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Drought is a major abiotic stress worldwide limiting chickpea yield drastically. Low heritability and high genotype × environment interactions make the trait-based breeding strategy an unreliable approach. This study was planned to identify the drought-tolerant lines by evaluating yield-based selection indices in a recombinant inbred line (RIL) population derived from an inter-specific cross between drought-tolerant genotype GPF 2 (Cicer arietinum L.) and drought-sensitive accession ILWC 292 (C. reticulatum) at two locations in India (Ludhiana and Faridkot). A total of six yield-based selection indices were calculated and significant variation was observed in the RILs and their parents for yield-based selection indices at both locations. A holistic approach across association analysis and principal component analysis identified drought tolerance index, mean productivity, geometric mean productivity and harmonic mean productivity as key selection indices, which could be used for indirect selection of drought-tolerant lines. Overall, on the basis of these approaches, a total of 15 promising RILs were identified for their use in chickpea breeding programme for developing drought-tolerant cultivars.
A circularly polarized ring cylindrical dielectric resonator antenna (ring-CDRA) of wideband impedance bandwidth is presented in this article. The proposed ring CDRA consist of an inverted rectangular (tilted rectangular) shaped aperture and inverted L-shaped slotted microstrip feed line. The tilted rectangular shaped aperture and inverted L-shaped microstrip feed line generate two-hybrid mode HEM11δ and HEM12δ while ring CDRA and slotted microstrip feed line are used for the enhancement of impedance bandwidth. The proposed ring CDRA is resonating between 6.08 and 12.2 GHz with 66.95% (6120 MHz) impedance bandwidth. The axial ratio (AR) bandwidth of 6.99% (780 MHz) is obtained between 10.76 and 11.54 GHz with a minimum AR value of 0.2 dB at a frequency of 11 GHz. The proposed geometry of ring CDRA has been validated with measurement performed by VNA and anechoic chamber. The operating range of the proposed radiator is useful for different applications in X-band.
Jamming of synthetic aperture radar (SAR) is more difficult than the conventional radars because of its high processing gain. The defocusing of fake or virtual scatterers is the main problem that any jamming technique needs to tackle. An algorithm based on fractional Fourier transform is proposed for the efficient jamming of SAR. The results show that the performance of proposed algorithm is better than conventional Range Doppler Algorithm.
In this paper, the authors have presented a paraxial theory for propagation of (1) Gaussian (2) dark hollow Gaussian high power laser beams in the atmosphere, considering the nonlinearity arising from the temperature variation along the wave-front. Specifically, the focusing parameter for both beams has been evaluated as a function of distance and initial beam power and width (corresponding to radiation of wavelengths 1.045 µ, 1.625 µ, and 2.141 µ in the water absorption window) for the maritime, desert, rural, and urban environments as modeled at NRL; the results have been presented in the dimensionless form. It is seen that in all four environments a dark hollow beam defocuses less than the corresponding Gaussian beam of same radius and power. It is suggested that this conclusion based on the paraxial theory be verified by numerical simulation.
The aim of the present study was to determine the impact of universal salt iodization (USI) on the prevalence of iodine deficiency in the population of an area previously known to have severe iodine deficiency in India.
Design
In a cross-sectional survey, a total of 2860 subjects residing in fifty-three villages of four sub-districts of Gonda District were examined for goitre and urinary iodine concentration. Free thyroxine and thyroid-stimulating hormone levels were also measured. Salt samples from households were collected for estimation of iodine content.
Results
A reduction in goitre prevalence was observed from 69 % reported in 1982 to 27·7 % assessed in 2007. However, 34 % of villages still had very high endemicity of goitre (goitre prevalence >30 %). Twenty-three per cent of households consumed a negligible amount (<5 ppm) and 56 % of households consumed an insufficient amount (5–15 ppm) of iodine from salt.
Conclusions
Although there was an overall improvement in iodine nutrition as revealed by decreased goitre prevalence and increased median urinary iodine levels, there were several pockets of severe deficiency that require a more targeted approach. Poor coverage, the use of unpackaged crystal salt with inadequate iodine and the washing of salt before use by 90 % of rural households are the major causes of persisting iodine-deficiency disorders. This demonstrates lapses in USI implementation, lack of monitoring and the need to identify hot spots. We advocate strengthening the USI programme with a mass education component, the supply of adequately iodized salt and the implementation of complementary strategies for vulnerable groups, particularly neonates and lactating mothers.
