Sequencing batch reactor technology for landfill leachate treatment: A state-of-the-art review.

Landfill has become an underlying source of surface and groundwater pollution if not efficiently managed, due to the risk of leachate infiltration into to land and aquifers. The generated leachate is considered a serious environmental threat for the public health, because of the toxic and recalcitrant nature of its constituents. Thus, it must be collected and appropriately treated before being discharged into the environment. At present, there is no single unit process available for proper leachate treatment as conventional wastewater treatment processes cannot achieve a satisfactory level for degrading toxic substances present. Therefore, there is a growing interest in examination of different leachate treatment processes for maximum operational flexibility. Based on leachate characteristics, discharge requirements, technical possibilities, regulatory requirements and financial considerations, several techniques have been applied for its degradation, presenting varying degrees of efficiency. Therefore, this article presents a comprehensive review of existing research articles on the pros and cons of various leachate degradation methods. In line with environmental sustainability, the article stressed on the application and efficiency of sequencing batch reactor (SBR) system treating landfill leachate due to its operational flexibility, resistance to shock loads and high biomass retention. Contributions of integrated leachate treatment technologies with SBR were also discussed. The article further analyzed the effect of different adopted materials, processes, strategies and configurations on leachate treatment. Environmental and operational parameters that affect SBR system were critically discussed. It is believed that information contained in this review will increase readers fundamental knowledge, guide future researchers and be incorporated into future works on experimentally-based SBR studies for leachate treatment.

Giant Cell Tumour of Distal Left Tibia: A Case Report.

Giant cell tumours of bone are relatively uncommon, accounting for about 5% of all primary bone tumours. They are generally classified as benign bone tumours. However, some of them might be locally aggressive. The peak incidence is between second and fourth decades of life. They are commonly found at the epiphyseal and, occasionally, metaphyseal zones of long bones such as radius, femur and tibia. They most often present as painless swellings; however, pain may be experienced as a result of pressure on the surrounding soft tissues. The relevant diagnostic investigations that help in establishing the diagnosis include plain x-rays, Magnetic resonance imaging (MRI), CT and tissue biopsy for histological confirmation. Traditionally, surgery is the mainstay of treatment of the disease. Other modalities include radiation, tumour embolization and injectable drugs for surgically inaccessible or recurrent cases.

Premarital sexual experience and preferred sources of reproductive health information among young men in Kumbotso, northern Nigeria.

BACKGROUND: Despite well known risks associated with unprotected premarital sex, this phenomenon has not been well explored among young men in rural northern Nigeria. We studied the predictors of premarital sex and preferred sources of sexual and reproductive health information among young unmarried men in Kumbotso, northern Nigeria. METHOD: A cross section of 400 young men were interviewed using structured questionnaires with mostly closed ended questions. RESULTS: Of the 385 respondents, 39 (10.1%) were sexually experienced. Less than half of respondents (48.7%) used a condom at sexual debut, and an equal proportion reported having multiple sex partners. Only 41.0% of sexually experienced respondents reported subsequent consistent condom use Age (adjusted odds ratio [AOR] = 4.12; 95% confidence interval (CI): 2.24-5.20 and educational attainment [AOR = 3.57; 95% CI (1.49-9.10)] were significant predictors of sexual experience. The current versus preferred sources of sexual and reproductive health information included friends (51.3% vs. 93.3%), Islamic school teachers (41.0% vs. 72.7%) and school teachers (8.8% vs. 15.1%). CONCLUSION: Although the prevalence of premarital sex among young men in this community in northern Nigeria as low, those that did engage in such activity were likely to not use condoms and to have multiple partners. Preferred and trusted sources of information included peers and religious leaders. The findings in this study could be used to develop innovative strategies for reaching young men with accurate sexual and reproductive health information.