24 research outputs found
Erratum to: Risky Sex and HIV Acquisition Among HIV Serodiscordant Couples in Zambia, 2002–2012: What Does Alcohol Have To Do With It?
No full textThe article Risky Sex and HIV Acquisition Among HIV Serodiscordant Couples in Zambia, 2002–2012: What Does Alcohol Have To Do With It?, written by Dvora Joseph Davey, William Kilembe, Kristin M. Wall, Naw Htee Khu, Ilene Brill, Bellington Vwalika, Elwyn Chomba, Joseph Mulenga, Amanda Tichacek, Marjan Javanbakht, W. Scott Comulada, Susan Allen, Pamina M. Gorbach, was originally published Online First without open access. After publication in volume 21, issue 7, pages 1892–1903, the author decided to opt for Open Choice and to make the article an open access publication. Therefore, the copyright of the article has been changed to © The Author(s) [Year] and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, duplication, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made
Design and Synthesis of Metallic and Metal Oxide Nanomaterials for Environmental Catalysis
No full textMetallic and metal oxide nanomaterials are increasingly being used for air pollution control, remediation, and development of environmentally sustainable technologies. This research work focused on development of facile methods for synthesis of metallic and mixed-metal oxides for environmental catalysis. The dissertation consists of three sections. ^ The first part describes the preparation of bimetallic copper manganese oxides at ambient temperature using a novel redox method and their use for removal of carbon monoxide and volatile organic pollutants from dilute gas streams. The synthesized copper manganese oxides had high intrinsic catalytic activity attributed to a combination of factors including compositional homogeneity, poor crystallinity, and high surface area. Homogeneous incorporation of copper into the amorphous manganese oxide matrix enhanced the redox properties of the resultant bimetallic oxides. ^ The second part demonstrates bulk biosynthesis of colloidal iron and silver nanoparticles using a rapid, single step, and completely green biosynthetic method employing aqueous sorghum extracts as both the reducing and capping agent. The synthesized iron nanoparticles effectively degraded bromothymol blue, a model organic contaminant. The synthesized metallic silver nanoparticles were of high purity, highly crystalline, and are spherical with an average diameter of about 10 nm. The synthesized silver nanoparticles are therefore potentially useful for biological applications. ^ The third part describes the synthesis of sulfated metal and mixed metal oxides and their use for selective dehydration of various biomass resources to levuninate esters. These solid acid catalysts offer several advantages over mineral acids typically employed for biomass conversion including high selectivity, easy separation from products, and efficient recyclability.
Notarius planiceps
No full text<p> <i>Notarius planiceps</i> (Steindachner 1876). Thick-Lip Sea-Catfish; Cuminate, Cominata Chomba, Bagre Chombo</p> <p> <b>Vouchers:</b> Not available. <b>Distribution:</b> Eastern Pacific Ocean; from southern Baja California, Mexico, to Colombia; entering estuaries and littoral lagoons and ascending river courses; <b>(Nicaragua)</b> PN (Pacific); 0–7 masl; Per, Dia, Amp. <b>Occurrence and conservation status:</b> Nat; LC (2010), population trend unknown. <b>Literature:</b> Villa (1982: 116, as <i>Netuma planiceps</i> —misspelled and synonym; detailed description, including illustrations and an identification key, and information on distribution and ecology) and Robertson & Allen (2015: 571; detailed description, including illustrations, and information on distribution, with a map, and ecology).</p>Published as part of <i>Angulo, Arturo, Betts, Joel T., González-Alemán, Néstor J., Castañeda, Edgar, Berghe, Eric Van Den, Elías, Diego J., Mcmahan, Caleb D. & Matamoros, Wilfredo A., 2023, Continental fishes of Nicaragua: diversity, distribution and conservation status; with an annotated and illustrated checklist of species and an identification guide to families, pp. 1-89 in Zootaxa 5376 (1)</i> on page 30, DOI: 10.11646/zootaxa.5376.1.1, <a href="http://zenodo.org/record/10208788">http://zenodo.org/record/10208788</a>
A review of coupled hydrologic-hydraulic models for floodplain assessments in Africa: Opportunities and challenges for floodplain wetland management
