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Microplastics are ubiquitous, and their widespread prevalence in the ecosphere has generated concerns about their potential effects on terrestrial and aquatic organisms. However, studies pertaining to ecologically sensitive freshwater ecosystems, such as Ramsar wetlands, is scarce. Therefore, the study was conducted in Loktak, the world's only floating lake, and one of the largest wetland in the Indian Himalayan region. The wetland's degradation and pollution have resulted its inclusion in the Montreux Record, underscoring the need for studying this eco-sensitive freshwater system. This work investigated the (i) abundance, morphotype and size of microplastics in fish, and (ii) chemical composition of the microplastics consumed and accumulated in the fish of Loktak lake. Fish samples representing eight species were collected and analyzed for microplastics. Results revealed that ∼91% of the sampled fish ingested microplastics. Fragment was identified as the predominant morphotype (∼82%). Plastic polymers including polyamide (PA), polystyrene (PS), polycarbonate (PC) and carboxymethyl cellulose (CMC) were detected. The occurrence of heavy metals - chlorine (Cl), palladium (Pd), sodium (Na), zinc (Zn), lead (Pb) and copper (Cu) suggests their adhesion on the microplastics. The occurrence of microplastics in fish indicates pollution in the lake and poses a potential health risks to humans through consumption. Therefore, implementing comprehensive management approaches is imperative to mitigate this emerging pollution and uphold the ecological integrity of the Ramsar site. Substantial information on microplastics and their potential human exposure through fish consumption, particularly in the Indian Himalayan region, remains to be assessed, underscoring the need for extensive study. [Display omitted] • First report on microplastic pollution in fishes from the Indian Himalayan Region. • Ninety one percent of the studied fish individuals were detected with microplastics. • Microplastic fragments were the predominant morphotype in the fish. • No relation was found between fish body length/weight with the microplastic content. [ABSTRACT FROM AUTHOR]

Some novel 5-aminoalkylbarbituric acids and corresponding chromene derivatives were synthesized via a one-pot, three-component Mannich reaction starting from 1,3-dimethylbarbituric acid, arylaldehydes, and amines. [ABSTRACT FROM AUTHOR]

Crop residue burning is a major environmental issue and their potential long-term impact on the climate is a global concern. A laboratory experiment was carried out to study the impact of biochar on carbon loss from tropical soils. Residues of two important foodgrain crops viz, rice and wheat were used to prepare respective biochar and added as amendments in two different tropical agricultural soils (red and alluvial). In general carbon loss was more from alluvial soil than red soil. In alluvial soil, carbon loss was more when biochars were applied along with N fertilizer (urea) than biochar alone. Increasing rate of application of rice biochar without urea showed potential carbon protection in alluvial soil. Interestingly, unlike rest of the treatments, carbon loss was more in red soil when wheat biochar was applied without urea than with it. While physicochemical characteristics of biochars play crucial role in carbon protection, the intrinsic nature and properties of soil largely regulates it. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 183-188, 2016 [ABSTRACT FROM AUTHOR]

Drying conditions for X anthosoma sagittifolium tubers were optimized using response surface methodology. A face-centered central composite design with two numerical factors and one categorical factor was selected for conducting the experiments. The numerical factors selected were air temperature from 50 to 70C, and drying time from 4 to 8 h while shape of the cut tubers i.e., slices or cubes was the categorical factor. The responses investigated were water loss, final moisture content, rehydration coefficient and peak viscosity. The study revealed that the effect of all the factors was significant on the responses. The optimum condition obtained using the desirability function for achieving the desired product was found at the temperature of 68.57C and the drying time of 5.51 h for slices. The values of moisture content, water loss, rehydration coefficient and peak viscosity at the optimum drying condition were 0.43% dry basis, 68.55 g/100 g sample, 0.84 and 4039.4 cP, respectively. Practical Applications The tubers of X anthosoma contain reasonable amounts of calcium, phosphorus, and vitamins A and B. The starch present in X anthosoma tubers is easily digestible because of its small granule size. The protein and dietary fiber content of the edible portion is also high as compared with other root and tuber crops. It can be used in the preparation of baby foods and diets of people allergic to cereal proteins. Although the production of X anthosoma sagittifolium is high worldwide and has the potential of meeting the energy requirements of the consumer because of its high starch content and better starch quality, there are very few studies related to drying of X . sagittifolium tubers to increase the shelf life of the product. Therefore, the present study becomes important as proper understanding of the drying process of X anthosoma tubers is necessary for the process to become industrially feasible. [ABSTRACT FROM AUTHOR]

