1,034 research outputs found

    Modelling the Encroachment of Farmhouse Culture on Private Village Pastures and Its Environmental Fall-Out in Northern Western Ghats, India

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    Tropical India harbours numerous pasturelands across small landholdings ranging up to few hectares which are covered with grass that is suitable as fodder. These grazing lands are commonly known as ‘Gairan’ in urbanised northern Western Ghats mountain tract in Western India). Such grasslands comprise about 20% of the total area of a village (Jodha, 1986), support livestock and supplement the agro-economy of the village. These pasturelands are being replaced by fenced ‘farmhouses’ of the urban elite, resulting in land use changes that caused drastic qualitative and quantitative changes in terms of area, fodder species composition and livestock they support (Patwardhan et al., 2003). The study area has faced large changes in the last few decades with increases in the area under settlement by 240%s as well as a decrease in the area of agriculture land and grasslands-scrub vegetation by 31 % and 39 % respectively (Nalavade, 2003). The present paper documents socio-cultural, economic and environmental changes in private village pastures across the Mumbai-Pune urban belt

    Evaluation of gas phase mass transfer at low reynolds numbers: a new model system

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    A new experimental system is presented which is suitable for studying gas side mass transfer coefficients in packed columns at Reynolds numbers even lower than 1.0. The system involves desorption of iodine from aqueous KI solutions. The reversible complex formation between iodine and iodine ions effectively slows down the concentration changes which otherwise would be too rapid for accurate experimentation

    RAPD Analysis for Determination of Components in Herbal Medicine

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    In this study, the RAPD (Random Amplified Polymorphic DNA) technique was employed for determination of the components in an Ayurvedic herbal prescription, Rasayana Churna. One-hundred-and-twenty decamer oligonucleotide primers were screened in the RAPD analysis to identify three Ayurvedic medicines, dried stem of Tinospora cordifolia, dried fruit of Emblica officinalis and dried fruit of Tribulus terestris, the Ayurvedic prescription. Primer OPC-6 simultaneously generated three distinct amplicons, each specific to one component. The marker with 600 bp is specific to Tinospora cordifolia; the marker 500 bp is specific to Emblica officinalis and the remaining marker >1000 bp was present in Tribulus terestris. Presence of three herbal medicines was determined when RAPD reaction with OPC-6 was performed. The technique was proved to contribute to the identification of components in Ayurvedic herbal preparation and thus helping to serve as a complementary tool for quality control

    Simulated projections for summer monsoon climate over India by a high-resolution regional climate model (PRECIS)

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    Impact of global warming on the Indian monsoon climate is examined using Hadley Centre’s highresolution regional climate model, PRECIS (Providing REgional Climates for Impact Studies). Three simulations from a 17-member Perturbed Physics Ensemble generated using Hadley Center Coupled Model (HadCM3) for the Quantifying Uncertainty in Model Predictions (QUMP) project, are used to drive PRECIS. The PRECIS simulations corresponding to the IPCCSRES A1B emission scenario are carried out for a continuous period of 1961–2098. The model shows reasonable skill in simulating the monsoon climate over India. The climate projections are examined over three time slices, viz. short (2020s, i.e. 2011–2040), medium (2050s, i.e. 2041–2070) and long (2080s, i.e. 2071–2098). The model projections indicate significant warming over India towards the end of the 21st century. The summer monsoon precipitation over India is expected to be 9–16% more in 2080s compared to the baseline (1970s, i.e. 1961–1990) under global warming conditions. Also, the rainy days are projected to be less frequent and more intense over central India

    Micro-Capsules in Shear Flow

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    This paper deals with flow-induced shape transitions of elastic capsules. The state of the art concerning both theory and experiments is briefly reviewed starting with dynamically induced small deformation of initially spherical capsules and the formation of wrinkles on polymerized membranes. Initially non-spherical capsules show tumbling and tank-treading motion in shear flow. Theoretical descriptions of the transition between these two types of motion assuming a fixed shape are at variance with the full capsule dynamics obtained numerically. To resolve the discrepancy, we expand the exact equations of motion for small deformations and find that shape changes play a dominant role. We classify the dynamical phase transitions and obtain numerical and analytical results for the phase boundaries as a function of viscosity contrast, shear and elongational flow rate. We conclude with perspectives on timedependent flow, on shear-induced unbinding from surfaces, on the role of thermal fluctuations, and on applying the concepts of stochastic thermodynamics to these systems.Comment: 34 pages, 15 figure

    Unlocking the holy grail of sustainable and scalable mesoporous silica using computational modelling

