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Item A first syntaxonomic description of the vegetation of the Karstveld in Namibia.(Vegetation Classification and Survey/Pensoft Publishers, 2023-10-24) Strohbach, Ben J.; Strohbach, Marianne M.Aims: The Karstveld in Namibia has been recognized as an area of high plant diversity. However, this area is also recog nised as a hotspot of various forms of degradation including bush encroachment. Minimal baseline data on the compo sition and diversity of vegetation in this area is available, therefore this paper is a first attempt to rectify this data defi ciency. Study area: The Karstveld in Namibia is formed around the Otavi Mountain Range in northern Central Namibia, consisting of strongly karstified carbonate bedrock, rising up to 2000 m a.s.l. The Karstveld includes the Ovambo Basin plains with shallow calcrete soils north of the range, up to the Omuramba Ovambo. Because of orographic effects, the area receives some of the highest rainfall in Namibia, with up to 600 mm per year. Methods: A set of 889 relevés with 868 species was selected from the GVID ID AF-NA-001 database. A partial data set, using trees, shrubs, dwarf shrubs and grasses only, was used for the classification with modified TWINSPAN. The initial result yielded four main groups, according to which the data was split and further classified. Several vegetation types observed during field surveys were not reflected in the classification results; these were refined using Cocktail with known characteristic species. Results: The four main units represented wetlands and grasslands with six associations, a Thornbush savanna – Karstveld tran sition zone with four associations, Kalahari vegetation with four associations and the Karstveld proper with eight asso ciations. The latter are grouped together as the Terminalietea prunioides, with two orders and three alliances recognised under them. We describe 16 associations according to the ICPN. Conclusions: Although the associations presented in this paper are clearly defined, there exists a high degree of diversity within these. The Karstveld is also extraordinary species rich within the context of the arid to semi-arid Namibian environment. Taxonomic reference: Klaassen and Kwembeya (2013) for vascular plants, with the exception of the genus Acacia s.l. (Fabaceae), for which Kyalangalilwa et al. (2013) was followed. Abbreviations: ga = annual grass; gp = perennial grass; GPS = Global Positioning System, referring to a hand-held ground receiver; hl = herb layer, containing all hemicryptophytes, therophytes and geophytes, but excluding grasses (Poaceae); ICPN = International Code of Phytosociological Nomenclature (Theurillat et al. 2021); MAP = mean annual precipitation; NMS = nonmetric multidimensional scaling (Kruskal 1964); RDL = Red Data List (IUCN Species Survival Commission 2001); s1 = tall shrubs, i.e. multi-stemmed phanerophytes between 1 and 5 m; s2 = short shrubs, i.e. cha maephytes or ‘dwarf shrubs’ below 1 m; SOTER = Global and National Soils and Terrain Digital Database (FAO 1993); t1 = tall trees, > 10 m; t2 = short trees, between 5 and 10 m; t3 = low trees, i.e. single-stemmed phanerophytes between 2 and 5 m; TWINSPAN = Two Way Indicator Species Analysis (Roleček et al. 2009); WGS84 = World Geodetic System, 1984 ensemblItem Prevalence of human immunodeficiency virus, syphilis, hepatitis B and C in blood donations in Namibia.(BMC Public Health, 2014) Mavenyengwa, Rooyen T.; Mukesi, Munyaradzi; Chipare, Israel; Shoombe, EsraBackground: Transfusion Transmissible Infections (TTIs) such as Human Immunodeficiency Virus (HIV), syphilis, hepatitis B virus (HBV) and hepatitis C virus (HCV) are infections which are common in some communities in Southern Africa. It is important to screen blood donations for these infections. Methods: This is a retrospective study which involved reviewing of previous blood donation records for the year 2012 in Namibia. The records were analyzed to determine the prevalence of HIV, syphilis, Hepatitis B and C among blood donations with regard to gender, age and geographical region of the donors. Results: The findings indicated a significantly low prevalence of HIV, syphilis, HBsAg and anti-Hepatitis C among the blood donations. A low infection rate of 1.3% by any of the four tested TTIs was found among the blood donations given by the donor population in Namibia in 2012. Conclusion: The blood donations given by the donor population in Namibia has a low infection rate with the HIV, syphilis, HBsAg and anti-HCV. A strict screening regime must continue to be used as the infections are still present albeit in small numbers.Item Trends in biomedical research in Namibia: 1995-2009.