Department of Pharmacology and Toxicology, University of Nairobi, Kenya. The relative bioavailabilities of three carbamazepine tablet formulations available in the Kenyan market (Temporal(R), Taver(R) and Carbamazepine Lincoln) compared with the innovator formulation (Tegretol(R)) were evaluated in seven healthy African volunteers (5 males, two females; aged 22-36 years), according to a randomised fourway crossover study design, following oral administration of single 200 mg doses with a three week washout period. In vitro dissolution profiles of the tablets were also evaluated. Relative bioavailabilities ((F)rel) of Temporal(R), Taver(R) and Carbamazepine Linocoln were 101.2%, 82.2% and 71.6% respectively, compared with Tegretol(R). Percent drug content dissolved in vitro after I hour were 91.3%, 75.9% and 39.3% for Temporal(R), Taver(R) and Carbamazepine Lincoln, respectively. It was concluded that Temporal(R) was bioequivalent to Tegretol(R) while Taver(R) and Carbamazepin Lincoln were bioinequivalent to Tegretol(R). Administration of Taver(R) or Carbamazepine Lincoln might lead to poor control of epileptic seizures.

Department of Pharmacology and Toxicology, University of Nairobi, Kenya. The relative bioavailabilities of three carbamazepine tablet formulations available in the Kenyan market (Temporal(R), Taver(R) and Carbamazepine Lincoln) compared with the innovator formulation (Tegretol(R)) were evaluated in seven healthy African volunteers (5 males, two females; aged 22-36 years), according to a randomised fourway crossover study design, following oral administration of single 200 mg doses with a three week washout period. In vitro dissolution profiles of the tablets were also evaluated. Relative bioavailabilities ((F)rel) of Temporal(R), Taver(R) and Carbamazepine Linocoln were 101.2%, 82.2% and 71.6% respectively, compared with Tegretol(R). Percent drug content dissolved in vitro after I hour were 91.3%, 75.9% and 39.3% for Temporal(R), Taver(R) and Carbamazepine Lincoln, respectively. It was concluded that Temporal(R) was bioequivalent to Tegretol(R) while Taver(R) and Carbamazepin Lincoln were bioinequivalent to Tegretol(R). Administration of Taver(R) or Carbamazepine Lincoln might lead to poor control of epileptic seizures.

Department of Pharmacology and Toxicology, University of Nairobi, Kenya. The relative bioavailabilities of three carbamazepine tablet formulations available in the Kenyan market (Temporal(R), Taver(R) and Carbamazepine Lincoln) compared with the innovator formulation (Tegretol(R)) were evaluated in seven healthy African volunteers (5 males, two females; aged 22-36 years), according to a randomised fourway crossover study design, following oral administration of single 200 mg doses with a three week washout period. In vitro dissolution profiles of the tablets were also evaluated. Relative bioavailabilities ((F)rel) of Temporal(R), Taver(R) and Carbamazepine Linocoln were 101.2%, 82.2% and 71.6% respectively, compared with Tegretol(R). Percent drug content dissolved in vitro after I hour were 91.3%, 75.9% and 39.3% for Temporal(R), Taver(R) and Carbamazepine Lincoln, respectively. It was concluded that Temporal(R) was bioequivalent to Tegretol(R) while Taver(R) and Carbamazepin Lincoln were bioinequivalent to Tegretol(R). Administration of Taver(R) or Carbamazepine Lincoln might lead to poor control of epileptic seizures.

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Century is a model of terrestrial biogeochemistry based on relationships between climate, human management (fire, grazing), soil properties, plant productivity, and decomposition. The grassland version of the Century model was tested using observed data from 11 temperate and tropical grasslands around the world. The results show that soil C and N levels can be simulated to within ±25% of the observed values (100 and 75% of the time, respectively) for a diverse set of soils. Peak live biomass and plant production can be simulated within ± 25% of the observed values (57 and 60% of the time, respectively) for burned, fertilized, and irrigated grassland sites where precipitation ranged from 22 to over 150 cm. Live biomass can be generally predicted to within ±50% of the observed values (57% of the time). The model underestimated the live biomass in extremely high plant production years at two of the Russian sites. A comparison of Century model results with statistical models showed that the Century model had slightly higher r2 values than the statistical models. Data and calibrated model results from this study are useful for analysis and description of grassland carbon dynamics, and as a reference point for testing more physiologically based models prediction's of net primary production and biomass. Results indicate that prediction of plant and soil organic matter (C and N) dynamics requires knowledge of climate, soil texture, and N inputs.

C1 neurotoxin of Clostridium botulinum strains C-Stockholm (C-ST), C beta-Yoichi, C-468, CD6F, and C-CB19 and type D toxin of strains D-1873 and D-CB16 were purified by gel filtration, ion exchange, and affinity chromatographies. The purified toxins had di-chain structure made of heavy and light chains. The toxins of C beta-Yoichi, C-468, CD6F, and C-CB19 reacted with anti-C-ST heavy chain and anti-C-ST light chain in immunodiffusion tests and enzyme-linked immunosorbent assay, whereas D-CB16 toxin reacted with anti-D-1873 heavy chain and anti-D-1873 light chain. However, C-6813 toxin reacted with anti-D-1873 heavy chain and anti-C-ST light chain but not with anti-C-ST heavy chain or anti-D-1873 light chain immunoglobulin G. These results indicate common antigens in the heavy chains of C-6813 and D-1873 toxins and in the light chains of C-6813 and C-ST toxins. Further, they provide evidence for heterogeneity within type C1 toxin subunits.

