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Centrifuge casting is a new technique wherein a mold assembly is made to rotate at a certain speed that will induce higher 'G' force to the molten metal. The existing higher rotational force creates a compositional gradient that segregate phases with different densities. In this work, an attempt has been made to develop Al alloy/SiCP FGMs. It has been observed that due to the higher density of SiC compared to Aluminum, the bottom part of the casting is rich in SiC particles with good resistance to wear, and the top of the casting results in high toughness as it is more of Al alloy. In the present work FG Composites are produced using hypereutectic (17%Si) Al-Si alloy using centrifuge casting technique with SiC particulate(SiCP) as reinforcement using stir casting followed by centrifuge casting. The samples were characterized for microstructure, hardness, and wear. It was found that there is a gradation in the sample for all the above said properties from top to bottom of the sample. It was found that Al-17wt% Si matrix alloy reinforced with 2% SiCP yielded a maximum hardness of about 66BHN at 400rpm while for 4% and 6% the hardness was found to be 82 and 94BHN. The results revealed that the wear resistance was high at both the ends of the specimen due to segregation of Si at one end and SiCp at the other end. [ABSTRACT FROM AUTHOR]

RNA helicases function as molecular motors that rearrange RNA secondary structure, potentially performing roles in any cellular process involving RNA metabolism in an ATP-dependent manner and play an important role in protein synthesis. Pennisetum glaucum 47 (PG47) RNA helicase overexpressed in groundnut (Arachis hypogaea L.) cultivar GPBD-4 improved drought tolerance. The transgenics plants were confirmed for presence, expression and stable integration by Kanamycin screening, genomic DNA PCR, RT-PCR and Southern analyses respectively. In T3 generation, the promising transgenic events were identified based on stress tolerance and improvement in productivity. The transgenic events showed enhanced stay-green phenotype and increased chlorophyll stability under drought stress. The transgenics also showed reduced chlorophyll retardation under NaCl, PEG and etherel-induced stress conditions. Transgenic plants showed increased yield than wild type under stress conditions. Results suggested that PG47 RNA helicase contributing for enhanced droughtadaptive traits and improved productivity under water-limited conditions. [ABSTRACT FROM AUTHOR]

Pongamia pinnata (L) Pierre, belonging to subfamily Papilionoideae is a medium sized tree native to humid and subtropical environments. Seeds of Pongamia have about 30-35 percent oil and up to 27-28 percent oil can be expressed in crusher. The present research analyzes the variations with respect to seed dimensions of P. pinnata in the study area. Seed length, width and thickness showed significant variation within the zone and between the zones. Arithmetic Mean diameter, Geometric Mean Diameter, Square Mean Diameter and Equivalent Mean diameter also showed significant variations between three accessions from two different zones. But Aspect ratio has not shown any significant variation between the zones. Unlike Aspect ratio significant variations between the zones were observed for Sphericity, Surface area and Seed Volume. Significant variations within the zone for above parameters suggest existence of microclimate. Seed source variability for P. pinnata was largely attributed to the heterogeneity of the genotypes and the genotype X environment interactions. [ABSTRACT FROM AUTHOR]

Anisotropy of magnetic susceptibility (AMS) fabrics have been studied for the first time on a well constrained Paleoproterozoic Bangalore-Karimnagar giant mafic dyke swarm at ca. 2367 Ma in the Dharwar craton, south India. A total number of 43 samples from nine sites representing five N-E trending dykes have been subjected to AMS and conventional rock magnetic studies. The magnetic fabric is principally ferromagnetic in origin as the magnetic susceptibility values are >10−3 SI, which is further supported by Isothermal Remanent magnetization (IRM) studies. Hysteresis loops, Isothermal remanent magnetisation (IRM), thermomagnetic properties and optical observations indicate that pseudo single domain (PSD) low-titanium magnetite particles dominate the low field susceptibility of samples. The magnetic fabrics results correspond well with the comprehensive field studies. However, the degree of anisotropy results ranges from 0.4% to 12.8%, with a mean total anisotropy of 4.7%. The principal AMS axes for samples from all the sites are tightly clustered on equal area plots, and two main fabrics were revealed in the Bangalore-Karimnagar giant dyke swarm. In the first, the maximum susceptibility axes is sub-horizontal and parallel to the dyke walls, minimum susceptibility axes plot near the pole of the dyke. It is interpreted as the primary magma flow direction. A second fabric with maximum susceptibility axis is sub-horizontal and perpendicular to the dyke walls, and is interpreted as a result of vertical compaction at a late stage of crystallization. Preliminary results suggest that dyke propagation in the Bangalore-Karimnagar giant dyke swarm preserve a flow-induced fabric slightly upwards to the NE and magma flow is sub-horizontal. • We report Anisotropy of Magnetic Susceptibility results on a large Paleoproterozoic dyke swarm (2367 Ma) from Dharwar craton. • AMS results show predominant lateral magma flow at the time of dyke emplacement. • AMS results show predominant sub-horizontal flow is due to the plume situated at very distant place. [ABSTRACT FROM AUTHOR]