Performance of Magnetostrictive Amorphous Wire Sensor in Motor Speed Measurement

This paper presents the performance analysis of magnetostrictive amorphous wire in motor speed measurement. The principle of the operation of the sensor is based on Large Barkhausen Jump (LBJ), a unique feature of the wire. A dc motor is used due to the linear relationship between applied voltage and speed. The supply voltage of the dc motor is varied and motor speed measured. The frequency of the signal obtained from the magnetostrictive amorphous wire sensor is measured using an oscilloscope and the motor speed calculated from this frequency. Results obtained from amorphous wire sensor show quite good agreement with that of the digital tachometer. Keywords:  Large Barkhausen Jump (LBJ), Magnetostrictive Amorphous Wire, Speed senso

Effect of Length and Position Relative to the Rotor of the Magnetostrictive Amorphous Wire in Motor Speed Sensing

The performance of the magnetostrictive amorphous wire in motor speed sensing has been shown to match that of conventional motor speed sensors. The sensor is based on Large Barkhausen Jump, a unique feature of the wire, which occurs at a given critical length of the wire. A permanent magnet is also used and therefore depending on the strength of the magnet used, the position of the sensor relative to the rotor is expected to influence the results. This paper presents experimental results on the influence of length and position of the magnetostrictive amorphous wire on the performance of the sensor. A close observation on the signal waveforms indicate that there is a critical length and optimal positioning of the wire from the magnet for which the performance of the sensor is satisfactory Keywords:  Length, Magnetostrictive Amorphous Wire, Position, Speed sensin

Preferred resting surfaces of dominant malaria vectors inside different house types in rural south-eastern Tanzania

Background: Malaria control in Africa relies extensively on indoor residual spraying (IRS) and insecticide-treated nets (ITNs). IRS typically targets mosquitoes resting on walls, and in few cases, roofs and ceilings, using contact insecticides. Unfortunately, little attention is paid to where malaria vectors actually rest indoors, and how such knowledge could be used to improve IRS. This study investigated preferred resting surfaces of two major malaria vectors, Anopheles funestus and Anopheles arabiensis, inside four common house types in rural south-eastern Tanzania. Methods: The assessment was done inside 80 houses including: 20 with thatched roofs and mud walls, 20 with thatched roofs and un-plastered brick walls, 20 with metal roofs and un-plastered brick walls, and 20 with metal roofs and plastered brick walls, across four villages. In each house, resting mosquitoes were sampled in mornings (6 a.m.–8 a.m.), evenings (6 p.m.–8 p.m.) and at night (11 p.m.–12.00 a.m.) using Prokopack aspirators from multiple surfaces (walls, undersides of roofs, floors, furniture, utensils, clothing, curtains and bed nets). Results: Overall, only 26% of An. funestus and 18% of An. arabiensis were found on walls. In grass-thatched houses, 33–55% of An. funestus and 43–50% of An. arabiensis rested under roofs, while in metal-roofed houses, only 16–20% of An. funestus and 8–30% of An. arabiensis rested under roofs. Considering all data together, approximately 40% of mosquitoes rested on surfaces not typically targeted by IRS, i.e. floors, furniture, utensils, clothing and bed nets. These proportions were particularly high in metal-roofed houses (47–53% of An. funestus; 60–66% of An. arabiensis). Conclusion: While IRS typically uses contact insecticides to target adult mosquitoes on walls, and occasionally roofs and ceilings, significant proportions of vectors rest on surfaces not usually sprayed. This gap exceeds one-third of malaria mosquitoes in grass-thatched houses, and can reach two-thirds in metal-roofed houses. Where field operations exclude roofs during IRS, the gaps can be much greater. In conclusion, there is need for locally-obtained data on mosquito resting behaviours and how these influence the overall impact and costs of IRS. This study also emphasizes the need for alternative approaches, e.g. house screening, which broadly tackle mosquitoes beyond areas reachable by IRS and ITNs

Plasmodium falciparum parasitaemia and clinical malaria among school children living in a high transmission setting in western Kenya.

BACKGROUND: Malaria among school children is increasingly receiving attention, yet the burden of malaria in this age group is poorly defined. This study presents data on malaria morbidity among school children in Bungoma county, western Kenya. METHOD: This study investigated the burden and risk factors of Plasmodium falciparum infection, clinical malaria, and anaemia among 2346 school children aged 5-15 years, who were enrolled in an individually randomized trial evaluating the effect of anthelmintic treatment on the risks of malaria. At baseline, children were assessed for anaemia and nutritional status and information on household characteristics was collected. Children were followed-up for 13 months to assess the incidence of clinical malaria by active detection, and P. falciparum infection and density evaluated using repeated cross-sectional surveys over 15 months. RESULTS: On average prevalence of P. falciparum infection was 42% and ranged between 32 and 48% during the five cross-sectional surveys. Plasmodium falciparum prevalence was significantly higher among boys than girls. The overall incidence of clinical malaria was 0.26 episodes per person year (95% confidence interval, 0.24-0.29) and was significantly higher among girls (0.23 versus 0.31, episodes per person years). Both infection prevalence and clinical disease varied by season. In multivariable analysis, P. falciparum infection was associated with being male, lower socioeconomic status and stunting. The risk of clinical malaria was associated with being female. CONCLUSION: These findings show that the burden of P. falciparum parasitaemia, clinical malaria and anaemia among school children is not insignificant, and suggest that malaria control programmes should be expanded to include this age group