A model for the establishment of an integrated geodetic datum covering a region is treated. The integrated geodetic datum is understood here to comprise the geoid, the reference ellipsoid, and the positional coordinates. A comprehensive unified solution model including the three parameters comprising the datum is considered. The estimation model adopted rigorously incorporates determined prior information in the estimation of the datum parameters. Mathematical models together with the pertinent observation equations are presented, followed by a description of the procedure for the aetual setting up of the datum. The observational scheme is based on a system of modular traverses anchored on a trilateration of GPS baselines.

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C1 neurotoxin of Clostridium botulinum strains C-Stockholm (C-ST), C beta-Yoichi, C-468, CD6F, and C-CB19 and type D toxin of strains D-1873 and D-CB16 were purified by gel filtration, ion exchange, and affinity chromatographies. The purified toxins had di-chain structure made of heavy and light chains. The toxins of C beta-Yoichi, C-468, CD6F, and C-CB19 reacted with anti-C-ST heavy chain and anti-C-ST light chain in immunodiffusion tests and enzyme-linked immunosorbent assay, whereas D-CB16 toxin reacted with anti-D-1873 heavy chain and anti-D-1873 light chain. However, C-6813 toxin reacted with anti-D-1873 heavy chain and anti-C-ST light chain but not with anti-C-ST heavy chain or anti-D-1873 light chain immunoglobulin G. These results indicate common antigens in the heavy chains of C-6813 and D-1873 toxins and in the light chains of C-6813 and C-ST toxins. Further, they provide evidence for heterogeneity within type C1 toxin subunits.

BackgroundOsgood-Schlatter disease is a common cause of anterior knee pain inthe adolescent. Treatment is usually conservative with surgery reservedfor those who do not respond to this treatment. There is little publishedwork regarding the experience with the disease in our local set up. This series documents the experience with 35 adolescents treated for the disease.DesignCase seriesSubjectsThirty five adolescents with clinical and radiological diagnoses ofOsgood-Schlatter disease at Nairobi and Kenyatta National Hospitals,between 2001and 2007.MethodPatients were evaluated for demographics, knee involvement, activitiesassociated with pain and treatment outcomeResultsThere were 28 males and 7 females, aged 10 to 16 years (mean 12.8years). Thirteen had bilateral knee involvement. Twenty two were involved in active sports while the rest had constant pain and unable to sit or kneel. A family history of the disease was documented in one case.Thirty adolescents responded well to the conservative treatment. Inthe five adolescents who underwent surgery, the patella tendon wasedematous with thickening of the tendon sheath and neovascularisation.All the operated adolescents returned to active sports with 6 weeks after the surgery.ConclusionOsgood-Schlatter disease is a self-limiting condition in majority ofadolescents. Surgery when indicated has an excellent outcome.

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Sub-Saharan Africa is home to 12% of the global population, and 4.3 million are blind and over 15 million are visually impaired. There are only 2.5 ophthalmologists per million people in SSA. Training of ophthalmologists is critical. We designed a systematic literature review protocol, searched MEDLINE Ovid and Embase OVID on 1 August 2019 and limited these searches to the year 2000 onwards. We also searched Google Scholar and websites of ophthalmic institutions for additional information. We include a total of 49 references in this review and used a narrative approach to synthesise the results. There are 56 training institutions for ophthalmologists in eleven Anglophone, eleven Francophone, and two Lusophone SSA countries. The median duration of ophthalmology training programmes was 4 years. Most curricula have been regionally standardised. National, regional and international collaborations are a key feature to ophthalmology training in more than half of ophthalmology training programmes. There is a drive, although perhaps not always evidence-based, for sub-specialisation in the region. Available published scientific data on ophthalmic medical and surgical training in SSA is sparse, especially for Francophone and Lusophone countries. However, through a broad scoping review strategy it has been possible to obtain a valuable and detailed view of ophthalmology training in SSA. Training of ophthalmologists is a complex and multi-faceted task. There are challenges in appropriate selection, capacity, and funding of available training institutions. Numerous learning outcomes demand curriculum, time, faculty, support, and appropriate assessment. There are opportunities provided by modern training approaches. Partnership is key.

Description
Polybrominated diphenyl ethers are linked to adverse health effects that includethyroid hormone disruption, neuro-developmental deficit, abnormal pregnancy, and potential carcinogens. This study was aimed at assessing the concentrationsof selected Polybrominated diphenyl ether compounds in water of Nairobi River. Water samples were collected by grab method from nine sites along the river andanalysed for brominated diphenyl ethers using gas chromatography coupled withmass spectrometer. The mean concentration of polybrominated diphenyl ethersresidue in water ranged from< 0.0009 to 72.89±6.15 ng/L. The dominantcongeners were 2, 2′, 4, 4′-tetra-bromodiphenyl ether, 2, 2′, 4, 4′, 5, 5′-hexabromodiphenylether, 2, 2′, 4, 4′, 6-penta-bromodiphenyl ether, 2, 2′, 4, 4′, 5, 5′-hexabromodiphenylether and 2, 2′, 4, 4′, 5, 6′-hexa-bromodiphenyl. The highest meanconcentration of 2, 2′, 4, 4′-tetra-bromodiphenyl ether was 72.89±6.15 ng/L, 2, 2′, 3, 4, 4′-penta-bromodiphenyl ether was 14.08±0.68 ng/L, 2, 2′, 4, 4′, 6-pentabromodiphenylether was 43.67±1.47 ng/L, 2, 2′, 4, 4′, 5, 5′-hexa-bromodiphenylether was 24.78±2.49 ng/L, and 2, 2′, 3, 4, 4′, 5′, 6-hepta-bromodiphenyl ether was11. 75±0.97 ng/L. Consequently, as these compounds are known to bioaccumulatein fatty tissues, continued use of the river water poses a health risk toanimals and humans due to contamination across the food chain.

