n/a

Experiments were carried out to determine the effects of friction stir welding on microstructure and properties of recycled Aluminum 6061 alloy, whose alloy content varied from that of primary alloy. The alloy was processed at tool speed and feed ranges of 530 rev/min–1320 rev/min and 40 mm/min–100 mm/min respectively. Microstructure examination; tensile test and Vickers microhardness evaluation were carried out. Microstructure of the alloy was in four zones including: base metal, heat affected zone, thermo-mechanically affected zone and stirred zone. Average grain size of unprocessed material was 93 μm. Processing the alloy at 530 rev/min and 100 mm/min resulted in grains of average size 93 μm, 183 μm and 7 μm; in base metal, heat affected zone and stirred zone respectively. Tensile failure occurred in heat affected zone; that was exposed to high heat. The alloy hardness decreased to a minimum in heat affected zone, followed by a brief rise in thermo-mechanically affected zone, to another maximum in stirred zone. Processed zone hardness was inversely proportional to tool speed and directly proportional to feed rate. Increase in the speed and decrease in feed, increased heat which deteriorated the properties.

Abstract

Background: Endometriosis is enigmatic clinical entity which is described as the location of the endometrial tissue external of the uterine cavity. Endometriosis constitutes a serious health issue due to its high affliction of 10% of reproductive women. With limited resources in Africa, it is essential to assess whether diagnosis of endometriosis by laparoscopic visualization can be used as a substitute for histology. Objective: To correlate the diagnosis of endometriosis by laparoscopic visualization and the histological confirmation of the biopsy taken. Methods: A prospective cross sectional study with a sample size of 443 was undertaken in the diagnosis of endometriosis among Africans in Nairobi, Kenya from March 2019 to March 2021. Women undergoing laparoscopy were screened for endometriosis by visualization and a biopsy was taken for histopathology. Diagnosis of endometriosis by visualization was correlated with histological confirmed endometriosis. Results: Women with a diagnosis of endometriosis through laparoscopic visualization were found to be 77 (17.4%) and 30 (6.8%) had positive histology for endometriosis. Laparoscopic visualization diagnosis had a low positive predictive value of 39%. Conclusion: Laparoscopic visualization diagnosis had a low positive predictive value of 39% and this did not correlate with histopathologic diagnosis. It is essential to perform biopsy with histopathology for the confirmation of endometriosis.

Abstract
Objectives: Fibromyalgia is a
complex disorder which presents with
chronic widespread musculoskeletal
pain, together with other symptoms
like fatigue, sleep disturbances and
cognitive disturbance. The cause remains
unclear but it is postulated that there
are abnormalities in neurohormonal
profile and central sensitization to pain
as the main mechanism. It is known to
occur more commonly in females than
males. This study set out to look at these
differences in terms of epidemiology and
gender differences.
Data source: We conducted online and
public library searches using the English
language.
Data extraction: We reviewed several
papers and research work focusing on
epidemiology and differences in gender
presentation. The period of the search was
between the years 1990 up to 2020.
Conclusion: Fibromyalgia is a commonly
occurring rheumatologic condition.
Gender differences exist with regard to
epidemiology, clinical presentation and
health seeking behaviors. Population
based studies would be of use to establish
the prevalence in Africa. More studies
would be necessary to explain the gender
differences noted in the many aspects
of the disease including response to
treatment.
Key words: Fibromyalgia, Fibromyalgia
in women, Gender differences and impact

Objectives: Fibromyalgia is a
complex disorder which presents with
chronic widespread musculoskeletal
pain, together with other symptoms
like fatigue, sleep disturbances and
cognitive disturbance. The cause remains
unclear but it is postulated that there
are abnormalities in neurohormonal
profile and central sensitization to pain
as the main mechanism. It is known to
occur more commonly in females than
males. This study set out to look at these
differences in terms of epidemiology and
gender differences.
Data source: We conducted online and
public library searches using the English
language.
Data extraction: We reviewed several
papers and research work focusing on
epidemiology and differences in gender
presentation. The period of the search was
between the years 1990 up to 2020.
Conclusion: Fibromyalgia is a commonly
occurring rheumatologic condition.
Gender differences exist with regard to
epidemiology, clinical presentation and
health seeking behaviors. Population
based studies would be of use to establish
the prevalence in Africa. More studies
would be necessary to explain the gender
differences noted in the many aspects
of the disease including response to
treatment.
Key words: Fibromyalgia, Fibromyalgia
in women, Gender differences and impact
of fibromyalgia