No full textFloodplain wetlands are a fundamental part of the African continent’s ecosystem and serve as habitat for fish and wildlife species, biodiversity, and micro-organisms that support life. It is generally recognised that wetlands are and remain fragile ecosystems that should be subject to sustainable conservation and management through the use of sustainable tools. In this paper, we propose a synthesis of the state of art concerning coupled hydrologic and hydraulic models for floodplains assessments in Africa. Case studies reviewed in this paper have pointed out the potential of applying coupled hydrologic and hydraulic models and the opportunities present to be used in Africa especially for data scarce and large basin for floodplain assessments through the use of available open access models, coupling frameworks and remotely sensed datasets. To our knowledge this is the first case study review of this kind on this topic. A Hydrological model coupled with Hydraulic Model of the floodplain provides improvements in floodplain model simulations and hence better information for floodplain management. Consequently, this would lead to improved decision-making and planning of adaption and mitigation measures for sound floodplain wetland management plans and programmes especially with the advent of climate change and variability.Water Resource
Didacticism in the prose - poetry and Narrative fiction of Simon Mwansa Kapwepwe
No full textTowards the end of 1948. the Northern Rhodesia and Nyasaland Joint Pub 1icat ions Bureau which had replaced the African Literature Committee spelt out the production of literature in the indigenous languages as one of its major goals.
Accord ins to John Mwanakatwe (1989). 40 percent of the manuscripts sent to the bureau in 1959 were in Bemba, with a sizeable proportion being works of fiction. What is anomalous, however, is that in spite of such an early start, literature in the indigenous languages continues to be viewed as the 4 terra incognita of literary scholarship. The position is all the more bewildering when one considers the phenomenal development that Zambia has attained in the field of higher education since independence. There is an urgent need for its evaluation and interpretation because indigenous literature - the repository of those values its nationals wish to be embodied in their tradition has rich and unique qualities that add depth and meaning to the nation and its people.
The concern of this dissertation is the style of "didacticism" in the prose - poetry and narrative fiction of Simon Mwansa Kapwepwe - one of the most prolific authors in Bemba literature. This i . of special significance because didactic literature plays a crucial role in the development process of any nation.
The study consists of three chapters. Chapter one i .s introductory and it gives the background and statement of the problem. It indicates the scope, objectives and purpose of the research. It gives a review of related literature and outlines the research procedure used to undertake the study. Chapter two, forms the "core" of the study. In it, we start by giving a general survey of "didacticism" in written Bemba literature as a basis for the analysis of Kapwepwe's works. In doing this, we want to show that other-writers apart from Kapwepwe have used this formal framework as an inspiration for their fictional writing. Following this background we discuss didacticism in the prose-poetry and narrative fiction of Kapwepwe, respectively.
In Utunyonga ndimi (Tongue-twisters), we seek to demonstrate that the importance of this little book does not just lie in its elocutionary purpose, but also in the didactic implication of its content. Our concern in Afrika Kuti Twabelela Uluse Lclo Tekuti TuJabe (Africa we can Forgive but we cannot Forget) is a discussion of the significance of the writer's portrayal of the phases of Africa's history -- past, present and future. Especially, we try to bring out in each phase experiences that have an "instructional" value for society.
Our concern in Shalapo Canicandala (Good-bye Canicandala) is the author's treatment of the Zambian culture and its dese¬cration by European colonialism. Kapwepwe devotes, the first half of this book to an expose of Bemba customs and traditional lore through the question - and - answer format in which the young protagonist Chanda, puts a series of questions, to Canicandala , a wise old man and repository of Bemba culture. This is to prepare him for the shock, when in the second half of the book, he finds himself in an urban setting where the cultural mores of his people are devalued and desecrated. In I'buntungwa mu Jambojambo (Freedom in Jambo jambo) , we trace the struggle for freedom and attempt to analyse its implications for Zambia as depicted by the author-.
