Virinder,Moudgil; Vera,Kruczak; Thomas,Eessalu; Paulose,C S; Michael,Taylor; Jeffrey,Hansen(Department of Biotechnology, May 14, 1981)
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Abstract:
Progesterone-receptor complex from freshly prepared hen oviduct cytosol acquired the ability to bind to
isolated nuclei, DNA-cellulose and ATP-Sepharose when incubated with 5-10 mM ATP at 4°C. The extent of
this ATP-dependent activation was higher when compared with heat-activation achieved by warming the progesterone-
receptor complex at 23 °C. The transformation of progesterone-receptor complex which occurred in a
time-dependent manner was only partially dependent on hormone presence. The ATP effect was selective in
causing this transformation whereas ADP, AMP and cAMP failed to show any such effect. The non-hydrolizable
analogs of ATP, adenosine 5'-[a,/3-methylene]triphosphate and adenosine 5-[/l,y-imido]triphosphate were also
found to be ineffective. Presence of 10 mM sodium molybdate blocked both the ATP and the heat-activation of
progesterone-receptor complex. Mn" or Mg` had no detectable effect on the receptor activation but the presence
of Ca" increased the extent of ATP-activation slightly. EDTA presence (> 5 mM) decreased the extent of
receptor activation by about 40 % and was, therefore, not included in the buffers used for activation studies.
Divalent cations were also ineffective when tested in the presence of 1- 5 mM EDTA. The
properties of progesterone-receptor complex remained intact under the above conditions when analyzed for
steroid-binding specificity and Scatchard analysis. However, the ATP-activated progesterone-receptor complex
lost the ability to aggregate when tested on low-salt sucrose gradients. ATP was equally effective in activating
the rat-uterine estradiol-receptor complex at 4 "C and influenced the transformation of 4-S receptor form into
a 5-S form when analyzed on sucrose gradients containing 0.3 M KCI. The presence of ATP also increased the
rate of activation of progesterone-receptor complex at 23 °C. These findings suggest a role for ATP in receptor
function and offer a convenient method of studying the process of receptor activation at low temperature and
mild assay conditions.
Subhash, N; Dr.Sathianandan, K(Cochin University of Science And Technology, August , 1981)
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Abstract:
Laser engineering is an area in which developments in the
existing design concepts and technology appear at an alarming rate.
Now—a-days, emphasis has shifted from innovation to cost reduction
and system improvement. To a major extent, these studies are aimed
at attaining larger power densities, higher system efficiency and
identification of new lasing media and new lasing wavelengths. Todate
researchers have put to use all the ditferent Forms of matter as lasing
material. Laser action was observed For the first time in a gaseous
system - the He-Ne system. This was Followed by a variety of solidstate
and gas laser systems. Uarious organic dyes dissolved in suitable
solvents were found to lase when pumped optically. Broad band
emission characteristics of these dye molecules made wavelength tuning
possible using optical devices. Laser action was also observed in
certain p-n junctions of semiconductor materials and some of these
systems are also tunable. The recent addition to this list was the
observation of laser action from certain laser produced plasmas.
The purpose of this investigation was to examine the design
and Fabrication techniques of pulsed Nitrogen lasers and high power
Nd: Glass laserso Attempt was also made to put the systems developed
into certain related experiments
Description:
Department of Physics, Cochin University of Science and Technology
Zachariah,E J; Dr.Nair, K G(Cochin University of Science And Technology, August , 1981)
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Abstract:
The need for improved feed systems for large reflector antennas employed in Radio Astronomy and Satellite tracking spurred the interest in horn antenna research in
the 1960's. The major requirements were to reduce spill over, cross-polarisation losses,and to enhance the aperture efficiency to the order of about 75-8O%L The search for such a feed culminated in the corrugated horn. The corrugat1e 1 horn triggered widespread interest and enthusiasm, and a large amount of work(32’34’49’5O’52’53’58’65’75’79)has already been done on this type of antennas. The properties of corrugated surfaces has been investigated in detail.
It was strongly felt that the flange technique and the use of corrugated surfaces could be merged together to obtain the advantages of both. This is the idea behind the present work. Corrugations are made on the surface of flange elements. The effect of various corrugation parameters are studied. By varying the flange parameters, a good amount of data is collected and analysed to ascertain the effects of corrugated flanges. The measurements are repeated at various frequencies, in the X— and S-bands. The following parameters of the system were studied: (a) beam shaping (b) gain (c) variation of V.S.U.R. (d) possibility of obtaining circularly polarised
radiation from the flanged horn. A theoretical explanation to the effects of corrugated flanges
is attempted on the basis of the line-source theory. Even though this theory utilises a simplified model for the calculation of radiation patterns, fairly good agreement between the computed pattern and experimental results are observed.