(NUST, 2012) Noden, Bruce H.Research publications are often used as proxies for the scientific progress and development of a particular country. Country-specific bibliometric studies reflect national strategies to build capacity in tertiary education, research, and health services. In Namibia, no study to date has analyzed trends at the country level. The aim of this study was to evaluate the biomedical publication patterns in Namibia between 1995 and 2009. Using the keyword ‘Namibia’ in PubMed and ISI Web of Knowledge, resulting papers were hand searched for information on subject areas, types of studies undertaken, first authorship patterns, and institutions involved in biomedically-focused publications. This study identified 450 publications between 1995 and 2009. Only 129 (28.6%) involved Namibian authors. Just over half (58%) of the studies were carried out in Namibia but varied dramatically by subject area. 52% of Namibian-authored papers were Namibian first-authored with a decreasing trend since 2004. Only 7.5% (34) of the publications involved authors from Namibian universities. Namibia has a strong potential to develop in biomedical research but there is a need for tertiary institutions to modify current policies, continue to diversify sub- areas and become equipped to build capacity with local and international collaborators.Item Novel aspects of the Z and R3 antigens of streptococcus agalactiae revealed by immunological testing.(ASM: American Society for Microbiology, 2013) Maeland, Johan A.; Radtke, Andreas; Lyng, Randi V.; Mavenyengwa, Rooyen T.Group B streptococci (GBS) are important human and bovine pathogens which can be classified by a variety of phenotype- and gene-based techniques. The capsular polysaccharide and strain-variable, surface-anchored proteins are particularly important phenotypic markers. In an earlier study, a previously unrecognized protein antigen called Z was described. It was expressed by 27.2% of GBS strains from Zimbabwe, usually in combination with R3 protein expression. In this study, a putative Z-specific antiserum actually contained antibodies against two different antigens named Z1 and Z2; Z1 was>250 kDa in molecular mass. Z1, Z2, and R3 generated multiple stained bands on Western blots and showed similar chromatographic characteristics with respect to molecular mass, aggregate formation, and charge. Of 28 reference and prototype GBS strains examined, 8/28 (28.5%) isolates expressed one, two, or all three of the Z1, Z2, and R3 antigens; 4/28 expressed all three antigens; 2/28 expressed Z2 and R3; 1/28 expressed Z1 only; and 1/28 expressed R3 only. Twenty (71.5%) of the 28 isolates expressed none of the three antigens. Expression of one or more of these antigens was shown by isolates of the capsular polysaccharide types Ia, Ib, V, and IX and NT strains and occurred in combination with expression of various other strain-variable and surface-localized protein antigens. When used as serosubtype markers, Z1, Z2, and R3 affected existing GBS serotype designations for some of the isolates. For instance, the R3 reference strain Prague 10/84 (ATCC 49447) changed serotype markers from V/R3 to V/R3, Z1, and Z2. Other isolates may change correspondingly, implying consequences for GBS serotyping and research.Item Biomedically-focused research productivity by Namibian authors and institutions 1995-2010.(NUST, 2011) Noden, Bruce H.Publications are the result of individual scientists or ‘webs’ of collaborators who present their scientific observations and share them with the scientific community. A study of authors and institutions who have published provides way to assess a country’s research environment. Using PubMed and ISI Web of Science, this study identified Namibian authors and institutions which published biomedically-focused studies between 1995 and 2010. Results consisted of 150 different biomedically-oriented publications by a total of 190 different authors from 44 different institutions. 89% of the articles by Namibian authors were the results of collaboration, either foreign or Namibian-based. 47% of the papers were 1st authored and 11% were single authored by Namibian-based authors. The majority of Namibian authors (72%) only produced one article while 28% produced 2 or more papers. Further analysis indicated that there has been a negative trend in the number of publications since 1998 which contrasts with the increasing number of institutions which have published at least one article during that period. In total, these results indicate that the biomedical science environment in Namibia has potential to develop and expand. However, it needs support from a national biomedical research strategy based on Namibian-informed research priorities, investment in potential authors and institutions and empowered tertiary institutions taking the lead to equip and build capacity in local collaborators in order to reach its true potential.Item Age-specific mortality patterns in Central Mozambique during and after the end of the Civil War.