Chapter three is the conclusion and it evaluates Kapwepwe's stature as a literary artist in indigenous Literature
Integrated Hydrologic-Hydrodynamic Inundation Modeling in a Groundwater Dependent Tropical Floodplain
No full textThe rapid development of free and open-access hydrological models and coupling framework tools continues to present more opportunities for coupled model development for improved assessment of floodplain hydrology. In this study, we set up an Upper Zambezi hydrological model and a fully spatially hydrological-hydrodynamic coupled model for the Barotse Floodplain using GLOFRIM (GLObally applicable computational FRamework for Integrated hydrological– hydrodynamic Modelling). The hydrological and hydrodynamic models used are WFLOW and LISFLOOD-FP, respectively. The simulated flows generated by the wflow model for the upstream gauge stations before the Barotse Floodplain were quite similar and closely matched the observed flow as indicated by the evaluation statistics; Chavuma, nse = 0.738; kge = 0.738; pbias = 2.561 and RSR = 0.511; Watopa, nse = 0.684; kge = 0.816; pbias = 10.577 and RSR = 0.557; and Lukulu, nse = 0.736; kge = 0.795; pbias = 10.437 and RSR = 0.509. However, even though the wflow hydrological model was able to simulate the upstream hydrology very well, the results at the floodplain outlet gauge stations did not quite match the observed monthly flows at Senanga gauge station as indicated by the evaluation statistics: nse = 0.132; kge = 0.509; pbias = 37.740 and RSR = 0.9233. This is mainly because the representation of both floodplain channel hydrodynamics and vertical hydrological processes is necessary to correctly capture floodplain dynamics. Thus, the need for an approach that saves as a basis for developing fully spatially distributed coupled hydrodynamic and hydraulic models’ assessments for groundwater dependent tropical floodplains such as the Barotse floodplain, in closing the gap between hydrology and hydrodynamics in floodplain assessments. A fully coupled model has the potential to be used in implementing adaptive wetland management strategies for water resources allocation, environmental flow (eflows), flood control, land use and climate change impact assessments.Water Resource
Assessment of Heavy Metal Pollution in Water and Sediment of River Thiba, Kirinyaga County, Kenya
No full textTrace elements find their way into humans through ingestion, direct absorption or inhalation. All trace metals are toxic to animals and plants when present in excess amounts. The harmful effects of trace heavy metals in mammals may manifest as growth retardation, decrease in longevity, changes in reproductive cycles, chronic diseases and tumour formation. River Thiba catchment is Mt. Kenya forest and then flows through rocks, soil, farmlands, residential areas and town centres. Due to geological factors and human activities, trace heavy metals may be getting in river Thiba and since the water is used for domestic purposes and irrigation, it was necessary to determine the heavy metal concentration in the river. Sediment and water samples were collected along river Thiba during rainy and dry seasons. The samples were digested then concentrations of eight heavy metals determined using ICP-MS. The mean amounts of Cd, Cr, Ni, Pb, Zn, As, Mn and Se in sediment were 0.0908, 39.8969, 85.1085, 10.3918, 42.5555, 2.3679, 1678.3876 and 5.4907 mg/kg respectively during rainy season and 0.0628, 42.6319, 396.4692, 3.2669, 58.7585, 2.8139, 1766.4009 and 6.1059 mg/kg respectively during dry season. The mean concentration of the same metals in water was 0.0002, 0.0916, 1.0066, 0.0434, BDL, 0.0025, 1.8484 and 0.0038 ppm respectively during wet season and BDL, BDL, BDL, 0.0068, BDL, 0.00002, 0.0070 and BDL ppm respectively during dry season. The mean amount of Cr, Ni and Mn in sediment were found to be above WHO and US EPA permissible limits during both seasons. During rainy season, the mean concentration of Cr, Ni, Pb and Mn in water were above WHO and KEBS/WASREB permissible limits but the concentrations of Cd, Zn, As and Se were below the limits. However, during dry season, all the eight heavy metal concentrations in water were below WHO, KEBS/WASREB permissible limits. As far as the eight heavy metals are concerned, water from river Thiba may not be potable during rainy season but is potable during dry season. However, further investigations should be carried out to determine other water parameters
Int J Epidemiol