This research paper focuses on the optimization of the input parameters used in the computer numerical controlled (CNC) milling of polypropylene + 60 wt% quarry dust composite. The efficiency and profitability of the cutting operation was assessed using the material removal rate (MRR). Finding the optimal and suitable parameters to use in the cutting of polypropylene + 60 wt% quarry dust composite is crucial when it comes to increasing productivity without increasing the cost of production and machining time. Therefore, the Taguchi technique was utilized to optimize the cutting speed, the feed rate and the depth of cut used while focusing on their effects on the material removal rate. The analysis of the input parameters was carried out using the L9 Taguchi orthogonal array, the signal-to-noise (S/N) ratio and the analysis of variance (ANOVA). The finding showed that the optimal milling parameters for efficient productivity were; the cutting speed of 600 rpm, a feed rate of 200 mm/min and depth of cut of 0.8 mm. Additionally, the feed rate is the most contributing factor in affecting the material removal rate, followed by the depth of cut and lastly the cutting speed at 53%, 17 and 10% respectively.

Among the several techniques for additive manufacturing (AM), fused deposition modelling (FDM) is widely used. Fused deposition modelling process uses a thermoplastic material, which is melted and then extruded layer by layer through a nozzle, in order to create a three-dimensional object. As a result of the default setting of process parameters provided by the manufacturers, produced parts normally have a poor surface finish, low mechanical properties, low dimensional accuracy, and increased residual stresses compared to the parts produced using conventional manufacturing processes like molding (casting). Qualities of fused deposition modelled (FDMed) parts are generally affected by process parameters including the layer thickness, extrusion temperature, build orientation, printing speed, raster angle, infill density, raster width, nozzle diameter, and air gap. Increasing infill density, printing temperature, and decreasing print speed and layer thickness lead to increase mechanical strength and improve the surface finish of the printed parts. The optimal process parameters are preferred to achieve superior properties of the parts. This paper reviews the optimal fused deposition modelling process parameters on part qualities for making the stability of used deposition modelled parts for use. Various process parameters are identified in order to obtain desirable qualities in the manufactured parts. Areas for future research are proposed.

This study is based on the optimization of the parameters that influence the computer numerical control (CNC) milling operation during the machining of polypropylene+60wt.% quarry dust composite. The input parameters studied are the cutting speed, the feed rate and the depth of cut. These input parameters were optimized using the Taguchi optimization technique with the output response taken into consideration was the surface roughness. An L9 orthogonal array (OA) was selected and formulated in a commercial software Minitab 19 based on three factors and three levels combination. The signal-to-noise (S/N) ratio was analysed to give a combination of values of the input parameters that produced optimum results for surface roughness. The analysis of variance (ANOVA) was then conducted to determine the significance and percentage contribution of each parameter. From the results, the optimum values obtained were cutting speed of 1000 rpm, feeding rate of 120 mm/min and depth of cut of either 0.5 mm or 0.8 mm. The cutting speed had the highest contribution towards the surface roughness at 81.98%, followed by the depth of cut at 7.43% and the feed rate having the least contribution at 3.69%.

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MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.

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To describe ocular surface disorders associated with human immunodeficiency virus (HIV). : Narrative review. : Ocular surface neoplastic conditions, such as Kaposi's sarcoma, conjunctival lymphoma and ocular squamous cell carcinoma along with blepharitis, dry eye disease, and vernal keratoconjunctivitis, constitute ocular surface complications in HIV-infected individuals. : This review will provide a summary of clinical presentations and treatment options for the most common HIV-related ocular surface diseases, indicating the need for a comprehensive ocular examination including ocular surface in all HIV patients.

Obstructive sleep apnea (OSA) is a significant health problem among adults and children globally, resulting in decreased quality of life and increased costs of healthcare. For optimal clinical care, primary care physicians should be familiar with OSA and confident in their ability to screen, diagnose, and manage this condition. To assess the knowledge, attitudes, and practices of primary care physicians in Kenya, Nigeria, and South Africa regarding OSA in adults and children. We conducted a multicenter cross-sectional survey in Kenya (Nairobi), Nigeria (Edo State), and South Africa (Cape Town) between April 2016 and July 2017. At least 40 participants were randomly selected from a register of primary care physicians at each site. Potential participants were contacted to receive online/paper-based, validated OSA Knowledge and Attitudes (OSAKA) and OSAKA in Children (OSAKA-KIDS) questionnaires related to adults and children, respectively. The median percentage knowledge scores and proportions of favorable attitude were computed and current diagnostic and referral practices were documented. The median OSAKA knowledge scores were 83.3% (interquartile range [IQR], 77.8-88.9), 66.7% (IQR, 55.6-77.8), and 61.1% (IQR, 55.6-77.8) among South African, Kenyan, and Nigerian physicians, respectively. For OSAKA-KIDS, the median knowledge scores were 61.1% (IQR, 50.0-72.2), 64.2% (IQR, 35.3-93.2), and 58.3% (IQR, 44.4-66.7) among South African, Kenyan, and Nigerian physicians, respectively. Most physicians (90-94%) considered adult and pediatric OSA very/extremely important. Fewer physicians agreed/strongly agreed that they were confident about OSA diagnosis (55%), management (25%), and continuous positive airway pressure (18%) use in adults. Even fewer physicians agreed/strongly agreed that they were confident about pediatric OSA diagnosis (35%), management (21%), and continuous positive airway pressure use (18%). South African physicians mainly prescribed polysomnography (51%) and overnight oximetry (22%), whereas 49% of Nigerian physicians and 65% of Kenyan physicians commonly requested lateral cervical radiography. Primary care physicians in South Africa, Nigeria, and Kenya considered OSA to be important but had modest knowledge about OSA in adults and children, and had a low perceived confidence in adult and pediatric management. Focused educational interventions during undergraduate training and continuing professional development programs may improve primary physicians' knowledge about OSA and its diagnosis and management.

