Showing papers in "Current Science in 2017"
TL;DR: A major upgrade of the Giant Metrewave Radio Telescope is nearing completion that will increase its sensitivity by up to three times and make it a more powerful and versatile facility.
Abstract: The Giant Metrewave Radio Telescope (GMRT) is today a frontline international facility for lowfrequency radio astronomy, that has produced several exciting and important new results in the 15 years that it has been operational. To keep the GMRT competitive in the global arena in the future, a major upgrade of the observatory is nearing completion that will increase its sensitivity by up to three times and make it a more powerful and versatile facility. We describe the main goals of this upgrade, highlight the technical features and challenges, outline the science potential and update the current status of this venture.
174 citations
TL;DR: In this article, the authors investigated the surface, physical and chemical characteristics of large volume-fruit peels (FP) with a view to propose their valorization in detail.
Abstract: Globally, India is the leading producer of fruits. Fruits after consumption leave a peel which is a nuisance to the environment as a solid waste. In this article, commonly available large volume-fruit peels (FP) (viz. banana, orange, citrus, lemon and jackfruit) were investigated for surface, physical and chemical characteristics with a view to propose their valorization in detail. Each FP was characterized by proximate and ultimate analysis, porosity, particle density, bulk density, point of zero charge (pH pzc ), surface pH, surface charges, water absorption capacity, BET surface area, scanning electron microscopy, Fourier transform infrared spectroscopy and TGA/derivative of thermogravimetric. The BET surface area of FP is very less, between 0.60 and 1.2 m 2 /g. The pH pzc and surface pH values of orange peel (OP), citrus peel (CP), lemon peel (LP) and jackfruit peels (JFP) are in the range of 3-4. The pH pzc value and surface pH of banana peel (BP) is closer to 7. The order of surface acidity is OP > LP > CP > JFP > BP. From TG curves it is clear that FPs are stable below 150°C. The results will be useful for rational design, when FP is used as a substrate for bioactive compounds, phenolic antioxidants, organic acids, enzymes, biofertilizer, production of energy and as adsorbents.
165 citations
TL;DR: In this paper, an extended version of the notable work by the pioneering researchers Sandro Stringari and Lev Pitaevskii, which first appeared in 2003, is presented.
Abstract: This book on Bose–Einstein condensation (BEC) and superfluidity, is an extended version of the notable work by the pioneering researchers Sandro Stringari and Lev Pitaevskii, which first appeared in 2003. The first edition appeared to be a detailed version of a review paper ‘Theory of BEC in trapped gases’ that appeared in the Review of Modern Physics in 1999 by the same authors and their two other colleagues. Back in 2005, my research career started with this book and gave me a fresh feeling each time I went through it. It is one of the first books that appeared in the broad area of ultra-cold atoms and deals with the physics of both bosonic and fermionic atoms that are laser cooled to temperatures of the order of nano- or microkelvin.
123 citations
TL;DR: The Winter Fog Experiment (WIFEX) over the Indo-Gangetic Plains of India is to develop better nowcasting and forecasting of winter fog on various time and spatial scales as discussed by the authors.
Abstract: The objectives of the Winter Fog Experiment (WIFEX) over the Indo-Gangetic Plains of India are to develop better now-casting and forecasting of winter fog on various time-and spatial scales. Maximum fog occurrence over northwest India is about 48 days (visibility <1000 m) per year, and it occurs mostly during the December-February time-period. The physical and chemical characteristics of fog, meteorological factors responsible for its genesis, sustenance, intensity and dissipation are poorly understood. Improved understanding on the above aspects is required to develop reliable forecasting models and observational techniques for accurate prediction of the fog events. Extensive sets of comprehensive ground-based instrumentation were deployed at the Indira Gandhi International Airport, New Delhi. Major in situ sensors were deployed to measure surface micrometeorological conditions, radiation balance, turbulence, thermodynamical structure of the surface layer, fog droplet and aerosol microphysics, aerosol optical properties, and aerosol and fog water chemistry to describe the complete environmental conditions under which fog develops. In addition, Weather Forecasting Model coupled with chemistry is planned for fog prediction at a spatial resolution of 2 km. The present study provides an introductory overview of the winter fog field campaign with its unique instrumentation.
