muhammad Rabiu - Academia.edu (original) (raw)

Papers by muhammad Rabiu

Fifth International Conference On Advances in Mechanical, Aeronautical and Production Techniques - MAPT 2016, Mar 13, 2016

Tremendous amount of heat is being lost at the turbine area of an automotive turbocharger during ... more Tremendous amount of heat is being lost at the turbine area of an automotive turbocharger during its operation. Application of ceramic thermal barrier coating to components operating under severe temperature condition such as automotive turbocharger turbine volute casing can reduce the heat lost to the environment, improve the efficiency and reliability of components and extend their service life. But high cost of installation and maintenance, complexity and spallation problem due to thermal expansion mismatch between the ceramic and the metal substrate have seriously restricted the acceptance and widespread practice of ceramic thermal barrier coating. In the present study, a solvent based slurry functionally graded thermal barrier coating technique was employed in depositing different compositions of Yttria stabilized zirconia and nickel powders on a nickel alloy substrate using a simple laboratory-scale surface coating machine. The coating compositions of 25wt% YSZ & 75wt% Ni, 60wt% YSZ & 40wt% Ni and 75wt% YSZ & 25wt% Ni were used for the deposition of the first layer, second layer and third layer of the functionally graded coating on the nickel substrate respectively. Experimental validation of heat transfer across the coating and adhesion tests were used to evaluate the suitability and integrity of the functionally graded coating produced for the intended application. The coating microstructure was also analyzed using optical microscope, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). The results have shown that, the functionally graded coating produced has the heat resistance capability of 35 0 C, 140 0 C and 250 0 C for one layer, two layer and three layer respectively. The adhesion strength of the coating improved with an increase in the number of the coating layers. There was no spallation problem observed from the coating, also no crack or deformation was observed from the results of the microstructural analysis of the functionally graded coating after the experimental heat transfer tests.

Frontiers in Plant Science

The importance of phosphorus in the regulation of plant growth function is well studied. However,... more The importance of phosphorus in the regulation of plant growth function is well studied. However, the role of the inorganic phosphate (Pi) molecule in the mitigation of abiotic stresses such as drought, salinity, heavy metal, heat, and acid stresses are poorly understood. We revisited peer-reviewed articles on plant growth characteristics that are phosphorus (P)-dependently regulated under the sufficient-P and low/no-P starvation alone or either combined with one of the mentioned stress. We found that the photosynthesis rate and stomatal conductance decreased under Pi-starved conditions. The total chlorophyll contents were increased in the P-deficient plants, owing to the lack of Pi molecules to sustain the photosynthesis functioning, particularly, the Rubisco and fructose-1,6-bisphosphatase function. The dry biomass of shoots, roots, and P concentrations were significantly reduced under Pi starvation with marketable effects in the cereal than in the legumes. To mitigate P stress, p...

PLOS ONE

This study was conducted to assess the impact of the eye care programme on cataract blindness and... more This study was conducted to assess the impact of the eye care programme on cataract blindness and cataract surgical services in Sokoto, Nigeria over a 12 year period 2005-2016. Methods Data from the 2005 population based cross-sectional study of blindness in Sokoto state was re-analysed to obtain baseline estimates of the prevalence of cataract blindness and cataract surgical coverage for persons 50 years and over in Wurno health zone. A population based survey of a representative sample of persons 50 years and over in Wurno health zone was conducted in July 2016. Data on eye health workforce, infrastructure and cataract surgical services between 2005 and 2016 were analysed from relevant documents. Results In 2005 the unadjusted prevalence of bilateral cataract blindness (<3/60) in people 50 years and over in Wurno health zone was 5.6% (95% CI: 3.1, 10.1). By 2016 this had fallen to 2.1% (95% CI 1.5%, 2.7%), with the age-sex adjusted prevalence being 1.9% (95% CI 1.3%, 2.5%). The CSC for persons with visual acuity <3/60, <6/60, <6/18 for Wurno health zone was 9.1%, 7.1% and 5.5% respectively in 2005 and this had increased to 67.3%, 62.1% and 34.7% respectively in 2016. The CSR in Sokoto state increased from 272 (1005 operations) in 2006, to 596 (2799 operations) in 2014. In the 2005 survey, couching (a procedure used by traditional practitioners to dislocate the lens into the vitreous cavity) accounted for 87.5% of all cataract interventions, compared to 45.8% in the 2016 survey participants. In 2016 18% of eyes having a cataract operation with IOL implantation had a PLOS ONE |

Community eye health / International Centre for Eye Health

Which form of cataract surgery in developing countries? This letter is in response to the letter ... more Which form of cataract surgery in developing countries? This letter is in response to the letter by John Sandford-Smith on the desirability or otherwise of intracapsular cataract extraction (ICCE) surgery in many developing countries (J Comm Eye Health 2000; 13: 62). It is indeed true that in some developing countries (like northern Nigeria) the practice of couching has increased in relation to cataract surgery, especially in rural areas. This is of course a cause for concern for eye care personnel in this part of the world. A recent study in a rural community of northern Nigeria revealed that couching of the eye is being practised 5 times more than cataract surgery. What are the factors that tend to make people have couching rather than cataract surgery? There are 3 main reasons for this attitude in most parts of northern Nigeria.