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It is a well-known result in operator theory that whenever two operators are similar then they have equal spectra even though they do not have to belong to the same class of operators. However under a stronger relation of unitary equivalence it can be shown that two unitarily equivalent operators may belong to the same class of op erators. In this paper we endeavor to exhibit results on such classes of operators which belong to same class under unitary equivalence.

Abstract
Kenyan communities are exposed to natural disasters by an amalgamation of factors such as poverty, aridity, and settlements in areas susceptible to natural disasters or in areas with poor infrastructure. This is expected to increase due to the effects of climate change. In an attempt to explain some of these variabilities, we model the extreme damages from natural disasters in Kenya by developing a compound distribution that takes into account both the frequency and the severity of the extreme events. The resulting distribution is based on a threshold model and compound extreme value distribution. For frequency of events exceeding a threshold of 150,000, we found that it follows a negative binomial distribution, while severity of exceedance follows a generalized Pareto distribution. This distribution fits the data well and is found to be a better model for natural disasters in Kenya than the traditional extreme value threshold model.

Kenyan communities are exposed to natural disasters by an amalgamation of factors such as poverty, aridity, and settlements in areas susceptible to natural disasters or in areas with poor infrastructure. This is expected to increase due to the effects of climate change. In an attempt to explain some of these variabilities, we model the extreme damages from natural disasters in Kenya by developing a compound distribution that takes into account both the frequency and the severity of the extreme events. The resulting distribution is based on a threshold model and compound extreme value distribution. For frequency of events exceeding a threshold of 150,000, we found that it follows a negative binomial distribution, while severity of exceedance follows a generalized Pareto distribution. This distribution fits the data well and is found to be a better model for natural disasters in Kenya than the traditional extreme value threshold model.

It is a well-known result in operator theory that whenever two operators are similar then they have equal spectra even though they do not have to belong to the same class of operators. However under a stronger relation of unitary equivalence it can be shown that two unitarily equivalent operators may belong to the same class of operators. In this paper we endeavor to exhibit results on such classes of operators which belong to same class under unitary equivalence.

Itis a known fact in operator theory that two similar operators have equal spectra but they do not necessarily have to belong to the same class of operators. However,under the stronger relation of unitary equivalence it can be shown that two unitarily equivalent operators may belong to the same class of operators. In this paper we endeavor to exhibit some results on some pairs of operators which may belong to the same class under not only unitary equivalence but also isometric and co-isometric equivalence

In this paper we investigate unitary quasi-equivalence of operators in Hilbert spaces. We characterize operators that are unitarily quasi-equivalent. We also investigate equivalence relations closely related to unitary quasi-equivalence. We give and prove conditions under which unitary quasi-equivalence coincides with other operator equivalence relations.

In this paper we investigate unitary quasi-equivalence of operators in Hilbert spaces. We characterize operators that are
unitarily quasi-equivalent. We also investigate equivalence relations closely related to unitary quasi-equivalence. We give
and prove conditions under which unitary quasi-equivalence coincides with other operator equivalence relations

Dengue fever (DF) is an arboviral disease caused by dengue virus serotypes 1-4 (DENV 1-4). Globally, DF incidence and disease burden have increased in the recent past. Initially implicated in a 1982 outbreak, DENV-2 recently reemerged in Kenya causing outbreaks between 2011 and 2014 and more recently 2017-8. The origin and the evolutionary patterns that may explain the epidemiological expansion and increasing impact of DENV-2 in Kenya remain poorly understood. Using whole-genome sequencing, samples collected during the 2011-4 and 2017-8 dengue outbreaks were analyzed. Additional DENV-2 genomes were downloaded and pooled together with the fourteen genomes generated in this study. Bioinformatic methods were used to analyze phylogenetic relationships and evolutionary patterns of DENV-2 causing outbreaks in Kenya. The findings from this study have shown the first evidence of circulation of two different Cosmopolitan genotype lineages of DENV-2; Cosmopolitan-I (C-I) and Cosmopolitan-II (C-II), in Kenya. Our results put the origin location of C-I lineage in India in 2011, and C-II lineage in Burkina Faso between 1979 and 2013. C-I lineage was the most isolated during recent outbreaks, thus showing the contribution of this newly emerged strain to the increased DENV epidemics in the region. Our findings, backed by evidence of recent local epidemics that have been associated with C-I in Kenya and C-II in Burkina Faso, add to the growing evidence of expanding circulation and the impact of multiple strains of DENV in the region as well as globally. Thus, continued surveillance efforts on DENV activity and its evolutionary trends in the region, would contribute toward effective control and the current vaccine development efforts.