86 citations
TL;DR: There has been a significant growth in the neuroimaging literature with North America and Europe being the main contributors and top journals within the field have improved performances over the study period.
Abstract: Neuroimaging is one of the important medical imaging domains that help diagnose and manage diseases. This study describes the neuroimaging publication outputs sorted by journals, countries, authors and institutions, and evaluates journal performance using metrics based on publication data from 2003 to 2014 indexed in the Web of Science and Journal Citation Reports. There has been a significant growth in the neuroimaging literature with North America and Europe being the main contributors. Magnetic resonance imaging is the most popular imaging modality, and brain connectivity is one of the hotspots. Top journals within the field have improved performances over the study period.
54 citations
TL;DR: This paper aims to provide a history of solar eclipses in India and some of the techniques used to achieve this goal have been developed in the last 50 years.
Abstract: B. Raghavendra Prasad*, Dipankar Banerjee, Jagdev Singh, S. Nagabhushana, Amit Kumar, P. U. Kamath, S. Kathiravan, Suresh Venkata, N. Rajkumar, V. Natarajan, Madhur Juneja, Pawan Somu, Vaibhav Pant, Nigar Shaji, K. Sankarsubramanian, Asit Patra, R. Venkateswaran, Abhijit Avinash Adoni, S. Narendra, T. R. Haridas, Shibu K. Mathew, R. Mohan Krishna, K. Amareswari and Bhavesh Jaiswal Indian Institute of Astrophysics, 2nd Block, Koramangala, Bengaluru 560 034, India ISRO Satellite Centre, Old Airport Road, Vimanapura Post, Bengaluru 560 017, India Space Applications Centre, Jodhpur Tekra, Ambawadi Vistar, P.O., Ahmedabad 380 015, India Laboratory for Electro-Optics Systems, First Phase, Peenya Industrial Estate, Bengaluru 560 058, India ISRO Inertial Systems Unit, Vattiyoorkavu PO, Thiruvananthapuram 695 013, India Udaipur Solar Observatory, Near Fatehpur Lake, Shilpgram, Udaipur 313 004, India
53 citations
TL;DR: Significant progress made in rice, wheat, maize and millets for identification of genotypes, development, evaluation and release of the varieties with high nutrient contents and their bioavailability studies is discussed.
Abstract: Food security of the country has been improved due to green revolution and enhancement of cereal
production. However, recent surveys showed 35.8% of children suffer from malnutrition in India.
The Indian Council of Agricultural Research has taken lead for the biofortification of cereal crops
based on earlier national and international research efforts, targeting the enhancement of nutrients
in staple food crops. In this article, the significant progress made in rice, wheat, maize and millets
for identification of genotypes, development, evaluation and release of the varieties with high nutrient
contents and their bioavailability studies is discussed.
52 citations
TL;DR: In this article, the role of conservation agriculture in improving soil physical health and its associated processes is reviewed and the present data indicates that conservation agriculture can improve soil physical properties and associated processes especially, soil, water infiltration and storage, soil aeration, soil structure and soil porosity.
Abstract: Maintenance of soil physical health at its optimum
level is essential for sustainable crop production and
rational use of natural resources without jeopardizing
their quality. The ongoing conventional tillage practices
for crop production using intensive ploughing
and removal of crop residue from the field have
resulted in an increase in surface crusting, soil
compaction, soil erosion, decrease in water infiltration
and ultimately aggravation of the overall soil physical
health deterioration. In recent years, many agricultural
scientists across the world have recommended
conservation agriculture as a solution to overcome the
adverse effects of conventional tillage practices on soil
physical health. Conservation agriculture is mainly an
integration of three crop management practices, viz.
minimum or no-tillage, permanent retention of crop
residue and crop rotation. The present data indicates
that conservation agriculture can improve soil physical
properties and associated processes especially, soil
water infiltration and storage, soil aeration, soil structure
and soil porosity. It reduces soil erosion, soil
compaction and crusting, and optimizes the soil temperatures
for successful crop production. This article
reviews the role of conservation agriculture in
improving soil physical health and its associated processes.
