings and interviews were conducted in a study group and a control group. The study group consisted of 19 women and 18 men (mean age 46.1 years) diagnosed with neurosis, schizophrenia or affective disorder. The control group consisted of 19 women and 17 men (mean age 48.7 years). Self-rated quality of life was significantly poorer in the study group (P standard of living in either group but a significant negative correlation in the control group (P standard of living.

  3. Effect of a Counseling Session Bolstered by Text Messaging on Self-Selected Health Behaviors in College Students: A Preliminary Randomized Controlled Trial.

    Science.gov (United States)

    Sandrick, Janice; Tracy, Doreen; Eliasson, Arn; Roth, Ashley; Bartel, Jeffrey; Simko, Melanie; Bowman, Tracy; Harouse-Bell, Karen; Kashani, Mariam; Vernalis, Marina

    2017-05-17

    The college experience is often the first time when young adults live independently and make their own lifestyle choices. These choices affect dietary behaviors, exercise habits, techniques to deal with stress, and decisions on sleep time, all of which direct the trajectory of future health. There is a need for effective strategies that will encourage healthy lifestyle choices in young adults attending college. This preliminary randomized controlled trial tested the effect of coaching and text messages (short message service, SMS) on self-selected health behaviors in the domains of diet, exercise, stress, and sleep. A second analysis measured the ripple effect of the intervention on health behaviors not specifically selected as a goal by participants. Full-time students aged 18-30 years were recruited by word of mouth and campuswide advertisements (flyers, posters, mailings, university website) at a small university in western Pennsylvania from January to May 2015. Exclusions included pregnancy, eating disorders, chronic medical diagnoses, and prescription medications other than birth control. Of 60 participants, 30 were randomized to receive a single face-to-face meeting with a health coach to review results of behavioral questionnaires and to set a health behavior goal for the 8-week study period. The face-to-face meeting was followed by SMS text messages designed to encourage achievement of the behavioral goal. A total of 30 control subjects underwent the same health and behavioral assessments at intake and program end but did not receive coaching or SMS text messages. The texting app showed that 87.31% (2187/2505) of messages were viewed by intervention participants. Furthermore, 28 of the 30 intervention participants and all 30 control participants provided outcome data. Among intervention participants, 22 of 30 (73%) showed improvement in health behavior goal attainment, with the whole group (n=30) showing a mean improvement of 88% (95% CI 39-136). Mean

  4. The effects of Nordic Walking training on selected upper-body muscle groups in female-office workers: A randomized trial.

    Science.gov (United States)

    Kocur, Piotr; Pospieszna, Barbara; Choszczewski, Daniel; Michalowski, Lukasz; Wiernicka, Marzena; Lewandowski, Jacek

    2017-01-01

    Regular Nordic Walking training could improve fitness and reduce tenderness in selected muscle groups in office workers. An assessment of the effects of a 12-week Nordic Walking training program on the perceived pain threshold (PPT) and the flexibility of selected upper-body muscle groups in postmenopausal female office workers. 39 office workers were selected at random for the treatment group (NWg, n = 20) and the control group (Cg, n = 19). The persons from the NW group completed a 12-week Nordic Walking training program (3 times a week/1 hour). PPTs measurements in selected muscles and functional tests evaluating upper-body flexibility (Back Scratch - BS) were carried out twice in every participant of the study: before and after the training program. A significant increase in PPT (kg/cm2) was observed in the following muscles in the NW group only: upper trapezius (from 1,32 kg/cm2 to 1,99 kg/cm2), mid trapezius (from 2,92 kg/cm2 to 3,30 kg/cm2), latissimus dorsi (from 1,66 kg/cm2 to 2,21 kg/cm2) and infraspinatus (from 1,63 kg/cm2 to 2,93 kg/cm2). Moreover, a significant improvement in the BS test was noted in the NW group compared with the control group (from -1,16±5,7 cm to 2,18±5,1 cm in the NW group vs from -2,52±6,1 to -2,92±6,2 in the control group). A 12-week Nordic Walking training routine improves shoulder mobility and reduces tenderness in the following muscles: trapezius pars descendens and middle trapezius, infraspinatus and latissimus dorsi, in female office workers.

  5. Zeta Sperm Selection Improves Pregnancy Rate and Alters Sex Ratio in Male Factor Infertility Patients: A Double-Blind, Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Nasr Esfahani Mohammad Hossein

    2016-07-01

    Full Text Available Background Selection of sperm for intra-cytoplasmic sperm injection (ICSI is usually considered as the ultimate technique to alleviate male-factor infertility. In routine ICSI, selection is based on morphology and viability which does not necessarily preclude the chance injection of DNA-damaged or apoptotic sperm into the oocyte. Sperm with high negative surface electrical charge, named “Zeta potential”, are mature and more likely to have intact chromatin. In addition, X-bearing spermatozoa carry more negative charge. Therefore, we aimed to compare the clinical outcomes of Zeta procedure with routine sperm selection in infertile men candidate for ICSI. Materials and Methods From a total of 203 ICSI cycles studied, 101 cycles were allocated to density gradient centrifugation (DGC/Zeta group and the remaining 102 were included in the DGC group in this prospective study. Clinical outcomes were com- pared between the two groups. The ratios of Xand Y bearing sperm were assessed by fluorescence in situ hybridization (FISH and quantitative polymerase chain reaction (qPCR methods in 17 independent semen samples. Results In the present double-blind randomized clinical trial, a significant increase in top quality embryos and pregnancy rate were observed in DGC/Zeta group compared to DGC group. Moreover, sex ratio (XY/XX at birth significantly was lower in the DGC/Zeta group compared to DGC group despite similar ratio of X/Y bearings sper- matozoa following Zeta selection. Conclusion Zeta method not only improves the percentage of top embryo quality and pregnancy outcome but also alters the sex ratio compared to the conventional DGC method, despite no significant change in the ratio of Xand Ybearing sperm population (Registration number: IRCT201108047223N1.

  6. A comparison of the effects of random and selective mass extinctions on erosion of evolutionary history in communities of digital organisms.

    Directory of Open Access Journals (Sweden)

    Gabriel Yedid

    Full Text Available The effect of mass extinctions on phylogenetic diversity and branching history of clades remains poorly understood in paleobiology. We examined the phylogenies of communities of digital organisms undergoing open-ended evolution as we subjected them to instantaneous "pulse" extinctions, choosing survivors at random, and to prolonged "press" extinctions involving a period of low resource availability. We measured age of the phylogenetic root and tree stemminess, and evaluated how branching history of the phylogenetic trees was affected by the extinction treatments. We found that strong random (pulse and strong selective extinction (press both left clear long-term signatures in root age distribution and tree stemminess, and eroded deep branching history to a greater degree than did weak extinction and control treatments. The widely-used Pybus-Harvey gamma statistic showed a clear short-term response to extinction and recovery, but differences between treatments diminished over time and did not show a long-term signature. The characteristics of post-extinction phylogenies were often affected as much by the recovery interval as by the extinction episode itself.

  7. A theory for the origin of a self-replicating chemical system. I - Natural selection of the autogen from short, random oligomers

    Science.gov (United States)

    White, D. H.

    1980-01-01

    A general theory is presented for the origin of a self-replicating chemical system, termed an autogen, which is capable of both crude replication and translation (protein synthesis). The theory requires the availability of free energy and monomers to the system, a significant background low-yield synthesis of kinetically stable oligopeptides and oligonucleotides, the localization of the oligomers, crude oligonucleotide selectivity of amino acids during oligopeptide synthesis, crude oligonucleotide replication, and two short peptide families which catalyze replication and translation, to produce a localized group of at least one copy each of two protogenes and two protoenzymes. The model posits a process of random oligomerization, followed by the random nucleation of functional components and the rapid autocatalytic growth of the functioning autogen to macroscopic amounts, to account for the origin of the first self-replicating system. Such a process contains steps of such high probability and short time periods that it is suggested that the emergence of an autogen in a laboratory experiment of reasonable time scale may be possible.

  8. Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial

    Science.gov (United States)

    Ballesteros, Soledad; Mayas, Julia; Prieto, Antonio; Ruiz-Marquez, Eloísa; Toril, Pilar; Reales, José M.

    2017-01-01

    Video game training with older adults potentially enhances aspects of cognition that decline with aging and could therefore offer a promising training approach. Although, previous published studies suggest that training can produce transfer, many of them have certain shortcomings. This randomized controlled trial (RCT; Clinicaltrials.gov ID: NCT02796508) tried to overcome some of these limitations by incorporating an active control group and the assessment of motivation and expectations. Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity, a commercial platform (http://www.lumosity.com/) or to an active control group trained for the same number of sessions with simulation strategy games. The final sample included 55 older adults (30 in the experimental group and 25 in the active control group). Participants were tested individually before and after training to assess working memory (WM) and selective attention and also reported their perceived improvement, motivation and engagement. The results showed improved performance across the training sessions. The main results were: (1) the experimental group did not show greater improvements in measures of selective attention and working memory than the active control group (the opposite occurred in the oddball task); (2) a marginal training effect was observed for the N-back task, but not for the Stroop task while both groups improved in the Corsi Blocks task. Based on these results, one can conclude that training with non-action games provide modest benefits for untrained tasks. The effect is not specific for that kind of training as a similar effect was observed for strategy video games. Groups did not differ in motivation, engagement or expectations. PMID:29163136

  9. Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial.

    Science.gov (United States)

    Ballesteros, Soledad; Mayas, Julia; Prieto, Antonio; Ruiz-Marquez, Eloísa; Toril, Pilar; Reales, José M

    2017-01-01

    Video game training with older adults potentially enhances aspects of cognition that decline with aging and could therefore offer a promising training approach. Although, previous published studies suggest that training can produce transfer, many of them have certain shortcomings. This randomized controlled trial (RCT; Clinicaltrials.gov ID: NCT02796508) tried to overcome some of these limitations by incorporating an active control group and the assessment of motivation and expectations. Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity, a commercial platform (http://www.lumosity.com/) or to an active control group trained for the same number of sessions with simulation strategy games. The final sample included 55 older adults (30 in the experimental group and 25 in the active control group). Participants were tested individually before and after training to assess working memory (WM) and selective attention and also reported their perceived improvement, motivation and engagement. The results showed improved performance across the training sessions. The main results were: (1) the experimental group did not show greater improvements in measures of selective attention and working memory than the active control group (the opposite occurred in the oddball task); (2) a marginal training effect was observed for the N-back task, but not for the Stroop task while both groups improved in the Corsi Blocks task. Based on these results, one can conclude that training with non-action games provide modest benefits for untrained tasks. The effect is not specific for that kind of training as a similar effect was observed for strategy video games. Groups did not differ in motivation, engagement or expectations.

  10. Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Soledad Ballesteros

    2017-11-01

    Full Text Available Video game training with older adults potentially enhances aspects of cognition that decline with aging and could therefore offer a promising training approach. Although, previous published studies suggest that training can produce transfer, many of them have certain shortcomings. This randomized controlled trial (RCT; Clinicaltrials.gov ID: NCT02796508 tried to overcome some of these limitations by incorporating an active control group and the assessment of motivation and expectations. Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity, a commercial platform (http://www.lumosity.com/ or to an active control group trained for the same number of sessions with simulation strategy games. The final sample included 55 older adults (30 in the experimental group and 25 in the active control group. Participants were tested individually before and after training to assess working memory (WM and selective attention and also reported their perceived improvement, motivation and engagement. The results showed improved performance across the training sessions. The main results were: (1 the experimental group did not show greater improvements in measures of selective attention and working memory than the active control group (the opposite occurred in the oddball task; (2 a marginal training effect was observed for the N-back task, but not for the Stroop task while both groups improved in the Corsi Blocks task. Based on these results, one can conclude that training with non-action games provide modest benefits for untrained tasks. The effect is not specific for that kind of training as a similar effect was observed for strategy video games. Groups did not differ in motivation, engagement or expectations.

  11. Genetic evaluation and selection response for growth in meat-type quail through random regression models using B-spline functions and Legendre polynomials.

    Science.gov (United States)

    Mota, L F M; Martins, P G M A; Littiere, T O; Abreu, L R A; Silva, M A; Bonafé, C M

    2017-08-14

    The objective was to estimate (co)variance functions using random regression models (RRM) with Legendre polynomials, B-spline function and multi-trait models aimed at evaluating genetic parameters of growth traits in meat-type quail. A database containing the complete pedigree information of 7000 meat-type quail was utilized. The models included the fixed effects of contemporary group and generation. Direct additive genetic and permanent environmental effects, considered as random, were modeled using B-spline functions considering quadratic and cubic polynomials for each individual segment, and Legendre polynomials for age. Residual variances were grouped in four age classes. Direct additive genetic and permanent environmental effects were modeled using 2 to 4 segments and were modeled by Legendre polynomial with orders of fit ranging from 2 to 4. The model with quadratic B-spline adjustment, using four segments for direct additive genetic and permanent environmental effects, was the most appropriate and parsimonious to describe the covariance structure of the data. The RRM using Legendre polynomials presented an underestimation of the residual variance. Lesser heritability estimates were observed for multi-trait models in comparison with RRM for the evaluated ages. In general, the genetic correlations between measures of BW from hatching to 35 days of age decreased as the range between the evaluated ages increased. Genetic trend for BW was positive and significant along the selection generations. The genetic response to selection for BW in the evaluated ages presented greater values for RRM compared with multi-trait models. In summary, RRM using B-spline functions with four residual variance classes and segments were the best fit for genetic evaluation of growth traits in meat-type quail. In conclusion, RRM should be considered in genetic evaluation of breeding programs.

