Investigation of gene action for resistance to early leaf spot of groundnut

Groundnut (Arachishypogaea L.) is an important global oilseed crop and a major source of protein and vitamins in many rural areas of Africa. In Zambia, the production of groundnut is limited by several factors, among which Early Leaf Spot (ELS) caused by Cercosporaarachidicola Hori, is a major destructive disease. Development of resistant varieties to ELS remains the most viable disease management strategy. The objective of this study was to investigate the type of gene action conditioning resistance to C. arachidicolain order to generate information for breeding of ELS resistant groundnut varieties in Zambia. The field work was conducted at Chitedze Research Station in Malawi which is a known hot spot for groundnut foliar diseases. A recombinant inbred line (RIL) population developed from a biparental cross (Robut 33-1, susceptible and ICGV-SM 95714, resistant) and consisting of 110 F8 RILs was used in the study. Data for analysis was generated by phenotyping of the RIL population and this was conducted during the 2013/14 season under field conditions supplemented by irrigation. To ensure that there was disease infection in the experimental field, diseased debris was used as primary inoculums. The nature of gene action was established by generating a distribution curve while the Chi-square test was used to confirm the generation level of the population. These were done using the area under disease progress curves (AUDPCs) and the results suggested additive gene action. The study thus concluded that the gene action conditioning resistance to ELS was additive and breeding schemes such as pedigree and single seed decent can be used in breeding for resistance to Cercosporaarachidicola

Computable General Equilibrium Modeling for Regional Analysis

Partial equilibrium analysis illustrates results for one market at a time. However, there often exist market interactions and thus market feedbacks. Pricing outcomes in one market usually have effects in other markets, and these effects, in turn, create ripples throughout the economy, perhaps even to the extent of affecting the price-quantity equilibrium in the original market. To represent this complex set of economic relationships, it is necessary to go beyond partial equilibrium analysis and construct a model that permits viewing many markets simultaneously. This Web Book provides an introduction to and overview of the general equilibrium modeling framework in the context of regional analysis.https://researchrepository.wvu.edu/rri-web-book/1023/thumbnail.jp

The geochronological framework of the Irumide Belt: A prolonged crustal history along the margin of the Bangweulu Craton.

Ion microprobe U-Th-Pb analyses of zircon from 40 granitoid rocks collected from the late Mesoproterozoic Irumide Belt in Central Southern Africa, along the southern margin of the Archean to Paleoproterozoic Bangweulu Block, provide a comprehensive set of age data for this complex orogen. The data indicate that the Irumide Belt is constructed on a basement of principally Paleoproterozoic (ca. 2.05–1.93 Ga) age with a subordinate Neoarchean (ca. 2.73 Ga) component, which is overlain by a platformal quartzite-pelite succession known as the Muva Supergroup. Previously published U-Pb detrital zircon data for the Paleoproterozoic Muva Supergroup, which show age populations that match all of the pre-1.9 Ga basement components identified within the Irumide Belt, suggest that the pre-Muva basement was assembled as a coherent block by ~1.8 Ga, which we refer to as the Bangweulu Craton. The southern margin of the Bangweulu Craton was then intruded by a previously unrecognized suite of biotite-bearing granitoid rocks between 1.66 and 1.55 Ga, not recorded elsewhere in the region, and was later the site of emplacement of voluminous granitoid magmatism during the Irumide Orogeny at between 1.05 and 1.00 Ga. Hf isotopic data from zircon in these suites indicate variable influence from cryptic Archean rocks in the lower crustal melting zone of the Bangweulu Block. U-Pb analyses of inherited zircon cores in magmatic zircon in these granitoid rocks, directly confirm the presence of this reworked cryptic Archean basement of the Bangweulu Craton.The age data confirm previously proposed tectonic models for the Mesoproterozoic evolution of central Africa, refuting the presence of a continent-spanning Grenvillian-aged Orogen, including the Kibaran Belt, Irumide Belt and Choma-Kalomo Block of central Africa and connecting with Mesoproterozoic terranes further south along the margins of the Kalahari Craton. The data clearly show that the Proterozoic tectonic evolution of the Bangweulu Craton, which became attached to the southern margin of the larger Congo Craton during the Mesoproterozoic, involved a series of distinct convergent orogenic episodes affecting and reworking its southern (passive) margin. The mismatch in timing of Mesoproterozoic orogenic activity along the Bangweulu Craton, compared to that on the margins of the Kalahari, is compatible with the notion that these continental fragments were not juxtaposed along these Mesoproterozoic belts and in their present-day relative positions at the time. Whether either of these central and southern African cratons did form part of Rodinia, however, remains a matter for debate