48 citations
TL;DR: In this article, the authors examined the trends in magnitude and intensity of precipitation and peak floods of different magnitudes for seven major river basins in India using data pertaining to daily flows for about 30-odd years and precipitation for 61 years (from 1951 to 2012).
Abstract: The aim of the present study is to examine the trends in magnitude and intensity of precipitation and peak floods of different magnitudes for seven major river basins in India. Data pertaining to daily flows for about 30-odd years and precipitation for 61 years (from 1951 to 2012) were analysed. Linear trends were calculated for the number of rainy days, rainfall intensity and occurrence of flood peaks for all basins. Using the Sen’s slope estimator, it was found that annual peak rainfall increases for most of the basins in India. From the Mann–Kendall test and Sen’s slope, it was found that the Cauvery and Brahamani and Baitarani basins show a rising trend in the number of rainy days, but the trend was falling for five other basins. When the basins were classified as mountains and plains, it was found that the number of daily rainfall events of different magnitudes was more in the mountains compared to the plains. The rivers which flow from west to east direction have more rainy days compared to those which flow towards the west. It was observed that in general the number of rainy days was falling while the number of intense events was increasing. The number of flood peaks of smaller magnitude in different decades showed slight falling trend. It was also found that there was falling or no trend for severe floods. Anthropogenic activities (construction of storage reservoirs, diversions, urbanization, land-use change, and soil and water conservation measures, etc.) have probably affected the generation of peak floods in the rivers of India. River regulation through storage reservoirs in the past 50 years has resulted in the reduction of peak flows. Hence with the same rainfall, the flood peaks would have increased under virgin conditions.
39 citations
TL;DR: It was revealed that all the highly cited papers from India did not receive citations in the early years after publication, and USA was the preferred collaborative partner for international collaboration.
Abstract: The aim of the present study is to analyse the highly cited papers from India. The Science Citation Index Expanded database was used to retrieve the related bibliographic records. Grouping and reclassification of institutions with misspellings and variants have been done. The most productive institutions, collaborating partners and Y-index of the contributing authors were examined. Results revealed that all the highly cited papers from India did not receive citations in the early years after publication. Co-authored (or international collaboration) papers received more citation impact than single-authored ones. USA was the preferred collaborative partner for international collaboration. The Indian Institutes of Technology, CSIR organizations, and Indian Institute of Science, Bengaluru were the leading Indian institutions.
38 citations
TL;DR: In this article, trace elemental data from 39 Paleo-archean (3.43 and 3.25 Ga) zircons separated from quartzite near Girar, which formed a part of the South Bundelkhand Supracrustal Complex in Central India.
Abstract: The present study reports trace elemental data from 39 Paleoarchean (3.43 and 3.25 Ga) zircons separated from quartzite near Girar, which forms a part of the South Bundelkhand Supracrustal Complex in Central India. The zircons are prismatic, have well-developed oscillatory zoning and their Th/U ratio ranging from 0.27 to 8.62 is comparable to that of typical magmatic zircons. Crystallization temperature of 620-776°C using titanium-in-zircon thermometer, positive slope of zircon REE patterns, positive Ce anomalies along with mineral inclusions like quartz, muscovite, magnetite and monazite suggest a granitic source for these quartzites. Sm-Nd isotopic data (T DM age = 3.29 Ga) along with zircon trace elemental data indicate the presence of granitic continental crust in southern Bundelkhand Craton at least during the Paleoarchean (3.4 Ga).
TL;DR: In this paper, the role of earthworms in improving soil structural and functional properties, which serve as key determinants of soil ecosystem services and economic benefits for the farmers, has been discussed.
Abstract: Earthworms commonly occur within the soil. They alter physico-chemical and biological regimes of the soil through their activities, such as burrowing, casting, feeding and propagating, and therefore are known as 'ecosystem engineers'. Through their activities, they provide a number of ecosystem services which are ecologically and socio-economically important. This article reviews the role of earthworms in improving soil structural and functional properties, which serves as key determinants of soil ecosystem services and economic benefits for the farmers. A methodology of economic evaluation of the agro-ecosystem services provided by earthworms has been demonstrated. Further, the information gaps and future research have been discussed for ensuring sustainable agroecosystems management.
