46 research outputs found
Modulation of energy homeostasis in maize and Arabidopsis to develop lines that are tolerant to drought, genotoxic and oxidative stresses
Modulation of energy homeostasis in maize and Arabidopsis to develop lines tolerant to drought, genotoxic and oxidative stresses
Abiotic stresses cause crop losses worldwide that reduce the average yield by more than 50%. Due to the high energy consumed to enhance the respiration rates, the excessive reactive oxygen species release provokes cell death and, ultimately, whole plant decay. A metabolic engineering approach in maize (Zea mays) altered the expression of two poly(ADP-ribosyl)ation metabolic pathway proteins, poly(ADP-ribose) polymerase (PARP) and ADP-ribose-specifIc Nudix hydrolase (NUDX) genes that play a role in the maintenance of the energy homeostasis during stresses. By means of RNAi hairpin silencing and CRISPR/Cas9 gene editing strategies, the PARP expression in maize was downregulated or knocked down. The Arabidopsis NUDX7 gene and its two maize homologs, ZmNUDX2 and ZmNUDX8, were overexpressed in maize and Arabidopsis. Novel phenotypes were observed, such as significant tolerance to oxidative stress and improved yield in Arabidopsis and a trend of tolerance to mild drought stress in maize and in Arabidopsis. Key words: poly(ADP-ribose) polymerase, Nudix hydrolase, CRISPR/Cas9, maize, oxidative stress, drought stress
The Effect of Quality of Service on Customersâ Loyalty to Financial Institutions: A Survey of Financial Institutions in Nyahururu Town, Kenya
The financial institutions in Nyahururu have experienced a scenario in which customers shift loyalty to different institutions over time, a situation that has led to managersâ complaints on matters of customersâ retention. This study aimed at examining the factors that influence customer loyalty to financial institutions in Nyahururu town. The study objective was to examine the effect of quality of service on customersâ loyalty to financial institutions. The study was based on the Loyalty Business Model as advocated for by Strorback, Strandvik, & Gronroos, (1994) and customer loyalty theory by Reynolds (2015). Descriptive survey design was applied with a target a population of 28860 staff members and customers served by the 6 Micro-Finance institutions in Nyahururu, Kenya. A stratified sampling method was applied to obtain 384 staff members and customers from 6 Micro- finance institutions in Nyahururu Town. Primary data was collected through the use of questionnaires. The data collected was sorted and then coded before analysis. Data was analyzed quantitatively and qualitatively. In descriptive data analysis, mean, standard deviation and percentages were used. The SPSS computer program was used to aid in analysis. Multiple linear regression and correlation model was also used to analyze data by establishing the interrelationships between independent and dependent variable. Implementing the recommendations from the study would be useful to financial institutions seeking to improve the customer loyalty. This research study has also contributed to the body of knowledge on the best practices of retaining customers within financial institutions. Keywords: Customerâs loyalty, Customer Loyalty, Customerâs retention, Financial Institutions, quality of servic
Pyrethrins In Soil and Water From Selected Pyrethrum Growing Areas In Nakuru County, Kenya
Introduction: Pyrethrum also known as Chrysanthemum is a plant from which compounds known as pyrethrins are derived. The pyrethrins have been used for many years as insecticides. Incidentally due to their high instability they have slowly been replaced by synthetic pyrethroids. Pyrethrins are generally regarded as safe compared to the pyrethroids. However, the amounts released into the environment have not been well documented especially in pyrethrum growing regions.Objective: The aim of the study was to determine the concentration of pyrethrins that come from pyrethrum plants and released into the environment through their use as insecticides, thus, into drinking water and soil, in pyrethrum growing regions in Kenya.Methodology: Quantification to amounts of pyrethrins from pyrethrum plants, in soil and water bodies in and around pyrethrum farms in Kiambogo and Naivasha (Nakuru County). The study was carried out using High Performance Liquid Chromatography (HPLC). Water samples (0.5L) were collected from the following water bodies: rivers, streams, dams, wells and boreholes near or within pyrethrum farms.Conclusion: It was established that, the quantity of pyrethrins present in water and soil samples werebelow detectable levels within the WHO recommended range. Hence safe for the environment,more so for the farmers and the people living around pyrethrum farms.
Key words: Pyrethrum, pyrethrins, chromatography, water, soil
Experiences and perspectives on Spodoptera frugiperda (Lepidoptera: Noctuidae) management in Sub-Saharan Africa
It has been over five years since the first report of an outbreak of the fall armyworm, Spodoptera frugiperda
(J.E. Smith) (Lepidoptera: Noctuidae) in Africa. The highly invasive pest, native to the Americas, has since spread
across the African continent attacking many crops and causing significant yield loss to Africaâs staple crop, maize.