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ABSTRACT
Introduction: Treatment of microbial infections has become complicated
due to increased resistance of microbes to the current drugs. The current
study investigates crude extracts and seven compounds from root and
stem bark of Cordia africana Lam. for antimicrobial and cytotoxic activity.
Methods: Extraction was done using 50% methanol in dichloromethane,
followed by chromatographic separation of compounds, whose structures
were established by interpretation of spectroscopic data. The in vitro
susceptibility of selected microbes to the crude extracts and pure compounds was determined. Cytotoxicity of 1, 6 and 7 was determined against
the drug sensitive, CCRF-CEM and resistant CEM/ADR-5000 cells, with
doxorubicin used as the standard. Results: The root bark extract of
C. africana yielded six known compounds: oleanolic acid (1), 3-β-lup-20(29)-
en-3-ol (2) stigmast-5,22-dien-3β-ol (3), 2-(2Z) -(3-hydroxy-3,7-dimethylocta2,6-dienyl)-1,4-benzenediol (4), 4-hydroxy-3-methoxy- benzaldehyde (5)
and 7-hydroxy-4′-methoxyisoflavone (6). The stem bark extract resulted to
1 and 2 alongside, ubiquinone-8 (7) and 1-octacosanol (8). Compound 1
showed moderate activity against Enterococcus faecium (IC50 of 14.44 µg/
mL), with vancomycin being inactive. Compounds 1, 6 and 7 showed cell
viability >50% against CEM/ADR5000 and CCRF-CEM cells at 10 µM and
therefore were considered inactive. Surprisingly, 1 was relatively more active compared to the standard, with cell viability of 57.93% against CEM/
ADR5000, versus 78.97% for doxorubicin. Conclusion: To the best of our
knowledge, this is the first report of the eight compounds from C. africana.
The cytotoxicity of 1, 6 and 7 are reported here for the first time. Traditional
use of the plant extract in management of various infections may be attributed to presence of 1, which displayed moderate antimicrobial activity.
Key words: Cordia africana, Ubiquinone-8, Oleanolic acid acid, 7-hydroxy4′-methoxyisoflavone, VRE.
Correspondence:
Rahab W. Kamau
Department of Chemistry, Masinde Muliro University of Science and Technology, P.O. Box 190-50100-Kakamega, KENYA.

In this paper, we consider generalised distributions in the context of modelling dispersion but with focus on probability generating function (pgf) which is an important tool in studying statistical properties of a discrete distribution. The aim of this paper is twofold, one is to demonstrate the power of generalising in determination of pgf and two is to show that relationship between power series can naturally lead to pgf of a generalised distribution. Generalised Poisson distributions such as negative binomial, Pólya-Aeppli and Neyman type A are used to model overdispersed (clustered) populations and they all have Poisson as a limiting distribution as contagion breaks down to randomness. In particular, the Pólya-Aeppli distribution served as a typical example in underpinning the inherent power of generalising in determining the pgf. Based on the power series distributions, it is affirmed that negative binomial distribution is a generalised Poisson distribution by utilising the relationship between exponential,

A search for a distribution which adequately describes the dynamics of log returns has been a subject of study for many years. Empirical evidence has resulted in stylized facts of returns. Arguably, in this study, the three components of returns, mean equation part, the changing variance. part and the resulting residuals are determined and their corresponding parameters estimated within the proposed framework. Spectral density analysis is used to trace the seasonality component.
inherent in the standardized residuals. Empirical data sets from eight different indexes and common
stock are applied to the model, and results tabulated in support of the resulting framework.

In this paper, we show how to find dual frames using the notion of singular value decomposition and pseudo-inverses of an operator in a Hilbert space. We will also show how properties of dual frames are linked to the spectral properties of the dual frame operator and the Grammian

Wireless sensor networks (WSNs) form a large part of the ecosystem of the Internet of Things (IoT), hence they have numerous application domains with varying performance and availability requirements. Limited resources that include processing capability, queue capacity, and available energy in addition to frequent node and link failures degrade the performance and availability of these networks. In an attempt to efficiently utilise the limited resources and to maintain the reliable network with efficient data transmission; it is common to select a clustering approach, where a cluster head is selected among the diverse IoT devices. This study presents the stochastic performance as well as the energy evaluation model for WSNs that have both node and link failures. The model developed considers an integrated performance and availability approach. Various duty cycling schemes within the medium-access control of the WSNs are also considered to incorporate the impact of sleeping/idle states that are presented using analytical modeling. The results presented using the proposed analytical models show the effects of factors such as failures, various queue capacities and system scalability. The analytical results presented are in very good agreement with simulation results and also present an important fact that the proposed models are very useful for identification of thresholds between WSN system characteristics.

The sub-surface is used in most parts of Africa as a repository of human waste and as a source of groundwater through pit latrines and shallow wells respectively. The wells provide freshwater to millions of people in Africa who are either not connected to the piped water or have intermittent supplies. These shallow wells are hand dug and therefore are mostly less than 20 meters in depth. This same sub-surface environment is also used as a repository of human waste through pit latrines. The water points and the sanitation facilities are mostly located close to each other. This study aimed at appraising the groundwater and sanitation challenges based on a rapid survey, sampling, interviews, existing literature review and historical borehole data in Kisumu city, Kenya. Previous studies in the area have shown that the number of shallow wells, city buildings, density of unimproved pit latrines and sanitary risks have increased tremendously between 1999 and 2019. Most of the wells are shallow and therefore prone to contamination by pollutants. Fluoride and chloride content in most boreholes are above the recommended WHO maximum values and the local KEBS standards. The study confirmed that the main water and sanitation challenges in Kisumu are poor and deteriorating water quality, poor waste disposal management systems and poor sanitation services. There is need for the introduction of new and sustainable groundwater approaches supported by scientific models and involving all stakeholders. Current deficiencies in the provision of adequate water and dignified sanitation to the poor in Kisumu can be remedied through improved knowledge on shallow aquifer dynamics and innovative research. It was noted that apart from the donor agencies and multi-national NGOs, the private investors are unwilling to invest in water projects in Kisumu due in part to government legislation that constrains the cost that may be levied on water