Sociocultural factors influencing breastfeeding practices in two slums in Nairobi, Kenya

Background: Despite numerous interventions promoting optimal breastfeeding practices in Kenya, pockets of suboptimal breastfeeding practices are documented in Kenya’s urban slums. This paper describes cultural and social beliefs and practices that influence breastfeeding in two urban slums in Nairobi, Kenya. Methods: Qualitative data were collected in Korogocho and Viwandani slums through 10 focus group discussions and 19 in-depth interviews with pregnant, breastfeeding women and community health volunteers and 11 key-informant interviews with community leaders. Interviews were audiotaped, transcribed verbatim, coded in NVIVO and analyzed thematically. Results: Social and cultural beliefs and practices that result to suboptimal breastfeeding practices were highlighted including; considering colostrum as ‘dirty’ or ‘curdled milk’, a curse ‘bad omen’ associated with breastfeeding while engaging in extra marital affairs, a fear of the ‘evil eye’ (malevolent glare which is believed to be a curse associated with witchcraft) when breastfeeding in public and breastfeeding being associated with sagging breasts. Positive social and cultural beliefs were also identified including the association of breast milk with intellectual development and good child health. The beliefs and practices were learnt mainly from spouses, close relatives and peers. Conclusion: Interventions promoting behavior change with regards to breastfeeding should focus on dispelling the beliefs and practices that result to suboptimal breastfeeding practices and to build on the positive ones, while involving spouses and other family members as they are important sources of information on breastfeeding

Effectiveness of home-based nutritional counselling and support on exclusive breastfeeding in urban poor settings in Nairobi: a cluster randomized controlled trial

Background: Exclusive breastfeeding (EBF) improves infant health and survival. We tested the effectiveness of a homebased intervention using Community Health Workers (CHWs) on EBF for six months in urban poor settings in Kenya. Methods: We conducted a cluster-randomized controlled trial in Korogocho and Viwandani slums in Nairobi. We recruited pregnant women and followed them until the infant’s first birthday. Fourteen community clusters were randomized to intervention or control arm. The intervention arm received home-based nutritional counselling during scheduled visits by CHWs trained to provide specific maternal infant and young child nutrition (MIYCN) messages and standard care. The control arm was visited by CHWs who were not trained in MIYCN and they provided standard care (which included aspects of ante-natal and post-natal care, family planning, water, sanitation and hygiene, delivery with skilled attendance, immunization and community nutrition). CHWs in both groups distributed similar information materials on MIYCN. Differences in EBF by intervention status were tested using chi square and logistic regression, employing intention-to-treat analysis. Results: A total of 1110 mother-child pairs were involved, about half in each arm. At baseline, demographic and socioeconomic factors were similar between the two arms. The rates of EBF for 6 months increased from 2% pre-intervention to 55.2% (95% CI 50.4–59.9) in the intervention group and 54.6% (95% CI 50.0–59.1) in the control group. The adjusted odds of EBF (after adjusting for baseline characteristics) were slightly higher in the intervention arm compared to the control arm but not significantly different: for 0–2 months (OR 1.27, 95% CI 0.55 to 2.96; p = 0.550); 0–4 months (OR 1.15; 95% CI 0.54 to 2.42; p = 0.696), and 0–6 months (OR 1.11, 95% CI 0.61 to 2.02; p = 0.718). Conclusions: EBF for six months significantly increased in both arms indicating potential effectiveness of using CHWs to provide home-based counselling to mothers. The lack of any difference in EBF rates in the two groups suggests potential contamination of the control arm by information reserved for the intervention arm. Nevertheless, this study indicates a great potential for use of CHWs when they are incentivized and monitored as an effective model of promotion of EBF, particularly in urban poor settings. Given the equivalence of the results in both arms, the study suggests that the basic nutritional training given to CHWs in the basic primary health care training, and/or provision of information materials may be adequate in improving EBF rates in communities. However, further investigations on this may be needed. One contribution of these findings to implementation science is the difficulty in finding an appropriate counterfactual for community-based educational interventions. Trial registration: ISRCTN ISRCTN83692672. Registered 11 November 2012. Retrospectively registered