Description:
Department of physics, Cochin University of Science And Technology
Hridayanathan,C; Dr.Kurian, C V(Cochin University of Science and Technology, August , 1981)
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Abstract:
The present study was undsrtaken.with the objectives to assess the distribution and density of population of benthic animals with special reference to macrofauna from the south west coast of India from ' Malippursa 1 in the north to Alleppey in the south, to evaluate significant difference, if any, in the number and distribution of animals in th md bank regions and other intermittent stations, to examine the influence of bottom stability on the distribution of fauna, to observe the effect of the environmental parameters on the distribution pattern of nacrofauna, and to evaluate the nature and depthpwise distribution of the benthic fishery. The region selected for the investigation is one of the nest important fishing grounds in India for bottom fishing especially for prawns, covering a distance of about 60 kns in length.total number of thirty stations in five transects at right angles to the coast, each consisting of six stations were surveyed. The six stations in a transect were at depths of 5 m, 10m, 20:, 30:, 35m and 45m respectively formation of the Iudbanke, popularly known as 'Ghaknra' in the local language, is a peculiar phenomenon along the ooaet of Kerala and provides a good fishing ground.quantitative distribution of the mecrofauna chewed that the maximum number of organism was near the 35 n contour line in the first three profiles whereas in the fourth and fifth profiles it was at 20 n and 30 m depth respectively. The density of the fauna wee comparatively poor in shallow water etatione at depths 5-‘IO M.was a general decline in the numerical abundance and biomass of the bottom fauna in all the stations during the monsoon period. There has been very little yearly change in
the composition of the fauna during the two years‘ study.
Description:
Department of Marine Science, Cochin University of Science and Technology
Wilson, P R; Dr.Nair, K N(Cochin University of Science And Technology, October , 1981)
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Abstract:
Today India is seeking a speedy transformation of her semi-stagnant economy to a dynamic one by means of economic planning in a democratic set up. In the context of this growth oriented endeavour public sector has a vital role to play. After three decades of planned development,
it has become important that India must make fresh appraisals on the role of public sector in the economic renaissance of the country. Almost no comprehensive study has been made on
this vital segment of the economy vis-a-vis the growth economics. This study is an attempt to fill this need in a very modest way. It presents the subject in a new perspective. An earnest attempt is made to reveal the critical problems inhibiting the growth of the public sector from a new angle which focusses the spot-light on the economics of development.
Description:
School of management studies, Cochin University of Science And Technology
Thomas,Thomas P; Dr.George, Philip(Cochin University of Science And Technology, October , 1981)
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Abstract:
ac-qlncnn phosphorylsse is en ilportent enzyme in
glycoiysis. It is the first used knows to exhibit
ellosteric properties and lance its inhibition end
ectivetion have significant effect on the rete ot
qlycolysis. The thesis deals with 11 detailed study of
the structure. inhibition and control or this snlrlls
from rabbit uncle and troll e merino eninelo
‘the thesis is divided into two parts. Port 1
deals with studies on rabbit uncle glycogen phospherylese.
After e review of the relevant literetnre (Chapter 1) the
inhibition and chancel sodiiicetion studies on rabbit
ensyle ere discussed in chepters 2 to 5. Chapter 6. gives
the methods used for the study
Description:
School of Marine Sciences, Cochin University of Science and Technology
Sreedharan Nair, M N; Dr.Babu, Joseph K(Cochin University of Science and Technology, November 2, 1981)
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Abstract:
This thesis is devoted to theoretical studies on the properties of hadrons on the basis of bag models. It contains some applications of the traditional.HIT bag model to the spectroscopy and decay of hadrons. The inadequacies of the model are brought out and a new version of the model, called the variable pressure bag model, is developed. Some of the Phenomenological applications of this model are discussed and the predictions are compared with experiment.
Description:
Department of Physics, Cochin University of Science & Technology
Indrapal Singh,N; Shrivastaw,K P; Paulose,C S; Subba Rao,K(Department of Biotechnology, November 13, 1981)
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Abstract:
Acid and alkaline DNase activities in partially purified preparations from young and old chick brain were measured. The
specific activity of acid DNase from old brain was lower by about 50% than that of enzyme from young brain , whereas alkaline
DNase exhibited only marginal difference in activity of the two preparations . Study of various properties, viz. heat-stability
and effect of exogenous compounds like Mg=', Hgl', Zn=', PHM B , on these enzymes revealed that while acid DNase in old
brain is more susceptible to heat and heavy metal ion inhibition , alkaline DNase is devoid of any age-dependent variation in
its properties.
Sebastian, P J; Dr.Sathianandan, K(Cochin University Of Science And Technology, November 25, 1981)
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Abstract:
Eventhough a large number of schemes have been proposed and develoned for N9 laser ouined dye lasers the
relatively low efficiency compelled the scientists to
device new methods to improve the system efficiencs.