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The sub-surface is used in most parts of Africa as a repository of human waste and as a source of groundwater through pit latrines and shallow wells respectively. The wells provide freshwater to millions of people in Africa who are either not connected to the piped water or have intermittent supplies. These shallow wells are hand dug and therefore are mostly less than 20 meters in depth. This same sub-surface environment is also used as a repository of human waste through pit latrines. The water points and the sanitation facilities are mostly located close to each other. This study aimed at appraising the groundwater and sanitation challenges based on a rapid survey, sampling, interviews, existing literature review and historical borehole data in Kisumu city, Kenya. Previous studies in the area have shown that the number of shallow wells, city buildings, density of unimproved pit latrines and sanitary risks have increased tremendously between 1999 and 2019. Most of the wells are shallow and therefore prone to contamination by pollutants. Fluoride and chloride content in most boreholes are above the recommended WHO maximum values and the local KEBS standards. The study confirmed that the main water and sanitation challenges in Kisumu are poor and deteriorating water quality, poor waste disposal management systems and poor sanitation services. There is need for the introduction of new and sustainable groundwater approaches supported by scientific models and involving all stakeholders. Current deficiencies in the provision of adequate water and dignified sanitation to the poor in Kisumu can be remedied through improved knowledge on shallow aquifer dynamics and innovative research. It was noted that apart from the donor agencies and multi-national NGOs, the private investors are unwilling to invest in water projects in Kisumu due in part to government legislation that constrains the cost that may be levied on water

The sub-surface is used in most parts of Africa as a repository of human waste and as a source of groundwater through pit latrines and shallow wells respectively. The wells provide freshwater to millions of people in Africa who are either not connected to the piped water or have intermittent supplies. These shallow wells are hand dug and therefore are mostly less than 20 meters in depth. This same sub-surface environment is also used as a repository of human waste through pit latrines. The water points and the sanitation facilities are mostly located close to each other. This study aimed at appraising the groundwater and sanitation challenges based on a rapid survey, sampling, interviews, existing literature review and historical borehole data in Kisumu city, Kenya. Previous studies in the area have shown that the number of shallow wells, city buildings, density of unimproved pit latrines and sanitary risks have increased tremendously between 1999 and 2019. Most of the wells are shallow and therefore prone to contamination by pollutants. Fluoride and chloride content in most boreholes are above the recommended WHO maximum values and the local KEBS standards. The study confirmed that the main water and sanitation challenges in Kisumu are poor and deteriorating water quality, poor waste disposal management systems and poor sanitation services. There is need for the introduction of new and sustainable groundwater approaches supported by scientific models and involving all stakeholders. Current deficiencies in the provision of adequate water and dignified sanitation to the poor in Kisumu can be remedied through improved knowledge on shallow aquifer dynamics and innovative research. It was noted that apart from the donor agencies and multi-national NGOs, the private investors are unwilling to invest in water projects in Kisumu due in part to government legislation that constrains the cost that may be levied on water

Samples of water, sediments and aquatic weeds were collected from 26 sites in the Nyando River catchment of the Lake Victoria basin in 2005–2006. The objective was to investigate levels of organochlorine pesticides that have either been banned or are restricted for use in Kenya. The pesticides investigated were lindane, aldrin, endosulfan, endrin, dieldrin, DDT, heptachlor and methoxychlor. These pesticides had previously found wide applications in public health and agriculture in Kenya for control of disease vectors and crop pests respectively. Results showed that mean concentrations were highest for methoxychlor (8.817 ± 0.020 µg l−1) in water, sediments (92.893 ± 3.039 µg kg−1), and weeds (39.641 ± 3.045 µg kg−1), the weeds also tended to accumulate aldrin (15.519 ± 3.756 µg kg−1). The results show that the pesticides are still in use and are detected in the catchment. Stringent management and public awareness measures are required to enforce the ban on the organochlorine pesticides in order to safeguard the environment and ecosystems of Lake Victoria.

Description
Samples of water, sediments and aquatic weeds were collected from 26 sites in the Nyando River catchment of the Lake Victoria basin in 2005–2006. The objective was to investigate levels of organochlorine pesticides that have either been banned or are restricted for use in Kenya. The pesticides investigated were lindane, aldrin, endosulfan, endrin, dieldrin, DDT, heptachlor and methoxychlor. These pesticides had previously found wide applications in public health and agriculture in Kenya for control of disease vectors and crop pests respectively. Results showed that mean concentrations were highest for methoxychlor (8.817 ± 0.020 µg l−1) in water, sediments (92.893 ± 3.039 µg kg−1), and weeds (39.641 ± 3.045 µg kg−1), the weeds also tended to accumulate aldrin (15.519 ± 3.756 µg kg−1). The results show that the pesticides are still in use and are detected in the catchment. Stringent management and …

Background
A prolonged and complicated second stage of labour is associated with serious perinatal complications. The Odon device is an innovation intended to perform instrumental vaginal delivery presently under development. We present an evaluation of the feasibility and safety of delivery with early prototypes of this device from an early terminated clinical study.

Methods
Hospital-based, multi-phased, open-label, pilot clinical study with no control group in tertiary hospitals in Argentina and South Africa. Multiparous and nulliparous women, with uncomplicated singleton pregnancies, were enrolled during the third trimester of pregnancy. Delivery with Odon device was attempted under non-emergency conditions during the second stage of labour. The feasibility outcome was delivery with the Odon device defined as successful expulsion of the fetal head after one-time application of the device.

Results
Of the 49 women enrolled, the Odon device was inserted successfully in 46 (93%), and successful Odon device delivery as defined above was achieved in 35 (71%) women. Vaginal, first and second degree perineal tears occurred in 29 (59%) women. Four women had cervical tears. No third or fourth degree perineal tears were observed. All neonates were born alive and vigorous. No adverse maternal or infant outcomes were observed at 6-weeks follow-up for all dyads, and at 1 year for the first 30 dyads.

