Abstract: | Ionic polymers (ionomers) with interesting characteristics are emerging as important commercial polymers. Ionomers have the unique ability to behave as cross-linked materials at ambient temperatures and to melt and flow at elevated temperatures like thermoplastics. The complex permittivity and conductivity of a class of ionomers at microwave frequencies are determined using the cavity perturbation technique and the results are presented. |
URI: | http://dyuthi.cusat.ac.in/purl/2984 |
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Dyuthi-P00421.pdf | (128.1Kb) |
Abstract: | Permittivity and conductivity studies of corn syrup in various concentrations are performed using coaxial cavity perturbation technique over a frequency range of 250 MHz–3000 MHz. The results are utilized to estimate relaxation time and dipole moments of the samples. The stability of the material over the variations of time is studied. The measured specific absorption rate of the material complies with the microwave power absorption rate of biological tissues. This suggests the feasibility of using corn syrup as a suitable, cost effective coupling medium for microwave breast imaging. The material can also be used as an efficient breast phantom in microwave breast imaging studies. |
URI: | http://dyuthi.cusat.ac.in/purl/2738 |
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Dyuthi-P00372.pdf | (196.2Kb) |
Abstract: | Phantoms that exhibit complex dielectric properties similar to low water content biological tissues over the electromagnetic spectrum of 2–3 GHz have been synthesized from carbon black powder, graphite powder and polyvinyl-acetate-based adhesive. The materials overcome various problems that are inherent in conventional phantoms such as decomposition and deterioration due to the invasion of bacteria or mold. The absorption coefficients of the materials for various compositions of carbon black and graphite powder are studied. A combination of 50% polyvinylacetate- based adhesive, 20% carbon black powder and 30% graphite powder exhibits high absorption coefficient, which suggests another application of the material as good microwave absorber for interior lining of tomographic chamber in microwave imaging. Cavity perturbation technique is adopted to study the dielectric properties of the material. |
URI: | http://dyuthi.cusat.ac.in/purl/2736 |
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Dyuthi-P00370.pdf | (253.3Kb) |
Abstract: | The resurgence of the enteric pathogen Vibrio cholerae, the causative organism of epidemic cholera, remains a major health problem in many developing countries like India. The southern Indian state of Kerala is endemic to cholera. The outbreaks of cholera follow a seasonal pattern in regions of endemicity. Marine aquaculture settings and mangrove environments of Kerala serve as reservoirs for V. cholerae. The non-O1/non-O139 environmental isolates of V. cholerae with incomplete ‘virulence casette’ are to be dealt with caution as they constitute a major reservoir of diverse virulence genes in the marine environment and play a crucial role in pathogenicity and horizontal gene transfer. The genes coding cholera toxin are borne on, and can be infectiously transmitted by CTXΦ, a filamentous lysogenic vibriophages. Temperate phages can provide crucial virulence and fitness factors affecting cell metabolism, bacterial adhesion, colonization, immunity, antibiotic resistance and serum resistance. The present study was an attempt to screen the marine environments like aquafarms and mangroves of coastal areas of Alappuzha and Cochin, Kerala for the presence of lysogenic V. cholerae, to study their pathogenicity and also gene transfer potential. Phenotypic and molecular methods were used for identification of isolates as V. cholerae. The thirty one isolates which were Gram negative, oxidase positive, fermentative, with or without gas production on MOF media and which showed yellow coloured colonies on TCBS (Thiosulfate Citrate Bile salt Sucrose) agar were segregated as vibrios. Twenty two environmental V. cholerae strains of both O1 and non- O1/non-O139 serogroups on induction with mitomycin C showed the presence of lysogenic phages. They produced characteristic turbid plaques in double agar overlay assay using the indicator strain V. cholerae El Tor MAK 757. PCR based molecular typing with primers targeting specific conserved sequences in the bacterial genome, demonstrated genetic diversity among these lysogen containing non-O1 V. cholerae . Polymerase chain reaction was also employed as a rapid screening method to verify the presence of 9 virulence genes namely, ctxA, ctxB, ace, hlyA, toxR, zot,tcpA, ninT and nanH, using gene specific primers. The presence of tcpA gene in ALPVC3 was alarming, as it indicates the possibility of an epidemic by accepting the cholera. Differential induction studies used ΦALPVC3, ΦALPVC11, ΦALPVC12 and ΦEKM14, underlining the possibility of prophage induction in natural ecosystems, due