169 research outputs found
Floral biology and pollinator captivating semiochemicals in Goniothalamus wynaadensis (Bedd.) Bedd. (Annonaceae) an endemic tree species of the Western Ghats
Goniothalamus wynaadensis (Bedd.) Bedd. (Family Annonaceae) is an endemic tree species growing in the evergreen forests of the Western Ghats up to 900m asl. The present study aims at understanding the functional floral traits and semiochemicals found in G. wynaadensis which support plant-pollinator interactions. The study revealed G. wynaadensis exhibits abbreviated anthesis (c.28hrs). Goniothalamus flowers exhibit unique features of cantharophily. The study indicated that outcrossing is promoted by protogyny, and pollination efficiency is enhanced by pollen aggregation, anthesis duration, and pollinator trapping which involves a close alignment between petal movements and the circadian rhythm of pollinators. Curculionidae and Nitidulidae beetles are effective pollinators of the plant. In beetle-pollinated flowers, floral scent is a crucial component for pollinator attraction. G. wynaadensis has a strong fruity aroma. The floral scent analysis performed using headspace solid- phase microextraction combined with GC-MS detected various semiochemicals that support plant-pollinator interactions. Ethyl butyrate, isobutyl acetate, 3 hydroxy 3 methyl 2 butanol, isopentyl acetate, and 3 methyl 1 butanol dominate the floral scent of G. wynaadensis
Institution village linkage programme Coastal Agro Ecosystem & Interventions
Agriculture, animal husbandry and fisheries provide maximum employment in the primary sector
and form the major source of income and livelihood security of about 70 percent of the population in
India. After the introduction of the liberalisation policy and giving thrust for the adoption of improved
technologies, there has been a spectacular increase in production in all these segments and the country
has witnessed a rapid structural change. Massive adoption of scientific inventions and technological
interventions witnessed revolutionary changes in all sectors of development and quality of life of
people. Achieving self-sufficiency on food front has been one of the finest Indian successes of the
post independence era. The food grain production increased four times (from 50.8 million tonnes
during 1950-51 to 198.7 million tonnes during 2000-01) since independence as compared to the
three-fold increase in population. Further significant advances have also been made in the production
of milk, fish, oilseeds, fruits and vegetables. In fisheries, the country has ushered in the blue revolution
with gross production reaching 5.6 million metric tonnes offish and edible invertebrates during 2000-
2001. India is the second largest Asian country in terms of culture fisheries and the third largest in
terms of capture fisheries (NAAS, 2001). Due to concerted efforts on strategic research and production
technology in oilseeds sector, the country witnessed yellow revolution with the production reaching
25 million tonnes per annum. This was possible as a result of strong agricultural research support
provided by the National Agricultural Research System (NARS)
CarD stabilizes mycobacterial open complexes via a two-tiered kinetic mechanism
CarD is an essential and global transcriptional regulator in mycobacteria. While its biological role is unclear, CarD functions by interacting directly with RNA polymerase (RNAP) holoenzyme promoter complexes. Here, using a fluorescent reporter of open complex, we quantitate RP(o) formation in real time and show that Mycobacterium tuberculosis CarD has a dramatic effect on the energetics of RNAP bound complexes on the M. tuberculosis rrnAP3 ribosomal RNA promoter. The data reveal that Mycobacterium bovis RNAP exhibits an unstable RP(o) that is stabilized by CarD and suggest that CarD uses a two-tiered, concentration-dependent mechanism by associating with open and closed complexes with different affinities. Specifically, the kinetics of open-complex formation can be explained by a model where, at saturating concentrations of CarD, the rate of bubble collapse is slowed and the rate of opening is accelerated. The kinetics and open-complex stabilities of CarD mutants further clarify the roles played by the key residues W85, K90 and R25 previously shown to affect CarD-dependent gene regulation in vivo. In contrast to M. bovis RNAP, Escherichia coli RNAP efficiently forms RP(o) on rrnAP3, suggesting an important difference between the polymerases themselves and highlighting how transcriptional machinery can vary across bacterial genera
Reaching the unreached: Highlights of Institution Village Linkage Programme of CMFRI
Reaching the unreached: Highlights of Institution Village Linkage Programme of CMFR
Effects of increasing the affinity of CarD for RNA polymerase on Mycobacterium tuberculosis growth, rRNA transcription, and virulence
