Mapping of Thar Desert Grasslands Using High Resolution Carto-Data (A Case Study of Jodhpur District)

The spatio-temporal condition and trend of grasslands in India at village-level is still not known completely. Historical and contemporary monitoring and assessment protocols are primarily based on the wisdom, knowledge and experience of village-level revenue officer (patwari) which is just significant from the statistical point of view. Contrastingly, such grassland areas are considered to be of high priority by government authorities for the long-term conservation of biodiversity. Protection, development and sustainable use of grasslands are very important for the rural economy and livestock. The major grasslands now survive west of isohyets 200 to 250 mm rainfall where livestock population is more than human beings. Animal husbandry plays such an important role in the lifestyle and economics of the inhabitants, scientific management of the grasslands, on which the animals depend for nourishment, is totally neglected. Pastoralism has coexisted within dry lands for decades. The constant pressure from an increasing human population and anthropogenic activities, particularly mining, has caused considerable damage to this unique desert grassland ecosystem. Several important grasslands have been converted to agricultural fields and the pressure to convert more grassland into such uses is mounting. Area under grasslands in the Jodhpur district has declined very sharply. It was 6.4% in 1976 (Sen, 1978) but has been reduced to \u3c 1.5% of the district area. Grasslands are one of the important classes of land use mapping exercise. The aim of the present project was to identify and map all grasslands and grazing areas in the Jodhpur district using spectral signatures of 2012-13 high resolution satellite data of Cartosat LISS-IV plus PAN merged and compare with 1976-77 and 2005-06 data. There is a need to sustain and conserve grasslands at grassroots level because these are the important life-supporting mechanism of the dry region. There is an immediate scope for the spatial and temporal scale dependence of assessment tools for grassland monitoring and undertaking research at village-to district-scales to incorporate geographic information systems and satellite remote sensing data, as well as new ecological concepts from landscape ecology and complex systems science

Ultrasonic pulse induced mechanoluminescence of europium doped strontium aluminate micro-crystals

When rare earth doped strontium aluminate micro-crystals are exposed to ultrasonic pulse, then mechanumnescence (ML) is induced. The intensity of ML is proportional to the power of ultrasonic pulse used for ML excitation. The ML in europium doped strontium aluminate micro-crystals can be understood on the basis of the piezoelectrically induced electron detrapping model. On the basis of the piezoelectrically-induced electron detrapping model, expressions are derived for the general kinetics of ML intensity, rise of ML intensity, peak ML intensity and decay of ML intensity, in which good agreement is found between the theoretical and experimental results. A linear relation between the ML intensity and the ultrasonic power can also be understood on the basis of the proposed theory. The present investigation shows that the ML can be used to detecting the presence of ultrasonic waves and also for the measurement of ultrasonic power.&nbsp

Dual-band fiber optic parametric amplifier for bi-directional transient-sensitive fiber optical transmission links

We demonstrate an in-line polarization-insensitive fiber optic parametric amplifier (PI-FOPA) to simultaneously amplify burst and non-burst signals transmitted in opposite directions in C and L bands. The PI-FOPA provides >16 dB polarization insensitive net gain for signals which are 53 nm apart and counter-propagating in an extended reach link: an upstream bursty signal at 1533 nm and a downstream non-burst signal at 1586 nm. The PI-FOPA potential application as an in-line dual-band amplifier in transient-sensitive communication links is demonstrated by its employment in an extended reach access network with a symmetric 10 Gbps capacity

Experimental comparison of fiber optic parametric, Raman and erbium amplifiers for burst traffic for extended reach PONs

We experimentally compare the performance of a polarization-independent fiber optic parametric amplifier (FOPA), a discrete Raman amplifier and a commercial erbium doped fiber amplifier (EDFA) for burst traffic amplification in extended reach passive optical networks (PON). We demonstrate that EDFA and Raman amplifiers suffer from severe transient effects, causing penalty on receiver sensitivity >5 dB for traffic bursts of 10 Gbps on-off keying signal shorter than 10 µs. On the other hand, we demonstrate that FOPA does not introduce a penalty on receiver sensitivity when amplifying signal bursts as short as 5 µs as compared to a non-burst signal. Therefore, FOPA used as a drop-in replacement for an EDFA or Raman amplifier allows us to improve receiver sensitivity by >3 dB for short signal bursts. We conclude that FOPA allows substantially increased power budget for an extended reach PON transmitting variable duration bursts. In addition, we identify the maximum burst duration tolerated by each examined amplifier

Fibre optic parametric amplifier for high capacity burst-mode access networks

We compare performance of a polarization insensitive fiber optic parametric amplifier (PI-FOPA), a commercial erbium doped fiber amplifier (EDFA) and a discrete Raman amplifier (DRA) in a 50 km long-reach optical access network transmitting bursts of 10 Gbps signal with traffic density ranged from 5% to 97%. We demonstrate that for the same power budget the PI-FOPA allows for transmission of bursty traffic with density up to 97% while DRA and EDFA are limited to 30% and 15%, respectively. Alternatively, we demonstrate PI-FOPA to allow for 3 dB and 5 dB higher power budget than the DRA and EDFA, respectively, for the worst case scenario of 75% traffic density