We analysed the responses of Anabaena doliolum to elevated levels of copper and zinc in batch and semi-continuous cultures. Approximately 10, 4 and 8 and 5-times greater inhibition in final yield of A. doliolum occurred at 1, 2 μM Cu and 2.5 and 5 μM of Zn, respectively, in semi-continuous culture in comparison to batch culture. Protein, chlorophyl a and carotenoid contents of A. doliolum showed significantly (P < 0.05) higher inhibition by test metals in semi-continuous culture than in batch culture. The greater sensitivity of different parameters of the test organism was related to the high metal content of the cells grown in semi-continuous system. Moreover, enhancement of pH of the culture suspension in batch culture showed a negative relationship with metal accumulation, and therefore with toxicity. This was due to decrease in free ionic concentrations of test metals. Carotenoids acted as a metal detoxifying agent by minimizing metal-induced inhibition in batch culture as was evident from its negative relationship with metal toxicity.
In this paper the focusing/defocusing of (i) a single Gaussian electromagnetic beam and (ii) a number of coaxial Gaussian electromagnetic beams, propagating in the extraordinary mode along the Earth's magnetic field in the ionosphere has been investigated in the paraxial approximation. The growth of a sinusoidal instability on account of self-focusing has also been studied. The nonlinearity in the dielectric function, responsible for the focusing/defocusing arises from the redistribution of the electron density, caused by the non-uniform distribution of the electron temperature. The electron temperature is determined by the energy balance for electrons/ions taking into account the Ohmic heating, the collisions and the radiation from the sun. The wave frequency has been assumed to be greater than the plasma frequency. The electron cyclotron frequency due to the Earth's magnetic field in the ionosphere is much larger than the electron collision frequency. This is specifically true for a height of 150 km. Numerical results have been presented for a range of parameters and a discussion of the same has been presented.
For coaxial Gaussian electromagnetic beams of equal width, a relation between the weighted sum of axial irradiances and the width of the beams, which corresponds to the propagation in a plasma, without convergence or divergence has been obtained in the paraxial approximation. The collisional (with and without thermal conduction), ponderomotive and relativistic nonlinearities have been separately considered in this investigation. The investigation has relevance to the study and application of multi-wave interaction phenomena such as the growth of combination frequencies, plasma beat wave acceleration and enhanced penetration in an overdense plasma.
In this communication the interaction between two Gaussian electromagnetic beams in an ionic collision dominated plasma has been investigated, when the axes of the two beams are initially (z = 0) parallel along the z-axis in the xz plane; the beams are initially propagating in the z-direction. Taking into account the loss of electron energy by collisions and by thermal conduction, the energy balance equation for electrons has been solved to obtain the space dependence of the electron temperature and the dielectric function has been expressed as a function of the electron temperature; this expression for the dielectric function has been substituted in the wave equation and a solution of the resulting nonlinear equation obtained in the paraxial approximation. Second-order coupled ordinary differential equations have been obtained for the distance between the centers of the beams and the beam widths in the x- and y-directions as a function of the distance of propagation along the z-axis. The equations have been solved numerically for a range of parameters and a discussion of the results is presented for the case when the two beams have the same axial irradiance, frequency and width. From simple considerations it is seen that the beams attract each other when 2xo < wro and in this situation beams are close enough for the paraxial approximation to be valid.
Myringoplasty is an established procedure. However, the quest is on to improve the results further by studying the different influencing factors, that could possibly affect the outcome. In the present randomized prospective study of one year’s duration, 60 patients having dry, large and subtotal perforations of the tympanic membrane were subjected to myringoplasty, 30 by the overlay technique and 30 by the underlay technique keeping all other influencing factors constant. The graft take-up rate was found to be the same (93.3 per cent) in both techniques but the underlay technique was judged to be better because of its technical ease, better assessment of ossicular chain integrity and mobility, less time consumption (55 minutes vs 90 minutes), earlier healing of graft (four to six weeks vs six to eight weeks), hearing gain in more patients (92.8 per cent vs 57.1 per cent) and fewer minor complications (6.6 per cent vs 33.3 per cent).
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