Deciphering cultural differences between local and foreign contracting firms using Hofstede’s national culture model in the construction industry

Most construction works in the Zambian construction industry are executed by foreign contractors who are eligible to tender for large-scale construction projects. These works amount to 85% of the national contract value. Foreign contractors are seen as better performers in project deliverables of time, cost and schedule compared to local contractors. This research investigated the magnitude to which national culture impacts contractor performance in the Zambian construction industry. A comparison of culture and performance was made between foreign and local firms in the two top construction categories, using Hofstede’s national culture framework to determine performance improvements of local contractors. A total 112 questionnaires were collected and SPSS was used to analyse the data descriptive statistics and inferential statistics. Findings revealed that foreign contractors manage uncertainty avoidance in a more superior manner compared to local contractors. The clients rated foreign contractors as better performers apart from health and safety. The study established that Local contractors must improve their performance if they are to compete favourably with the foreign contractors' success record

Improving primary care antimicrobial stewardship by implementing a peer audit and feedback intervention in Cape Town community healthcare centres

Background. The increasing prevalence of antibiotic resistance is a major threat to public health. Primary care, where 80% of antibiotics are consumed, is a pivotal setting to direct antimicrobial stewardship (AMS) efforts. However, the ideal model to improve antibiotic prescribing in primary care in low-resource settings is not known.Objective. To implement a multidisciplinary audit and feedback AMS intervention with the aim to improve appropriate antibiotic prescribing at primary care level.Methods. The intervention was implemented and monitored in 10 primary care centres of the Cape Town metropole between July 2017 and June 2019. The primary and secondary outcome measures were monthly adherence to a bundle of antibiotic quality process measures and monthly antibiotic consumption, respectively. Multidisciplinary audit and feedback meetings were initiated and integrated into facility clinical meetings. Two Excel tools were utilised to automatically calculate facility audit scores and consumption. Once a month, 10 antibiotic prescriptions were randomly selected for a peer review audit by the team. The prescriptions were audited for adherence to a bundle of seven antibiotic process measures using the standard treatment guidelines (STG) and Essential Medicines List (EML) as standard. Concurrently, primary care pharmacists monitored monthly antibiotic consumption by calculating defined daily doses (DDDs) per 100 prescriptions dispensed. Adherence and consumption feedback were regularly provided to the facilities. Learning collaboratives involving representative multidisciplinary teams were held twice-yearly. Pre-, baseline and post-intervention periods were defined as 6 months before, first 6 months and last 6 months of the study, respectively.Results. The mean overall adherence increased from 19% (baseline) to 47% (post intervention) (p<0.001). Of the 2 077 prescriptions analysed, 33.7% had an antibiotic prescribed inappropriately. No diagnosis had been captured in patient notes, and the antibiotic chosen was not according to the STG and EML in 30.1% and 31.7% of cases, respectively. Seasonal variation was observed in prescribing adherence, with significantly lower adherence in winter and spring months (adjusted odds ratio 0.60). A reduction of 12.9 DDDs between the pre- and post-intervention periods (p=0.0084) was documented, which represented a 19.3% decrease in antibiotic consumption.Conclusion. The study demonstrated that peer reviewed audit and feedback is an effective AMS intervention to improve antibiotic prescribing in primary care in a low-resource setting. The intervention, utilising existing resources and involving multidisciplinary engagement, may be incorporated into existing quality improvement processes at facility level, to ensure sustainable change

Detection and characterization of carbapenem resistant Gram-negative bacilli isolates recovered from hospitalized patients at Soba University Hospital, Sudan