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    Bio-inspired methods offer a great alternative to design high-value mesoporous silica under more environmentally friendly conditions, allowing for an economical and sustainable scale-up. However, the synthesis of bio-inspired silica (BIS) is currently poorly understood, creating barriers to achieving products with comparable quality to traditional mesoporous silica. This perspective summarizes the key findings in the development of ordered mesoporous silica (OMS) and BIS synthesis, highlighting in particular the challenges faced in the development of scalable processing routes for these materials. Recent successes in improving mechanistic understanding of these syntheses using computational modelling are then presented, followed by suggestions as to how modelling may be used for predictive design of BIS with desired quality attributes. A multi-scale computational model, utilizing a combination of both ‘top-down’ and ‘bottom-up’ approaches, is argued to be critical for achieving a unified description of both BIS and OMS synthesis, allowing the potential of these materials to be fully realised

    Reexamining Chronic \u3cem\u3eToxoplasma gondii\u3c/em\u3e Infection: Surprising Activity for a Dormant Parasite

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    Purpose of Review Despite over a third of the world’s population being chronically infected with Toxoplasma gondii, little is known about this largely asymptomatic phase of infection. This stage is mediated in vivo by bradyzoites within tissue cysts. The absence of overt symptoms has been attributed to the dormancy of bradyzoites. In this review, we reexamine the conventional view of chronic toxoplasmosis in light of emerging evidence challenging both the nature of dormancy and the consequences of infection in the CNS. Recent Findings New and emerging data reveal a previously unrecognized level of physiological and replicative capacity of bradyzoites within tissue cysts. These findings have emerged in the context of a reexamination of the chronic infection in the brain that correlates with changes in neuronal architecture, neurochemistry, and behavior that suggest that the chronic infection is not without consequence. Summary The emerging data driven by the development of new approaches to study the progression of chronic toxoplasma infection reveals significant physiological and replicative capacity for what has been viewed as a dormant state. The emergence of bradyzoite and tissue cyst biology from what was viewed as a physiological “black box” offers exciting new areas for investigation with direct implications on the approaches to drug development targeting this drug-refractory state. In addition, new insights from studies on the neurobiology on chronic infection reveal a complex and dynamic interplay between the parasite, brain microenvironment, and the immune response that results in the detente that promotes the life-long persistence of the parasite in the host

    Cardiac Autonomic Effects of Acute Exposures to Airborne Particulates in Men and Women

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    The aim of this research was to investigate cardiac autonomic changes associated with acute exposures to airborne particulates. Methods: High fidelity 12-lead ECG (CardioSoft, Houston, TX) was acquired from 19 (10 male / 9 female) non-smoking volunteers (age 33.6 +/- 6.6 yrs) during 10 minutes pre-exposure, exposure and post-exposure to environmental tobacco smoke (ETS), cooking oil fumes, wood smoke and sham (water vapor). To control exposure levels, noise, subject activity, and temperature, all studies were conducted inside an environmental chamber. Results: The short-term fractal scaling exponent (Alpha-1) and the ratio of low frequency to high frequency Heart Rate Variability (HRV) powers (LF/HF, a purported sympathetic index) were both higher in males (p<0.017 and p<0.05, respectively) whereas approximate entropy (ApEn) and HF/(LF+HF) (a purported parasympathetic index) were both lower in males (p<0.036, and p<0.044, respectively). Compared to pre-exposure (p<0.0002) and sham exposure (p<0.047), male heart rates were elevated during early ETS post-exposure. Our data suggest that, in addition to tonic HRV gender differences, cardiac responses to some acute airborne particulates are gender related

    Designing bioinspired green nanosilicas using statistical and machine learning approaches

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    The in vitro bioinspired synthesis of silica, inspired from in vivo biosilicification, is a sustainable alternative to the conventional production of high value porous silicas. The short reaction time, mild reaction conditions of room temperature and its use of benign precursors make this an eco-friendly, economical and scalable route with great industrial potential. However, a systematic optimisation of critical process parameters and material attributes of bioinspired silica is lacking. Specifically, statistical approaches such as design of experiments (DoE) and global sensitivity analysis (GSA) using machine learning could be highly effective but have not been applied to this “green” nanomaterial yet. Herein, for the first time, a sequential DoE strategy was developed with pre-screening experiments to outline the feasible design space. A successive screening using 23 full factorial design determined that from the initially investigated three factors (the ratio of the reactant concentrations, pH, and precursor concentration), only the first two were statistically significant for silica yield and surface area. The subsequent concatenated optimisation using central composite design located a maximum yield of 90 mol% and a maximum surface area of 300–400 m2 g−1. Since for successful commercialisation, high yields and large specific surface areas are desirable, their simultaneous optimisation was also achieved with high predictability regression models. For complementation, a variance-based GSA was successfully applied to bioinspired silica for the first time. This method rapidly identified key parameters and interactions that control the physicochemical properties and provided insights in the wide parameter space, which was validated by the extensive DoE campaign. This work is the starting point in holistically modelling the multidimensional factor–response relationship over a large experimental space in order to complement efforts for resource-efficient product and process development and optimisation of bioinspired silica and beyond
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