  12. Implementing comprehensive prevention of mother-to-child transmission and HIV prevention for South African couples: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Jones, Deborah; Peltzer, Karl; Weiss, Stephen M; Sifunda, Sibusiso; Dwane, Ntabozuko; Ramlagan, Shandir; Cook, Ryan; Matseke, Gladys; Maduna, Vincent; Spence, Andrew

    2014-10-27

    In rural South Africa, only two-thirds of HIV-positive pregnant women seeking antenatal care at community health centers took full advantage of 'prevention of mother-to-child transmission' (PMTCT) services in 2010. Studies generally support male involvement to promote PMTCT, but the nature and impact of that involvement is unclear and untested. Additionally, stigma, disclosure and intimate partner violence pose significant barriers to PMTCT uptake and retention in care, suggesting that male involvement may be 'necessary, but not sufficient' to reduce infant HIV incidence. This study expands on a successful United States President's Emergency Plan for AIDS Relief (PEPFAR)-supported PMTCT couples intervention pilot study conducted in the Mpumalanga province, targeting HIV-positive pregnant women and their partners, the primary objective being to determine whether male partner involvement plus a behavioral intervention will significantly reduce infant HIV incidence. The study follows a cluster randomized controlled design enrolling two cohorts of HIV-positive pregnant women recruited from 12 randomly assigned Community Health Centers (CHC) (six experimental, six control). The two cohorts will consist of women attending without their male partners (n = 720) and women attending with their male partners (n = 720 couples), in order to determine whether the influence of male participation itself, or combined with a behavioral PMTCT intervention, can significantly reduce infant HIV infection ante-, peri- and postnatally. It is our intention to significantly increase PMTCT participation from current levels (69%) in the Mpumalanga province to between 90 and 95% through engaging women and couples in a controlled, six session ante- and postnatal risk-reducing and PMTCT promotion intervention addressing barriers to PMTCT (such as stigma, disclosure, intimate partner violence, communication, infant feeding practices and safer conception) that prevent women and men from utilizing

  13. Pesticides in South African fresh waters

    NARCIS (Netherlands)

    Ansara-Ross, T.; Wepener, V.; Brink, van den P.J.; Ross, M.J.

    2012-01-01

    Public concern has recently escalated over pesticide contamination of South African aquatic ecosystems. This review of published literature on the occurrence of pesticides within South African freshwater systems indicates that fewer than 50 studies of selected pesticides have been undertaken, with

  14. Long-chain PUFA supplementation in rural African infants: a randomized controlled trial of effects on gut integrity, growth, and cognitive development.

    Science.gov (United States)

    van der Merwe, Liandré F; Moore, Sophie E; Fulford, Anthony J; Halliday, Katherine E; Drammeh, Saikou; Young, Stephen; Prentice, Andrew M

    2013-01-01

    Intestinal damage and malabsorption caused by chronic environmental enteropathy are associated with growth faltering seen in infants in less-developed countries. Evidence has suggested that supplementary omega-3 (n-3) long-chain PUFAs (LC-PUFAs) might ameliorate this damage by reducing gastrointestinal inflammation. LC-PUFA supplementation may also benefit cognitive development. We tested whether early n-3 LC-PUFA supplementation improves infant intestinal integrity, growth, and cognitive function. A randomized, double-blind, controlled trial [200 mg DHA and 300 mg EPA or 2 mL olive oil/d for 6 mo] was conducted in a population of 172 rural Gambian infants aged 3-9 mo. The primary endpoints were anthropometric measures and gut integrity [assessed by using urinary lactulose:mannitol ratios (LMRs)]. Plasma fatty acid status, intestinal mucosal inflammation (fecal calprotectin), daily morbidity, and cognitive development (2-step means-end test and an attention assessment) were secondary endpoints. PUFA supplementation resulted in a significant increase in plasma n-3 LC-PUFA concentrations (P development. The trial was registered at www.isrctn.org as ISRCTN66645725.

  15. HPV SEROSTATUS PRE- AND POST-VACCINATION IN A RANDOMIZED PHASE II PREPAREDNESS TRIAL AMONG YOUNG WESTERN CAPE, SOUTH AFRICAN WOMEN: THE EVRI TRIAL.

    Science.gov (United States)

    Sudenga, Staci L; Torres, B Nelson; Botha, Matthys H; Zeier, Michele; Abrahamsen, Martha E; Glashoff, Richard H; Engelbrecht, Susan; Schim Van der Loeff, Maarten F; Van der Laan, Louvina E; Kipping, Siegfried; Taylor, Douglas; Giuliano, Anna R

    2017-06-01

    HPV antibodies are a marker of past exposure to the virus. Our objective was to assess HPV serostatus pre- and post-vaccination among HIV-negative women. Women aged 16-24 years old were randomized in a placebo controlled trial utilizing the 4-valent HPV (4vHPV) vaccine (NCT01489527, clinicaltrials.gov). Participants (n=389) received the 4vHPV vaccine or placebo following a three dose schedule. Sera were collected at Day 1 and Month 7 for assessment of HPV 6, 11, 16, and 18 neutralizing antibody levels using a multiplex competitive Luminex immunoassay (Merck) based on detecting the L1 capsid antigen for each HPV type. Seroprevalence was 73% for HPV6, 47% for HPV11, 33% for HPV16, and 44% for HPV18. Seroprevalence for any HPV type did not significantly differ by age or lifetime number of partners. The majority of participants (64%) had two or more 4vHPV antibodies present at enrollment and 12% had antibodies to all four. Among women in the vaccine arm, those that were seropositive for HPV16 at enrollment had higher titers at month 7 compared to women that were seronegative for HPV16 at enrollment; this trend holds for the other HPV types as well. Seroconversion among baseline seronegative participants in the placebo group ranged from 5% for HPV16 to 23% for HPV6. HPV seroprevalence was high in this population, emphasizing the need to vaccinate prior to sexual debut.

  16. n-3 Long-chain PUFAs reduce respiratory morbidity caused by iron supplementation in iron-deficient South African schoolchildren: a randomized, double-blind, placebo-controlled intervention.

    Science.gov (United States)

    Malan, Linda; Baumgartner, Jeannine; Calder, Philip C; Zimmermann, Michael B; Smuts, Cornelius M

    2015-03-01

    Although iron supplementation in malaria-free areas mostly reduces infectious morbidity, it can sometimes increase morbidity from infections as a result of the dependence of pathogenic microorganisms on iron. Supplementation with n-3 (ω-3) long-chain polyunsaturated fatty acids (LCPUFAs) improved morbidity in several human studies. However, information on the combined effect of iron and n-3 LCPUFA supplementation on infectious morbidity is limited. We determined whether n-3 LCPUFAs and iron supplementation, alone or in combination, affected absenteeism and illness in iron-deficient schoolchildren with low fish intake. A total of 321 South African children (aged 6-11 y) with iron deficiency (ID) were randomly divided into 4 groups to receive 1) iron plus placebo, 2) a mixture of docosahexaenoic acid and eicosapentaenoic acid (DHA/EPA) plus placebo, 3) iron plus DHA/EPA, or 4) placebo plus placebo as oral supplements 4 times/wk for 8.5 mo. Morbidity was recorded, and iron-status indexes were measured. The total phospholipid fatty acid composition of peripheral blood mononuclear cell membranes was analyzed in a subsample (n = 130). Iron supplementation increased the number of days with illness when all symptoms were considered (B: 0.87; 95% CI: 0.71, 1.03) as well as illness that was specifically caused by respiratory symptoms (B: 1.45; 95% CI: 1.21, 1.70), whereas DHA/EPA reduced the number of days with illness at school (B: -0.96; 95% CI: -1.33, -0.59). The increases caused by iron were reduced to the levels seen in the placebo plus placebo group when iron was provided in combination with DHA/EPA as indicated by significant iron × DHA/EPA interactions (both P morbidity (mostly respiratory) in iron-deficient South African schoolchildren with low DHA/EPA intake, but when iron was given in combination with DHA/EPA, this effect was prevented. © 2015 American Society for Nutrition.

  17. African Environment

    African Journals Online (AJOL)

    Environmental Studies and Regional Planning Bulletin African Environment is published in French and English, and for some issues, in Arabic. (only the issue below has been received by AJOL). Vol 10, No 3 (1999). DOWNLOAD FULL TEXT Open Access DOWNLOAD FULL TEXT Subscription or Fee Access. Table of ...

  18. A randomized controlled trial investigating the use of a predictive nomogram for the selection of the FSH starting dose in IVF/ICSI cycles.

    Science.gov (United States)

    Allegra, Adolfo; Marino, Angelo; Volpes, Aldo; Coffaro, Francesco; Scaglione, Piero; Gullo, Salvatore; La Marca, Antonio

    2017-04-01

    The number of oocytes retrieved is a relevant intermediate outcome in women undergoing IVF/intracytoplasmic sperm injection (ICSI). This trial compared the efficiency of the selection of the FSH starting dose according to a nomogram based on multiple biomarkers (age, day 3 FSH, anti-Müllerian hormone) versus an age-based strategy. The primary outcome measure was the proportion of women with an optimal number of retrieved oocytes defined as 8-14. At their first IVF/ICSI cycle, 191 patients underwent a long gonadotrophin-releasing hormone agonist protocol and were randomized to receive a starting dose of recombinant (human) FSH, based on their age (150 IU if ≤35 years, 225 IU if >35 years) or based on the nomogram. Optimal response was observed in 58/92 patients (63%) in the nomogram group and in 42/99 (42%) in the control group (+21%, 95% CI = 0.07 to 0.35, P = 0.0037). No significant differences were found in the clinical pregnancy rate or the number of embryos cryopreserved per patient. The study showed that the FSH starting dose selected according to ovarian reserve is associated with an increase in the proportion of patients with an optimal response: large trials are recommended to investigate any possible effect on the live-birth rate. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  19. Considerations for preparing a randomized population health intervention trial: lessons from a South African-Canadian partnership to improve the health of health workers.

    Science.gov (United States)

    Yassi, Annalee; O'Hara, Lyndsay Michelle; Engelbrecht, Michelle C; Uebel, Kerry; Nophale, Letshego Elizabeth; Bryce, Elizabeth Ann; Buxton, Jane A; Siegel, Jacob; Spiegel, Jerry Malcolm

    2014-12-01

    Background Community-based cluster-randomized controlled trials (RCTs) are increasingly being conducted to address pressing global health concerns. Preparations for clinical trials are well-described, as are the steps for multi-component health service trials. However, guidance is lacking for addressing the ethical and logistic challenges in (cluster) RCTs of population health interventions in low- and middle-income countries. Objective We aimed to identify the factors that population health researchers must explicitly consider when planning RCTs within North-South partnerships. Design We reviewed our experiences and identified key ethical and logistic issues encountered during the pre-trial phase of a recently implemented RCT. This trial aimed to improve tuberculosis (TB) and Human Immunodeficiency Virus (HIV) prevention and care for health workers by enhancing workplace assessment capability, addressing concerns about confidentiality and stigma, and providing onsite counseling, testing, and treatment. An iterative framework was used to synthesize this analysis with lessons taken from other studies. Results The checklist of critical factors was grouped into eight categories: 1) Building trust and shared ownership; 2) Conducting feasibility studies throughout the process; 3) Building capacity; 4) Creating an appropriate information system; 5) Conducting pilot studies; 6) Securing stakeholder support, with a view to scale-up; 7) Continuously refining methodological rigor; and 8) Explicitly addressing all ethical issues both at the start and continuously as they arise. Conclusion Researchers should allow for the significant investment of time and resources required for successful implementation of population health RCTs within North-South collaborations, recognize the iterative nature of the process, and be prepared to revise protocols as challenges emerge.