Diabetic retinopathy is becoming a dominant cause of visual impairment in many parts of the Middl... more Diabetic retinopathy is becoming a dominant cause of visual impairment in many parts of the Middle East including Jordan. As such it is necessary to develop and implement effective comprehensive diabetic retinopathy programs based on evidence in order to adequately address this scourge. This presentation will demonstrate the use of evidence in development of a comprehensive (promotive, preventive, therapeutic and rehabilitative services) diabetic retinopathy program in northern Irbid, Jordan and the implementation of the program with ongoing evidence generation ( including population based survey, patient satisfaction survey, mid term program evaluation) which dictates program review and modifications. Challenges to the implementation of the program especially the evidence based changes periodically undertaken and how they were overcome will also be presented

Cataract is the leading cause of treatable blindness worldwide. Extra-capsular cataract extractio... more Cataract is the leading cause of treatable blindness worldwide. Extra-capsular cataract extraction and intraocular lens implantation (ECCE +PC IOL) is the most rewarding technique for good visual outcome and is chieved by good preoperative biometry. Aim To determine the mean axial length, cornea power and intraocular lens power for an adult population of Northern Nigeria Methods. 800 patients with age-related cataract were operated in a cataract outreach programme at Sir Yahaya Memorial Hospital, Birnin Kebbi, northwestern Nigeria Inclusion criteria included age >30 years, age-related cataract, complete keratometry and biometry records Keratometry and A scan biometry were performed for the eyes selected for surgery. Cornea powers were measured by Bausch and Lomb model keratometer KM 6 (Appassamy Associated Ltd India) Axial length measurements were done with Echoscan US-800 V1.70 (Nidek) Posterior chamber IOL power for emmetropia was determined with SRK-2 formula using EPI Info 6 ...

Results Five hundred and seventy five eyes of 575 patients satisfied the inclusion criteria. Ther... more Results Five hundred and seventy five eyes of 575 patients satisfied the inclusion criteria. There were 298 females and 277 males. The age range was 30 to 89 years. The mean age was 54.8 years and 56.3 years for females and males respectively. The mean keratometry reading for both sexes was 43.4D with a range of 37.0 to 50.5D. The mean reading for females and males was 43.7D and 43.0D respectively. The axial length measurements for both sexes had a mean of 23.4 mm (range 20.1-26.9mm). The mean for females and males was 22.9mm and 23.5mm respectively. The mean IOL power for emmetropia for both sexes was +21.10D (range +15 to +30D). The IOL power for females and males was 21.5 and 20.7D respectively. Conclusion. This study has shown that the ‘standard’ posterior chamber IOL power for emmetropia in Northern Nigerians is +21.10D. It has also revealed that the range of IOL powers that can be used in Northern Nigerians is from +15.00 to +30.00D.

South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, 2011

To determine the prevalence and causes of visual loss in different ecological zones across Nigeri... more To determine the prevalence and causes of visual loss in different ecological zones across Nigeria. A population-based survey using multi-stage, stratified, cluster random sampling with probability proportional to size comprising a nationally representative sample of adults aged > or = 40 years from six ecological zones. Distance vision was measured using reduced logMAR charts. Clinical examination included basic eye examination for all respondents and a detailed examination including visual fields, gonioscopy and fundus photography for those who were visually impaired or blind (i.e. presenting vision < 20/40 in the better eye). A principal cause of visual loss was assigned to all respondents with presenting vision < 20/40 in the better eye. A total of 15 122 persons aged > or = 40 years were enumerated, 13 599 (89.9%) of whom were examined. The prevalence of blindness varied according to ecological zone, being highest in the Sahel region (6.6%; 95% confidence interval (...

West African journal of medicine, 2008

The Kaduna State of Nigeria Eye Care Programme (KSECP) is a state-wide community-based eye care p... more The Kaduna State of Nigeria Eye Care Programme (KSECP) is a state-wide community-based eye care programme designed in the model of the World Health Organisation global initiative for the elimination of avoidable blindness by the year 2020--Vision 2020. To provide baseline data for the monitoring and evaluation of the KSECP. The study was a cross-sectional population-based survey that covered the state. A total of 8,400 people of all ages were planned to be examined across the three health zones of the state. The study population was selected by a stratified 2-stage cluster sampling technique, in which 120 communities across the health zones were randomly selected by probability proportional to size (PPS). In each chosen community 70 people of all ages were chosen randomly. Each selected person had visual acuity tested and eyes examined. Persons with vision worse than 6/18 in any of the eyes were assessed further to identify the cause(s) of visual impairment. The prevalence of blindn...