(BioMed Central, 2011) Noden, Bruce H.; Pearson, John R.C.; Gomes, AurelioBackground: In recent years, vigorous debate has developed concerning how conflicts contribute to the spread of infectious diseases, and in particular, the role of post-conflict situations in the epidemiology of HIV/AIDS. This study details the age-specific mortality patterns among the population in the central provincial capital of Beira, Mozambique, during and after the Mozambican civil war which ended in 1992. Methods: Data was collected from the death register at Beira’s Central Hospital between 1985 and 2003 and descriptively analyzed. Results: The data show two distinct periods: before and after the peace agreements in 1992. Before 1992 (during the civil war), the main impact of mortality was on children below 5 years of age, including still births, accounting for 58% of all deaths. After the war ended in 1992, the pattern shifted dramatically and rapidly to the 15-49 year old age group which accounted for 49% of all deaths by 2003. Conclusions: As under-5 mortality rates were decreasing at the end of the conflict, rates for 24-49 year old adults began to dramatically increase due to AIDS. This study demonstrates that strategies can be implemented during conflicts to decrease mortality rates in one vulnerable population but post-conflict dynamics can bring together other factors which contribute to the rapid spread of other infectious diseases in other vulnerable populations.Item Influence of religious affiliation and education on HIV knowledge and HIV-related sexual behaviors among youth in rural central Mozambique.(Taylor & Francis, 2010) Noden, Bruce H.; Gomes, Aurelio; Ferreira, AldinaThe interactions between religious affiliation, education, HIV knowledge, and HIV-related sexual behaviors among African church youth are poorly understood. In this socio-demographic study, 522 unmarried youth 12-28 years old in rural central Mozambique were surveyed with a structured questionnaire. Using binary logistic regression analysis, we used religious affiliation and education to measure influence on (1) HIV transmission and prevention knowledge and attitudes and (2) HIV-related sexual behaviors among youth. Religiously affiliated males were more likely than non-religious males to know when a condom should be used, respond correctly to HIV transmission questions and respond with less stigma to HIV-related scenarios. Increased levels of education among males corresponded significantly to increased knowledge of condom usage and HIV prevention strategies and less likelihood to respond with stigma. Only education levels influenced young female responses. Religious affiliation and education had minimal effects on sexual activity, condom usage, and multiple partnerships. African Independent Church/Zionist males were 1.6 more likely to be sexually inexperienced than nonreligious males but were also significantly less likely to use condoms (0.23, p=0.024). Non-religious youth were most likely to have visited sex workers and did not use condoms. These results suggest that religious affiliation, possibly as the result of educational opportunities afforded by religious-affiliated schools, is contributing to increased HIV transmission and prevention knowledge among youth in rural Central Mozambique but not influencing HIV-related sexual behavior. The need exists to strengthen the capacity of religious congregations to teach about HIV/AIDS and target non-religious youth with HIV transmission and prevention information.Item AIDS-related knowledge and sexual behaviour among married and previously married persons in rural Mozambique.(2009) Noden, Bruce H.; Gomes, Aurelio; Ferreira, AldinaHIV prevalence in central Mozambique is the highest in the country with high urban rates impacting on the rural areas. To identify potential factors influencing the spread of HIV in three sparsely populated districts in southern Sofala province, 847 married and previously married persons were surveyed for their knowledge, practices and beliefs regarding HIV/AIDS and STIs. 21.9% and 6.5% of males and females, respectively, were engaged in casual sexual partnerships in the past year. Being male, married, educated, and having genital discharge and ulcers in the last year were significantly associated with risky sexual activity. Risky behaviour was significantly associated with being Catholic or Protestant when compared with those from Zionist churches. Knowledge of ABC prevention strategies and condom usage was significantly associated with being male, married, having an STI in the past year, and being educated, particularly at the secondary level (Grade 8+). Attitudes and behaviour were influenced by cultural and religious involvement, as well as sex and marital status. It is imperative that prevention strategies take into account the cultural, economic and religious conditions present in rural African settings to create HIV prevention programmes that are culturally relevant and acceptable to the participants.