Parametric Amplification and Wavelength Conversion in Dual-Core Highly Nonlinear Fibers

In this paper we experimentally show parametric amplification and wavelength conversion in a custom manufactured dual-core highly nonlinear fiber. On-off gain > 10 dB and conversion efficiencies between −1 and −8.5 dB were measured for both cores. The estimated effective nonlinear parameter for the cores of the fiber are 6.6 W−1.km−1 and 6.3 W−1.km−1, while the zero-dispersion wavelength for the individual cores is shown to be relatively close from each other. Furthermore, complementary analytical and numerical results show that coupled cores fiber optical parametric amplifier offer the potential of wide-band gain even when they have significantly distinct zero-dispersion wavelengths

Mining the chickpea composite collection for allelic variation

Chickpea, Cicer arietinum L., is believed to have originated in south-east Turkey. However, at present, the major chickpea-growing countries are India, Pakistan, Iran, Turkey, Australia, Ethiopia, and Mexico. Chickpea is a leguminous food crop, self-pollinating, and diploid. Its gene pool consists of 43 species: one annual cultivated (i.e. chickpea), eight annual wild, and 34 perennial wild species. Two types of chickpea are known: desi types with coloured flowers, and angular-shaped and dark-coloured seeds, primarily grown in South Asia and Africa; and kabuli types with white flowers, owl’s head-shaped and beige-coloured seeds, and grown mostly in Mediterranean countries. To study the allelic richness and diversity associated with beneficial traits, a composite set of 3000 chickpea germplasm accessions was constituted. This set included the chickpea core collection, old and new cultivars and traitspecific germplasm accessions from ICRISAT and accessions representing the ICARDA collection

Multiwavelength Intraday Variability of the BL Lac S5 0716+714

We report results from a 1 week multi-wavelength campaign to monitor the BL Lac object S5 0716+714 (on December 9-16, 2009). In the radio bands the source shows rapid (~ (0.5-1.5) day) intra-day variability with peak amplitudes of up to ~ 10 %. The variability at 2.8 cm leads by about 1 day the variability at 6 cm and 11 cm. This time lag and more rapid variations suggests an intrinsic contribution to the source's intraday variability at 2.8 cm, while at 6 cm and 11 cm interstellar scintillation (ISS) seems to predominate. Large and quasi-sinusoidal variations of ~ 0.8 mag were detected in the V, R and I-bands. The X-ray data (0.2-10 keV) do not reveal significant variability on a 4 day time scale, favoring reprocessed inverse-Compton over synchrotron radiation in this band. The characteristic variability time scales in radio and optical bands are similar. A quasi-periodic variation (QPO) of 0.9 - 1.1 days in the optical data may be present, but if so it is marginal and limited to 2.2 cycles. Cross-correlations between radio and optical are discussed. The lack of a strong radio-optical correlation indicates different physical causes of variability (ISS at long radio wavelengths, source intrinsic origin in the optical), and is consistent with a high jet opacity and a compact synchrotron component peaking at ~= 100 GHz in an ongoing very prominent flux density outburst. For the campaign period, we construct a quasi-simultaneous spectral energy distribution (SED), including gamma-ray data from the FERMI satellite. We obtain lower limits for the relativistic Doppler-boosting of delta >= 12-26, which for a BL\,Lac type object, is remarkably high.Comment: 16 pages, 15 figures, table 2; Accepted for Publication in MNRA

Genomics-assisted breeding in four major pulse crops of developing countries: present status and prospects

The global population is continuously increasing and is expected to reach nine billion by 2050. This huge population pressure will lead to severe shortage of food, natural resources and arable land. Such an alarming situation is most likely to arise in developing countries due to increase in the proportion of people suffering from protein and micronutrient malnutrition. Pulses being a primary and affordable source of proteins and minerals play a key role in alleviating the protein calorie malnutrition, micronutrient deficiencies and other undernourishment-related issues. Additionally, pulses are a vital source of livelihood generation for millions of resource-poor farmers practising agriculture in the semi-arid and sub-tropical regions. Limited success achieved through conventional breeding so far in most of the pulse crops will not be enough to feed the ever increasing population. In this context, genomics-assisted breeding (GAB) holds promise in enhancing the genetic gains. Though pulses have long been considered as orphan crops, recent advances in the area of pulse genomics are noteworthy, e.g. discovery of genome-wide genetic markers, high-throughput genotyping and sequencing platforms, high-density genetic linkage/QTL maps and, more importantly, the availability of whole-genome sequence. With genome sequence in hand, there is a great scope to apply genome-wide methods for trait mapping using association studies and to choose desirable genotypes via genomic selection. It is anticipated that GAB will speed up the progress of genetic improvement of pulses, leading to the rapid development of cultivars with higher yield, enhanced stress tolerance and wider adaptability