TL;DR: Both oxalic acid and calcium oxalate provide self-defence against insect pests and grazing animals and involved in phytoremediation of soils rendered toxic by heavy metals, like lead, cadmium, zinc, etc.
Abstract: Oxalic acid and oxalates are produced and present in plants in different amounts. Insoluble calcium oxalate plays a key role in regulating calcium concentration, which is important in the functioning of guard cells. Oxalates provide tolerance to aluminium toxicity to plants growing in acid soils. Both oxalic acid and calcium oxalate provide self-defence against insect pests and grazing animals. Oxalates are involved in phytoremediation of soils rendered toxic by heavy metals, like lead, cadmium, zinc, etc.
TL;DR: In this paper, the authors analyzed innovation research developed between 1989 and 2013 using the Web of Science database and provided several author-level bibliometric indicators including the total number of publications and citations, and the h-index.
Abstract: Over the last few years, an increasing number of scientific studies related to innovation research has been carried out. The present study analyses innovation research developed between 1989 and 2013. It uses the Web of Science database and provides several author-level bibliometric indicators including the total number of publications and citations, and the h-index. The results indicate that the most influential professors over the last 25 years, according to their highest h-index, are David Audretsch, Michael Hitt, Shaker Zahra, Rajshree Agarwal, Eric Von Hippel, David Teece, Will Mitchell and Robert Cooper. Among these authors, it is possible to demonstrate that they are not necessarily the most productive authors, with the highest number of publications; however, they are the most influential, with the highest number of citations. The incorporation of a larger number of journals to the Web of Science has granted different authors access to publish their work on innovation research.
TL;DR: The spaceborne subsidence monitoring has emerged as a better technique after the development of satellite radar interferometry and the technology is fast improving with enhanced synthetic aperture radar sensors on different spaceborne platforms.
Abstract: Most studies of surface subsidence and its impacts have been done on underground coal mines. There are few studies on the occurrences of surface subsidence in underground metal mines, particularly in India, even though the fundamental subsidence engineering principles are the same for both coal and metal mines. The current ground-based measurement techniques monitor ground subsidence on a particular point and are time-consuming as well as costly. To study hardrock mine surface deformation due to underground mining, new and effective technologies must be adopted. The spaceborne subsidence monitoring has emerged as a better technique after the development of satellite radar interferometry. The technology is fast improving with enhanced synthetic aperture radar (SAR) sensors on different spaceborne platforms. Differential interferometric SAR techniques are widely used to measure the topographic profile and surface deformations. This article reviews the applications of spaceborne SAR interferometric techniques in the prediction and monitoring of surface subsidence due to underground mining.
TL;DR: This article presents a review of wound dressings made of natural and synthetic polymers or a combination of both and a variety of commercial wound healing materials is discussed briefly.
Abstract: Skin injury and wound healing are complex biological and intricate processes that involve activation of intercellular pathways, co-ordination of tissue integrity and homeostasis. The wound can be acute and chronic depending upon the nature and depth of the injury. A wide variety of dressing materials is available to enhance the wound healing process. An ideal dressing should act as a three-dimensional template which can mimic extracellular matrix, be biologically stable, flexible and can remove wound exudate by providing a moist environment to the wound site. It should form a protective bed to cover the wound from external hazards. This article presents a review of wound dressings made of natural and synthetic polymers or a combination of both. A variety of commercial wound healing materials is discussed briefly.
TL;DR: In this paper, the status and pattern of tree-crop combinations of agroforestry practices across various regions of the state as well as productivity under different agro-forestry systems are reviewed.
Abstract: Agroforestry is a dynamic and sustainable land management system of deliberately growing woody perennials along with agricultural crops on farmlands to secure both tangible and intangible benefits to the farmers. Uttar Pradesh (UP), one of the largest and densely populated state of India in the Indo-Gangetic Plain with large agrarian communities, had a paradigm shift in the adoption of agroforestry. After successful adoption and commercialization of poplar and eucalyptus-based agroforestry models over two decades in western UP, other parts of central and eastern UP have also been attracted towards remunerative agroforestry projects in the past few years. In UP, agroforestry practices vary according to different agro-climatic zones, land capability and socio-economic status of farmers. The variation is reflected in terms of diversity in agroforestry practices, and comparative advantage prompted a renewed interest to harness the vivid potential. Drawing on the representative literature, we have reviewed the status and pattern of tree– crop combinations of agroforestry practices across various regions of the state as well as productivity under different agroforestry systems, which shows traditional agriculture transforming to multifunctional agroforestry in UP.