Efficient management of construction works should focus its attention on utilizing labour, equipment, and raw materials in the right way. Besides, they claim that responsible parties should evaluate labour productivity continuously and that cost control measures should be developed. Low productivity witnessed in construction is linked to internal challenges including disputes, abandonment of projects, excess budget, and time overlaps. The objective of the study was to determine the financial effect of labour related risks on completion of PPP projects. A descriptive survey design was used with simple random sampling targeting 85 members of the management team at the completed Sondu-Miriu Power project. The participants were administered with questionnaire which were sent by mail (in some cases) and selected participants encouraged to respond. Data obtained was analysed through SPSS platform using descriptive statistics and Pearson Moment correlation as inferential statistics. The study found that labour related risks in construction PPP projects included failure by employees and experts to complete assigned tasks, injuries and deaths, changing labour demands during the project as well as cases of go slow. Construction labour related risks affected the financial cost, time and quality of work performed in the construction project. The study concludes that labour related risks have a financial effect on completion of PPP projects such that as the risks increase, the financial cost increases. The study recommends that more focus should be placed on the identification and recruitment of project staff as well task allocation.

This paper investigates the effect of FDI on performance of manufacturing firms in
Kenya. Little is documented about the link between FDI variables of capital flow,
advanced production technology, marketing expertise and management know-how
and performance of firms. The study’s sought to establish the effect of each
individual FDI variables on firm’s performance. It also sought to established the
overall effect of the performance manufacturing firms in Kenya. The population of
study comprised 100 companies registered with Kenya Association Manufacturing
as at the time of data collection in 2019 and that had over 10 percent foreign
ownership. The respondents were the CEOs of organization. The study used a
structured questionnaire to collect primary data. Descriptive and inferential
statistics were both used to analyze the data. Data was pretested for normality,
linearity, multicollinearity, autocorrelation and homoscedasticity and the data found
to meet most of these preconditions. The Pearson correlation analysis was employed
to discern not only the strength but also the direction of the interrelationships
involving the variables. The researcher tested the effect of the components of FDI
on performance of manufacturing firms. The study developed one hypothesis and
four sub hypothesis. The results revealed that there was a statistically significant
relationship between FDI and firm performance. This imply that to achieve better
firm performance, the government need to come up with policies geared to
attracting more FDI into the key sectors of the economy.

Gachau, S; Njeru Njagi, E; Owuor, N; Mwaniki, P; Quartagno, M; Sarguta, R; English, M; Gachau, S; Njeru Njagi, E; Owuor, N; Mwaniki, P; Quartagno, M; Sarguta, R; English, M; Ayieko, P; - view fewer (2021) Handling missing data in a composite outcome with partially observed components: Simulation study based on clustered paediatric routine data. Journal of Applied Statistics (In press) … This version is the author accepted manuscript. For information on re-use, please refer to the publisher's terms and conditions.

Gachau, S; Njeru Njagi, E; Owuor, N; Mwaniki, P; Quartagno, M; Sarguta, R; English, M; Gachau, S; Njeru Njagi, E; Owuor, N; Mwaniki, P; Quartagno, M; Sarguta, R; English, M; Ayieko, P; - view fewer (2021) Handling missing data in a composite outcome with partially observed components: Simulation study based on clustered paediatric routine data. Journal of Applied Statistics (In press) … This version is the author accepted manuscript. For information on re-use, please refer to the publisher's terms and conditions.

Gachau, S; Njeru Njagi, E; Owuor, N; Mwaniki, P; Quartagno, M; Sarguta, R; English, M; Gachau, S; Njeru Njagi, E; Owuor, N; Mwaniki, P; Quartagno, M; Sarguta, R; English, M; Ayieko, P; - view fewer (2021) Handling missing data in a composite outcome with partially observed components: Simulation study based on clustered paediatric routine data. Journal of Applied Statistics (In press) … This version is the author accepted manuscript. For information on re-use, please refer to the publisher's terms and conditions.

Emerald Publishing Limited, UK.

Leucas calostachys is widely used in traditional medicine in Kenya for management of various ailments including malaria. Bio-assay guided fractionation of Leucas calostachys extracts was carried out using in-vitro antiplasmodial and β-hematin inhibition assays with semi-preparative high performance liquid chromatography (HPLC). The active methanol fraction was subjected to liquid chromatography tandem mass spectrometry to identify constituent compounds. A total of twenty compounds consisting of eight flavonoids and 12 phenylethanoids were identified from this fraction. The flavonoids included, isorhamnetin, luteolin-7-O-glucoside, luteolin-4′-O-glucoside, luteolin diglucoside, apigenin-O-glucoside, genistein-O-glucoside, chrysoeriol-7-O-glucoside, and chrysoeriol-7-O-glucuronide. Seven of the phenylethanoids were identified as acteoside, isoactoeside, hydroxyacteoside, forthsoside B, samioside, alyssonoside and leucoseptoside A. The antimalarial activity of Leucas calostachys could be linked to presence of flavonoids and phenylethanoids.