The city of Guwahati has a rich historical past and finds frequent mention in medieval historical sources and epics. From the pre-historic existence, the city has evolved through various stages of development and lately, the city has entered a phase of vigorous growth changing remarkably its fabric of settlement and the overall morphology of the urban landscape. Throughout the history of growth and development of Guwahati city, the river Brahmaputra has played the most important role in shaping the socio-economic life of its dwellers and the land use pattern of the city. The river still continues to play a unique role in maintaining the city's scenic beauty, grandeur, health and prosperity. In fact the nourishing presence of the river in the heart of the city provides a variety of facilities and opportunities to the city dwellers, some of which are, however, directly visible, while many others need careful observation for assessing their contribution. Of late, this eco-city has also been witnessing a severe demographic hazard because of migration of people from other parts of Assam and the Northeast as place of opportunity. The growing urban congestion and extension of human settlement, roads and other constructions to the marginal and delicate areas like the hill slopes, fringes of the beels, wetlands and rivulets have now made the city's drainage highly complicated and increasingly inefficient. These have caused some severe problems such as killer landslide, erosion, water logging and flash flood. [ABSTRACT FROM AUTHOR]

Abstract: Pyrimido[4,5-d]pyrimidine derivatives 4 have been prepared in an efficient and regioselective manner in water via multi-component reaction of isothiocyanate 1, aromatic aldehyde 2, N,N-dimethyl-6-amino uracil 3 in the presence of p-toluenesulfonic acid (p-TSA) as a Lewis acid catalyst. [Copyright &y& Elsevier]

This study reports the environmental fate and ecological hazard of the three heavy metals (HMs), viz. copper (Cu), manganese (Mn) and zinc (Zn) in soil influenced by municipal solid waste (MSW) dumping. The experimental site is situated in the vicinity of Deepor Beel, a Ramsar site located in Guwahati, India. This study assessed (i) the distribution pattern of Cu, Mn and Zn in six geochemical fractionations; (ii) the mobility, bioavailability and toxicity of Cu, Mn and Zn based on eight contamination and ecological indices, and (iii) the impact of Cu, Mn and Zn on soil quality. Altogether, 18 soil samples were collected and analysed from the study site using stratified random sampling. Pollution indices and multivariate statistics were applied on the data to identify the level and source of analysed HMs. Sequential extraction has revealed that the binding strength of Cu, Mn and Zn had a uniform trend. Mobility and potential bioavailability of studied HMs were in the order Mn > Cu > Zn. Analysed HMs were dominantly associated with non-bioavailable fractions. The observed low values of various contamination factors indicated the lesser contamination load posed by these metals. Conversely, their high enrichment factor and geo-accumulation index values indicated the sources of these metals were anthropogenic. Overall, the pollution and ecological indices registered lower contamination. Yet, it would be prudent to adopt efficient MSW management strategies for eliminating any future risk emanating out of this dumping site and posing threat to nearby Deepor Beel and its associated flora and fauna. Image 1 • Environmental risks associated with three heavy metals (Cu, Mn and Zn) in the soils were determined. • Municipal solid wastes (MSW) containing heavy metals (HM) pose ecological risk. • Major sources of these HMs were anthropogenic in nature. • Scientific waste management is needed to protect Deepor Beel, a Ramsar site. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the chemical formula for the derivatives of barbituric acid, and the synthesis and function of annulated barbituric acids.

The reaction of uracils, aryl halides and 3-cyanoacetyl indole produces the pharmaceutically interesting title compounds (IV) and (VII). [ABSTRACT FROM AUTHOR]