Boban, Thomas; Dr.Krishna Pillai, M G(Cochin University of Science and Technology, December , 1989)
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Abstract:
This thesis deals with preparing stoichiometric crystalline thin films of InSe and In2Se3 by elemental evapouration and their property investigation.In the present study three temperature( or Elemental evapouration) method is utilized for the deposition of crystalline thin films . The deposition mechanism using three temperature method deals’ with condensation of solids on heated surfaces when the critical supersaturation of the vapour phase exceeds a certain limit. The critical values of the incident flux are related to substrate temperature and the interfacial energies of the involved vapours. At a favorable presence of component atoms in the vapour phase these can react and condense onto a substrate even at a elevated temperature. In the studies conducted the most significant factor is the formation of single compositional film namely indium mono selenide in the In –se system of compounds .Further this work shows the feasibility of thin film photovoltaic junctions of the schottky barrier type
Description:
Department of Physics, Cochin University of Science and Technology
Mohanachandran, K; Dr.Sathianandan, K(Cochin University Of Science And Technology, April 2, 1983)
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Abstract:
Due to the great versatility of the properties
of polymer thin films, special interest has been taken in
recent years on their preparation and electrical properties.
The present thesis is entirely devoted to the study of the
formation, structure and electrical properties of plasma»
polymerised polyacrylonitrile (PAN) thin films. Eventhough
the studies are confined to a single polymer film, the
results in general are applicable to similar polar polymer
films.
Description:
Department of Physics,Cochin University Of Science And Technology
Mohanan, P; Dr.Nair, K G(Cochin University of Science And Technology, March , 1985)
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Abstract:
The flange technique, suggested by Reynolds72
is simple technique to improve antenna characteristics.
Using flange technique we can trim the antenna
characteristic by suitably adjusting the flange parameters75.
Later corrugated flanges87 are used for beam shaping. The
important parameters of the corrugated flanges are (a) flange
angle, (b) flange width, (c) flange position, (d) conductivity
of the flange, (e) amplitude excitation of the flange
elements, (f) period of corrugation etc. Compared to a
compound horn the flange technique offers great convenience
in trimming antenna characteristics.
Horns are commonly used as a feed in radar and
satellite communications. A large number of work had been
done to improve the characteristics of horn antennas. It is
an established fact that grooved walls on the inner surface
of a horn can improve the antenna characteristics44.
Corrugated comb surface can be used for the circular
polarization98, tilt of polarization99 etc. This suggests
the possibility to combine these two phenomena and to
obtain a resultant beam. This thesis presents the result
of an investigation to study the possibility of controlling
different antenna characteristics like polarization, beam
shaping, matching etc, using corrugated flange techniques.
Description:
Department of physics, Cochin University of Science And Technology
Deepa, Sankar; Dr. Tessamma, Thomas(Cochin University of Science and Technology, August , 2011)
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Abstract:
After skin cancer, breast cancer accounts for the second greatest number of cancer diagnoses in women. Currently the etiologies of breast cancer are unknown, and there is no generally accepted therapy for preventing it. Therefore, the best way to improve the prognosis for breast cancer is early detection and treatment. Computer aided detection systems (CAD) for detecting masses or micro-calcifications in mammograms have already been used and proven to be a potentially powerful tool , so the radiologists are attracted by the effectiveness of clinical application of CAD systems. Fractal geometry is well suited for describing the complex physiological structures that defy the traditional Euclidean geometry, which is based on smooth shapes. The major contribution of this research include the development of
• A new fractal feature to accurately classify mammograms into normal and normal (i)With masses (benign or malignant) (ii) with microcalcifications (benign or malignant)
• A novel fast fractal modeling method to identify the presence of microcalcifications by fractal modeling of mammograms and then subtracting the modeled image from the original mammogram.