  20. Prevalence of at-risk genotypes for genotoxic effects decreases with age in a randomly selected population in Flanders: a cross sectional study

    Directory of Open Access Journals (Sweden)

    van Delft Joost HM

    2011-10-01

    Full Text Available Abstract Background We hypothesized that in Flanders (Belgium, the prevalence of at-risk genotypes for genotoxic effects decreases with age due to morbidity and mortality resulting from chronic diseases. Rather than polymorphisms in single genes, the interaction of multiple genetic polymorphisms in low penetrance genes involved in genotoxic effects might be of relevance. Methods Genotyping was performed on 399 randomly selected adults (aged 50-65 and on 442 randomly selected adolescents. Based on their involvement in processes relevant to genotoxicity, 28 low penetrance polymorphisms affecting the phenotype in 19 genes were selected (xenobiotic metabolism, oxidative stress defense and DNA repair, respectively 13, 6 and 9 polymorphisms. Polymorphisms which, based on available literature, could not clearly be categorized a priori as leading to an 'increased risk' or a 'protective effect' were excluded. Results The mean number of risk alleles for all investigated polymorphisms was found to be lower in the 'elderly' (17.0 ± 2.9 than the 'adolescent' (17.6 ± 3.1 subpopulation (P = 0.002. These results were not affected by gender nor smoking. The prevalence of a high (> 17 = median number of risk alleles was less frequent in the 'elderly' (40.6% than the 'adolescent' (51.4% subpopulation (P = 0.002. In particular for phase II enzymes, the mean number of risk alleles was lower in the 'elderly' (4.3 ± 1.6 than the 'adolescent' age group (4.8 ± 1.9 P 4 = median number of risk alleles was less frequent in the 'elderly' (41.3% than the adolescent subpopulation (56.3%, P 8 = median number of risk alleles for DNA repair enzyme-coding genes was lower in the 'elderly' (37,3% than the 'adolescent' subpopulation (45.6%, P = 0.017. Conclusions These observations are consistent with the hypothesis that, in Flanders, the prevalence of at-risk alleles in genes involved in genotoxic effects decreases with age, suggesting that persons carrying a higher number of

  1. The WORD (Wholeness, Oneness, Righteousness, Deliverance): design of a randomized controlled trial testing the effectiveness of an evidence-based weight loss and maintenance intervention translated for a faith-based, rural, African American population using a community-based participatory approach.

    Science.gov (United States)

    Yeary, Karen Hye-cheon Kim; Cornell, Carol E; Prewitt, Elaine; Bursac, Zoran; Tilford, J Mick; Turner, Jerome; Eddings, Kenya; Love, ShaRhonda; Whittington, Emily; Harris, Kimberly

    2015-01-01

    The positive effects of weight loss on obesity-related risk factors diminish unless weight loss is maintained. Yet little work has focused on the translation of evidence-based weight loss interventions with the aim of sustaining weight loss in underserved populations. Using a community-based participatory approach (CBPR) that engages the strong faith-based social infrastructure characteristic of rural African American communities is a promising way to sustain weight loss in African Americans, who bear a disproportionate burden of the obesity epidemic. Led by a collaborative community-academic partnership, The WORD aims to change dietary and physical activity behaviors to produce and maintain weight loss in rural, African American adults of faith. The WORD is a randomized controlled trial with 450 participants nested within 30 churches. All churches will receive a 16-session core weight loss intervention. Half of the churches will be randomized to receive an additional 12-session maintenance component. The WORD is a cultural adaptation of the Diabetes Prevention Program, whereby small groups will be led by trained church members. Participants will be assessed at baseline, 6, 12, and 18 months. A detailed cost-effectiveness and process evaluation will be included. The WORD aims to sustain weight loss in rural African Americans. The utilization of a CBPR approach and the engagement of the faith-based social infrastructure of African American communities will maximize the intervention's sustainability. Unique aspects of this trial include the focus on weight loss maintenance and the use of a faith-based CBPR approach in translating evidence-based obesity interventions. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Exposure to lead in South African shooting ranges.

    Science.gov (United States)

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

    2017-02-01

    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. An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. 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 ≥10μg/dl (pShooting 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. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Technological properties of Lactobacillus fermentum involved in the processing of dolo and pito, West African sorghum beers, for the selection of starter cultures

    DEFF Research Database (Denmark)

    Sawadogo-Lingani, H.; Diawara, B.; Traoré, A.S.

    2008-01-01

    AIM: Technological properties of Lactobacillus fermentum isolates involved in spontaneous fermentation of dolo and pito wort were examined to select starter cultures. METHODS AND RESULTS: 264 isolates were screened for antimicrobial activity, acidifying activity, exopolysaccharides (EPSs) and amy...

  4. Mellonee Burnim on African American Music.

    Science.gov (United States)

    Campbell, Patricia Shehan

    1995-01-01

    Describes the role and influence of Mellonee Burnim on U.S. music education. Discusses the origins and impact of African American gospel music. Includes a list of selected resources and two lesson plans featuring gospel music. (CFR)

  5. An African Scholars Perspective

    African Journals Online (AJOL)

    Toshiba

    Abstract. The transformation of the Organization of African Unity to African. Union is a historical landmark of African Leaders' intention towards integration, project her continental interest in the international state system and seek for African initiative in solving African problems. This paper seeks to strengthen the operations of ...

  6. African Journals Online (AJOL)

    African Journals Online (AJOL)

    ChemSearch Journal. Vol 48, No 3 (2018). South African Journal of Animal Science. Vol 8, No 1 (2018). African Journal of Chemical Education. Vol 48, No 2 (2018). South African Journal of Animal Science. Vol 48, No 1 (2018). South African Journal of Animal Science. Vol 7, No 1 (2018). South African Journal of Geomatics.

  7. The African elephants' toe nails | Parker | Journal of East African ...

    African Journals Online (AJOL)

    Journal of East African Natural History. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 106, 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 load here ...

  8. Prevention of Breast Cancer in African women | Okonofua | African ...

    African Journals Online (AJOL)

    African Journal of Reproductive Health. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 10, 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 ...

  9. Ensemble of random forests One vs. Rest classifiers for MCI and AD prediction using ANOVA cortical and subcortical feature selection and partial least squares.

    Science.gov (United States)

    Ramírez, J; Górriz, J M; Ortiz, A; Martínez-Murcia, F J; Segovia, F; Salas-Gonzalez, D; Castillo-Barnes, D; Illán, I A; Puntonet, C G

    2017-12-11

    Alzheimer's disease (AD) is the most common cause of dementia in the elderly and affects approximately 30 million individuals worldwide. Mild cognitive impairment (MCI) is very frequently a prodromal phase of AD, and existing studies have suggested that people with MCI tend to progress to AD at a rate of about 10-15% per year. However, the ability of clinicians and machine learning systems to predict AD based on MRI biomarkers at an early stage is still a challenging problem that can have a great impact in improving treatments. The proposed system, developed by the SiPBA-UGR team for this challenge, is based on feature standardization, ANOVA feature selection, partial least squares feature dimension reduction and an ensemble of One vs. Rest random forest classifiers. With the aim of improving its performance when discriminating healthy controls (HC) from MCI, a second binary classification level was introduced that reconsiders the HC and MCI predictions of the first level. The system was trained and evaluated on an ADNI datasets that consist of T1-weighted MRI morphological measurements from HC, stable MCI, converter MCI and AD subjects. The proposed system yields a 56.25% classification score on the test subset which consists of 160 real subjects. The classifier yielded the best performance when compared to: (i) One vs. One (OvO), One vs. Rest (OvR) and error correcting output codes (ECOC) as strategies for reducing the multiclass classification task to multiple binary classification problems, (ii) support vector machines, gradient boosting classifier and random forest as base binary classifiers, and (iii) bagging ensemble learning. A robust method has been proposed for the international challenge on MCI prediction based on MRI data. The system yielded the second best performance during the competition with an accuracy rate of 56.25% when evaluated on the real subjects of the test set. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Monitoring Results in Routine Immunization: Development of Routine Immunization Dashboard in Selected African Countries in the Context of the Polio Eradication Endgame Strategic Plan.

    Science.gov (United States)

    Poy, Alain; van den Ent, Maya M V X; Sosler, Stephen; Hinman, Alan R; Brown, Sidney; Sodha, Samir; Ehlman, Daniel C; Wallace, Aaron S; Mihigo, Richard

    2017-07-01

    To monitor immunization-system strengthening in the Polio Eradication Endgame Strategic Plan 2013-2018 (PEESP), the Global Polio Eradication Initiative identified 1 indicator: 10% annual improvement in third dose of diphtheria- tetanus-pertussis-containing vaccine (DTP3) coverage in polio high-risk districts of 10 polio focus countries. A multiagency team, including staff from the African Region, developed a comprehensive list of outcome and process indicators measuring various aspects of the performance of an immunization system. The development and implementation of the dashboard to assess immunization system performance allowed national program managers to monitor the key immunization indicators and stratify by high-risk and non-high-risk districts. Although only a single outcome indicator goal (at least 10% annual increase in DTP3 coverage achieved in 80% of high-risk districts) initially existed in the endgame strategy, we successfully added additional outcome indicators (eg, decreasing the number of DTP3-unvaccinated children) as well as program process indicators focusing on cold chain, stock availability, and vaccination sessions to better describe progress on the pathway to raising immunization coverage. When measuring progress toward improving immunization systems, it is helpful to use a comprehensive approach that allows for measuring multiple dimensions of the system.

  11. Improvisation in West African Musics.

    Science.gov (United States)

    Locke, David

    1980-01-01

    Discussed is music of the sub-Sahara. Vocal, instrumental, and dance drumming from the Sudan Desert, the North Coast, East Horn, Central and West Africa, and contrapuntal yodeling of Pygmies is described. For African musicians, the ability to improvise, and creativity, are gifts from God. Includes selected readings and recordings. (KC)

  12. 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 ...

  13. 604 EAST AFRICAN MEDICAL JOURNAL

    African Journals Online (AJOL)

    2001-11-01

    Nov 1, 2001 ... Indian South Africans in genes associated with bone mineral density and osteoporosis. Design: Genes selected were the vitamin D receptor (Apa I and Taq I polymorphisms) and collagen (Sp I transcription factor polymorphism) using standard molecular biology techniques. Setting: Department of Chemical ...

  14. 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.

  15. 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

    Introduction 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. Methods 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. Results 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). Conclusions 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. PMID:25862565

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

    Directory of Open Access Journals (Sweden)

    Mona Loutfy

    2015-04-01

    Full Text Available Introduction: 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. Methods: 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. Results: 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. Conclusions: 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.

  17. 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 ...

  18. 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 ... Featured Country: Uganda, Featured Journal: African Crop Science Journal. Most recent issues on AJOL: Vol 34, No 3 (2017).

  19. 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 ... Featured Country: Ghana, Featured Journal: Ghana Journal of Science. Most recent issues on AJOL: Vol 34, No 3 (2017). African ...

  20. 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 ...

  1. Rock magnetic evidence of non-random raw material selection criteria in Cerro Toledo Obsidian Artifacts from Valles Caldera, New Mexico

    Science.gov (United States)

    Gregovich, A.; Feinberg, J. M.; Steffen, A.; Sternberg, R. S.

    2014-12-01

    Stone tools are one of the most enduring forms of ancient human behavior available to anthropologists. The geologic materials that comprise stone tools are a reflection of the rocks that were available locally or through trade, as are the intended use of the tools and the knapping technology needed to produce them. Investigation of the rock magnetic and geochemical characteristics of the artifacts and the geological source materials provides a baseline to explore these past behaviors. This study uses rock magnetic properties to explore the raw material selection criteria involved in the production of obsidian tools in the region around Valles Caldera in northern New Mexico. Obsidian is locally abundant and was traded by tribes across the central United States. Here we compare the rock magnetic properties of a sample of obsidian projectile points (N =25) that have been geochemically sourced to the Cerro Toledo obsidian flow with geological samples collected from four sites within the same flow (N =135). This collection of archaeological artifacts, albeit small, contains representatives of at least 8 different point styles that were used over 6000 years from the Archaic into the Late Prehistoric. Bulk rock hysteresis parameters (Mr, Ms, Bc, and Bcr) and low-field susceptibility (Χ) measurements show that the projectile points generally contain a lower concentration of magnetic minerals than the geologic samples. For example, the artifacts' median Ms value is 2.9 x 10-3 Am2kg-1, while that of the geological samples is 6.5 x 10-3 Am2kg-1. The concentration of magnetic minerals in obsidian is a proxy for the concentration of microlites in general, and this relationship suggests that although obsidian was locally abundant, toolmakers employed non-random selection criteria resulting in generally lower concentrations of microlites in their obsidian tools.

  2. Radiofrequency catheter selection based on cavotricuspid angiography compared with a control group with an externally cooled-tip catheter: a randomized pilot study.

    Science.gov (United States)

    Da Costa, Antoine; Romeyer-Bouchard, Cécile; Jamon, Yann; Bisch, Laurence; Isaaz, Karl

    2009-05-01

    Radiofrequency ablation (RFA) of cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) can be performed using either externally cooled-tip RFA catheters or large-tip (8 mm) catheters. However, experimental and clinical studies suggest that the efficacy of both catheters may vary with CTI anatomy and catheters orientation. The aim of this prospective study was to evaluate: a RFA catheter selection based on CTI angiography compared with a control group with an externally cooled-tip catheter together with the risk of an expensive crossover catheter in both groups. Over a period of 16 months, 119 patients were included and randomized. When comparing the angiographic group (n = 56) and the externally cooled-tip RFA catheter group (n = 63), the duration of application time with a median of 7 min (interquartile range 4.5-11) versus a median of 10 min (interquartile range 6-20; P = 0.008) and the duration of X-ray exposure with a median of 7 min (interquartile range 4-10) versus a median of 10 min (interquartile range 5-15; P = 0.025) were significantly lower in the angiographic group versus externally cooled-tip catheter group. Furthermore, the number of catheters crossover was significantly higher in the angiographic group versus externally cooled-tip catheter group I (27% vs 7%; P = 0.007). This study shows that a strategy with a catheter selection based on a CTI angiographic evaluation is superior to an empirical use of an externally cooled-tip catheter during CTI RFA. Thus, angiographic isthmus evaluation predicts the effectiveness of a RFA catheter and the risk of an expensive catheter crossover.

