2,224 research outputs found
Soil Invertebrates of \u3cem\u3eLasiurus sindicus\u3c/em\u3e Based Grazing Lands: Impact of Management and Grazing Intensity
Arid Western plains of India are dominated by pasture and grazing lands. Lasiurus sindicus (LS) is the dominant na-tive grass species growing on sandy plains and low dunes under the low rainfall extreme desert climate. Palatability and higher crude protein (8-14% in early vegetative growth, 4-6% in 80-120 days of growth) make this grass a highly preferred grazing species. Since drought is frequent (47%) in this part of the country the LS grasslands are under tremendous grazing pressures and classified under poor or very poor condition for livestock. It is imperative to re-store the natural resources on which this grassland depends.
Soil invertebrates especially soil collembola and mites are an integral part of this grassland ecosystem. Their community structure changes in response to the changes in management and other factors, and may serve as a tool for rapid impact assessment of restoration measures. With this background, Lasiurus sindicus grazing lands in Jaisalmer District of Western Rajasthan of India were evaluated, to understand the impact of grazing intensity and management practices on the community structure of the soil invertebrates
Enhanced Room Temperature Coefficient of Resistance and Magneto-resistance of Ag-added La0.7Ca0.3-xBaxMnO3 Composites
In this paper we report an enhanced temperature coefficient of resistance
(TCR) close to room temperature in La0.7Ca0.3-xBaxMnO3 + Agy (x = 0.10, 0.15
and y = 0.0 to 0.40) (LCBMO+Ag) composite manganites. The observed enhancement
of TCR is attributed to the grain growth and opening of new conducting channels
in the composites. Ag addition has also been found to enhance intra-granular
magneto-resistance. Inter-granular MR, however, is seen to decrease with Ag
addition. The enhanced TCR and MR at / near room temperature open up the
possibility of the use of such materials as infrared bolometric and magnetic
field sensors respectively.Comment: 22 pages of Text +
Figs:comments/suggestions([email protected]
Young Stellar Population of the Bright-Rimmed Clouds BRC 5, BRC 7 and BRC 39
Bright-rimmed clouds (BRCs), illuminated and shaped by nearby OB stars, are
potential sites of recent/ongoing star formation. Here we present an optical
and infrared photometric study of three BRCs: BRC 5, BRC 7 and BRC 39 to obtain
a census of the young stellar population, thereby inferring the star formation
scenario, in these regions. In each BRC, the Class I sources are found to be
located mostly near the bright rim or inside the cloud, whereas the Class II
sources are preferentially outside, with younger sources closer to the rim.
This provides strong support to sequential star formation triggered by
radiation driven implosion due to the UV radiation. Moreover, each BRC contains
a small group of young stars being revealed at its head, as the next-generation
stars. In particular, the young stars at the heads of BRC 5 and BRC 7 are found
to be intermediate/high mass stars, which, under proper conditions, may
themselves trigger further star birth, thereby propagating star formation out
to long distances.Comment: 30 pages, 7 Figures, 6 Tables, accepted for publication in Monthly
Notices of the Royal Astronomical Societ
The impact of lean practices on operational performance - an empirical investigation of Indian process industries
In deciding to adopt lean manufacturing, it is imperative to investigate where and how lean practices are most needed to influence manufacturing and business performance. Such an investigation becomes indispensable when lean thinking is to be considered in a production arrangement different to the conventional, repetitive, high-volume, stable-demand and discrete-manufacturing environment. This study provides explanations of how performance is improved through the adoption of lean practices in process industries. This is a relatively under-researched area compared to the performance effects associated with the introduction and implementation of lean principles in traditional, discrete manufacturing. Based on a survey of Indian process industries, this study attempts to develop an empirical relationship between lean practices and performance improvement through the use of multivariate statistical analysis. The findings have led to the conclusion that lean practices are positively associated with timely deliveries, productivity, first-pass yield, elimination of waste, reduction in inventory, reduction in costs, reduction in defects and improved demand management. However, within a process-industry context, lean practices related to pull production were found to have a marginal impact on performance improvement. A detailed discussion of the findings along with their theoretical and managerial implications is provided in the paper
Wheat yield forecast using detrended yield over a sub-humid climatic environment in five districts of Uttar Pradesh, India
A study was carried out to forecast the yield of the wheat crop for five districts of Uttar Pradesh namely Lucknow, Kanpur, Banda, Jhansi and Faizabad. The daily weather data on variables such as maximum temperature, rainfall, minimum temperature, and relative humidity were arranged week wise from sowing to harvesting and the relations between the weather variables and yield was worked out using statistical tools like correlation and regression. The yield has been detrended by obtaining the parameter estimates of the model and subsequently the detrended yield was used to forecast the yield of the crop using ARIMA model. The proposed method of obtaining pre-harvest forecasting of yield of crops was compared with the traditional approaches of forecasting and the proposed method was evaluated in terms of criteria’s such as goodness of fit of the model. It was observed that in all the districts the proposed model performed better as compared to the traditional method both in terms of goodness of fit as well as forecasting performance. Thus it can be concluded that the proposed approach is better and more suitable as compared to the traditional approach for forecasting the wheat yield in the five districts of Uttar Pradesh