BACKGROUND: Antimicrobial resistance (AMR) poses a complex threat to global health security and universal health coverage. Recently, nosocomial infections with carbapenemase-producing Gram-negative bacilli (GNB) is increasing worldwide. We report the molecular characterization and detection of genes associated with carbapenemase producing Gram negative bacteria isolated from hospitalized patients at Soba University Hospital (SUH) in Khartoum State, Sudan. RESULTS: Between October 2016 and February 2017, a total of 206 GNB clinical specimens were collected from hospitalized patients in SUH. Of 206 carbapenem resistance isolates, 171 (83 %) were confirmed as phenotypically resistant and 121 (58.7 %) isolates harboured one or more carbapenemase genes. New Delhi metallo-β-lactamase (NDM) types were the most predominant genes, blaNDM 107(52 %), followed by blaIMP 7 (3.4 %), blaOXA-48 5(2.4 %) and blaVIM 2 (0.9 %). Co-resistance genes with NDM producing GNB were detected in 87 (81.3 %) of all blaNDM producing isolates. NDM-1 was the most frequent subtype observed in 75 (70 %) blaNDM producing isolates. The highest percentage of resistance was recorded in ampicillin (98 %), cephalexin (93.5 %) amoxicillin clavulanic acid (90 %), cefotaxime (89.7 %), ceftriaxone (88.4 %), ceftazidime (84.2 %), sulfamethoxazole-trimethoprim (78.4 %) and nitrofurantoin (75.2 %), aztreonam (66 %) and temocillin (64 %). A close correlation between phenotypic and carbapenemase genes detection in all GNB was observed. CONCLUSIONS: The frequency of carbapenemase producing bacilli was found to be high in SUH. NDM was found to be the most prevalent carbapenemase gene among clinical isolates. Close surveillance across all hospitals in Sudan is required. The relative distribution of carbapenemase genes among GNB in nosocomial infections in Africa needs to be defined

Womens experiences of HIV testing and counselling in the labour ward: A case of Bwaila hospital

Introduction: HIV counseling and testing during labour can be emotional, but is important because it allows mothers and babies to receive PMTCT prophylaxis if previous identification of HIV infection has not occurred. The study explores how HIV testing and counseling during early labour affects women. Methodology: This was a qualitative exploratory study to understand women’s experiences during early labor. From September to October 2009, we conducted 10 indepth interviews with women who tested for HIV during early labour. We recruited women who tested > 3 months previously and those who had never tested for HIV from the postpartum ward of Bwaila Hospital. Data were analyzed manually using the life story approach in order to examine and analyse subjective experiences of women and their constructions of the social world. Transcripts were read multiple times to understand meanings which participants attached to their experiences. We coded data according to emerging themes and subthemes. Results: Ten women 20-35 years were interviewed. Eight women had unknown HIV status while two had known HIV results but re-tested to update their status. Four women were found HIV-positive while 6 were HIVnegative. The primary theme was that women appreciated and accepted HIV testing and counseling. Testing was accepted as a necessary step to protect the infant from HIV infection. Counseling was viewed as helpful for acceptance of HIV status. One key subtheme was that HIV positive women experienced disappointment about their HIV diagnosis, though this was outweighed by the knowledge that one could protect her infant. All women viewed the short time to complete the counseling and testing procedures as favourable. Conclusion: Labour testing is acceptable and should be promoted to enhance PMTCT services by identifying HIV positive women with unknown status. Counseling helps women to accept being found with HIV and seek appropriate services

Inheritance of resistance to Fusarium verticillioides ear rot in maize inbred lines of southern, west and central Africa origin

Open Access Article; Published online: 22 Jul 2022Maize (Zea mays L.) is an important crop in sub-Sahara Africa for both human consumption and livestock feed. Maize use is often limited by ear-rotting fungi, some of which produce deleterious secondary metabolites. The aim of this study was to determine the inheritance of resistance to Fusarium verticillioides as an indirect way of selecting for resistance to secondary metabolites such as the mycotoxin fumonisin that is produced by this fungus, under artificial inoculation and natural infection. Twelve inbred lines from Seed Co that were used as the females, were mated to 12 tester lines from the International Institute of Tropical Agriculture (IITA) that were used as males, using the North Carolina Design II. The resulting 144 F1 hybrids and six check hybrids were evaluated in Zimbabwe. Artificial inoculation with F. verticillioides was done at Rattray Arnold Research Station in the first season. The general (GCA) and specific combining ability (SCA) effects for F. verticillioides incidence were variable across sites for the lines and the testers. Six southern African inbred lines had desirable GCA for F. verticillioides ear rot and can be used as resistance sources. Outstanding testers from IITA that had negative GCA for F. verticillioides ear rot and fumonisins were identified. Both additive and nonadditive effects were implicated in resistance to ear rot caused by F. verticillioides and potential lines were identified that can be used in regional breeding programs

