Potentiometric study of complexes formed between (s)-α-amino-3-hydroxy-5-methyl-4-isoxazolepropanoic acid and some transition metal ions

Potentiometric study has been carried out on (S)--amino-3-hydroxy-5-methyl-4-isoxazolepropanoic acid [AMPA] in the presence of transition metal ions to measure the thermodynamic stabilities of its complexes; and hence give an insight into its possible role in binding metal ions. The nitrogen donor atom of AMPA is alanine-like with the addition of a hydroxy-isoxazole ring. The first complex [CuHL], which is fully formed by pH 4 is proposed to be with {N,O} bonding which results in the formation of a stable five membered chelate ring. The [CuL] species has some enhanced stability which suggest some form of tridentate co-ordination through {H2N, COO-, O-}. When this changes to [CuL2], one of these bonds must be broken if Cu(II) is to have a maximum co-ordination number of four. Zn and Cd formed very similar comlexes with AMPA, these were [ZnHL], [ZnL], [ZnL2] and [CdHL], [CdL], [CdL2], respectively. [ZnL] and [ZnL2] are significantly more stable than alanine, suggesting tri-dentate co-ordination. [CdHL] complex is again very important suggesting some bidentate chelation. KEY WORDS: (S)-a-Amino-3-hydroxy-5-methyl-4-isoxazolepropanoic acid, Transition metal ions, Thermodynamic stability constants, Potentiometry, Speciation  Bull. Chem. Soc. Ethiop. 2003, 17(1), 45-51

PRINCIPALS’ ROLE IN MONITORING INSTRUCTIONAL ASSESSMENT AND ITS INFLUENCE ON TEACHING AND LEARNING OUTCOME IN SECONDARY SCHOOLS IN KAJIADO COUNTY, KENYA

With the core business of the school being instruction, the principals’ monitoring of instructional assessment is necessary in enhancing teaching and learning processes and outcome in schools. Despite measures being in place, teaching and learning outcome has remained consistently low, especially in Kajiado County. The objective of this study is to assess the influence of principals’ monitoring of instructional assessments on teaching and learning outcome. The study was guided by the result-based management theory. The study employed a descriptive survey design. This study population of study comprised 727 respondents in all the 9 public secondary schools in Kajiado. These respondents included 122 teachers, 594 students and 9 principals. Out of these, 342 respondents were sampled and they were comprised of 9 principals, 97 teachers and 201 students. Proportionate sampling was used to draw a sample of 97 teachers’ and 201 students per school. Further, simple random sampling was used to sample teachers while convenience sampling was applied to draw the sample of students to participate in the study per school. Data was collected by questionnaires and interview schedule. A pilot study was conducted in two schools for the purpose of addressing validity and reliability of the instruments before the actual study was conducted. Content validity was determined by seeking the judgment of professional experts in the area of educational research, evaluation and assessment. Reliability level was ascertained by using Cronbach’s alpha technique to check internal consistency of the instruments. The analysis of quantitative data was done using frequencies, percentages and means and then presented in tables and figures. Qualitative data was arranged into themes and presented through narration and in verbatim. The study established that principals' checking of assessment practices, even-though inconsistent, significantly influenced performance. The study concluded that principals' monitoring of instructional practices (mean=3.5, SD=1.2) significantly influenced performance in schools. It recommended that the Ministry of Education should organise training for principals to improve their skills of monitoring assessment.  Article visualizations

Genetic characterization of influenza A(H3N2) viruses circulating in coastal Kenya, 2009-2017

Background Influenza viruses evolve rapidly and undergo immune driven selection, especially in the hemagglutinin (HA) protein. We report amino acid changes affecting antigenic epitopes and receptor‐binding sites of A(H3N2) viruses circulating in Kilifi, Kenya, from 2009 to 2017. Methods Next‐generation sequencing (NGS) was used to generate A(H3N2) virus genomic data from influenza‐positive specimens collected from hospital admissions and health facility outpatients presenting with acute respiratory illness to health facilities within the Kilifi Health and Demographic Surveillance System. Full‐length HA sequences were utilized to characterize A(H3N2) virus genetic and antigenic changes. Results From 186 (90 inpatient and 96 outpatient) influenza A virus‐positive specimens processed, 101 A(H3N2) virus whole genomes were obtained. Among viruses identified in inpatient specimens from 2009 to 2015, divergence of circulating A(H3N2) viruses from the vaccine strains A/Perth/16/2009, A/Texas/50/2012, and A/Switzerland/9715293/2013 formed 6 genetic clades (A/Victoria/208/2009‐like, 3B, 3C, 3C.2a, 4, and 7). Among viruses identified in outpatient specimens from 2015 to 2017, divergence of circulating A(H3N2) viruses from vaccine strain A/Hong Kong/4801/2014 formed clade 3C.2a, subclades 3C.2a2 and 3C.2a3, and subgroup 3C.2a1b. Several amino acid substitutions were associated with the continued genetic evolution of A(H3N2) strains in circulation. Conclusions Our results suggest continuing evolution of currently circulating A(H3N2) viruses in Kilifi, coastal Kenya and suggest the need for continuous genetic and antigenic viral surveillance of circulating seasonal influenza viruses with broad geographic representation to facilitate prompt and efficient selection of influenza strains for inclusion in future influenza vaccines

