Abstract: | Concentrations and distributions of trace metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in surficial sediments of the Cochin backwaters were studied during both monsoon and pre-monsoon periods. Spatial variations were in accordance with textural charaterstics and organic matter content. A principal component analysis distinguished three zones with different metal accumulation capacity: (i) highest levels in north estuary, (ii) moderate levels in central zone, and (iii) lowest levels in southern part. Trace metal enrichments are mainly due to anthropogenic contribution of industrial, domestic, and agricultural effluents, whose effect is enhanced by settling of metals due to organic flocculation and inorganic precipitation associated with salinity changes. Enrichments factors using Fe as a normalizer showed that metal contamination was the product of anthropogenic activities. An assessment of degree of pollution-categorized sediments as moderately polluted with Cu and Pb, moderately-to-heavily polluted with Zn, and heavily-to-extremely polluted with Cd. Concentrations at many sites largely exceed NOAA ERL (e.g., Cu, Cr, and Pb) or ERM (e.g., Cd, Ni, and Zn). This means that adverse effects for benthic organisms are possible or even highly probable. |
Description: | The ScientificWorld Journal Volume 2012, Article ID 972839, 17 pages |
URI: | http://dyuthi.cusat.ac.in/purl/4603 |
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ToxicMetals Enr ... thwest Coast of India).pdf | (7.707Mb) |
Abstract: | In this note,the (t) properties of five class are studied. We proved that the classes of cographs and clique perfect graphs without isolated vertices satisfy the (2) property and the (3) property, but do not satisfy the (t) property for tis greater than equal to 4. The (t) properties of the planar graphs and the perfect graphss are also studied . we obtain a necessary and suffieient conditions for the trestled graph of index K to satisfy the (2) property |
URI: | http://dyuthi.cusat.ac.in/purl/1533 |
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The (t) property of some classes of graphs.PDF | (3.911Mb) |
Abstract: | The transient characteristics of an erbium-doped fiber (F.DF) laser, which can switch between wavelengths. are investigated. 77te laser has a set of coupled linear cavities. The slow gain dynamics of EDFs and the cross-gain saturation in the coupled cavities give rise to delayed switching responses and relocation oscillations, which are respertively measured to be l ins and 3.5 ms for the worst rase, and which mar be decreased by increasing the pump power. Thus, the switching speed of the laser may be higher than 100 Hz |
URI: | http://dyuthi.cusat.ac.in/purl/1390 |
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Transient respo ... inear coupled cavities.PDF | (540.5Kb) |
Abstract: | Transparent diode heterojunction on ITO coated glass substrates was fabricated using p-type AgCoO2 and n-type ZnO films by pulsed laser deposition (PLD). The PLD of AgCoO2 thin films was carried out using the pelletized sintered target of AgCoO2 powder, which was synthesized in-house by the hydrothermal process. The band gap of these thin films was found to be ~3.89 eV and they had transmission of~55% in the visible spectral region. Although Hall measurements could only indicate mixed carrier type conduction but thermoelectric power measurements of Seebeck coefficient confirmed the p-type conductivity of the grown AgCoO2 films. The PLD grown ZnO films showed a band gap of ~3.28 eV, an average optical transmission of ~85% and n-type carrier density of~4.6×1019 cm− 3. The junction between p-AgCoO2 and n-ZnO was found to be rectifying. The ratio of forward current to the reverse current was about 7 at 1.5 V. The diode ideality factor was much greater than 2. |
URI: | http://dyuthi.cusat.ac.in/purl/791 |
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Synthesis of Zn ... by hydrothermal method.pdf | (1.906Mb) |
Abstract: | Tribasic lead sulphate is tried as a practical curing agent for polychloroprene. The cure characteristics of the compounds as well as the technical properties of the vulcanizates show that it can act as a potential curative. |
URI: | http://dyuthi.cusat.ac.in/purl/840 |
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Rani Joseph and others,Tribasic lead..1986.PDF | (3.857Mb) |