  3. Comparative Evolutionary Histories of the Fungal Chitinase Gene Family Reveal Non-Random Size Expansions and Contractions due to Adaptive Natural Selection

    Directory of Open Access Journals (Sweden)

    Jan Stenlid

    2008-01-01

    Full Text Available Gene duplication and loss play an important role in the evolution of novel functions and for shaping an organism’s gene content. Recently, it was suggested that stress-related genes frequently are exposed to duplications and losses, while growth-related genes show selection against change in copy number. The fungal chitinase gene family constitutes an interesting case study of gene duplication and loss, as their biological roles include growth and development as well as more stress-responsive functions. We used genome sequence data to analyze the size of the chitinase gene family in different fungal taxa, which range from 1 in Batrachochytrium dendrobatidis and Schizosaccharomyces pombe to 20 in Hypocrea jecorina and Emericella nidulans, and to infer their phylogenetic relationships. Novel chitinase subgroups are identified and their phylogenetic relationships with previously known chitinases are discussed. We also employ a stochastic birth and death model to show that the fungal chitinase gene family indeed evolves non-randomly, and we identify six fungal lineages where larger-than-expected expansions (Pezizomycotina, H. jecorina, Gibberella zeae, Uncinocarpus reesii, E. nidulans and Rhizopus oryzae, and two contractions (Coccidioides immitis and S. pombe potentially indicate the action of adaptive natural selection. The results indicate that antagonistic fungal-fungal interactions are an important process for soil borne ascomycetes, but not for fungal species that are pathogenic in humans. Unicellular growth is correlated with a reduction of chitinase gene copy numbers which emphasizes the requirement of the combined action of several chitinases for filamentous growth.

  4. Selected 20th and 21st century representations of tribalism and modernity in South African literature: reassessing socio-historical process through (reconsiderations of works of verbal art

    Directory of Open Access Journals (Sweden)

    Annie Gagiano

    2011-10-01

    Full Text Available http://dx.doi.org/10.5007/2175-8026.2011n61p037 Opening with a brief historical contextualisation, the article takes the reader back to humanity’s prehistoric origins in southern Africa, then to its (and mankind’s earliest known culture, that of the San/Bushmen, followed by the (returning migrations of Khoikhoi and Bantu peoples to the area. Usings even literary texts, discussed in their order of composition, the article discusses these evocations as representing a spectrum of ways in which regional tribal cultures were, are or may be seen.The Khoikhoi elder Hendrik’s tale, told as well as transcribedin Afrikaans [now available in an English translation], is the first text; it addresses the ability of a tribal culture to correct aleader’s power abuse by means of verbal art and skill. Secondly, the great Xhosa poet S. E. K. Mqhayi’s advocation of a balance between tribal and Christian values is addressed, followed by Bessie Head’s critique of women’s denigration, seen as facilitated by Batswana tribal and modern cultures. Lauretta Ngcobo in her second novel evokes a dignified rural black woman’s struggles with the exclusionary and oppressive effects of both apartheid and Zulu tribal customs, while Zakes Mda’s novel achieves a wise and ironically tinged balance in depicting tribal traditionalism and modernity in a Xhosa village. David Donald’s is a delicately empathetic evocation of a dwindling Bushman culture besetby both white and black incursions in early colonial times, while (lastly the essay considers the recent novel by Thando Mgqolozana which warns, in a devastating account, of the physical and psychological harm effected by the deteriorating practice of circumcision of young males among the AmaXhosa. This mosaic of texts establishes the strengths as well as the dangers of a range of southern African tribal cultures over arange of time and in different settings.

  5. Cross-Sectional Analysis of Selected Genital Tract Immunological Markers and Molecular Vaginal Microbiota in Sub-Saharan African Women, with Relevance to HIV Risk and Prevention.

    Science.gov (United States)

    Kyongo, Jordan K; Crucitti, Tania; Menten, Joris; Hardy, Liselotte; Cools, Piet; Michiels, Johan; Delany-Moretlwe, Sinead; Mwaura, Mary; Ndayisaba, Gilles; Joseph, Sarah; Fichorova, Raina; van de Wijgert, Janneke; Vanham, Guido; Ariën, Kevin K; Jespers, Vicky

    2015-05-01

    Data on immune mediators in the genital tract and the factors that modulate them in sub-Saharan women are limited. Cervicovaginal lavage (CVL) samples from 430 sexually active women from Kenya, South Africa, and Rwanda were analyzed for 12 soluble immune mediators using Bio-Plex and Meso Scale Discovery multiplex platforms, as well as single enzyme-linked immunosorbent assays. Ten bacterial species were quantified in vaginal swab samples. Bacterial vaginosis (BV) was defined by Nugent scoring. CVL samples from HIV-infected women showed a clear-cut proinflammatory profile. Pregnant women, adolescents, and women engaging in traditional vaginal practices differed in specific soluble markers compared to reference groups of adult HIV-negative women. Cervical mucus, cervical ectopy, abnormal vaginal discharge, and having multiple sex partners were each associated with an increase in inflammatory mediators. The levels of interleukin-1α (IL-1α), IL-1β, IL-6, IL-12(p70), and IL-8 were elevated, whereas the IL-1RA/IL-1(α+β) ratio decreased in women with BV. The level of gamma interferon-induced protein 10 was lower in BV-positive than in BV-negative women, suggesting its suppression as a potential immune evasion mechanism by BV-associated bacteria. Lactobacillus crispatus and Lactobacillus vaginalis were associated with decreased proinflammatory cytokines and each BV-associated species with increased proinflammatory cytokines. Remarkably, the in vitro anti-HIV activity of CVL samples from BV-positive women was stronger than that of BV-negative women. In conclusion, we found significant associations of factors, including vaginal microbiota, which can influence immune mediators in the vaginal environment in sexually active women. These factors need to be considered when establishing normative levels or pathogenic cutoffs of biomarkers of inflammation and associated risks in African women. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. Exploration of the Hypothalamic-Pituitary-Adrenal Axis to Improve Animal Welfare by Means of Genetic Selection: Lessons from the South African Merino

    Directory of Open Access Journals (Sweden)

    Schalk Cloete

    2013-05-01

    Full Text Available It is a difficult task to improve animal production by means of genetic selection, if the environment does not allow full expression of the animal’s genetic potential. This concept may well be the future for animal welfare, because it highlights the need to incorporate traits related to production and robustness, simultaneously, to reach sustainable breeding goals. This review explores the identification of potential genetic markers for robustness within the hypothalamic-pituitary-adrenal axis (HPAA, since this axis plays a vital role in the stress response. If genetic selection for superior HPAA responses to stress is possible, then it ought to be possible to breed robust and easily managed genotypes that might be able to adapt to a wide range of environmental conditions whilst expressing a high production potential. This approach is explored in this review by means of lessons learnt from research on Merino sheep, which were divergently selected for their multiple rearing ability. These two selection lines have shown marked differences in reproduction, production and welfare, which makes this breeding programme ideal to investigate potential genetic markers of robustness. The HPAA function is explored in detail to elucidate where such genetic markers are likely to be found.

  7. Are Africans, Europeans, and Asians Different "Races"? A Guided-Inquiry Lab for Introducing Undergraduate Students to Genetic Diversity and Preparing Them to Study Natural Selection

    Science.gov (United States)

    Kalinowski, Steven T.; Andrews, Tessa M.; Leonard, Mary J.; Snodgrass, Meagan

    2012-01-01

    Many students do not recognize that individual organisms within populations vary, and this may make it difficult for them to recognize the essential role variation plays in natural selection. Also, many students have weak scientific reasoning skills, and this makes it difficult for them to recognize misconceptions they might have. This paper…

  8. The Impact of Early Literacy and Behavior Sanctions on African-American Male High School Students' Matriculation in a Selected South Carolina School District

    Science.gov (United States)

    Fitzpatrick, Raashad

    2012-01-01

    The study under investigation was the impact of early literacy and behavior sanctions on Black male matriculation towards graduation in a selected South Carolina school district. Attendance and course failure in English strongly predicted whether or not students graduated from high school. Early literacy is the foundation for academic success in…

  9. African Solutions to African Problems?

    DEFF Research Database (Denmark)

    Emmanuel, Nikolas G.; Schwartz, Brendan

    2017-01-01

    . The emergence of Déby’s Chad depends both on its ability to accomplish sub-imperial tasks encouraged by these actors, while obfuscating undemocratic governance and human rights abuses at home. Nonetheless, Déby’s role in regional security has helped him achieve a certain degree of agency in his relationship......—tenuous position at home and abroad. Chad is the current representation of the hackneyed phrase, “African solutions to African problems”. However, one must not forget that Chad’s meteoric rise has been facilitated by important states in the international system, mainly France but also the United States...... of apparently competing liberal and illiberal interests. This will lead us to a better explanation of Déby’s recent rise at home and abroad....

  10. Unruptured intracranial aneurysms: their illusive natural history and why subgroup statistics cannot provide normative criteria for clinical decisions or selection criteria for a randomized trial.

    Science.gov (United States)

    Raymond, J; Roy, D; Weill, A; Guilbert, F; Nguyen, T; Molyneux, A J; Fox, A J; Johnston, S C; Cognard, C; Pierot, L; Meder, J-F; Rouleau, Isabelle

    2008-10-01

    There is currently no evidence that treatment of unruptured aneurysms is beneficial. Confronted with the uncertainty, many clinicians are attracted by an individual calculus of risks using numbers extracted from subgroup statistics of observational studies or natural history data. The so-called natural history of unruptured aneurysms refers to a purely man-made ratio of events divided by the number of untreated patients identified by imaging, a ratio heavily influenced by referral patterns and arbitrary clinical decisions. Available studies lacked prespecified hypotheses, exposing all analyses to sampling error and bias, and sample sizes were too small to provide reliable subgroup statistics. Far from being "natural kinds" of aneurysms, subgroups were post-hoc creations. Resulting data-driven statistics can only be exploratory, the error too uncontrollable to serve for clinical decisions. A randomized trial is in order, but selection according to fixed size criteria is ill-advised, given the imprecision of imaging, the influence of other factors such as location, previous history, multiplicity of lesions, risks of treatment, age and the danger of arbitrarily excluding from a long trial a large segment of the population with aneurysms for whom the research question is most pertinent.

  11. Early prevention of antisocial personality: long-term follow-up of two randomized controlled trials comparing indicated and selective approaches.

    Science.gov (United States)

    Scott, Stephen; Briskman, Jackie; O'Connor, Thomas G

    2014-06-01

    Antisocial personality is a common adult problem that imposes a major public health burden, but for which there is no effective treatment. Affected individuals exhibit persistent antisocial behavior and pervasive antisocial character traits, such as irritability, manipulativeness, and lack of remorse. Prevention of antisocial personality in childhood has been advocated, but evidence for effective interventions is lacking. The authors conducted two follow-up studies of randomized trials of group parent training. One involved 120 clinic-referred 3- to 7-year-olds with severe antisocial behavior for whom treatment was indicated, 93 of whom were reassessed between ages 10 and 17. The other involved 109 high-risk 4- to 6-year-olds with elevated antisocial behavior who were selectively screened from the community, 90 of whom were reassessed between ages 9 and 13. The primary psychiatric outcome measures were the two elements of antisocial personality, namely, antisocial behavior (assessed by a diagnostic interview) and antisocial character traits (assessed by a questionnaire). Also assessed were reading achievement (an important domain of youth functioning at work) and parent-adolescent relationship quality. In the indicated sample, both elements of antisocial personality were improved in the early intervention group at long-term follow-up compared with the control group (antisocial behavior: odds ratio of oppositional defiant disorder=0.20, 95% CI=0.06, 0.69; antisocial character traits: B=-4.41, 95% CI=-1.12, -8.64). Additionally, reading ability improved (B=9.18, 95% CI=0.58, 18.0). Parental expressed emotion was warmer (B=0.86, 95% CI=0.20, 1.41) and supervision was closer (B=-0.43, 95% CI=-0.11, -0.75), but direct observation of parenting showed no differences. Teacher-rated and self-rated antisocial behavior were unchanged. In contrast, in the selective high-risk sample, early intervention was not associated with improved long-term outcomes. Early intervention with

  12. Selection of single blastocysts for fresh transfer via standard morphology assessment alone and with array CGH for good prognosis IVF patients: results from a randomized pilot study

    Directory of Open Access Journals (Sweden)

    Yang Zhihong

    2012-05-01

    Full Text Available Abstract Background Single embryo transfer (SET remains underutilized as a strategy to reduce multiple gestation risk in IVF, and its overall lower pregnancy rate underscores the need for improved techniques to select one embryo for fresh transfer. This study explored use of comprehensive chromosomal screening by array CGH (aCGH to provide this advantage and improve pregnancy rate from SET. Methods First-time IVF patients with a good prognosis (age Results For patients in Group A (n = 55, 425 blastocysts were biopsied and analyzed via aCGH (7.7 blastocysts/patient. Aneuploidy was detected in 191/425 (44.9% of blastocysts in this group. For patients in Group B (n = 48, 389 blastocysts were microscopically examined (8.1 blastocysts/patient. Clinical pregnancy rate was significantly higher in the morphology + aCGH group compared to the morphology-only group (70.9 and 45.8%, respectively; p = 0.017; ongoing pregnancy rate for Groups A and B were 69.1 vs. 41.7%, respectively (p = 0.009. There were no twin pregnancies. Conclusion Although aCGH followed by frozen embryo transfer has been used to screen at risk embryos (e.g., known parental chromosomal translocation or history of recurrent pregnancy loss, this is the first description of aCGH fully integrated with a clinical IVF program to select single blastocysts for fresh SET in good prognosis patients. The observed aneuploidy rate (44.9% among biopsied blastocysts highlights the inherent imprecision of SET when conventional morphology is used alone. Embryos randomized to the aCGH group implanted with greater efficiency, resulted in clinical pregnancy more often, and yielded a lower miscarriage rate than those selected without aCGH. Additional studies are needed to verify our pilot data and confirm a role for on-site, rapid aCGH for IVF patients contemplating fresh SET.