Conclusions
Delivery using the Odon device is feasible. Observed genital tears could be due to the device or the process of delivery and assessment bias. Evaluating the effectiveness and safety of the further developed prototype of the BD Odon Device™ will require a randomized-controlled trial.

In this research paper we introduce the operators associated with a frame. That is the Analysis and the Synthesis Operators and their basic properties. The structure of matrix representation of the Synthesis operator is also analysed. This matrix is what most frame constructions in fact focus on. The frame operator which is just the joining together of the analysis and synthesis operators is fundamental for the reconstruction of signals form frame coefficients. We also give a complete characterization of the synthesis matrix in terms of the frame operator.

In this research paper we do an introduction to Hilbert space frames. We also discuss various frames in the Hilbert space. A frame is a generalization of a basis. It is useful, for example, in signal processing. It also allows us to expand Hilbert space vectors in terms of a set of other vectors that satisfy a certain condition. This condition guarantees that any vector in the Hilbert space can be reconstructed in a numerically stable way from its frame coe? cients. Our focus will be on frames in? nite dimensional spaces.

In this paper, nonparametric regression is employed which provides an estimation of unknown finite population
totals. A robust estimator of finite population totals in model based inference is constructed using the procedure of local linear
regression. In particular, robustness properties of the proposed estimator are derived and a brief comparison between the
performances of the derived estimator and some existing estimators is made in terms of bias, MSE and relative efficiency.
Results indicate that the local linear regression estimator is more efficient and performing better than the Horvitz-Thompson
and Dorfman estimators, regardless of whether the model is specified or mispecified. The local linear regression estimator also
outperforms the linear regression estimator in all the populations except when the population is linear. The confidence
intervals generated by the model based local linear regression method are much tighter than those generated by the design
based Horvitz-Thompson method. Generally the model based approach outperforms the design based approach regardless of
whether the underlying model is correctly specified or not but that effect decreases as the model variance increases.
Keywords: Nonparametric Regression, Finite Population Totals, Local Linear Regression, Robustness Properties,
Confidence Intervals, Model Based Surveys

Internet is the prototype of the global information infrastructure. Firms are using the Internet primarily for sales and service by advertising and providing customers with relevant information about a product or service. This paper describes the emerging implications of Internet technology as an evolving medium that offers restaurants limitless opportunities for e-commerce and for creating lasting relationships with customers. It dampens the bargaining power of channels by providing companies with new and more direct avenues to customers .The Internet provides an efficient means to order products. Online ordering being one of the e-commerce initiatives has emerged as an alternative avenue for food outlets to grow their sales. It offers more opportunities for interactive and personalised marketing as well as ease, speed and precision for the consumer. Food-outlets are able to offer the service through their own websites, multi-restaurant sites, mobile applications, and text ordering. Studies have shown that online food ordering can result in an increase in revenue, average check value, volume of sales, frequency of sales, order accuracy, productivity, improved convenience and customer relationship management. On line food ordering is new in Kenya. Few studies have been done in Kenya to determine the extent and distribution of online ordering by food outlets, and preference for distribution channels. From a population of 408 middle to upscale food outlets in Nairobi, this study sought answers to these questions. The results show that 23.7% of the outlets currently offer online ordering. The offerings were found to be independent of the restaurant type, but dependent on the type of cuisine offered. The characterization provided by this study lays the ground work for future work on the impact adoption has had on business performance.

Description
The study aimed at optimizing the extraction conditions and establishing the physicochemical properties of the mucilage obtained from root bark of Malva verticillata. Effects of temperature, time, particle size and amount of water as a solvent on the yield and composition of mucilage were established. Micrometric, physical, chemical and structural properties were used to characterise the extracted mucilage. Result showed significant correlation between extraction conditions and mucilage yield. Low temperature and short extraction time results into pharmaceutically valuable mucilage with low protein content, high viscosity and good dispersion in aqueous solvent. Large and small size particles of the plant material results into low mucilage yield without significant difference (p= 0.054). The mucilage shows mixed cohesiveness with less tendencies to flow. It exhibits vibration bands in FTIR that are associated with the presence of polysaccharides and proteins. The mucilage contains 2.65% protein, 13.83% inorganics, 1.85% fats, and the rest carbohydrates. High extractive value˃ 80% and moisture content˃ 12% implies that mucilage has high tendency to microbial attack. Optimized extraction conditions results into high yield of the mucilage with the same physicochemical properties and mineral composition regardless of the plant material sampling sites.

Description
Production and use of most organochlorine pesticides (OCPs) was banned through the Stockholm Convention on persistent organic pollutants. However, appreciable amounts are still detected in the environment due to their persistence, illegal use, and releases from contaminated soils and obsolete stocks. The present study investigated the levels of OCP residues in Nairobi River. Sediment and water samples were collected from three sites along the river and screened for 17 OCPs using gas chromatography electron capture detector (GC-ECD). Mean pesticide residues ranged from 0.01 to 41.9 μg kg−1 in sediment and below detection limit to 39.7 ng L−1 in water. In sediment α-HCH, β-HCH, γ-HCH, heptachlor epoxide, and p,p′-DDD were detected in all samples, while α-HCH, γ-HCH, δ-HCH, heptachlor epoxide, endosulfan I, and endrin were detected in all water samples. Levels of OCPs in water …

Production and use of most organochlorine pesticides (OCPs) was banned through the Stockholm Convention on persistent organic pollutants. However, appreciable amounts are still detected in the environment due to their persistence, illegal use, and releases from contaminated soils and obsolete stocks. The present study investigated the levels of OCP residues in Nairobi River. Sediment and water samples were collected from three sites along the river and screened for 17 OCPs using gas chromatography electron capture detector (GC-ECD). Mean pesticide residues ranged from 0.01 to 41.9 μg kg−1 in sediment and below detection limit to 39.7 ng L−1 in water. In sediment α-HCH, β-HCH, γ-HCH, heptachlor epoxide, and p,p′-DDD were detected in all samples, while α-HCH, γ-HCH, δ-HCH, heptachlor epoxide, endosulfan I, and endrin were detected in all water samples. Levels of OCPs in water were below the WHO maximum allowable limits for surface water. However, values higher than the sediment quality guidelines for sediment samples in Racecourse Road Bridge and Outering Road Bridge were reported, thus confirming the toxicity to aquatic organisms. Consequently, as these compounds are known to bio-accumulate in fatty tissues, continued use of the river water poses a health risk to animals and humans.