Abstract: | This paper presents a cascaded 2-2-2 reconfigurable sigma-delta modulator that can handle GSM, WCDMA and WLAN standards. The modulator makes use of a low-distortion swing suppression topology which is highly suitable for wide band applications. In GSM mode, only the first stage (2nd order Σ-Δ ADC) is turned on to achieve 88dB dynamic range with oversampling ratio of 160 for a bandwidth of 200KHz; in WCDMA mode a 2-2 cascaded structure (4th order) is turned on with 1-bit in the first stage and 2-bit in the second stage to achieve 74 dB dynamic range with oversampling ratio of 16 for a bandwidth of 2MHz and a 2-2-2 cascaded MASH architecture with a 4-bit in the last stage to achieve a dynamic range of 58dB for a bandwidth of 20MHz. The novelty lies in the fact that unused blocks of second and third stages can be switched off taking into considerations like power consumption. The modulator is designed in TSMC 0.18um CMOS technology and operates at 1.8 supply voltage. |
Description: | SOC Conference, 2007 IEEE International,309-312 |
URI: | http://dyuthi.cusat.ac.in/purl/4523 |
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A Triple-Mode F ... dma Wlan Applications.pdf | (557.8Kb) |
Abstract: | This work presents a triple-mode sigma-delta modulator for three wireless standards namely GSM/WCDMA and Bluetooth. A reconfigurable ADC has been used to meet the wide bandwidth and high dynamic range requirements of the multi-standard receivers with less power consumption. A highly linear sigma-delta ADC which has reduced sensitivity to circuit imperfections has been chosen in our design. This is particularly suitable for wide band applications where the oversampling ratio is low. Simulation results indicate that the modulator achieves a peak SNDR of 84/68/68 dB over a bandwidth of 0.2/3.84/1.5 MHz with an oversampling ratio 128/8/8 in GSM/WCDMA/Bluetooth modes respectively |
Description: | 10th International Conference on Information Technology |
URI: | http://dyuthi.cusat.ac.in/purl/4514 |
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A Triple-mode S ... for Wireless Standards.pdf | (540.2Kb) |
Abstract: | This paper deals with brief overview of the developments of international provisions on IPR related to public health. It discusses flexibilities before and after TRIPS Agreement and difficulties faced by developing countries in implementing TRIPS obligations and protecting public health. Also discussed are the reasons for the Doha Declaration and issues relating to implementation of Para 6 of the Declaration. Discusses the inadequacy in the compulsory licence based approach to solve public health crisis and argues for a more comprehensive approach to find a long term solution to the public health issues |
Description: | Journal of Intellectual Property Rights Vol 13, September 2008, pp 395-400 |
URI: | http://dyuthi.cusat.ac.in/purl/4717 |
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TRIPS Agreement ... f International Issues.pdf | (72.83Kb) |
Abstract: | Several oral vaccination studies have been undertaken to evoke a better protection against white spot syndrome virus (WSSV), amajor shrimp pathogen. Formalin-inactivated virus andWSSV envelope protein VP28 were suggested as candidate vaccine components, but their uptake mechanism upon oral delivery was not elucidated. In this study the fate of these components and of live WSSV, orally intubated to black tiger shrimp (Penaeus monodon) was investigated by immunohistochemistry, employing antibodies specific for VP28 and haemocytes. The midgut has been identified as the most prominent site of WSSV uptake and processing. The truncated recombinant VP28 (rec-VP28), formalin-inactivated virus (IVP) and live WSSV follow an identical uptake route suggested as receptor-mediated endocytosis that starts with adherence of luminal antigens at the apical layers of gut epithelium. Processing of internalized antigens is performed in endo-lysosomal compartments leading to formation of supra-nuclear vacuoles. However, the majority of WSSV-antigens escape these compartments and are transported to the inter-cellular space via transcytosis. Accumulation of the transcytosed antigens in the connective tissue initiates aggregation and degranulation of haemocytes. Finally the antigens exiting the midgut seem to reach the haemolymph. The nearly identical uptake pattern of the different WSSV-antigens suggests that receptors on the apical membrane of shrimp enterocytes recognize rec-VP28 efficiently. Hence the truncated VP28 can be considered suitable for oral vaccination, when the digestion in the foregut can be bypassed |
Description: | Fish & Shellfish Immunology 34 (2013) 159-166 |
URI: | http://dyuthi.cusat.ac.in/purl/4064 |
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Truncated VP28 ... gut of Penaeus monodon.pdf | (1.526Mb) |