No full textBackgroundStudies have demonstrated the role of ulcerative and non-ulcerative sexually transmitted infections (STI) in HIV transmission/acquisition risk; less is understood about the role of non-specific inflammatory genital abnormalities.MethodsHIV-discordant heterosexual Zambian couples were enrolled into longitudinal follow-up (1994\u20132012). Multivariable models estimated the effect of genital ulcers and inflammation in both partners on time-to-HIV transmission within the couple. Population-attributable fractions (PAFs) were calculated.ResultsA total of 207 linked infections in women occurred over 2756 couple-years (7.5/100 CY) and 171 in men over 3216 CY (5.3/100 CY). Incident HIV among women was associated with a woman\u2019s non-STI genital inflammation (adjusted hazard ratio (aHR) = 1.55; PAF = 8%), bilateral inguinal adenopathy (BIA; aHR = 2.33; PAF = 8%), genital ulceration (aHR = 2.08; PAF = 7%) and the man\u2019s STI genital inflammation (aHR = 3.33; PAF = 5%), BIA (aHR = 3.35; PAF = 33%) and genital ulceration (aHR = 1.49; PAF = 9%). Infection among men was associated with a man\u2019s BIA (aHR = 4.11; PAF = 22%) and genital ulceration (aHR = 3.44; PAF = 15%) as well as with the woman\u2019s non-STI genital inflammation (aHR = 1.92; PAF = 13%) and BIA (aHR = 2.76; PAF = 14%). In HIV-M+F- couples, the man being uncircumcised. with foreskin smegma. was associated with the woman\u2019s seroconversion (aHR = 3.16) relative to being circumcised. In F+M- couples, uncircumcised men with BIA had an increased hazard of seroconversion (aHR = 13.03 with smegma and 4.95 without) relative to being circumcised. Self-reporting of symptoms was low for ulcerative and non-ulcerative STIs.ConclusionsOur findings confirm the role of STIs and highlight the contribution of non-specific genital inflammation to both male-to-female and female-to-male HIV transmission/acquisition risk. Studies are needed to characterize pathogenesis of non-specific inflammation including inguinal adenopathy. A better understanding of genital practices could inform interventions.20172017-04-11T00:00:00ZP30 AI050409/AI/NIAID NIH HHS/United StatesR01 AI040951/AI/NIAID NIH HHS/United StatesR01 HD040125/HD/NICHD NIH HHS/United StatesR01 AI051231/AI/NIAID NIH HHS/United StatesR01 AI023980/AI/NIAID NIH HHS/United StatesR37 AI051231/AI/NIAID NIH HHS/United StatesR01 AI064060/AI/NIAID NIH HHS/United StatesD43 TW001042/TW/FIC NIH HHS/United StatesR01 MH066767/MH/NIMH NIH HHS/United StatesU2G PS000758/PS/NCHHSTP CDC HHS/United States28402442PMC583762
Stakeholder-driven transformative adaptation is needed for climate-smart nutrition security in sub-Saharan Africa - author correction
No full textImproving nutrition security in sub-Saharan Africa under increasing climate risks and population growth requires a strong and contextualized evidence base. Yet, to date, few studies have assessed climate-smart agriculture and
nutrition security simultaneously. Here we use an integrated assessment framework (iFEED) to explore stakeholder-driven scenarios of food system transformation towards climate-smart nutrition security in Malawi, South Africa, Tanzania and Zambia. iFEED translates climate–food–emissions
modelling into policy-relevant information using model output implication statements. Results show that diversifying agricultural production towards more micronutrient-rich foods is necessary to achieve an adequate population-level nutrient supply by mid-century. Agricultural areas must expand unless unprecedented rapid yield improvements are achieved. While these transformations are challenging to accomplish and often
associated with increased greenhouse gas emissions, the alternative for a nutrition-secure future is to rely increasingly on imports, which would outsource emissions and be economically and politically challenging given the large import increases required
Factors influencing male involvement in prevention of mother-to-child transmission services in Khayelitsha, Cape Town, South Africa
No full textThis study sought to explore the role of men in the prevention of mother-to-child transmission services in Khayelitsha, South Africa. Two focus group discussions were held with 25 men of unknown status and one focus group discussion held with 12 HIV-positive women in the community. In-depth interviews were also conducted with four HIV-positive couples and five service providers purposely sampled from the community and a health facility, respectively