Bed net use among school-aged children after a universal bed net campaign in Malawi

Abstract Background Recent data from Malawi suggest that school-aged children (SAC), aged 5–15 years, have the highest prevalence of Plasmodium falciparum infection among all age groups. They are the least likely group to utilize insecticide-treated nets (ITNs), the most commonly available intervention to prevent malaria in Africa. This study examined the effects of a universal ITN distribution campaign, and their durability over time in SAC in Malawi. This study identified factors that influence net usage among SAC and how these factors changed over time. Methods Cross-sectional surveys using cluster random sampling were conducted at the end of each rainy and dry season in southern Malawi from 2012 to 2014; six surveys were done in total. Mass net distribution occurred between the first and second surveys. Data were collected on household and individual net usage as well as demographic information. Statistical analyses used generalized linear mixed models to account for clustering at the household and neighbourhood level. Results There were 7347 observations from SAC and 14,785 from young children and adults. SAC used nets significantly less frequently than the rest of the population (odds ratio (OR) from 0.14 to 0.38). The most important predictors of net usage among SAC were a lower ratio of people to nets in a household and higher proportion of nets that were hanging at the time of survey. Older SAC (11–15 years) were significantly less likely to use nets than younger SAC (5–10 years) [OR = 0.24 (95 % CI: 0.21, 0.28)]. The universal bed net campaign led to a statistically significant population-wide increase in net use, however net use returned to near baseline within 3 years. Conclusions This study suggests that a single universal net distribution campaign, in combination with routine distribution through health clinics is not sufficient to cause a sustained increase in net usage among SAC. Novel approaches to ITN distribution, such as school-based distribution, may be needed to address the high prevalence of infection in SAC.http://deepblue.lib.umich.edu/bitstream/2027.42/134523/1/12936_2016_Article_1178.pd

Incorporating Acute HIV Screening into Routine HIV Testing at Sexually Transmitted Infection Clinics, and HIV Testing and Counseling Centers in Lilongwe, Malawi

Background and Objectives:Integrating acute HIV-infection (AHI) testing into clinical settings is critical to prevent transmission, and realize potential treatment-as-prevention benefits. We evaluated acceptability of AHI testing and compared AHI prevalence at sexually transmitted infection (STI) clinics and HIV testing and counseling (HTC) clinics in Lilongwe, Malawi.Methods:We conducted HIV RNA testing for HIV-seronegative patients visiting STI and HTC clinics. AHI was defined as positive RNA and negative/discordant rapid antibody tests. We evaluated demographic, behavioral, and transmission-risk differences between STI and HTC patients and assessed performance of a risk-score for targeted screening.Results:Nearly two-thirds (62.8%, 9280/14,755) of eligible patients consented to AHI testing. We identified 59 persons with AHI (prevalence = 0.64%)–a 0.9% case-identification increase. Prevalence was higher at STI [1.03% (44/4255)] than at HTC clinics [0.3% (15/5025), P < 0.01], accounting for 2.3% of new diagnoses vs 0.3% at HTC clinic. Median viral load (VL) was 758,050 copies per milliliter; 25% (15/59) had VL ≥10,000,000 copies per milliliter. Median VL was higher at STI (1,000,000 copies/mL) compared with HTC (153,125 copies/mL, P = 0.2). Among persons with AHI, those tested at STI clinics were more likely to report genital sores compared with those tested at HTC clinics (54.6% vs 6.7%, P < 0.01). The risk score algorithm performed well in identifying persons with AHI at HTC clinics (sensitivity = 73%, specificity = 89%).Conclusions:The majority of patients consented to AHI testing. AHI prevalence was substantially higher in STI clinics than HTC clinics. Remarkably high VLs and concomitant genital scores demonstrate the potential for transmission. Universal AHI screening at STI clinics, and targeted screening at HTC centers, should be considered