Abstract: | Protease inhibitors can be versatile tools mainly in the fields of medicine, agriculture and food preservative applications. Fungi have been recognized as sources of protease inhibitors, although there are only few such reports on mushrooms. This work reports the purification and characterization of a trypsin inhibitor from the fruiting body of edible mushroom Pleurotus floridanus (PfTI) and its effect on the activity of microbial proteases. The protease inhibitor was purified up to 35-fold by DEAE-Sepharose ion exchange column, trypsin-Sepharose column and Sephadex G100 column. The isoelectric point of the inhibitor was 4.4, and its molecular mass was calculated as 37 kDa by SDS-PAGE and 38.3 kDa by MALDI-TOF. Inhibitory activity confirmation was by dot-blot analysis and zymographic activity staining. The specificity of the inhibitor toward trypsin was with Ki of 1.043×10−10 M. The inhibitor was thermostable up to 90 °C with maximal stability at 30 °C, active over a pH range of 4–10 against proteases from Aspergillus oryzae, Bacillus licheniformis, Bacillus sp. and Bacillus amyloliquefaciens. Results indicate the possibility of utilization of protease inhibitor from P. floridanus against serine proteases |
Description: | Appl Biochem Biotechnol (2014) 173:167–178 DOI 10.1007/s12010-014-0826-1 |
URI: | http://dyuthi.cusat.ac.in/purl/4268 |
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Trypsin Inhibit ... es of Microbial Origin.pdf | (597.3Kb) |
Abstract: | rectangular low-density, high-permittivity dielectric resona or antenna (DRA) excited by T-shaped microstrip feed offering a 2:1 VSWR bandwidth of -22% at 2.975 GHz is reported. The design methoaology and experimental results of the antenna are discussed. The excellent gain and radiation performance of the proposed antenna project: it as a potential candidate for telecommunication applications |
URI: | http://dyuthi.cusat.ac.in/purl/1416 |
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T-strip-fed hig ... broadband applications.PDF | (928.9Kb) |
Abstract: | The present work describes the immobilization of α-amylase over well ordered mesoporous molecular sieve SBA-15 with different pore diameters synthesized by post synthesis treatment (PST) hydrothermally after reaction at 40°C. The materials were characterized by N 2 adsorption–desorption studies, small angle X-ray diffraction, scanning electron microscopy and high resolution transmission electron microscopy. Since α-amylase obtained from Bacillus subtilis has dimensions of 35 × 40 × 70 Å it is expected that the protein have access to the pore of SBA-15 (PST-120°C) with diameter 74 Å. The pore dimension is appropriate to prevent considerable leaching. The rate of adsorption of the enzyme on silica of various pore sizes revealed the influence of morphology, pore diameter, pore volume and pH. |
URI: | http://dyuthi.cusat.ac.in/purl/2265 |
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Dyuthi-SS58.pdf | (465.4Kb) |
Abstract: | The mathematical formulation of empirically developed formulas Jirr the calculation of the resonant frequency of a thick-substrate (h s 0.08151 A,,) microstrip antenna has been analyzed. With the use qt' tunnel-based artificial neural networks (ANNs), the resonant frequency of antennas with h satisfying the thick-substrate condition are calculated and compared with the existing experimental results and also with the simulation results obtained with the use of an IE3D software package. The artificial neural network results are in very good agreement with the experimental results |
URI: | http://dyuthi.cusat.ac.in/purl/1392 |
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Tunnel-based ar ... te microstrip antenna.PDF | (239.3Kb) |
Abstract: | Laser-induced plasma generated from a silver target under partial vacuum conditions using the fundamental output of nanosecond duration from a pulsed Nd:yttrium aluminum garnet laser is studied using a Langmuir probe. The time of flight measurements show a clear twin peak distribution in the temporal profile of electron emission. The first peak has almost the same duration as the laser pulse while the second lasts for several microseconds. The prompt electrons are energetic enough ('60 eV) to ionize the ambient gas molecules or atoms. The use of prompt electron pulses as sources for electron impact excitation is demonstrated by taking nitrogen, carbon dioxide, and argon as ambient gases. |
URI: | http://dyuthi.cusat.ac.in/purl/2393 |
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Dyuthi-P0202.pdf | (694.7Kb) |
Abstract: | Dual beam transient thermal lens studies were carried out in rhodamine 6G methanol solutions using 532 nm pulses from a frequency doubled Nd:YAG laser. Analysis of thermal lens signal shows the existence of different nonlinear processes like two photon absorption and three photon absorption phenomena along with one photon absorption. Concentration of the dye in the solution has been found to influence the occurrence of the different processes in a significant way. |
