Gum exudates of Acacia senegal linn is an alternative binding agent in Drosophila melanogaster culture for laboratory maintenance of stocks

The gum exudates of Acacia senegal Linn was utilized as a single agent or in combination with agar-agar in the formulation of Drosophila diet. Eight (8) corn-meal diets were formulated in two sets consisting of 15 – 40 % (w/w) A. senegal as a single binding agent or a mixture of A. senegal in the ratios of 1:5, 1:2, 1:1 and 2:1 to agar-agar per 100 g corn-meal diet. Biochemical markers of toxicity were analyzed spectrophotometrically. Standard methods of AOAC were employed to determine the physicochemical and proximate compositions of the formulated corn-meal diets. The results from this study showed high level of safety of the gum on adult Drosophila melanogaster (Harwich strain) of both sexes and of the same lineage. LC50 > 100 mg/g with insignificant mortality in all groups at varying concentration (1 – 100 mg/g) of the gum exudate was observed after 7 days of treatment. Significant increases in eclosion in the A. senegal – exposed flies at concentrations of 2, 4 and 5 mg/g diet was also observed after the treatment. A normal trend in locomotor activity was observed in all groups when flies were subjected to negative geotaxic assay, however, at concentrations of 50 mg/g there was an impairment in locomotion. The formulated A. Senegal containing diets have shown varying differences in physicochemical properties, even though no significant changes in the biochemical parameters including SOD1, Catalase and GST in all groups were seen. The collective findings of the present study revealed that the gum exudates of A. senegal L. may be a cost-effective alternative of agar-agar in corn-meal diet for laboratory maintenance of Drosophila melanogaster stocks

Waste Concrete Structure Used as Construction Material

The thesis topic is how concrete demolition waste (CDW) can be crushed, recycled, and used in different forms as concrete materials. The aim is to underline how CDW usage affects the European Union countries' economies and the environment concerning their legislations. The impact of recycled CDW has both negative and positive environmental consequences. The total amount of CDW produced each year in Europe, the amount of CDW recycled, the amount used for backfilling, and the amount that goes to the landfills annually. In addition, it prevents concrete waste from affecting the environment of European countries. The thesis uses Eurostat’s online data to analyze the annual CDW produced in three European countries: Germany, Finland, and The United Kingdom. There are differences in the use of CDW recycling in each country, the quantity that goes to backfilling and landfills annually, economic aspects of these member states' CDW recycling, and the impact of CDW on their environment. In addition, the legislation of each country governing the recycling of CDW emphasizes positive shifts that affect the environment, health, and the economy. The analysis reveals that the use of concrete demolition waste (CDW) minimizes the rate of concrete waste going to landfills and again reduces the usage of natural materials such as rock, clinker, and natural coarse aggregates. The construction of extensive artificial grounds, high depth filling, and the building of pavements and roads can be substituted with recycled waste concrete to give it a second chance of usage. In addition, the advantages, and disadvantages of CDW before and after recycling are considered, as well as the diversion of accuracy in data collection of CDW in both construction sites and each European Union member state