to abiotic factors like antibiotics, pollutants, temperature and UV. The efficiency of induction of prophages varied considerably in response to the different induction agents. The growth curve of lysogenic V. cholerae used in the study drastically varied in the presence of strong prophage inducers like antibiotics and UV. Bacterial cell lysis was directly proportional to increase in phage number due to induction. Morphological characterization of vibriophages by Transmission Electron Microscopy revealed hexagonal heads for all the four phages. Vibriophage ΦALPVC3 exhibited isometric and contractile tails characteristic of family Myoviridae, while phages ΦALPVC11 and ΦALPVC12 demonstrated the typical hexagonal head and non-contractile tail of family Siphoviridae. ΦEKM14, the podophage was distinguished by short non-contractile tail and icosahedral head. This work demonstrated that environmental parameters can influence the viability and cell adsorption rates of V. cholerae phages. Adsorption studies showed 100% adsorption of ΦALPVC3 ΦALPVC11, ΦALPVC12 and ΦEKM14 after 25, 30, 40 and 35 minutes respectively. Exposure to high temperatures ranging from 50ºC to 100ºC drastically reduced phage viability. The optimum concentration of NaCl required for survival of vibriophages except ΦEKM14 was 0.5 M and that for ΦEKM14 was 1M NaCl. Survival of phage particles was maximum at pH 7-8. V. cholerae is assumed to have existed long before their human host and so the pathogenic clones may have evolved from aquatic forms which later colonized the human intestine by progressive acquisition of genes. This is supported by the fact that the vast majority of V. cholerae strains are still part of the natural aquatic environment. CTXΦ has played a critical role in the evolution of the pathogenicity of V. cholerae as it can transmit the ctxAB gene. The unusual transformation of V. cholerae strains associated with epidemics and the emergence of V. cholera O139 demonstrates the evolutionary success of the organism in attaining greater fitness. Genetic changes in pathogenic V. cholerae constitute a natural process for developing immunity within an endemically infected population. The alternative hosts and lysogenic environmental V. cholerae strains may potentially act as cofactors in promoting cholera phage ‘‘blooms’’ within aquatic environments, thereby influencing transmission of phage sensitive, pathogenic V. cholerae strains by aquatic vehicles. Differential induction of the phages is a clear indication of the impact of environmental pollution and global changes on phage induction. The development of molecular biology techniques offered an accessible gateway for investigating the molecular events leading to genetic diversity in the marine environment. Using nucleic acids as targets, the methods of fingerprinting like ERIC PCR and BOX PCR, revealed that the marine environment harbours potentially pathogenic group of bacteria with genetic diversity. The distribution of virulence associated genes in the environmental isolates of V. cholerae provides tangible material for further investigation. Nucleotide and protein sequence analysis alongwith protein structure prediction aids in better understanding of the variation inalleles of same gene in different ecological niche and its impact on the protein structure for attaining greater fitness of pathogens. The evidences of the co-evolution of virulence genes in toxigenic V. cholerae O1 from different lineages of environmental non-O1 strains is alarming. Transduction studies would indicate that the phenomenon of acquisition of these virulence genes by lateral gene transfer, although rare, is not quite uncommon amongst non-O1/non-O139 V. cholerae and it has a key role in diversification. All these considerations justify the need for an integrated approach towards the development of an effective surveillance system to monitor evolution of V. cholerae strains with epidemic potential. Results presented in this study, if considered together with the mechanism proposed as above, would strongly suggest that the bacteriophage also intervenes as a variable in shaping the cholera bacterium, which cannot be ignored and hinting at imminent future epidemics. |
Description: | Microbial Genetics laboratory, Department of Biotechnology |
URI: | http://dyuthi.cusat.ac.in/purl/5032 |
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Dyuthi-T2100.pdf | (5.569Mb) |
Abstract: | Three species of cephalopod molluacs collected from the waters in and around cochin area of the Arabian Sea, of south India formed the subject of the present study. The Species are loligo duvauceli, _Sepia_ aculeata and sepiella inermis, their food and feeding habits, morphology and histology of the gut as well as the physiology of digestion have been described |
Description: | Department of Marine Science, Cochin University of Science & Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3344 |
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Dyuthi-T1326.pdf | (4.763Mb) |