  13. Population diversity and antibody selective pressure to Plasmodium falciparum MSP1 block2 locus in an African malaria-endemic setting

    Directory of Open Access Journals (Sweden)

    Trape Jean-François

    2009-10-01

    Full Text Available Abstract Background Genetic evidence for diversifying selection identified the Merozoite Surface Protein1 block2 (PfMSP1 block2 as a putative target of protective immunity against Plasmodium falciparum. The locus displays three family types and one recombinant type, each with multiple allelic forms differing by single nucleotide polymorphism as well as sequence, copy number and arrangement variation of three amino acid repeats. The family-specific antibody responses observed in endemic settings support immune selection operating at the family level. However, the factors contributing to the large intra-family allelic diversity remain unclear. To address this question, population allelic polymorphism and sequence variant-specific antibody responses were studied in a single Senegalese rural community where malaria transmission is intense and perennial. Results Family distribution showed no significant temporal fluctuation over the 10 y period surveyed. Sequencing of 358 PCR fragments identified 126 distinct alleles, including numerous novel alleles in each family and multiple novel alleles of recombinant types. The parasite population consisted in a large number of low frequency alleles, alongside one high-frequency and three intermediate frequency alleles. Population diversity tests supported positive selection at the family level, but showed no significant departure from neutrality when considering intra-family allelic sequence diversity and all families combined. Seroprevalence, analysed using biotinylated peptides displaying numerous sequence variants, was moderate and increased with age. Reactivity profiles were individual-specific, mapped to the family-specific flanking regions and to repeat sequences shared by numerous allelic forms within a family type. Seroreactivity to K1-, Mad20- and R033 families correlated with the relative family genotype distribution within the village. Antibody specificity remained unchanged with cumulated exposure

  14. Estimating the hypothetical dual health impact and cost-effectiveness of the Woman’s Condom in selected sub-Saharan African countries

    Directory of Open Access Journals (Sweden)

    Mvundura M

    2015-03-01

    Full Text Available Mercy Mvundura, Neeti Nundy, Maggie Kilbourne-Brook, Patricia S Coffey Technology Solutions Global Program, PATH, Seattle, WA, USA Background: Female condoms are the only currently available woman-initiated option that offers dual protection from pregnancy and sexually transmitted infections, including HIV. The Woman’s Condom is a new female condom designed to provide dual protection and to be highly pleasurable and acceptable. Objective: We sought to estimate the potential dual health impact and cost-effectiveness of a Woman’s Condom distribution program in 13 sub-Saharan African countries with HIV prevalence rates >4% among adults aged 15–49 years. We used two separate, publicly available models for this analysis, the Impact 2 model developed by Marie Stopes International and the Population Services International disability-adjusted life years (DALY calculator program. We estimated the potential numbers of pregnancies and DALYs averted when the Woman’s Condom is used as a family planning method and the HIV infections and DALYs averted when it is used as an HIV prevention method. Results: Programming 100,000 Woman’s Condoms in each of 13 countries in sub-Saharan Africa during a 1-year period could potentially prevent 194 pregnancies and an average of 21 HIV infections in each country. When using the World Health Organization CHOosing Interventions that are Cost-Effective (WHO-CHOICE criteria as a threshold to infer the potential cost-effectiveness of the Woman’s Condom, we found that the Woman’s Condom would be considered cost-effective. Conclusion: This was a first and successful attempt to estimate the impact of dual protection of female condoms. The health impact is greater for the use of the Woman’s Condom as an HIV prevention method than for contraception. Dual use of the Woman’s Condom increases the overall health impact. The Woman’s Condom was found to be very cost-effective in all 13 countries in our sample. Keywords

  15. In vitro selection of Plasmodium falciparum 3D7 for expression of variant surface antigens associated with severe malaria in African children

    DEFF Research Database (Denmark)

    Staalsoe, Trine; Nielsen, Morten A; Vestergaard, Lasse S

    2003-01-01

    . Parasites isolated from young children with severe malaria (SM) tend to express a limited and conserved set of VSA (VSASM) that are both stronger and more commonly recognized by IgG in the plasma of malaria-exposed individuals than VSA (VSAUM) expressed by parasites causing uncomplicated malaria (UM...... and epidemiologically diverse areas of endemic parasite transmission. The described selection method appears a useful tool in the identification of genes encoding VSA involved in severe and life-threatening P. falciparum malaria....

  16. Environmental ethics: An African understanding | Ojomo | African ...

    African Journals Online (AJOL)

    Environmental ethics: An African understanding. ... African Journal of Environmental Science and Technology ... Abstract. Global concerns about the current environmental crisis have culminated into some controversial environmental ethical theories, that is, normative environmental ethics, sentientist ethics, biocentric ethics, ...

  17. Generic-reference and generic-generic bioequivalence of forty-two, randomly-selected, on-market generic products of fourteen immediate-release oral drugs.

    Science.gov (United States)

    Hammami, Muhammad M; De Padua, Sophia J S; Hussein, Rajaa; Al Gaai, Eman; Khodr, Nesrine A; Al-Swayeh, Reem; Alvi, Syed N; Binhashim, Nada

    2017-12-08

    The extents of generic-reference and generic-generic average bioequivalence and intra-subject variation of on-market drug products have not been prospectively studied on a large scale. We assessed bioequivalence of 42 generic products of 14 immediate-release oral drugs with the highest number of generic products on the Saudi market. We conducted 14 four-sequence, randomized, crossover studies on the reference and three randomly-selected generic products of amlodipine, amoxicillin, atenolol, cephalexin, ciprofloxacin, clarithromycin, diclofenac, ibuprofen, fluconazole, metformin, metronidazole, paracetamol, omeprazole, and ranitidine. Geometric mean ratios of maximum concentration (Cmax) and area-under-the-concentration-time-curve, to last measured concentration (AUCT), extrapolated to infinity (AUCI), or truncated to Cmax time of reference product (AUCReftmax) were calculated using non-compartmental method and their 90% confidence intervals (CI) were compared to the 80.00%-125.00% bioequivalence range. Percentages of individual ratios falling outside the ±25% range were also determined. Mean (SD) age and body-mass-index of 700 healthy volunteers (28-80/study) were 32.2 (6.2) years and 24.4 (3.2) kg/m2, respectively. In 42 generic-reference comparisons, 100% of AUCT and AUCI CIs showed bioequivalence, 9.5% of Cmax CIs barely failed to show bioequivalence, and 66.7% of AUCReftmax CIs failed to show bioequivalence/showed bioinequivalence. Adjusting for 6 comparisons, 2.4% of AUCT and AUCI CIs and 21.4% of Cmax CIs failed to show bioequivalence. In 42 generic-generic comparisons, 2.4% of AUCT, AUCI, and Cmax CIs failed to show bioequivalence, and 66.7% of AUCReftmax CIs failed to show bioequivalence/showed bioinequivalence. Adjusting for 6 comparisons, 2.4% of AUCT and AUCI CIs and 14.3% of Cmax CIs failed to show bioequivalence. Average geometric mean ratio deviation from 100% was ≤3.2 and ≤5.4 percentage points for AUCI and Cmax, respectively, in both generic

  18. Efficacy of aerobic exercise and a prudent diet for improving selected lipids and lipoproteins in adults: a meta-analysis of randomized controlled trials

    Directory of Open Access Journals (Sweden)

    Roberts Susan

    2011-06-01

    Full Text Available Abstract Background Studies addressing the effects of aerobic exercise and a prudent diet on lipid and lipoprotein concentrations in adults have reached conflicting conclusions. The purpose of this study was to determine the effects of aerobic exercise combined with a prudent diet on lipid and lipoprotein concentrations in adults. Methods Studies were located by searching nine electronic databases, cross-referencing, and expert review. Two independent reviewers selected studies that met the following criteria: (1 randomized controlled trials, (2 aerobic exercise combined with diet recommendations (saturated/trans fat intake less than 10% of total calories and cholesterol less than 300 mg/day and/or fiber intake ≥25 g/day in women and ≥35 grams per day in men, (3 intervention ≥4 weeks, (4 humans ≥18 years of age, (5 published studies, including dissertations and Master's theses, (6 studies published in any language, (7 studies published between January 1, 1955 and May 1, 2009, (8 assessment of one or more of the following lipid and lipoprotein concentrations: total cholesterol (TC, high-density lipoprotein cholesterol (HDL-C, ratio of TC to HDL-C, non-HDL-C, low-density lipoprotein cholesterol (LDL-C and triglycerides (TG. Two reviewers independently extracted all data. Random-effects models that account for heterogeneity and 95% confidence intervals were used to pool findings. Results Of the 1,401 citations reviewed, six studies representing 16 groups (8 intervention, 8 control and up to 559 men and women (282 intervention, 277 control met the criteria for analysis. Statistically significant intervention minus control reductions were found for TC (-15.5 mg/dl, 95% CI, -20.3 to -10.7, TC:HDL-C (-0.4 mg/dl, 95% CI, -0.7 to -0.2, LDL-C (-9.2 mg/dl, 95% CI, -12.7 to -5.8 and TG (-10.6 mg/dl, 95% CI, -17.2 to -4.0 but not HDL-C (-0.5 mg/dl, 95% CI, -4.0 to 3.1. Changes were equivalent to reductions of 7.5%, 6.6%, 7.2% and 18.2% respectively

  19. South African Journal of African Languages

    African Journals Online (AJOL)

    The South African Journal of African Languages is a peer-reviewed research journal devoted to the advancement of African (Bantu) and Khoe-San languages and literatures. Papers, book reviews and polemic contributions of a scientific nature in any of the core areas of linguistics, both theoretical (e.g. syntax, phonology, ...

  20. Efficacy and Safety of the RTS,S/AS01 Malaria Vaccine during 18 Months after Vaccination: A Phase 3 Randomized, Controlled Trial in Children and Young Infants at 11 African Sites

    Science.gov (United States)

    2014-01-01

    Background A malaria vaccine could be an important addition to current control strategies. We report the safety and vaccine efficacy (VE) of the RTS,S/AS01 vaccine during 18 mo following vaccination at 11 African sites with varying malaria transmission. Methods and Findings 6,537 infants aged 6–12 wk and 8,923 children aged 5–17 mo were randomized to receive three doses of RTS,S/AS01 or comparator vaccine. VE against clinical malaria in children during the 18 mo after vaccine dose 3 (per protocol) was 46% (95% CI 42% to 50%) (range 40% to 77%; VE, pvaccine dose 1 (intention to treat [ITT]) was 45% (95% CI 41% to 49%). VE against severe malaria, malaria hospitalization, and all-cause hospitalization was 34% (95% CI 15% to 48%), 41% (95% CI 30% to 50%), and 19% (95% CI 11% to 27%), respectively (ITT). VE against clinical malaria in infants was 27% (95% CI 20% to 32%, per protocol; 27% [95% CI 21% to 33%], ITT), with no significant protection against severe malaria, malaria hospitalization, or all-cause hospitalization. Post-vaccination anti-circumsporozoite antibody geometric mean titer varied from 348 to 787 EU/ml across sites in children and from 117 to 335 EU/ml in infants (per protocol). VE waned over time in both age categories (Schoenfeld residuals pmalaria cases averted per 1,000 children vaccinated ranged across sites from 37 to 2,365 and from −1 to 49, respectively; corresponding ranges among infants were −10 to 1,402 and −13 to 37, respectively (ITT). Meningitis was reported as a serious adverse event in 16/5,949 and 1/2,974 children and in 9/4,358 and 3/2,179 infants in the RTS,S/AS01 and control groups, respectively. Conclusions RTS,S/AS01 prevented many cases of clinical and severe malaria over the 18 mo after vaccine dose 3, with the highest impact in areas with the greatest malaria incidence. VE was higher in children than in infants, but even at modest levels of VE, the number of malaria cases averted was substantial. RTS,S/AS01 could be an

  1. Is self-assessment of medical abortion using a low-sensitivity pregnancy test combined with a checklist and phone text messages feasible in South African primary healthcare settings? A randomized trial.

