864 research outputs found
Trends, Determinants and Constraints of Temporary Sheep Migration in Rajasthan ĂąâŹâ An Economic Analysis
The study has analysed the temporary migration of sheep as a response to the demand-supply disequilibrium of fodder and water and has explored its trends, determinants and constraints by using the data collected from rural areas of semi-arid Rajasthan. About 32 per cent of the farmers in the study area undertake temporary sheep migration. The migrating farmers have higher holding size of sheep, goat and buffaloes and are better in terms of adoption of improved sheep management practices than non-migrant farmers. The flock size, potential household labour supply and credit absorption behaviour have been reported to positively affect the odds of migration. The farmers face various en-route problems during migration, the major ones being increased morbidity, non-availability of veterinary medicines, resistance from local persons, theft and missing of sheep. The net return per animal per year has been found slightly higher in case of the non-migrant sheep flocks. The study has argued that migration of livestock is to be viewed as a method of production and adaptive mechanism evolved over the years. Efforts to sendentarise migrants without providing alternate fodder sources or productive assets of gainful employment may not be fruitful. In order to sustain the livelihood of the sheep farmers, institutional intervention to enhance accessibility to fodder and feed, veterinary services and strengthening of the extension services is needed.Sheep migration, Rajasthan, Sheep farming, Agricultural and Food Policy, Q11,
Returns and Economic Efficiency of Sheep Farming in Semi-arid Regions: A Study in Rajasthan
The economics of sheep-farming and its economic efficiency have been reported using field level data collected from the semi-arid regions of Rajasthan in 2005. The net return per average flock of 54 has been found Rs 25000 per year. The sheep-farming activity attracts labour employment of 581 mandays per annum, more than three-fourths of which is engaged in grazing. The female labour has been found to contribute 12 per cent of the total labour requirement. The main items of expenditure are feed and fodder, veterinary care, hired labour charges and interest. The major modes of return are sale of live-animals, wool, milk and manure. The overall average economic efficiency has been found to be 75 per cent, indicating that the returns could be improved by another 25 per cent with the present resource-use level. More than two-thirds of the farmers have been recorded distributed in the economic efficiency range of 70-85 per cent. The resource-poor farmers have been observed to realize higher economic efficiency than their rich counterparts. The major factor responsible for inducing improvement in efficiency has been identified as membership in farmersâ organisations, which probably provides them better access to technical knowledge and improves their bargaining power.Livestock Production/Industries,
Degradation of Common Pastures: An Economics Perspective of its Impact on Livestock Farming and Coping Strategies
The study has examined the farmersâ perception regarding deterioration of pasturelands, its impact on livestock farming and the factors affecting farmersâ willingness to contribute to a participatory pasture development programme. It is based on the primary data collected from sheep farmers of semi-arid and arid regions of Rajasthan in the year 2008. A large proportion of farmers have perceived deterioration of the pastureland which has resulted in the reductions of wool yield per animal (18%), body weight of sheep (20%) and age of disposal of lambs (45%). The major coping mechanisms adopted by the farmers have been identified are: reduction in total livestock holding (86%), reduction in sheep flock size (55%), grazing on alternative fodder sources (30%), increased frequency of migration (59%), increased duration of migration (41%), and disposal of male lambs at an early age (76%). The reduction of pastureland has resulted in cost escalation for sheep farming, particularly for the landless and small farmers. Double Bounded Dichotomous Choice (DBDC) method of Willingness to Pay (WTP) has been used to analyze the factors affecting the association of farmers with a participatory pasture development programme. The bivariate probit model estimated using this data has indicated that the expected cost and the concerns regarding inequitable distribution of benefits affect WTP negatively, whereas flock size affects it positively. The farmers in the arid region have been found more forthcoming towards a participatory management strategy. The study has highlighted the importance of awareness generation about the participatory management strategy and its incorporation as a component of livestock development programmes.Agricultural and Food Policy,
Propagators and WKB-exactness in the plane wave limit of AdSxS
Green functions for the scalar, spinor and vector fields in a plane wave
geometry arising as a Penrose limit of are obtained. The
Schwinger-DeWitt technique directly gives the results in the plane wave
background, which turns out to be WKB-exact. Therefore the structural
similarity with flat space results is unveiled. In addition, based on the local
character of the Penrose limit, it is claimed that for getting the correct
propagators in the limit one can rely on the first terms of the direct geodesic
contribution in the Schwinger-DeWitt expansion of the original propagators .