TL;DR: Analysis of molecular variance revealed significantly high genetic variation within Pt population, offering valuable information for framing suitable disease management strategies through appropriate region-specific gene deployment and improving the understanding of the population biology and evolution of Pt in the Indian subcontinent.
Abstract: Leaf or brown rust caused by Puccinia triticina (Pt) is one of the most important diseases of wheat. Among the rusts, it is the most ubiquitous in all the wheatgrowing regions and causes considerable yield loss. Microsatellite marker-based genotyping and virulence- based phenotyping of 48 pathotypes of Pt was performed. The pathotypes exhibit low virulence frequencies for Indian leaf rust differentials Lr24, Lr9, Lr10, Lr19, Lr28 and Lr9 . Using avirulence/virulence formula six major clusters of pathotypes were observed, revealing high degree of phenotypic variation. Molecular analysis performed using SSR markers showed high genetic diversity among the pathotypes, and grouped them in seven major clusters. The percentage of polymorphic loci ranged from 17.95 to 84.62, Nei's gene diversity from 0.07 to 0.32 and Shannon's information index from 0.11 to 0.47. Analysis of molecular variance revealed significantly high genetic variation within Pt population. Mantel's Z test proved low positive correlation (r = 0.28) between virulence and molecular diversity, suggesting independent nature of the duo. These findings offer valuable information for framing suitable disease management strategies through appropriate region-specific gene deployment and improve the understanding of the population biology and evolution of Pt in the Indian subcontinent.
TL;DR: The article advocates for policy intervention to promote one pond for each farm holding having an area of 2.0 ha at individual farm level or on community-sharing basis to overcome drought under climate change scenario.
Abstract: This article summarizes the utility of farm pond technology as an adaptation strategy to overcome water shortage due to several reasons, including climate change. This technology has the potential to increase availability of water for supplemental irrigation, increase in cropped area and productivity leading to increase in net returns from crops. Farm pond offers a solution to overcome the increased frequencies of drought, particularly mid-season and terminal drought under climate change scenario. The article advocates for policy intervention to promote one pond for each farm holding having an area of 2.0 ha at individual farm level or on community-sharing basis. Constraints for large-scale implementation of farm pond technology are also discussed.
TL;DR: An effort has been made to calculate the water needs for various crops in different agro-ecological units of Kollam district using FAO-CROPWAT, and infer that if the total area is brought under irrigation, there will be water scarce years, and hence decreasing irrigation or the command area needs to be adopted to manage this shortfall and sustain production.
Abstract: An effort has been made to calculate the water needs for various crops in different agro-ecological units (AEUs) of Kollam district (a humid tropical region of Kerala) using FAO-CROPWAT. The major cultivated crops are rice, coconut, rubber, pepper, banana, brinjal, tomato, tapioca, cardamom, tea, etc. The gross water required for these crops has been computed in various AEUs using meteorological parameters. Using evapotranspiration and effective rainfall in each unit, a water balance has been worked out. An overall water balance of the district has been attempted by considering irrigation, domestic and industrial demand of AEUs, under current scenario and future demand. The gross irrigation demand for the currently irrigated area in the district at 70% efficiency is 1045 mm, of which 920 mm is supplied from surface water sources and 125 mm from groundwater sources. The projected future total water demands for irrigation, drinking and industrial purposes will be 2667 mm. However, the utilizable water resource from all river basins of Kollam is only 1117 mm. The above data shows a deficit of 1550 mm and it will be difficult to arrive at requirements with the existing water resources at a given point of time. We infer that if the total area is brought under irrigation, there will be water scarce years, and hence decreasing irrigation or the command area needs to be adopted to manage this shortfall and sustain production. We have also discussed several options/strategies for better water management under these changing climatic circumstances to provide water to meet the demands of all the users.