Saudi Medical Journal, 2015

Objectives: To determine the prevalence and causes of blindness and diabetic retinopathy (DR) in ... more Objectives: To determine the prevalence and causes of blindness and diabetic retinopathy (DR) in Jazan district, Southern Saudi Arabia. Methods: Using the standardized Rapid Assessment for Avoidable Blindness (RAAB) and DR cross-sectional methodology, 3800 subjects were randomly selected from the population of ≥50 years of age in Jazan, Saudi Arabia between November 2011 and January 2012. Participants underwent screening comprised of interview, random blood glucose test, and ophthalmic assessment including visual acuity (VA) and fundus examination. Among participants with VA <6/18 in either eye, the cause(s) of visual impairment was determined. Participants were classified as diabetic if they had previous diagnoses of diabetes, or random blood glucose >200 mg/dl. Diabetic participants were assessed for DR using dilated fundus examination. All data were recorded using the RAAB + DR standardized forms. Results: The prevalence of bilateral blindness <3/60 was 3.3% (95% confidence interval [CI]: 2.74-3.90). Cataract was the leading cause of blindness (58.6%); followed by posterior segment diseases (20%), which included DR (7; 3.3%). The prevalence of diabetes mellitus (DM) was 22.4%, (95% CI: 21.09-23.79), among them; 27.8% had DR. The prevalence of sightthreatening DR was 5.7%. Conclusion: The prevalence of DM and the corresponding proportion of DR in this region is lower than that reported in other regions of Saudi Arabia. However, the prevalence of blindness not related to DR is relatively higher than the other studies.

Nigerian journal of medicine : journal of the National Association of Resident Doctors of Nigeria

Childhood blindness is second only to cataract in magnitude of world blindness when the "bli... more Childhood blindness is second only to cataract in magnitude of world blindness when the "blind years" is considered. The "blind years" is the number of years a person lives with blindness. Studies have shown that over 34%-69% of childhood blindness in Nigeria is caused by corneal opacity, which results mainly from an interplay of vitamin A deficiency, measles and harmful traditional eye practices. However, vitamin A deficiency which manifests in the eye as xerophthalmia is the dominant problem in these children. The purpose of this review is to stress the importance of xerophthalmia, which is of public health significance, as an important cause of childhood blindness in Nigeria. Studies involving surveys of xerophthalmia, childhood and nutritional blindness are reviewed with data extracted from a nationwide survey on prevalence of xerophthalmia. The likely explanation for vitamin A deficiency in Nigerian children is discussed with possible solutions and recommend...

European Journal of Ophthalmology, 2015

Purpose To estimate the prevalence of blindness, visual impairment, diabetes, and diabetic retino... more Purpose To estimate the prevalence of blindness, visual impairment, diabetes, and diabetic retinopathy in north Jordan (Irbid) using the rapid assessment of avoidable blindness and diabetic retinopathy methodology. Methods A multistage cluster random sampling technique was used to select participants for this survey. A total of 108 clusters were selected using probability proportional to size method while subjects within the clusters were selected using compact segment method. Survey teams moved from house to house in selected segments examining residents 50 years and older until 35 participants were recruited. All eligible people underwent a standardized examination protocol, which included ophthalmic examination and random blood sugar test using digital glucometers (Accu-Chek) in their homes. Diabetic retinopathy among diabetic patients was assessed through dilated fundus examination. Results A total of 3638 out of the 3780 eligible participants were examined. Age- and sex-adjuste...

Tropical Medicine & International Health, 2015

To assess knowledge and practice of primary eye care among primary healthcare workers known as co... more To assess knowledge and practice of primary eye care among primary healthcare workers known as community health extension workers in Funtua district of Nigeria. Cross-sectional mixed method study among health workers employed in government-owned primary healthcare facilities. Quantitative data were obtained using self-administered questionnaires and checklists, while qualitative data by modified Delphi technique, role plays and observation. A score of 1 was given for each correct answer, while a total score of ≥60% was considered &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;good&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;. Eighty three of 88 health workers participated (94%) in the questionnaire survey; while 16 of them were selected for the qualitative survey. Good scores regarding the knowledge of common eye diseases were obtained by 68.7%, but only 26.4% of them could identify their most important features. Participants could undertake 3 of 5 steps in visual acuity testing. Skills in recognising common eye diseases and their management were weak; while practice was often not according to the guidelines. Community health extension workers displayed good knowledge of common eye diseases. Areas of weakness are recognition and interpretation of eye signs, and practice rarely follows the guidelines. Preventive medicine was neglected; community health extension workers require practical retraining and supervision to achieve integration of primary eye care into primary healthcare services.

