5,527 research outputs found
Plant Growth Regulators for Mitigating Water Stress in Cowpea
Water is becoming a scarce commodity for irrigation especially under the present changing climatic scenario. Water stress hampers important physiological and biochemical mechanisms leading to reduction in plant growth and yield. Studies revealed that the exogenous application of plant hormones has been found to alleviate the negative effects of various abiotic stresses. Cowpea, being a non-season bound crop, can be grown throughout the year and it performs well during summer season under irrigation, but water scarcity limits its area under cultivation. However, limited research works have been conducted to investigate the potential benefits of exogenous application of plant growth regulators (PGRs) in cowpea grown under water stress conditions. So the present study was undertaken to evaluate the efficacy of exogenous application of certain plant growth regulators to mitigate water stress in cowpea, to find out an effective plant growth regulator for drought management and to assess the response of cowpea to these plant growth regulators
Seed Hardening and Moisture Conservation Practices to Mitigate Water Stress in Cowpea
Cowpea is an important protein catering feed/fodder for cattle. Being a non-season bound crop, it can be grown throughout the year and performs well during summer season under irrigation but water scarcity limits its area under cultivation. It necessitates the development of alternate management technologies to overcome the water stress period for the sustainable growth and yield of the crop. Seed hardening, soil moisture conservation measures like mulching and antitranspirant sprays are the techniques which helps the plant to survive under drought. So the present study was undertaken to evaluate the efficacy of various seed primers, antitranspirants and mulches for mitigating water stress in cowpea grown during summer season, to find out the best among each and also to assess the response of cowpea to these techniques under water stress conditions
Small-scale traditional spiny lobster fishery at Tikkoti, Calicut
The spiny lobster fishery at Tikkoti though lesser in magnitude is important from the fishery point of view. The traditional fishermen living in three adjacent villages of Kodikal, Kadaloor and Tikkoti are engaged in lobster fishing for the past five decades. The total landings have declined over the years but sudden fall in catches as is seen in 1996-'97 may probably due to natural fluctuations in environmental conditions and change in current pattern rather than due to over fishing. In 1960's fishing was restricted to only three months from August to October and now the fishing begins in September or October and continues up to April or May. Unlike the southwest and southeast coasts where lobster fishing activity has increased several fold due to pressure from the export market, there is no substantial increase in effort at Tikkoti. Establishment of artificial reefs may help in enhancement of lobster population and therefore increase in catches and more revenue for the fishermen
A Global Modeling Study on Carbonaceous Aerosol Microphysical Characteristics and Radiative Effects
Recently, attention has been drawn towards black carbon aerosols as a short-term climate warming mitigation candidate. However the global and regional impacts of the direct, indirect and semi-direct aerosol effects are highly uncertain, due to the complex nature of aerosol evolution and the way that mixed, aged aerosols interact with clouds and radiation. A detailed aerosol microphysical scheme, MATRIX, embedded within the GISS climate model is used in this study to present a quantitative assessment of the impact of microphysical processes involving black carbon, such as emission size distributions and optical properties on aerosol cloud activation and radiative effects. Our best estimate for net direct and indirect aerosol radiative flux change between 1750 and 2000 is -0.56 W/m2. However, the direct and indirect aerosol effects are quite sensitive to the black and organic carbon size distribution and consequential mixing state. The net radiative flux change can vary between -0.32 to -0.75 W/m2 depending on these carbonaceous particle properties at emission. Taking into account internally mixed black carbon particles let us simulate correct aerosol absorption. Absorption of black carbon aerosols is amplified by sulfate and nitrate coatings and, even more strongly, by organic coatings. Black carbon mitigation scenarios generally showed reduced radiative fluxeswhen sources with a large proportion of black carbon, such as diesel, are reduced; however reducing sources with a larger organic carbon component as well, such as bio-fuels, does not necessarily lead to a reduction in positive radiative flux
Ignition and chemical kinetics of acrolein-oxygen-argon mixtures behind reflected shock waves