Robust estimation of variance in the presence of nearest neighbour imputation

The problem of estimating the variance of an estimator of the population total when missing values have been filled using a Nearest Neighbour (NN) imputation method is considered. The estimator is developed assuming a more general model than those considered in earlier studies. In an empirical study involving two artificial populations, the proposed estimator is found to perform better or as well as other two estimators in the current use. African Journal of Science and Technology Vol.4(2) 2003: 5-1

Factors Influencing the Adoption of Minimally Invasive Surgery

Background: Cost is a major concern for delivery of minimally invasive surgical technologies due to the nature of resources required. It is unclear whether factors extrinsic to technology availability impact on this uptake. Objectives: To establish the influence of institutional, patient and surgeon-related factors in the adoption of minimally invasive surgical technologies. Methods: Eighty surgeons in tier 4 hospitals in Nairobi were subjected to questionnaires and key informant interviews between January and May 2015. The respondents were required to cite one surgical procedure for which they had the option of either open or minimally invasive surgical approach (MIS). Of the factors presented, they were required to grade them from 1 for least recurring to 5 for most recurring. Results: The response rate was 100%. A total of 9 surgical interventions emerged from the respondents. The most common impediment to MIS was unavailability of the required equipment and non-functional equipment (mean score, 2.61). The most common patient related factors that led to an open approach were patient presentation, obesity, co-morbidities and age (mean score 2.87). The most common surgeon related factor was lack of confidence in the MIS approach (mean score, 2.55). Conclusions: Absence of enabling functional equipment or device at the time of surgery is the most significant institutional factor that impedes the adoption of MIS. Intraoperative complications and the surgeon’s comfort emerged as the most significant patient and surgeon factors respectively.Keywords: Minimally Invasive Surgical Approaches, Health System Pillars, Service Delivery

Human metapneumovirus prevalence and patterns of subgroup persistence identified through surveillance of pediatric pneumonia hospital admissions in coastal Kenya, 2007–2016

Background Human metapneumovirus (HMPV) is an important respiratory pathogen that causes seasonal epidemics of acute respiratory illness and contributes significantly to childhood pneumonia. Current knowledge and understanding on its patterns of spread, prevalence and persistence in communities in low resource settings is limited. Methods We present findings of a molecular-epidemiological analysis of nasal samples from children < 5 years of age admitted with syndromic pneumonia between 2007 and 2016 to Kilifi County Hospital, coastal Kenya. HMPV infection was detected using real-time RT-PCR and positives sequenced in the fusion (F) and attachment (G) genes followed by phylogenetic analysis. The association between disease severity and HMPV subgroup was assessed using Fisher’s exact test. Results Over 10 years, 274/6756 (4.1%) samples screened were HMPV positive. Annual prevalence fluctuated between years ranging 1.2 to 8.7% and lowest in the recent years (2014–2016). HMPV detections were most frequent between October of one year to April of the following year. Genotyping was successful for 205/274 (74.8%) positives revealing clades A2b (41.0%) and A2c (10.7%), and subgroups B1 (23.4%) and B2 (24.9%). The dominance patterns were: clade A2b between 2007 and 11, subgroup B1 between 2012 and 14, and clade A2c in more recent epidemics. Subgroup B2 viruses were present in all the years. Temporal phylogenetic clustering within the subgroups for both local and global sequence data was seen. Subgroups occurring in each epidemic season were comprised of multiple variants. Pneumonia severity did not vary by subgroup (p = 0.264). In both the F and G gene, the sequenced regions were found to be predominantly under purifying selection. Conclusion Subgroup patterns from this rural African setting temporally map with global strain distribution, suggesting a well-mixed global virus transmission pool of HMPV. Persistence in the local community is characterized by repeated introductions of HMPV variants from the global pool. The factors underlying the declining prevalence of HMPV in this population should be investigated

Policy Brief on Inclusion of Water, Sanitation and Hygiene in Zambia`s Nationally Determined Contributions

