3,412 research outputs found

    Why some community forests are performing better than others: a case of forest user groups in Nepal

    Get PDF
    Management of many Nepalese forests has been devolved to local communities. Forest products, which are used by the community and which may also be traded, are essential contributors to community well-being. Forests are also important contributors of ecosystem services, such as flood protection and wildlife habitat. Nepalese communities were surveyed to measure flows of forest products from their community forests. A stochastic frontier analysis shows that communities are not producing forest products efficiently and there is potential for improvement. The results shows that forest products benefit and environmental performance are associated products. In addition, analysis reveals that factors such as social capital, support from government and knowledge in management contributes positively to the production efficiency. It is anticipated that these findings will contribute to community forest policy redesign and consequently to the welfare of communities.Community forestry, stochastic frontier, production efficiency, Nepal, Community/Rural/Urban Development, Environmental Economics and Policy, Farm Management, Productivity Analysis,

    What is India speaking? Exploring the "Hinglish" invasion

    Get PDF
    © 2016 Elsevier B.V. All rights reserved. Language competition models help understand language shift dynamics, and have effectively captured how English has outcompeted various local languages, such as Scottish Gaelic in Scotland, and Mandarin in Singapore. India, with a 125 million English speakers boasts the second largest number of English speakers in the world, after the United States. The 1961-2001 Indian censuses report a sharp increase in Hindi/English Bilinguals, suggesting that English is on the rise in India. To the contrary, we claim supported by field evidence, that these statistics are inaccurate, ignoring an emerging class who do not have full bilingual competence and switch between Hindi and English, communicating via a code popularly known as "Hinglish". Since current language competition models oc clude hybrid practices and detailed local ecological factors, they are inappropriate to capture the current language dynamics in India. Expanding predator-prey and sociolinguistic theories, we draw on local Indian ecological factors to develop a novel three-species model of interaction between Monolingual Hindi speakers, Hindi/English Bilinguals and Hinglish speakers, and explore the long time dynamics it predicts. The model also exhibits Turing instability, which is the first pattern formation result in language dynamics. These results challenge traditional assumptions of English encroachment in India. More broadly, the three-species model introduced here is a first step towards modeling the dynamics of hybrid language scenarios in other settings across the world

    Prompt emission polarimetry of Gamma Ray Bursts with ASTROSAT CZT-Imager

    Full text link
    X-ray and Gamma-ray polarization measurements of the prompt emission of Gamma-ray bursts (GRBs) are believed to be extremely important for testing various models of GRBs. So far, the available measurements of hard X-ray polarization of GRB prompt emission have not significantly constrained the GRB models, particularly because of the difficulty of measuring polarization in these bands. The CZT Imager (CZTI) onboard {\em AstroSat} is primarily an X-ray spectroscopic instrument that also works as a wide angle GRB monitor due to the transparency of its support structure above 100 keV. It also has experimentally verified polarization measurement capability in the 100 - 300 keV energy range and thus provides a unique opportunity to attempt spectro-polarimetric studies of GRBs. Here we present the polarization data for the brightest 11 GRBs detected by CZTI during its first year of operation. Among these, 5 GRBs show polarization signatures with \gtrapprox3σ\sigma, and 1 GRB shows \>2σ\sigma detection significance. We place upper limits for the remaining 5 GRBs. We provide details of the various tests performed to validate our polarization measurements. While it is difficult yet to discriminate between various emission models with the current sample alone, the large number of polarization measurements CZTI expects to gather in its minimum lifetime of five years should help to significantly improve our understanding of the prompt emission.Comment: Accepted for Publication in ApJ ; a figure has been update

    Prediction and management of natural disasters through indigenous Technical Knowledge, with special reference to fisheries

    Get PDF
    Traditional Indigenous knowledge has over the years played a significant role in solving several major social-ecological problems including those related to climate change and variability. People living close to nature often observe the circumstances around them and are the often the first to identify and adapt to any changes. The appearance of certain birds, mating of certain animals and flowering of certain plants are all seen as important signals of change with respect to timing and seasonality of natural phenomena that are well understood in traditional knowledge systems. Indigenous and local peoples have relied on biodiversity as a buffer against environmental variation, change and catastrophe

    Single-Pot Rapid Synthesis of Colloidal Core/Core-Shell Quantum Dots: A Novel Polymer-Nanocrystal Hybrid Material

    Get PDF
    Colloidal core and core shell Quantum Dots (QD's) are unique and important optoelectronic materials because properties of these QD's can be tailored by configuring core and optimizing shell thickness. In this research work, lead selenide (PbSe) core and PbSe-CdSe (Core-shell) QD's are synthesized using oleic acid as a capping ligand by colloidal route. This simpler, cost-effective and rapid single pot synthesis route for colloidal core-shell quantum dots unlike conventional double-pot approach like cation-exchange and SILAR process has been reported for the very first time. Phase formation of prepared quantum dots is confirmed by XRD analysis, capping ligand presence by IR spectroscopy and morphological information by Scanning electron microscopy respectively. These synthesized inorganic quantum dots are dispersed in Poly (3-hexyl thiophene) polymer for formation of their respective nanocomposites. From PL quenching studies, it was inferred that PbSe-CdSe core-shell quantum dots showed enhanced rate of PL quenching and hence higher value of Stern-Volmer constant (K-SV) than PbSe Core QD's. This confirms that CdSe shell formation on PbSe core significantly passivates the core-surface, increases the stability and enhances the charge transfer mechanism for its potential application in Hybrid Solar cells

    The use of OH "main" lines to constrain the variation of fundamental constants

    Get PDF
    We describe a new technique to measure variations in the fundamental parameters α\alpha and yme/mpy \equiv m_e/m_p, using the sum of the frequencies of cm-wave OH ``main'' lines. The technique is \sim three orders of magnitude more sensitive than that of Chengalur & Kanekar (2003), which utilised only the four 18cm OH lines. The increase in sensitivity stems from the use of OH ``main'' lines arising from different rotational states, instead of the frequency difference between lines from the same state. We also show that redshifts of the main OH 18cm and 6cm lines can be combined with the redshift of an HCO+^+ transition to measure any evolution in α\alpha and yy. Both 18cm main lines and a number of HCO+^+ lines have already been detected in absorption in four cosmologically distant systems; the detection of the main 6cm OH line in any of these systems would thus be sufficient to simultaneously constrain changes in α\alpha and yy between the absorption redshift and today.Comment: 5 pages, no figures. MNRAS (Letters), in pres

    Ferromagnetism and ferroelectricity in highly resistive Pb(0.7)Sr(0.3)(Fe(0.012)Ti(0.988))O(3) nanoparticles and its conduction by variable-range-hopping mechanism

    Get PDF
    The enhancement in ferromagnetism and ferroelectricity at room temperature for Pb0.7Sr0.3�Fe0.012Ti0.988�O3 �PSFT� nanoparticles is proved by magnetization and polarization hysteresis loop. The x-ray diffraction and micrograph show that the PSFT nanoparticles have distorted tetragonal single phase, and their average particle’s size is 8 nm. The effect of Sr content reduces the particle size, and hence the multiferroic system becomes more resistive, which dominates the superparamagnetic/paraelectric relaxation. The variable-range-hopping conduction mechanism explained the high resistivity of PSFT nanoparticles, which suggests that the room temperature movement of electrons involves short-range order through defect states
    corecore