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Aim: The aim of this study was to determine the treatments and their outcomes in horses with colic in Nairobi County, Kenya.
Materials and Methods: This is a retrospective study to determine the occurrence, treatments, pain management, and outcomes of colic in horses in Nairobi County. Association between pain management protocols and the outcomes of colic with regard to recovery or death was also determined. Data collected from four equine practitioners were organized manually and given numerical codes as appropriate to facilitate entry into the computer. The coded data were entered into Microsoft Excel 2010 and exported to StatPlus pro 5.9. 8 statistical package for analysis. Simple association tests were done between various factors and occurrence of colic.
Results: The incidence of colic for the 11 years was 3.1%, which constituted 68.0% spasmodic colic, 27.8% impaction colic, and 4.2% displacement …

This article develops, a lattice-based approach for pricing contingent claims when parameters governing the logs of the underlying asset dynamics are modelled by generalized hyperbolic distribution and normal inverse Gaussian distribution. The pentanomial lattice is constructed using a moment matching procedure. Moment generating functions of generalized hyperbolic distribution and normal inverse Gaussian distribution are utilized to compute probabilities and jump parameters under historical measure P. Minimal entropy martingale measure (MEMM) is used to value European call option with a view of comparing the results with some of the existing benchmark models such as Black Scholes model. Empirical data from S&P500 index, RUTSELL2000 index and RUI1000 index are used to demonstrate how the model works. There is a significant difference especially for long term maturity (six months and above) type of contracts, the proposed model outperform the benchmark model, while performing poorly at short term contracts. Pentanomial NIG models seem to outperform the other models, especially for long-dated maturities.

Let X={P1,..., Ps}⊆ Pn, with s≥ n+ 1, be a set of points in general position, and S be the sub-scheme supported at these points. The minimal resolution conjecture asserts that the homogeneous ideal of this sub-scheme, IS⊂ R= k [x0,..., xn], where k is an algebraically closed field and R the homogeneous coordinate ring of Pn, has the following expected form;

Thestudy investigates the organochlorine pesticides residue level in air and soilat sites in Nairobi and Mount Kenya regions, Kenya. Air and soil samples from four sites were collected and analysed for selected organochlorine pesticides (OCP) using gas chromatography equipped with electron capture detector and confirmed using GC/MS. The targeted pesticides were α-HCH, β-HCH, γ-HCH (lindane), α- endosulfan, β-endosulfan and Endosulfansulfate. The samples were collected seasonally between the monthsof July 2012 and April 2013. The residue levels of organochlorine pesticides in air samples during month of October ranged between0.027±0.004 to5.735±0.575 ng/M3, while during the Month of February the concentration ranged between 0.013±0.00 to 9.375±1.65 ng/M3 and the levels during the month of April ranged between 0.013±0.00 to 11.508±0.26ng/M3. Organochlorine pesticide detected in soil during month of October ranged between BDL to 131.206 ± 14.41ng/Kg, while during the Month of February the concentration ranged between 0.418± 0.01to 38.361 ±5.39 ng/Kg and the levels during the month of April ranged between 0.406± 0.00to 26.877± 8.89 ng/Kg. The residue levels of the analysedPOPs in air and soil were generally high at the Dandora and Industrial area sites. This indicates that industrial activities such as Tetra-Pac, general plastics, Phillips industries waste and stock piles are the main sources of the new POPs in Nairobi. The high concentration level poses a health risk to residents of Dandora and Industrial area workers.

Keywords: Dandora, Kabete, Industrial area, Mount Kenya, organochlorine pesticide residues, air, soil

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The pay-as-you-go pricing model and the illusion of unlimited resources in the Cloud initiate the idea to provision services elastically. Elastic provisioning of services allocates/de-allocates resources dynamically in response to the changes of the workload. It minimizes the service provisioning cost while maintaining the desired service level objectives (SLOs). Model-predictive control is often used in building such elasticity controllers that dynamically provision resources. However, they need to be trained, either online or offline, before making accurate scaling decisions. The training process involves tedious and significant amount of work as well as some expertise, especially when the model has many dimensions and the training granularity is fine, which is proved to be essential in order to build an accurate elasticity controller. In this paper, we present OnlineElastMan, which is a self-trained proactive elasticity manager for cloud-based storage services. It automatically evolves itself while serving the workload. Experiments using OnlineElastMan with Cassandra indicate that OnlineElastMan continuously improves its provision accuracy, i.e., minimizing provisioning cost and SLO violations, under various workload patterns.

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Fusarium head blight (FHB) is an important disease of small grain cereals. This study
assessed the incidence and severity of FHB of wheat at hard dough stage, and levels of
deoxynivalenol and T2-toxin at harvest by direct competitive enzyme linked immuno-sorbent
assay. Wheat ears were randomly sampled from 51 farms in Narok County and 51 farms in
Nakuru County at hard dough stage while wheat kernels were sampled at harvest.
Prevalence of FHB in both Counties was 100%. The mean incidence of FHB was 28.4 …