The performances of these methods were evaluated using different standard statistical analysis methods. The results obtained indicate that the developed methods are highly beneficial for assisting radiologists in making diagnostic decisions. The mammograms for the study were obtained from the two online databases namely, MIAS (Mammographic Image Analysis Society) and DDSM (Digital Database for Screening Mammography.
Description:
Department of Electronics, Cochin University of Science and Technology
Assia,N V; Thrivikraman,T(Department of Mathematics, 2002)
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Abstract:
The study on the fuzzy absolutes and related topics. The different kinds of extensions especially compactification formed a major area of study in topology. Perfect continuous mappings always preserve certain topological properties. The concept of Fuzzy sets introduced by the American Cyberneticist L. A Zadeh started a revolution in every branch of knowledge and in particular in every branch of mathematics. Fuzziness is a kind of uncertainty and uncertainty of a symbol lies in the lack of well-defined boundaries of the set of objects to which this symbol belongs. Introduce an s-continuous mapping from a topological space to a fuzzy topological space and prove that the image of an H-closed space under an s-continuous mapping is f-H closed. Here also proved that the arbitrary product
fi and sum of fi of the s-continuous maps fi are also s-continuous. The original motivation behind the study of absolutes was the problem of characterizing the projective objects in the category of compact spaces and continuous functions.
Sunil,Jacob John; Thrivikraman,T(Department of Mathematics,Faculty of Science, 2000)
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Abstract:
The main purpose of study is to extend the concept of the topological game G(K, X) and some other kinds of games into fuzzy topological games and to obtain some results regarding them. Owing to the fact that topological games have plenty of applications in covering properties, it made an attempt to explore some inter relations of games and covering properties in fuzzy topological spaces. Even though the main focus is on fuzzy para-meta compact spaces and closure preserving shading families, some brief sketches regarding fuzzy P-spaces and Shading Dimension is also provided. In a topological game players choose some objects related to the topological structure of a space such as points, closed subsets, open covers etc. More over the condition on a play to be winning for a player may also include topological notions such as closure, convergence, etc. It turns out that topological games are related to the Baire property, Baire spaces, Completeness properties, Convergence properties, Separation properties, Covering and Base properties, Continuous images, Suslin sets, Singular spaces etc.
Balarama Kaimal,S; Dr. Paulose, C S(Cochin University of Science & Technology, July , 2005)
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Abstract:
The present study demonstrate the functional alterations of the GABAA and GABAB
receptors and the gene expression during the regeneration of pancreas following
partial pancreatectomy. The role of these receptors in insulin secretion and
pancreatic DNA synthesis using the specific agonists and antagonists also are studied
in vitro. The alterations of GABAA and GABAR receptor function and gene
expression in the brain stem, crebellum and hypothalamus play an important role in
the sympathetic regulation of insulin secretion during pancreatic regeneration.
Previous studies have given much information linking functional interaction between
GABA and the peripheral nervous system. The involvement of specific receptor
subtypes functional regulation during pancreatic regeneration has not given emphasis
and research in this area seems to be scarce. We have observed a decreased GABA
content, down regulation of GABAA receptors and an up regulation of GABAB
receptors in the cerebral cortex, brain stem and hypothalamus. Real Time-PCR
analysis confirmed the receptor data in the brain regions. These alterations in the
GABAA and GABAB receptors of the brain are suggested to govern the regenerative
response and growth regulation of the pancreas through sympathetic innervation. In
addition, receptor binding studies and Real Time-PCR analysis revealed that during
pancreatic regeneration GABAA receptors were down regulated and GABAB
receptors were up regulated in pancreatic islets. This suggests an inhibitory role for
GABAA receptors in islet cell proliferation i.e., the down regulation of this receptor
facilitates proliferation. Insulin secretion study during 1 hour showed GABA has
inhibited the insulin secretion in a dose dependent manner in normal and
hyperglycaemic conditions. Bicuculline did not antagonize this effect. GABAA
agonist, muscimol inhibited glucose stimulated insulin secretion from pancreatic
islets except in the lowest concentration of 1O-9M in presence of 4mM glucose.Musclmol enhanced insulin secretion at 10-7 and 10-4M muscimol in presence of
20mM glucose- 4mM glucose represents normal and 20mM represent
hyperglycaemic conditions. GABAB agonist, baclofen also inhibited glucose induced
insulin secretion and enhanced at the concentration of 1O-5M at 4mM glucose and at
10-9M baclofen in presence of 20mM glucose. This shows a differential control of
the GABAA and GABAB receptors over insulin release from the pancreatic islets.