In order to address increasing greenhouse gas emissions, the future fossil fuel shortage and increasingly stringent pollutant emission regulations, a variety of biofuels are being progressively incorporated into conventional transportation fuels. Despite the beneficial impact of biofuels on most regulated pollutants, their combustion induces the increase of a variety of aldehydes that are being considered for specific regulations due to their high toxicity. One of the most hazardous aldehyde compounds is acrolein, C_2H_3CHO. Despite its high toxicity and increased formation during bioalcohol and biodiesel combustion, no experimental data are available for acrolein combustion. In the present study, we have investigated the ignition of acrolein–oxygen–argon mixtures behind reflected shock wave using three simultaneous emission diagnostics monitoring OH∗, CH∗ and CO_2∗. Experiments were performed over a range of conditions: Φ = 0.5–2; T_5 = 1178–1602 K; and P_5 = 173–416 kPa. A tentative detailed reaction model, which includes sub-mechanisms for the three measured excited species, was developed to describe the high-temperature chemical kinetics of acrolein oxidation. Reasonable agreement was found between the model prediction and experimental data
Distribution, abundance and biology of unicorn cod, Bregmaceros mcclellandi in the deep scattering layers of Indian Exclusive Economic Zone
In the deep scattering layer (DSL) the fishes have accounted for 5.4 % of the
total (numerical) biomass. Juvenile fish belonging to different families were the most
abundant component followed by Vinciguerria, myctophids, leptocephali, stomiforms,
and unicorn cod. The "unicorn cod is represented by a single species,
Bregmaceros mcclellandi (2.4%) in the total fish biomass. It occurred in 52 stations
out of 445 IKMT stations. During day time the average number per haul was 21 where
as in night hauls it was 29. The resource was fairly abundant along the northwest coast
within the depth belt of 200 m. Biological studies on the size composition, feeding
habits, and reproductive biology of the species were also carried out. The length
ranged from 10-65 mm. The major diet consists of copepods, euphausiids, cheatognaths,
ostracods and decapod larvae. Invariably the feeding intensity was low. The
catch was composed of mostly females in maturity stages IV-V. The species spawns
only once in a year. The fecundity ranged from 530 - 980 in fishes of 42 - 50 mm in
total length
The Glass Transition and Liquid-Gas Spinodal Boundaries of Metastable Liquids
A liquid can exist under conditions of thermodynamic stability or
metastability within boundaries defined by the liquid-gas spinodal and the
glass transition line. The relationship between these boundaries has been
investigated previously using computer simulations, the energy landscape
formalism, and simplified model calculations. We calculate these stability
boundaries semi-analytically for a model glass forming liquid, employing
accurate liquid state theory and a first-principles approach to the glass
transition. These boundaries intersect at a finite temperature, consistent with
previous simulation-based studies.Comment: Minor text revisions. Fig.s 4, 5 update
Socioeconomic indicators of health inequalities and female mortality: a nested cohort study within the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS)
Evidence is mounting that area-level socioeconomic indicators are important tools for predicting health outcomes. However, few studies have examined these alongside individual-level education. This nested cohort study within the control arm of the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) assesses the association of mutually adjusted individual (education) and area-level (Index of Multiple Deprivation-IMD 2007) socioeconomic status indicators and all-cause female mortality
A Coupled Map Lattice Model for Rheological Chaos in Sheared Nematic Liquid Crystals
A variety of complex fluids under shear exhibit complex spatio-temporal
behaviour, including what is now termed rheological chaos, at moderate values
of the shear rate. Such chaos associated with rheological response occurs in
regimes where the Reynolds number is very small. It must thus arise as a
consequence of the coupling of the flow to internal structural variables
describing the local state of the fluid. We propose a coupled map lattice (CML)
model for such complex spatio-temporal behaviour in a passively sheared nematic
liquid crystal, using local maps constructed so as to accurately describe the
spatially homogeneous case. Such local maps are coupled diffusively to nearest
and next nearest neighbours to mimic the effects of spatial gradients in the
underlying equations of motion. We investigate the dynamical steady states
obtained as parameters in the map and the strength of the spatial coupling are
varied, studying local temporal properties at a single site as well as
spatio-temporal features of the extended system. Our methods reproduce the full
range of spatio-temporal behaviour seen in earlier one-dimensional studies
based on partial differential equations. We report results for both the one and
two-dimensional cases, showing that spatial coupling favours uniform or
periodically time-varying states, as intuitively expected. We demonstrate and
characterize regimes of spatio-temporal intermittency out of which chaos
develops. Our work suggests that such simplified lattice representations of the
spatio-temporal dynamics of complex fluids under shear may provide useful
insights as well as fast and numerically tractable alternatives to continuum
representations.Comment: 32 pages, single column, 20 figure
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