Energy transfer mechanism has been shown to he a convenien
tool for the enhancement of efficiency of dye lasers. Th
p resent work covers a detailed study of the performance
characteristics of a N2 laser pumped dye laser in the con—
ventional mode and also, when pumped by the energy transfer
mechanism. For .th.e present investigations a dye laser
pumped by a'N2 laser (A4200 kw peak power) was fabricated.
The grating at grazing incidence was used as the beam expanding
device; A t its best performance the system was
giving an output peak power of l5 kW for a 5 X lC"3H/l Rh—€
solution in methanol. T he conversion efficiency was 7.5;
The output beam was having 3 divergence of 2 mrad and bandwidth
o.9 A. Suitable modifications were suggested for
obtaining better conversion efficiency and bandwidth.
Description:
Department of Physics,
Cochin University Of Science And Technology
Saseendran Pillai, P R; Dr.Sreedhar, C S(Cochin University of Science and Technology, December , 1981)
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Abstract:
The thesis presented here includes the designing of underwater transducer arrays, taking into account the ‘interaction effects’ [30] among the closely packed radiators.
Methods of minimizing the ‘interaction effects‘ by modifying the radiating aperture, are investigated. The need for this study arises as it is one of the important peculiar limitations that stands in the way of achieving maximum range of transmission of acoustic signals. Application of the modified array format for the generation of narrow beam low frequency sound waves, through nonlinear interactions, is discussed. Other techniques that can be advantageously
exploited in array synthesis are also investigated
Description:
Department of electronics and communication systems, Cochin University of Science And Technology
Syamaprasad, U; Dr.Girijavallabhan,C P(Cochin University of Science And Technology, December , 1981)
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Abstract:
The thesis aims to present the results of the
experimental investigations on the electrical properties like
electrical conductivity, dielectric constant and ionic thermo~
currents in certain ammonium containing ferroelectric crystals
viz. LiNH4SO4, (NH4)2SO4 and (NH4)5H(SO4)2. Special attention
has been paid in revealing the mechanisms of electrical conduction
in the various phases of these crystals and those asso~
ciated with the different phase transitions occurring in them,
by making studies on doped, quenched and deuterated crystals.
The report on the observation of two new phase transitions in
(NH4) S O2 and of a similar one in ( NH4 ) H (2SO4 ) are included. The relaxation mechanisms of the impurity-vacancy complexes and the space charge phenomena in pure and doped crystals of LiNH4SO4 and (NH4)2SO4 and the observation of a new type of ionic thermo-current viz. Protonic Thermo-Current (PTC) in these crystals are also presented here.
Description:
Department of Physics, Cochin University of Science and Technology
Gopinathan,C P; Dr.Ramachandran Nair,P V(Cochin University of Science and Technology, December , 1981)
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Abstract:
This thesis deals with the results oi’
investigations on phytoplankton productivity and related
aspects conducted in various ecoaystms such as estuarine,
inshore and oceanic enviroments and certain special
ecosytans including the pu.-awn culture fields and associated
many-eves, mud bank and the seas around the Andaman-Nicobar
Islands. This study also includes the qualitative and
quantitative variations of phytoplankton production, their
seasonal abundance, factors controlling the same and the
magnitude of the potential resources derived 1!:-om it
Raveendran Nair, B; Dr.Joseph,Francis D(Cochin University of Science and Technology, December , 1981)
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Abstract:
Urea-formaldehyde resins find numerous
applications in adhesive, textile finishing and moulded
plastic industries. Kinetic investigations of the reactions of
urea and its related compounds with formaldehyde in
aqueous acid, alkaline and neutral media have been carried
out. A thin—layer chromatographic method was developed
for the separation and estimation of the products of these
reactions. Using this technique the various initial steps
in the reactions were analysed and the rate constants have been determined.
Description:
Department of Applied Chemistry, Cochin University of Science and Technology
Pravinkumar,P A; Mohanan, P; K G Nair(Indian Journal of Radio & Space Physics, December , 1981)
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Abstract:
A technique for improving the coupling between a feed horn and reflector by using corrugated metallic flanges is presented.
Experimental data for flanges of varying parameters are given and theoretical explanation is supplemented
Nirmala, Paul; Dr.Krishna Pillai, M G(Cochin University Of Science And Technology, December 2, 1981)
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Abstract:
The thesis is a report of the attempts made to
prepare semiconducting and dielectric thin films and to
study their electrical properties. It consists of (i)
studies on the preparation and electrical characteristics
of compound semiconductor thin films of silver sulphide
and ferric hydroxide, and (ii) investigations on the electrical
and dielectric properties of plasma polymerized
thin films of para-toluidine element
Description:
Department
of Physics,Cochin University Of Science And Technology