From the onset of the outbreak, there have been massive and varied responses from farmers, governments and
nongovernmental organizations. This mini-review provides various perspectives on S. frugiperda control in sub-
Saharan Africa, building on previously published evidence, and experiences of the authors. It also highlights new
technologies and lessons learned so far from the S. frugiperda outbreaks in sub-Saharan Africa, based on which
suggestions on possible integrated management approaches are proffered.The National Research Foundation of South Africahttps://academic.oup.com/jipmam2022Forestry and Agricultural Biotechnology Institute (FABI
Lessons learnt from the first controlled human malaria infection study conducted in Nairobi, Kenya
Tobacco use among a population of women attending cervical cancer screening programs in primary health care clinics in South Africa : a cross-sectional study
TABLES :TABLE 1: characteristics of women (N=749) attending pap smears at primary health care clinics in Gauteng Province, South Africa (September 2018-September 2019). TABLE 2: tobacco use characteristics of women (N=749) attending pap smears in primary health care clinics in Gauteng Province, South Africa (September 2018-September 2019). TABLE 3: factors associated with ever tobacco use among women attending pap smears at primary health care facilities in Gauteng Province (September 2018-September 2019). TABLE 4: factors associated with current tobacco use among women attending pap smears at primary health care facilities in Gauteng Province (September 2018-September 2019).INTRODUCTION : we determined the prevalence, patterns and factors associated with tobacco use among women presenting for cervical cancer screening in primary health care clinics in Gauteng province, South Africa. METHODS : this study utilized data from an ongoing cross-sectional study commenced in September 2018, in which 749 participants had responded to an interviewer-administered semi-structured questionnaire on socio-demographics, HIV status, tobacco use, family planning methods, sexual and cervical cancer screening behaviours. Data were entered into the web-based research electronic data capture (REDCap). We performed descriptive data analysis and included multivariate logistic regression. We considered a p-value < 0.05 statistically significant. RESULTS : participantsÂŽ median age was 38 years (interquartile range: 31-38) with 43.9% (328) reporting being HIV-positive. The prevalence of ever and current tobacco use were 24.3% (182/749) and 17.1% (128/749) respectively. In multivariable logistic regression, participants who self-identified as racial ethnicity other than Black African and those who were HIV positive and not on antiretroviral treatment, had increased odds of reporting current tobacco use ((adjusted odds ratio (AOR)= 5.6, 95% CI: 3.2-9.8) and (AOR= 8.2, 95% CI: 2.0-34.1) respectively). CONCLUSION : current tobacco use is common among women attending cervical cancer screening programs in primary health care clinics in Gauteng Province. Furthermore, study findings suggest the need to integrate tobacco cessation treatments into womenÂŽs health and HIV treatment programs.Department of Family Medicine and Primary Care Project FHP 000 and National Research Foundation.http://www.panafrican-med-journal.comam2023Family Medicin
Improved Neurodevelopment After Initiation of Antiretroviral Therapy in Human Immunodeficiency Virus-infected Children
Draft genome sequence of Solanum aethiopicum provides insights into disease resistance, drought tolerance, and the evolution of the genome
The African eggplant (Solanum aethiopicum) is a nutritious traditional vegetable used in many African countries,
including Uganda and Nigeria. It is thought to have been domesticated in Africa from its wild relative, Solanum anguivi. S.aethiopicum has been routinely used as a source of disease resistance genes for several Solanaceae crops, including Solanum
melongena. A lack of genomic resources has meant that breeding of S. aethiopicum has lagged behind other vegetable crops.
Results: We assembled a 1.02-Gb draft genome of S. aethiopicum, which contained predominantly repetitive sequences
(78.9%). We annotated 37,681 gene models, including 34,906 protein-coding genes. Expansion of disease resistance genes
was observed via 2 rounds of amplification of long terminal repeat retrotransposons, which may have occurred âŒ1.25 and
3.5 million years ago, respectively. By resequencing 65 S. aethiopicum and S. anguivi genotypes, 18,614,838 single-nucleotide
polymorphisms were identified, of which 34,171 were located within disease resistance genes. Analysis of domestication
and demographic history revealed active selection for genes involved in drought tolerance in both âGiloâ and âShumâ
groups. A pan-genome of S. aethiopicum was assembled, containing 51,351 protein-coding genes; 7,069 of these genes were
missing from the reference genome. Conclusions: The genome sequence of S. aethiopicum enhances our understanding of
its biotic and abiotic resistance. The single-nucleotide polymorphisms identified are immediately available for use by
breeders. The information provided here will accelerate selection and breeding of the African eggplant, as well as other
crops within the Solanaceae family
Development of a Clinical Prediction Score Including Monocyte-to-Lymphocyte Ratio to Inform Tuberculosis Treatment Among Children With HIV: A Multicountry Study
BACKGROUND: Clinical pediatric tuberculosis (TB) diagnosis may lead to overdiagnosis particularly among children with human immunodeficiency virus (CHIV). We assessed the performance of monocyte-lymphocyte ratio (MLR) as a diagnostic biomarker and constructed a clinical prediction score to improve specificity of TB diagnosis in CHIV with limited access to microbiologic testing. METHODS: We pooled data from cohorts of children aged â€13 years from Vietnam, Cameroon, and South Africa to validate the use of MLR â„0.378, previously found as a TB diagnostic marker among CHIV. Using multivariable logistic regression, we created an internally validated prediction score for diagnosis of TB disease in CHIV. RESULTS: The combined cohort had 601 children (median age, 1.9 [interquartile range, 0.9-5.3] years); 300 (50%) children were male, and 283 (47%) had HIV. Elevated MLR â„0.378 had sensitivity of 36% (95% confidence interval [CI], 23%-51%) and specificity of 79% (95% CI, 71%-86%) among CHIV in the validation cohort. A model using MLR â„0.28, age â„4 years, tuberculin skin testing â„5â
mm, TB contact history, fever >2 weeks, and chest radiograph suggestive of TB predicted active TB disease in CHIV with an area under the receiver operating characteristic curve of 0.85. A prediction score of â„5 points had a sensitivity of 94% and specificity of 48% to identify confirmed TB, and a sensitivity of 82% and specificity of 48% to identify confirmed and unconfirmed TB groups combined. CONCLUSIONS: Our score has comparable sensitivity and specificity to algorithms including microbiological testing and should enable clinicians to rapidly initiate TB treatment among CHIV when microbiological testing is unavailable