    Directory of Open Access Journals (Sweden)

    Deborah Constant

    Full Text Available To evaluate feasibility of self-assessment of medical abortion outcome using a low-sensitivity urine pregnancy test, checklist and text messages. The study assessed whether accurate self-assessment required a demonstration of the low-sensitivity urine pregnancy test or if verbal instructions suffice.This non-inferiority trial enrolled 525 adult women from six public sector abortion clinics. Eligible women were undergoing medical abortion at gestations within 63 days. Consenting women completed a baseline interview, received standard care with mifepristone and home-administration of misoprostol. All were given a low-sensitivity urine pregnancy test and checklist for use 14 days later, sent text reminders, and asked to attend in-clinic follow-up after two weeks. Women were randomly assigned 1:1 to an instruction-only group (n = 262; issued with pre-scripted instructions on the low-sensitivity pregnancy test, or a demonstration group (n = 263; performed practice tests guided by lay health workers. The primary outcome was accurate self-assessment of incomplete abortion, defined as needing additional misoprostol or vacuum aspiration. Analysis was by intention to treat and a non-inferiority margin was set to six percentage points. Women's acceptability of their abortion procedure and preferences for follow-up were also assessed.Follow-up was 81% for abortion outcome, confirmed in-clinic at two weeks or self-reported within six months. Non-inferiority of instruction-only to a demonstration was inconclusive for accurate self-assessment (risk difference for instruction-only -demonstration: -2.5%; 95%CI: -9% to 4%. Comparing instruction-only to demonstration groups, 99% and 100% found the pregnancy test easy to do; and 91% and 93% respectively chose the pregnancy test, checklist and text messages for abortion outcome assessment in the future.Routine self-assessment using a low-sensitivity pregnancy test, checklist and text messages is feasible and

  2. Impact of acyclovir on genital and plasma HIV-1 RNA, genital herpes simplex virus type 2 DNA, and ulcer healing among HIV-1-infected African women with herpes ulcers: a randomized placebo-controlled trial.

    Science.gov (United States)

    Mayaud, Philippe; Legoff, Jérôme; Weiss, Helen A; Grésenguet, Gérard; Nzambi, Khonde; Bouhlal, Hicham; Frost, Eric; Pépin, Jacques; Malkin, Jean-Elie; Hayes, Richard J; Mabey, David C W; Bélec, Laurent

    2009-07-15

    Little is known about the impact of episodic treatment of herpes on human immunodeficiency virus type 1 (HIV-1). Women from Ghana and the Central African Republic who had genital ulcers were enrolled in a randomized, double-blind, placebo-controlled trial of acyclovir plus antibacterials and were monitored for 28 days. Ulcer etiologies and detection of lesional HIV-1 RNA were determined by polymerase chain reaction (PCR). Cervicovaginal HIV-1 RNA and herpes simplex virus type 2 (HSV-2) DNA and plasma HIV-1 RNA were quantitated by real-time PCR. Primary analyses included 118 HIV-1-infected women with HSV-2 ulcers (54 of whom were given acyclovir and 64 of whom were given placebo). Acyclovir had little impact on (1) detection of cervicovaginal HIV-1 RNA (risk ratio [RR], 0.96; 95% confidence interval [CI], 0.8-1.2) at day 7 of treatment, (2) the mean cervicovaginal HIV-1 RNA load (-0.06 log(10) copies/mL; 95% CI, -0.4 to 0.3 log(10) copies/mL) at day 7 of treatment, or (3) the plasma HIV-1 RNA load (+0.09 log(10) copies/mL; 95% CI, -0.1 to 0.3 log(10) copies/mL) at day 14 of treatment. At day 7, women receiving acyclovir were less likely to have detectable lesional HIV-1 RNA (RR, 0.70; 95% CI, 0.4-1.2) or cervicovaginal HSV-2 DNA (RR, 0.69; 95% CI, 0.4-1.3), had a lower quantity of HSV-2 DNA (-0.99 log(10) copies/mL; 95% CI, -1.8 to -0.2 log(10) copies/mL), and were more likely to have a healed ulcer (RR, 1.26; 95% CI, 0.9-1.9). Episodic therapy for herpes reduced the quantity of cervicovaginal HSV-2 DNA and slightly improved ulcer healing, but it did not decrease genital and plasma HIV-1 RNA loads. ClinicalTrials.gov identifier NCT00158483 .

  3. Is self-assessment of medical abortion using a low-sensitivity pregnancy test combined with a checklist and phone text messages feasible in South African primary healthcare settings? A randomized trial.

    Science.gov (United States)

    Constant, Deborah; Harries, Jane; Daskilewicz, Kristen; Myer, Landon; Gemzell-Danielsson, Kristina

    2017-01-01

    To evaluate feasibility of self-assessment of medical abortion outcome using a low-sensitivity urine pregnancy test, checklist and text messages. The study assessed whether accurate self-assessment required a demonstration of the low-sensitivity urine pregnancy test or if verbal instructions suffice. This non-inferiority trial enrolled 525 adult women from six public sector abortion clinics. Eligible women were undergoing medical abortion at gestations within 63 days. Consenting women completed a baseline interview, received standard care with mifepristone and home-administration of misoprostol. All were given a low-sensitivity urine pregnancy test and checklist for use 14 days later, sent text reminders, and asked to attend in-clinic follow-up after two weeks. Women were randomly assigned 1:1 to an instruction-only group (n = 262; issued with pre-scripted instructions on the low-sensitivity pregnancy test), or a demonstration group (n = 263; performed practice tests guided by lay health workers). The primary outcome was accurate self-assessment of incomplete abortion, defined as needing additional misoprostol or vacuum aspiration. Analysis was by intention to treat and a non-inferiority margin was set to six percentage points. Women's acceptability of their abortion procedure and preferences for follow-up were also assessed. Follow-up was 81% for abortion outcome, confirmed in-clinic at two weeks or self-reported within six months. Non-inferiority of instruction-only to a demonstration was inconclusive for accurate self-assessment (risk difference for instruction-only -demonstration: -2.5%; 95%CI: -9% to 4%). Comparing instruction-only to demonstration groups, 99% and 100% found the pregnancy test easy to do; and 91% and 93% respectively chose the pregnancy test, checklist and text messages for abortion outcome assessment in the future. Routine self-assessment using a low-sensitivity pregnancy test, checklist and text messages is feasible and preferred by women

  4. Sequence based prediction of DNA-binding proteins based on hybrid feature selection using random forest and Gaussian naïve Bayes.

    Directory of Open Access Journals (Sweden)

    Wangchao Lou

    Full Text Available Developing an efficient method for determination of the DNA-binding proteins, due to their vital roles in gene regulation, is becoming highly desired since it would be invaluable to advance our understanding of protein functions. In this study, we proposed a new method for the prediction of the DNA-binding proteins, by performing the feature rank using random forest and the wrapper-based feature selection using forward best-first search strategy. The features comprise information from primary sequence, predicted secondary structure, predicted relative solvent accessibility, and position specific scoring matrix. The proposed method, called DBPPred, used Gaussian naïve Bayes as the underlying classifier since it outperformed five other classifiers, including decision tree, logistic regression, k-nearest neighbor, support vector machine with polynomial kernel, and support vector machine with radial basis function. As a result, the proposed DBPPred yields the highest average accuracy of 0.791 and average MCC of 0.583 according to the five-fold cross validation with ten runs on the training benchmark dataset PDB594. Subsequently, blind tests on the independent dataset PDB186 by the proposed model trained on the entire PDB594 dataset and by other five existing methods (including iDNA-Prot, DNA-Prot, DNAbinder, DNABIND and DBD-Threader were performed, resulting in that the proposed DBPPred yielded the highest accuracy of 0.769, MCC of 0.538, and AUC of 0.790. The independent tests performed by the proposed DBPPred on completely a large non-DNA binding protein dataset and two RNA binding protein datasets also showed improved or comparable quality when compared with the relevant prediction methods. Moreover, we observed that majority of the selected features by the proposed method are statistically significantly different between the mean feature values of the DNA-binding and the non DNA-binding proteins. All of the experimental results indicate that

  5. The CAP study, evaluation of integrated universal and selective prevention strategies for youth alcohol misuse: study protocol of a cluster randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Newton Nicola C

    2012-08-01

    Full Text Available Abstract Background Alcohol misuse amongst young people is a serious concern. The need for effective prevention is clear, yet there appear to be few evidenced-based programs that prevent alcohol misuse and none that target both high and low-risk youth. The CAP study addresses this gap by evaluating the efficacy of an integrated approach to alcohol misuse prevention, which combines the effective universal internet-based Climate Schools program with the effective selective personality-targeted Preventure program. This article describes the development and protocol of the CAP study which aims to prevent alcohol misuse and related harms in Australian adolescents. Methods/Design A cluster randomized controlled trial (RCT is being conducted with Year 8 students aged 13 to 14-years-old from 27 secondary schools in New South Wales and Victoria, Australia. Blocked randomisation was used to assign schools to one of four groups; Climate Schools only, Preventure only, CAP (Climate Schools and Preventure, or Control (alcohol, drug and health education as usual. The primary outcomes of the trial will be the uptake and harmful use of alcohol and alcohol related harms. Secondary outcomes will include alcohol and cannabis related knowledge, cannabis related harms, intentions to use, and mental health symptomatology. All participants will complete assessments on five occasions; baseline; immediately post intervention, and at 12, 24 and 36 months post baseline. Discussion This study protocol presents the design and current implementation of a cluster RCT to evaluate the efficacy of the CAP study; an integrated universal and selective approach to prevent alcohol use and related harms among adolescents. Compared to students who receive the stand-alone universal Climate Schools program or alcohol and drug education as usual (Controls, we expect the students who receive the CAP intervention to have significantly less uptake of alcohol use, a reduction in average

  6. 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 ...

  7. Effects of local storage practices on deterioration of African eggplant ...

    African Journals Online (AJOL)

    The objective of this study was to evaluate the influence of postharvest storage practices on shelf life of African eggplant fruits based on decay and water losses. A laboratory experiment was laid out in a split plot arrangement following a complete randomized block design with three replications. Three African eggplant ...

  8. Impact of amoxicillin therapy on resistance selection in patients with community-acquired lower respiratory tract infections: a randomized, placebo-controlled study.

    Science.gov (United States)

    Malhotra-Kumar, Surbhi; Van Heirstraeten, Liesbet; Coenen, Samuel; Lammens, Christine; Adriaenssens, Niels; Kowalczyk, Anna; Godycki-Cwirko, Maciek; Bielicka, Zuzana; Hupkova, Helena; Lannering, Christina; Mölstad, Sigvard; Fernandez-Vandellos, Patricia; Torres, Antoni; Parizel, Maxim; Ieven, Margareta; Butler, Chris C; Verheij, Theo; Little, Paul; Goossens, Herman

    2016-11-01

    To determine the effect of amoxicillin treatment on resistance selection in patients with community-acquired lower respiratory tract infections in a randomized, placebo-controlled trial. Patients were prescribed amoxicillin 1 g, three times daily (n = 52) or placebo (n = 50) for 7 days. Oropharyngeal swabs obtained before, within 48 h post-treatment and at 28-35 days were assessed for proportions of amoxicillin-resistant (ARS; amoxicillin MIC ≥2 mg/L) and -non-susceptible (ANS; MIC ≥0.5 mg/L) streptococci. Alterations in amoxicillin MICs and in penicillin-binding-proteins were also investigated. ITT and PP analyses were conducted. ARS and ANS proportions increased 11- and 2.5-fold, respectively, within 48 h post-amoxicillin treatment compared with placebo [ARS mean increase (MI) 9.46, 95% CI 5.57-13.35; ANS MI 39.87, 95% CI 30.96-48.78; P  0.1588). ARS/ANS were grouped by pbp mutations. Group 1 strains exhibited significantly lower amoxicillin resistance (mean MIC 2.8 mg/L, 95% CI 2.6-3.1) than group 2 (mean MIC 9.3 mg/L, 95% CI 8.1-10.5; P amoxicillin is modest and short-lived, probably due to 'fitness costs' engendered by high-level resistance-conferring mutations. This evidence further supports European guidelines that recommend amoxicillin when an antibiotic is indicated for community-acquired lower respiratory tract infections. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.

  9. Acne RA-1,2, a novel UV-selective face cream for patients with acne: Efficacy and tolerability results of a randomized, placebo-controlled clinical study.

