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Accessing temporal trend of different meteorological parameters is essential for understanding the local climate changing pattern of a region. Quantitative estimates of the effect of climate change helps in understanding, planning, and management of water resources systems. In this study, monthly meteorological data were collected from 30 stations of north-east (NE) India for 1971–2010 and non-parametric Mann-Kendall (MK) test and Sen slope were employed for detection and quantification of significant temporal trends, respectively. An ESRI ArcGIS toolbar “ArcTrends” was used for the above mentioned tasks. The results obtained for rainfall were of mixed nature and both increasing and decreasing significant trends were found for different stations in different months. Most of the negative trends were found in the months of July–August (monsoon), whereas, more stations showed positive trends in April–May (pre-monsoon), and October–November (post-monsoon), indicating inter-seasonal shifting of rainfall without much change in the annual total. Number of rainy days was found to have positive trends in March–May (pre-monsoon) and negative trends in September–December. Except some positive trends during June–December in Manipur and Meghalaya, there were no significant trends in maximum temperature. In some stations, minimum temperature was found to have significant increasing trends throughout the year indicating a general rising trend in NE India. Some major towns like Guwahati, Imphal, Agartala and Kailashshahar showed significant positive trends in mean temperature, mostly during June–December. Mean relative humidity was, in general, found to be significantly increasing, especially during February–March. In some stations, wind speed was found to have significant negative trends throughout the year, with Agartala being the most affected.

One of the fundamental carotenoid compounds available in microalga Chlorella pyrenoidosa is lutein, which is a commercially valuable antioxidant compound. The extraction of lutein from C. pyrenoidosa was studied in detail under various operating conditions. Acid pretreatment was done using 10% HCl. To analyze the effectiveness of ultrasound based extraction, experiments were carried out in presence and absence of ultrasonication. The results showed increased lutein yields in presence of ultrasonication. Scanning electron micrographs of pretreated and ultrasonicated algae cells showed increased surface area due to formation of porous surface. There were no significant contrasts in antioxidant activity of lutein between the samples obtained from ultrasound and acid treatment. Furthermore, to optimize the operating parameters like concentration of HCl, ultrasound exposure time and microalga biomass concentration, response surface methodology (RSM) design was applied. From the experimental results the optimum values derived are incubation time 41.34 min, HCl concentration 15.63 % and biomass concentration 309.21 g/L for a yield of 3.5 mg of lutein per gram of algae. Hence, ultrasound extraction with acid treatment is the most efficient technique for the extraction of microalgal lutein.

In recent years children’s head hair is a biomarker frequently used for monitoring environmental exposure to heavy metals. Blood, plasma, urine and other tissues analysis were the most popular approaches to evaluate the concentrations of trace elements in human body. However, hair sample is easily collected, stored and readily analyzed. As (arsenic), Cd (cadmium), Hg (mercury), Ni (nickel) and Pb (lead) poses a potential threat to humans. The aim of the study is to link the concentrations of heavy metals in children’s scalp hair with the environmental pollution by presenting an overview of the measurements that have been done in 12-year-old children’s scalp hair living at the municipalities of Kifisia and Kryoneri, in relation with trace metals concentrations in the river water, air and tree leaves at the north zone of Kifissos River in Athens, Greece.

Disinfection by-products (DBPs) can be controlled by using alternative disinfectants to chlorine, removing DBPs precursors prior to chlorination and removing DBPs after formed. Chloramine is widely used as an alternative disinfectant to chlorine usage. In this study to evaluate trihalomethanes (THMs) and haloacetic acids (HAAs) formation and speciation for Altinapa and Omerli dam water isolates after chlorination and choramination procedures at different pH values was aimed. Compared with chlorination, the formation of THMs was reduced by approximately 4-fold in chloramination for Omerli dam water. Total THM concentrations remained below detection limits in Altinapa isolate after chloramination. The dominant species were CF and followed by BDCM and CDBM in case of chlorination, and almost no BF formed. BF is the dominant specie together with CF in case of chloramination, and no BDCM and CDBM formed at all pHs for Omerli dam water. HAA concentrations resulting from the use of chlorine were obtained 4.8-5.1 times higher from resulting from the use of chloramines at different pH values for Omerli Dam water; but this value was 5.5-8.7 for Altinapa Dam water. MCAA, DCAA and BCAA concentrations were a large part of the total HAA concentrations which obtained from chloramines usage for both isolates.