Medical science monitor : international medical journal of experimental and clinical research, 2005

The goal was to review the visual and anatomical outcome of scleral buckling for primary rhegmato... more The goal was to review the visual and anatomical outcome of scleral buckling for primary rhegmatogenous retinal detachment at a tertiary eye care center in Nigeria between January 1994 and December 2000. This was a retrospective, descriptive case series of all eyes that had undergone scleral buckling over a 7-year study period. Data collected from the case notes included duration of symptoms, visual acuity at presentation and 3 and 6 months post-op, clinical presentation of the detachments, risk factors for retinal detachment, the surgical procedure done, anatomical outcome at discharge and at 3 and 6 months post-op, and intra-op and post-op complications. Ninety-eight eyes of 98 patients underwent scleral buckling for primary rhegmatogenous retinal detachment during the study period. The mean age was 42 years. The male-to-female ratio was 3.7:1. The mean duration of symptoms was 29.7 weeks. Seventy-six eyes (77.6%) had subtotal to total retinal detachment, with 91 (92.9%) eyes havi...

Nigerian Journal of Medicine, 2008

In order to have baseline data for monitoring and evaluation of trachoma control activities in Sa... more In order to have baseline data for monitoring and evaluation of trachoma control activities in Sabon Birni LGA of Sokoto state Nigeria, a population based trachoma survey was conducted. The survey was designed to determine the prevalence of active trachoma and trichiasis as well as assess the prevalence of major risk factors for trachoma in the study area. The survey was a population based cross sectional survey of persons of all ages in the study area. A minimum sample size of 2760 was determined and the study population was selected by two stage cluster random sampling technique. In the first selection stage 34 communities were randomly selected by probability proportional to size, while for the second sampling stage 90 persons of all ages were randomly chosen in each selected cluster. All chosen persons were assessed for trachoma using WHO trachoma simplified grading system and their households were assessed for trachoma environmental risk factors. The prevalence of blindness in the study population was 2.0% (95% CI 1.4%-2.6%) with trachoma responsible for l3.8%. The prevalence of active trachoma amongst children (1-9 years) was 37% (CI 34.3%-39.8%), while trichiasis amongst adults was 2.3% (95% CI 1.9%-2.7%). Over sixty percent of households had no functional latrine, while 81% of households had refuse and animal dung littered within their compounds. Sixty percent of children had &amp;amp;amp;amp;amp;#39;unclean faces&amp;amp;amp;amp;amp;#39; and over 85% of households had access to water within their villages. Trachoma of public health concern still exists in some districts of northern Nigeria with significant environmental risk factors.

Middle East African Journal of Ophthalmology, 2014

Childhood blindness and visual impairment (CBVI) are major disabilities that compromise the norma... more Childhood blindness and visual impairment (CBVI) are major disabilities that compromise the normal development of children. Health resources and practices to prevent CBVI are suboptimal in most countries in the Eastern Mediterranean Region (EMR). We reviewed the magnitude and the etiologies of childhood visual disabilities based on the estimates using socioeconomic proxy indicators such as gross domestic product (GDP) per capita and <5-year mortality rates. The result of these findings will facilitate novel concepts in addressing and developing services to effectively reduce CBVI in this region. The current study determined the rates of bilateral blindness (defined as Best corrected visual acuity(BCVA)) less than 3/60 in the better eye or a visual field of 10° surrounding central fixation) and functional low vision (FLV) (visual impairment for which no treatment or refractive correction can improve the vision up to >6/18 in a better eye) in children <15 years old. We used the 2011 population projections, <5-year mortality rates and GDP per capita of 23 countries (collectively grouped as EMR). Based on the GDP, we divided the countries into three groups; high, middle-and low-income nations. By applying the bilateral blindness and FLV rates to high, middle-and low-income countries from the global literature to the population of children <15 years, we estimated that there could be 238,500 children with bilateral blindness (rate 1.2/1,000) in the region. In addition, there could be approximately 417,725 children with FLV (rate of 2.1/1,000) in the region. The causes of visual disability in the three groups are also discussed based on the available data. As our estimates are based on hospital and blind school studies in the past, they could have serious limitations for projecting the present magnitude and causes of visual disabilities in children of EMR. An effective approach to eye health care and screening for children within primary health care and with the available resources are discussed. The objectives, strategies, and operating procedures for child eye-care are presented. Variables impacting proper screening are discussed. To reach the targets, we recommend urgent implementation of new approaches to low vision and rehabilitation of children.

Reviews, 1996

References to studies excluded from this review 8 Face washing promotion for preventing active tr... more References to studies excluded from this review 8 Face washing promotion for preventing active trachoma (Review)