Background: Alcohol-based hand sanitizers (ABHS) have become widely used products since the advent of the SARS-CoV-2 coronavirus based COVID-19 pandemic. In addition to ethanol or isopropanol (the active ingredients of ABHS) and water, these products are formulated with a number of ingredients to optimize delivery, efficacy and safety as well as to provide consumer appeal. Despite the widespread use of ABHS, there is very limited information in the literature on the non-alcohol ingredients used in these products.
Objectives: The aim of this work was to determine the inactive ingredients used in ABHS marketed in metropolitan Nairobi.
Methodology: ABHS products were randomly obtained from several locations at retail outlets within the Nairobi metropolitan region. The ingredients used in each ABHS were obtained from the product labels.
Results: The most common inactive ingredients based on percentage frequency of listing on product labels were glycerin (50%), fragrances (36%), carbomer (26%), triethanolamine (18%) and propylene glycol (17%). It was observed that some products incorporated additional antimicrobial agents and preservatives in the formulation. The fragrances and some of the preservatives used in the ABHS products are potential allergens. Incomplete or inadequate ingredient naming was noted for several products.
Conclusions: There is a need for ABHS manufacturers to fully disclose all raw materials used in ABHS products using standardized ingredient nomenclature. ABHS users need to be aware of potential allergens present in respective marketed products.

The influence of each entity in a network is a crucial index of the network information dissemination. Greedy influence maximization algorithms suffer from time efficiency and scalability issues. In contrast, heuristic influence maximization algorithms improve efficiency, but they cannot guarantee accurate results. Considering this, this paper proposes a Gaussian propagation model based on the social networks. Multi-dimensional space modeling is constructed by offset, motif, and degree dimensions for propagation simulation. This space’s circumstances are controlled by some influence diffusion parameters. An influence maximization algorithm is proposed under this model, and this paper uses an improved CELF algorithm to accelerate the influence maximization algorithm. Further, the paper evaluates the effectiveness of the influence maximization algorithm based on the Gaussian propagation model supported by theoretical proofs. Extensive experiments are conducted to compare the effectiveness and efficiency of a series of influence maximization algorithms. The results of the experiments demonstrate that the proposed algorithm shows significant improvement in both effectiveness and efficiency.

Universal health coverage (UHC) is an integral part of the United Nations sustainable development goals. The private sector plays a prominent role in achieving UHC, being the primary source of essential medicines for many people. However, many private healthcare facilities in low‐ and middle‐income countries (LMICs) have insu_cient stocks of essential medicines. At the same time, these same facilities carry excessive quantities of certain drugs, leading to obsolescence. This suggests poor inventory control. To propose potential remedies it is vital to fully understand the underlying causes. In semi‐structured interviews with managers of private healthcare facilities in Nairobi, we asked them about their 1) inventory control systems, 2) inventory control skills, 3) time/human resource constraints, 4) budget constraints, 5) motivations for inventory control, and 6) suppliers. Our results suggest that the problems are driven by resource limitations (budget and time/human resources), managerial issues (relating to skills and systems), and market mechanisms that limit overage and underage costs. Unavailability at the supplier level and motivations for inventory control are relatively minor issues. We posit that the key causes are interlinked and stem from wider issues in the market and regulatory environment. Our results challenge prevalent beliefs about medicine supply chains in LMICs and lead to alternative hypotheses. Testing these hypotheses could improve our understanding of inventory management in private healthcare facilities and aid progress in achieving UHC.

Natural fibers have emerged as an important component in the development of composite materials because of their mechanical properties. The properties are highly influenced by environmental conditions and processing techniques. This variability makes their usability in reinforcement unpredictable. There are satisfactory attempts to quantify the variation of the properties with environmental conditions. However, the quantification of how the properties vary with processing methods is unsatisfactory. This study, therefore, investigated and quantified the effects of processing variables on the properties of sisal fibers using a raspador. The raspador was designed, fabricated, and utilized in processing sisal fibers. Processing variables such as gap size, number of extraction and brushing elements, and drum speed were investigated. The mechanical properties were determined based on ASTM C1557 standard. High correlation coefficients were found between fiber properties and the processing variables. The brushing process, mostly ignored in many cases, improved the properties of the sisal fibers.