Abstract: | The purpose of this study was to identify the digital curation practices in Institutional Repositories (IRs) in South India. A voluntary survey was conducted among the IR managers of 23 South Indian IRs, and the response rate was 87%. This study found that the active participation of South Indian IRs was only seen in a few digital curation activities. However, Of the 33 digital curation activities analyzed, the active participation of IRs was only seen in ten digital curation activities. The performance of preservation activities was extremely low, and disagreements were recorded by the survey participants towards several digital curation activities. The most disagreed digital curation activities were emulation and cease data curation. All the participants had assigned metadata and allowed file download in their IRs. Raman Research Institute had provided a good number of digital curation services in their IR. This is an in-depth study investigating the digital curation practice currently underway in South Indian IRs, and the researcher could not find similar studies in this niche. Emerald allows authors to deposit their AAM under the Creative Commons Attribution Non-commercial International Licence 4.0 (CC BY-NC 4.0). |
URI: | https://doi.org/10.1108/GKMC-10-2019-0125 |
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Shajitha.docx | (182.5Kb) |
Abstract: | Digital library Initiatives in India, models of electronic and print publishing, digitallibrary and funding, chaalenges and oppertunities,digital ibrary initiatives in India, current digital library moedels etc |
URI: | http://dyuthi.cusat.ac.in/purl/1525 |
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DLIMMNEW.PPT | (3.980Mb) |
Abstract: | Long Term Digital Preservation (LTDP) is a secure and trustworthy mechanism to ingest, process, store, manage, protect, find, access, and interpret digital information such that the same information can be used at some arbitrary point in the future in spite of obsolescence of everything: hardware, software, processes, format, people, etc |
Description: | Digital Preservation - Challenges. DigitalLibrary@CUSAT |
URI: | http://dyuthi.cusat.ac.in/purl/4149 |
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Digital Preservation - Challenges.pdf | (10.77Mb) |
Abstract: | Hindi |
Description: | Departrnent of Hindi, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/4839 |
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Dyuthi-T1936.pdf | (3.961Mb) |
Abstract: | HINDI |
Description: | DEPARTMENT OF HINDI COCHIN UNIVERSITY OF SCIENCE AND TECHNOLOGY |
URI: | http://dyuthi.cusat.ac.in/purl/4753 |
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Dyuthi-T1850.pdf | (6.545Mb) |
Abstract: | The direction dependant wavelength selective transmission mechanism in poly (methyl methacrylate)(PMMA) rods doped with C 540 dye and C 540:Rh.B dye mixture as a combination has been investigated. When a polished slice of pure C 540 doped polymer rod was used side by side with a C540:Rh B doped rod with acceptor concentration [A] = 7x10-4 m/l , we could notice more than 100% change in the transmitted intensity along opposite directions at the C 540, Rh B emission and the excitation wavelengths . A blue high bright LED emitting at a peak wavelength 465nm was used as the excitation source. |
URI: | http://dyuthi.cusat.ac.in/purl/1775 |
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DIRECTION DEPEN ... CHARACTERISTICS OF DYE.pdf | (695.3Kb) |
Abstract: | The direction dependant wavelength selective transmission mechanism in poly (methyl methacrylate)(PMMA) rods doped with C 540 dye and C 540:Rh.B dye mixture as a combination has been investigated. When a polished slice of pure C 540 doped polymer rod was used side by side with a C540:Rh B doped rod with acceptor concentration [A] = 7x10-4 m/l , we could notice more than 100% change in the transmitted intensity along opposite directions at the C 540, Rh B emission and the excitation wavelengths . A blue high bright LED emitting at a peak wavelength 465nm was used as the excitation source. |
URI: | http://dyuthi.cusat.ac.in/purl/1774 |
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DIRECTION DEPEN ... CHARACTERISTICS OF DYE.pdf | (695.3Kb) |
Abstract: | The direction dependant wavelength selective transmission mechanism in poly (methyl methacrylate)(PMMA) rods doped with C 540 dye and C 540:Rh.B dye mixture as a combination has been investigated. When a polished slice of pure C 540 doped polymer rod was used side by side with a C540:Rh B doped rod with acceptor concentration [A] = 7x10-4 m/l , we could notice more than 100% change in the transmitted intensity along opposite directions at the C 540, Rh B emission and the excitation wavelengths . A blue high bright LED emitting at a peak wavelength 465nm was used as the excitation source. |
URI: | http://dyuthi.cusat.ac.in/purl/1825 |
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DIRECTION DEPEN ... CHARACTERISTICS OF DYE.pdf | (695.3Kb) |