This is explicitly shown for the Einstein Static Universe, which has the same
Penrose limit as with equal radii, and for a number of other
illustrative cases.Comment: 18 pages, late
Tendency to Maximum Complexity in a Non-Equilibrium Isolated System
The time evolution equations of a simplified isolated ideal gas, the
"tetrahe- dral" gas, are derived. The dynamical behavior of the LMC complexity
[R. Lopez-Ruiz, H. L. Mancini, and X. Calbet, Phys. Lett. A 209, 321 (1995)] is
studied in this system. In general, it is shown that the complexity remains
within the bounds of minimum and maximum complexity. We find that there are
certain restrictions when the isolated "tetrahedral" gas evolves towards
equilibrium. In addition to the well-known increase in entropy, the quantity
called disequilibrium decreases monotonically with time. Furthermore, the
trajectories of the system in phase space approach the maximum complexity.Comment: 22 pages, 0 figures. Published in Phys. Rev. E 63, 066116(9) (2001
Local Hidden Variables Underpinning of Entanglement and Teleportation
Entangled states whose Wigner functions are non-negative may be viewed as
being accounted for by local hidden variables (LHV). Recently, there were
studies of Bell's inequality violation (BIQV) for such states in conjunction
with the well known theorem of Bell that precludes BIQV for theories that have
LHV underpinning. We extend these studies to teleportation which is also based
on entanglement. We investigate if, to what extent, and under what conditions
may teleportation be accounted for via LHV theory. Our study allows us to
expose the role of various quantum requirements. These are, e.g., the
uncertainty relation among non-commuting operators, and the no-cloning theorem
which forces the complete elimination of the teleported state at its initial
port.Comment: 24 pages, 1 figure, accepted Found. Phy
Quantum Locality
It is argued that while quantum mechanics contains nonlocal or entangled
states, the instantaneous or nonlocal influences sometimes thought to be
present due to violations of Bell inequalities in fact arise from mistaken
attempts to apply classical concepts and introduce probabilities in a manner
inconsistent with the Hilbert space structure of standard quantum mechanics.
Instead, Einstein locality is a valid quantum principle: objective properties
of individual quantum systems do not change when something is done to another
noninteracting system. There is no reason to suspect any conflict between
quantum theory and special relativity.Comment: Introduction has been revised, references added, minor corrections
elsewhere. To appear in Foundations of Physic
Replication of Influenza A and B Viruses in Human Diploid Cells
ArtĂculo cientĂfico -- Universidad de Costa Rica, Instituto de Investigaciones en Salud.1983Under optimal conditions, of high multiplicities of infection and with trypsin
included in the medium throughout the incubation period, high yields of infectious
influenza A and B viruses (106-5 p.f.u./ml) and of antigenically active haemagglutinin
(HA) (1 ug/HA/106 cells) were produced in human diploid MRC-5 cells. Budding virus
particles were seen as spherical or short rod-like protrusions on the surface of the
infected cells, and also on cell filopodia. Virus-induced cytoplasmic and nuclear
inclusions were present in infected cells. This virusâhuman cell system may be suitable
for studies of influenza virus persistence and for production of immunologically active
HA antigen.Universidad de Costa Rica, Instituto de Investigaciones en SaludUCR::VicerrectorĂa de InvestigaciĂłn::Unidades de InvestigaciĂłn::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA
Dust detection by the wave instrument on STEREO: nanoparticles picked up by the solar wind?
The STEREO/WAVES instrument has detected a very large number of intense
voltage pulses. We suggest that these events are produced by impact ionisation
of nanoparticles striking the spacecraft at a velocity of the order of
magnitude of the solar wind speed. Nanoparticles, which are half-way between
micron-sized dust and atomic ions, have such a large charge-to-mass ratio that
the electric field induced by the solar wind magnetic field accelerates them
very efficiently. Since the voltage produced by dust impacts increases very
fast with speed, such nanoparticles produce signals as high as do much larger
grains of smaller speeds. The flux of 10-nm radius grains inferred in this way
is compatible with the interplanetary dust flux model. The present results may
represent the first detection of fast nanoparticles in interplanetary space
near Earth orbit.Comment: In press in Solar Physics, 13 pages, 5 figure
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