THE EFFECT OF DISSOLVED PLASTIC POLYMER MODIFICATION ON RUTTING AND FATIGUE RESISTANCE PROPERTIES OF WARM BITUMEN BLEND

Recently, large amounts of waste polymers are being generated in Nigeria. One of the waste polymers is plastic bottles. Hot Mix Asphalt (HMA) are produced at high temperatures with high energy consumption and environmental hazard. The purpose of using Warm Mix Asphalt (WMA) is to reduce the production and laying temperature and emission of greenhouse gases. Therefore, this research investigated the effect of Dissolved Plastic Bottle (DPB) on the rheological, rutting and fatigue resistance properties of warm bitumen blend thereby reducing the environmental hazard associated with the Waste Plastic Bottles (WPB) disposal and consequently improving pavement service life. WPB was obtained from different waste generation points in Adeleke University, Ede, Nigeria. The obtained WPB was shredded and converted to dissolved form using pyrolysis machine @ 4500C. 500g of 60/70 penetration grade bitumen was heated in an oven with 3% (15g) sasobit until it becomes fluidal. The bitumen was modified with 0 - 17% by weight of the bitumen at 2% interval. Mixing was continued for 1hour to produce homogenous bituminous mixtures. Rheological tests were then conducted on the prepared samples using the Brookfield programmable rheometer. The results indicated that addition of DPB improves the rheological properties of absolute viscosity, phase angle, complex shear modulus, rutting and fatigue resistance of modified binder at both 135°C and 165°C. Therefore, DPB can be used to improve bitumen rheological properties and subsequently resist rutting and fatigue on traffic roads. This can best be achieved upon 7% and 5% modification levels at 135°C and 165°C respectively

Wear minimisation in concrete with haematite

Haematite served as a replacement at 15, 30, 45 and 60 vol.-% for typical limestone based aggregates. Wear tests were performed on those specimens under 100, 200 and 300 kPa compression. A statistical response surface method (RSM) was used to evaluate the effects of concentration of cement and haematite on wear. The method allows among others optimisation of the haematite content with respect to wear. For a fixed content of cement, RSM tells us to increase the content of haematite to lower wear. © W. S. Maney & Son Ltd. 2013

Genetic factors and the role of pancreatic amylase in the pathogenesis of type 2 diabetes

Abstract This review article gives an insight into the genetic factors and the role of pancreatic amylase in type 2 diabetes (T2D). Diabetes is a non-communicable, multifactorial, heritable, complex, and irreversible disease of public health burden with a global prevalence rate of 6.28%, about 6% in sub-Saharan Africa, and 1.7% in Nigeria. T2D is recognized as the ninth leading cause of mortality worldwide. This disease is yet to be diagnosed in a significant number of people who live with it in underdeveloped and developing countries like Nigeria due to the lack of free or subsidized access to health care, especially medical checkups, inadequate health facilities, government policies, and negligence. Consequently, undiagnosed cases of T2D have contributed to the prevalence of this disease and its comorbidities -hypertension and chronic kidney disease. Obesity, age, race and ethnicity, inactivity, family history, underlying illness, and unhealthy diets are prominent undisputable predisposing factors of T2D. Pancreatic amylase is a type of amylase produced in the pancreas, known to hydrolyze starch and prone to mutations, but most of the genetic components, causative polymorphisms, and affected genes are yet unknown. Even as insulin secretion is found to be influenced by the loci, the causation of T2D cannot be inferred. Pancreatic amylase was observed to be the most relevant digestive enzyme, whose role is to bind to glycoprotein N-glycan to activate starch digestion. In a malfunctioning pancreas, little or no insulin is generated to keep the blood glucose at an appropriate level, thereby resulting in T2D