During 24 hours in vitro insulin secretion study it showed that low concentration of
GABA has inhibited glucose stimulated insulin secretion from pancreatic islets.
Muscimol, the GABAA agonist, inhibited the insulin secretion but, gave an enhanced
secretion of insulin in presence of 4mM glucose at 10-7
, 10-5 and 1O-4M muscimol.
But in presence of 20mM glucose muscimol significantly inhibited the insulin
secretion. GABAB agonist, baclofen also inhibited glucose induced insulin secretion
in presence of both 4mM and 20mM glucose. This shows the inhibitory role of
GABA and its specific receptor subtypes over insulin synthesis from pancreatic bete-islets.
In vitro DNA synthesis studies showed that activation of GABAA receptor by
adding muscimol, a specific agonist, inhibited islet DNA synthesis. Also, the
addition of baclofen, a specific agonist of GABAB receptor resulted in the stimulation
of DNA synthesis.Thus the brain and pancreatic GABAA and GABAB receptor
gene expression differentially regulates pancreatic insulin secretion and islet cell
proliferation during pancreatic regeneration. This will have immense clinical
significance in therapeutic applications in the management of Diabetes mellitus.
Description:
Department of Biotechnology,
Cochin University of Science and Technology
Jobin, Mathew; Dr. Paulose, C S(Cochin University of Science and Technology, March 11, 2010)
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Abstract:
The research work which was carried out to characterization of wastes from natural rubber and rubber wood processing industries and their utilization for biomethanation. Environmental contamination is an inevitable consequence of human activity. The liquid and solid wastes from natural rubber based industries were: characterized and their use for the production of biogas investigated with a view to conserve conventional energy, and to mitigate environmental degradation.Rubber tree (flevea brasiliensis Muell. Arg.), is the most important commercial source of natural rubber and in india. Recently, pollution from the rubber processing factories has become very serious due to the introduction of modern methods and centralized group processing practices.The possibility of the use of spent slurry as organic manure is discussed.l0 percent level of PSD, the activity of cellulolytic, acid producing,proteolytic, lipolytic and methanogenic bacteria were more in the middle stage of methanogenesis.the liquid wastes from rubber processing used as diluents in combination with PSD, SPE promoted more biogas production with high methane content in the gas.The factors that favour methane production like TS, VS, cellulose and hemicellulose degradation were favoured in this treatment which led to higher methane biogenesis.The results further highlight ways and means to use agricultural wastes as alternative sources of energy.
Description:
Department of Biotechnology, Cochin University of Science and Technology
Shilpa, Joy; Dr. Paulose, C S(Cochin University of Science And Technology, July , 2013)
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Abstract:
Nanoparticulate drug delivery systems provide wide opportunities for
solving problems associated with drug stability or disease states and create great
expectations in the area of drug delivery (Bosselmann & Williams, 2012).
Nanotechnology, in a simple way, explains the technology that deals with one
billionth of a meter scale (Ochekpe, et al., 2009). Fewer side effects, poor
bioavailability, absorption at intestine, solubility, specific delivery to site of action
with good pharmacological efficiency, slow release, degradation of drug and
effective therapeutic outcome, are the major challenges faced by most of the drug
delivery systems. To a great extent, biopolymer coated drug delivery systems
coupled with nanotechnology alleviate the major drawbacks of the common
delivery methods. Chitosan, deacetylated chitin, is a copolymer of β-(1, 4) linked
glucosamine (deacetylated unit) and N- acetyl glucosamine (acetylated unit)
(Radhakumary et al., 2005). Chitosan is biodegradable, non-toxic and bio
compatible. Owing to the removal of acetyl moieties that are present in the amine
functional groups of chitin, chitosan is readily soluble in aqueous acidic solution.