CarD is an essential RNA polymerase (RNAP) interacting protein in Mycobacterium tuberculosis that stimulates formation of RNAP-promoter open complexes. CarD plays a complex role in M. tuberculosis growth and virulence that is not fully understood. Therefore, to gain further insight into the role of CarD in M. tuberculosis growth and virulence, we determined the effect of increasing the affinity of CarD for RNAP. Using site-directed mutagenesis guided by crystal structures of CarD bound to RNAP, we identified amino acid substitutions that increase the affinity of CarD for RNAP. Using these substitutions, we show that increasing the affinity of CarD for RNAP increases the stability of the CarD protein in M. tuberculosis. In addition, we show that increasing the affinity of CarD for RNAP increases the growth rate in M. tuberculosis without affecting 16S rRNA levels. We further show that increasing the affinity of CarD for RNAP reduces M. tuberculosis virulence in a mouse model of infection despite the improved growth rate in vitro. Our findings suggest that the CarD-RNAP interaction protects CarD from proteolytic degradation in M. tuberculosis, establish that growth rate and rRNA levels can be uncoupled in M. tuberculosis and demonstrate that the strength of the CarD-RNAP interaction has been finely tuned to optimize virulence. IMPORTANCE Mycobacterium tuberculosis, the causative agent of tuberculosis, remains a major global health problem. In order to develop new strategies to battle this pathogen, we must gain a better understanding of the molecular processes involved in its survival and pathogenesis. We have previously identified CarD as an essential transcriptional regulator in mycobacteria. In this study, we detail the effects of increasing the affinity of CarD for RNAP on transcriptional regulation, CarD protein stability, and virulence. These studies expand our understanding of the global transcription regulator CarD, provide insight into how CarD activity is regulated, and broaden our understanding of prokaryotic transcription
Economic loss and gains of marine fishing along Kerala coast
Along the Kerala coast, the capital investment in mechanized, motorised and non-mechanised sectors of various
craft-gear combinations, on an average, ranges from Rs. 23000 for a small catamaran unit in the non-motorised
sector to RS.25 lakh for a small trawler in the mechanised sector. The average operating cost of individual craft
among these categories varies between Rs.8,000 and Rs.13 lakh providing returns to the tune of 15 per cent to 140
per cent of the capital investment. Economic loss due to juvenile fishing is severe for species like flatfish with a
difIerential ratio 0.14, anchovies with 0.20, thread tin breams with 0.21 , carangids 0.29 and shrimps 0.33
Investigation of Plasma Treatment on Micro-Injection Moulded Microneedle for Drug Delivery
YesPlasma technology has been widely used to increase the surface energy of the polymer surfaces for many industrial applications; in particular to increase in wettability. The present work was carried out to investigate how surface modification using plasma treatment modifies the surface energy of micro-injection moulded microneedles and its influence on drug delivery. Microneedles of polyether ether ketone and polycarbonate and have been manufactured using micro-injection moulding and samples from each production batch have been subsequently subjected to a range of plasma treatment. These samples were coated with bovine serum albumin to study the protein adsorption on these treated polymer surfaces. Sample surfaces structures, before and after treatment, were studied using atomic force microscope and surface energies have been obtained using contact angle measurement and calculated using the Owens-Wendt theory. Adsorption performance of bovine serum albumin and release kinetics for each sample set was assessed using a Franz diffusion cell. Results indicate that plasma treatment significantly increases the surface energy and roughness of the microneedles resulting in better adsorption and release of BSA
Impact of Capital Structure on Profitability: Evidence from Star Category Hotels in Sri Lanka
This study examines the impact of the capital structure on the profitability of the 25 registered hotels in the Sri Lanka Tourism Development Authority (SLTDA). The data on capital structure and profitability collected from audited annual reports (2011 to 2021), were analyzed using panel regression methodology and presented through descriptive statistics and models. Total debt to total assets, total debt to total equity and interest coverage ratio were used to measure the capital structure and return on assets and return on equity were used to measure the profitability of the firm. The study found no significant impact of debt to equity ratio and interest coverage ratio on the return on equity and return on asset. There is a significant impact of debt to asset and return on equity and the return on asset. These results concluded that there is an impact of capital structure on the profitability of the hotel industry in Sri Lanka.
© 2022 The Authors. Published by Department of Estate Management and Valuation, University of Sri Jayewardenepura
Key Words: Capital structure; Profitability; Registered Star Category Hotels in Sri Lank
High-performance photorefractive polymer operating at 1550 nm with near-video-rate response time
© 2005 American Institute of Physics. The electronic version of this article is the complete one and can be found at: http://dx.doi.org/10.1063/1.2117610DOI: 10.1063/1.2117610The development of a high-performance photorefractive polymer composite operating at 1550 nm is reported. We show 40% internal diffraction efficiency with response time of 35 ms and a net gain of 20 cm ⁻¹ in four-wave mixing and two-beam coupling experiments, respectively. This is more than an order of magnitude improvement in the diffraction efficiency and net two beam coupling gain and two orders of magnitude in the response time than the previously reported photorefractive polymer operating at this technologically important wavelength. The improvement in photorefractive characteristics is accomplished by an enhanced orientation of the nonlinear optical chromophore in the present composit
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