    Science.gov (United States)

    Cestone, Enza; Michelotti, Angela; Zanoletti, Valentina; Zanardi, Andrea; Mantegazza, Raffaella; Dossena, Maurizia

    2017-06-01

    General skincare measures such as the use of moisturisers and products containing adequate photoprotection are important components of acne patients' management to complement the pharmacological regimen. Acne RA-1,2 is a novel dermato-cosmetic product which contains selective photofilters and active ingredients against the multifactorial pathophysiology of acne. To evaluate the tolerability of Acne RA-1,2 and its effect on the clinical signs of acne. This double-blind, placebo-controlled study randomized 40 adult patients with 10-25 comedones per half face to once-daily application of Acne RA-1,2 or placebo for 8 weeks. Evaluations after 4 and 8 weeks included the number of comedones, transepidermal water loss (TEWL), sebum production, and tolerability. In the Acne RA-1,2 group, there was a significant 35% decrease in the mean number of comedones from 26 at baseline to 17 at Week 8 (P<.001), a 7% significant reduction in TEWL (9.32 to 8.66 g/h/m(2) ; P<.001), and a 24% significant reduction in sebum production (154.8 to 117.6 μg/cm(2) ; P<.001). The reductions in TEWL and sebum production were significantly greater than those in the placebo group at Weeks 4 and 8 (P<0.05). There were no adverse events. Acne RA-1,2 was well tolerated and effective at reducing comedones and sebum production and improving epidermal barrier function. These results suggest that Acne RA-1,2 is useful against acne-prone facial skin, particularly as it targets sebum production, which topical pharmacological acne therapies do not address. © 2017 Wiley Periodicals, Inc.

  10. An assessment of the quality of care for children in eighteen randomly selected district and sub-district hospitals in Bangladesh

    Directory of Open Access Journals (Sweden)

    Hoque Dewan ME

    2012-12-01

    Full Text Available Abstract Background Quality hospital care is important in ensuring that the needs of severely ill children are met to avert child mortality. However, the quality of hospital care for children in developing countries has often been found poor. As the first step of a country road map for improving hospital care for children, we assessed the baseline situation with respect to the quality of care provided to children under-five years age in district and sub-district level hospitals in Bangladesh. Methods Using adapted World Health Organization (WHO hospital assessment tools and standards, an assessment of 18 randomly selected district (n=6 and sub-district (n=12 hospitals was undertaken. Teams of trained assessors used direct case observation, record review, interviews, and Management Information System (MIS data to assess the quality of clinical case management and monitoring; infrastructure, processes and hospital administration; essential hospital and laboratory supports, drugs and equipment. Results Findings demonstrate that the overall quality of care provided in these hospitals was poor. No hospital had a functioning triage system to prioritise those children most in need of immediate care. Laboratory supports and essential equipment were deficient. Only one hospital had all of the essential drugs for paediatric care. Less than a third of hospitals had a back-up power supply, and just under half had functioning arrangements for safe-drinking water. Clinical case management was found to be sub-optimal for prevalent illnesses, as was the quality of neonatal care. Conclusion Action is needed to improve the quality of paediatric care in hospital settings in Bangladesh, with a particular need to invest in improving newborn care.

  11. African Communalism and Globalization

    African Journals Online (AJOL)

    info

    Abstract. The certainty of African philosophy during pre-colonial Africa is no longer in doubt. Doubting such a claim is denying the existence of the African race which may be self contradictory. As this work observes, African philosophy which is all encompassing, is inbuilt in African communalism through which indigenous ...

  12. African Journals Online: Estonia

    African Journals Online (AJOL)

    PROMOTING ACCESS TO AFRICAN RESEARCH. AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL · RESOURCES. African Journals Online: Estonia. Home > African Journals Online: Estonia. Log in or Register to get access to full text downloads. Username, Password, Remember me

  13. African Journals Online: Ireland

    African Journals Online (AJOL)

    PROMOTING ACCESS TO AFRICAN RESEARCH. AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL · RESOURCES. African Journals Online: Ireland. Home > African Journals Online: Ireland. Log in or Register to get access to full text downloads. Username, Password, Remember me

  14. 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 a Non-Profit Organisation based in ...

  15. Conversation on African Music.

    Science.gov (United States)

    Saunders, Leslie R.

    1985-01-01

    A voice and music education teacher at the University of Lagos, Nigeria, talks about African music in this interview. Topics discussed include differences between African and Western music, African melody, rules for composing African music, the theory of counterpoint, and the popularity of classical composers in Nigeria. (RM)

  16. 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 ... Southern African Business Review; Conflicts in Africa: Meaning, Causes, Impact and Solution African Research Review; The abnormal ...

  17. African Journals Online (AJOL)

    African Journals Online (AJOL)

    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 a Non-Profit Organisation based in South ... South African Journal of Animal Science. Vol 59, No 5 (2017). South African Family ...

  18. African Journals Online (AJOL)

    African Journals Online (AJOL)

    African Research Review; The competitive advantage of nations: is Porter's Diamond Framework a new theory that explains the international competitiveness of countries? Southern African Business Review; The Rise of Independent African Churches, 1890-1930: An Ethical-genesis of Nigerian Nationalism African ...

  19. 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.

  20. African Journals Online (AJOL)

    African Journals Online (AJOL)

    Journal of Research in Forestry, Wildlife and Environment. Vol 8, No 2 (2016). African Review of Economics and Finance. Vol 8, No 1 (2016). African Review of Economics and Finance. Vol 9, No 1 (2017). African Review of Economics and Finance. Vol 16, No 2 (2016). African Journal of Anaesthesia and Intensive Care.

  1. Communities of color? Client-to-client racial concordance in the selection of mental health programs for Caucasians and African Americans.

    Science.gov (United States)

    Koizumi, Naoru; Rothbard, Aileen B; Smith, Tony E; Mayer, Jeremy D

    2011-12-01

    A discrete-choice logit model was applied to study the determinants of mental health provider choice using data from a large urban county in the Northeast US. The study subjects were 9,544 adult Medicaid recipients who received outpatient treatment from the 20 Community Mental Health Center (CMHC) programs in 2001. In addition to a conventional set of variables representing client and provider characteristics, the regression model included several interaction terms to examine whether racial concordance level among patients influences the choice of an outpatient program. The results revealed that racial concordance among the clients seems to be a factor in choosing a program. In particular, Caucasian clients are much more likely to select a program with a higher percentage of Caucasian clients, even though they have to travel further. More generally, our results suggest that program choice may be driven more by the racial composition of the clients served than by spatial proximity to the program.

  2. In vitro fermentation studies for selection and evaluation of Bacillus strains as starter cultures for the production of okpehe, a traditional African fermented condiment.

    Science.gov (United States)

    Oguntoyinbo, Folarin A; Sanni, Abiodun I; Franz, Charles M A P; Holzapfel, Wilhelm H

    2007-01-25

    Selected Bacillus and Enterococcus strains, isolated from traditional okpehe fermentations, were studied for their suitability as starter cultures in laboratory-scale fermentations of Prosopis africana seeds for the production of okpehe, a traditional fermented vegetable product of Nigeria. The strains were selected on the basis of highest proteolytic activity, as determined with the APIZYM (BioMerieux) test. The choice of starter strains was narrowed to Bacillus subtilis strains BFE 5301 and BFE 5372. These were determined as the best starter combination because of rapid growth, high amylolytic and proteolytic activities, high levels of polyglutamic acid production by strain BFE 5372, as well as bacteriocin production by strain BFE 5301. Other mixed culture fermentations did not yield sensorically acceptable products. Although a monoculture fermentation, using only B. subtilis strain BFE 5372, produced okpehe with very good sensory characteristics, the growth of B. cereus could be detected after 48 h fermentation, indicating that this starter did not sufficiently contribute to product safety. Mixed culture fermentation with the combination of bacteriocin-producing starter B. subtilis BFE 5301 and the non-bacteriocin-producing B. subtilis BFE 5372, produced a product with good sensory characteristics, in which growth of B. cereus was delayed. The bacteriocin produced by B. subtilis strain BFE 5301 was identified as subtilisin, using subtilisin-specific primers and PCR amplification of the subtilisin gene. The bacteriocin was heat-stable at 100 degrees C for 10 min and exhibited highest activity at pH values lower or equal to pH 6.0. The bacteriocin was sensitive to the proteolytic enzymes trypsin and alpha-chymotrypsin at concentrations of 10 mg/ml.

  3. Observations on placentome diameters in gestating West African ...

    African Journals Online (AJOL)

    ADEYEYE

    2015-09-09

    com. Abstract. This study investigated the effect of experimental Trypanosoma brucei infection on the placentome diameter (PD) of twenty four gestating West African dwarf does. The does were randomized into 4 equal groups ...

  4. A resistance locus in the American heirloom rice variety Carolina Gold Select is triggered by TAL effectors with diverse predicted targets and is effective against African strains of Xanthomonas oryzae pv. oryzicola.

    Science.gov (United States)

    Triplett, Lindsay R; Cohen, Stephen P; Heffelfinger, Christopher; Schmidt, Clarice L; Huerta, Alejandra I; Tekete, Cheick; Verdier, Valerie; Bogdanove, Adam J; Leach, Jan E

    2016-09-01

    The rice pathogens Xanthomonas oryzae pathovar (pv.) oryzae and pv. oryzicola produce numerous transcription activator-like (TAL) effectors that increase bacterial virulence by activating expression of host susceptibility genes. Rice resistance mechanisms against TAL effectors include polymorphisms that prevent effector binding to susceptibility gene promoters, or that allow effector activation of resistance genes. This study identifies, in the heirloom variety Carolina Gold Select, a third mechanism of rice resistance involving TAL effectors. This resistance manifests through strong suppression of disease development in response to diverse TAL effectors from both X. oryzae pathovars. The resistance can be triggered by an effector with only 3.5 central repeats, is independent of the composition of the repeat variable di-residues that determine TAL effector binding specificity, and is independent of the transcriptional activation domain. We determined that the resistance is conferred by a single dominant locus, designated Xo1, that maps to a 1.09 Mbp fragment on chromosome 4. The Xo1 interval also confers complete resistance to the strains in the African clade of X. oryzae pv. oryzicola, representing the first dominant resistance locus against bacterial leaf streak in rice. The strong phenotypic similarity between the TAL effector-triggered resistance conferred by Xo1 and that conferred by the tomato resistance gene Bs4 suggests that monocots and dicots share an ancient or convergently evolved mechanism to recognize analogous TAL effector epitopes. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  5. 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.

  6. Effectiveness of a selective intervention program targeting personality risk factors for alcohol misuse among young adolescents: results of a cluster randomized controlled trial

    NARCIS (Netherlands)

    Lammers, J.; Goossens, F.; Conrod, P.; Engels, R.; Wiers, R.W.; Kleinjan, M.

    2015-01-01

    Aim: The effectiveness of Preventure was tested on drinking behaviour of young adolescents in secondary education in the Netherlands. Design: A cluster randomized controlled trial was carried out, with participants assigned randomly to a two-session coping skills intervention or a control

  7. Aqueous and Organic Solvent-Extracts of Selected South African Medicinal Plants Possess Antimicrobial Activity against Drug-Resistant Strains of Helicobacter pylori: Inhibitory and Bactericidal Potential

    Directory of Open Access Journals (Sweden)

    Collise Njume

    2011-09-01

    Full Text Available The aim of this study was to identify sources of cheap starting materials for the synthesis of new drugs against Helicobacter pylori. Solvent-extracts of selected medicinal plants; Combretum molle, Sclerocarya birrea, Garcinia kola, Alepidea amatymbica and a single Strychnos species were investigated against 30 clinical strains of H. pylori alongside a reference control strain (NCTC 11638 using standard microbiological techniques. Metronidazole and amoxicillin were included in these experiments as positive control antibiotics. All the plants demonstrated anti-H. pylori activity with zone diameters of inhibition between 0 and 38 mm and 50% minimum inhibitory concentration (MIC50 values ranging from 0.06 to 5.0 mg/mL. MIC50 values for amoxicillin and metronidazole ranged from 0.001 to 0.63 mg/mL and 0.004 to 5.0 mg/mL respectively. The acetone extracts of C. molle and S. birrea exhibited a remarkable bactericidal activity against H. pylori killing more than 50% of the strains within 18 h at 4× MIC and complete elimination of the organisms within 24 h. Their antimicrobial activity was comparable to the control antibiotics. However, the activity of the ethanol extract of G. kola was lower than amoxicillin (P < 0.05 as opposed to metronidazole (P > 0.05. These results demonstrate that S. birrea, C. molle and G. kola may represent good sources of compounds with anti-H. pylori activity.

  8. The antibacterial activity, antioxidant activity and selectivity index of leaf extracts of thirteen South African tree species used in ethnoveterinary medicine to treat helminth infections.

    Science.gov (United States)

    Adamu, Mathew; Naidoo, Vinny; Eloff, Jacobus N

    2014-03-03

    Diseases caused by bacteria remain a major challenge globally and particularly in sub-Saharan Africa. The plants used in this study have been used in South Africa to treat helminth infections in livestock and humans. In a previous study we found a correlation between antifungal and anthelmintic activity in some cases. In this study we examined other potential uses of these thirteen plant species by determining the antibacterial and antioxidant activity of the leaf acetone extracts.The antibacterial activity was determined by using a serial microdilution method against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Enterococcus faecalis. Bioautography was used to determine the number of antibacterial compounds. The antioxidant activity was determined using the ABTS and DPPH methods. Maesa lanceolata and Leucosidea sericea with an MIC of 0.02 mg/ml had excellent antibacterial activity against Enterococcus faecalis and Pseudomonas aeruginosa. There was a poor correlation between antioxidant activity and antibacterial activity with R2 = 0.143. This is because antibacterial activity is mainly related to non-polar compounds and antioxidant activity to polar compounds. Maesa lanceolata extracts had a low cytotoxicity with a selectivity index of 5.2, 2.6, 2.6 and 1.3 for P. aeruginosa, E. faecalis, E. coli and S. aureus respectively. Strychnos mitis extracts had a therapeutic index of 1.1 for E. coli. This study shows that plant extracts of some species used in ethnoveterinary medicine as anthelmintic may also have excellent antibacterial activity.