The solubilisation occurs through the protonation of amino groups on the C-2
position of D-glucosamine residues whereby polysaccharide is converted into
polycation in acidic media. Chitosan interacts with many active compounds due to
the presence of amine group in it. The presence of this active amine group in
chitosan was exploited for the interaction with the active molecules in the present
study. Nanoparticles of chitosan coupled drugs are utilized for drug delivery in
eye, brain, liver, cancer tissues, treatment of spinal cord injury and infections
(Sharma et al., 2007; Li, et a., 2009; Paolicelli et al., 2009; Cho et al., 2010). To
deliver drugs directly to the intended site of action and to improve
pharmacological efficiency by minimizing undesired side effects elsewhere in the
body and decrease the long-term use of many drugs, polymeric drug delivery
systems can be used (Thatte et al., 2005).
Description:
Department of Biotechnology, Cochin University of Science and Technology
Biju,M P; Paulose,C S(Department of Biotechnology, 2000)
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Abstract:
The present thesis is an attempt to understand the role of GABA, GABAA and GABAB receptors in the regulation of liver cell proliferation using in vivo and in vitro models. The work also focuses on the brain GABAergic changes associated with normal and neoplastic cell growth in liver and to delineate its regulatory function. The investigation of mechanisms involving mitogenic models without cell necrosis may contribute our knowledge about both on cell growth, carcinogenesis, liver pathology and treatment. Objectives of the present study are, to induce controlled liver cell proliferation by partial hepatectomy and lead nitrate administration and uncontrolled cell proliferation by N-nitrosodiethylamine treatment in male Wistar rats, the changes in the content of GABA, GABAA,GABAB in various rat brain regions. To study the GABAA and GABAB receptor changes in brain stem, hypothalamus, cerebellum and cerebral cortex during the active cortex during the period of active DNA synthesis in liver of different experimental groups. The changes in GABAA and GABAB receptor function of the brain stem, hypothalamus and cerebellum play an important role sympathetic regulation of cell proliferation and neoplastic growth in liver. The decrease in GABA content in brain stem, hypothalamus and cerebellum during regeneration and neoplasia in liver. The time course of brain GABAergic changes was closely correlated with that of heptic DNA synthesis. The functional significance of these changes was further explored by studying the changes in GABAA and GABAB receptors in brain.
Anju, T R; Dr. Paulose, C S(Cochin University of Science and Technology, September , 2010)
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Abstract:
The present study was designed to investigate the protective effect of
glucose, oxygen and epinephrine resuscitation on impairment in the functional role
of GABAergic, serotonergic, muscarinic receptors, PLC, BAX, SOD, CAT and
GPx expression in the brain regions of hypoxia induced neonatal rats. Also, the
role of hormones - Triiodothyronine (T3) and insulin, second messengers –
cAMP, cGMP and IP3 and transcription factors – HIF and CREB in the regulation
of neonatal hypoxia and its resuscitation methods were studied. Behavioural
studies were conducted to evaluate the motor function and cognitive deficit in one
month old control and experimental rats. The efficient and timely supplementation
of glucose plays a crucial role in correcting the molecular changes due to hypoxia,
oxygen and epinephrine. The sequence of glucose, epinephrine and oxygen
administration at the molecular level is an important aspect of the study. The
additive neuronal damage effect due to oxygen and epinephrine treatment is
another important observation. The corrective measures by initial supply of
glucose to hypoxic neonatal rats showed from the molecular study when brought
to practice will lead to healthy intellectual capacity during the later developmental
stages, which has immense clinical significance in neonatal care.
Description:
Department of Biotechnology,
Cochin University of Science and Technology