The objective of this paper is to evaluate various experimental techniques and analysis methods for the characterization of interlaminar fracture toughness, and to determine the effects of strain rate on that property for a graphite/epoxy composite. Mode I interlaminar fracture was investigated by means of a double-cantilever beam (DCB) specimen for AS-4/3501-6 graphite/epoxy. Hinged tabs were used to insure unrestrained rotation at the free ends. Specimens were loaded at quasi-static deflection rates of up to 8.5 mm/s (20 in./min) corresponding to crack extension rates of over 51 mm/s (2 in./s). Crack extension was monitored by means of strain gages mounted on the surface of the specimen, or a conductive-paint circuit attached to the edge of the DCB specimen. Continuous records were obtained of load, deflection, and crack extension for determination of the strain energy release rate. The latter was expressed as a power law of the crack extension velocity. Results indicate that the strain energy release rate increases with crack velocity by up to 28% for the range of rates considered here.

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Background:In recent years commercial motorcyclists (Okada riders) have come to bridge the huge public transport gap in most cities across the country. However, this is not without the dangers they pose to themselves, passengers and to other road users. It is claimed that some of these Okada riders operate under the influence of drugs and other substances. But there are few community-based studies that have investigated the problem in this part of Nigeria. Therefore, this study was conducted to determine the prevalence, health and social consequences of psychoactive substance use among commercial motorcyclists (Okada) in Zaria, northern Nigeria. Method: Multi-stage sampling technique was used to sample commercial motorcyclists registered with commercial motorcyclists union in Zaria city, Kaduna state, Nigeria. Structured, closed ended and interviewer administered questionnaires were used to collect information on socio-demographic characteristics, factors influencing psychoactive substance use, impact on health status, motor cycle riding experience and work performance. Results: Two hundred commercial motor cyclists were interviewed, majority of them were in the age group 21-25 years (55.5%) with a mean age of 25.4 ± 3.9 years. All the motorcyclists were male, (60.5%), had no formal education, (79.5%) are of Hausa extraction and (69%) worked for more than 10 hours per day. A high prevalence of 59.5% of road traffic accident that was associated with the use of psychoactive drugs was found among the motorcyclists. Commonly identified psychoactive substance/drugs used were: marijuana [Indian hemp] 25.8%, solution 24.5%, caffeine (Kola) 15.8%, and coffee 4.8%. Keeping awake, suppression of fatigue, and peer group effect were the identified factors influencing psychoactive substance use. The commonest types of injuries sustained were bruises and lacerations (62.5%) and fractures of upper and lower limbs (10.5%). Conclusion: Road traffic accidents among commercial motorcyclists are a frequent occurrence in this part of the country. There is need for public awareness campaigns on road safety education and health consequences of psychoactive substance use among commercial motorcyclists. It is further recommended that law enforcement agencies (NAFDAC, NDLEA and FRSC) need to work in tandem so as to curb the problem of substance abuse in our society and reduce the rate of accidents on Nigerian roads. Key words: Commercial motorcyclists, psychoactive substance, health consequencesUse of psychoactive substances among commercial motorcyclists in Zaria, Nigeria. Alti-Muazu M. and Aliyu A. A. Page | 68Résumé Culture générale: de nos jours, les motocyclistes utilitaires sont les sauveurs de nos jours en ce qui concerne la transportation publique ; pourtant, a cause de leurs activités, ils se livrent aux dangers ; ils mettent aussi les passagers et les autres véhicules en danger il se peut que certains de ces motocyclistes soient toujours sous l'influence de la drogue. A travers les études de certaines communautés, on a...

Background: Despite malaria being the largest public health problem in Africa South of Sahara with over one million associated deaths each year, there has been little progress in its prevention/control during the past decades. Therefore, this study was conducted to determine the knowledge, attitude, use of insecticide-treated nets (ITNs), and the prevalence of malaria episodes among boarding secondary school pupils in Zaria, Nigeria. Methods: A multi-stage sampling technique was used to sample fi ve (5) secondary schools within Zaria, from which six classes (JSS 1 -3 and SS 1-3) of respondents were then randomly selected. Structured, closed-ended selfadministered questionnaires were used to collect information on demographic characteristics, knowledge, attitude, and use of ITNs, reasons for non-use and malaria episodes in last 12 months. Results: A total of 150 students from the fi ve (5) boarding secondary schools were interviewed, majority were in the age group 15-17 (53.3%) with a mean (x) ± SD of 16.8 ± 0.8 years. Males were 60% and females 40% of respondents. Majority of the respondents (87.3%) knew about and had actually seen an ITN; only 43.3% were current users. Most of the current users of ITN noticed a signifi cant reduction in malaria episodes in the last 12 months. This was statistically signifi cant (P=0.004). Cost and availability were reasons sited by non-ITN users. Conclusion: There is urgent need on the part of all the three tiers of Government for public health awareness campaigns through information, education and communication (IEC) to create positive ITN culture and usage. It is also suggested that ITN usage among boarding school pupils should be incorporated into school health service.

Background: Household expenditure on health is increasingly becoming a major source of health care financing in Nigeria. Recognizing the limitations of this pattern of financing health care, the government has introduced a social health insurance scheme policy that has provided for government meeting the health care costs of children. However, there is a dearth of information on the pattern and costs of under-five illnesses at community level. This study therefore sought to determine the magnitude and causes of illnesses among under-fives, sources of healthcare and out of pocket expenditure among children under-five in Layin Zomo, a semi-urban area of Northern Nigeria