TL;DR: This paper presents the results of a six-month study conducted at the Dadhwal National Remote Sensing Centre in Hyderabad, India, exploring the effects of radio-frequency signature analysis on the response of the human eye to radiofrequency signals.
Abstract: C. Sudhakar Reddy*, C. S. Jha, G. Manaswini, V. V. L. Padma Alekhya, S. Vazeed Pasha, K. V. Satish, P. G. Diwakar and V. K. Dadhwal National Remote Sensing Centre, Indian Space Research Organisation, Balanagar, Hyderabad 500 037, India Indian Space Research Organisation, Antariksh Bhavan, New BEL Road, Bengaluru 560 231, India Indian Institute of Space Science and Technology, Valiamala, Thiruvananthapuram 695 547, India
TL;DR: Innovation, a buzzword in the globalized world economy, predominantly refers to technological changes within the formal sector, although the genealogy of the word shows its use in ancient and medieval times with a negative connotation as discussed by the authors.
Abstract: Innovation, a buzzword in the globalized world economy, predominantly refers to technological changes within the formal sector, although the genealogy of the word shows its use in ancient and medieval times with a negative connotation. This was not an important concept until the 'Schumpeter Mark I&II' that has changed its understanding and revolutionized the field of innovation studies. Also, the agents of change in Mark I, i.e. individual innovators were replaced by firms in Mark II. However, at the turn of the 21st century, scholars and policymakers once again focused on individual innovators, especially in the informal sector in India. This book is a timely intervention in terms of highlighting the contribution of these 'unsung heroes' or the 'grassroots innovators', as termed by the author Anil Gupta.
TL;DR: Literature survey indicates that development of coloured tuberose is possible through creation of genetic variability through conscious/selective breeding and collection of coloured germplasm is the most important step in developing new flower colour tuberose through hybridization and induced in vitro mutagenesis.
Abstract: In the floriculture industry there is always demand and necessity for new and novel varieties. The colour, form and scent of the flower are the primary novelty markers in the global flower industry. Genetic diversity plays an important role in breeding. P. tuberosa is grown all over the world for cut flower production, for floriculture trade and as a source of oil. Breeding has successfully developed high yielding varieties in India, but there is no new colour. Literature survey indicates that development of coloured tuberose is possible through creation of genetic variability through conscious/selective breeding. Collection of coloured germplasm is the most important step in developing new flower colour tuberose through hybridization and induced in vitro mutagenesis.
TL;DR: In this article, a state-level analysis of sustainability was made for two time-periods, i.e. 2001 and 2011, and the results revealed that in general, sustainability did not deteriorate over the reference period, although some states gained and some others lost in terms of change in the level of sustainability.
Abstract: Sustainability of agriculture is a matter of concern for various stakeholders. The challenges encountered by Indian agriculture are due to agro-climatic/environmental, social and economic dimensions. The sustainability strength comes due to vibrancy of these dimensions. In order to understand the regional and temporal dynamics of these dimensions, a state-level analysis of sustainability was made for two time-periods. The sustainability index estimation was based on the human development index methodology. Data for two time-periods, i.e. 2001 and 2011 were used to estimate the indices. The results revealed that in general, sustainability did not deteriorate over the reference period, although some states gained and some others lost in terms of change in the level of sustainability.
TL;DR: The present review outlines several illustrations of this versatile system based on folate decorated chitosan, which have shown potential as auspicious delivery systems published over the past few years.
Abstract: Nanotechnology offers a number of nanoscale implements for medicine. Among these, nanoparticles are revolutionizing the field of drug and gene delivery. Chitosan is a natural polymer which provides a profitable tool to an innovative delivery system due to its inherent physicochemical and biological characteristics. Chitosan nanoparticles are promising drug and gene delivery carriers because of small size, better stability, low toxicity, inexpensiveness, simplicity, easy fabrication and versatile means of administration. Chitosan can also be easily modified chemically due to the presence of reactive functional hydroxide and amine groups. Folic acid is commonly engaged as a ligand, for targeting cancer cells, as its receptor, that transports folic acid into the cells through endocytosis and is over-expressed on the surface of several human epithelial cancer cells. Integrating folic acid into chitosan-based drug delivery inventions directs the systems with a well-organized targeting ability. The present review outlines several illustrations of this versatile system based on folate decorated chitosan, which have shown potential as auspicious delivery systems published over the past few years. In addition, it is probable to formulate chitosan nanocarriers that exhibit manifold usage beyond targeted delivery, such as nanotheranostics and cancer stem cell therapy.