The Paris Agreement aims to reduce Greenhouse Gas (GHG) emissions, thus contributing to sustainable development goals through building climate-resilient communities and industries. Water is the primary medium through which climate change influences the earth’s ecosystem and thus the livelihood and well-being of societies. Extreme weather conditions impact many sectors such as health, tourism, agriculture, and industry where water plays a key role. The climate effect is first and foremost through water systems as highlighted by the World Economic Forum (2016) Global Risks Report. Hence the Water, Sanitation, and Hygiene (WASH) sector plays a pivotal role in addressing climate change. In the last decade, Zambia has experienced the impacts of climate change in the form of extreme weather conditions and rising temperatures. In light of this, the Zambian government developed NDCs in accordance with the Paris agreement that aims to reduce Greenhouse Gas (GHG) emissions and develop sustainable climate-resilient communities and industries. The impacts of climate change are felt through its influence on water. WASH is not only affected by climate change, but also a contributing factor to GHG emissions. Therefore, the WASH sector should play a pivotal role in contributing to the climate change targets. There are gaps among state and non-state actors and with affected communities in acknowledging the critical role of WASH in making real the NDC that need bridging. These include awareness and knowledge of WASH in contributing to NDC; the need to go beyond water to include sanitation and hygiene elements in the NDCs as holistic approach; inclusive participation of civil society and other non-state actors in addressing the gaps; integration of sectors and programmes in the NDCs; and enhanced governance and accountability mechanisms

Carpet characteristics of eichhornia crassipes [mart.] solms (water hyacinth) in the Winam gulf (lake victoria, Kenya)

The occurrence and spread of the water hyacinth (Eichhornia crassipes [Mart.] Solms), in the Winam gulf has created numerous attributes to the human population that live around the lake, thereby making its control a priority. Navigation within the lake is a major economic activity that has been greatly affected. Before this study, little was known about the characteristics of these weed carpets, and specifically the weight that a healthy inter-connected or entangled carpet can support before it was able to sink or even get submerged. Can a light herbivore or human stranded in the lake walk on a healthy carpet to safety?. In order to better understand these unknown, a study was initiated at five locations (i.e; Dunga beach, Kisumu pier, Kusa, Kobala and Kendu bay) within the lake that appeared to contain healthy dense carpets. Carpet connectivity, mat buoyancy, distribution of mass, biomass density, rhizome length and population density were calculated. Carpet connectivity was determined as the difference in pressure when weights were added on a mesh wire measuring 0.434m2 until the carpet submerged and the pressure on the same carpet that was required to submerge it after a complete disconnection. Standing population density was determined by counting the number of plants found within quadrants measuring 1 m2; while biomass density was determined when oven dried plant materials collected from quadrants measuring 1 m2 was weighed. Plant mass and rhizome length measurements were correlated, while population density was correlated to biomass density. These observations show that water hyacinth distribution in the Winam gulf is seasonal and adopts residence in secluded bays, carpets measuring 0,434m2 in size that have a connectivity of 288.4 Pa (pascals) are able to support a weight of only 12.6 kg, with any additional weight causing them to submerge. Distribution of mass was normal except in locations that are subjected to external factors

Revitalizing Water, Sanitation, and Hygiene in Uganda’s National Determined Contributions` 2021 Revision Process- A Policy Brief

Uganda as a signatory to the Paris Agreement is required to update her Nationally Determined Contributions to demonstrate progress after every five years. The Water Sanitation and Hygiene(WASH) sector has proven to be a victim, contributor but also a critical component to addressing the existing climate challenges. Despite the clear link between WASH and Climate change, most climate change initiatives do not address WASH adequately from both adaptation and mitigation perspectives. This study analyzed the WASH related targets in Uganda’s current NDCs to ascertain how they have been addressed from both the mitigation and adaptation perspectives. The paper took on a rapid assessment of the current NDCs using a desk study and secondary literature review approach coupled with key stakeholder expert inputs through write-shops. Whereas WASH climate focused targets have been to a greater extent covered under adaptation, there is limited integration from the mitigation perspective which does not provide a balanced approach towards achieving the targets set out in the NDCs. The policy brief recommends a number of actions that include inclusion of WASH mitigation policy action in the NDCs, setting adaptation targets for the waste sector, amplifying the role of the private sector in WASH in the updated NDCs, prioritizing research and development to support decision making, providing for measurement, reporting and verifications for WASH in the NDCs, enhanced technology transfer and alignment of the updated NDCs with the long-term strategy. If adopted, these recommendations provide a starting point to comprehensively address WASH in the revised NDCs and subsequently contribute to the achievement of goal six of Sustainable Development Goals on clean water and sanitation for all