COP27 climate change conference: Urgent action needed for Africa and the world

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Improved Land Management in the Lake Victoria Basin: Annual Technical Report, July 2000 to June 2001

ICRAF and the Kenyan Ministry of Agriculture and Rural Development (MOARD) are implementing a project on “Improved Land Management in the Lake Victoria Basin.” The project began in 1999 – 2000 with a one-year startup year of activities under the Sida-sponsored National Soil and Water Conservation Programme (NSWCP). The collaborative project of ICRAF and MOARD has now been continued for another three years under the National Agriculture and Livestock Extension Programme (NALEP). This paper summarizes achievements and findings for the project for the year 2000 / 2001. The Swedish International Development Agency (SIDA) supports “Improved Land Management in the Lake Victoria Basin” through NALEP. Additional financial support for the activities reported herein was also provided by the Rockefeller Foundation, ICRAF core funds, Danida, the University of Florida and the USAID. Research conducted during 2000 / 2001 addressed a range of issues across a large tract of Western Kenya. A coarse resolution assessment of soil erosion risk conducted for the entire Lake Victoria Basin identified the Nzoia / Yala and Kagera river basins as those with the greatest percentage of land at risk. Biophysical research on land management problem domains has quantified the widespread spatial extent of soil physical and chemical degradation in the Nyando river basin and illustrated four contrasting biophysical problem domains within the basin. District-level data on population density, poverty and agricultural production available from secondary sources have been complemented with baseline household and community survey data collected in 9 villages around the Nyando river basin. The overall picture that is emerging is that while much of the Nyando river basin has experienced some physical and chemical land degradation, there are pockets of severe poverty, severe environmental degradation and extremely low agricultural production. Different approaches to extension, investment and policy may be needed to address poverty – environment – agricultural problems in different parts of the river basin. Reversing trends in environmental deterioration will require interventions on farmers fields and in the many areas between farms that publicly-used, although usually privately-owned. Farmers have demonstrated their willingness to adopt recommended conservation practices on their individual family fields, but the intensity of adoption depends upon the potential returns to investments, their cultural grouping, and the approach that extension providers take to the provision of information and mobilization of community participation. Adoption of improved practices and investments on publicly-used areas between farms requires the mobilization of collective action among small, medium and large groups. Collective action in the Nyando River basin is most likely to be effective where it harnesses local institutional arrangements (e.g. sub-clan affiliations among the Luo) and advances common interests in the provision of high quality water and the generation of additional cash income. Among other opportunities, there appears to be good prospects for market-oriented agroforestry for production of fruit, fuelwood and timber. Changes in local and national policies would help to ensure good returns for smallholder farmers. This report begins with a presentation of a number of major findings, implications of those findings for extension and investment and implications for policy. A summary of progress by activity is then presented, followed by lists of personnel involved, presentations and publications. An annex presents detailed accomplishments by activity

Feasibility and effectiveness of the baby friendly community initiative in rural Kenya: study protocol for a randomized controlled trial

Background: Interventions promoting optimal infant and young child nutrition could prevent a fifth of under-5 deaths in countries with high mortality. Poor infant and young child feeding practices are widely documented in Kenya, with potential detrimental effects on child growth, health and survival. Effective strategies to improve these practices are needed. This study aims to pilot implementation of the Baby Friendly Community Initiative (BFCI), a global initiative aimed at promoting optimal infant and young child feeding practices, to determine its feasibility and effectiveness with regards to infant feeding practices, nutrition and health outcomes in a rural setting in Kenya. Methods: The study, employing a cluster-randomized trial design, will be conducted in rural Kenya. A total of 12 clusters, constituting community units within the government's Community Health Strategy, will be randomized, with half allocated to the intervention and the other half to the control arm. A total of 812 pregnant women and their respective children will be recruited into the study. The mother-child pairs will be followed up until the child is 6 months old. Recruitment will last approximately 1 year from January 2015, and the study will run for 3 years, from 2014 to 2016. The intervention will involve regular counseling and support of mothers by trained community health workers and health professionals on maternal, infant and young child nutrition. Regular assessment of knowledge, attitudes and practices on maternal, infant and young child nutrition will be done, coupled with assessment of nutritional status of the mother-child pairs and morbidity for the children. Statistical methods will include analysis of covariance, multinomial logistic regression and multilevel modeling. The study is funded by the NIH and USAID through the Program for Enhanced Research (PEER) Health. Discussion: Findings from the study outlined in this protocol will inform potential feasibility and effectiveness of a community-based intervention aimed at promoting optimal breastfeeding and other infant feeding practices. The intervention, if proved feasible and effective, will inform policy and practice in Kenya and similar settings, particularly regarding implementation of the baby friendly community initiative. Trial registration:ISRCTN03467700 ; Date of Registration: 24 September 201