TL;DR: In this paper, the authors present a comprehensive spatio-temporal monitoring of wetland dynamics in the lower segment of the Bagmari-Bansloi-Pagla sub-basin of the Ganga-Bhagirathi rivers using image classification technique and some fragmentation indices.
Abstract: Numerous seasonally flooded wetlands in the lower Gangetic floodplain offer unique natural habitat for many migratory bird species due to their geographical location and hydro-ecological functioning. The various developmental projects change the riverine flow regime and cause hydro-ecological modification in the Gangetic floodplain wetland system. This study presents a comprehensive spatio-temporal monitoring of wetland dynamics in the lower segment of the Bagmari-Bansloi-Pagla sub-basin of the Ganga-Bhagirathi rivers using image classification technique and some fragmentation indices. Our results reveal that the land-use conversion and fragmentation processes that affect the wetland landscape are generally represented as the evolution, and consecutive drying and squeezing of wetland patches over the study area. The water-spreading area of the wetlands was highest during 1975 after the construction of the Bhagirathi feeder canal. The situation has worsened since 1980 due to cumulative effects of agriculture after the Green revolution, and the whole landscape has become a fragmented, isolated and agronomically managed wetland.
TL;DR: In this article, the green synthesis of nitrogen-doped carbon dots (C.dots) from sesame seeds using microwave pyrolysis method was studied using transmission electron microscopy (TEM), UV/ visible spectroscopy, fluorescence spectra, and Fourier transform infra-red spectra (FTIR).
Abstract: The present study focuses on the green synthesis of nitrogen-doped carbon dots (C.dots) from sesame seeds using microwave pyrolysis method. The C.dots obtained were characterized and extensively studied using transmission electron microscopy (TEM), UV/ visible spectroscopy, fluorescence spectroscopy and Fourier transform infra-red spectroscopy (FTIR) techniques. The results indicated the presence of highly fluorescent, aqueous soluble and significantly photostable C.dots with a quantum yield of 8.02%. The average size distributions of C.dots were found to be 5 nm. These C.dots were effectively applied as a selective sensor for Fe(III) as the fluorescence intensity was significantly quenched with increasing metal concentrations. The limit of detection (LOD) was found to be 2.56 M of Fe(III). This study demonstrates a low cost, environmental friendly and waste recyclable synthetic method for preparation of C.dots and its application as a selective Fe(III) sensor.
TL;DR: In this article, a multi-collector inductively coupled plasma mass spectrometer (ICPMS) was used in combination with an Excimer (193 nm) laser to carry out in situ U-Pb dating of zircons.
Abstract: A multi-collector (MC) inductively coupled plasma mass spectrometer (ICPMS) was used in combination with an Excimer (193 nm) laser to carry out in situ U-Pb dating of zircons. High performance twovolume sample cell provided unmatched laser ablated aerosol transportation efficiency resulting in reducing laser-related down-hole fractionation. Three wellcharacterized natural zircon reference standards (Harvard zircon 91500, GJ-1 zircon, Plesovice) were repeatedly measured in different sessions to evaluate the analytical figures of merits. Precision of <1% was achieved for spot sizes 20 μm with accuracies well within 2% of the reference values for these standards. Zircons from MCT Zone in the inner Lesser Himalaya reveal a highly discordant Palaeo-proterozoic (1901 ± 11 Ma) magmatic crystallization age inferred from the upper intercept in the concordia plot. The 207 Pb/ 206 Pb ages are also internally consistent with the disconcordia age with a weighted mean of 1900 ± 10 Ma and in turn suggest a major phase of Palaeo-proterozoic magmatic activity along the northern margin of Indian craton, while Early Miocene (~25 Ma) Pb loss in zircon inferred from lower intercept in disordria may be related to tectono-thermal activity along MCT.