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A study involving grain size analysis was carried out from the Parsons valley lake deposit, Nilgiris, India to determine the depositional environments and paleoflood events since late Pleistocene period (∼29,838 cal yr BP). A 72 cm lacustrine core was collected from the lake and eight organic rich sediment samples were AMS radiocarbon dated. The study reveals variations in the grain size distribution chiefly influenced by regional climatic conditions. Paleoflood events have been identified by the individual sedimentary flood signatures of varying changes in the magnitude of sediment supply from the background silty sediment matrix around ∼29,838 and ∼8405 cal yr BP.

Earlier studies on the ferricrete of Sriperumbudur Formation were focused on their types of occurrences and mode of formation. However, in the present study, an attempt is made to understand the physico-chemical changes across seven saprolite-ferricrete profiles developed over sedimentary protolith after upliftment to decipher the paleoenvironmental conditions to which the Sriperumbudur Formation was exposed and to understand the processes of ferricretisation. For this purpose, the ferricrete exposures around Sriperumbudur were surveyed and mapped for their occurrences and types of ferricretes, collected samples were examined for various physio-chemical aspects. Geochemical and petrographic studies exhibit a relatively high percentage of iron content. The Fe2O3 content varies from 7.71% to 14.9% followed by the higher concentration of Al2O3 and SiO2 as a result of deep weathering of the Sriperumbudur beds. Other major oxides such as CaO, MgO, Na2O, K2O, MnO and TiO2 show lower concentrations. The bulk X-ray diffraction of the ferricrete samples shows the occurrence of tourmaline, muscovite and magnetite. SEM analysis of the ferricrete samples exhibits solution channels and pits in the matrix, on the limonite, quartz and magnetite revealing intense chemical weathering. Petrographic studies show the occurrence of quartz in a variety of shapes, sizes and sediment sorting, cemented by iron oxides in varying stages. It also reveals iron oxide mobilization due to the alteration of ferruginous sandstone forming a hard ferricrete crust. Iron oxide cementation is due to leaching and re-cementing from the parent sedimentary rock with subsequent re-deposition of the earlier material taking place in a near shore environment and in wetter conditions after the Sriperumbudur beds were exposed since the lower Cretaceous period.

In this paper, We using the cluster-based prediction, to predict the keywords over database in a efficient way. By using the cluster-based prediction, efficiency of searching query is improved and time complexity is reduced. In this paper, we proposed Text preprocessing, MVS matrix, k-means clustering and character shuffle preprocessing searching algorithm in order to improve efficiency. In text preprocessing, we eliminates all the tags and find the relative frequencies of each document then weights is calculated. By using MVS matrix, similarities of each document is calculated then formed into matrix. Based on similarities, Clusters are formed by using K-means clustering, then the keyword is searched in clustered instead of several documents. Then the searching is performed in efficient way.

The freshwater teleost Tilapia mossambica was subjected to lethal (6.0 mg X liter-1 = LC50/48 hr) and sublethal (1.5 mg X liter-1 copper treatment for 1, 7, and 14 days. The whole animal oxygen consumption and the activity levels of succinate dehydrogenase and lactate dehydrogenase in liver and muscle were studied. The decrease in oxygen consumption and succinate dehydrogenase activity and significant increase in lactate dehydrogenase activity suggest that the stressed fish is meeting its energy requirements through anaerobic oxidation and these enzymes can be used as indicators in monitoring metal-induced toxicity in fish.