URI: | http://dyuthi.cusat.ac.in/purl/2611 |
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Dyuthi-P0171.pdf | (421.5Kb) |
Abstract: | Large amplitude local density fluctuations in a thin superfluid He film is considered. It is shown that these large amplitude fluctuations travel and behave like "quasi-solitons" under collision, even when the full nonlinearity arising from the Van der Waals potential is taken into account. |
URI: | http://dyuthi.cusat.ac.in/purl/2566 |
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Dyuthi-P0125.pdf | (299.5Kb) |
Abstract: | Despite its recognized value in detecting and characterizing breast disease, X-ray mammography has important limitations that motivate the quest for alternatives to augment the diagnostic tools that are currently available to the radiologist. The rationale for pursuing electromagnetic methods are based on the significant dielectric contrast between normal and cancerous breast tissues, when exposed to microwaves. The present study analyzes two-dimensional microwave tomographic imaging on normal and malignant breast tissue samples extracted by mastectomy, to assess the suitability of the technique for early detection ofbreast cancer. The tissue samples are immersed in matching coupling medium and are illuminated by 3 GHz signal. 2-D tomographic images ofthe breast tissue samples are reconstructed from the collected scattered data using distorted Born iterative method. Variations of dielectric permittivity in breast samples are distinguishable from the obtained permittivity profiles, which is a clear indication of the presence of malignancy. Hence microwave tomographic imaging is proposed as an alternate imaging modality for early detection ofbreast cancer. |
URI: | http://dyuthi.cusat.ac.in/purl/2739 |
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Dyuthi-P00373.pdf | (1.186Mb) |
Abstract: | Anti-lipopolysaccharide factors (ALFs), a type of cationic antimicrobial peptides (AMPs), and their derivatives are becoming predominant candidates for potential drugs in viral and bacterial diseases. This study reports the first ALF from the mud crab Scylla tranquebarica (StALF, JQ899453) and the second ALF isoform from the blue swimmer crab Portunus pelagicus (PpALF2, JQ899452). Both sequences encoded for precursor molecules, starting with a signal peptide containing 26 amino acid residues, followed by a highly cationic mature peptide, containing two conserved cysteine residues flanking a putative lipopolysaccharide (LPS)-binding domain. BLAST analysis revealed that both PpALF2 and StALF exhibited significant similarity with crustacean ALF sequences. The predicted molecular mass of the mature ALFs was 11.2 kDa with an estimated pI of 10.0. PpALF2 and StALF also showed the typical pattern of alternating hydrophobic and hydrophilic residues in their putative disulphide loop, suggesting that they comprise the same functional domain. Phylogenetic analysis showed that PpALF2 and StALF have similar evolutionary status and they were phylogenetically ancient immune effector molecules which may play an essential role in the host defense mechanism. The spatial structures of PpALF2 and StALF possessed four beta-strands and two alpha-helices. The results indicated that there were more than one ALF involved in crab immunity against various pathogens. ALFs would provide candidate promising therapeutic or prophylactic agents in health management and diseases control in crustacean aquaculture |
Description: | Molecular Immunology 52 (2012) 258– 263 |
URI: | http://dyuthi.cusat.ac.in/purl/4065 |
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Two isoforms of ... d Scylla tranquebarica.pdf | (1.310Mb) |
Abstract: | Two new clam shrimp species belonging to the genera Eulimnadia Packard, 1874 and Leptestheria Sars 1898 from Kerala, India are described. Spinicaudatan clam shrimp are among the least studied groups in India, with only 30 species reported. Eulimnadia azisi sp. nov. was collected from rain fed, temporary, rocky depressions at Vettilapara, in Western Ghats, Kerala. No males were observed and the population may be hermaphroditic. Leptestheria dumonti sp. nov. was collected from the paddy fields at Parapukara, Kerala. Altogether two species of Leptestheria and nine species of Eulimnadia have been reported from India, and this is the first report of the genus Leptestheria from Kerala. |
Description: | Zootaxa 2713: 55–64 (2010) |
URI: | http://dyuthi.cusat.ac.in/purl/4444 |
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Two new clam sh ... ata)from Kerala, India.pdf | (24.48Kb) |
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