  9. 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.

  10. Difference in Association of Obesity With Prostate Cancer Risk Between US African American and Non-Hispanic White Men in the Selenium and Vitamin E Cancer Prevention Trial (SELECT).

    Science.gov (United States)

    Barrington, Wendy E; Schenk, Jeannette M; Etzioni, Ruth; Arnold, Kathryn B; Neuhouser, Marian L; Thompson, Ian M; Lucia, M Scott; Kristal, Alan R

    2015-06-01

    African American men have the highest rates of prostate cancer incidence and mortality in the United States. Understanding underlying reasons for this disparity could identify preventive interventions important to African American men. To determine whether the association of obesity with prostate cancer risk differs between African American and non-Hispanic white men and whether obesity modifies the excess risk associated with African American race. Prospective study of 3398 African American and 22,673 non-Hispanic white men who participated in the Selenium and Vitamin E Cancer Prevention Trial (2001-2011) with present analyses completed in 2014. Total, low-grade (Gleason score cancer incidence. With a median (interquartile range) follow-up of 5.6 (1.8) years, there were 270, 148, and 88 cases of total, low-, and high-grade prostate cancers among African American men and a corresponding 1453, 898, and 441 cases in non-Hispanic white men, respectively. Although not associated with risk among non-Hispanic white men, BMI was positively associated with an increase in risk among African American men (BMI, risk associated with African American race increased from 28% (HR, 1.28 [95% CI, 0.91-1.80]) among men with BMI less than 25 to 103% (HR, 2.03 [95% CI, 1.38-2.98]) among African American men with BMI at least 35 (P for trend = .03). Body mass index was inversely associated with low-grade prostate cancer risk within non-Hispanic white men (BMI, risk within African American men (BMI, risk of high-grade prostate cancer in both non-Hispanic white men (BMI, Obesity is more strongly associated with increased prostate cancer risk among African American than non-Hispanic white men and reducing obesity among African American men could reduce the racial disparity in cancer incidence. Additional research is needed to elucidate the mechanisms underlying the differential effects of obesity in African American and non-Hispanic white men.

  11. A Multi-Center, Randomized, Controlled, Pivotal Study to Assess the Safety and Efficacy of a Selective Cytopheretic Device in Patients with Acute Kidney Injury.

    Directory of Open Access Journals (Sweden)

    James A Tumlin

    Full Text Available Acute kidney injury (AKI is a highly morbid condition in critically ill patients that is associated with high mortality. Previous clinical studies have demonstrated the safety and efficacy of the Selective Cytopheretic Device (SCD in the treatment of AKI requiring continuous renal replacement therapy in the intensive care unit (ICU.A randomized, controlled trial of 134 ICU patients with AKI, 69 received continuous renal replacement therapy (CRRT alone and 65 received SCD therapy.No significant difference in 60-day mortality was observed between the treated (27/69; 39% and control patients (21/59; 36%, with six patients lost to follow up in the intention to treat (ITT analysis. Of the 19 SCD subjects (CRRT+SCD and 31 control subjects (CRRT alone who maintained a post-filter ionized calcium (iCa level in the protocol's recommended range (≤ 0.4 mmol/L for greater or equal to 90% of the therapy time, 60-day mortality was 16% (3/19 in the SCD group compared to 41% (11/27 in the CRRT alone group (p = 0.11. Dialysis dependency showed a borderline statistically significant difference between the SCD treated versus control CRRT alone patients maintained for ≥ 90% of the treatment in the protocol's recommended (r iCa target range of ≤ 0.4 mmol/L with values of, 0% (0/16 and 25% (4/16, respectively (P = 0.10. When the riCa treated and control subgroups were compared for a composite index of 60 day mortality and dialysis dependency, the percentage of SCD treated subjects was 16% versus 58% in the control subjects (p<0.01. The incidence of serious adverse events did not differ between the treated (45/69; 65% and control groups (40/65; 63%; p = 0·86.SCD therapy may improve mortality and reduce dialysis dependency in a tightly controlled regional hypocalcaemic environment in the perfusion circuit.ClinicalTrials.gov NCT01400893 http://clinicaltrials.gov/ct2/show/NCT01400893.

  12. A prospective randomized multicenter trial of amnioreduction versus selective fetoscopic laser photocoagulation for the treatment of severe twin–twin transfusion syndrome

    Science.gov (United States)

    Crombleholme, Timothy M.; Shera, David; Lee, Hanmin; Johnson, Mark; D’Alton, Mary; Porter, Flint; Chyu, Jacquelyn; Silver, Richard; Abuhamad, Alfred; Saade, George; Shields, Laurence; Kauffman, David; Stone, Joanne; Albanese, Craig T.; Bahado-Singh, Ray; Ball, Robert H.; Bilaniuk, Larissa; Coleman, Beverly; Farmer, Diana; Feldstein, Vickie; Harrison, Michael R.; Hedrick, Holly; Livingston, Jeffrey; Lorenz, Robert P.; Miller, David A.; Norton, Mary E.; Polzin, William J.; Robinson, Julian N.; Rychik, Jack; Sandberg, Per L.; Seri, Istvan; Simon, Erin; Simpson, Lynn L.; Yedigarova, Larisa; Wilson, R. Douglas; Young, Bruce

    2009-01-01

    Objective To examine the effect of selective fetoscopic laser photocoagulation (SFLP) versus serial amnioreduction (AR) on perinatal mortality in severe twin-twin transfusion syndrome (TTTS). Study Design 5-year multicenter prospective randomized controlled trial. The primary outcome variable was 30-day postnatal survival of donors and recipients. Results There is no statistically significant difference in 30-day postnatal survival between SFLP or AR treatment for donors at 55% (11/20) vs 55% (11/20) (p=1, OR=1, 95%CI=0.242 to 4.14) or recipients at 30% (6/20) vs 45% (9/20) (p=0.51, OR=1.88, 95%CI=0.44 to 8.64). There is no difference in 30-day survival of one or both twins on a per pregnancy basis between AR at 75% (15/20) and SFLP at 65% (13/20) (p=0.73, OR=1.62, 95%CI=0.34 to 8.09). Overall survival (newborns divided by the number of fetuses treated) is not statistically significant for AR at 60% (24/40) vs SFLP 45% (18/40) (p=0.18, OR=2.01, 95%CI=0.76 to 5.44). There is a statistically significant increase in fetal recipient mortality in the SFLP arm at 70% (14/20) versus the AR arm at 35% (7/20) (p=0.25, OR=5.31, 95%CI=1.19 to 27.6). This is offset by increased recipient neonatal mortality of 30% (6/20) in the AR arm. Echocardiographic abnormality in recipient twin Cardiovascular Profile Score is the most significant predictor of recipient mortality (p=0.055, OR=3.025/point) by logistic regression analysis. Conclusions The outcome of the trial does not conclusively determine whether AR or SFLP is a superior treatment modality. TTTS cardiomyopathy appears to be an important factor in recipient survival in TTTS. PMID:17904975

  13. A randomized control trial to evaluate the effect of adjuvant selective laser trabeculoplasty versus medication alone in primary open-angle glaucoma: preliminary results

    Directory of Open Access Journals (Sweden)

    Lee JWY

    2014-09-01

    Full Text Available Jacky WY Lee,1,2 Catherine WS Chan,2 Mandy OM Wong,3 Jonathan CH Chan,3 Qing Li,2 Jimmy SM Lai2 1The Department of Ophthalmology, Caritas Medical Centre, 2The Department of Ophthalmology, The University of Hong Kong, 3The Department of Ophthalmology, Queen Mary Hospital, Hong Kong Background: The objective of this study was to investigate the effects of adjuvant selective laser trabeculoplasty (SLT versus medication alone on intraocular pressure (IOP control, medication use, and quality of life in patients with primary open-angle glaucoma.Methods: This prospective, randomized control study recruited 41 consecutive primary open-angle glaucoma subjects with medically-controlled IOP ≤21 mmHg. The SLT group (n=22 received a single 360-degree SLT treatment. The medication-only group (n=19 continued with their usual treatment regimen. In both groups, medication was titrated to maintain a target IOP defined as a 25% reduction from baseline IOP without medication, or <18 mmHg, whichever was lower. Outcomes, which were measured at baseline and at 6 months, included the Glaucoma Quality of Life-15 (GQL-15 and Comparison of Ophthalmic Medications for Tolerability (COMTOL survey scores, IOP, and the number of antiglaucoma medicines. Results: The baseline IOP was 15.8±2.7 mmHg and 14.5±2.5 mmHg in the SLT and medication-only groups, respectively (P=0.04. Both groups had a comparable number of baseline medication (P=0.2, GQL-15 (P=0.3 and COMTOL scores (P=0.7. At 6 months, the SLT group had a lower IOP (P=0.03 and required fewer medications compared with both baseline (P<0.0001 and with the medication-only group (P=0.02. There was no statistically significant difference in the 6-month GQL-15 or COMTOL score as compared to baseline (P≥0.4 or between the two treatment groups (P≥0.2.Conclusion: A single session of adjuvant SLT provided further reductions in IOP and medication without substantial changes in quality of life or medication tolerability at 6

  14. How to understand, evaluate and influence efficient progress in South Africa’s land reform process: A typology from historical lessons from selected sub-Saharan African countries

    Directory of Open Access Journals (Sweden)

    Nhlanhla C. Mbatha

    2017-12-01

    Full Text Available Background: With reports of widespread failures in South Africa’s land reform programmes, the levels of policy uncertainty in the political rhetoric that influences land reform have been increasing. Since 1994 policy targets to transfer land to black farmers have not been met. Of the 2005 target to transfer about 25 million ha of commercial farmland to black farmers by 2014, less than 5 million ha. have been transferred for commercial use. Some studies report failure rates in resettlement projects of up to 90%. To account for the failures, revisions of policies and amendments to legislations have been proposed within a political environment that is becoming increasingly intolerant to slow progress in land transfers and to resettlement failures. Aim: Against this environment, this paper presents a typology for understanding and evaluating important elements of the land reform project in order to influence progress in the process. Setting: The study adopts a historical review of land reform processes in post-colonial Kenya and Zimbabwe in order to identify potential challenges and key lessons for South Africa. Methods: Hence, using institutional and historical analytical lenses in exploring different narratives, the paper reviews reported failures and successes in land reform policy cases from the selected countries. From an institutional framework, prevalent social institutions and key lessons from Kenya, Zimbabwe and South Africa, a typology for evaluating important elements of the land reform process in South Africa is developed and discussed. Additionally, a review of global data collected on average sizes of farms in different regions of the world is provided as evidence to support propositions of what would constitute efficient farmland size ranges for small to medium commercial farms in South Africa. Results and conclusion: A proposition is made on how to use the typology to guide policy and research interventions to reduce failures

  15. Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial

    National Research Council Canada - National Science Library

    Reales, Jos? M; Mayas, Julia; Ruiz-Marquez, Elo?Sa; Ballesteros, Soledad; Prieto, Antonio; Toril, Pilar

    2017-01-01

    .... Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity, a commercial platform (http://www.lumosity.com...

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

    African Journals Online (AJOL)

    Toshiba

    Indexed African Journals Online: www.ajol.info ensure stability in the political system; and use a collective effort to ... The hope for African integration was rekindled by late Libyan leader. Muammar el-Gaddafi during the ... integrating area (Anadi, 2005) Integration (Olukoshi, 2010), is understood and employed not just or ...

  17. chitwood on African yam bean, Sphenostylis stenocarpa

    African Journals Online (AJOL)

    Yomi

    2012-01-24

    Jan 24, 2012 ... The experiments were laid out in a completely randomized design ... cloning with the aim of imparting pest resistance to plants. (Omitogun, et al. ..... The effects of M. incognita infection on growth parameters of 12 African yam bean accessions, S. stenocarpa, in a screen house experiment. Accession. Health.

  18. Situating globality: African agency in the appropriation of global culture

    OpenAIRE

    Binsbergen, van, W.M.J.; Dijk, van, K.R.A.; Gewald, J.B.

    2004-01-01

    The papers in this volume were earlier presented at the conference 'Globalization and new questions of ownership', which was held in Leiden, The Netherlands, from 26-27 April 2002. The volume challenges the dominant view that globalization is a primary threat to African societies. Instead, it emphasizes African agency in situating globality, that is, in selectively and creatively appropriating elements of the emerging global culture. Contributions: Situating globality: African agency in the a...

  19. African Journals Online (AJOL)

    African Journals Online (AJOL)

    reviewed, African-published scholarly journals. ... Featured Country: Nigeria, Featured Journal: West African Journal of Industrial and Academic Research. Most recent issues on AJOL: Vol 6, No 1 (2015). Nigeria Journal of Pure and Applied Physics.

  20. African Studies Monographs

    African Journals Online (AJOL)

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    African Journals Online (AJOL)

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