Genomic variation and biogeography of Antarctic haloarchaea
© 2018 The Author(s). Background: The genomes of halophilic archaea (haloarchaea) often comprise multiple replicons. Genomic variation in haloarchaea has been linked to viral infection pressure and, in the case of Antarctic communities, can be caused by intergenera gene exchange. To expand understanding of genome variation and biogeography of Antarctic haloarchaea, here we assessed genomic variation between two strains of Halorubrum lacusprofundi that were isolated from Antarctic hypersaline lakes from different regions (Vestfold Hills and Rauer Islands). To assess variation in haloarchaeal populations, including the presence of genomic islands, metagenomes from six hypersaline Antarctic lakes were characterised. Results: The sequence of the largest replicon of each Hrr. lacusprofundi strain (primary replicon) was highly conserved, while each of the strains' two smaller replicons (secondary replicons) were highly variable. Intergenera gene exchange was identified, including the sharing of a type I-B CRISPR system. Evaluation of infectivity of an Antarctic halovirus provided experimental evidence for the differential susceptibility of the strains, bolstering inferences that strain variation is important for modulating interactions with viruses. A relationship was found between genomic structuring and the location of variation within replicons and genomic islands, demonstrating that the way in which haloarchaea accommodate genomic variability relates to replicon structuring. Metagenome read and contig mapping and clustering and scaling analyses demonstrated biogeographical patterning of variation consistent with environment and distance effects. The metagenome data also demonstrated that specific haloarchaeal species dominated the hypersaline systems indicating they are endemic to Antarctica. Conclusion: The study describes how genomic variation manifests in Antarctic-lake haloarchaeal communities and provides the basis for future assessments of Antarctic regional and global biogeography of haloarchaea
First results of evaporation residue cross-section measurements of S+Pb system
The dynamics of heavy ion-induced reactions play a critical role in forming
super heavy elements (SHE), and one clear signature of the SHE formation is the
evaporation residue (ER). In our pursuit of SHE, we present the heaviest
element populated in India for ER cross-section measurements. These are the
first-ever measurements of the Evaporation Residue (ER) cross-sections for the
nuclear reactions between S and Pb. These measurements were
conducted above the Coulomb barrier at four distinct beam energies in the
laboratory frame, ranging from 176 to 191 MeV at the pelletron Linac facility
at the Inter-University Accelerator Centre (IUAC), New Delhi. The Hybrid Recoil
Mass Analyzer (HYRA) in a gas-filled mode was employed for these experiments.
The obtained range of ER cross-sections enriches our knowledge and helps
advance the field of heavy ion-induced reactions, especially in the context of
super heavy element formation.Comment: 12 pages, 10 figures. arXiv admin note: text overlap with
arXiv:2311.0904
Measurements of evaporation residue cross-sections and evaporation residue-gated -ray fold distributions for S+Sm system
Evaporation Residue (ER) cross-sections and ER-gated -ray fold
distributions are measured for the S + Sm nuclear reaction above
the Coulomb barrier at six different beam energies from 148 to 191 MeV.
-ray multiplicities and spin distributions are extracted from the
ER-gated fold distributions. The ER cross-sections measured in the present work
are found to be much higher than what was reported in a previous work using a
very different target-projectile (Ti + Ba) combination, leading
to the same compound nucleus Pt, with much less mass asymmetry in the
entrance channel than the present reaction. This clearly demonstrates the
effect of the entrance channel on ER production cross-section. The ER
cross-sections measured in the present work are compared with the results of
both the statistical model calculations and the dynamical model calculations.
Statistical model calculations have been performed to generate a range of
parameter space for both the barrier height and Kramers' viscosity parameter
over which the ER cross-section data can be reproduced. The calculations
performed using the dinuclear system (DNS) model reproduce the data considering
both complete and incomplete fusion processes. DNS calculations indicate the
need for the inclusion of incomplete fusion channel at higher energies to
reproduce the ER cross-sections.Comment: 13 pages, 18 figure
Forecasting of crop yield using weather parameters–two step nonlinear regression model approach
Concept of the paper is firstly to remove the trend of crop yield and then to develop the forecasting models using
detrended yield. Not much work is available or development of forecast models or modelling due to their non-linear
behaviour. For that, in this paper, methodology developed for forecasting using nonlinear growth models, which
will help in forecasting yield, pest and disease incidences etc with high accuracy. Crop yield forecast models for
wheat crop have been developed (using non-linear growth models, linear models and weather indices approach with
weekly weather data) for different districts of Uttar Pradesh (UP). Weather Indices (WI) were obtained using above
two approaches. Weather indices based regression models were developed using weather indices as independent
variables while character under study such as crop yield was used as dependent variable for wheat crop, i.e. two step
non-linear forecast model. Technique of forecasting using non-linear approach and using weather indices will enrich
the knowledge in developing customized models on forecasting for different types of crops and for different locations.
The approach provided reliable yield forecast about two months before harvest
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