URI: | http://dyuthi.cusat.ac.in/purl/5451 |
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Dyuthi T-2492.pdf | (35.50Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/1027 |
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Thresiamma T k 1986.pdf | (257.9Kb) |
Abstract: | The object of this thesis is to formulate a basic commutative difference operator theory for functions defined on a basic sequence, and a bibasic commutative difference operator theory for functions defined on a bibasic sequence of points, which can be applied to the solution of basic and bibasic difference equations. in this thesis a brief survey of the work done in this field in the classical case, as well as a review of the development of q~difference equations, q—analytic function theory, bibasic analytic function theory, bianalytic function theory, discrete pseudoanalytic function theory and finally a summary of results of this thesis |
Description: | Department of Mathematics and Statistics, Cochin University of Science & Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3341 |
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Dyuthi-T1325.pdf | (3.438Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/5427 |
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Dyuthi T-2468.pdf | (2.089Mb) |
Abstract: | In everyday life different flows of customers to avail some service facility or other at some service station are experienced. In some of these situations, congestion of items arriving for service, because an item cannot be serviced Immediately on arrival, is unavoidable. A queuing system can be described as customers arriving for service, waiting for service if it is not immediate, and if having waited for service, leaving the system after being served. Examples Include shoppers waiting in front of checkout stands in a supermarket, Programs waiting to be processed by a digital computer, ships in the harbor Waiting to be unloaded, persons waiting at railway booking office etc. A queuing system is specified completely by the following characteristics: input or arrival pattern, service pattern, number of service channels, System capacity, queue discipline and number of service stages. The ultimate objective of solving queuing models is to determine the characteristics that measure the performance of the system |
Description: | Department of Mathematics, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3210 |
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Dyuthi-T1184.pdf | (506.5Kb) |
Abstract: | This paper compares the most common digital signal processing methods of exon prediction in eukaryotes, and also proposes a technique for noise suppression in exon prediction. The specimen used here which has relevance in medical research, has been taken from the public genomic database - GenBank.Here exon prediction has been done using the digital signal processing methods viz. binary method, EIIP (electron-ion interaction psuedopotential) method and filter methods. Under filter method two filter designs, and two approaches using these two designs have been tried. The discrete wavelet transform has been used for de-noising of the exon plots.Results of exon prediction based on the methods mentioned above, which give values closest to the ones found in the NCBI database are given here. The exon plot de-noised using discrete wavelet transform is also given.Alterations to the proven methods as done by the authors, improves performance of exon prediction algorithms. Also it has been proven that the discrete wavelet transform is an effective tool for de-noising which can be used with exon prediction algorithms |
Description: | BMC Bioinformatics 2010, 11(Suppl 1):S50 |
URI: | http://dyuthi.cusat.ac.in/purl/4571 |
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Discrete wavele ... karyotic gene splicing.pdf | (2.558Mb) |
Abstract: | This is a study in labour law.. Dismissal of workmen in private lndustrial sector is the area of this study. Confined within the framework of the Industrial Disputes act 1947, the study is an analytical assessment of the decisions of the supreme Court of India. on dismissal in industrial employment. Few attempts were made in the past to analyse on identical lines the problems in this area. Hence what is| written in this thesis is ones own. Dismissal carries a stigma. the dismissed employee may find it difficult to get alternative employment especially in a land of severe unemployment. The need for law with built in safeguards against arbitrary dismissal cannot be overemphasized. From this perspective the study examines to what extent the industrial disputes act 1947 provides protection and how far the protection is adequate. |
Description: | School of legal studies, Cochin University of Science And Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3343 |
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Dyuthi-T1304.pdf | (29.53Mb) |
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